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1.
Nature ; 565(7737): 82-85, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30455423

RESUMEN

Levallois approaches are one of the best known variants of prepared-core technologies, and are an important hallmark of stone technologies developed around 300,000 years ago in Africa and west Eurasia1,2. Existing archaeological evidence suggests that the stone technology of east Asian hominins lacked a Levallois component during the late Middle Pleistocene epoch and it is not until the Late Pleistocene (around 40,000-30,000 years ago) that this technology spread into east Asia in association with a dispersal of modern humans. Here we present evidence of Levallois technology from the lithic assemblage of the Guanyindong Cave site in southwest China, dated to approximately 170,000-80,000 years ago. To our knowledge, this is the earliest evidence of Levallois technology in east Asia. Our findings thus challenge the existing model of the origin and spread of Levallois technologies in east Asia and its links to a Late Pleistocene dispersal of modern humans.


Asunto(s)
Arqueología , Cuevas , Fósiles , Hominidae , Comportamiento del Uso de la Herramienta , África , Animales , China , Europa (Continente) , Asia Oriental , Historia Antigua , Humanos , Factores de Tiempo
2.
Environ Toxicol ; 33(9): 923-930, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29962088

RESUMEN

Eclipta prostrata, a traditional Chinese medication, has been used for the treatment of several diseases. However, the molecular mechanism underlying the effects of Eclipta prostrata extracts (EPE) on human oral cancer cell metastasis remains unclear. We thus examined the effects of EPE on metastasis promoting proteins in oral cancer. Our results revealed that the EPE attenuated SCC-9, HSC-3, and TW2.6 cell migration and invasiveness by reducing matrix metalloproteinase (MMP)-2 enzyme activities. In addition, Western blot analysis revealed that EPE significantly reduced the levels of phosphorylated extracellular signal-regulated kinase 1/2 (ERK 1/2) but not those of c-Jun N-terminal kinase (JNK) 1/2 and p38. In conclusion, we found that EPE could inhibit oral cancer metastasis through the inhibition of MMP-2 expression. Therefore, EPE may be used to prevent the metastasis of oral cancer, and has the potential to be applied to cancer treatment.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Medicamentos Herbarios Chinos/farmacología , Eclipta/química , Neoplasias de la Boca/patología , Adulto , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Persona de Mediana Edad , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Invasividad Neoplásica , Metástasis de la Neoplasia , Fosforilación
3.
Zhong Yao Cai ; 38(4): 821-6, 2015 Apr.
Artículo en Zh | MEDLINE | ID: mdl-26672352

RESUMEN

OBJECTIVE: To study the prescription and preparation technology of breviscapine self-microemulsion for oral administration, and to evaluate the quality, stability and in vitro dissolution. METHODS: The prescription and preparation technology were selected and optimized through the solubility experiment, compatibility test, and pseudo-ternary phase diagram method, using the self-emulsifying time, appearance, particle diameter and stability as indexes. The droplet morphous, drug content, stability and dissolution were evaluated. Results:The prescription composition of breviscapine self-microemulsion was caprylic/capric triglyceride(GTCC,40%), Cremophor RH-40(50%), and PEG-400 (10%), with the drug loading of 7. 0 mg/g. The breviscapine self-microemulsion exhibited uniform and transparent,with the particle size of 38. 57 nm,Zeta potential of - 8. 80 mV. The results of dissolution indicated that the accumulative dissolution in 0. 1 mol/L hydrochloric acid was able to reach 90. 30% after 90 min, being 5. 9 times to that of the raw material medicine. The stability result showed that the content of breviscapine self-microemulsion was affected by high temperature, indicating it should be stored at low temperature. CONCLUSION: The preparation of breviscapine self-microemulsion is simple, which can increase the solubility of breviscapine in water and the absorption of breviscapine in the stomach and intestine, and conform to the main indexes of oral drug delivery system. It offers the basis for further research of breviscapine.


Asunto(s)
Sistemas de Liberación de Medicamentos , Emulsiones , Flavonoides/química , Administración Oral , Medicamentos Herbarios Chinos , Tamaño de la Partícula , Solubilidad
4.
Yao Xue Xue Bao ; 47(2): 163-7, 2012 Feb.
Artículo en Zh | MEDLINE | ID: mdl-22512025

RESUMEN

Hot-melt extrusion (HME) is mainly used to enhance the dissolution rate and bioavailability of poorly water soluble drugs. It has many advantages, such as simple process, continuous operation, high efficiency, on-line monitoring and so on. HME provides an innovative approach, which has been concerned by pharmaceutical workers, for preparation of solid dispersion abroad. This article reviews recent advances on preparation of solid dispersion by HME in preparation processing, carrier materials and quality evaluation in order to further promote and apply HME in preparation of solid dispersion.


Asunto(s)
Calor , Preparaciones Farmacéuticas/química , Tecnología Farmacéutica/métodos , Disponibilidad Biológica , Química Farmacéutica , Formas de Dosificación , Portadores de Fármacos , Composición de Medicamentos , Presión , Solubilidad
5.
Front Cardiovasc Med ; 8: 704446, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34250051

RESUMEN

Background: The metabolic syndrome (MS) is significantly associated with the risk of incident heart failure (HF). However, there are still great controversies about the impact of MS on the prognosis in patients with established HF. This meta-analysis aimed to ascertain the effect of MS on the prognosis in patients with HF. Methods: We searched multiple electronic databases, including PubMed, Opengrey, EMBASE, and Cochran Library, for potential studies up to February 15, 2021. Observational studies that reported the impact of MS on the prognosis in patients with established HF were included for meta-analysis. Results: Ten studies comprising 18,590 patients with HF were included for meta-analysis. The median follow-up duration of the included studies was 2.4 years. Compared with HF patients without MS, the risk of all-cause mortality and cardiovascular mortality was not increased in HF with MS (HR = 1.04, 95% CI = 0.88-1.23 for all-cause mortality; HR = 1.66, 95% CI = 0.56-4.88 for cardiovascular mortality, respectively). However, there was a significant increase in composited cardiovascular events in the HF patients with MS compared with those without MS (HR = 1.73, 95% CI = 1.23-2.45). Conclusions: In patients with established HF, the presence of MS did not show an association on the risk of all-cause mortality or cardiovascular mortality, while it may increase the risk of composite cardiovascular events.

6.
Chin J Nat Med ; 12(2): 103-7, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24636059

RESUMEN

Research has demonstrated that many chemical constituents dominated by piperidine alkaloids and flavonoids, such as lobelanidine, lobeline, and lobelanine, have been obtained from Lobelia chinensis Lour. Experimental studies and clinical applications have also indicated that L. chinensis possesses a number of pharmacological activities (e.g., diuretic, choleretic, breathing excitement, anti-venom, anti-bacterial, and anticancer). This paper focuses on the properties, chemical constituents, and anticancer activity of L. chinensis to clarify the connection among them, and identify the active anticancer compounds. This work serves as the foundation for further research and development of L. chinensis.


Asunto(s)
Alcaloides/uso terapéutico , Antineoplásicos Fitogénicos/uso terapéutico , Flavonoides/uso terapéutico , Lobelia/química , Neoplasias/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Alcaloides/farmacología , Animales , Antineoplásicos Fitogénicos/farmacología , Flavonoides/farmacología , Humanos , Extractos Vegetales/farmacología
8.
Ying Yong Sheng Tai Xue Bao ; 25(8): 2209-14, 2014 Aug.
Artículo en Zh | MEDLINE | ID: mdl-25509069

RESUMEN

The sap flow and environmental factors, including temperature, water content and water potential of soil, were continuously measured by using an auto-data collection system at the upper and lower slopes of Toona ciliata var. pubescens plantation in July to October, 2012 to investigate the relationships between the sap flow and environmental factors. The results showed that, the trunk sap flow velocity of the two positions both presented a typical single-peak curve, with high values in the daytime and low values in the nighttime. The average sap flow of the lower slope was significantly higher than that of the upper slope. Soil temperature of the upper slope was significantly higher than that of the lower slope, and soil water content and water potential were vice versa. Soil water content and water potential were the leading environmental factors affecting the trunk sap flow velocity at the lower slope, while soil temperature and water potential were the main environmental factors at the upper slope.


Asunto(s)
Meliaceae/fisiología , Tallos de la Planta/fisiología , Transpiración de Plantas , Ecosistema , Suelo , Temperatura , Agua
9.
Environ Geochem Health ; 29(5): 413-28, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17385049

RESUMEN

Micronutrient malnutrition is a major health problem in China. According to a national nutritional survey, approximately 24% of all Chinese children suffer from a serious deficiency of iron (Fe) (anemia), while over 50% show a sub-clinical level of zinc (Zn) deficiency. More than 374 million people in China suffer from goiter disease, which is related to iodine (I) deficiency, and approximately 20% of the Chinese population are affected by selenium (Se) deficiency. Micronutrient malnutrition in humans is derived from deficiencies of these elements in soils and foods. In China, approximately 40% of the total land area is deficient in Fe and Zn. Keshan and Kaschin-Beck diseases always appear in regions where the soil content of Se in low. The soil-plant system is instrumental to human nutrition and forms the basis of the "food chain" in which there is micronutrient cycling, resulting in an ecologically sound and sustainable flow of micronutrients. Soil-plant system strategies that have been adopted to improve human micronutrient nutrition mainly include: (1) exploiting micronutrient-dense crop genotypes by studying the physiology and genetics of micronutrient flow from soils to the edible parts of crops; (2) improving micronutrient bioavailability through a better knowledge of the mechanisms of the enhancers' production and accumulation in edible parts and its regulation through soil-plant system; (3) improving our knowledge of the relationship between the content and bioavailability of micronutrients in soils and those in edible crop products for better human nutrition; (4) developing special micronutrient fertilizers and integrated nutrient management technologies for increasing both the density of the micronutrients in the edible parts of plants and their bioavailability to humans.


Asunto(s)
Agricultura/métodos , Alimentos Fortificados , Micronutrientes , Trastornos Nutricionales/prevención & control , Desarrollo de la Planta , Suelo , Disponibilidad Biológica , Niño , China , Fertilizantes/análisis , Fertilizantes/normas , Geografía , Humanos , Hierro/metabolismo , Deficiencias de Hierro , Micronutrientes/deficiencia , Micronutrientes/metabolismo , Zinc/deficiencia , Zinc/metabolismo
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