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1.
World J Pediatr ; 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32193832

RESUMO

BACKGROUND: Maple syrup urine disease (MSUD) is an autosomal recessive inherited disorder that affects the degradation of branched-chain amino acids and is associated with acute and chronic brain dysfunction. This study presents 11 new patients with MSUD and describes the clinical characteristics and gene mutations reported in Chinese individuals. METHODS: During 2011-2018, 11 pedaitric patients with MSUD from 11 Chinese families were analyzed based on clinical characteristics and mass spectrometry, with confirmation via gene sequencing. Novel mutations affecting protein function were predicted with Mutation-Taster, PolyPhen-2, CADD and SIFT software. 3D models of the mutated proteins were generated by using the SWISS-MODEL online server, and the models were visualized in PyMOL. The characteristics and gene mutations in patients with MSUD were analyzed retrospectively. RESULTS: Seventeen mutations in the BCKDHA, BCKDHB and DBT genes were found, 8 of which are novel: c.55C>/T, c.349C>T, c.565C>T, c.808G>A, c.859C>G, and c.1270dupC in BCKDHA; c.275-2A>G in BCKDHB; and c.1291C>T in DBT. Eight patients died. Two patients had severe mental retardation and were physically handicapped. One patient with the intermediate type had relatively good prognosis, with mild psychomotor retardation and adiposity. Four mothers underwent amniocentesis for prenatal diagnosis during their second pregnancy; two fetuses were wild type, and two were carriers of one heterozygous mutation. CONCLUSIONS: Eight novel mutations were associated with MSUD in Chinese patients. Prenatal diagnosis was successfully performed by genetic analysis. Mutations in the BCKDHB gene were found in the majority of Chinese patients with MSUD.

2.
Adv Sci (Weinh) ; 6(22): 1901240, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31763143

RESUMO

Tissue engineering produces constructs with defined functions for the targeted treatment of damaged tissue. A complete spinal cord injury (SCI) model is generated in canines to test whether in vitro constructed neural network (NN) tissues can relay the excitatory signal across the lesion gap to the caudal spinal cord. Established protocols are used to construct neural stem cell (NSC)-derived NN tissue characterized by a predominantly neuronal population with robust trans-synaptic activities and myelination. The NN tissue is implanted into the gap immediately following complete transection SCI of canines at the T10 spinal cord segment. The data show significant motor recovery of paralyzed pelvic limbs, as evaluated by Olby scoring and cortical motor evoked potential (CMEP) detection. The NN tissue survives in the lesion area with neuronal phenotype maintenance, improves descending and ascending nerve fiber regeneration, and synaptic integration with host neural circuits that allow it to serve as a neuronal relay to transmit excitatory electrical signal across the injured area to the caudal spinal cord. These results suggest that tissue-engineered NN grafts can relay the excitatory signal in the completely transected canine spinal cord, providing a promising strategy for SCI treatment in large animals, including humans.

3.
Biomaterials ; 181: 15-34, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30071379

RESUMO

We have reported previously that bone marrow mesenchymal stem cell (MSC)-derived neural network scaffold not only survived in the injury/graft site of spinal cord but also served as a "neuronal relay" that was capable of improving the limb motor function in a complete spinal cord injury (SCI) rat model. It remained to be explored whether such a strategy was effective for repairing the large spinal cord tissue loss as well as restoring motor function in larger animals. We have therefore extended in this study to construct a canine MSC-derived neural network tissue in vitro with the aim to evaluate its efficacy in treating adult beagle dog subjected to a complete transection of the spinal cord. The results showed that after co-culturing with neurotropin-3 overexpressing Schwann cells in a gelatin sponge scaffold for 14 days, TrkC overexpressing MSCs differentiated into neuron-like cells. In the latter, some cells appeared to make contacts with each other through synapse-like structures with trans-synaptic electrical activities. Remarkably, the SCI canines receiving the transplantation of the MSC-derived neural network tissue demonstrated a gradual restoration of paralyzed limb motor function, along with improved electrophysiological presentation when compared with the control group. Magnetic resonance imaging and diffusion tensor imaging showed that the canines receiving the MSC-derived neural network tissue exhibited robust nerve tract regeneration in the injury/graft site. Histological analysis showed that some of the MSC-derived neuron-like cells had survived in the injury/graft site up to 6.5 months. Implantation of MSC-derived neural network tissue significantly improved the microenvironment of the injury/graft site. It is noteworthy that a variable number of them had integrated with the regenerating corticospinal tract nerve fibers and 5-HT nerve fibers through formation of synapse-like contacts. The results suggest that the transplanted MSC-derived neural network tissue may serve as a structural and functional "neuronal relay" to restore the paralyzed limb motor function in the canine with complete SCI.


Assuntos
Extremidades/inervação , Células-Tronco Mesenquimais/citologia , Traumatismos da Medula Espinal/terapia , Animais , Células Cultivadas , Imagem de Tensor de Difusão , Cães , Extremidades/fisiologia , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais/fisiologia , Neurônios Motores/citologia , Neurônios Motores/fisiologia , Rede Nervosa , Regeneração Nervosa/fisiologia , Células de Schwann
4.
R Soc Open Sci ; 4(12): 170980, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29308238

RESUMO

The interfacial compatibility between compact TiO2 and perovskite layers is critical for the performance of planar heterojunction perovskite solar cells (PSCs). A compact TiO2 film employed as an electron-transport layer (ETL) was modified using 3-aminopropyl trimethoxy silane (APMS) hydrolysate. The power conversion efficiency (PCE) of PSCs composed of an APMS-hydrolysate-modified TiO2 layer increased from 13.45 to 15.79%, which was associated with a significant enhancement in the fill factor (FF) from 62.23 to 68.04%. The results indicate that APMS hydrolysate can enhance the wettability of γ-butyrolactone (GBL) on the TiO2 surface, form a perfect CH3NH3PbI3 film, and increase the recombination resistance at the interface. This work demonstrates a simple but efficient method to improve the TiO2/perovskite interface that can be greatly beneficial for developing high-performance PSCs.

5.
Zhong Yao Cai ; 39(5): 1129-33, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-30133198

RESUMO

Objective: To study the metabonomics for heat-clearing and detoxifying health function of Lonicera japonica in rats. Methods: Male Wistar rats were treated with decoction of Lonicera japonica through intragastric for 5 d. GC-MS was used to detect the changes in rats serum metabolites. Mass spectrometry analysis,PCA and other technologies were used to analyze the differences among their metabolites,and analyzed the endogenous product. Results: There was a decline trend in citric acid cycle intermediates of Lonicera japonica treated group. On the contrary,amino acids and fatty acid intermediate product showed significant elevation,which revealed that the pathway of tricarboxylic acid cycle has been inhibited,and consistented with heat-clearing and detoxifying effect of Lonicera japonica. Conclusion: The metabonomics method by detecting the low-molecular-weight compounds can evaluate the heat-clearing and detoxifying health function of Lonicera japonica.


Assuntos
Lonicera , Metabolômica , Animais , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Masculino , Ratos , Ratos Wistar
6.
Int J Nanomedicine ; 10: 4639-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26229467

RESUMO

A synergistic approach by the combination of magnetic nanoparticles with an alternating magnetic field for transdermal drug delivery was investigated. Methotrexate-loaded silk fibroin magnetic nanoparticles were prepared using suspension-enhanced dispersion by supercritical CO2. The physiochemical properties of the magnetic nanoparticles were characterized. In vitro studies on drug permeation across skin were performed under different magnetic fields in comparison with passive diffusion. The permeation flux enhancement factor was found to increase under a stationary magnetic field, while an alternating magnetic field enhanced drug permeation more effectively; the combination of stationary and alternating magnetic fields, which has a massage-like effect on the skin, achieved the best result. The mechanistic studies using attenuated total reflection Fourier-transform infrared spectroscopy demonstrate that an alternating magnetic field can change the ordered structure of the stratum corneum lipid bilayers from the gel to the lipid-crystalline state, which can increase the fluidity of the stratum corneum lipids, thus enhancing skin penetration. Compared with the other groups, the fluorescence signal with a bigger area detected in deeper regions of the skin also reveals that the simulated massage could enhance the drug permeation across the skin by increasing the follicular transport. The combination of magnetic nanoparticles with stationary/alternating magnetic fields has potential for effective massage-like transdermal drug delivery.


Assuntos
Administração Cutânea , Sistemas de Liberação de Medicamentos/métodos , Fibroínas , Nanopartículas de Magnetita , Massagem , Animais , Fibroínas/administração & dosagem , Fibroínas/química , Fibroínas/farmacocinética , Cobaias , Nanopartículas de Magnetita/administração & dosagem , Nanopartículas de Magnetita/química , Pele/química , Pele/metabolismo
7.
Mol Med Rep ; 6(4): 750-4, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22797136

RESUMO

In various animal models of central neuronal diseases, both c-jun and nNOS genes are expressed inside injured neurons; however, the mechanism of these two genes in neuronal diseases remains uncertain. Our previous studies have shown that c-jun expression always occurs prior to expression of nNOS in motoneuron injuries. We aimed to determine whether there is a correlation between c-jun and nNOS, and whether the crosstalk between these two genes regulated the pathological progression of injury-induced neuronal degeneration. In the present study, we used the neuron-like differentiated PC12 cells, which express c-jun and nNOS, to examine whether c-jun is the upstream molecule modulating nNOS expression. The c-jun small interfering RNAs (c-jun siRNA) were transfected into PC12 cells and cells were treated for 72 h in vitro. Western blotting and immunofluorescence were used to check the protein levels and the expression of c-jun and nNOS in differentiated PC12 cells. The results from the immunofluorescence experiments showed that the c-jun and nNOS proteins were co-expressed in the differentiated PC12 cells. The results from the western blotting experiments revealed that the protein levels of c-jun were significantly decreased by c-jun siRNA. Moreover, the nNOS protein levels were also downregulated in differentiated PC12 cells following c-jun siRNA treatment. The present study found that siRNA used against c-jun not only knocked down c-jun, but also downregulated the nNOS protein expression in differentiated PC12 cells. These results indicate that there is a functional relationship between c-jun and nNOS in differentiated PC12 cells.


Assuntos
Óxido Nítrico Sintase Tipo I/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Animais , Diferenciação Celular , Regulação para Baixo , Expressão Gênica , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo I/genética , Células PC12 , Proteínas Proto-Oncogênicas c-jun/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-jun/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos
8.
J Neurochem ; 121(3): 362-72, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22339041

RESUMO

The signaling transduction processes involved in avulsion-induced motoneuron (MN) death have not been elucidated. Using the brachial plexus root avulsion rat model, we showed that avulsion-activated phosphorylation of phospholipase-Cγ (PLCγ) and protein kinase C (PKC) occurred in injured spinal MNs within 72 h of injury. Moreover, some MNs positive for PLCγ and PKC are also positive for avulsion-induced neuronal nitric oxide synthase (nNOS). Inhibition of PLCγ/PKC signal pathway, either with PLCγ inhibitor, 1-[6-((17ß-3-methoxyestra-1,3,5(10)-trien-17-yl) amino)hexyl]-1H-pyrrole-2,5-dione, or with PLCγ siRNA augmented avulsion-induced MN death. 1-[6-((17ß-3-methoxyestra-1,3,5(10)-trien-17-yl) amino)hexyl]-1H-pyrrole-2,5-dione also inhibited PKC phosphorylation and exacerbated avulsion-induced reductions in the nNOS protein level in injured spinal segments. Moreover, activation of PLCγ/PKC signal pathway with PKC activator, phorbol-12-myristate-13-acetate, decreased avulsion-induced MN death. The temporal profile of PLCγ/PKC signaling appears to be crucial for the survival of spinal MNs after root avulsion. Our data suggest that PLCγ mediates, while PKC and nNOS are associated with, the avulsion-induced MN death in brachial plexus root avulsion.


Assuntos
Neurônios Motores/efeitos dos fármacos , Neurônios Motores/patologia , Fosfolipase C gama/fisiologia , Proteína Quinase C/fisiologia , Radiculopatia/patologia , Transdução de Sinais/efeitos dos fármacos , Medula Espinal/patologia , Animais , Western Blotting , Contagem de Células , Morte Celular/efeitos dos fármacos , Estrenos/farmacologia , Imunofluorescência , Injeções Espinhais , Masculino , NADPH Desidrogenase/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Inibidores de Fosfodiesterase/farmacologia , Fosforilação , Pirrolidinonas/farmacologia , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Sprague-Dawley , Acetato de Tetradecanoilforbol/farmacologia
9.
Biomed Chromatogr ; 26(10): 1286-96, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22297903

RESUMO

Herbal formulations are complex natural mixtures. Researchers usually tend to focus more on analysis of nonvolatile components but pay less attention to volatile compounds. In this study, an analytical strategy combining two approaches was established for comprehensive analysis of herbal formulations. Guizhi Fuling capsule (GFC), a drug approved by the FDA to enter phase II clinical trial for treatment of primary dysmenorrhea, was taken as a case for analysis. Gas chromatography-mass spectrometry (GC-MS) with automated mass spectral deconvolution and identification system (AMDIS) led to rapid identification of 48 volatile components including four acetophenones, three fatty acid esters, 13 phenylpropanoids and 19 sesquiterpenes. Most of them were found from Guizhi. The volatile oils of Guizhi have been proved to exhibit many pharmacological activities. This is helpful in understanding the pharmacological mechanism of GFC. Furthermore, AMDIS turned out to be efficient and reliable for analysis of complex herbal formulations. Rapid-resolution liquid chromatography (RRLC) coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (ESI-Q-TOF MS/MS) allowed the identification of 70 nonvolatile components including six acetophenones, 12 galloyl glucoses, 31 monoterpene glycosides, three phenols and 12 triterpene acids. Fragmentation behaviors of assigned components, especially triterpene acids, which are hard to identify by low-resolution MS, were first investigated by TOF MS/MS. Characteristic ions and typical loss of assigned triterpene acids were summarized. Combinatorial use of GC-MS-AMDIS and RRLC-ESI-Q-TOF MS/MS could be of great help in global qualitative analysis of GFC, as well as other herbal products.


Assuntos
Medicamentos de Ervas Chinesas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas em Tandem/métodos , Compostos Orgânicos/análise , Compostos Orgânicos/química , Compostos Orgânicos/isolamento & purificação , Software
10.
Exp Neurol ; 234(2): 389-97, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22265659

RESUMO

Previous studies have shown that Interleukin-1 beta (IL-1ß) is implicated in the modulation of pain sensitivity. In the present study, we found that a single peri-sciatic administration of rat recombinant IL-1ß (rrIL-1ß) at doses of 20 and 200 pg (100, 1000 ng/l, in 200 µl volume) induced mechanical allodynia in bilateral hindpaws in rats, lasting for about 50 days. No axonal or Schwann cell damage at the drug administration site was found following 1000 ng/l rrIL-1ß administration. The results of immunofluorescence showed that microglial cells in bilateral spinal dorsal horn were activated after peri-sciatic administration of rrIL-1ß (1000 ng/l). The immunoreactivity (IR) of Iba1 (a marker for microglia) and phosphorylated src-family kinases (p-SFKs) increased significantly in the ipsilateral and contralateral lumbar spinal dorsal horn on day 1 and day 3 after rrIL-1ß administration, respectively. Double immunofluorescence staining revealed that the increased p-SFKs-IR was almost restricted within the microglia. Intrathecal delivery of minocycline (100 µg in 10 µl volume), a selective inhibitor of microglia, started 30 min before rrIL-1ß administration and once daily thereafter for 7 days, blocked mechanical allodynia induced by rrIL-1ß completely and inhibited the upregulation of p-SFKs. Intrathecal delivery of SFKs inhibitor PP2 (12 µg in 10 µl volume) also blocked mechanical allodynia induced by rrIL-1ß completely. These data suggest that activation of SFKs in spinal microglia mediates mechanical allodynia induced by peri-sciatic administration of rrIL-1ß.


Assuntos
Hiperalgesia/tratamento farmacológico , Interleucina-1beta/uso terapêutico , Microglia/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Quinases da Família src/metabolismo , Animais , Hiperalgesia/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/farmacologia , Masculino , Microglia/metabolismo , Medição da Dor/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , Fosforilação , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Medula Espinal/metabolismo
11.
Yao Xue Xue Bao ; 47(11): 1555-60, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23387092

RESUMO

Dried herb of Delphinium brunonianum Royle (Ranunculaceae) has long been used under the herbal name "Xiaguobei" (Delphinii Brunoniani Herba) in traditional Tibetan medicine and prescribed for the treatment of influenza, itchy skin rash and snake bites. In order to find a useful and convenient method for the identification of microscopic features, the technique of fluorescence microscopy was applied to authenticate "Xiaguobei" of Tibet. The transverse sections of stem and leaf, as well as the powder of "Xiaguobei" were observed to seek for typical microscopic features by normal light and fluorescence microscopy. A style-like, single-cell glandular hair containing yellow secretions on the leaf, young stem and sepal of "Xiaguobei" was found. Under the fluorescence microscope, the xylem and pericycle fiber group emitted significant fluorescence. This work indicated that fluorescence microscopy could be an useful additional method for the authentication work. Without the traditional dyeing methods, the main microscopic features could be easily found by fluorescence microscopy. The results provided reliable references for the authentication of "Xiaguobei".


Assuntos
Delphinium/anatomia & histologia , Plantas Medicinais/anatomia & histologia , Identificação Biométrica , Microscopia de Fluorescência , Folhas de Planta/anatomia & histologia , Caules de Planta/anatomia & histologia , Pós , Tibet
12.
Clin Exp Hypertens ; 33(5): 304-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21721987

RESUMO

The ambulatory arterial stiffness index (AASI) predicted stroke in hypertensive patients and in the general populations. However, no similar data was available in Chinese. In the present study, we sought confirmation that Chinese hypertensive patients with a history of stroke would have an elevated AASI. We retrospectively analyzed the data of 156 hypertensive outpatients (60.9 % men; mean age, 61.5 years) and 582 inpatients (63.6 % men; 58.6 years) of the Hypertension Department at Ruijin Hospital in Shanghai, China. The AASI was calculated as 1 - the regression slope of diastolic blood pressure (DBP) on systolic blood pressure (SBP) in individual 24-h ambulatory recordings. With adjustment applied for sex, age, body mass index (BMI), the 24-h mean arterial pressure, and other cardiovascular risk factors, AASI was higher in patients with a history of stroke than in patients without stroke in both outpatient (0.51 ± 0.02 vs. 0.47 ± 0.01; P = 0.050) and inpatient (0.46 ± 0.01 vs. 0.44 ± 0.01; P = 0.031) cohorts. The odds ratio (OR) for a history of stroke associated with a 1-SD increase in AASI was 1.63 (95% confidence interval (CI), 1.01-2.62; P = 0.046) in outpatients, 1.32 (1.01-1.74; P = 0.046) in inpatients, and 1.30 (1.05-1.62; P = 0.018) in two patient cohorts combined (n = 738) after multivariate adjustment including the night-to-day ratio of SBP. Our findings suggest that Chinese hypertensive patients with a history of stroke, compared to those without such history, have stiffer arteries, as exemplified by a higher AASI.


Assuntos
Hipertensão/complicações , Hipertensão/fisiopatologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/fisiopatologia , Rigidez Vascular/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Grupo com Ancestrais do Continente Asiático , China , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Estudos Retrospectivos , Fatores de Risco
13.
Microsc Res Tech ; 74(3): 269-80, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20623757

RESUMO

The light microscope has been successfully used in identification of Chinese herbal medicines (CHMs) for more than a century. However, positive identification is not always possible. Given the popularity of fluorescence microscopy in bioanalysis, researchers dedicated to finding new ways to identify CHMs more effectively are now turning to fluorescence microscopy for authentication purposes. Some studies on distinguishing confused species from the same genus and on exploring distributions of chemicals in tissues of CHMs by fluorescence microscopy have been reported; however, no systematic investigations on fluorescent characteristics of powdered CHMs have been reported. Here, 46 samples of 16 CHMs were investigated. Specifically, the mechanical tissues including stone cells and fibers, the conducting tissues including three types of vessels, and ergastic substances including crystals of calcium oxalate and secretions, in various powdered CHMs were investigated by both light microscope and fluorescence microscope. The results showed many microscopic features emit fluorescence that makes them easily observed, even against complex backgrounds. Under the fluorescence microscope, different microscopic features from the same powdered CHM or some same features from different powdered CHMs emitted the different fluorescence, making this information very helpful for the authentication of CHMs in powder form. Moreover, secretions with unique chemical profiles from different powdered CHMs showed different fluorescent characteristics. Hence, fluorescence microscopy could be a useful additional method for the authentication of powdered CHMs if the fluorescent characteristics of specific CHMs are known.


Assuntos
Medicamentos de Ervas Chinesas/química , Endotélio/efeitos dos fármacos , Microscopia de Fluorescência/métodos , Areca/efeitos adversos , Asparagus (Planta)/efeitos adversos , Oxalato de Cálcio/química , Oxalato de Cálcio/isolamento & purificação , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/análise , Retículo Endoplasmático/efeitos dos fármacos , Humanos , Jasminum/efeitos adversos , Ophiopogon/efeitos adversos , Prunus/efeitos adversos , Scrophularia/efeitos adversos
14.
Microsc Res Tech ; 74(1): 1-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21181703

RESUMO

Toxic and Potent Chinese Materia Medica (T/PCMM) is a special and very important category of Chinese medicines. They have long been used in traditional medical practice and are being used more and more widely throughout the world in recent years. As there may be many fatal toxic effects caused by misusing or confusion of T/PCMM, their quality and safety control arouse increasing attention internationally. Researches on the accurate identification to ensure the safe use of T/PCMM are acquired; however, there are few reports on authentication. We are carrying out a series of studies on 31 T/PCMM originating from plants, animals, minerals, and secreta. In our previous studies, we proved that modern microscopic authentication is a simple, fast, effective, low cost, and less toxic method for identifying animal, seed, and flower T/PCMM. In the present study, we focused on the authentication of four kinds of mineral arsenicals, including orpiment (mainly containing As2S3), realgar (mainly containing As4S4), arsenolite, and arsenic trioxide (mainly containing As2O3). We examined the macroscopic and microscopic characteristics of the above minerals and found that they all can be easily identified and authenticated by using light microscopy coupled with polarized microscopy. Moreover, the authentication results for arsenolite and arsenic trioxide are confirmed by ICP-MS analysis. We are sure that the morphological and microscopic characteristics indicated here are indispensable to establishing standards for these four mineral T/PCMMs.


Assuntos
Arsenicais/química , Medicamentos de Ervas Chinesas/química , Materia Medica/química , Microscopia/métodos , Cristalização , Contaminação de Medicamentos , Medicamentos de Ervas Chinesas/normas , Medicamentos de Ervas Chinesas/toxicidade , Espectrometria de Massas , Materia Medica/normas , Controle de Qualidade
15.
J Pharm Biomed Anal ; 50(1): 100-5, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19406598

RESUMO

A dynamic microdialysis sampling method with liquid chromatography-diode array detection and time-of-flight mass spectrometry (LC-DAD-TOF/MS) analysis was developed to investigate rat microsomal metabolisms of calycosin and formononetin, and their drug-drug interactions. Two hydroxylated metabolites from calycosin, and three hydroxylated or 4'-O-demethylated derivatives from formononetin were detected and identified after co-incubation with microsomes. Calibration curves offered linear ranges of two orders of magnitude with r(2)>0.999 for calycosin, formononetin and daidzein. The quantitative LC method provides a range of 0.028-0.034microg/mL for limits of detection, overall precision less than 5% and accuracy less than 3% by RSD. Besides, calycosin and formononetin were found to produce the depressive effect on the CYP450 enzyme reaction, and inhibit phase I enzyme reaction of each other when they are concurrent. Dynamic microdialysis sampling with LC-DAD-TOF/MS analysis developed in this work is a powerful tool for in vitro metabolism studies of drugs and metabolic interactions.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Isoflavonas/metabolismo , Espectrometria de Massas/métodos , Microssomos/metabolismo , Animais , Interações de Medicamentos , Microdiálise , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Chem Pharm Bull (Tokyo) ; 57(2): 144-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19182403

RESUMO

A highly specific and sensitive method using high performance liquid chromatography coupled with diode-array detection and ion-trap mass spectrometry (HPLC-DAD-MS(n)) was developed for study of the constituents of flavonoid extract of jujube seeds and the metabolites in rat plasma, urine, and feces samples after oral administration of flavonoid extract of jujube seeds. Two major flavonoids (spinosin and 6'''-feruloylspinosin) with content >60% in the flavonoid extract of jujube seeds were detected and confirmed by comparison with the reference standards. Furthermore, five metabolic components in plasma, seven in urine, and four in feces were detected and elucidated. The scientific and plausible biotransformation pathways of the main components in flavonoid extract of jujube seeds were also proposed, together with presentation of clues for potential bioactive mechanisms. This convenient HPLC-DAD-MS(n) method could be used to identify the chemical components of flavonoid extract of jujube seeds as well as their metabolites, and to reveal their possible metabolic mechanism of action in vivo.


Assuntos
Fezes/química , Flavonoides/química , Ziziphus/química , Animais , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Flavonoides/sangue , Flavonoides/urina , Masculino , Espectrometria de Massas , Modelos Moleculares , Dados de Sequência Molecular , Extratos Vegetais/farmacocinética , Ratos , Ratos Sprague-Dawley , Sementes/química , Soluções
17.
J Hazard Mater ; 162(2-3): 1159-64, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18684560

RESUMO

Three kinds of Ti-based multilayer metal-oxide electrode, including Ti/SnO(2)+Sb(2)O(3)/PbO(2), Ti/SnO(2)+Sb(2)O(3)/MnO(x) and Ti/SnO(2)+Sb(2)O(3)/RuO(2)+PbO(2) electrodes, were prepared by thermal decomposition, and SnO(2)+Sb(2)O(3) coatings were produced with a polymeric precursor method (PPM). The conversion of phenol was carried out with these electrodes as anodes under galvanostatic control. Samples during the electrolyses were characterized with UV-vis spectra and chromatography, and chemical oxygen demand (COD) and instantaneous current efficiency (ICE) for phenol degradation were also determined. The results show that phenol can be oxidized and degraded for all of the three anodes, and the oxidation reactions of phenol follow first-order kinetics, but there are considerable differences in the effectiveness and performance of electro-catalytic degradation. Phenol can be degraded relatively fast on the Ti/SnO(2)+Sb(2)O(3)/PbO(2) anode and the degradation rate of phenol is slower with the Ti/SnO(2)+Sb(2)O(3)/MnO(x) electrode, and the slowest with the Ti/SnO(2)+Sb(2)O(3)/RuO(2)+PbO(2) electrode, whose apparent rate constants are 2.49 x 10(-2), 1.42 x 10(-2) and 9.76 x 10(-3) min(-1), respectively. The rates of electro-catalytic degradation relate to oxygen evolution potential, and the higher the oxygen evolution potential, the better the performance of electro-catalytic degradation. The potential for oxygen evolution at the Ti/SnO(2)+Sb(2)O(3)/PbO(2) anode is highest, then Ti/SnO(2)+Sb(2)O(3)/MnO(x), following Ti/SnO(2)+Sb(2)O(3)/RuO(2)+PbO(2). The accelerated life tests at 60 degrees C and in 1.0 mol L(-1) aqueous H(2)SO(4) with an anodic current density of 4.0 Acm(-2) show that the service life is prolonged when the SnO(2)+Sb(2)O(3) interlayer coating are inserted between Ti substrate and active layers.


Assuntos
Eletroquímica , Eletrodos , Metais/química , Óxidos/química , Fenol/química , Catálise , Cinética , Espectrofotometria Ultravioleta
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(4): 743-6, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17608188

RESUMO

The determination of the conversion of styrene with UV spectroscopy was studied in microemulsion polymerization induced by ultrasound. The effects of SDS, pentrol and polystyrene on the styrene spectra were discussed. The experimental results show that the concentration of styrene in microemulsion polymerization system can be determined quantitatively at the wavelength of 247nm by UV spectroscopy, and the relationship between the styrene concentration and the absorbence is linear in the range of 9.7 x 10(-6) mol x L(-1)-6.95 x 10(-5) mol x L(-1), meanwhile the molar absorptivity is 1.384 x 10(4) L x mol(-1) x cm(-1). The SDS and pentrol presented in microemulsion polymerization system have no effects on the determination of the conversion of styrene. Polystyrene, a resultant in the process of microemulsion polymerization, could be removed by adding 95% alcohol to the microemulsion polymerization system and making polystyrene to be precipitated. Residual polystyrene does not affect the determination of the concentration of styrene. Comparing the results of UV spectroscopy with those of the chemical analysis and gravimetric analysis, the determination of the conversion of styrene by UV spectroscopy is feasible, and the process is simple and easy.

19.
J Chem Phys ; 125(21): 214506, 2006 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-17166032

RESUMO

Resonance Raman spectra were obtained for 2-nitrophenol in cyclohexane solution with excitation wavelengths in resonance with the charge-transfer (CT) proton transfer band absorption. These spectra indicate that the Franck-Condon region photodissociation dynamics have multidimensional character with motion along more than 15 normal modes: the nominal CCH bend+CC stretch nu(12) (1326 cm(-1)), the nominal CCC bend nu(23) (564 cm(-1)), the nominal CO stretch+NO stretch+CC stretch nu(14) (1250 cm(-1)), the nominal CCH bend+CC stretch+COH bend nu(15) (1190 cm(-1)); the nominal CCH bend+CC stretch nu(17) (1134 cm(-1)), the nominal CCC bend+CC stretch nu(22) (669 cm(-1)), the nominal CCN bend nu(27) (290 cm(-1)), the nominal NO(2) bend+CC stretch nu(21) (820 cm(-1)), the nominal CCO bend+CNO bend nu(25) (428 cm(-1)), the nominal CC stretch nu(7) (1590 cm(-1)), the nominal NO stretch nu(8) (1538 cm(-1)), the nominal CCC bend+NO(2) bend nu(20) (870 cm(-1)), the nominal CC stretch nu(6) (1617 cm(-1)), the nominal COH bend+CC stretch nu(11) (1382 cm(-1)), nominal CCH bend+CC stretch nu(9) (1472 cm(-1)). A preliminary resonance Raman intensity analysis was done and the results for 2-nitrophenol were compared to previously reported results for nitrobenzene, p-nitroaniline, and 2-hydroxyacetophenone. The authors briefly discuss the differences and similarities in the CT-band absorption excitation of 2-nitrophenol relative to those of nitrobenzene, p-nitroaniline, and 2-hydroxyacetophenone.

20.
Acta Crystallogr C ; 60(Pt 9): m454-6, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15345833

RESUMO

The title compound, [Zn(C7H4NO4)2(C12H8N2)(H2O)], has been synthesized. X-Ray analysis reveals that it is a neutral zinc(II) mononuclear carboxylate complex based on mixed N- and O-donor ligands. The Zn atom is five-coordinate in a distorted trigonal-bipyramidal coordination environment involving two O atoms of two monodentate 2-nitrobenzoate molecules, two N atoms of a 1,10-phenanthroline molecule and one O atom of a water molecule. The axial positions are occupied by a carboxylate O atom from the 2-nitrobenzoate ligand and an N atom from the 1,10-phenanthroline ligand [N-Zn-O = 167.66 (9) degrees].

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