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1.
J Environ Manage ; 299: 113676, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34526275

RESUMO

During the past few decades, commercial silvopastoral systems (SPS) with exotic Eucalyptus (hybrid) trees have become popular in the Brazilian Cerrado (savanna). With the increasing awareness about the role of carbon (C) storage in soils as a climate-change mitigation strategy and the relationship between the nature of soil aggregates and the soil's carbon sequestration potential, it is important to understand the influence of such SPS systems on soil organic carbon (SOC) storage. We studied C content in three aggregate size classes in six land-use systems on Oxisols in Minas Gerais, Brazil. The systems were planted forest, native secondary forest, managed pasture, and three 8-year-old SPS, differing in their tree-planting configurations. Eucalyptus hybrid was the tree in SPS and planted forest treatments, and Urochloa decumbens was the grass in SPS and pasture treatments. From each treatment, replicated soil samples were collected from four depth-classes (0-10, 10-30, 30-60, and 60-100 cm), fractionated by wet sieving into the three aggregate-size classes, 2000 to 250 µm, 250 to 53 µm, and <53 µm size classes representing macroaggregates, microaggregates, and silt + clay, respectively, and their C contents determined. Down to 1 m, total SOC stock values ranged from 260 Mg ha-1 under pasture to 167 Mg ha-1 under native forest, with 174 Mg ha-1 for Eucalyptus plantation and about 195 Mg ha-1 for the three SPS. Compared to the degraded native forest, the pasture system had significantly higher SOC in the whole soil and the aggregate size fractions, especially in the lower soil-depth classes. The lower SOC stock of Eucalyptus hybrid SPS compared to open pasture differs from the general trend of SPS having higher stock. Given that the Cerrado biome is a biodiversity hotspot, the use of native nitrogen-fixing trees, of which there are several, is worth investigating. In addition, the conversion from Eucalyptus monocultures to SPS could be considered as a strategy to increase the SOC stock.


Assuntos
Eucalyptus , Solo , Agricultura , Biodiversidade , Carbono , Sequestro de Carbono
2.
Sci Rep ; 11(1): 10051, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980878

RESUMO

Solar drying is a sustainable process that may impact the quality of dried food. This is because, pigments contained in food are sensitive to sunlight, and exposure to ultraviolet radiation can affect them. We applied biopolymer-based coatings on strawberry, from hydro-colloidal solutions of Opuntia ficus indica-mucilage, fenugreek, xanthan gum, gum Arabic, and guar gum to evaluate their potential use as UV filters for solar drying of food. Thermal properties and the optical transmittance, absorbance and reflectance of the coatings were measured to assess their influence on food-sunlight interaction. During the drying experiments, the moisture content, total anthocyanins (TA), and total phenolic compounds (TPC) were measured. Optical and thermal properties are influenced by the biopolymer-based coatings. Also, the optical properties are influenced by the coating thickness. The differences in optical and thermal properties influence the drying process. Differences exist in the drying rate for strawberry slices with coating, compared with those without the coatings. In general, the TA and TPC content in the product are better preserved under solar drying than in control experiments done in a drying oven. A partial transmittance of solar UV radiation is recommended to obtain increased TA and TPC contents in the dried product.

3.
Front Plant Sci ; 8: 2051, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29312364

RESUMO

Interest in the use of biochar in agriculture has increased exponentially during the past decade. Biochar, when applied to soils is reported to enhance soil carbon sequestration and provide other soil productivity benefits such as reduction of bulk density, enhancement of water-holding capacity and nutrient retention, stabilization of soil organic matter, improvement of microbial activities, and heavy-metal sequestration. Furthermore, biochar application could enhance phosphorus availability in highly weathered tropical soils. Converting the locally available feedstocks and farm wastes to biochar could be important under smallholder farming systems as well, and biochar use may have applications in tree nursery production and specialty-crop management. Thus, biochar can contribute substantially to sustainable agriculture. While these benefits and opportunities look attractive, several problems, and bottlenecks remain to be addressed before widespread production and use of biochar becomes popular. The current state of knowledge is based largely on limited small-scale studies under laboratory and greenhouse conditions. Properties of biochar vary with both the feedstock from which it is produced and the method of production. The availability of feedstock as well as the economic merits, energy needs, and environmental risks-if any-of its large-scale production and use remain to be investigated. Nevertheless, available indications suggest that biochar could play a significant role in facing the challenges posed by climate change and threats to agroecosystem sustainability.

4.
J Environ Monit ; 13(7): 1897-904, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21643613

RESUMO

The extent of carbon (C) stored in soils depends on a number of factors including soil characteristics, climatic and other environmental conditions, and management practices. Such information, however, is lacking for silvopastoral systems in Spain. This study quantified the amounts of soil C stored at various depths (0-25, 25-50, 50-75, and 75-100 cm) under a Dehesa cork oak (Quercus suber L.) silvopasture at varying distances (2, 5, and 15 m) to trees. Soil C in the whole soil and three soil fractions (<53, 53-250, and 250-2000 µm) was determined. Results showed soil depth to be a significant factor in soil C stocks in all soil particle sizes. Distance to tree was a significant factor determining soil C stocks in the whole soil and the 250-2000 µm soil fraction. To 1 m depth, mean total C storage at 2, 5, and 15 m from cork oak was 50.2, 37, and 26.5 Mg ha(-1), respectively. Taking into account proportions of land surface area containing these C stocks at varying distances to trees to 1 m depth, with a tree density of 35 stems ha(-1), estimated landscape soil C is 29.9 Mg ha(-1). Greater soil C stocks directly underneath the tree canopy suggest that maintaining or increasing tree cover, where lost from disease or management, may increase long term storage of soil C in Mediterranean silvopastoral systems. The results also demonstrate the use of soil aggregate characteristics as better indicators of soil C sequestration potential and thus a tool for environmental monitoring.


Assuntos
Sequestro de Carbono , Carbono/análise , Quercus/crescimento & desenvolvimento , Poluentes do Solo/análise , Solo/química , Agricultura , Monitoramento Ambiental , Espanha
5.
J Environ Qual ; 40(3): 784-90, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21546663

RESUMO

Investments in agroforestry research during the past three decades-albeit modest-have yielded significant gains in understanding the role of trees on farmlands, and the ecological and economic advantages of integrated farming systems. While early research focused mostly on farm or local levels, broader-level ecosystem services of agroforestry systems (AFS) have raised high expectations in recent years. The nine papers included in this special collection deal with three of such environmental benefits of AFS: water-quality enhancement, carbon sequestration, and soil improvement. These benefits are based on the perceived ability of (i) vegetative buffer strips (VBS) to reduce surface transport of agrochemical pollutants, (ii) large volumes of aboveground and belowground biomass of trees to store high amounts of C deeper in the soil profile, and (iii) trees to enhance soil productivity through biological nitrogen fixation, efficient nutrient cycling, and deep capture of nutrients. The papers included have, in general, substantiated these premises and provided new insights. For example, the riparian VBS are reported to increase the reservoir life, in addition to reducing transport of agrochemicals; the variations in C storage in different soil-fraction sizes suggest that microaggregate (250-53 µm) dynamics in the soil could be a good indicator of its C-storage potential; and the use of vector analysis technique is recommended in AFS to avoid consequences of inaccurate and overuse of fertilizers. The papers also identified significant knowledge gaps in these areas. A common theme across all three environmental quality issues covered is that more and varied research datasets across a broad spectrum of conditions need to be generated and integrated with powerful statistical tools to ensure wide applicability of the results. Furthermore, appropriate management practices that are acceptable to the targeted land users and agroforestry practitioners need to be designed to exploit these environmental benefits. The relative newness of research in environmental quality of AFS will pose some additional challenges as well. These include the lack of allometric equations for tree-biomass determination, absence of standardized norms on soil sampling depth, and limitations of fixed-effect models arising from issues such as pseudo-replication and repeated measures that are common in studies on preexisting field plots. Overall, this special collection is a timely effort in highlighting the promise of AFS in addressing some of the environmental quality issues, and the challenges in realizing that potential.


Assuntos
Meio Ambiente , Recuperação e Remediação Ambiental/métodos , Agricultura Florestal/métodos , Sequestro de Carbono , Conservação dos Recursos Naturais/métodos , Solo/química , Árvores/crescimento & desenvolvimento , Abastecimento de Água
6.
J Environ Qual ; 40(3): 833-41, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21546669

RESUMO

Silvopastoral management of fast-growing tree plantations is becoming popular in the Brazilian Cerrado (savanna). To understand the influence of such systems on soil carbon (C) storage, we studied C content in three aggregate size classes in six land-use systems (LUS) on Oxisols in Minas Gerais, Brazil. The systems were a native forest, a treeless pasture, 24- and 4-yr-old eucalyptus ( sp.) plantations, and 15- and 4-yr-old silvopastures of fodder grass plus animals under eucalyptus. From each system, replicated soil samples were collected from four depths (0-10, 10-20, 20-50, and 50-100 cm), fractionated into 2000- to 250-, 250- to 53-, and <53-µm size classes representing macroaggregates, microaggregates, and silt + clay, respectively, and their C contents determined. Macroaggregate was the predominant size fraction under all LUS, especially in the surface soil layers of tree-based systems. In general, C concentrations (g kg soil) in the different aggregate size fractions did not vary within the same depth. The soil organic carbon (SOC) stock (Mg C ha) to 1-m depth was highest under pasture compared with other LUS owing to its higher soil bulk density. The soils under all LUS had higher C stock compared with other reported values for managed tropical ecosystems: down to 1 m, total SOC stock values ranged from 461 Mg ha under pasture to 393 Mg ha under old eucalyptus. Considering the possibility for formation and retention of microaggregates within macroggregates in low management-intensive systems such as silvopasture, the macroaggregate dynamics in the soil seem to be a good indicator of its C storage potential.


Assuntos
Agricultura , Sequestro de Carbono , Carbono/análise , Agricultura Florestal , Tamanho da Partícula , Solo/análise , Animais , Brasil , Monitoramento Ambiental , Eucalyptus/crescimento & desenvolvimento , Fertilizantes , Gado , Poaceae
7.
J Environ Qual ; 40(3): 825-32, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21546668

RESUMO

Soil particle size and land management practices are known to have considerable influence on carbon (C) storage in soils, but such information is lacking for silvopastoral systems in Spain. This study quantified the amounts of soil C stored at various depths to 100 cm under silvopastoral plots of radiata pine ( D. Don) and birch ( Roth) in comparison to treeless pasture in Galicia, Spain. Soils were fractionated into three size classes (<53, 53-250, and 250-2000 µm), and C stored in them and in the whole (nonfractionated) soil was determined. Overall, the C stock to 1 m ranged from 80.9 to 176.9 Mg ha in these soils. Up to 1 m depth, 78.82% of C was found in the 0- to 25-cm soil depth, with 12.9, 4.92, and 3.36% in the 25- to 50-, 50- to 75-, and 75- to 100-cm depths, respectively. Soils under birch at 0 to 25 cm stored more C in the 250- to 2000-µm size class as compared with those under radiata pine; at that depth, pasture had more C than pine silvopasture in the smaller soil fractions (<53 and 53-250 µm). In the 75- to 100-cm depth, there was significantly more storage of C in the 250- to 2000-µm fraction in both silvopastures as compared with the pasture. The higher storage of soil C in larger fraction size in lower soil depths of silvopasture suggests that planting of trees into traditional agricultural landscapes will promote longer-term storage of C in the soil.


Assuntos
Agricultura , Sequestro de Carbono , Carbono/análise , Tamanho da Partícula , Solo/análise , Betula/crescimento & desenvolvimento , Monitoramento Ambiental , Fertilizantes , Pinus/crescimento & desenvolvimento , Espanha , Especificidade da Espécie , Árvores/crescimento & desenvolvimento
8.
Environ Manage ; 45(2): 274-83, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20069301

RESUMO

Shaded perennial agroforestry systems contain relatively high quantities of soil carbon (C) resulting from continuous deposition of plant residues; however, the extent to which the C is sequestered in soil will depend on the extent of physical protection of soil organic C (SOC). The main objective of this study was to characterize SOC storage in relation to soil fraction-size classes in cacao (Theobroma cacao L.) agroforestry systems (AFSs). Two shaded cacao systems and an adjacent natural forest in reddish-yellow Oxisols in Bahia, Brazil were selected. Soil samples were collected from four depth classes to 1 m depth and separated by wet-sieving into three fraction-size classes (>250 microm, 250-53 microm, and <53 microm)-corresponding to macroaggregate, microaggregate, and silt-and-clay size fractions-and analyzed for C content. The total SOC stock did not vary among systems (mean: 302 Mg/ha). On average, 72% of SOC was in macroaggregate-size, 20% in microaggregate-size, and 8% in silt-and-clay size fractions in soil. Sonication of aggregates showed that occlusion of C in soil aggregates could be a major mechanism of C protection in these soils. Considering the low level of soil disturbances in cacao AFSs, the C contained in the macroaggregate fraction might become stabilized in the soil. The study shows the role of cacao AFSs in mitigating greenhouse gas (GHG) emission through accumulation and retention of high amounts of organic C in the soils and suggests the potential benefit of this environmental service to the nearly 6 million cacao farmers worldwide.


Assuntos
Agricultura , Cacau , Carbono/análise , Agricultura Florestal , Solo/análise , Brasil
9.
J Ethnopharmacol ; 122(3): 450-6, 2009 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-19429311

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The fruits and seeds of Semecarpus anacardium are used widely for the treatment of human cancers and other diseases in the Ayurvedic and Sidda systems of medicine in India. AIM OF THE STUDY: The principal aim of this investigation was to isolate and characterize the anticancer compound from the kernel of Semecarpus anacardium nut. MATERIALS AND METHODS: The bioactivity-tailored isolation and detailed chemical characterization were used to identify the active compound. Cytotoxicity, apoptosis, cell cycle arrest as well as synergism between the identified anticancer compound and doxorubicin in human tumor cell lines were analyzed. RESULTS: GC/MS, IR, proton NMR, carbon NMR and collisionally induced dissociation (CID) spectra analysis showed that the isolated active compound is 3-(8'(Z),11'(Z)-pentadecadienyl) catechol (SA-3C). SA-3C is cytotoxic to tumor cell lines with IC(50) values lower than doxorubicin and even multidrug resistant tumor cell lines were equally sensitive to SA-3C. SA-3C induced apoptosis in human leukemia cell lines in a dose-dependent manner and showed synergistic cytotoxicity with doxorubicin. The cell cycle arrest induced by SA-3C at S- and G(2)/M-phases correlated with inhibition of checkpoint kinases. CONCLUSION: SA-3C isolated from the kernel of Semecarpus anacardium can be developed as an important anticancer agent for single agent and/or multiagent cancer therapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Catecóis/isolamento & purificação , Doxorrubicina/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Semecarpus/química , Antibióticos Antineoplásicos/uso terapêutico , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Catecóis/química , Catecóis/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/uso terapêutico , Sinergismo Farmacológico , Humanos , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Proteínas Quinases/metabolismo , Sementes
10.
J Environ Qual ; 37(5): 1789-97, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18689740

RESUMO

Compared with open (treeless) pasture systems, silvopastoral agroforestry systems that integrate trees into pasture production systems are likely to enhance soil carbon (C) sequestration in deeper soil layers. To test this hypothesis, total soil C contents at six soil depths (0-5, 5-15, 15-30, 30-50, 50-75, and 75-125 cm) were determined in silvopastoral systems with slash pine (Pinus elliottii) + bahiagrass (Paspalum notatum) and an adjacent open pasture (OP) with bahiagrass at four sites, representing Spodosols and Ultisols, in Florida. Soil samples from each layer were fractionated into three classes (250-2000, 53-250, and <53 microm), and the C contents in each were determined. Averaged across four sites and all depths, the total soil organic carbon (SOC) content was higher by 33% in silvopastures near trees (SP-T) and by 28% in the alleys between tree rows (SP-A) than in adjacent open pastures. It was higher by 39% in SP-A and 20% in SP-T than in open pastures in the largest fraction size (250-2000 microm) and by 12.3 and 18.8%, respectively, in the intermediate size fraction (53-250 microm). The highest SOC increase (up to 45 kg m(-2)) in whole soil of silvopasture compared with OP was at the 75- to 125-cm depth at the Spodosol sites. The results support the hypothesis that, compared with open pastures, silvopastures contain more C in deeper soil layers under similar ecological settings, possibly as a consequence of a major input to soil organic matter from decomposition of dead tree-roots.


Assuntos
Agricultura , Carbono/química , Solo/análise , Florida , Tamanho da Partícula
11.
Anticancer Res ; 28(2A): 965-71, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18507043

RESUMO

Annona glabra (pond apple), a tropical tree growing wild in the Americas and Asia, is used in traditional medicine against several human ailments, including cancer. To validate the ethnopharmacological claims against cancer, the anticancer effects of alcoholic extracts prepared from pond apple leaves, pulp and seed, were investigated in human leukemia cell lines. The alcoholic extracts were not cytotoxic to normal human lymphocytes. However, extracts were highly cytotoxic to drug sensitive (CEM) and multidrug-resistant leukemia (CEM/VLB) cell lines. The seed extract was more potent than leaf and pulp extracts, and the cytotoxicity values were significantly lower than that for adriamycin. The seed extract caused a concentration-dependent increase in the percentage of the sub G0/G1, as well as G0/G1 cell population, contributing to the cytotoxicity. The sub G0/G1 population increased from 2.2 to 7.0% in CEM and from 1.0 to 10.7% in CEM/VLB cell lines, when the cells were treated with 0-10 Bg/ml seed extract. Treatment of CEM and CEM/VLB cells with seed extract induced apoptosis and necrosis in both sensitive and resistant leukemia cells in a concentration-dependent manner. The seed extract at 2 and 5 Bg/ml enhanced cellular daunorubicin accumulation, indicating the competitive P-glycoprotein binding ability and drug-resistance reversal effect. Treatment of CEM and CEM/VLB cells with seed extracts also up-regulated the expression of cyclin kinase inhibitor (WAF1/p21) contributing to the arrest of cells at the G0/G1 phase of the cell cycle. These results support the traditional use of A. glabra and the alcoholic seed extract is a potent source of anticancer compounds that could be utilized pharmaceutically.


Assuntos
Annona/química , Antineoplásicos/uso terapêutico , Leucemia/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Apoptose/efeitos dos fármacos , Ciclo Celular , Linhagem Celular Tumoral , Daunorrubicina/farmacocinética , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Fitoterapia
12.
Int J Tuberc Lung Dis ; 11(7): 755-61, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17609050

RESUMO

BACKGROUND: Little is known yet about the cost-effectiveness of public-private mix (PPM) collaborations for the delivery of tuberculosis (TB) diagnostic and treatment services. DESIGN: We evaluated the cost and cost-effectiveness of a PPM project targeting private laboratories in Kannur district, India, from the perspective of the Revised National TB Control Programme (RNTCP). We estimated the cost per provider recruited and retained, the cost per additional patient notified under various effectiveness scenarios and the cost per additional patient successfully treated. Intervention cost data were abstracted from RNTCP records. Treatment costs were estimated based on RNTCP case management protocols. RESULTS: The annual total estimated cost of the project was US$8712-$11611. The cost per private provider recruited varied between US$22 and US$54. The cost per additional pulmonary TB patient privately diagnosed was US$14-$18. In the most conservative scenario, the cost per additional patient notified was US$29-$36. The cost per new acid-fast bacilli-positive patient successfully treated was US$47-$51. Higher notification rates would improve cost-effectiveness. CONCLUSIONS: Comparisons with public sector diagnostic costs are required to determine if this intervention remains economically attractive to the public health care system at different activity levels and to determine the supplemental resources needed if scale-up is pursued.


Assuntos
Controle de Doenças Transmissíveis/economia , Efeitos Psicossociais da Doença , Programas Nacionais de Saúde/organização & administração , Parcerias Público-Privadas/organização & administração , Tuberculose Pulmonar/economia , Análise Custo-Benefício , Custos e Análise de Custo , Países em Desenvolvimento , Feminino , Organização do Financiamento/economia , Humanos , Índia , Masculino , Avaliação de Programas e Projetos de Saúde , Sistema de Registros , Estudos Retrospectivos , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/terapia
13.
J Altern Complement Med ; 13(4): 403-7, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17532732

RESUMO

BACKGROUND: The efficacy of homeopathic medicines for maintaining human health and treating disease has been extensively examined in clinical trials. However, there is a paucity of preclinical evaluations of the effects of homeopathic medicinal preparations on cellular signaling pathways relevant to the applications of these preparations. MATERIALS AND METHODS: In this study, the immune-modulatory effects of Phase 6 (for the stimulation of the nonspecific defense system) and Flu Terminator (for influenza and viral diseases) (Be Well Homeopathics Inc. Miami, FL), two homeopathic preparations developed for the purpose, were evaluated in normal human leukocyte cultures in vitro. RESULTS: Both Phase 6 and Flu Terminator stimulated the production of pro-and anti-inflammatory cytokines by human leukocytes, although higher doses often produced a weaker response than lower doses. The carrier solvent (20% ethanol) failed to elicit any cytokine synthesis. CONCLUSIONS: The results of the in vitro studies suggested that ultralow concentrations of ingredients in Phase 6 and Flu Terminator were capable of eliciting a human immune response.


Assuntos
Citocinas/efeitos dos fármacos , Homeopatia , Mediadores da Inflamação/farmacologia , Leucócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Análise de Variância , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Humanos , Técnicas In Vitro , Interleucina-1/metabolismo , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Leucócitos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
14.
Int Immunopharmacol ; 6(12): 1815-24, 2006 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-17052672

RESUMO

The signaling mechanism of the novel (1,4)-alpha-D-glucan (RR1) isolated from the medicinal plant Tinospora cordifolia was investigated in macrophages to evaluate its immunostimulating properties. When RAW264.7 macrophages were incubated with RR1 at 4 degrees C, the novel glucan inhibited the phagocytosis of unopsonized zymosan A bioparticles in a dose-dependent manner. RR1 also inhibited the binding and internalization of opsonized zymosan A bioparticles, although at a lower level than laminarin. Incubation of macrophages with anti-CD11b mAb followed by RR1 failed to show any inhibitory effect on RR1-induced TNF-alpha synthesis confirming that complement receptor 3 (CR3) is not involved in the opsonic binding and internalization of RR1 in macrophages unlike zymosan A. The anti-CD11b mAb has significant inhibitory effect on the zymosan A-induced tumor necrosis factor (TNF)-alpha synthesis. RR1 induced TNF-alpha synthesis in macrophages in a dose-dependent manner which can be completely inhibited by the NF-kappaB inhibitor caffeic acid phenethyl ester (CAPE) or curcumin. RR1 activated NF-kappaB in a time- and dose-dependent manner and this modulation of nuclear NF-kappaB activity is associated with the degradation of I-kappaB alpha thus facilitating the translocation of NF-kappaB into the nucleus. RR1-induced NF-kappaB activity peaks at 8 h of RR1 stimulation while I-kappaB alpha degradation occurred within 1 h of stimulation. RR1-induced NF-kappaB activation occurred through TLR6 signaling as evidenced by the synthesis of IL-8 in TLR6-transfected HEK293 cells. These results show that the novel (1,4)-alpha-D-glucan from Tinospora cordifolia activates the immune system through the activation of macrophages that occurs through TLR6 signaling, NF-kappaB translocation and cytokine production.


Assuntos
Glucanos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , NF-kappa B/imunologia , Receptor 6 Toll-Like/imunologia , Animais , Linhagem Celular , Humanos , Proteínas I-kappa B/imunologia , Antígeno de Macrófago 1/imunologia , Camundongos , Inibidor de NF-kappaB alfa , Fagocitose/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Tinospora/química , Fator de Necrose Tumoral alfa/imunologia
15.
Int J Cancer ; 119(10): 2443-54, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16894569

RESUMO

Amooranin (AMR), a natural triterpenoid drug isolated and characterized from Amoora rohituka stem bark, is cytotoxic to SW620 human colon carcinoma cell line with an IC(50) value of 2.9 microg/ml. This novel compound caused depolarization of mitochondrial membrane and decrease of membrane potential, indicating initial signal of apoptosis induction. The percentage of cells with decreased mitochondrial potential ranged from 7.4% at 1 microg/ml to 60.5% at 100 microg/ml AMR. Flow cytometric analysis of apoptosis using Annexin-V-FITC staining showed that the percentage of apoptotic cells ranged from 7.5% at 1 microg/ml to 59.2% at 100 microg/ml AMR. AMR-induced apoptosis was accompanied by redistribution of cytochrome c from mitochondria to cytosol as well as down regulation of Bcl-2 and Bcl-X(L) proteins in a dose-dependent manner. SW620 human colon carcinoma xenograft mice treated with AMR showed significant reduction in tumor growth rates compared to saline- and doxorubicin-treated groups. The reduction in tumor growth rate was better in xenografts treated with 2 mg/kg AMR than 5 and 10 mg/kg treated mice. The analysis of global gene expression changes induced by AMR in xenograft tumors by microarray hybridization revealed that several genes involved in energy pathways, transport, apoptosis, immune response, nucleic acid metabolism, protein metabolism, cell growth and/or maintenance, signal transduction and cell communication, were affected by this natural cancer drug. These results suggest that the anticancer properties of AMR in SW620 human colon carcinoma cell line are mediated through its effects on functional genomics, targeting the apoptotic process.


Assuntos
Antineoplásicos/farmacologia , Carcinoma/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Triterpenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Carcinoma/metabolismo , Carcinoma/patologia , Linhagem Celular Tumoral , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Citocromos c/metabolismo , Citosol/enzimologia , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Mitocôndrias/enzimologia , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Heterólogo , Proteína bcl-X/efeitos dos fármacos
16.
Anticancer Res ; 25(5): 3293-302, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16101141

RESUMO

Curcumin (diferuloyl methane), the yellow-colored dietary pigment from the rhizomes of turmeric, has been recognized as a chemopreventive agent because of its antitumor, antioxidant and antiproliferative effects. The cytotoxic, apoptotic and gene regulatory effects of both turmeric and curcumin were investigated in the MCF-7 human breast cancer carcinoma cell line and compared with the effects in MCF-10A human mammary epithelial cells. MCF-7 cells were more sensitive to turmeric and curcumin than MCF-10A cells. MCF-10A cells retained comparatively less curcumin in the medium than MCF- 7 cells after 24 h, thereby reducing the cytotoxic effect. Curcumin induced a significantly higher percentage of apoptosis in MCF-7 than MCF-10A cells at all doses. Microarray hybridization of Clonetech apoptotic arrays with labeled first-strand probes of total RNA was performed to identify and characterize the genes regulated by curcumin in tumor cells. Of the 214 apoptosis-associated genes in the array, the expression of 104 genes was altered by curcumin treatment. The gene expression was altered up to 14-fold levels in MCF-7 as compared to only up to 1.5-fold in the MCF-10A cell line by curcumin. Curcumin up-regulated (>3 fold) 22 genes and down-regulated (<3-fold) 17 genes at both 25 microg/ml and 50 microg/ml doses in the MCF-7 cell line. The up-regulated genes include HIAP1, CRAF1, TRAF6, CASP1, CASP2, CASP3, CASP4, HPRT, GADD45, MCL-1, NIP1, BCL2L2, TRAP3, GSTP1, DAXX, PIG11, UBC, PIG3, PCNA, CDC10, JNK1 and RBP2. The down-regulated genes were TRAIL, TNFR, AP13, IGFBP3, SARP3, PKB, IGFBP, CASP7, CASP9, TNFSF6, TRICK2A, CAS, TRAIL-R2, RATS1, hTRIP, TNFb and TNFRSF5. While a dose-dependent gene expression change was noticed in some genes, opposite regulatory effects were induced by different curcumin doses in three apoptotic genes. These results suggest that curcumin induces apoptosis in breast cancer cells by regulation of multiple signaling pathways, indicating its potential use for prevention and treatment of cancer.


Assuntos
Antineoplásicos/farmacologia , Apoptose/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Curcumina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Curcuma , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Perfilação da Expressão Gênica , Humanos , Glândulas Mamárias Humanas/citologia , Glândulas Mamárias Humanas/efeitos dos fármacos , Glândulas Mamárias Humanas/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , Fitoterapia
17.
Int J Tuberc Lung Dis ; 9(8): 870-6, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16104633

RESUMO

BACKGROUND: Efforts to intensify global tuberculosis (TB) control are limited by difficulties in coordinating with private doctors. More than half of Indian TB patients may initially consult a private provider, but many are neither diagnosed accurately nor treated effectively. We established and evaluated a public-private partnership based on surveillance of TB detected in private laboratories and use of standardised directly observed treatment regimens. METHODS: In one district, the governmental TB control programme offered training in microscopy to all large private sector laboratories, and educated private physicians on the importance of microscopy for TB diagnosis. We reviewed records from participating private laboratories and all publicly diagnosed patients. RESULTS: Of 2328 pulmonary TB patients registered from July 2001 to December 2002, 404 (17%) were detected in the private sector. The annual new AFB-positive case notification rate increased by 21%, from 27.8/100,000 in 2000 to 33.5/100,000 in 2002. Surveillance at private laboratories found an additional 260 nonregistered AFB-positive patients. CONCLUSIONS: This public-private partnership substantially increased TB case detection and established a sustainable framework for private sector involvement in TB control. In the setting of a strong public sector programme, the combination of active surveillance of private laboratories along with physician sensitisation is a promising approach to improve TB case detection.


Assuntos
Vigilância da População , Setor Privado , Setor Público , Tuberculose Pulmonar/diagnóstico , Humanos , Índia/epidemiologia , Relações Interinstitucionais , Laboratórios/organização & administração , Laboratórios/normas , Estudos Retrospectivos
18.
Int Immunopharmacol ; 4(13): 1645-59, 2004 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-15454117

RESUMO

An alpha-D-glucan (RR1) composed of (1-->4) linked back bone and (1-->6) linked branches with a molecular mass of >550 kDa and exhibiting unique immune stimulating properties is isolated and characterized from the medicinal plant Tinospora cordifolia. This novel polysaccharide is noncytotoxic and nonproliferating to normal lymphocytes as well as tumor cell lines at 0-1000 microg/ml. It activated different subsets of the lymphocytes such as natural killer (NK) cells (331%), T cells (102%), and B cells (39%) at 100 microg/ml concentration. The significant activation of NK cells is associated with the dose-dependent killing of tumor cells by activated normal lymphocytes in a functional assay. Immune activation by RR1 in normal lymphocytes elicited the synthesis of interleukin (IL)-1beta (1080 pg/ml), IL-6 (21,833 pg/ml), IL-12 p70 (50.19 pg/ml), IL-12 p40 (918.23 pg/ml), IL-18 (27.47 pg/ml), IFN- gamma (90.16 pg/ml), tumor necrosis factor (TNF)-alpha (2225 pg/ml) and monocyte chemoattractant protein (MCP)-1 (2307 pg/ml) at 100 microg/ml concentration, while it did not induce the production of IL-2, IL-4, IL-10, interferon (IFN)-alpha and TNF-beta. The cytokine profile clearly demonstrates the Th1 pathway of T helper cell differentiation essential for cell mediated immunity, with a self-regulatory mechanism for the control of its overproduction. RR1 also activated the complements in the alternate pathway, demonstrated by a stepwise increase in C3a des Arg components. Incidentally, RR1 stimulation did not produce any oxidative stress or inducible nitric oxide synthase (iNOS) in the lymphocytes or any significant increase in nitric oxide production. The water solubility, high molecular mass, activation of lymphocytes especially NK cells, complement activation, Th1 pathway-associated cytokine profile, together with a low level of nitric oxide synthesis and absence of oxidative stress confer important immunoprotective potential to this novel alpha-D-glucan.


Assuntos
Amilopectina/imunologia , Amilopectina/isolamento & purificação , Glucanos/imunologia , Glucanos/isolamento & purificação , Imunização/métodos , Plantas Medicinais/química , Tinospora , Amilopectina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ativação do Complemento/efeitos dos fármacos , Ativação do Complemento/fisiologia , Formazans , Glucanos/farmacologia , Humanos , Índia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/metabolismo , Ayurveda , Estrutura Molecular , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Plantas Medicinais/imunologia , Tecnologia Farmacêutica/métodos , Sais de Tetrazólio
19.
In. Anon. Advancing Caribbean herbs in the 21st century. St. Augustine, The University of the West Indies, 2003. p.60-76, ilus, tab.
Monografia em Inglês | LILACS | ID: lil-386503

RESUMO

Medicinal and aromatic plants (MAPs) are horticultural crops with socio-economic significance in the Caribbean. People of the Caribbean maintain the tradition of making 'bush (herb) teas' as part of their daily activity. 'Bush tea' is made with a variety of herbs that are combined for their culinary and medicinal properties. Cultivating these plants complements conventional fruit and vegetable production in the Virgin Islands and enhance small-farm productivity. This study was initiated to evaluate the agronomic and economic potential of agroforestry systems involving MAPs with focus on alley cropping. Field experiments were conducted to determine yield and productivity of popular species of medicinal plants and aromatic herbs commonly used in the Virgin Islands. Medicinal plants included 'inflammation bush' (Verbesina alata), 'worrywine' (Stachytarpheta jamaicensis) and 'japana' (Eupatorium triplinerve) ... Data were collected on fresh and dry matter yield ... Results indicated yield of intercropped medicinal plants and herbs were not significantly reduced during the first harvest, but yield tended to decrease in subsequent harvest suggesting that tree-crop competition was minimal during the early establishment stage


Assuntos
Humanos , Região do Caribe , Comércio , Fitoterapia , Plantas Medicinais , Ilhas Virgens Americanas
20.
Indian J Pathol Microbiol ; 45(3): 319-22, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12785175

RESUMO

Blood transfusion is an important mode of transmission of infections to the recipient. The aim of the study was to assess the prevalence of transfusion transmissible infections and the possible risk factors among blood donors. During the study period (1994-99) donor samples were screened for HBsAg, HIV, HCV and Syphilis. The relevant donor history was examined to identify the risk factors leading to transfusion transmissible infections. The prevalence of infection was 3.1% among donors, with HBsAg constituting 1.3%, HCV 1.4%, HIV 0.2% and RPR 0.2%. In a classification based on occupation, class III donors (drivers, Businessmen & men in uniform) showed a significantly higher incidence of transfusion transmissible infections for HIV (0.38%) and Syphilis (0.36%). Health care workers constituted only a small fraction of the study; prevalence of infections was low among them. History of jaundice or hospitalization was not associated with higher incidence of seropositivity. Seropositivity for HIV is relatively low compared to similar studies conducted in other regions of the country. This finding is attributed to the pre donation counseling in donor selection. An important outcome of the study is that Class III donors form a high-risk group for transfusion transmissible infections.


Assuntos
Armazenamento de Sangue/métodos , Doadores de Sangue , Hepatite Viral Humana/epidemiologia , Fatores de Risco , Inquéritos e Questionários , Reação Transfusional , Adulto , Transmissão de Doença Infecciosa , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Hepatite Viral Humana/transmissão , Humanos , Índia , Masculino
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