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1.
Braz. j. biol ; 79(2): 263-272, Apr.-June 2019. tab, graf
Article in English | LILACS | ID: biblio-989458

ABSTRACT

Abstract The distribution of most species occurs in delimited regions with unique characteristics called "centers of endemism". In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70's. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees' responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.


Resumo A distribuição da maioria das espécies ocorre em regiões delimitadas com características únicas conhecidas como "centros de endemismo". Na Amazônia Oriental está localizado o Centro de Endemismo Belém (CEB), uma das áreas mais intensivamente desmatadas na Amazônia Brasileira. Aqui, apresentamos informações sobre assembleias de abelhas orquídeas baseadas em registros históricos de coleções entomológicas. Para cada espécie, foram calculadas a frequência de ocorrência e a dominância, classificando-as em 3 estados: espécies comuns, intermediárias ou raras. Foram geradas curvas de riqueza observada e estimada, com base no estimador Jackknife. Encontramos 1.257 espécimes de 56 espécies, constituindo registros de 1917 a 2009, e uma espécie é um novo registro no CEB. Maior número de espécimes e espécies foi concentrado em poucos locais, com intensificação nas coletas a partir dos anos70. Os resultados sugerem alta riqueza de abelhas orquídeas no CEB, embora esse cenário esteja longe do que é esperado para toda a área. A elevada ocorrência de espécies raras pode estar relacionada à baixa representatividade nas coleções e a proximidade entre as áreas favoreceu as amostragens. Mesmo assim, a lista de espécies e o estado de conservação aqui apresentados podem ser informações úteis em estudos interessados em comparar a fauna passada e atual de abelhas das orquídeas e, aliado a dados sobre as respostas das abelhas às mudanças de uso da terra ocorridas no CEB ao longo dos anos, podem servir de base para definição de áreas prioritárias para conservação.


Subject(s)
Animals , History, 20th Century , History, 21st Century , Bees/classification , Bees/physiology , Brazil , Endangered Species , Conservation of Natural Resources
2.
Braz J Biol ; 79(2): 263-272, 2019.
Article in English | MEDLINE | ID: mdl-30110081

ABSTRACT

The distribution of most species occurs in delimited regions with unique characteristics called "centers of endemism". In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70's. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees' responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.


Subject(s)
Bees , Animals , Bees/classification , Bees/physiology , Brazil , Conservation of Natural Resources , Endangered Species , History, 20th Century , History, 21st Century
3.
Phys Chem Chem Phys ; 21(3): 1260-1270, 2019 Jan 17.
Article in English | MEDLINE | ID: mdl-30566130

ABSTRACT

Abasic sites (AP site) in a DNA duplex have been experimentally used to produce fluorescent Ag nanoclusters (NC) with a small number of atoms (n ≤ 6). These AP-DNA:NC complexes act as biological makers that help to locate genes associated with diseases related to single nucleotide polymorphisms (SNP), for example. Abasic sites are the most common SNP genetic variation, and their detection may help predict a host of genetically determined diseases. In this work, we report a theoretical study of the optical absorption spectra of AP-DNA:Ag4 and AP-DNA:Au4 complexes using a fully ab initio methodology. We consider several different base environments for the noble-metal nanocluster occupying the AP site, and compute the absorption spectra of sixteen AP-DNA:Ag4 and sixteen AP-DNA:Au4 complexes. We find that optical absorption in the AP-DNA:Ag4 complexes tends to concentrate in the green-to-violet range of frequencies (2.50 eV ≤ hω ≤ 3.2 eV) and that AP-DNA:Au4 complexes display absorption peaks in the violet-to-ultraviolet interval (hω ≥ 3.0 eV). An analysis of the optical absorption mechanisms in these complexes shows that they can be of local, charge-transfer, or hybrid nature, i.e., AP-DNA:NC complexes display the full variety of optical absorption processes in molecular systems. In particular, we identify both charge-transfer and hybrid processes involving several DNA bases surrounding the NC. Importantly, we find that even sequences where the Ag4 cluster is not in a guanine rich neighborhood display absorption peaks in the visible-light spectrum. Moreover, we obtain that the maximum intensities of the absorption peaks in complexes with pyrimidine vacancies are generally higher than those in complexes with purine vacancies. Regarding the selectivity of single-vacancy AP-DNA to specific noble-metal nanocluster sizes, our calculations show that the four-atom Ag4 (Au4) species fits naturally and binds into the AP-site in a single-vacancy AP-DNA.


Subject(s)
DNA/chemistry , Gold/chemistry , Metal Nanoparticles/chemistry , Silver/chemistry , DNA/radiation effects , Density Functional Theory , Light , Metal Nanoparticles/radiation effects , Models, Chemical , Molecular Structure , Spectrum Analysis
4.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467190

ABSTRACT

Abstract The distribution of most species occurs in delimited regions with unique characteristics called centers of endemism. In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70s. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.


Resumo A distribuição da maioria das espécies ocorre em regiões delimitadas com características únicas conhecidas como centros de endemismo. Na Amazônia Oriental está localizado o Centro de Endemismo Belém (CEB), uma das áreas mais intensivamente desmatadas na Amazônia Brasileira. Aqui, apresentamos informações sobre assembleias de abelhas orquídeas baseadas em registros históricos de coleções entomológicas. Para cada espécie, foram calculadas a frequência de ocorrência e a dominância, classificando-as em 3 estados: espécies comuns, intermediárias ou raras. Foram geradas curvas de riqueza observada e estimada, com base no estimador Jackknife. Encontramos 1.257 espécimes de 56 espécies, constituindo registros de 1917 a 2009, e uma espécie é um novo registro no CEB. Maior número de espécimes e espécies foi concentrado em poucos locais, com intensificação nas coletas a partir dos anos70. Os resultados sugerem alta riqueza de abelhas orquídeas no CEB, embora esse cenário esteja longe do que é esperado para toda a área. A elevada ocorrência de espécies raras pode estar relacionada à baixa representatividade nas coleções e a proximidade entre as áreas favoreceu as amostragens. Mesmo assim, a lista de espécies e o estado de conservação aqui apresentados podem ser informações úteis em estudos interessados em comparar a fauna passada e atual de abelhas das orquídeas e, aliado a dados sobre as respostas das abelhas às mudanças de uso da terra ocorridas no CEB ao longo dos anos, podem servir de base para definição de áreas prioritárias para conservação.

5.
Surg Radiol Anat ; 35(6): 535-8, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23262557

ABSTRACT

This article describes the clinical case of an 86-year-old female patient with an asymptomatic clinical condition, without presenting a history of previous traumatisms. When routine radiographic exam-panoramic radiograph-was performed, the following extensions of the paranasal sinuses were found: maxillary sinus (palate), sphenoid sinus (pterygoid process, major wing, and anterior clinoid process), and supraorbital portion of the frontal sinus. Thus computerized tomography was performed to confirm the diagnosis.


Subject(s)
Frontal Sinus/diagnostic imaging , Maxillary Sinus/diagnostic imaging , Radiography, Panoramic , Sphenoid Sinus/diagnostic imaging , Aged, 80 and over , Denture, Complete , Female , Frontal Sinus/anatomy & histology , Humans , Incidental Findings , Maxillary Sinus/abnormalities , Paranasal Sinuses/anatomy & histology , Paranasal Sinuses/diagnostic imaging , Risk Assessment , Sphenoid Sinus/anatomy & histology , Tomography, X-Ray Computed/methods
6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(3 Pt 2B): 036407, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11909262

ABSTRACT

A local dispersion relation that describes inhomogeneity-driven instabilities in the lower-hybrid range is derived following a procedure that correctly describes energy exchange between waves and particles in inhomogeneous media, correcting some inherent ambiguities associated with the standard formalism found in the literature. Numerical solutions of this improved dispersion relation show that it constitutes a unified formulation for the instabilities in the lower-hybrid range, describing the so-called modified two-stream instability, excited by the ion cross-field drift, including the ion Weibel instability, and also describing the lower-hybrid drift instability, which is due to inhomogeneity effects on the electron population.

7.
Arq Neuropsiquiatr ; 57(3B): 898-902, 1999 Sep.
Article in Portuguese | MEDLINE | ID: mdl-10751934

ABSTRACT

Professor Antonio Austregésilo was the pioneer of neurology in Brazil, creating the first neurologícal school, in Rio de Janeiro, of which he was the first professor. He was also the first to study the movement disorders in Brazil, publishing several works on this subject, primarily in "Revue Neurologique", and "L'Encephale", including a rival sign of Babinski and the first description of a posttraumatic dystonia.


Subject(s)
Dyskinesias/history , Neurology/history , Brazil , History, 20th Century , Humans
8.
Mycoses ; 40(9-10): 343-4, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9470418

ABSTRACT

Paracoccidioidomycosis has been rarely reported among HIV patients, despite being an endemic mycosis in Latin America. The present report illustrates a case of PM in a teenager infected with HIV. Clinicians must be aware that this mycosis may occur in young HIV infected patients who live in endemic areas.


Subject(s)
AIDS-Related Opportunistic Infections/etiology , HIV Infections/complications , Paracoccidioidomycosis/etiology , Adolescent , Humans , Male , Paracoccidioides/isolation & purification , Substance Abuse, Intravenous/complications
9.
J Appl Toxicol ; 14(1): 21-6, 1994.
Article in English | MEDLINE | ID: mdl-8157865

ABSTRACT

Tordon herbicide, which is a mixture of 4-amino-3,5,6-trichloropicolinic acid (picloram) and 2,4-dichlorophenoxyacetic acid (2,4-D), depresses the phosphorylation efficiency of the rat liver mitochondria, as inferred from the decrease of the respiratory control coefficient and the ADP/O ratios when NAD(+)-dependent substrates were used; NADH oxidase and NADH cytochrome c reductase were also inhibited, without any effect on the other enzymatic complexes of the respiratory chain. Tordon (66.2 nmol picloram + 270 nmol 2,4-D mg-1 protein) affected the amplitude of swelling induced by glutamate, succinate, (N,N,N',N'-tetramethyl-p-phenyldiamine + sodium ascorbate and ATP. These results characterize an interaction of Tordon with complex I of the respiratory chain and also a partial collapse of the proton motive force of the mitochondrial inner membrane without affecting its elasticity.


Subject(s)
2,4-Dichlorophenoxyacetic Acid/toxicity , Energy Metabolism/drug effects , Herbicides/toxicity , Mitochondria, Liver/metabolism , Picloram/toxicity , Animals , Cell Membrane/drug effects , Cell Membrane/enzymology , Cell Membrane/metabolism , In Vitro Techniques , Mitochondria, Liver/drug effects , Mitochondria, Liver/enzymology , Mitochondrial Swelling/drug effects , Oxidation-Reduction , Oxygen Consumption/drug effects , Phosphorylation/drug effects , Protein Biosynthesis , Rats
10.
Arq Neuropsiquiatr ; 49(3): 330-2, 1991 Sep.
Article in Portuguese | MEDLINE | ID: mdl-1807235

ABSTRACT

A case of a 14 year-old boy suffering from Kleine-Levin syndrome is described. The diagnosis was made by symptoms which suggested this disorder: megaphagia, hypersomnia and hypersexuality. A brief review is made emphasizing the pathophysiology, diagnosis and treatment of this syndrome which is frequently misdiagnosed.


Subject(s)
Disorders of Excessive Somnolence , Hyperphagia , Personality Disorders , Adolescent , Humans , Male , Syndrome
11.
Res Commun Chem Pathol Pharmacol ; 55(1): 59-65, 1987 Jan.
Article in English | MEDLINE | ID: mdl-3563106

ABSTRACT

The effect of antiarrhythmic drugs (propranolol, lidoflazine, perhexiline maleate and iproveratril) on Ca2+ uptake and Na+-induced Ca2+ release by isolated rat heart mitochondria has been studied using arsenazo III as Ca2+ indicator. It was concluded that those drugs are not selective inhibitors either for Na+-induced Ca2+ release or for Ca2+ uptake. It seems possible that those drugs act by complexation with some components of the membrane, presumably with phospholipids.


Subject(s)
Anti-Arrhythmia Agents/pharmacology , Calcium/metabolism , Mitochondria, Heart/metabolism , Animals , Biological Transport, Active/drug effects , Kinetics , Mitochondria, Heart/drug effects , Rats , Sodium/pharmacology
12.
Cell Biochem Funct ; 4(4): 289-96, 1986 Oct.
Article in English | MEDLINE | ID: mdl-2878737

ABSTRACT

Effects of the antiarrhythmic drugs (propranolol, perhexiline maleate, lidoflazine and iproveratril) on energy-linked reactions and on membrane potential were studied. Propranolol, perhexiline maleate and lidoflazine inhibit the ATPase activity of undamaged and broken mitochondria, and of submitochondrial particles. All drugs are inhibitors of either ATP-driven or of succinate-driven reduction of NADP+. The antiarrhythmics promote a decrease in the membrane potential upon energization of the mitochondrial membrane by alpha-ketoglutarate, succinate, or ATP. It was suggested that these drugs have a primary action on the mitochondrial membrane, thus altering the activities of membrane proteins (channels and enzymes).


Subject(s)
Adenosine Triphosphatases/metabolism , Anti-Arrhythmia Agents/pharmacology , Intracellular Membranes/physiology , Mitochondria, Heart/physiology , Submitochondrial Particles/physiology , Animals , Intracellular Membranes/drug effects , Kinetics , Membrane Potentials/drug effects , Mitochondria, Heart/drug effects , Proton-Translocating ATPases/metabolism , Rats , Submitochondrial Particles/drug effects
18.
Res Commun Chem Pathol Pharmacol ; 10(1): 149-54, 1975 Jan.
Article in English | MEDLINE | ID: mdl-235776

ABSTRACT

The effects of iproveratril on oxygen uptake and oxidative phosphorylation of succinate, glutamate and alfa-ketoglutarate were studied. Oxidative phosphorylation and oxidation of NAD+-linked substrated by heart mitochondria were depressed by 1.15 times 10-3M iproveratril. The activity of NADH-oxidase, NADH-cytochrome c reductase and heart mitochondrial transporting particles were depressed by iproveratril. When succinate was the substrate oxidative phosphorylation was depressed but oxygen uptake was stimulated about 370%. Swelling induced by iproveratril was analysed by electron microscopy.


Subject(s)
Mitochondria/metabolism , Myocardium/ultrastructure , Verapamil/pharmacology , Animals , Cytochrome Reductases/antagonists & inhibitors , Cytochrome c Group , Glutamates/metabolism , In Vitro Techniques , Ketoglutaric Acids/metabolism , Male , Microscopy, Electron , Mitochondria/drug effects , Mitochondria/enzymology , NAD , NADH, NADPH Oxidoreductases/antagonists & inhibitors , Oxidative Phosphorylation/drug effects , Oxygen Consumption/drug effects , Polarography , Rats , Succinates/metabolism
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