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2.
Sci Total Environ ; 568: 1263-1274, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27267722

RESUMO

Ecosystem monitoring networks aim to collect data on physical, chemical and biological systems and their interactions that shape the biosphere. Here we introduce the Australian SuperSite Network that, along with complementary facilities of Australia's Terrestrial Ecosystem Research Network (TERN), delivers field infrastructure and diverse, ecosystem-related datasets for use by researchers, educators and policy makers. The SuperSite Network uses infrastructure replicated across research sites in different biomes, to allow comparisons across ecosystems and improve scalability of findings to regional, continental and global scales. This conforms with the approaches of other ecosystem monitoring networks such as Critical Zone Observatories, the U.S. National Ecological Observatory Network; Analysis and Experimentation on Ecosystems, Europe; Chinese Ecosystem Research Network; International Long Term Ecological Research network and the United States Long Term Ecological Research Network. The Australian SuperSite Network currently involves 10 SuperSites across a diverse range of biomes, including tropical rainforest, grassland and savanna; wet and dry sclerophyll forest and woodland; and semi-arid grassland, woodland and savanna. The focus of the SuperSite Network is on using vegetation, faunal and biophysical monitoring to develop a process-based understanding of ecosystem function and change in Australian biomes; and to link this with data streams provided by the series of flux towers across the network. The Australian SuperSite Network is also intended to support a range of auxiliary researchers who contribute to the growing body of knowledge within and across the SuperSite Network, public outreach and education to promote environmental awareness and the role of ecosystem monitoring in the management of Australian environments.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Austrália , Geografia
3.
Gigascience ; 5: 21, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27195106

RESUMO

BACKGROUND: Microbial inhabitants of soils are important to ecosystem and planetary functions, yet there are large gaps in our knowledge of their diversity and ecology. The 'Biomes of Australian Soil Environments' (BASE) project has generated a database of microbial diversity with associated metadata across extensive environmental gradients at continental scale. As the characterisation of microbes rapidly expands, the BASE database provides an evolving platform for interrogating and integrating microbial diversity and function. FINDINGS: BASE currently provides amplicon sequences and associated contextual data for over 900 sites encompassing all Australian states and territories, a wide variety of bioregions, vegetation and land-use types. Amplicons target bacteria, archaea and general and fungal-specific eukaryotes. The growing database will soon include metagenomics data. Data are provided in both raw sequence (FASTQ) and analysed OTU table formats and are accessed via the project's data portal, which provides a user-friendly search tool to quickly identify samples of interest. Processed data can be visually interrogated and intersected with other Australian diversity and environmental data using tools developed by the 'Atlas of Living Australia'. CONCLUSIONS: Developed within an open data framework, the BASE project is the first Australian soil microbial diversity database. The database will grow and link to other global efforts to explore microbial, plant, animal, and marine biodiversity. Its design and open access nature ensures that BASE will evolve as a valuable tool for documenting an often overlooked component of biodiversity and the many microbe-driven processes that are essential to sustain soil function and ecosystem services.


Assuntos
Bases de Dados Factuais , Análise de Sequência de DNA/métodos , Microbiologia do Solo , Archaea/classificação , Archaea/genética , Austrália , Bactérias/classificação , Bactérias/genética , Biodiversidade , Fungos/classificação , Fungos/genética , Metagenômica , Filogenia
4.
Eur Heart J ; 29(5): 665-72, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18263873

RESUMO

AIMS: Diabetes increases the risk of atherothrombosis, but reduces the risk of abdominal aortic aneurysm (AAA). The reason for this difference is unknown. We examined the role of diabetes and glycation on AAA expansion and extracellular matrix-monocyte interactions. METHODS AND RESULTS: We followed 198 patients (20 with diabetes) who had 30-45 mm AAAs with yearly aortic ultrasound for 3 years. Diabetes was independently associated with reduced AAA growth (beta = -0.17, P = 0.01; OR for expansion above median 0.18, 95% confidence interval 0.06-0.57). In vitro incubation of resting human monocytes with glycated bovine serum albumin or monomeric type I collagen increased matrix metalloproteinase (MMP) secretion. In contrast, exposure of activated monocytes to glycated type I collagen lattices induced a marked reduction in MMP and interleukin-6 secretion. This de-activating effect was also demonstrated in cross-linked non-glycated collagen lattices, healthy decellularized aortic media, and decellularized aortic media from diabetes patients with atherosclerosis. In contrast, decellularized aortic media from patients with atherosclerosis, but no diabetes, induced increased MMP secretion. CONCLUSION: These findings confirm that the progression of AAA is slower in patients with diabetes and suggest a mechanism by which the aortic media may be protected from degradation in these individuals.


Assuntos
Aneurisma da Aorta Abdominal/patologia , Aterosclerose/complicações , Citocinas/fisiologia , Angiopatias Diabéticas/patologia , Monócitos/fisiologia , Idoso , Aneurisma da Aorta Abdominal/enzimologia , Angiopatias Diabéticas/enzimologia , Métodos Epidemiológicos , Matriz Extracelular/enzimologia , Feminino , Humanos , Masculino , Metaloproteinases da Matriz/metabolismo
5.
Curr Genomics ; 9(1): 29-42, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19424482

RESUMO

A family history of atherosclerosis is independently associated with an increased incidence of cardiovascular events. The genetic factors underlying the importance of inheritance in atherosclerosis are starting to be understood. Genetic variation, such as mutations or common polymorphisms has been shown to be involved in modulation of a range of risk factors, such as plasma lipoprotein levels, inflammation and vascular calcification. This review presents examples of present studies of the role of genetic polymorphism in atherosclerosis.

6.
Plant Cell Physiol ; 48(11): 1589-600, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17925311

RESUMO

Flower color is mainly determined by anthocyanins. Rosa hybrida lacks violet to blue flower varieties due to the absence of delphinidin-based anthocyanins, usually the major constituents of violet and blue flowers, because roses do not possess flavonoid 3',5'-hydoxylase (F3'5'H), a key enzyme for delphinidin biosynthesis. Other factors such as the presence of co-pigments and the vacuolar pH also affect flower color. We analyzed the flavonoid composition of hundreds of rose cultivars and measured the pH of their petal juice in order to select hosts of genetic transformation that would be suitable for the exclusive accumulation of delphinidin and the resulting color change toward blue. Expression of the viola F3'5'H gene in some of the selected cultivars resulted in the accumulation of a high percentage of delphinidin (up to 95%) and a novel bluish flower color. For more exclusive and dominant accumulation of delphinidin irrespective of the hosts, we down-regulated the endogenous dihydroflavonol 4-reductase (DFR) gene and overexpressed the Irisxhollandica DFR gene in addition to the viola F3'5'H gene in a rose cultivar. The resultant roses exclusively accumulated delphinidin in the petals, and the flowers had blue hues not achieved by hybridization breeding. Moreover, the ability for exclusive accumulation of delphinidin was inherited by the next generations.


Assuntos
Antocianinas/metabolismo , Flavonoides/biossíntese , Flores/metabolismo , Rosa/metabolismo , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Antocianinas/química , Flavonoides/química , Flores/genética , Concentração de Íons de Hidrogênio , Estrutura Molecular , Fenótipo , Pigmentos Biológicos/química , Pigmentos Biológicos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Rosa/genética
8.
Circulation ; 111(23): 3119-25, 2005 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-15939823

RESUMO

BACKGROUND: Abdominal aortic aneurysm (AAA) is characterized by destruction of the arterial media associated with loss of vascular smooth muscle cells, infiltration of mononuclear cells, and high concentration of metalloproteinases (MMPs) and cytokines. Osteoprotegerin (OPG) has recently been identified in atherosclerosis. The presence and functional importance of OPG in human AAA was investigated. METHODS AND RESULTS: In 146 men with small AAA followed up by ultrasound for 3 years, serum OPG was weakly correlated with aneurysm growth rate. Western analysis showed 3-, 8-, and 12-fold-greater OPG concentrations in human AAA biopsies compared with biopsies of atherosclerotic narrowed aorta (1.4+/-0.1 versus 0.5+/-0.1 ng/mg tissue; P=0.002), postmortem nondiseased abdominal aorta (1.4+/-0.1 versus 0.2+/-0.1 ng/mg tissue; P<0.001), and nondiseased thoracic aorta (1.4+/-0.1 versus 0.1+/-0.06 ng/mg tissue; P<0.001). Healthy human aortic vascular smooth muscle cells incubated with recombinant human (rh)OPG (0 to 20 ng rhOPG/10(5) cells per 1 mL per 24 hours) developed an aneurysmal phenotype defined by impaired cell proliferation (P<0.001), increased apoptosis (P<0.01), and increased MMP-9 (92 kDa) expression (P<0.001). Incubation of monocytic THP-1 cells with 1 ng rhOPG/10(5) cells per 1 mL per 24 hours induced a 2-fold increase in MMP-9 expression (P<0.001), a 1.5-fold increase in MMP-2 activity (P=0.005), and a 2-fold stimulation of IL-6 production in these cells (P=0.02). Finally, secretion of OPG from human AAA explant was abrogated by treatment with the angiotensin II blocker irbesartan, with the reduction in secreted levels averaging 63.0+/-0.9 ng/mg tissue per 48-hour period. CONCLUSIONS: These findings support a role for OPG in the growth of human AAA and suggest a potential benefit for angiotensin II blockade in slowing aneurysm expansion.


Assuntos
Aneurisma da Aorta Abdominal/etiologia , Glicoproteínas/farmacologia , Adulto , Idoso , Angiotensina II/antagonistas & inibidores , Aorta Abdominal/citologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/patologia , Apoptose , Biópsia , Compostos de Bifenilo/farmacologia , Proliferação de Células , Células Cultivadas , Progressão da Doença , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Irbesartana , Masculino , Metaloproteinase 9 da Matriz/genética , Pessoa de Meia-Idade , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Osteoprotegerina , Receptores Citoplasmáticos e Nucleares , Receptores do Fator de Necrose Tumoral , Proteínas Recombinantes/farmacologia , Tetrazóis/farmacologia , Ultrassonografia
9.
Stroke ; 35(7): 1636-41, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15143295

RESUMO

BACKGROUND AND PURPOSE: The aim of this study was to compare the concentration of osteoprotegerin (OPG), receptor activator of nuclear factor kappaB ligand (RANKL), and osteopontin (OPN) in stable (asymptomatic) and unstable (symptomatic) carotid atherosclerosis. In addition, we were interested in the effect of angiotensin II blockade on the secretion of these proteins by unstable atherosclerosis. METHODS: Endarterectomy samples removed from patients with recent (within 6 weeks) or no previous focal neurological symptoms were assessed by immunohistochemistry, Western analysis, and explant culture. Concentrations of OPG, RANKL, and OPN were measured by mean optical density (MOD), densitometry of protein bands, and enzyme-linked immunosorbent assay of supernatants from explant culture, and compared between symptomatic and asymptomatic patients. RESULTS: The concentration of OPG and OPN within the proximal internal carotid (PIC) part of the endarterectomy specimen removed from symptomatic patients was elevated 2- and 4-fold, respectively. Although the concentration of RANKL did not differ according to patients' symptoms, the quantity of OPG secreted by explants of the PIC was greater in explants from symptomatic patients and could be significantly reduced within 48 hours of incubation with the angiotensin II blocker irbesartan. CONCLUSIONS: OPG and OPN are upregulated in symptomatic human carotid atherosclerosis with possible implications for plaque stability. Angiotensin II blockade is able to downregulate OPG secretion in vitro.


Assuntos
Arteriosclerose/metabolismo , Estenose das Carótidas/metabolismo , Glicoproteínas/biossíntese , Receptores Citoplasmáticos e Nucleares/biossíntese , Sialoglicoproteínas/biossíntese , Idoso , Angiotensina II/antagonistas & inibidores , Arteriosclerose/tratamento farmacológico , Arteriosclerose/patologia , Compostos de Bifenilo/uso terapêutico , Western Blotting , Estenose das Carótidas/tratamento farmacológico , Estenose das Carótidas/patologia , Proteínas de Transporte/biossíntese , Proteínas de Transporte/metabolismo , Técnicas de Cultura , Feminino , Glicoproteínas/metabolismo , Humanos , Imuno-Histoquímica , Irbesartana , Masculino , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Osteopontina , Osteoprotegerina , Ligante RANK , Receptor Ativador de Fator Nuclear kappa-B , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores do Fator de Necrose Tumoral , Sialoglicoproteínas/metabolismo , Tetrazóis/uso terapêutico , Regulação para Cima
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