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1.
Exploration (Beijing) ; 2(4): 20220059, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37325602

RESUMO

Lithium niobate (LN) is a type of multifunctional dielectric and ferroelectric crystal that is widely used in acoustic, optical, and optoelectronic devices. The performance of pure and doped LN strongly depends on various factors, including its composition, microstructure, defects, domain, and homogeneity. The structure and composition homogeneity can affect both the chemical and physical properties of LN crystals, including their density, Curie temperature, refractive index, and piezoelectric and mechanical properties. In terms of practical demands, both the composition and microstructure characterizations these crystals must range from the nanometer scale up to the millimeter and wafer scales. Therefore, LN crystals require different characterization technologies when verifying their quality for various device applications. Optical, electrical, and acoustic technologies have been developed, including x-ray diffraction, Raman spectroscopy, electron microscopy, and interferometry. To obtain detailed structural information, advanced sub-nanometer technologies are required. For general industrial demands, fast and non-destructive technologies are preferable. This review outlines the advanced methods used to characterize both the composition and homogeneity of LN melts and crystals from the micro- to wafer scale.

2.
Breed Sci ; 67(3): 221-232, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28744175

RESUMO

The maturity date of soybean (Glycine max (L.) Merr.) is sensitive to photoperiod, which varies with latitude and growing seasons. The maturity group (MG) system, composed of 13 MGs, is a major approach in characterizing varieties' ecological properties and adaptable areas. A total of 512 world soybean varieties, including 48 MG checks, were tested at a major site (Nanjing, 32.04°N) with portions tested in supplementary sites (Heihe, 50.22°N; Mudanjiang, 44.60°N; Jining, 35.38°N and Nanning, 22.84°N) in China to explore the world-wide MG distribution. The maturity date of the world soybean varied greatly (75-201 d) in Nanjing. Along with soybeans disseminated to new areas, the MGs further expanded during the last 70 years from MG I-VII to the early MG 0-000 in the north continents and to the late MG VIII-X in the south continents with the growth period structure differentiated into two subgroups in each MG 0-VIII except V. The cluster analysis among MGs and subgroups using genome-wide markers validated the MG sequential emergence order and the subgroup differentiation in eight MGs. For future evaluation, in addition to one major site (Nanjing), one supplementary southern site (Nanning) and one supplementary northern site (Heihe) are sufficient.

3.
Wei Sheng Wu Xue Bao ; 48(5): 690-4, 2008 May.
Artigo em Chinês | MEDLINE | ID: mdl-18652305

RESUMO

OBJECTIVE: To study the effect of Bt9875 crystal protein treated with proteinase K on human cancer cells, HL-60. METHODS: We used the methods of Thiazolyl Blue Tetrazolium Bromide, fluorescence microscopy examination, agarose gel electrophores and flow cytometry to detect the growth inhibition rate and apoptosis characters of the HL-60 cells that were treated with different concentration of Bt9875 crystal protein. RESULTS: Bt9875 crystal protein inhibited the growth of HL-60 cells evidently in a dose-dependent manner, with minimal effects on normal human peripheral blood mononuclear cells (PBMCs). The nuclei of HL-60 cells showed the characteristics of apoptosis. The analysis by flow cytometry indicated that the apoptosis rate of HL-60 cells was 52% after treatment with Bt9875 crystal protein (100 microg/mL). DNA analyzed by agarose gel electrophoresis showed "ladder" pattern. CONCLUSION: Bt9875 crystal protein could inhibit the growth of HL-60 and induced its apoptosis, which provided a foundation for use of Bt9875 crystal protein to cure the acute myeloid leukemia.


Assuntos
Apoptose/efeitos dos fármacos , Bacillus thuringiensis/química , Proteínas de Bactérias/farmacologia , Endotoxinas/farmacologia , Proteínas Hemolisinas/farmacologia , Bacillus thuringiensis/classificação , Bacillus thuringiensis/isolamento & purificação , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/isolamento & purificação , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Endotoxinas/isolamento & purificação , Citometria de Fluxo , Células HL-60 , Proteínas Hemolisinas/isolamento & purificação , Humanos , Microscopia de Fluorescência
4.
Planta Med ; 73(7): 669-74, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17538869

RESUMO

Red Asian ginseng ( Panax ginseng C. A. Meyer, Araliaceae) is used in many Oriental countries. In this study, the saponin constituents and anticancer activities of steamed American ginseng ( Panax quinquefolius L.) roots were evaluated. The contents of 12 ginsenosides in the roots were determined using high performance liquid chromatography (HPLC). After the steaming treatment (100 - 120 degrees C for 1 h and 120 degrees C for 0.5 - 4 h), the quantity of 7 ginsenosides decreased and that of 5 others increased. The content of ginsenoside Rg3, a previously recognized anticancer compound, increased significantly when the root was steamed at 120 degrees C for 0.5 - 3 h. The antiproliferative effects of unsteamed and steamed (120 degrees C for 1 h and 2 h) American ginseng root extracts were assayed by the modified trichrome stain (MTS) method using three cancer cell lines (SW-480, HT-29, NSCLC). Heat-processing increased the antiproliferative effect of American ginseng significantly, and the activity of the extract from roots steamed for 2 h was greater than that of roots steamed for 1 h. Chemical constituents and antiproliferative activities of white and red Asian ginseng have also been evaluated. Five representative ginsenosides, Rb1, Rd, Re, Rg2 and Rg3, were studied. Ginsenoside Rg3 had the most potent effect. The antiproliferative activities of red American ginseng are augmented when ginsenoside Rg3 is increased.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ginsenosídeos/farmacologia , Panax , Fitoterapia , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ginsenosídeos/administração & dosagem , Ginsenosídeos/química , Ginsenosídeos/uso terapêutico , Temperatura Alta , Humanos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Raízes de Plantas
5.
J Agric Food Chem ; 54(6): 2261-6, 2006 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-16536605

RESUMO

The root of American ginseng is a commonly used herbal medicine in the United States. However, the compositions of American ginseng leaves and berries are not clear to date. In this study, we improved a method for the analysis of 12 ginsenosides based on solid phase extraction and high-performance liquid chromatography-ultraviolet. Good resolution was obtained for all tested ginsenosides: Rb1, Rb2, Rb3, Rc, Rd, Re, Rg1, Rg2, 20(R)-Rg2, Rg3, Rh1, and Rh2. Ginsenosides Rh1, Rg2, and 20(R)-Rg2 were easily separated with this column. The modified gradient elution program resulted in satisfactory linearity and precision. Solid phase extraction made the analysis accurate and efficient. Other investigators recently observed that ginsenoside Rb3 is a potent neuroprotective compound; it can promote learning and memory. In this report, we found that the major ginsenoside in American ginseng leaves and berries was ginsenoside Rb3, while Rb3 only had limited amounts in the root of American ginseng and other species of the Panax genus. Ginsenoside Rb3 was quantified as 4.71% in American ginseng leaves and 5.35% in berries, suggesting that American ginseng leaves and berries are new sources of ginsenoside Rb3.


Assuntos
Cromatografia Líquida de Alta Pressão , Frutas/química , Panax/química , Folhas de Planta/química , Saponinas/análise , Ginsenosídeos/análise
6.
Phytochem Anal ; 16(4): 272-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16042154

RESUMO

In order to determine the active ingredients in root extracts of Panax quinquefolius (American ginseng), a gradient HPLC method involving UV photodiode array detection was applied to separate and quantify simultaneously the ginsenosides Rb1, Rb2, Rc, Rd, Re, Rf and Rg1. All ginseng saponins were baseline-resolved under the selected conditions, and the detection limits were 1.0 microg/mL or less. The method has been applied to analyse ginsenosides extracted from American ginseng cultivated in both Wisconsin and Illinois. Ginsenosides Re and Rb1 were the two main ginseng saponins in the root. The amounts of Re in 5- and 7-year Illinois-cultivated samples were greater than those found in ginseng cultivated for 3 or 4 years in Wisconsin, whereas the levels of Rb1 were greater in the younger Wisconsin samples.


Assuntos
Ginsenosídeos/isolamento & purificação , Panax/química , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Raízes de Plantas/química , Espectrofotometria Ultravioleta
7.
Biochim Biophys Acta ; 1740(3): 319-25, 2005 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-15949698

RESUMO

We evaluated the anti-diabetic effects of ginsenoside Re in adult male C57BL/6J ob/ob mice. Diabetic ob/ob mice with fasting blood glucose levels of approximately 230 mg/dl received daily intraperitoneal injections of 7, 20 and 60 mg/kg ginsenoside Re for 12 consecutive days. Dose-related effects of ginsenoside Re on fasting blood glucose levels were observed. After the 20 mg/kg treatment, fasting blood glucose levels were reduced to 188+/-9.2 and 180+/-10.8 mg/dl on Day 5 and Day 12, respectively (both P<0.01 compared to vehicle group, 229+/-9.5 and 235+/-13.4 mg/dl, respectively). The EC(70) of ginsenoside Re was calculated to be 10.3 mg/kg and was used for subsequent studies. Consistent with the reduction in blood glucose, there were significant decreases in both fed and fasting serum insulin levels in mice treated with ginsenoside Re. With 12 days of ginsenoside treatment, glucose tolerance of ob/ob mice increased significantly, and the area under the curve for glucose decreased by 17.8% (P<0.05 compared to vehicle treatment). The hypoglycemic effect of the ginsenoside persisted even at 3 days of treatment cessation (blood glucose levels: 198+/-13.1 with ginsenoside treatment vs. 253+/-20.3 mg/dl with vehicle, P<0.01). There were no significant changes in body weight or body temperature. Preliminary microarray analysis revealed differential expression of skeletal muscle genes associated with lipid metabolism and muscle function. The results suggest that ginsenoside Re may prove to be useful in treating type 2 diabetes.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/terapia , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Análise de Variância , Animais , Relação Dose-Resposta a Droga , Insulina/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fatores de Tempo
8.
Pharmacol Res ; 49(2): 113-7, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14643691

RESUMO

Previous studies showed that both American ginseng root and American ginseng berry extracts possess hypoglycemic properties. In this study, we investigated whether American ginseng leaves also have similar capabilities. We first analyzed the chemical constituents of American ginseng leaf and determined the content of six major ginsenosides, i.e., Rb(1), Rb(2), Rc, Rd, Re, and Rg(1), by high performance liquid chromatography (HPLC). Subsequently, we evaluated the hypoglycemic effect of American ginseng leaf extract (AGLE) in diabetic ob/ob adult mice. Animals received daily intraperitoneal injections of AGLE 50, 150 mg/kg or vehicle for 12 consecutive days. Fasting blood glucose levels, intraperitoneal glucose tolerance test (IPGTT), body weight and temperature were measured. On day 5, the 150 mg/kg AGLE group had significantly lower fasting blood glucose levels compared to vehicle-treated mice (223.0+/-13.9 mg/dl versus 258.0+/-14.0 mg/dl, P<0.05), while the blood glucose levels in 50 mg/kg group did not decrease significantly. On day 12, the glucose levels in both AGLE-treated groups were reduced significantly compared to vehicle group (180.0+/-10.0 mg/dl and 220.2+/-19.3 versus 268.0+/-10.0 mg/dl, P<0.01 and <0.05, respectively). IPGTT data showed that both AGLE 150 and 50 mg/kg groups significantly increased the glucose disposal on day 12 compared to the vehicle group. In addition, body weight decreased in ob/ob mice after AGLE treatment, and these body weight changes were accompanied by significant increases in body temperature (P<0.05). Our results suggest that AGLE possesses a significant anti-hyperglycemic and thermogenic activity and may prove to be beneficial in improving the management of type 2 diabetes.


Assuntos
Ginsenosídeos/farmacologia , Hipoglicemiantes/farmacologia , Panax , Animais , Glicemia/análise , Temperatura Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Jejum , Ginsenosídeos/análise , Teste de Tolerância a Glucose , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Obesos , Panax/química , Extratos Vegetais/farmacologia , Folhas de Planta/química
9.
Cancer Chemother Pharmacol ; 52(6): 453-8, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12942313

RESUMO

PURPOSE: Nausea/vomiting are significant side effects associated with the use of chemotherapy in cancer patients. Treatment of nausea/vomiting caused by cisplatin, a potent chemotherapeutic agent and one of the most emetogenic stimuli, requires a combination of different antiemetic drugs. In this study, we investigated the effects of Scutellaria baicalensis, an antioxidant herbal medicine, on cisplatin-induced nausea using a rat model. METHODS: Rats react to emetic/nausea-producing stimuli, such as cisplatin, with altered feeding habits, manifested by pica or increased consumption of kaolin (a type of clay). We measured pica in rats to quantify cisplatin-induced nausea, and to evaluate the antinausea effect of pretreatment with S. baicalensis extract (SbE) given intraperitoneally. RESULTS: Cisplatin at 3 mg/kg induced significant pica accompanied by reduced food intake, suggesting the presence of nausea. Hence, this cisplatin dose was selected for testing the antinausea activity of SbE. Cisplatin-induced pica decreased significantly when animals were pretreated with SbE at doses of 1 mg/kg and 3 mg/kg ( P<0.01). At a higher SbE dose (10 mg/kg), kaolin consumption increased, rather than further decreased, and was significantly different from that in the groups treated with low SbE doses. CONCLUSIONS: SbE pretreatment decreased cisplatin-induced kaolin intake in the rat model of simulated nausea, suggesting that SbE and its active constituent(s) may play a therapeutic role in chemotherapy-induced emesis. Absence of therapeutic effect at the highest tested SbE dose could have been a result of prooxidant activity often associated with excess antioxidant concentration.


Assuntos
Antieméticos/uso terapêutico , Antineoplásicos/toxicidade , Cisplatino/toxicidade , Medicamentos de Ervas Chinesas/uso terapêutico , Pica/tratamento farmacológico , Scutellaria baicalensis/química , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Injeções Intraperitoneais , Caulim , Masculino , Náusea/induzido quimicamente , Náusea/tratamento farmacológico , Pica/induzido quimicamente , Raízes de Plantas/química , Ratos , Ratos Wistar
10.
Artigo em Inglês | MEDLINE | ID: mdl-12401350

RESUMO

A high-performance liquid chromatographic (HPLC) method with electrochemical detection and solid-phase extraction (SPE) using cartridges of weak cation-exchange capacity as the primary retention mechanism is described for the separation and determination of methylnaltrexone (MNTX) in small clinical samples of plasma or urine. The procedure was performed using a Phenomenex Prodigy ODS-2, 5 microm, 150x3.2 mm analytical column and 50 mM potassium acetate buffer, with 11% methanol as organic modifier at pH* 4.5 at a flow-rate of 0.5 ml/min. The detection potential was 700 mV. The six-point standard calibration curves were linear over three consecutive days in the range from 2 to 100 ng/ml. The average goodness of fit (r) was 0.9993. The lower limit of detection (LOD) and limit of quantification (LOQ) were found to be 2.0 and 5.0 ng/ml, respectively. At the LOQ, the coefficient of variation for the entire method was 8.0% and the accuracy was 10.0% (n = 10). Recovery of the drug from plasma was in the region of 94%. The method was applied to a pharmacokinetics study of methylnaltrexone after subcutaneous administration and in numerous assays of analytes in blood plasma and urine. The pharmacokinetics parameters for a single dose of 0.1 or 0.3 mg/kg in plasma were C(max) = 110 (+/-55) and 287 (+/-101) ng/ml and t(max) = 16.7 (+/-10.8) and 20.0 (+/-9.5) min, respectively. The method is simple, yet sensitive for the detection and determination of methylnaltrexone in biological samples at the level of the physiological response.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Naltrexona/análogos & derivados , Naltrexona/farmacocinética , Antagonistas de Entorpecentes/farmacocinética , Calibragem , Humanos , Naltrexona/sangue , Naltrexona/urina , Antagonistas de Entorpecentes/sangue , Antagonistas de Entorpecentes/urina , Compostos de Amônio Quaternário , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Am J Chin Med ; 30(2-3): 187-94, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12230007

RESUMO

In this study, we evaluated antihyperglycemic effects of American ginseng berry extract in diabetic ob/ob mice. Animals received daily intraperitoneal (IP) injections of the extract 150 mg/kg for 12 days. On days 5 and 12, the extract-treated ob/ob mice had significantly lower fasting blood glucose levels compared to day 0 (both p < 0.05). Glucose tolerance improved significantly, which was shown by overall glucose excursion, calculated as area under the curve (AUC) during the two-hour IP glucose tolerance test. The AUC decreased by 31.8% on day 12 compared to day 0 (p < 0.01). In addition, after 12 days of the berry extract treatment, a significant reduction in body weight (p < 0.01 compared to day 0) and a significant increase in body temperature (p < 0.01 compared to day 0) was noticeable. Our results support in vivo antihyperglycemic and antiobese activity of American ginseng berry extract that may prove to be of clinical importance in the prevention and treatment of Type 2 diabetes.


Assuntos
Glicemia/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Panax , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Área Sob a Curva , Temperatura Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Frutas/química , Teste de Tolerância a Glucose , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/uso terapêutico , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Obesos , Obesidade , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacocinética , Extratos Vegetais/uso terapêutico
12.
Diabetes ; 51(6): 1851-8, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12031973

RESUMO

We evaluated antihyperglycemic and anti-obese effects of Panax ginseng berry extract and its major constituent, ginsenoside Re, in obese diabetic C57BL/6J ob/ ob mice and their lean littermates. Animals received daily intraperitoneal injections of Panax ginseng berry extract for 12 days. On day 12, 150 mg/kg extract-treated ob/ob mice became normoglycemic (137 +/- 6.7 mg/dl) and had significantly improved glucose tolerance. The overall glucose excursion during the 2-h intraperitoneal glucose tolerance test decreased by 46% (P < 0.01) compared with vehicle-treated ob/ob mice. The improvement in blood glucose levels in the extract-treated ob/ ob mice was associated with a significant reduction in serum insulin levels in fed and fasting mice. A hyperinsulinemic-euglycemic clamp study revealed a more than twofold increase in the rate of insulin-stimulated glucose disposal in treated ob/ ob mice (112 +/- 19.1 vs. 52 +/- 11.8 micromol x kg(-1) x min(-1) for the vehicle group, P < 0.01). In addition, the extract-treated ob/ob mice lost a significant amount of weight (from 51.7 +/- 1.9 g on day 0 to 45.7 +/- 1.2 on day 12, P < 0.01 vs. vehicle-treated ob/ob mice), associated with a significant reduction in food intake (P < 0.05) and a very significant increase in energy expenditure (P < 0.01) and body temperature (P < 0.01). Treatment with the extract also significantly reduced plasma cholesterol levels in ob/ob mice. Additional studies demonstrated that ginsenoside Re plays a significant role in antihyperglycemic action. This antidiabetic effect of ginsenoside Re was not associated with body weight changes, suggesting that other constituents in the extract have distinct pharmacological mechanisms on energy metabolism.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Ginsenosídeos , Hipoglicemiantes/uso terapêutico , Obesidade , Panax , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Glicemia/análise , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Jejum , Frutas/química , Técnica Clamp de Glucose , Teste de Tolerância a Glucose , Insulina/sangue , Cinética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Saponinas/uso terapêutico
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