Insights into structure and function of CdcVEGFs, the vascular endothelial growth factor from Crotalus durissus collilineatus snake venom.

Vascular endothelial growth factors (VEGFs) are crucial molecules involved in the modulation of angiogenesis. Snake venom-derived VEGFs (svVEGFs) are known to contribute significantly to the envenoming due to their capacity of increasing vascular permeability. In our work, we isolated and analyzed the biochemical and functional properties of the VEGF from Crotalus durissus collilineatus venom (CdcVEGF). The venom was fractionated by reversed phase chromatography on FPLC system (Fast Protein Liquid Chromatography) and the eluted fractions were submitted to an ELISA assay using an anti-VEGF-F antibody, for identification of svVEGF. Positive fractions for svVEGF were submitted to SDS-PAGE and to an anion exchange chromatography to isolate the molecule. The subfractions were analyzed by ELISA and SDS-PAGE and six of them presented svVEGFs, named CdcVEGF1 (Q23-3), CdcVEGF2 (Q24-3), CdcVEGF3 (Q24-4), CdcVEGF4 (Q25-3), CdcVEGF5 (Q25-4), and CdcVEGF6 (Q25-5). Their structural characterization was accomplished by mass spectrometry analysis using MALDI-TOF to determine their molecular masses and UPLC-ESI-QTOF to determine their amino acid sequence. Interestingly, all isolated CdcVEGFs induced angiogenesis on HUVEC cells through tube formation on Matrigel when compared to culture medium (negative control). Moreover, CdcVEGF2 and CdcVEGF3 also induced a significant increase in tube formation when compared to the positive control (basic fibroblast growth factor - bFGF). Additionally, crotalid antivenom produced by the Instituto Butantan was able to recognize CdcVEGFs, demonstrating to be immunogenic. This study demonstrates that snake venom cocktail can reveal novel and important molecules, which are potential molecular tools to study diverse biological processes, such as angiogenesis.

Antitumoral effects of γCdcPLI, a PLA2 inhibitor from Crotalus durissus collilineatus via PI3K/Akt pathway on MDA-MB-231 breast cancer cell.

Phospholipases A2 (PLA2s) overexpression is closely associated with the malignant potential of breast cancers. Here, we showed for the first the antitumoral effects of γCdcPLI, a PLA2 inhibitor from Crotalus durissus collilineatus via PI3K/Akt pathway on MDA-MB-231 cell. Firstly, γCdcPLI was more cytotoxic to MDA-MB-231 breast cancer cells than other cell lines (MCF-7, HeLa, PC3 and A549) and did not affect the viability of non-tumorigenic breast cell (MCF 10A). In addition, γCdcPLI induced modulation of important mediators of apoptosis pathways such as p53, MAPK-ERK, BIRC5 and MDM2. γCdcPLI decreased MDA-MB-231 adhesion, migration and invasion. Interestingly, the γCdcPLI also inhibited the adhesion and migration of endothelial cells and blocked angiogenesis by inhibiting tube formation by HUVECs in vitro and sprouting elongation on aortic ring assay ex vivo. Furthermore, γCdcPLI reduced the production of vascular endothelial growth factor (VEGF). γCdcPLI was also able to decrease PGE2 levels in MDA-MB-231 and inhibited gene and protein expression of the PI3K/Akt pathway. In conclusion, γCdcPLI showed in vitro antitumoral, antimestatatic and anti-angiogenic potential effects and could be an attractive approach for futures studies in cancer therapy.

Antitumoral effects of gamma CdcPLI, a PLA(2) inhibitor from Crotalus durissus collilineatus via PI3K/Akt pathway on MDA-MB-231 breast cancer cell

Phospholipases A(2) (PLA(2)s) overexpression is closely associated with the malignant potential of breast cancers. Here, we showed for the first the antitumoral effects of gamma CdcPLI, a PLA2 inhibitor from Crotalus durissus collilineatus via PI3K/Akt pathway on MDA-MB-231 cell. Firstly, gamma CdcPLI was more cytotoxic to MDA-MB-231 breast cancer cells than other cell lines ( MCF-7, HeLa, PC3 and A549) and did not affect the viability of non-tumorigenic breast cell (MCF 10A). In addition, gamma CdcPLI induced modulation of important mediators of apoptosis pathways such as p53, MAPK-ERK, BIRC5 and MDM2.gamma CdcPLI decreased MDA-MB-231 adhesion, migration and invasion. Interestingly, the gamma CdcPLI also inhibited the adhesion and migration of endothelial cells and blocked angiogenesis by inhibiting tube formation by HUVECs in vitro and sprouting elongation on aortic ring assay ex vivo. Furthermore,gamma CdcPLI reduced the production of vascular endothelial growth factor (VEGF).gamma CdcPLI was also able to decrease PGE2 levels in MDA-MB-231 and inhibited gene and protein expression of the PI3K/Akt pathway. In conclusion,gamma CdcPLI showed in vitro antitumoral, antimestatatic and anti-angiogenic potential effects and could be an attractive approach for futures studies in cancer therapy.

Determinação das concentrações plasmáticas de proteínas e metabólitos de cascavéis em cativeiro / Determination of proteins and metabolites concentrations in plasma of rattlesnakes in captivity

Para determinar as concentrações plasmáticas de proteínas e metabólitos de cascavéis em cativeiro, foram utilizadas 60 serpentes adultas, sendo 30 machos e 30 fêmeas. O sangue foi coletado através de punção do seio venoso paravertebral cervical e armazenado em tubos com heparina. As análises bioquímicas foram processadas colorimetricamente em Analisador Automático de Bioquímica Chemwell (Awareness Technology®, Inc). Foram calculadas as médias e desvios padrão dos seguintes constituintes: proteínas totais, albumina, globulinas, relação albumina/globulinas, ácido úrico, creatinina, ureia, colesterol, colesterol HDL e triglicérides. Os valores obtidos foram semelhantes aos descritos na literatura para repteis e serpentes, sendo as diferenças observadas provavelmente decorrentes da diferença entre espécies, clima, estação do ano e metodologia utilizada. Não houve diferenças significativas entre machos e fêmeas para os parâmetros estudados. Estes resultados podem ser úteis no estabelecimento de valores de referência para planos de conservação destes ofídios em cativeiro.(AU)

For determining plasma concentrations of proteins and metabolites of rattlesnakes in captivity, 60 adult snakes, 30 males and 30 females were used. Blood was collected by puncture of the cervical paravertebral venous sinus and stored in tubes with heparin. Biochemical analyzes were colorimetrically processed using an Automatic Biochemistry Analyzer Chemwell (Awareness Technology®, Inc). The mean and standard deviation were calculated for the following constituents: total protein, albumin, globulin, albumin/globulin ratio, uric acid, creatinine, urea, cholesterol, HDL cholesterol and triglycerides. The values were similar to those previously reported for reptiles and snakes, with the differences observed probably due to the difference between species, climate, season and the methodology used. There were no significant differences between males and females for the parameters studied. These results may be useful in establishing normal biochemical values for conservation plans for these snakes in captivity.(AU)

Medium and large-sized mammals of a fragment of cerrado in the Triângulo Mineiro region, southeastern Brazil / Mamíferos de médio e grande porte de um fragmento de cerrado na região do Triângulo Mineiro, sudeste do Brasil

This work was developed to determine the species richness and composition of medium and large-sized mammals and to evaluate spatial and seasonal distribution of the more frequent of these species in a fragment of Cerrado. The fieldwork was conducted at the Gloria Experimental Farm, a property of the Federal University of Uberlândia, from August, 2008 to October, 2009. Four sample sites were investigated including three physiognomies: gallery forest, cerrado sensu stricto and semi-deciduous forest. The surveys were conducted during the day and mammals were recorded through direct (visualizations and vocalizations) and indirect (tracks, feces, bones and fur) evidences. A total of 18 species was recorded (seven Orders and fourteen families) and the majority of them was classified as medium mammals. The highest relative frequencies were registered for Procyon cancrivorus, Dasypus novemcinctus, Myrmecophaga tridactyla and Chrysocyon brachyurus. The gallery forest showed the highest species richness. However, most species roamed over several physiognomies, indicating a generalist use of habitat. There was no significant difference in the seasonal distribution of the majority of the analyzed species. M. tridactyla, C. brachyurus, Lontra longicaudis e Pecari tajacu are endangered mammal species in the State of Minas Gerais. We conclude that the study area has a representative mammalian fauna and great potential for conservation biology, as indicated by the presence of threatened species.

Este trabalho foi desenvolvido para determinar a riqueza de espécies e composição de mamíferos de médio e grande porte e avaliar a distribuição espacial e temporal das espécies mais freqüentes em um fragmento de Cerrado. O trabalho de campo foi conduzido de Agosto de 2008 a Outubro de 2009, na Fazenda Experimental Gloria, uma propriedade da Universidade Federal de Uberlândia. Quatro sítios de amostragem foram investigados, incluindo três fitofisionomias: mata de galeria, cerrado sensu stricto e floresta semi- decídua. Os registros foram realizados durante o dia e mamíferos foram registrados através evidência direts (visualizações e vocalizações) e indiretas (trilhas , fezes , ossos e pele ). Um total de 18 espécies foi registrado (sete ordens e quatorze famílias), sendo a maioria delas classificada como mamíferos de médio porte. As maiores freqüências relativas foram registradas para Procyon cancrivorus, Dasypus novemcinctus, Myrmecophaga tridactyla e Chrysocyon brachyurus. A mata de galeria a maior riqueza de espécies. No entanto, a maioria das espécies percorria várias fisionomias, indicando um uso generalista de habitat. Não houve diferença significativa na distribuição sazonal da maioria das espécies analisadas. M. tridactyla, C. brachyurus, Lontra longicaudis e Pecari tajacu são espécies ameaçadas de mamíferos no Estado de Minas Gerais. Conclui-se que a área de estudo tem uma fauna de mamíferos representativa e grande potencial para conservação biológica, como indicado pela presença de espécies ameaçadas.

Isolation and biochemical characterization of a γ-type phospholipase A2 inhibitor from Crotalus durissus collilineatus snake serum.

In the present work, we describe the isolation and partial structural and biochemical characterization of the first phospholipase A2 inhibitor (γPLI) from Crotalus durissus collilineatus (Cdc) snake serum. Initially, the Cdc serum was subjected to a Q-Sepharose ion exchange column, producing six peaks at 280 nm absorbance (Q1-Q6). Subsequently, Q4 fraction was submitted to affinity chromatography with immobilized PLA2 BnSP-7, a step that resulted in two fractions (NHS-1 and NHS-2). The latter contained the inhibitor, denominated γCdcPLI. The molecular mass of γCdcPLI, determined by Matrix-Assisted Laser Desorption Ionization Time-of-Flight (MALDI-TOF), was 22,340 Da. Partial sequences obtained by Edman degradation and by mass spectrometry (MALDI-TOF/TOF), showed similarity, as expected, to other related inhibitors. Circular dichroism (CD) analysis showed the presence of approximately 22% alpha helices and 29% beta sheets in the protein secondary structure. Additionally, CD studies also indicated no significant changes in the secondary structure of γCdcPLI when it is complexed to BpPLA2-TXI. On the other hand, dynamic light scattering (DLS) assays showed a temperature-dependent oligomerization behavior for this inhibitor. Biochemical analyses showed γCdcPLI was able to inhibit the enzymatic, cytotoxic and myotoxic activities of PLA2s. Structural and functional studies performed on this inhibitor may elucidate the action mechanisms of PLA2 inhibitors. In addition, we hope this study may contribute to investigating the potential use of these inhibitors for the treatment of snakebite or inflammatory diseases in which PLA2s may be involved.

Impacto antrópico na dieta do cágado-de-barbicha [Phrynops geoffroanus - Chelidae] no rio Uberabinha, Uberlândia, Minas Gerais, Brasil / Human impact on the diet of geoffroy's toadhead turtle [phrynops geoffroanus - Testudines, Chelidae] in the river Uberabinha, Uberlândia, Minas gerais, Brazil / Impacto antropico en la dieta de la tortuga de barbilla, [Phrynopsgeoffroanus - Testudines, Chelidae] en el rio Uberabinha, uberlândia, Minas Gerais, Brasil

Os Testudines (répteis caracterizados pela presença de uma carapaça) são uns dos principais componentes das redes tróficas dos rios, apesar disto, ainda é rara a observação dos cágados se alimentando em condições naturais. De maio a outubro de 2011 foi capturado um total de 110 espécimes de (cágado-de-barbicha) [Phrynops geoffroanus, Schweigger, 1812] do rio Uberabinha Minas Gerais, em três áreas distintas e também as presas em potenciais (peixes, macroinvertebrados e invertebrados terrestres). A coleta dos itens ingeridos foi realizada por meio de lavagem estomacal e para a coleta das presas em potencial foi utilizado armadilha tipo pitfall, rede D e armadilha tipo covo. Os itens da dieta foram fixados, identificados, separados em categorias e tiveram seus volumes aferidos. Para verificar se as diferentes áreas interferiram na dieta realizou- -se uma ANOVA Fatorial. Uma das áreas (área 3) não foi incluída nos testes estatísticos pela grande discrepância entre o número de fêmeas e machos capturados. Considerando a dieta como um todo, não houve diferença significativa entre as áreas 1 e 2 (F=3,342, p=0,068), mas ao se analisar separadamente cada categorias de itens alimentares, os espécimes da área 1 consumiram mais vertebrados aquáticos e menos itens de origem antrópica quando comparados com os espécimes da área 2 (F=65,419, p<0,01). Com relação ao sexo, não houve diferença estatística na área 1 (F=0,561, p= 0,454), mas houve na área 2 (F= 9,410, p=0,02), sendo que as fêmeas consumiram maior volume de itens de origem antrópica do que os machos (F= 34,276, p<0,001). A dieta diversificada e a adaptação a ambientes impactados demonstram que P. geoffroanus é uma espécie com grande plasticidade.

The Testudines (reptiles characterized by the presence of a shell) are a major component of trophic networks in rivers. Nonetheless, it is still rare to see turtles feeding in natural conditions. From May to October 2011, a total of 110 specimens of P. geoffroanus were captured in River Uberabinha, in three distinct areas, as well as capturing their potential prey (fish, macro-invertebrates and terrestrial invertebrates). The collection of ingested items was performed by stomach flushing, and the collection of potential prey was made with pitfall traps, D nets and “Covo” trap. The dietary items were fixed, marked, separated into categories, and their volumes were measured. In order to verify if the different areas affect the diet, ANOVA factorial was performed. One of the areas (area 2) was not included in the statistical tests due to the large discrepancy between the number of females and males captured. Considering the diet as a whole, there were no significant differences between areas 1 and 2 (F=3.342, p=0.068), but when they were analyzed separately for each food item categories, the specimens from area 1 consumed more aquatic vertebrates and fewer items from anthropogenic origin when compared to specimens from area 2 (F=65.419, p<0.01). Regarding gender, no statistical differences were found in area 1 (F=0.561, p= 0.454), but statistical difference was found in area 2 (F= 9.410, p=0.02), being that females consumed a greater volume of items from anthropogenic origin than males (F= 34.276, p<0.001). The diversified diet and adaptation to impacted environments demonstrate that P. geoffroanus is a species with high plasticity.

Los Testudines (reptiles caracterizados por la presencia de un caparazón) son algunos de los principales componentes de las redes tróficas de los ríos, a pesar de esto, todavía es rara la observación de las tortugas alimentándose en condiciones naturales. De mayo a octubre de 2011 fueron capturados un total de 110 especímenes de tortuga de barbilla (Phrynopsgeoffroanus, Schweigger, 1812) del río Uberabinha – Minas Gerais, en tres áreas distintas y también las presas potenciales (peces, macroinvertebrados e invertebrados terrestres). La colecta de los ítems ingeridos se ha realizado por medio de lavaje estomacal y para la colecta de las presas potenciales se ha utilizado una trampa tipo “pitfall”, “red D” y trampa tipo “embudo”. Los ítems de la dieta fueron fijados, identificados, separados en categorías y tuvieron sus volúmenes medidos. Para verificar si las diferentes áreas interfirieron en la dieta se realizó un ANOVA Factorial. Una de las áreas (área 3) no fue incluida en los testes estadísticos debido gran discrepancia entre el número de hembras y de machos capturados. Considerando la dieta como un todo, no hubo diferencia significativa entre las áreas 1 y 2 (F=3,342, p=0,068), pero al analizar separadamente cada categoría de ítems alimenticios, los especímenes del área 1 consumieron más vertebrados acuáticos y menos ítems de origen antrópica comparados con los especímenes del área 2 (F=65,419, p<0,01). Con relación al sexo, no hubo diferencia estadística en el área 1 (F=0,561, p= 0,454), pero hubo en el área 2 (F= 9,410, p=0,02), siendo que las hembras consumieron mayor volumen de ítems de origen antrópica que los machos (F= 34,276, p<0,001). La dieta diversificada y la adaptación a ambientes impactados demuestran que P. geoffroanus es una especie con gran plasticidad.

Anaphylaxis in pregnancy: a rare cause of neonatal mortality.

Anaphylaxis is a rare condition in pregnancy. Drugs are the aetiological agents most often implicated. Maternal anaphylaxis can lead to significant fetal morbidity and even mortality if uterine perfusion and maternal oxygenation are compromised. Significant risk of neonatal neurological damage or death can occur even when the maternal clinical outcome is favourable. The authors present the case of a newborn, born at gestational age of 29 weeks, who died at 11 days of life with hypoxic-ischaemic cerebral injuries as a consequence of maternal anaphylaxis following the administration of amoxicillin in the community setting.

Distribuição espacial e dinâmica temporal da alga epizoária Basicladia chelonum associada ao cágado Phrynops geoffroanus no rio Uberabinha, Minas Gerais. Uberlândia, 2006, 52P. dissertação (Mestrado Em Ecologia E Conservação De Recursos Naturais) Universidade Federal de Uberlândia / Distribución espacial y dinámica temporal de alga epizoária Basicladia chelonum asociada a la tortuga Phrynops geoffroanus en el río Uberabinha, Minas Gerais / Space distribution and storm dynamics of Basicladia chelonum epizoic algae associate with Phrynops geoffroanus freshwater turtle in the Uberabinha River, Minas Gerais, Uberlândia, 2006, 52p. Thesis (Master In Ecology And Conservation of Natural Resources) - Universidade Federal de Uberlândia

Foram realizados estudos da alga Basicladia chelonum sobre a carapaça de Phrynops geoffroanus no rio Uberabinha, Uberlândia (18°54’34,5’’S e 48°18’20,4’’W), Brasil. Os trabalhos de campo foram realizados de agosto de 2004 a junho de 2005, juntamente com estudos de alguns parâmetros físicos do ar e físicos e químicos da água. Foram capturados 320 Phrynops geoffroanus (205 fêmeas, 115 machos; 40 espécimes/coleta). As algas da carapaça foram plotadas em folhas de acetato e a área da cobertura algácea estimada em AutoCAD 2002. Amostras das algas foram coletadas, fixadas e analisadas quanto: presença de esporângios, altura e comprimento e diâmetro das células. Foram constatadas correlações entre: temperatura do ar/temperatura da água; oxigênio dissolvido/pH e DQO; precipitação/concentrações de ferro e amônio; condutividade elétrica/ pH, sólidos totais dissolvidos, turbidez e concentrações de nitrato, nitrito, ferro e amônio. A cobertura foi maior em setembro e menor em março e junho (F=2,28; p<0,05). Os machos apresentaram maior cobertura que as fêmeas (F=8,60; p<0,05). Ocorreu um maior número de indivíduos com algas nos escudos marginais posteriores e menor nos marginais anteriores e da ponte (F=35,27; p<0,05). Os esporângios foram mais abundantes em setembro (F=5,86; p<0,05) e nos escudos marginais anteriores (F=114,62; p<0,05), e mais raros em agosto, outubro, março e junho (F=4,85; p<0,05) e nos escudos costais, marginais anteriores e nos vertebrais (F=54,13; p<0,05). A sazonalidade não interferiu na dinâmica populacional da alga, embora tenha variado durante o período. Abrasão, turbulência e concentração de nutrientes da água podem ter interferido na cobertura algácea dos cágados.

Studies were developed about a population of Basicladia chelonum algae over the Phrynops geoffroanus carapace in Uberabinha River, Uberlândia (18°54’34,5’’S e 48°18’20,4’’W), Brasil. The work was accomplished from August 2004 to June 2005, together with some physical of air and physical and chemical water parameters. Three hundred and twenty Phrynops geoffroanus (205 female; 115 males; 40 specimens/collect) were captured. The algae of carapace were plotted in acetate sheets and the area of algae covering was estimated in AutoCAD 2002. Samples of algae were collected, fixed and analyzed as: presence of sporangium, height and length and diameter of cells. Were found correlations between: air temperature/water temperature; dissolved oxygen/pH and oxygen chemical demand; precipitation/concentration of iron and ammonium; electrical conductivity/pH, totals solids dissolved, turbidity and concentrations of nitrate, nitrite, iron and ammonium. The coverage was higher in September and lower in March and June (F=2,28; p<0,05). The males showed more coverage than female (F=8,60; p<0,05). Occurred a higher number of individuals with in the posterior marginal shield and lower in the anterior marginal shield and in the bridge (F=35,27; p<0,05). Sporangium´s were more abundant in September (F=5,86; p<0,05) and in the anterior marginal shield (F=114,62; p<0,05), and rare in August, October, March and June (F=4,85; p<0,05) and in the costal shield, anterior marginal and in the vertebral (F=54,13; p<0,05). The seasonality did not interfere in the populational dynamics of algae although it had varied during the period. Abrasion, turbulence and concentration of nutrients the water could be interfering in algae coverage of the turtle.

Se realizaron estudios de algas Basicladia chelonum sobre el caparazón de Phrynops geoffroanus en el río Uberabinha, Uberlândia (18°54’34,5’’S y 48°18’20,4’’W), Brasil. Los trabajos de campo se realizaron de agosto de 2004 a junio de 2005, juntamente con estudios de algunos parámetros físicos del aire y físicos-químicos del agua. Fueron capturados 320 Phrynops geoffroanus (205 hembras, 115 machos; 40 especímenes/colecta). Las algas del caparazón fueron marcadas en hojas de acetato y el área de cobertura con algas estimada en AutoCAD 2002. Muestras de las algas fueron colectadas, fijadas y analizadas cuanto a: presencia de esporangios, altura y longitud, y diámetro de las células. Se constató correlaciones entre: temperatura del aire/ temperatura del agua; oxigeno disuelto/ pH y DQO; precipitación/concentraciones de hierro y amonio; conductividad eléctrica/pH, sólidos totales disueltos, turbidez y concentraciones de nitrato, nitrito, hierro y amonio. La cobertura fue mayor en septiembre y menor en marzo y junio (F=2,28; p<0,05). Los machos presentaron mayor cobertura que las hembras (F=8,60; p<0,05). Ocurrió un mayor número de individuos con algas en los escudos marginales posteriores y menor en los marginales anteriores y del puente (F=35,27; p<0,05). Los esporangios fueron más abundantes en septiembre (F=5,86; p<0,05) y en los escudos marginales anteriores (F=114,62; p<0,05), y más raros en agosto, octubre, marzo y junio (F=4,85; p<0,05) y en los escudos costales, marginales anteriores y en los vertebrales (F=54,l3; p<0.05). La estacionalidad no afectó en la dinámica poblacional del alga, aunque haya variado durante el periodo. Abrasión, turbulencia y concentración de nutrientes del agua pueden haber interferido en la cobertura de algas de las tortugas.

Distribuição espacial e dinâmica temporal da alga epizoária Basicladia chelonum associada ao cágado Phrynops geoffroanus no rio Uberabinha, Minas Gerais, Uberlândia / Spatial and temporal dynamics of Basicladia chelonum epizoic algae associate with Phrynops geoffroanus freshwater turtle in the Uberabinha River, Minas Gerais, Uberlândia / Distribución espacial y dinámica temporal de alga epizoária Basicladia chelonum asociada a la tortuga Phrynops geoffroanus en el Río Uberabinha, Minas Gerais, Uberlândia

Foram realizados estudos da alga Basicladia chelonum sobre a carapaça de Phrynops geoffroanus no rio Uberabinha, Uberlândia (18°54’34,5”S e 48°18’20,4”W), Brasil. Os trabalhos de campo foram realizados de agosto de 2004 a junho de 2005, juntamente com estudos de alguns parâmetros físicos do ar e físicos-químicos da água. Foram capturados 320 Phrynops geoffroanus (205 fêmeas, 115 machos; 40 espécimes/coleta). As algas da carapaça foram plotadas em folhas de acetato e a área da cobertura algácea estimada em AutoCAD 2002. Amostras das algas foram coletadas, fixadas e analisadas quanto a: presença de esporângios, altura e comprimento e diâmetro das células. Foram constatadas correlações entre: temperatura do ar/temperatura da água; oxigênio dissolvido/pH e DQO; precipitação/concentrações de ferro e amônio; condutividade elétrica/pH, sólidos totais dissolvidos, turbidez e concentrações de nitrato, nitrito, ferro e amônio. A cobertura foi maior em setembro e menor em março e junho (F=2,28; p<0,05). Os machos apresentaram maior cobertura que as fêmeas (F=8,60; p<0,05). Ocorreu um maior número de indivíduos com algas nos escudos marginais posteriores e menor nos marginais anteriores e da ponte (F=35,27; p<0,05). Os esporângios foram mais abundantes em setembro (F=5,86; p<0,05) e nos escudos marginais anteriores (F=114,62; p<0,05), e mais raros em agosto, outubro, março e junho (F=4,85; p<0,05) e nos escudos costais, marginais anteriores e nos vertebrais (F=54,13; p<0,05). A sazonalidade não interferiu na dinâmica populacional da alga, embora tenha variado durante o período. Abrasão, turbulência e concentração de nutrientes da água podem ter interferido na cobertura algácea dos cágados.

Studies were developed about a population of Basicladia chelonum algae over the Phrynops geoffroanus carapace in Uberabinha River, Uberlândia (18°54’34,5”S and 48°18’20,4”W), Brazil. Field work was accomplished from August 2004 to June 2005, together with some physical parameters of the air and physical and chemical parameters of the water. Three hundred and twenty Phrynops geoffroanus (205 female; 115 males; 40 specimens/collection) were captured. The algae of carapace were plotted in acetate sheets and the area of algae covering was estimated in AutoCAD 2002. Samples of algae were collected, fixed and analyzed as: presence of sporangium, height and length and diameter of cells. Correlations were found for: air temperature/water temperature; dissolved oxygen/pH and oxygen chemical demand; precipitation/concentration of iron and ammonium; electrical conductivity/pH, totals solids dissolved, turbidity and concentrations of nitrate, nitrite, iron and ammonium. The coverage was higher in September and lower in March and June (F=2.28; p<0.05). The males showed more coverage than female (F=8.60; p<0.05). Higher number of individuals with in the posterior marginal shield and lower in the anterior marginal shield and bridge (F=35.27; p<0.05) were found. Sporangia were more abundant in September (F=5.86; p<0.05) and in the anterior marginal shield (F=114.62; p<0.05), and rare in August, October, March and June (F=4.85; p<0.05) and in the costal shield, anterior marginal and in the vertebral (F=54.13; p<0.05). The seasonality did not interfere with the population dynamics of algae although it had varied during the period. Abrasion, turbulence and concentration of nutrients in the water may have interfered in algal coverage of the turtle.

Fueron realizados estudios de algas Basicladia chelonum sobre el caparazón de Phrynops geoffroanus en el río Uberabinha, Uberlândia (18°54’34,5”S y 48°18’20,4”W), Brasil. Los trabajos de campo fueron realizados de agosto de 2004 a junio de 2005, juntamente con estudios de algunos parámetros físicos del aire y físicos-químicos del agua. Fueron capturados 320 Phrynops geoffroanus (205 hembras, 115 machos; 40 especimenes /colecta). Las algas del caparazón fueron marcadas en hojas de acetato y el área de cobertura algácea estimada en AutoCAD 2002. Muestras de las algas fueron colectadas, fijadas y analizadas cuanto a: presencia de esporangios, altura y longitud y diámetro de las células. Fueron constatadas correlaciones entre: temperatura del aire/temperatura del agua; oxigeno disuelto/pH y DQO; precipitación/concentraciones de hierro y amonio; conductividad eléctrica/pH, sólidos totales disueltos, turbidez y concentraciones de nitrato, nitrito, hierro y amonio. La cobertura fue mayor en septiembre y menor en marzo y junio (F=2,28; p<0,05). Los machos presentaron mayor cobertura que las hembras (F=8,60; p<0,05). Ocurrió un mayor número de individuos con algas en los escudos marginales posteriores y menor en los marginales anteriores y del puente (F=35,27; p<0,05). Los esporangios fueron más abundantes en septiembre (F=5,86; p<0,05) y en los escudos marginales anteriores (F=114,62; p<0,05), y más raros en agosto, octubre, marzo y junio (F=4,85; p<0,05) y en los escudos costales, marginales anteriores y en los vertebrales (F=54,13; p<0,05). La estacionalidad no afectó en la dinámica poblacional del alga, aunque haya variado durante el período. Abrasión, turbulencia y concentración de nutrientes del agua pueden haber interferido en la cobertura algácea de las tortugas.

The influence of agricultural and urban contamination on leech infestation of freshwater turtles, Phrynops geoffroanus, taken from two areas of the Uberabinha River.

Infestation by leeches on adult freshwater turtles Phrynops geoffroanus in two areas of the Uberabinha River, in Uberlândia, was investigated during the summer (January 2000). Fifty eight turtles were trapped: 26 (12 males, 14 females) in an agricultural area and 32 (16 males, 16 females) in an area with a more urban environment. The females present larger length and body mass (291.77+/-29.18 mm; 2233.30+/-511.40 g) than males (259.71+/-33.15 mm; 1488.68+/-529.35 g). Blood samples were drawn from the retrorbital sinus using heparinized micro-hematocrit capillary tubes, for microscopic and direct examination for intracellular parasites. Ectoparasitism by leeches, Placobdella bistriata, on young and adult animals was observed in the limb cavities of 28.1% of the urban area turtles. No leeches were found on the turtles in the agricultural area. Hemogregarine erythrocytic gametocytes were found in 15.4% of the agricultural area turtles, and in 37.5% of the urban area turtles. Concurrent parasitism by leeches and hemogregarines on the same individuals was seen on six turtles. Infections with microorganisms (bacteria and fungus) facilitated by the bites of leeches were not observed in another study on the same sample of infested turtles. However, 19% of the turtles collected in the agricultural area and 15% of the turtles from the urban area presented normocytic acute anemia. The occupation of the soil apparently interfered in the aquatic ecosystem favoring parasitism in the urban area.