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1.
J Healthc Qual Res ; 38(1): 20-25, 2023.
Article in English | MEDLINE | ID: mdl-35835633

ABSTRACT

BACKGROUND: The impact of COVID-19 in families and patients with congenital diaphragmatic hernia (CDH) is unknown, this situation has generated uncertainty not only in family members but also in the optimal outpatient follow-up. Telehealth has become a fundamental tool for the follow-up during the pandemic. The objective of this survey is to evaluated the impact of SARS-CoV-2 in families and patients with CDH and the satisfaction with telematic follow-up. METHODS: Telephone survey of patient's caregivers with CHD, aged 1-16 years, followed in neonatal surgery outpatients, from January 31, 2020 to November 15, 2020. The ethical clearance for this study was taken from the Clinical Research Ethics Committee of our Research Institute vide letter number VHIR/239283/01.01.2021. RESULTS: 81 surveys of 100 patients with active follow-up were carried out. There were no refusals in any contacted parents. There were 30 contacts (37%), 44.8% at school and 27.6% from cohabiting family members. Four infections (4.9%) were diagnosed, half symptomatic. In 40 patients (49.4%) the follow-up was telematic, with a mean score of 3.1±1.3 out of 5. For future controls, 65% prefer presential follow-up, 25% alternate and 10% telematics. 50.6% reported greater anxiety and 34.6% (28/81) extreme measures of isolation, being more accentuated in the group of 3-6 years (p<0.05). CONCLUSION: The impact of COVID19 in patients with CHD is not greater than in the general pediatric population. Although the incorporation of the telehealth was well valued, most of the caregivers prefer the face-to-face outpatient follow-up.


Subject(s)
COVID-19 , Hernias, Diaphragmatic, Congenital , Infant, Newborn , Humans , Child , SARS-CoV-2 , Hernias, Diaphragmatic, Congenital/diagnosis , Hernias, Diaphragmatic, Congenital/surgery , COVID-19/epidemiology , Follow-Up Studies , Pandemics , Patient Satisfaction , Personal Satisfaction
2.
Cir Pediatr ; 35(1): 31-35, 2022 Jan 01.
Article in English, Spanish | MEDLINE | ID: mdl-35037438

ABSTRACT

INTRODUCTION: Duodenal atresia associated with apple peel is extremely rare. Duodenal atresia occurs as a result of absence of recanalization at an early stage, whereas intestinal atresia is seemingly due to vascular causes at later stages. The presence of abnormalities associated with diaphragmatic hernia is frequent, but association with duodenal atresia has been little explored. CASE REPORT: This is the case of a female neonate born at gestational week 31, with duodenal atresia and apple peel, associated with left diaphragmatic hernia and major heart disease. An abdominal muscle flap was performed for diaphragmatic defect closure purposes, and duodenojejunal anastomosis was carried out following resection of part of the non-viable apple peel. DISCUSSION: To our knowledge, this is the first case described with this rare association. The combination of duodenal atresia and apple peel had been previously described 11 times. However, the association of both with congenital diaphragmatic hernia had not been reported yet.


INTRODUCCION: La atresia duodenal asociada con appel peel es extremadamente infrecuente. La primera se produce por un defecto en la recanalización en etapas tempranas, mientras que la atresia intestinal parece deberse a causas vasculares en etapas más tardías. La presencia de anomalías asociadas a la hernia diafragmática es común, pero la asociación con la atresia duodenal apenas está descrita. CASO CLINICO: Presentamos un recién nacido de 31 semanas de gestación y sexo femenino, con atresia duodenal y apple peel, asociada a hernia diafragmática izquierda y cardiopatía mayor. Se realizó un flap muscular abdominal para el cierre del defecto diafragmático y anastomosis duodenoyeyunal tras la resección de parte del apple peel inviable. COMENTARIOS: A nuestro entender, es el primer caso descrito con esta asociación singular. La combinación de atresia duodenal con apple peel se ha descrito previamente en 11 ocasiones; la asociación de ambas con hernia diafragmática congénita no había sido descrita.


Subject(s)
Duodenal Obstruction , Hernias, Diaphragmatic, Congenital , Intestinal Atresia , Malus , Duodenal Obstruction/etiology , Duodenal Obstruction/surgery , Female , Hernias, Diaphragmatic, Congenital/surgery , Humans , Intestinal Atresia/surgery
3.
Cir. pediátr ; 35(1): 1-5, Enero, 2022. tab, ilus
Article in Spanish | IBECS | ID: ibc-203586

ABSTRACT

Introducción: La atresia duodenal asociada con appel peel es extremadamente infrecuente. La primera se produce por un defecto en larecanalización en etapas tempranas, mientras que la atresia intestinalparece deberse a causas vasculares en etapas más tardías. La presenciade anomalías asociadas a la hernia diafragmática es común, pero laasociación con la atresia duodenal apenas está descrita.Caso clínico: Presentamos un recién nacido de 31 semanas de gestación y sexo femenino, con atresia duodenal y apple peel, asociada ahernia diafragmática izquierda y cardiopatía mayor. Se realizó un flapmuscular abdominal para el cierre del defecto diafragmático y anastomosis duodenoyeyunal tras la resección de parte del apple peel inviable.Comentarios: A nuestro entender, es el primer caso descrito conesta asociación singular. La combinación de atresia duodenal con apple peel se ha descrito previamente en 11 ocasiones; la asociación de ambascon hernia diafragmática congénita no había sido descrita.


Introduction: Duodenal atresia associated with apple peel is extremely rare. Duodenal atresia occurs as a result of absence of recanali-zation at an early stage, whereas intestinal atresia is seemingly due tovascular causes at later stages. The presence of abnormalities associatedwith diaphragmatic hernia is frequent, but association with duodenalatresia has been little explored.Care report: This is the case of a female neonate born at gestational week 31, with duodenal atresia and apple peel, associated withleft diaphragmatic hernia and major heart disease. An abdominal muscle flap was performed for diaphragmatic defect closure purposes, and duodenojejunal anastomosis was carried out following resection of partof the non-viable apple peel.Discussion: To our knowledge, this is the first case described with this rare association. The combination of duodenal atresia and applepeel had been previously described 11 times. However, the associationof both with congenital diaphragmatic hernia had not been reported yet.


Subject(s)
Humans , Female , Infant, Newborn , Intestinal Atresia , Duodenal Obstruction/surgery , Duodenal Obstruction/etiology , Hernia, Diaphragmatic/surgery , Infant, Newborn , Rare Diseases , Pediatrics
4.
Environ Monit Assess ; 193(8): 535, 2021 Jul 29.
Article in English | MEDLINE | ID: mdl-34327557

ABSTRACT

Birds are widely used as bioindicators in monitoring programs in wetlands. We compare concentrations of seven trace metals and metalloids (TMM) As, Cd, Cu, Fe, Hg, Pb, Znin both feathers and blood in two flamingo species in two high-altitude wetlands in Bolivia, with different levels of anthropogenic point source pollution. Lake Uru Uru (LUU) receives discharges from mining operations, and also effluents from the nearby city of Oruro, while Laguna Colorada (LCo) does not receive contaminants from anthropogenic sources. We sampled water and sediments at each site, as well as flamingos in three age classes in an effort to establish a benchmark for long-term monitoring. Metal concentrations in water did not differ between sites, whereas Zn and Pb concentrations of TMM in sediments were higher at LUU, and Hg higher at LCo. TMM concentrations were highly specific for all separate elements, but results point to differences between Andean flamingo (Phoenicoparrus andinus) chicks and the rest of the classes considered. As flamingo chicks did not molt before sampling, we pose that TMM concentrations in their blood and feathers may respond mainly to local conditions. Eggshells provide additional information, since adults transfer some TMM during egg development. Long-term monitoring in these species should include different age classes and sample both feathers and eggshells to monitor the environmental conditions and bioaccumulation of TMM in these species. Future studies should include sites devoid of natural sources of TMM to help distinguish sources of contamination, since some TMM (As and Pb) may be naturally in high concentrations in remote areas, like Laguna Colorada.


Subject(s)
Metalloids , Metals, Heavy , Animals , Birds , Bolivia , Cities , Environmental Monitoring , Metals, Heavy/analysis , Wetlands
5.
Front Pharmacol ; 12: 782095, 2021.
Article in English | MEDLINE | ID: mdl-35111053

ABSTRACT

The tissue engineering of dental oral tissue is tackling significant advances and the use of stem cells promises to boost the therapeutical approaches of regenerative dentistry. Despite advances in this field, the literature is still scarce regarding the modulatory effect of laser photobiomodulation (PBM) on genes related to inflammation and osteogenesis in Postnatal Human Dental Pulp Stem cells (DPSCs). This study pointedly investigated the effect of PBM treatment in proliferation, growth and differentiation factors, mineralization, and extracellular matrix remodeling genes in DPSCs. Freshly extracted human third molars were used as a source for DPSCs isolation. The isolated DPSCs were stimulated to an inflammatory state, using a lipopolysaccharide (LPS) model, and then subjected or not to laser PBM. Each experiment was statistically evaluated according to the sample distribution. A total of 85 genes related to inflammation and osteogenesis were evaluated regarding their expression by RT-PCR. Laser PBM therapy has shown to modulate several genes expression in DPSCs. PBM suppressed the expression of inflammatory gene TNF and RANKL and downregulated the gene expression for VDR and proteolytic enzymes cathepsin K, MMP-8 and MMP-9. Modulation of gene expression for proteinase-activated receptors (PARs) following PBM varied among different PARs. As expected, PBM blocked the odontoblastic differentiation of DPSCs when subjected to LPS model. Conversely, PBM has preserved the odontogenic potential of DPSCs by increasing the expression of TWIST-1/RUNEX-2/ALP signaling axis. PBM therapy notably played a role in the DPSCs genes expression that mediate inflammation process and tissue mineralization. The present data opens a new perspective for PBM therapy in mineralized dental tissue physiology.

6.
Environ Sci Pollut Res Int ; 25(14): 13292-13311, 2018 May.
Article in English | MEDLINE | ID: mdl-27761862

ABSTRACT

The aim of this study was to jointly show the results of three independent ecotoxicological studies performed to investigate pollutants in three Brazilian tropical reservoirs undergoing accelerated eutrophication. In order to accomplish this goal, the full toxicity identification and evaluation procedure (TIE approach) was performed, at Pampulha (Minas Gerais State) and Salto Grande and Barra Bonita reservoirs (São Paulo State). Acute and chronic toxicity tests were performed using the cladocerans Daphnia similis and Ceriodaphnia dubia (exotic) and Daphnia laevis and Ceriodaphnia silvestrii (native) as test organisms. Results from TIE procedure stage I indicated the existence of nonpolar organic and filterable compounds in the water from Pampulha, probably cyanotoxins, and oxidants as part of the toxic agents. TIE results for sediments identified ammonia (Pampulha and Salto Grande), organic compounds (Pampulha), metals (Pampulha, Barra Bonita, and Salto Grande), and acidity (Salto Grande) as responsible for toxicity. Whole-sediment remediation experiments for Pampulha reservoir confirmed, through reproduction decrease, ammonia and organic compounds as contaminants. Such pollutants represent threats to aquatic biota and must be prevented. Higher temperatures as predicted from global climate change will severely affect tropical shallow reservoirs, accelerating eutrophication, the release of contaminants from sediments, and increasing toxicity.


Subject(s)
Eutrophication , Fresh Water/analysis , Geologic Sediments/chemistry , Animals , Brazil , Cladocera/drug effects , Daphnia/drug effects , Ecotoxicology , Tropical Climate , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
7.
Braz. j. biol ; 77(4): 840-847, Nov. 2017. tab, graf
Article in English | LILACS | ID: biblio-888802

ABSTRACT

Abstract Cladocerans occupy an important position among the bacterial consumers in freshwater food webs, being relatively non-selective filter feeders that can exert a strong impact on microbial populations. We evaluated the bacterivory potential of three cladocerans species of subtropical and tropical occurrence (Ceriodaphnia silvestrii, Daphnia gessneri and Ceriodaphnia cornuta) at different life stages, by scanning electron microscopy (SEM) and by the quantification of their bacterial consumption rates using fluorescently labeled bacteria (FLB). All species showed filter mesh sizes sufficiently narrow to retain bacteria. The largest distance between setules was found in primiparous C. cornuta, and the smallest in neonate D. gessneri. The lowest ingestion (IR) and removal (RR) rates were observed in primiparous C. silvestrii and the highest values were observed in adults of D. gessneri. We conclude that bacteria may be considered an important food supplement, particularly for neonates who presented smaller intersetular distances and higher filtration rates than the other life stages.


Resumo Dentre os diversos consumidores de bactérias nas teias alimentares de ambientes dulcícolas, os cladóceros ocupam uma posição relevante, sendo filtradores relativamente não seletivos que podem exercer forte impacto na redução populacional microbiana. Avaliamos o potencial bacterívoro de três espécies de cladóceros de ocorrência tropical e subtropical (Ceriodaphnia silvestrii, Ceriodaphnia cornuta e Daphnia gessneri) em diferentes fases de vida, através do estudo microscópico de suas estruturas filtradoras e da quantificação de suas taxas de ingestão em experimentos de bacterivoria utilizando-se bactérias marcadas fluorescentemente (FLB). As espécies estudadas mostraram ter uma rede de malhas filtradoras suficientemente estreitas para reter bactérias. A maior distância entre as sétulas foi encontrada em primíparas de C. cornuta, e a menor em neonatos de D. gessneri. As menores Taxas de Ingestão (TI) e Remoção (TR) foram observadas em primíparas de C. silvestrii e as maiores em adultas de D. gessneri. Concluímos que as bactérias podem ser consideradas um importante suplemento alimentar, principalmente para neonatos, que apresentaram pequenas distâncias intersetulares e altas taxas de ingestão comparadas aos outros estágios de vida.


Subject(s)
Animals , Bacteria , Food Chain , Cladocera/physiology , Daphnia/physiology , Feeding Behavior
8.
Braz J Biol ; 77(4): 840-847, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28355388

ABSTRACT

Cladocerans occupy an important position among the bacterial consumers in freshwater food webs, being relatively non-selective filter feeders that can exert a strong impact on microbial populations. We evaluated the bacterivory potential of three cladocerans species of subtropical and tropical occurrence (Ceriodaphnia silvestrii, Daphnia gessneri and Ceriodaphnia cornuta) at different life stages, by scanning electron microscopy (SEM) and by the quantification of their bacterial consumption rates using fluorescently labeled bacteria (FLB). All species showed filter mesh sizes sufficiently narrow to retain bacteria. The largest distance between setules was found in primiparous C. cornuta, and the smallest in neonate D. gessneri. The lowest ingestion (IR) and removal (RR) rates were observed in primiparous C. silvestrii and the highest values were observed in adults of D. gessneri. We conclude that bacteria may be considered an important food supplement, particularly for neonates who presented smaller intersetular distances and higher filtration rates than the other life stages.


Subject(s)
Bacteria , Cladocera/physiology , Food Chain , Animals , Daphnia/physiology , Feeding Behavior
9.
Sci Total Environ ; 575: 876-886, 2017 Jan 01.
Article in English | MEDLINE | ID: mdl-27712868

ABSTRACT

We used fine root and litter mass from a tropical mountain cloud forest to assess their relative contribution to nutrient content and to examine mineralization processes during a laboratory incubation experiment. Our results showed that average fine root mass density ranged from 2.86kgm-3 to 11.59kgm-3, while litter mass density ranged from 72.5kgm-3 to 177.3kgm-3. On average, fine root mass density represented 4.7% of the mass density of the O horizon. Fine root mass density followed an exponentially declining trend with soil depth. On average, 83% of fine root mass density within the soil profile was concentrated in the O horizon. Mean element pools in litter decreased from 44.08mgcm-3 to 0.49µgcm-3 in the following sequence: C>N>Fe>S>Ca>P>K>Mg>Na>Mn>Zn>Cu. For fine roots, a different mean element pool sequence (C>N>Ca>K>Fe>S>Mg>Na>P>Mn>Zn>Cu) in decreasing abundance (from 2.88mgcm-3 to 0.13µgcm-3) was observed with respect to litter. Regarding C, litter mineralized faster than fine roots, with a mean k value of 0.25d-1 for litter and 0.13d-1 for fine roots. Principal component analysis (PCA) combined with stepwise regression analysis revealed that the main mass density predictors were N, S, Zn, and Mn for litter (p<0.0001, R2=0.92), and S and C/N ratio for fine roots (p<0.0001, R2=0.82). These results demonstrate the potential of chemical composition to influence the mineralization of fine root and litter mass and therefore the nutrient availability and C sequestration.

10.
Braz J Biol ; 75(3): 628-37, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26465725

ABSTRACT

The present study focuses on the structure and function of phytoplankton community during periods of marked changes in hydrological traits, influenced by an atypical climatic event (La Niña) and its impact on Armando Ribeiro Gonçalves Reservoir of Rio Grande do Norte, situated in the Caatinga biome of northeastern Brazil. The main questions addressed were: What are the effects of environmental factors on the temporal variation of Morphologically Based Functional Group (MBFG) of phytoplankton community? How does the composition of cyanobacterial species shift in relation to high and low trends of phytoplankton diversity? The samples were collected monthly during 2008-2009 and analyzed for pH, temperature, electrical conductivity, dissolved oxygen content and the nutrients, such as, nitrate-nitrogen, ammoniacal nitrogen, total nitrogen and orthophosphate. Phytoplankton samples were collected for both qualitative and quantitative analyses to evaluate species richness index and species diversity index. The data was divided into two distinct hydrodynamic periods of instability and stability. The results demonstrate considerable changes in dissolved oxygen content, water transparency and nitrogen nutrients, which directly influenced the MBFG of phytoplankton community in space and time. The instability of reservoir water was caused by heavy rainfall, which exerts atypical external disturbances. The seasonal variation of MBFG demonstrates a change in cyanobacterial composition and their diversity during instability and stability periods. MBFG VII, composed by colonial cyanobacteria with mucilage, was associated with reduced values of electrical conductance and alterations in pH. The predominance of filamentous species with heterocyst (MBFG III) occurs only during the hydrodynamic stability period and did not show significant association with analyzed parameters. The co-dominance of MBGFs III, V and VII along with high species diversity of phytoplankton community occurred during the second hydrodynamic instability period which was associated with the reduction in water temperature. It is concluded that the decrease in cyanobacterial species dominance and the general increase in the diversity of phytoplankton community are influenced by pluvial anomaly. The higher water level during the period of pluvial anomaly resulted in nutrient pulse and the mixing of water column in the reservoir, which determined the MBPG phytoplankton community distribution.


Subject(s)
Biodiversity , Cyanobacteria/physiology , El Nino-Southern Oscillation , Phytoplankton/physiology , Brazil , Lakes , Seasons
11.
Braz. j. biol ; 75(3): 628-637, Aug. 2015. tab, ilus
Article in English | LILACS | ID: lil-761570

ABSTRACT

AbstractThe present study focuses on the structure and function of phytoplankton community during periods of marked changes in hydrological traits, influenced by an atypical climatic event (La Niña) and its impact on Armando Ribeiro Gonçalves Reservoir of Rio Grande do Norte, situated in the Caatinga biome of northeastern Brazil. The main questions addressed were: What are the effects of environmental factors on the temporal variation of Morphologically Based Functional Group (MBFG) of phytoplankton community? How does the composition of cyanobacterial species shift in relation to high and low trends of phytoplankton diversity? The samples were collected monthly during 2008-2009 and analyzed for pH, temperature, electrical conductivity, dissolved oxygen content and the nutrients, such as, nitrate-nitrogen, ammoniacal nitrogen, total nitrogen and orthophosphate. Phytoplankton samples were collected for both qualitative and quantitative analyses to evaluate species richness index and species diversity index. The data was divided into two distinct hydrodynamic periods of instability and stability. The results demonstrate considerable changes in dissolved oxygen content, water transparency and nitrogen nutrients, which directly influenced the MBFG of phytoplankton community in space and time. The instability of reservoir water was caused by heavy rainfall, which exerts atypical external disturbances. The seasonal variation of MBFG demonstrates a change in cyanobacterial composition and their diversity during instability and stability periods. MBFG VII, composed by colonial cyanobacteria with mucilage, was associated with reduced values of electrical conductance and alterations in pH. The predominance of filamentous species with heterocyst (MBFG III) occurs only during the hydrodynamic stability period and did not show significant association with analyzed parameters. The co-dominance of MBGFs III, V and VII along with high species diversity of phytoplankton community occurred during the second hydrodynamic instability period which was associated with the reduction in water temperature. It is concluded that the decrease in cyanobacterial species dominance and the general increase in the diversity of phytoplankton community are influenced by pluvial anomaly. The higher water level during the period of pluvial anomaly resulted in nutrient pulse and the mixing of water column in the reservoir, which determined the MBPG phytoplankton community distribution.


ResumoO presente estudo centra-se na estrutura e função da comunidade fitoplanctônica nos períodos de alterações marcantes nas características hidrológicas, influenciado por um evento climático atípico (La Niña) e seu impacto sobre o Reservatório: Armando Ribeiro Gonçalves, no Rio Grande do Norte, situado no bioma Caatinga, localizado na Região Nordeste do Brasil. As principais questões abordadas foram: Quais são os efeitos dos fatores ambientais sobre a variação temporal, baseados no grupo funcional da morfologia (GFBM) da comunidade fitoplanctônica? Como seria a composição das espécies de cianobactérias, em relação a varição das tendências de alta e baixa diversidade do fitoplâncton? As amostras foram coletadas mensalmente durante os anos de 2008-2009 e analisadas em relação a: pH, temperatura, condutividade elétrica, teor de oxigênio dissolvido e os nutrientes, tais como, tais como: nitrato, amônio, nitrogênio total e ortofosfato. As amostras de fitoplâncton foram coletadas para análises quantitativas, bem como, qualitativas para avaliar o índice de riqueza e de diversidade das espécies. Os dados foram divididos em dois períodos diferentes: instabilidade e estabilidade. Os resultados demonstraram alterações significativas no teor de oxigênio dissolvido, transparência da água e nutrientes de nitrogênio, que influenciaram diretamente os GFBM da comunidade do fitoplâncton no espaço e no tempo. A instabilidade da água do reservatório foi causada por fortes chuvas, que exerceu perturbações externas atípicas. Os resultados demonstraram alterações significativas no teor de oxigênio dissolvido, transparência da água e nutrientes de nitrogênio, que influenciaram diretamente os grupos morfofuncionais do fitoplâncton no espaço e no tempo. A instabilidade da água do reservatório foi causada por fortes chuvas, que exerceu perturbações externas atípicas. A sucessão sazonal de GFBM demonstrou a mudança na composição da cianobactéria e sua diversidade, durante os períodos de instabilidade e estabilidade. GFBM VII, composto por cianobactéria colonial com mucilagem esteve associado com baixos valores de condutividade elétrica e alterações no pH. A predominância das espécies filamentosas com heterocistos (GFBM III) ocorreu apenas durante o período de estabilidade hidrodinâmica e sem associação significativa com os parâmetros analisados. A codominância de GFBM III, V e VII juntamente com a elevada diversidade das espécies fitoplanctônicas ocorreram durante o segundo período da estabilidade hidrodinâmica e estiveram associadas com a redução da temperatura da água. Conclui-se que a diminuição da dominância de espécies de cianobactérias e o aumento geral na diversidade da comunidade do fitoplâncton são influenciadas pela anomalia pluvial. O nível da água mais elevado durante o período de anomalia pluvial resultou em um pulso de nutrientes e uma mistura da coluna de água no reservatório, que determinou a distribuição da comunidade fitoplanctônica MBPG.


Subject(s)
Biodiversity , Cyanobacteria/physiology , El Nino-Southern Oscillation , Phytoplankton/physiology , Brazil , Lakes , Seasons
12.
Braz J Biol ; 75(2): 484-90, 2015 May.
Article in English | MEDLINE | ID: mdl-26132036

ABSTRACT

This work presents information regarding the biology and state of conservation of an endangered annual fish Hypsolebias antenori. Fish were captured from small seasonal pools located in Northeastern Brazil. The total body length, body mass, sex ratio, first sexual maturity were investigated. The sampled population showed sexual dimorphism. There was a predominance of females (60%) over males (40%) with a sex ratio of 1: 1.4 and males were bigger and heavier than the females. Amplitude of total length of males ranged from 2.6 to 7.1cm (4.1 ± 1.15) and that of females from 2.2 to 5.4 cm (3.6 ± 0.9). Amplitude of body mass of males varied from 0.25 to 7 g (1.3 g ± 1.4) and that of females from 0.12 to 2.1g (0.7 g ± 0.5). The total weight-length equation of males was Wt = 0.0108Lt3.172 with r = 0.9826 and of females was Wt = 0.0122Lt3.0114 with r = 0.9608. Females attained first sexual maturity at 3.2 cm (± 0.25) total length and males at 3.3 cm (± 0.08) total length. All temporary pools surveyed in Northeastern Brazil were in a high degree of degradation, suffering due to anthropogenic action. Reduced rainfall resulting from global climate change prevents the filling up of these pools, thus preventing the completion of the reproductive cycle of annual fishes. One factor hindering development of conservation strategies is limited literature on biology and conservation status of annual fishes. There is a need for conservation measures to protect annual fish populations, especially creation of protected areas in the Brazilian semiarid region.


Subject(s)
Cyprinodontiformes/classification , Endangered Species , Reproduction , Animals , Brazil , Climate Change , Cyprinodontiformes/anatomy & histology , Female , Male , Sex Ratio
13.
Braz J Biol ; 75(1): 19-29, 2015.
Article in English | MEDLINE | ID: mdl-25945617

ABSTRACT

In lentic freshwater ecosystems, patterns of thermal stratification play a considerable part in determining the population dynamics of phytoplankton. In this study we investigated how these thermal patterns and the associated hydrodynamic processes affect the vertical distribution of phytoplankton during two consecutive diel cycles in a warm polymictic urban reservoir in the metropolitan region of São Paulo, Brazil. Water samples were taken and physical, chemical and biological data collected at half-meter intervals of depth along a water column at a fixed site, every 3 hours throughout the 48-hour period. Two events of stratification, followed by deepening of the thermocline occurred during the study period and led to changes in the vertical distribution of phytoplankton populations. Aphanocapsa delicatissima Nägeli was the single dominant species throughout the 48-hour period. In the second diel cycle, the density gradient induced by temperature differences avoided the sedimentation of Mougeotia sp. C. Agardh to the deepest layers. On the other hand, Pseudanabaena galeata Böcher remained in the 4.0-5.5 m deep layer. The thermal structure of the water was directly affected by two meteorological factors: air temperature and wind speed. Changes in the cell density and vertical distribution of the phytoplankton were controlled by the thermal and hydrodynamic events.


Subject(s)
Environmental Monitoring , Fresh Water , Phytoplankton/physiology , Temperature , Brazil , Phytoplankton/classification , Population Density , Population Dynamics , Seasons
14.
Braz J Biol ; 75(1): 98-103, 2015.
Article in English | MEDLINE | ID: mdl-25945626

ABSTRACT

Dinoflagellates of the genus Ceratium are generally marine organisms, but rare occurrences in freshwater have been observed in Brazil. In this paper we are recording for the first time the presence of Ceratium furcoides, an invasive species, in a shallow, natural intermittent pool formed at a high-altitude at the southern end of the Iron Quadrangle, an iron-mining district of Minas Gerais State (Southeast Brazil). Samples were collected in October and November of 2010 (rainy period). The population density of this organism observed in Lagoa Seca ("Dry Pool") was very low, at most 4 ind L-1. Mountain lakes are extremely vulnerable to atmospheric deposition of organisms, making them valuable witnesses both of the many forms of impact arising from human activities and of the extended global connections that facilitate the dispersion and introduction of new species over great distances. Studies on the population dynamics of C. furcoides in natural tropical systems are still rare and very recent to the brazilian scenario and hence the monitoring of its dynamics and the potential impact on aquatic communities of its becoming established are essential to an understanding of the process of bioinvasion by this species.


Subject(s)
Dinoflagellida/classification , Environmental Monitoring , Introduced Species , Altitude , Brazil , Lakes , Population Density
15.
Braz. j. biol ; 75(2): 484-490, 05/2015. graf
Article in English | LILACS | ID: lil-749686

ABSTRACT

This work presents information regarding the biology and state of conservation of an endangered annual fish Hypsolebias antenori. Fish were captured from small seasonal pools located in Northeastern Brazil. The total body length, body mass, sex ratio, first sexual maturity were investigated. The sampled population showed sexual dimorphism. There was a predominance of females (60%) over males (40%) with a sex ratio of 1: 1.4 and males were bigger and heavier than the females. Amplitude of total length of males ranged from 2.6 to 7.1cm (4.1±1.15) and that of females from 2.2 to 5.4cm (3.6±0.9). Amplitude of body mass of males varied from 0.25 to 7g (1.3g±1.4) and that of females from 0.12 to 2.1g (0.7g±0.5). The total weight-length equation of males was Wt=0.0108Lt3.172 with r = 0.9826 and of females was Wt=0.0122Lt3.0114 with r = 0.9608. Females attained first sexual maturity at 3.2 cm (±0.25) total length and males at 3.3 cm (±0.08) total length. All temporary pools surveyed in Northeastern Brazil were in a high degree of degradation, suffering due to anthropogenic action. Reduced rainfall resulting from global climate change prevents the filling up of these pools, thus preventing the completion of the reproductive cycle of annual fishes. One factor hindering development of conservation strategies is limited literature on biology and conservation status of annual fishes. There is a need for conservation measures to protect annual fish populations, especially creation of protected areas in the Brazilian semiarid region.


Este trabalho apresenta informações sobre a biologia e estado de conservação de Hypsolebias antenori, um peixe anual ameaçado. Os peixes foram capturados em pequenas poças temporárias localizadas no Nordeste do Brasil. O comprimento total, peso total, proporção sexual e a primeira maturação sexual foram investigados. A espécie em estudo apresentou dimorfismo sexual bem evidente. Houve um predomínio de fêmeas (60%) sobre os machos (40%), com uma razão sexual de 1M: 1,4F. Os machos foram significativamente maiores e mais pesados do que as fêmeas. A amplitude do comprimento total dos machos variou de 2,6 a 7,1 centímetros (4,1 ± 1,15) e as fêmeas de 2,2 a 5,4 centímetros (3,6 ± 0,9). A amplitude de peso dos machos variou de 0,25 a 7 g (1,4 ± 1,3 g), enquanto que as fêmeas de 0,12 a 2,1 g (0,5 ± 0,7 g). A equação da relação peso total/comprimento dos machos foi Wt = 0.0108Lt3.172 com r = 0,9826 e para fêmeas foi Wt = 0.0122Lt3.0114 com r = 0,9608. As fêmeas alcançaram a primeira maturação sexual com 3,2 cm ( ± 0,25) de comprimento total e os machos com 3,3 centímetros ( ± 0,08 ) de comprimento total. Todas as poças temporárias amostradas neste trabalho estavam em um alto grau de degradação, principalmente devido à ação antrópica. Observamos que diminuição das chuvas e a desertificação decorrente das mudanças climáticas globais que também são alarmantes e poderão impedir a conclusão do ciclo reprodutivo dos peixes anuais. As informações sobre a biologia e o estado de conservação dos peixes anuais ainda são limitadas, portanto há uma grande necessidade estudos e de medidas de conservação para proteger as populações de peixes anuais, entre elas especialmente a criação de áreas proteção nos ambientes aquáticos efêmeros do semiárido brasileiro.


Subject(s)
Animals , Female , Male , Cyprinodontiformes/classification , Endangered Species , Reproduction , Brazil , Climate Change , Cyprinodontiformes/anatomy & histology , Sex Ratio
16.
Braz. j. biol ; 75(1): 19-29, Jan-Mar/2015. tab, graf
Article in English | LILACS | ID: lil-744332

ABSTRACT

In lentic freshwater ecosystems, patterns of thermal stratification play a considerable part in determining the population dynamics of phytoplankton. In this study we investigated how these thermal patterns and the associated hydrodynamic processes affect the vertical distribution of phytoplankton during two consecutive diel cycles in a warm polymictic urban reservoir in the metropolitan region of São Paulo, Brazil. Water samples were taken and physical, chemical and biological data collected at half-meter intervals of depth along a water column at a fixed site, every 3 hours throughout the 48-hour period. Two events of stratification, followed by deepening of the thermocline occurred during the study period and led to changes in the vertical distribution of phytoplankton populations. Aphanocapsa delicatissima Nägeli was the single dominant species throughout the 48-hour period. In the second diel cycle, the density gradient induced by temperature differences avoided the sedimentation of Mougeotia sp. C. Agardh to the deepest layers. On the other hand, Pseudanabaena galeata Böcher remained in the 4.0-5.5 m deep layer. The thermal structure of the water was directly affected by two meteorological factors: air temperature and wind speed. Changes in the cell density and vertical distribution of the phytoplankton were controlled by the thermal and hydrodynamic events.


Em ecossistemas de água doce, os padrões de estratificação térmica têm uma influência considerável sobre a dinâmica populacional do fitoplâncton. Neste estudo nós investigamos como os padrões de estratificação térmica e os processos hidrodinâmicos afetaram a distribuição vertical do fitoplâncton durante dois ciclos nictemerais consecutivos em um reservatório urbano na cidade de São Paulo. As amostragens e medidas das variáveis físicas e químicas foram realizadas a cada três horas durante um período de 48 horas, ao longo de um perfil vertical. Ocorreram dois eventos de estratificação e subsequente abaixamento da termoclina acarretando alterações na distribuição vertical do fitoplâncton. Aphanocapsa delicatissima Nägeli foi a principal espécie dominante durante todo o período avaliado. No segundo ciclo nictemeral o gradiente de densidade criado pelas diferenças de temperatura impediu o afundamento de Mougeotia sp. C. Agardh para as camadas mais profundas. Por outro lado Pseudoanabaena galeata Böcher se manteve nas camadas de 4.0 e 5.5 m. A estrutura térmica da água foi diretamente afetada pelos fatores meteorológicos temperatura do ar e velocidade do vento. As mudanças na densidade e na distribuição vertical do fitoplâncton foram controladas pelos eventos térmicos e hidrodinâmicos.


Subject(s)
Environmental Monitoring , Fresh Water , Phytoplankton/physiology , Temperature , Brazil , Population Density , Population Dynamics , Phytoplankton/classification , Seasons
17.
Braz. j. biol ; 75(1): 98-103, Jan-Mar/2015. graf
Article in English | LILACS | ID: lil-744346

ABSTRACT

Dinoflagellates of the genus Ceratium are generally marine organisms, but rare occurrences in freshwater have been observed in Brazil. In this paper we are recording for the first time the presence of Ceratium furcoides, an invasive species, in a shallow, natural intermittent pool formed at a high-altitude at the southern end of the Iron Quadrangle, an iron-mining district of Minas Gerais State (Southeast Brazil). Samples were collected in October and November of 2010 (rainy period). The population density of this organism observed in Lagoa Seca (“Dry Pool”) was very low, at most 4 ind L–1. Mountain lakes are extremely vulnerable to atmospheric deposition of organisms, making them valuable witnesses both of the many forms of impact arising from human activities and of the extended global connections that facilitate the dispersion and introduction of new species over great distances. Studies on the population dynamics of C. furcoides in natural tropical systems are still rare and very recent to the brazilian scenario and hence the monitoring of its dynamics and the potential impact on aquatic communities of its becoming established are essential to an understanding of the process of bioinvasion by this species.


Dinoflagelados do gênero Ceratium são principalmente marinhos, porém existem raras ocorrências em água doce no Brasil. Neste estudo registramos pela primeira vez a ocorrência de Ceratium furcoides, uma espécie invasora em um lago altitudinal natural raso localizado na porção sul do Quadrilátero Ferrífero, uma área de extração mineral no estado de Minas Gerais. As coletas foram realizadas nos meses de outubro e novembro de 2010 (período chuvoso). As densidades observadas para C. furcoides na Lagoa Seca foram muito baixas, com máximo de 4 ind L–1. Lagos de altitude são altamente vulneráveis à deposição atmosférica, o que os torna importantes testemunhos não só dos múltiplos impactos derivados de atividades humanas, mas também das extensas conexões globais, que acabam por facilitar a dispersão e introdução de espécies. Estudos sobre a dinâmica de C. furcoides em sistemas tropicais naturais ainda são escassos e por isso, o monitoramento de sua dinâmica e dos impactos potenciais em comunidades aquáticas a partir do seu estabelecimento, torna-se fundamental para o entendimento dos processos relacionados à bioinvasão desta espécie.


Subject(s)
Dinoflagellida/classification , Environmental Monitoring , Introduced Species , Altitude , Brazil , Lakes , Population Density
18.
Braz J Biol ; 74(2): 483-8, 2014 May.
Article in English | MEDLINE | ID: mdl-25166335

ABSTRACT

Annelid worms represent a significant part of freshwater benthic communities worldwide and Oligochaeta is a particularly species-rich group. Dero (A) bimagnasetus (Naididae) previously found and described from a small marsh in Surinam in 1974, has now been found for the first time in Barra Lake, MG, Brazil. Due to the scarce biological data and absence of ecological information in the literature regarding this species we are presenting morphological information on the specimens obtained and the physical and chemical characteristics of the habitat they were found. This species occurred only in the littoral zone of Barra Lake, in muddy, low oxygen, low conductivity and low organic matter sediment. The four individuals collected ranged 3.17-4.15 mm total length; 0.25 - 0.26 mm body width and 0.16-0.21 mm3 total volume. Considering the present anthropic pressures on freshwater biota and fast biodiversity losses worldwide it is now recognized that attention must be paid to low abundance species and the urgency for preservation of their habitats.


Subject(s)
Ecosystem , Oligochaeta/anatomy & histology , Oligochaeta/classification , Animals , Biodiversity , Brazil , Environmental Monitoring , Lakes , Seasons
19.
Braz. j. biol ; 74(2): 483-488, 5/2014. tab, graf
Article in English | LILACS | ID: lil-719227

ABSTRACT

Annelid worms represent a significant part of freshwater benthic communities worldwide and Oligochaeta is a particularly species-rich group. Dero (A) bimagnasetus (Naididae) previously found and described from a small marsh in Surinam in 1974, has now been found for the first time in Barra Lake, MG, Brazil. Due to the scarce biological data and absence of ecological information in the literature regarding this species we are presenting morphological information on the specimens obtained and the physical and chemical characteristics of the habitat they were found. This species occurred only in the littoral zone of Barra Lake, in muddy, low oxygen, low conductivity and low organic matter sediment. The four individuals collected ranged 3.17-4.15 mm total length; 0.25 - 0.26 mm body width and 0.16-0.21 mm3 total volume. Considering the present anthropic pressures on freshwater biota and fast biodiversity losses worldwide it is now recognized that attention must be paid to low abundance species and the urgency for preservation of their habitats.


Vermes anelídeos representam uma parte significativa das comunidades de água doce em todo o mundo e Oligochaeta é um grupo particularmente rico em espécies. Dero (A) bimagnasetus (Naididae) havia sido encontrado e descrito em um pequeno pântano no Suriname em 1974, e agora também coletado na lagoa Barra, MG, Brasil. Devido ao baixo número de espécimes coletados e à ausência de informações ecológicas sobre esta espécie, estamos apresentando informações sobre a morfometria dos espécimes obtidos e as características físicas e químicas de seu habitat. Esta espécie ocorreu apenas na região litorânea da lagoa da Barra, em sedimento lamacento e com pouca matéria orgânica, baixa concentração de oxigênio e baixa condutividade elétrica na água. Os quatro indivíduos encontrados tiveram 3,17-4,15 mm de comprimento total; 0,25-0,26 mm de largura e 0,16-0,21 mm3 de biovolume. Considerando as atuais pressões antrópicas sobre a biota de água doce e as rápidas perdas de biodiversidade em todo o mundo, é agora reconhecido que muita atenção deve ser dada às espécies pouco abundantes e que é urgentemente necessário preservar seus habitats.


Subject(s)
Animals , Ecosystem , Oligochaeta/anatomy & histology , Oligochaeta/classification , Biodiversity , Brazil , Environmental Monitoring , Lakes , Seasons
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