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1.
Sci Rep ; 12(1): 22391, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575243

RESUMO

Karst regions are exceptionally responsive to global change with their harsh natural environment, fragile ecology, and acute human-land conflicts. The reconstruction of cropland spatial pattern in karst areas during the historical period is typical for studying human-land relations in karst areas and has important practical significance for climate study. The ecological environment changes at regional and global scales, primarily to provide essential data and a theoretical basis for studying the inverse evolution of rock desertification in karst areas. Guizhou province, a typical karst area, was selected as the research area in 1820. Based on the correction of historical population data and cropland data, a reconstruction model of cropland spatial pattern in karst areas during the historical period was constructed by selecting factors such as elevation, slope, soil types, organic matter content, climatic productivity potential, distance to river and distance from settlements to reconstruct the spatial pattern distribution of cropland in 1820 of Guizhou. The results show that the data on cropland recorded in Guizhou during the Qing dynasty is too low, mainly due to Yin-Ni and the policy of Tu-Di-Mian-Ke. In 1820, the total area of revised cropland in Guizhou was 1,851,792 hm2, with the highest proportion of 14.32% in Dading Fu and the lowest in Songtao Ting at 1.6%. Only 30% of the grid in Guizhou has a cropland distribution. It is mainly concentrated in the central part of Qianzhong District (Anshun and Guiyang Fu), the southern part of Qianbei District (Pingyue Fu and southern Zunyi Fu), the western part of Qiandongnan District, the central and eastern parts of the Qiandongbei District. The overall average reclamation rate of land in Guizhou is 10.93%, the highest reclamation intensity in Qianzhong District, with 8.5% of grids ≥ 50%, and the smallest in Qianxinan District, with only 1.65% of grids ≥ 50%. The analysis is validated by comparing the reconstruction model and the reconstruction results. It can be seen that the reconstruction model and research results of this paper can more objectively reflect the distribution of cropland in karst areas during the historical period, and the reconstruction model is suitable for karst areas with low productivity levels.


Assuntos
Ecossistema , Solo , Humanos , China , Ecologia , Produtos Agrícolas
2.
Sci Total Environ ; 810: 151209, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34748828

RESUMO

Vegetation changes in karst areas are controlled by the soil formation rate (SFR) and soil moisture (SM). However, little is known about their thresholds and global control patterns. To this end, based on high-precision climate and vegetation data for 2000-2014, using Pearson correlation analysis, the Hurst index, and change-point analysis, the thresholds of the SFR and SM in vegetation growth in karst areas were identified. Furthermore, a spatial map (0.125° × 0.125°) of the global karst ecosystem with a static/dynamic limitation zone was established. We found that the net primary productivity (NPP) in 70% of the global climate zones exhibited a dual restriction relationship with the SM and SFR. The limitations of the SFR and SM in vegetation growth were most obvious in subpolar and semi-arid climates. In addition, their ecological thresholds were 25.2 t km-2 yr-1 and 0.28 m3 m-3, respectively. The static limitation of the SFR on the NPP in karst areas accounted for 28.37%, and the influence of the SM enhanced this limit (21.79%). The limitation of the SFR on vegetation was mainly concentrated in Boreal forests (17%), and the limitation of the SM was mainly concentrated in tropical savannas (12%). The NPP and the Normalized Difference Vegetation Index (NDVI) were the most sensitive to changes in the SM and SFR. Moreover, the analysis based on 14 ecologically limitation karst areas further revealed that the reduction in these factors may cause the tropical rain forest to experience degradation. It can be seen that the SM enhanced the limiting effect of the SFR on vegetation in karst areas. In short, this interpretation of karst vegetation limitations provides a deeper understanding of and approach to ecosystem evolution and vegetation restoration in these regions.


Assuntos
Ecossistema , Solo , China , Clima Desértico
3.
Sci Total Environ ; 645: 460-470, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30029121

RESUMO

This work identifies the vegetation communities, landform types and seasons in which vegetation is most sensitive to water imbalance in the karst area of southwestern China. The normalized difference vegetation index (NDVI) and standardized precipitation and evapotranspiration index (SPEI) were used to evaluate the effects of water balance conditions on vegetation in different seasons and at different time scales. During the growing seasons from 1982 to 2013, the vegetation growth in 79% of the study area was statistically significantly sensitive to the water balance condition (p < 0.05). The vegetation in the spring and autumn responded more visibly to water imbalances. The SPEI over the last 6 months was statistically significantly correlated with the monthly maximum NDVI during the growing season over the larger areas compared with the SPEI over other time periods. Therefore, the vegetation was most likely sensitive to six months of water imbalance in this area. Among the selected vegetation types, the shrubland and sparse woodland were the most sensitive to water imbalances, whereas grasslands and forests were less sensitive. The maximum correlation coefficient between the NDVI and SPEI for each karst landform type was statistically significantly different (p < 0.01). The vegetation in the peak-cluster depressions was the most sensitive to water imbalances, whereas the vegetation in the middle and high karst mountains was the least sensitive to water imbalances. Overall, although the climate of the karst region of southwestern China is humid and subtropical, the vegetation is still vulnerable to water imbalances in particular regions and soils.


Assuntos
Monitoramento Ambiental/métodos , Tecnologia de Sensoriamento Remoto , China , Clima , Florestas
4.
Zhong Yao Cai ; 34(6): 971-4, 2011 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22017015

RESUMO

OBJECTIVE: To optimize the matrix formulation of compound Die Da Zhen Tong cataplasm. METHODS: The optimal preparation was selected by U17 (17(16)) uniform design, independent variables were the percentage ratio of the matrix formulation component part in compound Die Da Zhen Tong cataplasm,and the viscosity, continued viscosity and overall desirability used as indexes were dependent variables. RESULTS: The percentage of the matrix formulation component part in compound Die Da Zhen Tong cataplasm was, NP-700: carbomer 980: PVP K-90: dihydroxy aluminum: tartaric: kaolinite: sorbitol: glycerin = 5: 1. 2: 2.5: 0.25: 0.15:4: 12: 5. CONCLUSION: The optimized cataplasm has good viscosity, continued viscosity and high overall desirability.


Assuntos
Anti-Inflamatórios não Esteroides/química , Química Farmacêutica/métodos , Medicamentos de Ervas Chinesas/química , Plantas Medicinais/química , Adesividade , Administração Cutânea , Anti-Inflamatórios não Esteroides/administração & dosagem , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Concentração de Íons de Hidrogênio , Polipropilenos/administração & dosagem , Polipropilenos/química , Povidona/administração & dosagem , Povidona/química , Análise de Regressão , Tartaratos/administração & dosagem , Tartaratos/química , Viscosidade
5.
J Food Compost Anal ; 21(Suppl 1): S69-S77, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24307755

RESUMO

The Nutrient Data Laboratory of the United States Department of Agriculture (USDA) is collaborating with the Office of Dietary Supplements (ODS), the National Center for Health Statistics (NCHS), and other government agencies to design and populate a dietary supplement ingredient database (DSID). This analytically based, publicly available database will provide reliable estimates of vitamin and mineral content of dietary supplement (DS) products. The DSID will initially be populated with multivitamin/mineral (MVM) products because they are the most commonly consumed supplements. Challenges associated with the analysis of MVMs were identified and investigated. A pilot study addressing the identification of appropriate analytical methods, sample preparation protocols, and experienced laboratories for the analysis of 12 vitamins and 11 minerals in adult MVM supplement products was completed. Preliminary studies support the development of additional analytical studies with results that can be applied to the DSID. Total intakes from foods and supplements are needed to evaluate the associations between dietary components and health. The DSID will provide better estimates of actual nutrient intake from supplements than databases that rely on label values alone.

6.
J Food Compost Anal ; 21: S83-S93, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25346570

RESUMO

Although an estimated 50% of adults in the United States consume dietary supplements, analytically substantiated data on their bioactive constituents are sparse. Several programs funded by the Office of Dietary Supplements (ODS) at the National Institutes of Health enhance dietary supplement database development and help to better describe the quantitative and qualitative contributions of dietary supplements to total dietary intakes. ODS, in collaboration with the United States Department of Agriculture, is developing a Dietary Supplement Ingredient Database (DSID) verified by chemical analysis. The products chosen initially for analytical verification are adult multivitamin-mineral supplements (MVMs). These products are widely used, analytical methods are available for determining key constituents, and a certified reference material is in development. Also MVMs have no standard scientific, regulatory, or marketplace definitions and have widely varying compositions, characteristics, and bioavailability. Furthermore, the extent to which actual amounts of vitamins and minerals in a product deviate from label values is not known. Ultimately, DSID will prove useful to professionals in permitting more accurate estimation of the contribution of dietary supplements to total dietary intakes of nutrients and better evaluation of the role of dietary supplements in promoting health and well-being. ODS is also collaborating with the National Center for Health Statistics to enhance the National Health and Nutrition Examination Survey dietary supplement label database. The newest ODS effort explores the feasibility and practicality of developing a database of all dietary supplement labels marketed in the US. This article describes these and supporting projects.

7.
Anal Bioanal Chem ; 389(1): 231-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17676317

RESUMO

As part of a study initiating the development of an analytically validated Dietary Supplement Ingredient Database (DSID) in the United States (US), a selection of dietary supplement products were analyzed for their caffeine content. Products sold as tablets, caplets, or capsules and listing at least one caffeine-containing ingredient (including botanicals such as guarana, yerba mate, kola nut, and green tea extract) on the label were selected for analysis based on market share information. Two or three lots of each product were purchased and analyzed using high-pressure liquid chromatography (HPLC). Each analytical run included one or two National Institute of Standards and Technology (NIST) Standard Reference Materials (SRMs) and two products in duplicate. Caffeine intake per serving and per day was calculated using the maximum recommendations on each product label. Laboratory analysis for 53 products showed product means ranging from 1 to 829 mg caffeine/day. For products with a label amount for comparison (n = 28), 89% (n = 25) of the products had analytically based caffeine levels/day of between -16% and +16% of the claimed levels. Lot-to-lot variability (n = 2 or 3) for caffeine in most products (72%) was less than 10%.


Assuntos
Cafeína/análise , Suplementos Nutricionais/análise , Análise de Alimentos , Controle de Qualidade , Estados Unidos
8.
Anal Bioanal Chem ; 389(1): 37-46, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17641882

RESUMO

This article illustrates the importance of having analytical data on the vitamin and mineral contents of dietary supplements in nutrition studies, and describes efforts to develop an analytically validated dietary supplement ingredient database (DSID) by a consortium of federal agencies in the USA. Preliminary studies of multivitamin mineral supplements marketed in the USA that were analyzed as candidates for the DSID are summarized. Challenges are summarized, possible future directions are outlined, and some related programs at the Office of Dietary Supplements, National Institutes of Health are described. The DSID should be helpful to researchers in assessing relationships between intakes of vitamins and minerals and health outcomes.


Assuntos
Suplementos Nutricionais/análise , Minerais/análise , Ciências da Nutrição , Vitaminas/análise , Bases de Dados como Assunto , Humanos , Estados Unidos
9.
Nutr Cancer ; 54(1): 84-93, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16800776

RESUMO

The aim of the present study was to investigate the chemoprotective activity of anthocyanin-rich extracts (AREs) from bilberry (Vaccinium myrtillus L.), chokeberry (Aronia meloncarpa E.), and grape (Vitis vinifera) by assessing multiple biomarkers of colon cancer in male rats treated with a colon carcinogen, azoxymethane. Fischer 344 male rats were fed the AIN-93 diet (control) or AIN-93 diet supplemented with AREs for 14 wk. Biomarkers that were evaluated included the number and multiplicity of colonic aberrant crypt foci (ACF), colonic cell proliferation, urinary levels of oxidative DNA damage, and expression of cyclooxygenase (COX) genes. To assess the bioavailability, levels of anthocyanins in serum, urine, and feces were evaluated. Total ACF were reduced (P<0.05) in bilberry, chokeberry, and grape diet groups compared with the control group. The number of large ACF was also reduced (P<0.05) in bilberry and chokeberry ARE-fed rats. Colonic cellular proliferation was decreased in rats fed bilberry ARE and chokeberry ARE diets. Rats fed bilberry and grape ARE diets had lower COX-2 mRNA expression of gene. High levels of fecal anthocyanins and increased fecal mass and fecal moisture occurred in ARE-fed rats. There was also a significant reduction (P<0.05) in fecal bile acids in ARE-fed rats. The levels of urinary 8-hydroxyguanosine were similar among rats fed different diets. These results support our previous in vitro studies suggesting a protective role of AREs in colon carcinogenesis and indicate multiple mechanisms of action.


Assuntos
Antocianinas/administração & dosagem , Biomarcadores/análise , Neoplasias do Colo/prevenção & controle , Frutas/química , Extratos Vegetais/administração & dosagem , 8-Hidroxi-2'-Desoxiguanosina/análogos & derivados , Animais , Antocianinas/análise , Antocianinas/farmacocinética , Ácidos e Sais Biliares/análise , Disponibilidade Biológica , Peso Corporal , Divisão Celular/efeitos dos fármacos , Colo/patologia , Neoplasias do Colo/patologia , Ciclo-Oxigenase 2/genética , Ingestão de Alimentos , Fezes/química , Guanina/análogos & derivados , Guanina/urina , Masculino , Fitoterapia , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos F344 , Rosaceae/química , Organismos Livres de Patógenos Específicos , Vaccinium myrtillus/química , Vitis/química , Água/análise
10.
J Food Compost Anal ; 19: S108-S114, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25309034

RESUMO

Several activities of the Office of Dietary Supplements (ODS) at the National Institutes of Health involve enhancement of dietary supplement databases. These include an initiative with US Department of Agriculture to develop an analytically substantiated dietary supplement ingredient database (DSID) and collaboration with the National Center for Health Statistics to enhance the dietary supplement label database in the National Health and Nutrition Examination Survey (NHANES). The many challenges that must be dealt with in developing an analytically supported DSID include categorizing product types in the database, identifying nutrients, and other components of public health interest in these products and prioritizing which will be entered in the database first. Additional tasks include developing methods and reference materials for quantifying the constituents, finding qualified laboratories to measure the constituents, developing appropriate sample handling procedures, and finally developing representative sampling plans. Developing the NHANES dietary supplement label database has other challenges such as collecting information on dietary supplement use from NHANES respondents, constant updating and refining of information obtained, developing default values that can be used if the respondent cannot supply the exact supplement or strength that was consumed, and developing a publicly available label database. Federal partners and the research community are assisting in making an analytically supported dietary supplement database a reality.

11.
Zhong Yao Cai ; 28(7): 599-601, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16252731

RESUMO

OBJECTIVE: To optimize the best extracting procedure for Radix Panacis Quinquefolii. METHODS: (1) The optimum alcohol extracting procedure was selected with the content and extraction efficiency of ginsenoside Rg, Re, Rb, from Radix Panacis Quinquefolii by orthogonal test design and synthesizing multiple guidelines method. (2) The content of three ginsenoides Rg1, Re and Rb1 in Radix Panacis Quinquefolii was determined by gradient elution method in RP-HPLC. RESULTS: The optimum alcohol-extracting procedure was determined as 12 times of 70% alcohol refluxing and extracting 3 h for 2 times. CONCLUSIONS: The optimum extracting procedure can increase extraction efficiency of Radix Panacis Quinquefolii.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Ginsenosídeos/isolamento & purificação , Panax/química , Plantas Medicinais/química , Tecnologia Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Etanol , Ginsenosídeos/análise , Raízes de Plantas/química , Controle de Qualidade , Tempo
12.
J Agric Food Chem ; 52(20): 6122-8, 2004 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-15453676

RESUMO

Commercially prepared grape (Vitis vinifera), bilberry (Vaccinium myrtillus L.), and chokeberry (Aronia meloncarpa E.) anthocyanin-rich extracts (AREs) were investigated for their potential chemopreventive activity against colon cancer. The growth of colon-cancer-derived HT-29 and nontumorigenic colonic NCM460 cells exposed to semipurified AREs (10-75 microg of monomeric anthocyanin/mL) was monitored for up to 72 h using a sulforhodamine B assay. All extracts inhibited the growth of HT-29 cells, with chokeberry ARE being the most potent inhibitor. HT-29 cell growth was inhibited approximately 50% after 48 h of exposure to 25 microg/mL chokeberry ARE. Most importantly, the growth of NCM460 cells was not inhibited at lower concentrations of all three AREs, illustrating greater growth inhibition of colon cancer, as compared to nontumorigenic colon cells. Extracts were semipurified and characterized by high-pressure liquid chromatography, spectrophotometry, and colorimetry. Grape anthocyanins were the glucosylated derivatives of five different anthocyanidin molecules, with or without p-coumaric acid acylation. Bilberry contained five different anthocyanidins glycosylated with galactose, glucose, and arabinose. Chokeberry anthocyanins were cyanidin derivatives, monoglycosylated mostly with galactose and arabinose. The varying compositions and degrees of growth inhibition suggest that the anthocyanin chemical structure may play an important role in the growth inhibitory activity of commercially available AREs.


Assuntos
Antocianinas/análise , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Extratos Vegetais/farmacologia , Anticarcinógenos/farmacologia , Frutas/química , Humanos , Fenóis/análise , Rosaceae/química , Células Tumorais Cultivadas , Vaccinium myrtillus/química , Vitis/química
13.
Nutr Cancer ; 46(2): 186-96, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14690795

RESUMO

Anthocyanin-rich extracts, potent antioxidants and commercially available food coloring agents, have been reported to inhibit growth of various cancer cell lines. We investigated the effect of semipurified anthocyanin-rich extract from fruits of Aronia meloncarpa, on normal colon and colon cancer cell lines. A 24-h exposure to 50 mg monomeric anthocyanin/ml of Aronia extract resulted in 60% growth inhibition of human HT-29 colon cancer cells. The treated cells showed a blockage at G1/G0 and G2/M phases of the cell cycle. The cell cycle arrest coincided with an increased expression of the p21WAF1 and p27KIP1 genes and decreased expression of cyclin A and B genes. Prolonged exposure to the extract resulted in no further change in the cell number, indicating a cytostatic inhibition of cell growth. NCM460 normal colon cells demonstrated <10% growth inhibition at the highest concentration of 50 mg/ml extract. A 35% decrease in the cyclooxygenase-2 gene expression was observed within 24 h of exposure of HT-29 cells but did not translate into decreased protein levels or protein activity. These results support the need for further research to identify the specific component(s) in this extract that suppress cancer cell growth and the genes affected by these natural compounds.


Assuntos
Antocianinas/análise , Antocianinas/farmacologia , Ciclo Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Extratos Vegetais/farmacologia , Rosaceae/química , Proteínas de Ciclo Celular/genética , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Colo/química , Colo/patologia , Inibidor de Quinase Dependente de Ciclina p21 , Inibidor de Quinase Dependente de Ciclina p27 , Ciclinas/genética , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Expressão Gênica/efeitos dos fármacos , Humanos , Isoenzimas/genética , Proteínas de Membrana , Extratos Vegetais/química , Prostaglandina-Endoperóxido Sintases/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor/genética
14.
Emerg Infect Dis ; 8(12): 1409-14, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12498656

RESUMO

Susceptibilities to fourteen antimicrobial agents important in clinical medicine and agriculture were determined for 752 Escherichia coli isolates of serotypes O26, O103, O111, O128, and O145. Strains of these serotypes may cause urinary tract and enteric infections in humans and have been implicated in infections with Shiga toxin-producing E. coli (STEC). Approximately 50% of the 137 isolates from humans were resistant to ampicillin, sulfamethoxazole, cephalothin, tetracycline, or streptomycin, and approximately 25% were resistant to chloramphenicol, trimethoprim-sulfamethoxazole, or amoxicillin-clavulanic acid. Approximately 50% of the 534 isolates from food animals were resistant to sulfamethoxazole, tetracycline, or streptomycin. Of 195 isolates with STEC-related virulence genes, approximately 40% were resistant to sulfamethoxazole, tetracycline, or streptomycin. Findings from this study suggest antimicrobial resistance is widespread among E. coli O26, O103, O111, O128, and O145 inhabiting humans and food animals.


Assuntos
Farmacorresistência Bacteriana , Escherichia coli O157 , Animais , Escherichia coli O157/classificação , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/genética , Escherichia coli O157/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Sorotipagem
15.
Appl Environ Microbiol ; 68(2): 576-81, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11823193

RESUMO

A total of 361 Escherichia coli O157 isolates, recovered from humans, cattle, swine, and food during the years 1985 to 2000, were examined to better understand the prevalence of antimicrobial resistance among these organisms. Based on broth microdilution results, 220 (61%) of the isolates were susceptible to all 13 antimicrobials tested. Ninety-nine (27%) of the isolates, however, were resistant to tetracycline, 93 (26%) were resistant to sulfamethoxazole, 61 (17%) were resistant to cephalothin, and 48 (13%) were resistant to ampicillin. Highest frequencies of resistance occurred among swine isolates (n = 70), where 52 (74%) were resistant to sulfamethoxazole, 50 (71%) were resistant to tetracycline, 38 (54%) were resistant to cephalothin, and 17 (24%) were resistant to ampicillin. Based on the presence of Shiga toxin genes as determined by PCR, 210 (58%) of the isolates were identified as Shiga toxin-producing E. coli (STEC). Among these, resistance was generally low, yet 21 (10%) were resistant to sulfamethoxazole and 19 (9%) were resistant to tetracycline. Based on latex agglutination, 189 (52%) of the isolates were identified as E. coli O157:H7, among which 19 (10%) were resistant to sulfamethoxazole and 16 (8%) were resistant to tetracycline. The data suggest that selection pressure imposed by the use of tetracycline derivatives, sulfa drugs, cephalosporins, and penicillins, whether therapeutically in human and veterinary medicine or as prophylaxis in the animal production environment, is a key driving force in the selection of antimicrobial resistance in STEC and non-STEC O157.


Assuntos
Doenças dos Bovinos/microbiologia , Farmacorresistência Bacteriana , Escherichia coli O157/efeitos dos fármacos , Carne/microbiologia , Doenças dos Suínos/microbiologia , Animais , Antibacterianos/farmacologia , Bovinos , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli O157/classificação , Escherichia coli O157/isolamento & purificação , Microbiologia de Alimentos , Humanos , Testes de Sensibilidade Microbiana , Sorotipagem , Toxina Shiga/metabolismo , Suínos
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