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1.
Nurs Open ; 10(8): 4892-4906, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37120840

RESUMEN

AIM: To review the literature related to symptom management, clinical significance and related theoretical framework systems in adult patients with brain tumours. BACKGROUND: As understanding of symptoms or symptom clusters and underlying biologic mechanisms has grown, it is apparent that symptom science is moving forward. Although some progress has been made in the symptom science of solid tumours such as breast and lung neoplasms, insufficient attention has been paid to symptom management for patients suffering from brain tumours. Further research is needed to achieve effective symptom management for these patients. DESIGN: A literature review with a systematic search of symptom management in adult brain tumours. METHODS: Electronic data bases were searched to obtain relevant published literature on symptom management in adults with brain tumours. This was then analysed and a synthesis of relevant findings is presented. FINDINGS: Four significant general themes relating to symptom management of brain tumours in adults were identified: (1) The potential theoretical foundation related to symptom management was revealed. (2) Widely accepted validated scales or questionnaires for the assessment of single symptoms or symptom clusters were recommended. (3) Several symptom clusters and the underlying biologic mechanisms have been reported. (4) Specific symptom interventions for adults with brain tumours were collected and classified as evidence-based or insufficient evidence. CONCLUSION: There are still many challenges in the effective management of symptoms in adults with brain tumours. The guiding role of theoretical frameworks or models related to symptom management should be utilized in future research. Using the concept of symptom clustering for research into symptoms found in patients with brain tumours, exploring common biological mechanisms for specific symptom clusters and making full use of modern big data resources to build a strong evidence base for an effective intervention or management program may inform the management of symptoms among these patients leading to better results. NO PATIENT OR PUBLIC CONTRIBUTION: This is a literature review. IMPLICATIONS FOR SYMPTOM MANAGEMENT: The ultimate goal is obviously not only improving the survival rate of patients with brain tumours, but also enhancing their quality of life. Several important findings from our review include the theoretical foundations, validated assessment tools, the assessment of symptom clusters and the underlying biologic mechanism, and the identification of the evidence base for symptom interventions. These are of relevance for managers, researchers and practitioners and may function as a reference to help the effective symptom management for adults with brain tumours.


Asunto(s)
Productos Biológicos , Neoplasias Encefálicas , Neoplasias Pulmonares , Adulto , Humanos , Neoplasias Encefálicas/terapia , Calidad de Vida , Síndrome
2.
Zhongguo Zhong Yao Za Zhi ; 48(2): 382-389, 2023 Jan.
Artículo en Chino | MEDLINE | ID: mdl-36725228

RESUMEN

We prepared 15 batches of Kaixin Powder benchmark samples with the decoction pieces of different batches. Further, we established the specific chromatograms and index component content determination method of Kaixin Powder benchmark samples and analyzed the peaks and similarity of the chromatograms. With sibiricose A5, sibiricose A6, polygalaxanthone Ⅲ, 3,6'-disinapoyl sucrose, ginsenoside Rb_1, ß-asarone, α-asarone, and dehydropachymic acid as index components, the index component content determination method was established and 70%-130% of the mean content of each component was set as the range. The chromatograms of 15 batches of Kaixin Powder benchmark samples had a total of 22 characteristic peaks, among which 8 peaks were identified, which represented sibiricose A5, sibiricose A6, polygalaxanthone Ⅲ, 3,6'-disinapoyl sucrose, ginsenoside Rb_1, ß-asarone, α-asarone, and dehydropachymic acid, respectively. The chromatograms shared the similarity of 0.992-0.999. The 15 batches of benchmark samples had sibiricose A5 of 0.34-0.55 mg·g~(-1), sibiricose A6 of 0.43-0.57 mg·g~(-1), polygalaxanthone Ⅲ of 0.12-0.19 mg·g~(-1), 3,6'-disinapoyl sucrose of 1.08-1.78 mg·g~(-1), ginsenoside Rb_1 of 0.33-0.62 mg·g~(-1), ß-asarone of 2.34-3.72 mg·g~(-1), α-asarone of 0.11-0.22 mg·g~(-1), and dehydropachymic acid of 0.053-0.079 mg·g~(-1). This study established the specific chromatograms and index component content determination method of Kaixin Powder benchmark samples, and the method was simple, feasible, reproducible, and stable. This study provides a scientific basis for further research on the key chemical properties of the benchmark samples and preparations of Kaixin Powder.


Asunto(s)
Medicamentos Herbarios Chinos , Ginsenósidos , Polvos , Benchmarking , Medicamentos Herbarios Chinos/química , Sacarosa , Cromatografía Líquida de Alta Presión/métodos
3.
J Pharm Biomed Anal ; 216: 114802, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35500383

RESUMEN

Celosia argentea seed (CAS) has been used as a traditional Chinese medicine for the treatment of liver damage and eye diseases. CAS is easily falsely harvested and misused, five species from Amaranthaceae family have frequently found to be involved in the adulteration and misapplication, namely Celosia cristata seed (CCS), Amaranthus tricolor seed (ATS), Amaranthus retroflexus seed (ARS), Amaranthus cruentus seed (ACS), and Amaranthus spinosus seed (ASS). For the purpose of identification, multiple morphological means including stereomicroscopy, scanning electron microscopy, normal light and polarized light microscopy were comprehensively employed. As a result, micromorphological and microscopic characteristics were extracted and a diagnostic key to CAS and its five adulterants was proposed for the first time. With respect to the genetically closely related species, viz. CAS and CCS, chemical means were developed to achieve the goal of precise identification. Firstly, triterpenoid saponins in CAS and CCS were fully characterized by an HPLC-QTOF-MS/MS method, a total of 20 triterpenoid saponins including 9 novel members were identified. Secondly, the HPLC-ELSD specific chromatogram was established, in which 12 common peaks were assigned. Finally, after a careful comparison, the peak area ratio of two triterpenoid saponins was discovered as interspecies discriminant marker. In conclusion, CAS and its five adulterants can be precisely identified by multiple morphological and chemical means.


Asunto(s)
Amaranthus , Celosia , Saponinas , Triterpenos , Celosia/química , Saponinas/análisis , Semillas/química , Espectrometría de Masas en Tándem , Triterpenos/análisis
4.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(2): 299-304, 2022 Apr.
Artículo en Chino | MEDLINE | ID: mdl-35538766

RESUMEN

The incidence of obstructive sleep apnea (OSA) is higher in pregnancy than in non-pregnancy,and obesity is a major risk factor.OSA in pregnancy can lead to multiple organ dysfunction and is associated with hypertensive disorders in pregnancy,gestational diabetes mellitus,premature birth,and fetal growth restriction. Therefore,early screening and diagnosis are essential for the prevention and treatment of OSA in pregnancy.


Asunto(s)
Diabetes Gestacional , Complicaciones del Embarazo , Nacimiento Prematuro , Apnea Obstructiva del Sueño , Femenino , Humanos , Obesidad , Embarazo , Complicaciones del Embarazo/epidemiología , Factores de Riesgo , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/terapia
5.
Technol Cancer Res Treat ; 21: 15330338221074498, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35099325

RESUMEN

Object: By retrospectively analyzing the energy spectrum of squamous cell carcinoma, adenocarcinoma, small cell lung cancer (SCLC), and pulmonary metastases that underwent dual-layer detector spectral computed tomography (DLCT) 3-phase scan of the chest, we explored the value of a multiparameter energy spectrum in the assessment of pathological types of lung tumors. Methods: Cases of squamous cell carcinoma (n = 20), adenocarcinoma (n = 24), SCLC (n = 26), and metastases (n = 14) were collected. Then the largest cross-sectional area (LCA) of the lesion, computed tomography (CT) values in the plain scan phase, arterial and venous phases (HU, HUa, and HUv), iodine concentration, and effective atomic number in the arterial and venous phases (ICa, ICv, Zeff[a], and Zeff[v]) were measured and compared among the nonsmall cell lung cancer (NSCLC), SCLC and metastases, and other 3 groups of SCLC, squamous cell carcinoma, and adenocarcinoma. Results: Only the LCA is statistically different among SCLC, NSCLC, and metastases (P < .05). And the treated subgroup analysis did not show significant differences among the groups. However, the untreated subgroup analysis showed that there was a significant difference between NSCLC and metastases in LCA, SCLC and metastases in ICa, NSCLC and SCLC in HUv, NSCLC and SCLC in Zeff(v) (P < .05). Conclusion: The energy spectrum parameters of DLCT have a certain clinical value in distinguishing NSCLC from SCLC in the Zeff(v) and distinguishing SCLC from metastases in the ICa.


Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Tomografía Computarizada por Rayos X/métodos , Anciano , Toma de Decisiones Clínicas , Diagnóstico Diferencial , Manejo de la Enfermedad , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/normas
6.
J Enzyme Inhib Med Chem ; 36(1): 2104-2117, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34579614

RESUMEN

Tyrosinase (TYR) inhibitors are in great demand in the food, cosmetic and medical industrials due to their important roles. Therefore, the discovery of high-quality TYR inhibitors is always pursued. Natural products as one of the most important sources of bioactive compounds discovery have been increasingly used for TYR inhibitors screening. However, due to their complex compositions, it is still a great challenge to rapid screening and identification of biologically active components from them. In recent years, with the help of separation technologies and the affinity and intrinsic activity of target enzymes, two advanced approaches including affinity screening and inhibition profiling showed great promises for a successful screening of bioactive compounds from natural sources. This review summarises the recent progress of separation-based methods for TYR inhibitors screening, with an emphasis on the principle, application, advantage, and drawback of each method along with perspectives in the future development of these screening techniques and screened hit compounds.


Asunto(s)
Productos Biológicos/farmacología , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Monofenol Monooxigenasa/antagonistas & inhibidores , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Humanos , Estructura Molecular , Monofenol Monooxigenasa/metabolismo , Ultrafiltración
7.
Huan Jing Ke Xue ; 42(9): 4140-4150, 2021 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-34414712

RESUMEN

This study analyzed the seasonal variation, sources, and source-specific health risks of PM2.5-bound metals in Xinxiang city, Henan province. A total of 112 daily PM2.5 samples were collected over four consecutive seasons during 2019-2020. In total, 19 elements were identified using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The annual concentrations of PM2.5 and 11 heavy metals were calculated to be (66.25±35.73) µg·m-3 and (1.32±0.84) µg·m-3, respectively. Strong seasonal variations were observed in PM2.5 concentrations and the concentrations of associated metal elements, with the lowest concentrations all occurring in summer. The highest concentrations of dust-related elements (e.g., Al, Ca, Fe, Mg,and Ti) were recorded in spring, differing significantly from other elements, which all exhibited the highest mass concentrations in winter. The results apportioned from positive matrix factorization (PMF) and potential source contribution function (PSCF) models showed that the major sources of PM2.5-bound elements were Ni-and Co-related emissions (5.8%), motor vehicles (13.7%), Cd-related emissions(5.1%), combustion emissions (18.2%), and dust (57.3%). Health risk models showed that there were no obvious non-carcinogenic risks associated with these metals, because their hazard quotient (HQ) values were all below 1. Lifetime carcinogenic risks of the five apportioned sources were all higher than the acceptable level (1×10-6). Of these five sources, combustion emissions were the largest contributors to cancer risk (8.74×10-6, 36.9%) and non-cancer risk (0.60, 25.6%). This study suggests that control strategies to mitigate exposure risk in Xinxiang should emphasize reducing the sources of combustion emissions.


Asunto(s)
Metales Pesados , Material Particulado , Clima , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Material Particulado/efectos adversos , Material Particulado/análisis , Estaciones del Año
9.
Microsc Res Tech ; 83(12): 1530-1543, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32734676

RESUMEN

Prevention against the adulteration of traditional Chinese medicine in an accurate way has been long exploring. Vitex trifolia fruit (VTF), as a widely used analgesic in East Asia, has frequently been found to be adulterated with five adulterants, namely Vitex cannabifolia fruit (VCF) (Fam. Verbenaceae), Vitex negundo fruit (VNF) (Fam. Verbenaceae), Piper cubeba fruit (PCF) (Fam. Lauraceae), Euphorbia lathyris seed (ELS) (Fam. Euphorbiaceae), and Vaccinium bracteatum fruit (VBF) (Fam. Ericaceae). In this study, the methods of micromorphological identification, microscopic identification, and chemical analysis were combined to distinguish VTF from its five adulterants comprehensively. As a result, the micromorphological features in terms of fruit or seed epidermis were photographed by stereomicroscopy firstly. Secondly, the microscopic characteristics of various herb powders were captured under light microscopy. Thirdly, 33 nonvolatile components and 124 volatile components in VTF were identified by ultra-performance liquid chromatography coupled with Orbitrap mass spectrometry (UPLC-Orbitrap-MS) and comprehensive two-dimensional gas chromatography hyphenated with mass spectrometry (GC × GC-MS), respectively. Furthermore, betulinic acid, persicogenin, and the volatile 4-(2,2,6-trimethyl-bicyclo[4.1.0]hept-1-yl)-butan-2-one were screened out to be the specific markers of VTF distinctive from the adulterants. Collectively, VTF and its five adulterants were distinguished successfully by the comparison of micromorphological, microscopic characteristics, and chemical profiles.


Asunto(s)
Vitex , Frutas , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Masas , Medicina Tradicional China
10.
Pharmacol Res ; 159: 104987, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32512044

RESUMEN

In the present study, the concentrations of lead (Pb), cadmium (Cd), arsenic (As), mercury (Hg), and copper (Cu) in 2245 batches of Chinese herbal medicines (CHMs) were measured using inductively coupled plasma-mass spectroscopy (ICP-MS). We developed a risk assessment strategy that assessed the heavy metal-associated health risk of CHMs based on our large dataset. Using a combination of the mean and 95th percentile (P95) values of the chronic daily intake (CDI), hazard quotient (HQ), hazard index (HI), and lifetime cancer risk (CR), the health risks of the average exposure population and the high exposure population were estimated, respectively. To obtain a precise and realistic risk assessment, the exposure frequency and exposure duration were determined using questionnaire data from 20,917 randomly selected volunteers. Additionally, given the specific ingestion characteristics of CHMs, the safety factor and the transfer rates of heavy metals were highlighted as well. The concentrations of Pb, Cd, As, Hg, and Cu in 2245 batches of CHMs were 1.566, 0.299, 0.391, 0.074, and 8.386 mg/kg, respectively. The mean HI values indicated that consumption of most CHMs would not pose an unacceptable health risk to the average exposure population, except for argy wormwood leaf (1.326), morinda root (2.095), plantain herb (1.540), chrysanthemum flower (1.146), and Indian madder root (2.826). In addition, CR assessment for Pb and As revealed that, for the average exposure population, the risk of developing cancers was lower than the acceptable levels (1 × 10-4) in the clinic. However, the P95 of the HI and CR values indicated that more attention should be paid to the systemic effects of CHMs in terms of both non-carcinogenic and carcinogenic health risks for the high exposure population. Furthermore, in order to serve population health better, national and international guidelines have now been established. The risk assessment strategy developed in this study is the first of its kind, and contributed to the risk assessment, guidelines, and safety standards for heavy metals in CHMs.


Asunto(s)
Contaminación de Medicamentos , Medicamentos Herbarios Chinos/análisis , Metales Pesados/análisis , Adolescente , Adulto , Seguridad de Productos para el Consumidor , Medicamentos Herbarios Chinos/efectos adversos , Femenino , Humanos , Masculino , Espectrometría de Masas , Metales Pesados/efectos adversos , Persona de Mediana Edad , Seguridad del Paciente , Control de Calidad , Medición de Riesgo , Factores de Riesgo , Encuestas y Cuestionarios , Adulto Joven
11.
Orthop Surg ; 12(3): 708-716, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32436304

RESUMEN

Osteoarthritis (OA) is a common clinical degenerative disease characterized by the destruction of articular cartilage, which has an increasing impact on people's lives and social economy. The pathogenesis of OA is complex and unclear, and there is no effective way to block its progress. The study of the pathogenesis of OA is the prerequisite for the early diagnosis and effective treatment of OA. To define the pathogenesis of OA, this review considers the pathological mechanism of OA that involves microRNA, lncRNA, and exosomes. More and more evidence shows that microRNA, lncRNA, and exosomes are closely related to OA. MicroRNA inhibits the target gene by binding to the 3'- untranslated region of the targets. LncRNA usually competes with microRNA to regulate the expression level of downstream genes, while exosomes, as a carrier of intercellular information transfer, transmit the biological information of mother cells to target cells, and the effect of exosomes secreted by different cells on OA are different. In this review, we emphasized that different microRNA, lncRNA, and exosomes have different regulatory effects on chondrocyte proliferation and apoptosis, extracellular matrix degradation and inflammation. Besides, we classified and analyzed these molecules according to their effects on the progress of OA. Based on the analysis of the reported literature, this review reveals some pathogenesis of OA, and emphasizes that microRNA, lncRNA, and exosomes have great potential to assist early diagnosis and effective treatment of OA.


Asunto(s)
Exosomas/metabolismo , MicroARNs/metabolismo , Osteoartritis/metabolismo , Osteoartritis/patología , ARN Largo no Codificante/metabolismo , Progresión de la Enfermedad , Humanos
12.
Integr Cancer Ther ; 16(4): 526-539, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-27698265

RESUMEN

The BCR-ABL kinase inhibitor, imatinib mesylate, is the front-line treatment for chronic myeloid leukemia, but the emergence of imatinib resistance has led to the search for alternative drug treatments. There is a pressing need, therefore, to develop and test novel drugs. Natural products including plants, microorganisms, and halobios provide rich resources for discovery of anticancer drugs. In this article, we demonstrate that emodin inhibited the growth of K562 cells harboring BCR-ABL in vitro and in vivo, and induced abundant apoptosis, which was correlated with the inhibition of PETN/PI3K/Akt level and deletion of BCR-ABL. These findings suggest that emodin is a promising agent to kill K562 cells harboring BCR-ABL.


Asunto(s)
Antineoplásicos/farmacología , Emodina/farmacología , Proteínas de Fusión bcr-abl/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Fosfohidrolasa PTEN/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Apoptosis/efectos de los fármacos , Productos Biológicos/farmacología , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Mesilato de Imatinib/farmacología , Células K562 , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Transducción de Señal/efectos de los fármacos
13.
Huan Jing Ke Xue ; 37(4): 1219-29, 2016 Apr 15.
Artículo en Chino | MEDLINE | ID: mdl-27548940

RESUMEN

To explore the diurnal and seasonal characteristics of PM25, hourly PM25 concentration data ol It tixed monitoring sites in Chongqing urban area were collected continuously from June 2014 to May 2015. The result showed that: (1) the seasonal concentration of PM2.5 in different seasons decreased in the order of winter, autumn, spring and summer (P < 0.05), which were 100.2 microg x m(-3), 66.1 microg x m(-3), 45.9 microg x m(-3) and 33.4 microg x m(-3), respectively. (2) Monthly average concentrations of PM2.5 showed a single-peak curve, and the peaks of which occurred in January (P < 0.05, 120.8 microg x m(-3)). (3) For the whole year, daily variation of PM2.5 showed a jaggies curve. (4) Diurnal average concentrations of PM2.5 showed an obviously bimodal curve in winter, autumn and spring, hut it was less obvious in summer. (5) Daily PM25 concentration was significantly positively correlated with SO2, NO2 and CO (P < 0.01), indicating that the concentrations of SO2, NO2 and CO had a significant impact on the concentration of


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Monóxido de Carbono/análisis , China , Ciudades , Óxido Nitroso/análisis , Estaciones del Año , Análisis Espacio-Temporal , Dióxido de Azufre/análisis
14.
Zhongguo Zhong Yao Za Zhi ; 41(16): 3055-3059, 2016 Aug.
Artículo en Chino | MEDLINE | ID: mdl-28920348

RESUMEN

This study aims to establish quality standards of Aleuritopteris Herba (AH), which could supply scientific evidence for the quality control of AH. The morphological and microscopic identification characters were reformulated. The tests of water content, total ash, acid-insoluble ash and ethanol-soluble extractives of AH were carried out according to the methods recorded in appendix of Chinese Pharmacopeia (2010 edition, volume 1). The TLC method was established by using aleuritopesis A [2,19-diol(2ß,4α)-16-enekaureniod] and reference herb as references. With preparation of aleuritopesis A[2,19-diol(2ß,4α)-16-enekaureniod] reference substance, the content of aleuritopesis A in AH was determined by HPLC. As a result, the macroscopic identification, microscopic features and TLC methods were specific and simple. The water content, total ash, acid-insoluble ash and ethanol-soluble extractive and the content of aleuritopesis A of all samples varied in the ranges of 8.8%-10.9%, 7.6%-11.4%, 2.5%-4.2%, 9.3%-10.2% and 0.56%-0.71%, respectively. The improved quality standard can be used to evaluate and guarantee the quality of AH comprehensively.


Asunto(s)
Medicamentos Herbarios Chinos/normas , Pteridaceae/química , Cromatografía Líquida de Alta Presión , Control de Calidad , Investigación
15.
Yao Xue Xue Bao ; 46(5): 581-5, 2011 May.
Artículo en Chino | MEDLINE | ID: mdl-21800548

RESUMEN

The paper is to establish a method for simultaneous determination of 5 kinds of alkaloids in ephedra and poppy which are in Kechuanning tablets. Solid-phase extraction (SPE) was adopted in pretreatment, and a UPLC method with 2 different wavelengths had been developed: 210 nm for the detection of morphine, codeine phosphate, ephedrine hydrochloride and pseudoephedrine hydrochloride, and 251 nm for papaverine hydrochloride. The column used was Acquity UPLC BEH C18 (100 mm x 2.1 mm ID, 1.7 microm) with linear gradient elution using acetonitrile and 0.1% phosphoric acid. The flow rate was 0.4 mL.min-1, and the column temperature was 30 degrees C. The linear response range was 0.375 0 - 12.50 microg.mL-1 for morphine, 0.064 32 - 2.144 microg.mL-1 for codeine phosphate, 0.030 06 - 1.002 microg.mL-1 for papaverine hydrochloride, 1.126 - 37.52 microg.mL-1 for ephedrine hydrochloride, 0.287 8 - 9.592 microg.mL-1 for pseudoephedrine hydrochloride (r = 0.999 7). The average recoveries of these compounds were 99.26%, 100.6%, 95.29%, 100.1% and 97.48%, respectively. This is a more reasonable and credible method of quality control for Kechuanning tablets.


Asunto(s)
Alcaloides/análisis , Medicamentos Herbarios Chinos/química , Ephedra/química , Papaver/química , Cromatografía Líquida de Alta Presión , Codeína/análisis , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Efedrina/análisis , Morfina/análisis , Papaverina/análisis , Plantas Medicinales/química , Seudoefedrina/análisis , Control de Calidad , Extracción en Fase Sólida , Comprimidos
16.
Int J Biochem Cell Biol ; 34(10): 1241-7, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12127574

RESUMEN

It is well known that Mg(2+) is an essential component in many biological processes. This research investigated the courses of both the reactivation and the refolding in the absence and presence of Mg(2+) ions. Calf intestinal alkaline phosphatase (CIP) was extensively denatured in 3 M guanidine hydrochloride (GdnHCl) solution for 2 h. Under suitable renaturation conditions, about 60-70% of the activity was recovered in the absence and presence of different magnesium ion concentrations. The refolding processes followed two-phase courses, whereas the reactivation processes were monophasic after dilution in proper solutions with or without Mg(2+). The magnesium ions affected both the reactivation and the refolding courses of unfolded CIP. A comparison of rate constants for the refolding of unfolded CIP with those for recovery of enzyme activity at different Mg(2+) concentrations showed that they were not synchronized. The activity recovery was speeded up due to the presence of Mg(2+) ions; while the refolding course of unfolded CIP was somewhat inhibited by the excess Mg(2+).


Asunto(s)
Fosfatasa Alcalina/metabolismo , Antígenos de Neoplasias/metabolismo , Magnesio/metabolismo , Pliegue de Proteína , Fosfatasa Alcalina/química , Animales , Antígenos de Neoplasias/química , Bovinos , Activación Enzimática , Reactivadores Enzimáticos/metabolismo , Proteínas Ligadas a GPI , Guanidina/metabolismo , Técnicas In Vitro , Magnesio/química , Desnaturalización Proteica , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
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