National Institute for Amazon Research

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National Institute for Amazon Research

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de Carvalho A.L.,National Institute for Amazon Research | d'Oliveira M.V.N.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária | Putz F.E.,University of Florida | de Oliveira L.C.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária
Forest Ecology and Management | Year: 2017

We evaluated the impacts of selective logging on tree regeneration one, four, and eight years after harvests in Antimary State Forest in the State of Acre, Brazil. We inventoried tree seedlings, saplings, and poles (>50 cm tall to <10 cm DBH) on secondary roads, log landing, and skid trails, as well as in the bole and crown zones of canopy gaps created by felling; for comparison we also sampled areas not affected directly by logging. We compared these habitats on the basis soil (physical) characteristics, canopy cover, and floristic composition. For areas one and four years after logging, we supplemented the ground-based information with aerial LiDAR data. By eight years post-logging the size class distributions of tree regeneration in all habitat types resembled those in unlogged areas, and densities were only lower in crown gaps. Eight years after logging, relative densities of pioneer trees were highest on secondary roads and log landings; no among habitat differences were observed in the relative densities of non-pioneer species at any time along the chronosequence. Tree species diversity (Fisher's alpha) converged on unlogged values on skid trails, bole gaps, and crown gaps at 8-years post-logging, but values remained lower on secondary roads and log landings. Canopy openness was greatest one year after logging, especially in log landings (mean 45.4 ± SE 4.5%) whereas four and eight years post-logging it did not exceed 10% and no differences were found among habitats. Soil bulk density was elevated relative to un-logged areas only on log landings one and four years after logging, and this difference disappeared by eight years post-logging. The total area disturbed by logging varied from 7.0% to 8.6% with nearly half of the totals in felling gaps (3.0–3.7%). © 2017 Elsevier B.V.


Pinto A.C.D.S.,Federal University of Amazonas | Chaves F.C.M.,Embrapa Amazonia Ocidental | Dos Santos P.A.,National Institute for Amazon Research | Nunez C.V.,National Institute for Amazon Research | And 2 more authors.
Planta Medica | Year: 2010

Piper peltatum L. is used for the treatment of inflammation, malaria, and other ailments. 4-Nerolidylcatechol (4-NC) is a valuable natural product that has important anti-inflammatory, antimalarial, and antioxidant properties. 4-NC is a component of P. peltatum and P. umbellatum extracts, which are used in cosmetics. The aim of this work was to evaluate the production of plant biomass and the production of 4-NC in roots of cultivated P. peltatum over a full life cycle. Seedlings were produced in a greenhouse and then transplanted. The weight of dry plant parts (leaves, stems, roots, and inflorescences); numbers of stems, leaves, and inflorescences; and the leaf-to-stem ratio were evaluated at intervals of 60 days after transplanting (DAT). Extracts were prepared using 1:1 ethanolchloroform and an ultrasound bath. Roots, leaves, and inflorescences contained 4-NC according to TLC photodensitometry analysis. Quantification of 4-NC in root extracts was performed using HPLCDAD analysis. Per-hectare production of 4-NC by roots was estimated based on quantitative HPLC analysis and biomass data. Optimal per-hectare yields of 4-NC were obtained by harvesting roots between 350 and 400 DAT. In this period, the average yield was 27kg 4-NC per hectare. Importantly, at the time of maximal overall production of root biomass (470 DAT), there was a decrease in the production of 4-NC (23.8kg/ha), probably due to the onset of senescence. © 2010 Georg Thieme Verlag KG Stuttgart · New York.


Albuquerque A.C.F.,Federal University of Amazonas | Dos Santos J.L.C.,National Institute for Amazon Research | De Castro A.N.,Federal University of Amazonas
Proceedings of the Annual Hawaii International Conference on System Sciences | Year: 2015

The use of ontology presents a novel data integration resource, when centred in semantic definitions and the need for interoperability. Results from previews works indicate that ontologies can drive knowledge acquisition processes for the purpose of comprehensive, transportable machine understanding and knowledge management. Applied to the biodiversity domain, ontologies can be a valuable resource for strategic planning and its contribution toward conservation of the Amazon region. This work presents a biodiversity domain ontology developed at the National Institute for Amazonian Research (INPA) using biological data as its object of study. © 2015 IEEE.


PubMed | Federal University of Minas Gerais, Federal University of Amazonas, National Institute for Amazon Research, EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária and 2 more.
Type: Journal Article | Journal: Antimicrobial agents and chemotherapy | Year: 2015

4-Nerolidylcatechol (1) is an abundant antiplasmodial metabolite that is isolated from Piper peltatum roots. O-Acylation or O-alkylation of compound 1 provides derivatives exhibiting improved stability and significant in vitro antiplasmodial activity. The aim of this work was to study the in vitro inhibition of hemozoin formation, inhibition of isoprenoid biosynthesis in Plasmodium falciparum cultures, and in vivo antimalarial activity of several 4-nerolidylcatechol derivatives. 1,2-O,O-Diacetyl-4-nerolidylcatechol (2) inhibited in vitro hemozoin formation by up to 50%. In metabolic labeling studies using [1-(n)-(3)H]geranylgeranyl pyrophosphate, diester 2: significantly inhibited the biosynthesis of isoprenoid metabolites ubiquinone 8, menaquinone 4, and dolichol 12 in cultures of P. falciparum 3D7. Similarly, 2-O-benzyl-4-nerolidylcatechol (3) significantly inhibited the biosynthesis of dolichol 12. P. falciparum in vitro protein synthesis was not affected by compounds 2 or 3. At oral doses of 50 mg per kg of body weight per day, compound 2 suppressed Plasmodium berghei NK65 in infected BALB/c mice by 44%. This in vivo result for derivative 2 represents marked improvement over that obtained previously for natural product 1. Compound 2 was not detected in mouse blood 1 h after oral ingestion or in mixtures with mouse blood/blood plasma in vitro. However, it was detected after in vitro contact with human blood or blood plasma. Derivatives of 4-nerolidylcatechol exhibit parasite-specific modes of action, such as inhibition of isoprenoid biosynthesis and inhibition of hemozoin formation, and they therefore merit further investigation for their antimalarial potential.


Pohlit A.M.,National Institute for Amazon Research | Pohlit A.M.,University of Sao Paulo | Lopes N.P.,University of Sao Paulo | Gama R.A.,Federal University of Rio Grande do Norte | And 2 more authors.
Planta Medica | Year: 2011

Bites of mosquitoes belonging to the genera Anopheles Meigen, Aedes Meigen, Culex L. and Haemagogus L. are a general nuisance and are responsible for the transmission of important tropical diseases such as malaria, hemorrhagic dengue and yellow fevers and filariasis (elephantiasis). Plants are traditional sources of mosquito repelling essential oils (EOs), glyceridic oils and repellent and synergistic chemicals. A Chemical Abstracts search on mosquito repellent inventions containing plant-derived EOs revealed 144 active patents mostly from Asia. Chinese, Japanese and Korean language patents and those of India (in English) accounted for roughly 3/4 of all patents. Since 1998 patents on EO-containing mosquito repellent inventions have almost doubled about every 4 years. In general, these patents describe repellent compositions for use in topical agents, cosmetic products, incense, fumigants, indoor and outdoor sprays, fibers, textiles among other applications. 67 EOs and 9 glyceridic oils were individually cited in at least 2 patents. Over 1/2 of all patents named just one EO. Citronella [Cymbopogon nardus (L.) Rendle, C.winterianus Jowitt ex Bor] and eucalyptus (Eucalyptus L'Hér. spp.) EOs were each cited in approximately 1/3 of all patents. Camphor [Cinnamomum camphora (L.) J. Presl], cinnamon (Cinnamomum zeylanicum Blume), clove [Syzygium aromaticum (L.) Merr. & L. M. Perry], geranium (Pelargonium graveolens L'Hér.), lavender (Lavandula angustifolia Mill.), lemon [Citrus × limon (L.) Osbeck], lemongrass [Cymbopogon citratus (DC.) Stapf] and peppermint (Mentha × piperita L.) EOs were each cited in > 10 % of patents. Repellent chemicals present in EO compositions or added as pure natural ingredients such as geraniol, limonene, p-menthane-3,8-diol, nepetalactone and vanillin were described in approximately 40 % of all patents. About 25 % of EO-containing inventions included or were made to be used with synthetic insect control agents having mosquito repellent properties such as pyrethroids, N,N-diethyl-m- toluamide (DEET), (±)-p-menthane-3,8-diol (PMD) and dialkyl phthalates. Synergistic effects involving one or more EOs and synthetic and/or natural components were claimed in about 10 % of all patents. Scientific literature sources provide evidence for the mosquito repellency of many of the EOs and individual chemical components found in EOs used in patented repellent inventions. © Georg Thieme Verlag KG Stuttgart New York.


Guimaraes J.P.,University of Sao Paulo | Mari R.D.B.,Paranaense University | Marigo J.,State University of Rio de Janeiro | Rosas F.C.W.,National Institute for Amazon Research | Watanabe I.-S.,University of Sao Paulo
Zoological Science | Year: 2011

The importance of the tongue during feeding, and the limited information on the tongue of most aquatic mammals led us to investigate its morphological aspects in sexually immature and mature Sotalia guianensis. Six tongues were measured and photo-documented after their removal from the oral cavity. The samples were divided into rostral, middle, and caudal regions, and examined using light microscopy and scanning electron microscopy (S.E.M.). Sotalia guianensis tongue presented lateral grooves from the apex to the middle portion, while the anterolateral region presented marginal papillae. Histological characteristics revealed the presence of a keratinized stratified epithelium, salivary glands in the middle and caudal portions of the tongue, and filiform papillae in the caudal region. S.E.M. images revealed the presence of filiform papillae and ducts of salivary glands in the middle and caudal portions of the tongue. We can conclude that the characteristics found in this study may reflect an adaptation to changes in diet after weaning. © 2011 Zoological Society of Japan.


de Carvalho A.L.,National Institute for Amazon Research | Nelson B.W.,National Institute for Amazon Research | Bianchini M.C.,Institute Criminalistica do Amazonas IC | Plagnol D.,National Institute for Amazon Research | And 2 more authors.
PLoS ONE | Year: 2013

We map the extent, infer the life-cycle length and describe spatial and temporal patterns of flowering of sarmentose bamboos (Guadua spp) in upland forests of the southwest Amazon. We first examine the spectra and the spectral separation of forests with different bamboo life stages. False-color composites from orbital sensors going back to 1975 are capable of distinguishing life stages. These woody bamboos flower produce massive quantities of seeds and then die. Life stage is synchronized, forming a single cohort within each population. Bamboo dominates at least 161,500 km2 of forest, coincident with an area of recent or ongoing tectonic uplift, rapid mechanical erosion and poorly drained soils rich in exchangeable cations. Each bamboo population is confined to a single spatially continuous patch or to a core patch with small outliers. Using spatial congruence between pairs of mature-stage maps from different years, we estimate an average life cycle of 27-28 y. It is now possible to predict exactly where and approximately when new bamboo mortality events will occur. We also map 74 bamboo populations that flowered between 2001 and 2008 over the entire domain of bamboo-dominated forest. Population size averaged 330 km2. Flowering events of these populations are temporally and/or spatially separated, restricting or preventing gene exchange. Nonetheless, adjacent populations flower closer in time than expected by chance, forming flowering waves. This may be a consequence of allochronic divergence from fewer ancestral populations and suggests a long history of widespread bamboo in the southwest Amazon. © 2013 Carvalho et al.


Baptista R.B.,National Institute for Amazon Research | Souza-Castro N.,National Institute for Amazon Research | Almeida-Val V.M.F.,National Institute for Amazon Research
Fish Physiology and Biochemistry | Year: 2016

Amazon fish maintain oxygen uptake through a variety of strategies considered evolutionary and adaptive responses to the low water oxygen saturation, commonly found in Amazon waters. Oscar (Astronotus ocellatus) is among the most hypoxia-tolerant fish in Amazon, considering its intriguing anaerobic capacity and ability to depress oxidative metabolism. Previous studies in hypoxia-tolerant and non-tolerant fish have shown that hypoxia-inducible factor-1α (HIF-1α) gene expression is positively regulated during low oxygen exposure, affecting vascular endothelial growth factor (VEGF) transcription and fish development or tolerance in different manners. However, whether similar isoforms exists in tolerant Amazon fish and whether they are affected similarly to others physiological responses to improve hypoxia tolerance remain unknown. Here we evaluate the hepatic HIF-1α and VEGF mRNA levels after 3 h of acute hypoxia exposure (0.5 mgO2/l) and 3 h of post-hypoxia recovery. Additionally, hematological parameters and oxidative enzyme activities of citrate synthase (CS) and malate dehydrogenase (MDH) were analyzed in muscle and liver tissues. Overall, three sets of responses were detected: (1) as expected, hematocrit, hemoglobin concentration, red blood cells, and blood glucose increased, improving oxygen carrying capacity and glycolysis potential; (2) oxidative enzymes from liver decreased, corroborating the tendency to a widespread metabolic suppression; and (3) HIF-1α and VEGF increased mRNA levels in liver, revealing their role in the oxygen homeostasis through, respectively, activation of target genes and vascularization. This is the first study to investigate a hypoxia-related transcription factor in a representative Amazon hypoxia-tolerant fish and suggests that HIF-1α and VEGF mRNA regulation have an important role in enhancing hypoxia tolerance in extreme tolerant species. © 2016 Springer Science+Business Media Dordrecht


Lima A.J.N.,National Institute for Amazon Research | Suwa R.,Japan Forestry and Forest Products Research Institute | De Mello Ribeiro G.H.P.,National Institute for Amazon Research | Kajimoto T.,Japan Forestry and Forest Products Research Institute | And 7 more authors.
Forest Ecology and Management | Year: 2012

Precise estimation of biomass at a regional scale is required for evaluating forest carbon stocks throughout the Amazon. We examined six types of allometric models to identify the best estimator of biomass in primary forests (terra firme) in the northwestern sector of the Brazilian Amazon. We also tested six regression models for estimating tree height. We developed each allometric model using measurements of 101 trees excavated in a primary forest distributed along the upper Rio Negro. A simple power function with stem diameter at breast height D as a single variable was selected as the best model for estimating each biomass component, i.e. above-ground total mass AGW, below-ground total mass BGW, and whole individual mass. Among models developed to estimate tree height H from D, we selected a regression model with a coefficient corresponding to an asymptotic height as the best fit. The D-AGW relationship at our study site differed significantly from models developed previously for other regions of the Amazon. We explain this regional variation in part by regional differences in D-H relationships of sample trees. The D-BGW relationship at our site also differed significantly from that in the central Amazon. However, AGW-BGW relationships were consistent between the upper Rio Negro forest and other forests in the central Amazon, in that the BGW-AGW ratio was constant as 0.136 regardless of tree size. On the basis of D-based allometry and census data from 23 plots established in the upper Rio Negro region, we estimated a stand-level total biomass (dry mass) of 252.6Mgha -1. This estimate is at least 73% lower than the potential stand biomass for the region previously suggested by several meta-analyses. © 2012 Elsevier B.V.


PubMed | National Institute for Amazon Research
Type: Journal Article | Journal: Fish physiology and biochemistry | Year: 2016

Amazon fish maintain oxygen uptake through a variety of strategies considered evolutionary and adaptive responses to the low water oxygen saturation, commonly found in Amazon waters. Oscar (Astronotus ocellatus) is among the most hypoxia-tolerant fish in Amazon, considering its intriguing anaerobic capacity and ability to depress oxidative metabolism. Previous studies in hypoxia-tolerant and non-tolerant fish have shown that hypoxia-inducible factor-1 (HIF-1) gene expression is positively regulated during low oxygen exposure, affecting vascular endothelial growth factor (VEGF) transcription and fish development or tolerance in different manners. However, whether similar isoforms exists in tolerant Amazon fish and whether they are affected similarly to others physiological responses to improve hypoxia tolerance remain unknown. Here we evaluate the hepatic HIF-1 and VEGF mRNA levels after 3h of acute hypoxia exposure (0.5mgO2/l) and 3h of post-hypoxia recovery. Additionally, hematological parameters and oxidative enzyme activities of citrate synthase (CS) and malate dehydrogenase (MDH) were analyzed in muscle and liver tissues. Overall, three sets of responses were detected: (1) as expected, hematocrit, hemoglobin concentration, red blood cells, and blood glucose increased, improving oxygen carrying capacity and glycolysis potential; (2) oxidative enzymes from liver decreased, corroborating the tendency to a widespread metabolic suppression; and (3) HIF-1 and VEGF increased mRNA levels in liver, revealing their role in the oxygen homeostasis through, respectively, activation of target genes and vascularization. This is the first study to investigate a hypoxia-related transcription factor in a representative Amazon hypoxia-tolerant fish and suggests that HIF-1 and VEGF mRNA regulation have an important role in enhancing hypoxia tolerance in extreme tolerant species.

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