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1.
Conserv Physiol ; 12(1): coad105, 2024.
Article in English | MEDLINE | ID: mdl-38293637

ABSTRACT

Fishing causes direct removal of individuals from wild populations but can also cause a physiological disturbance in fish that are released or discarded after capture. While sublethal physiological effects of fish capture have been well studied in commercial and recreational fisheries, this issue has been overlooked for the ornamental fish trade, where it is common to capture fish from the wild and discard non-target species. We examined metabolic responses to capture and discard procedures in the three-striped dwarf cichlid Apistogramma trifasciata, a popular Amazonian aquarium species that nonetheless may be discarded when not a target species. Individuals (n = 34) were tagged and exposed to each of four treatments designed to simulate procedures during the capture and discard process: 1) a non-handling control; 2) netting; 3) netting +30 seconds of air exposure; and 4) netting +60 seconds of air exposure. Metabolic rates were estimated using intermittent-flow respirometry, immediately following each treatment then throughout recovery overnight. Increasing amounts of netting and air exposure caused an acute increase in oxygen uptake and decrease in available aerobic scope. In general, recovery occurred quickly, with rapid decreases in oxygen uptake within the first 30 minutes post-handling. Notably, however, male fish exposed to netting +60 seconds of air exposure showed a delayed response whereby available aerobic scope was constrained <75% of maximum until ~4-6 hours post-stress. Larger fish showed a greater initial increase in oxygen uptake post-stress and slower rates of recovery. The results suggest that in the period following discard, this species may experience a reduced aerobic capacity for additional behavioural/physiological responses including feeding, territory defence and predator avoidance. These results are among the first to examine impacts of discard practises in the ornamental fishery and suggest ecophysiological research can provide valuable insight towards increasing sustainable practises in this global trade.

2.
Photodiagnosis Photodyn Ther ; 38: 102788, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35235837

ABSTRACT

BACKGROUND: A plant extract (EB) incorporated into glass ionomer cement (GIG) could be a potential photosensitizer for Antimicrobial PDT (aPDT) against caries-microorganisms, replacing methylene blue (MB), due to the presence of chlorophyll. GIC + EB + aPDT could be an therapeutic alternative to dentin decontamination and sealing, allowing reduction of operative time. OBJECTIVE: Evaluate Dioscorea altissima (EB) incorporated into GIC as a photosensitizer for aPDT against Streptococcus mutans. METHODS: Groups (n = 24; ntotal = 192): G1-GIC; G2-GIC + LASER; G3-GIC/EB; G4-GIC/EB + LASER; G5-GIC+MB; G6-GIC + aPDT; G7-GIC/EB + MB; and G8 - GIC/EB+aPDT. In aPDT groups, MB was the photosensitizer. In LASER groups, MB was not used. The irradiation protocol was 660 nm/100 mW/5 J/150 J/cm²/50 s, with a 5-min pre-irradiation time for the MB groups. Antibacterial assays were carried out in 24-well microplates. The wells were completed with one milliliter of a S. mutans in BHI at 1.3 × 108 CFU/mL suspension. After incubation, PDT or laser was performed. After MTT bacteria viability test, the data were submitted to the Kolgomorov-Smirnoff normality test, followed by one-way ANOVA and Tukey's posterior test, α < 0.05. RESULTS: Group G6 showed significant inhibition (p < 0.001), followed by groups G4, G5, G7, and G8, which did not show significant differences among them (p > 0.05). Groups G2 and G3 also showed similar results (p > 0.05) and were the least active compared to the others. CONCLUSIONS: EB potentiated the antimicrobial action of GIC against S. mutans and laser irradiation over GIC/EB presented better antimicrobials results. The results indicate that EB could be a potential photosensitizer for aPDT.


Subject(s)
Anti-Infective Agents , Photochemotherapy , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/therapeutic use , Biofilms , Glass Ionomer Cements , Methylene Blue/pharmacology , Photochemotherapy/methods , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Plant Extracts/pharmacology , Streptococcus mutans
3.
Emerg Infect Dis ; 26(5): 993-997, 2020 05.
Article in English | MEDLINE | ID: mdl-32310064

ABSTRACT

We investigated a Q fever outbreak that occurred in an isolated area of the Amazon Rain Forest in French Guiana in 2014. Capybara fecal samples were positive for Coxiella burnetii DNA. Being near brush cutters in use was associated with disease development. Capybaras are a putative reservoir for C. burnetii.


Subject(s)
Coxiella burnetii , Q Fever , Animals , Coxiella burnetii/genetics , Disease Outbreaks , French Guiana/epidemiology , Q Fever/epidemiology , Rainforest , Rodentia
4.
Chem Biodivers ; 16(10): e1900374, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31441194

ABSTRACT

The essential oils (EOs) obtained from the leaves of Iryanthera polyneura Ducke trees was chemically Assessed and tested for the ability of inhibiting the growth of Candida albicans, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus mutans and S. sanguinis. The oil was also tested against breast (MCF-7) and prostate (PC-3) cancer cell lines. Minimum bactericidal concentrations (MBCs) and 50 % inhibition concentrations (IC50 ) values were obtained. EOs were active against Gram-positive bacteria. Spathulenol, α-cadinol and τ-muurolol were major components of EOs. The oils showed a higher cytotoxicity against PC-3 than MCF-7 cells, although the oils were active against both cell types. Oils obtained from leaves collected in the dry season were more active against E. faecalis, S. aureus and PC-3, while the oils obtained from leaves collected in the rainy season were more active against S. mutans, S. sanguinis and MCF-7. The antibacterial and cytotoxic activities of the essential oils from the leaves of I. polyneura are related to the seasonal climate variation and are influenced by compounds that are minor components of the oils.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Myristicaceae/chemistry , Oils, Volatile/pharmacology , Plant Leaves/chemistry , Seasons , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Antineoplastic Agents, Phytogenic/chemical synthesis , Antineoplastic Agents, Phytogenic/chemistry , Brazil , Cell Proliferation/drug effects , Drug Screening Assays, Antitumor , Humans , MCF-7 Cells , Microbial Sensitivity Tests , Oils, Volatile/chemical synthesis , Oils, Volatile/chemistry , PC-3 Cells , Rainforest
5.
Am Nat ; 190(5): 631-648, 2017 11.
Article in English | MEDLINE | ID: mdl-29053360

ABSTRACT

The ecological traits of organisms may predict their genetic diversity and population genetic structure and mediate the action of evolutionary processes important for speciation and adaptation. Making these ecological-evolutionary links is difficult because it requires comparable genetic estimates from many species with differing ecologies. In Amazonian birds, habitat association is an important component of ecological diversity. Here, we examine the link between habitat association and genetic parameters using 20 pairs of closely related Amazonian bird species in which one member of the pair occurs primarily in forest edge and floodplains and the other occurs in upland forest interior. We use standardized geographic sampling and data from 2,416 genomic markers to estimate genetic diversity, population genetic structure, and statistics reflecting demographic and evolutionary processes. We find that species of upland forest have greater genetic diversity and divergence across the landscape as well as signatures of older histories and less gene flow than floodplain species. Our results reveal that species ecology in the form of habitat association is an important predictor of genetic diversity and population divergence and suggest that differences in diversity between floodplain and upland avifaunas in the Amazon may be driven by differences in the demographic and evolutionary processes at work in the two habitats.


Subject(s)
Biological Evolution , Birds/genetics , Ecosystem , Genetic Variation , Animals , Forests , Genetic Speciation , South America
6.
J Ethnopharmacol ; 173: 383-423, 2015 Sep 15.
Article in English | MEDLINE | ID: mdl-26234177

ABSTRACT

ETHNOPHARMACOLOGICAL IMPORTANCE: The use of medicinal plants for treatment, cure and prevention of diseases has been described by many people since time immemorial. Because of this use, commercial and scientific interests have emerged, making it necessary to realize ethnobotanical surveys of medicinal plants species, which is important for subsequent chemical and pharmacological bioprospections. AIM OF THE STUDY: This study aimed at surveying, identifying, cataloging and documenting the medicinal plants species used in the Valley of Juruena, Northwestern Mato Grosso, Legal Amazon Brazil for the treatment of various human diseases, as well as assessed the species of interest for bioprospecting potential. MATERIALS AND METHODS: Informants were interviewed using semi-structured form to capture information on socio-demographic and ethnopharmacological data of medicinal plants such as vernacular name, uses, geographic origin, habit, form of preparation and part used. Results were analyzed using descriptive and quantitative means: indices of use-report (Ur) and informant consensus factor (ICF), for the selection of plant species with therapeutic potential. RESULTS: Three hundred and thirty two (332) plants species belonging to 90 families were reported for medicinal purposes and totaling 3973 use-reports were reported by 365 (92.9%) of the people interviewed. Asteraceae (32.2%), Fabaceae (26.7%) and Lamiaceae (24.4%) families were the most represented, with majority being species native (64.45%) to Brazil. Leaves (64.5%) were the part of the plant most used and infusion (45.7%) was the most utilized form. Gastrointestinal disorders followed by respiratory complaints topped the list of use-reports. The native or naturalized plants with the highest use reports in the order of decreasing absolute frequency per each emic-category are Cymbopogon citratus (DC.) Stapfc (104), Mentha pulegium L. (94), Arrabidaea chica (Humb. & Bonpl.) B. Verl. (97), Alternanthera brasiliana (L.) Kuntze (71), Baccharis crispa Spreng (57), Phyllanthus niruri L. (48), Gossypium barbadense L. (44), Solidago microglossa DC. (40) and Bauhinia forficata L. (20). And the most cited exotics are: Chenopodium ambrosioides L. (151), Aloe vera (L.) Burm. f., (89) and Rosmarinus officinalis L. (72). In some cases, high ICF values were found, which reflects high degree of homogeneity of consensus among informants in this region on medicinal plants. CONCLUSION: The population of Valle of Juruena makes use of a wide array of medicinal plants distributed in all use categories with predominance of those use in the treatments of gastrointestinal and respiratory ailments. The therapeutic potential of some of the species of medicinal importance extensively utilized by the population of the region have been scientifically validated, and are therefore promising prototype of new drugs. However, there are some of these species whose ethnomedicinal uses are yet to be scientifically verified and thus constitute an unexplored terrain for future biological/pharmacological studies.


Subject(s)
Phytotherapy , Plants, Medicinal , Adult , Brazil , Ethnobotany , Female , Health Knowledge, Attitudes, Practice , Humans , Male , Medicine, Traditional , Middle Aged , Surveys and Questionnaires
7.
Braz J Microbiol ; 45(3): 769-79, 2014.
Article in English | MEDLINE | ID: mdl-25477906

ABSTRACT

Previous studies analyzing 2,200 plant extracts indicated anti-enterococcal activity in 25 extracts obtained from Brazilian forests' plants. In the present study, these extracts were subjected to microdilution broth assay (MDBA) and disk diffusion assay (DDA) using planktonic Enterococcus faecalis ATCC(®) 29212™ and were submitted to phytochemical analysis in TLC and HPLC. Three extracts obtained from Ipomoea alba (MIC < 40 µg/mL), Diclinanona calycina (MIC ≤ 40 µg/mL) and Moronobea coccinea (40 < MIC < 80 µg/mL; MBC = 80 µg/mL) showed significant bactericidal activity in the MDBA and four extracts obtained from I. alba (14.04 ± 0.55 mm diameter) S. globulifera (14.43 ± 0.33 mm and 12.18 ± 0.28 mm diameter) and Connarus ruber var. ruber (13.13 ± 0.18 mm diameter) were active in DDA. Residues H2O obtained from Psidium densicomum (mean of 16.78 mm diameter) and from Stryphnodendron pulcherrimum (mean of 15.97 mm diameter) have shown an improved antibacterial activity after fractionation if compared to that obtained from the respective crude extracts. Antioxidant activity was observed in some residues of the active extracts. TLC analysis showed that phenolic compounds are likely to be found in active extracts. Three molecules were isolated from S. globulifera and were identified by (13)C NMR lupeol, α-amyrin and 3ß-hydroxyglutin-5-ene. The present chemical and biological findings suggest that these extracts are a potential source of new anti-Enterococcus compounds to be introduced in endodontic therapy.


Subject(s)
Anti-Bacterial Agents/pharmacology , Enterococcus faecalis/drug effects , Plant Extracts/pharmacology , Plants/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Brazil , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Models, Molecular , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/isolation & purification
8.
Braz. j. microbiol ; 45(3): 769-779, July-Sept. 2014. ilus, graf, tab
Article in English | LILACS | ID: lil-727001

ABSTRACT

Previous studies analyzing 2,200 plant extracts indicated anti-enterococcal activity in 25 extracts obtained from Brazilian forests' plants. In the present study, these extracts were subjected to microdilution broth assay (MDBA) and disk diffusion assay (DDA) using planktonic Enterococcus faecalis ATCC® 29212TM and were submitted to phytochemical analysis in TLC and HPLC. Three extracts obtained from Ipomoea alba (MIC < 40 µg/mL), Diclinanona calycina (MIC < 40 µg/mL) and Moronobea coccinea (40 < MIC < 80 µg/mL; MBC = 80 µg/mL) showed significant bactericidal activity in the MDBA and four extracts obtained from I. alba (14.04 ± 0.55 mm diameter) S. globulifera (14.43 ± 0.33 mm and 12.18 ± 0.28 mm diameter) and Connarus ruber var. ruber (13.13 ± 0.18 mm diameter) were active in DDA. Residues H2O obtained from Psidium densicomum (mean of 16.78 mm diameter) and from Stryphnodendron pulcherrimum (mean of 15.97 mm diameter) have shown an improved antibacterial activity after fractionation if compared to that obtained from the respective crude extracts. Antioxidant activity was observed in some residues of the active extracts. TLC analysis showed that phenolic compounds are likely to be found in active extracts. Three molecules were isolated from S. globulifera and were identified by 13C NMR lupeol, α-amyrin and 3β-hydroxyglutin-5-ene. The present chemical and biological findings suggest that these extracts are a potential source of new anti-Enterococcus compounds to be introduced in endodontic therapy.


Subject(s)
Anti-Bacterial Agents/pharmacology , Enterococcus faecalis/drug effects , Plant Extracts/pharmacology , Plants/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Brazil , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Models, Molecular , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/isolation & purification
9.
Arq. bras. med. vet. zootec ; 66(2): 374-380, Jan.-Apr. 2014. graf
Article in Portuguese | LILACS | ID: lil-709273

ABSTRACT

No mundo todo, as verminoses são causa de considerável prejuízo econômico na criação de ovinos. As perdas estão relacionadas ao retardo na produção, custos com tratamentos profiláticos e, em casos extremos, à morte dos animais. O objetivo deste trabalho foi verificar a ação anti-helmíntica de extratos vegetais sobre nematoides como alternativa terapêutica no tratamento da verminose em ovinos. Extratos orgânicos e aquosos foram obtidos de plantas nativas da Floresta Amazônica e Mata Atlântica, e foram testados na concentração de 100µg/mL em ensaios de toxicidade in vitro contra ovos de Haemonchus contortus e de 200µg/mL contra suas larvas. Na concentração estabelecida, apresentaram significante atividade relacionada à inibição de eclosão de ovos; em particular, o extrato orgânico de folhas e frutos de Trichilia sp. e o extrato aquoso dos órgãos aéreos de Phyllanthus attenuatus. Os resultados in vitro sugerem que extratos aquosos e orgânicos dessas plantas podem oferecer novas alternativas de controle da verminose em ovinos a partir de produtos naturais...


Helminthosis play a crucial role in small ruminant production leading to enormous economic losses particularly in areas where extensive grazing is practiced. It causes a loss of production through mortality, weight loss, reduced milk and wool production. Haemonchus contortus is a highly pathogenic small ruminant helminthes parasite, which is capable of causing acute diseases and high mortality. Therefore, there is an urgent need to seek alternative or complementary solutions to the control of parasitic nematodes of ruminants. The tropical forests concentrate the highest biodiversity in the world, particularly those located in Brazil, whose species richness is estimated to account for 20% of the total world richness and little is known about the chemical and pharmacological potentialities of Brazilian tropical forests. In this work, organic and aqueous extracts were tested on eggs and in the larval development test on Haemonchus contortus. The organic extract obtained from leaves and fruits of Trichilia sp. and the aqueous extract obtained from the aerial organs of Phyllanthus attenuates showed significant activity related to the inhibition of H. contortus egg eclosion. In vitro results suggest that both extracts, as well as eleven other active extracts, can offer alternatives in sheep worm control...


Subject(s)
Anthelmintics/therapeutic use , Plant Extracts/administration & dosage , Haemonchus , Phytotherapy
10.
Rev. bras. farmacogn ; 23(6): 903-912, Nov-Dec/2013. tab, graf
Article in English | LILACS | ID: lil-704262

ABSTRACT

The organic extract EB689, obtained from the stem of Abarema auriculata (Benth.) Barneby & J.W.Grimes, Fabaceae, commonly known as "saboeiro-ferro", was chemically studied, as well as its influence over behavioral effects such as locomotion, emotionality and anxiety, after intra-peritonial administration were assessed. The open-field and elevated-plus maze were used in experiments divided into two stages. The first stage aimed for the identification of the main effects over behavior using a reduced number of animals against half-fold diluted doses of EB689. The same variables were also tested in a second stage of the experiment using the non-lethal intra-peritoneal dose of 4.8 mg/kg in a larger number of animals. It was observed that EB689 clearly decreased locomotion, which was probably caused by internal hemorrhage causing hypovolemic shock. Although it is the first time lupeol and eucryphin are described in A. auriculata, it is still not clear if they are involved in the toxicology of A. auriculata. The undesirable effects of EB689 are better understood, the basis for further pharmacological assays aiming antitumor activity are supported.

11.
Biota neotrop. (Online, Ed. port.) ; 10(1): 321-324, Apr. 2010. graf, tab
Article in English | LILACS | ID: lil-556918

ABSTRACT

The Coleoptera fauna of forensic importance associated with Sus scrofa Linnaeus, 1758 carcass decomposition in Ducke Reserve, Manaus, Brazil, was determined. A total of 41 species, belonging to six families and 11 subfamilies were collected. Staphylinidae presented the higher richness with 17 species sampled, followed by Histeridae, with 11 and Scarabaeidae with nine species. Euspilotus azureus (Sahlberg, 1823) (Histeridae), Aleochara sp. (Staphylinidae) and Oxelytrum cayennense (Stürm, 1826) (Silphidae) occurred in all stages of decomposition. Omalodes lucidus Erichson, 1824 and Scapomegas auritus Marseul, 1855 (Histeridae) are recorded for the first time in the Amazon, being also reported for the first time associated with a decomposing carcass. The fauna differs from those of other Brazilian regions, emphasizing the importance of studies to determine the regional insect fauna of forensic importance that can be used in criminal investigations.


A fauna de Coleoptera de importância forense foi analisada na Reserva Ducke, Manaus, Brasil, durante a decomposição de carcaça de Sus scrofa Linnaeus, 1758. Foram coletadas 41 espécies, pertencentes a seis famílias e 11 subfamílias. Staphylinidae apresentou a maior riqueza com 17 espécies, seguida por Histeridae, com 11 e Scarabaeidae com nove espécies. Euspilotus azureus (Sahlberg, 1823) (Histeridae), Aleochara sp. (Staphylinidae) e Oxelytrum cayennense (Stürm, 1826) (Silphidae) ocorreram em todos os estágios de decomposição. Omalodes lucidus Erichson, 1824 e Scapomegas auritus Marseul, 1855 (Histeridae) são registrados pela primeira vez na Amazônia, sendo também a primeira amostragem na qual essas espécies são encontradas em carcaça em decomposição. A fauna difere das de outras regiões do Brasil, ressaltando a importância de estudos regionais para posterior utilização como provas forenses.

12.
J. Health Sci. Inst ; 25(2)abr.-jun. 2007. tab
Article in Portuguese | LILACS | ID: lil-661268

ABSTRACT

Introdução - Em trabalho prévio, 705 extratos vegetais oriundos de plantas amazônicas e da Mata Atlântica foram triados no teste antibacteriano da microdiluição em caldo. No presente trabalho, os extratos ativos foram identificados e submetidos à avaliação da concentração mínima inibitória e da concentração bactericida mínima usando o mesmo modelo experimental. Material e Métodos - Foi utilizado o ensaio da microdiluição em caldo, que consiste em se avaliar a susceptibilidade das bactérias aos extratos vegetais em meio ágar caldo, em microplacas de 96 poços. Resultados = Os extratos orgânicos obtidos de Rapanea parvifolia (MY841), Smilax rufescens (SM53) e Ruizterania retusa (VO581) mostraram atividade antibacteriana. MY841 e SM53 mostraram atividade contra Enterococcus faecalis CIM = 30 ?g/ml; CBM = 60 ?g/ml e CIM = 80 ?g/ml; CBM = 90 ?g/ml, respectivamente) e VO581 mostrou atividade contra Staphylococcusaureus (CIM = 140 ?g/ml; CBM = 160 ?g/ml) e leve atividade contra Pseudomonas aeruginosa (CIM = 200 ?g/ml; CBM = 380 ?g/ml). Conclusões - Estes três extratos apresentaram atividade importante contra as bactérias testadas, devendo, portanto, ser fracionados e os compostos majoritários avaliados.


Introduction - Up to 705 plant extracts from Amazon Rain Forest and Atlantic Rain Forest were screened against bacteria using the microdilution broth assay. In the present work, minimal inhibitory concentration and minimal bactericidal concentration were obtained from the three selected active extracts. Material and Methods - The microdilution broth assay used in the present analysis consists in evaluating small amounts of extract against the bacteria in agar broth medium in 96 well microplates. Results - Three organic extracts obtained from Rapanea parvifolia (MY841), Smilax rufescens (SM53) and Ruizterania retusa (VO581) showed antibacterial activity. MY841 and SM53 showed activity against Enterococcus faecalis MIC = 30 mg/ml; MBC = 60 mg/ml and MIC = 80 mg/ml; MBC = 90 mg/ml, respectively) and VO581 showed activity against Staphylococcus aureus (MIC = 140 mg/ml; MBC = 160 mg/ml) and a mild activity against Pseudomonas aeruginosa (MIC = 200 mg/ml; MBC = 380 mg/ml). Conclusions - The three extracts showed important activity against the bacteria, and they are going to be fractionated and the fractions evaluated against the antibacterial model. The major compounds are going to be isolated as well.


Subject(s)
Humans , Pharmacology , Plants, Medicinal , Plant Extracts , Microbial Sensitivity Tests , Anti-Bacterial Agents , Bacteria , Enterococcus faecalis , Herbal
13.
Clinics ; 62(6): 763-768, 2007.
Article in English | LILACS | ID: lil-471797

ABSTRACT

Plants have played a significant role in the treatment of cancer and infectious diseases for the last four decades. The discovery and introduction to market of paclitaxel, the vinca alkaloids, etoposide, and many antibacterial drugs support drug discovery programs based on natural products. Natural products have been rediscovered as important tools for drug development despite advances in combinatorial chemistry, due to the complex molecular structures able to interact with mammalian cell targets. The Brazilian flora, the most diverse in the world, has become an interesting spot to prospect for new chemical leads or hits due to its species diversity and associated chemical richness. Screening programs have been established in Brazil as a strategy to identify potentially active substances. High throughput screening techniques allow for the analysis of large numbers of extracts in a relatively short period of time, and can be considered one of the most efficient ways of finding new leads from natural products. An updated review of the current status of the biological screening program is presented and recent results from new antitumoral and antibacterial chemical leads are discussed.


Plantas são uma importante fonte de novos protótipos há pelo menos quatro décadas. A descoberta e introdução no mercado de paclitaxel, dos alcalóides da vinca, etoposídeo e muitos agentes antibacterianos têm servido de apoio ao desenvolvimento de programas de descobrimento de novos fármacos baseados em produtos naturais. Produtos naturais foram recentemente redescobertos como importante ferramenta na descoberta de novos fármacos devido às estruturas moleculares complexas capazes de interagir com alvos em células de mamíferos. A flora brasileira, a mais rica do mundo, tornou-se um importante sítio para prospecção de novos protótipos em decorrência da riqueza de espécies vegetais relacionada a uma possível diversidade química. Programas de triagem têm sido introduzidos no Brasil contrapondo a devastação de florestas relacionadas a atividades rurais, extrativismo madeireiro e mineral. Ensaios em larga escala permitem a análise de um grande número de amostras em um tempo relativamente pequeno, e pode ser considerado como o método mais eficaz para a descoberta de novos fármacos a partir de plantas. Dados atualizados relativos a programas de triagem que objetivam a identificação de novos protótipos antitumorais e antibacterianos são comentados.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antineoplastic Agents/pharmacology , Drug Discovery , Plant Extracts/chemistry , Plants, Medicinal/chemistry , Technology, Pharmaceutical , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Biodiversity , Brazil , Drug Design , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Trees
14.
Oecologia ; 122(3): 410-420, 2000 Feb.
Article in English | MEDLINE | ID: mdl-28308292

ABSTRACT

We examined standard niche axes (time, place, and food) for three sympatric teiid lizards in the Amazon rain forest. Activity times during the day were similar among species. Ameiva ameiva were in more open microhabitats and had higher body temperatures compared with the two species of Kentropyx. Microhabitat overlaps were low and not significantly different from simulations based on Monte Carlo analysis. Grasshoppers, crickets, and spiders were important in the diets of all three species and many relatively abundant prey were infrequently eaten (e.g., ants). Dietary overlaps were most similar between the two species of Kentropyx even though microhabitat overlaps were relatively low. A Monte Carlo analysis on prey types revealed that dietary overlaps were higher at all ranks than simulated overlaps indicating that use of prey is not random. Although prey size was correlated with lizard body size, there were no species differences in adjusted prey size. A. ameiva ate more prey items at a given body size than either species of Kentropyx. Body size varies among species, with A. ameiva being the largest and K. altamazonica the smallest. The two species of Kentropyx are most distant morphologically, with A. ameiva intermediate. The most distant species morphologically are the most similar in terms of prey types. A morphological analysis including 15 species from four genera revealed patterns of covariation that reflected phylogenetic affinities (i.e., taxonomic patterns are evident). A cluster analysis revealed that A. ameiva, K. pelviceps, and K. altamazonica were in the same morphological group and that within that group, A. ameiva differed from the rest of the species. In addition, K. pelviceps and K. altamazonica were distinguishable from other species of Kentropyx based on morphology.

15.
Acta amaz ; 28(3)1998.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454655

ABSTRACT

The leaf-feeding species Syntermes molestus and S. spinosus are two dominant termite species in Reserva Ducke in Central Amazonia; two other species (S. aculeosus, S. longiceps) exist in the area. All species except S. aculeosus were also found in urban areas. The workers of S. molestus and S. spinosus have average body dry weights of 4.5±0.2 and 13.1±1.4 mg, and the weight of their soldiers is 8.2±0.2 and 51.0±1.7 mg, respectively. Therefore, S. spinosus is among the largest termites of the world. In both species, fresh weight is about 4.7 higher than dry weight (a wider relation than in other termite species). The biomass of the populations of both species amounted to about 1 g m-2 (dry weight; indirect estimate), which rises previous assessments of the total termite biomass by about 36-45%, to a value of 3.0-3.5 g m-2.


As espécies comedoras de folhas Syntermes molestus and S. spinosus são duas espécies de cupins dominantes na Reserva Ducke na Amazônia Central; duas outras espécies (S. aculeosus, S. longiceps) existem na área. Todas as espécies (exceto S. aculeosus) são encontradas também em áreas urbanas. O peso seco médio do corpo dos operários de S. molestus e S. spinosus é de 4,5±0,2 e 13,1±1,4 mg, e dos soldados é de 8,2±0,2 and 51,0±1,7 mg, respectivamente. Por isto, S. spinosus está entre os maiores cupins do mundo. Em ambas espécies, o peso fresco é cerca de 4,7 vezes mais alto que o peso seco (uma proporção maior que em outras espécies de cupins). A biomassa das populações de ambas espécies foi avaliada em cerca de 1 g m-2 (peso seco; estimativa indireta), o que eleva estimativas anteriores da biomassa total de térmitas em cerca de 36-45%, a um valor de 3,0-3,5 g m-2.

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