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1.
J Fish Biol ; 89(1): 315-36, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27278087

RESUMO

The Patos Lagoon basin is a large (201 626 km(2) ) and complex drainage system in southern Brazil. The lagoon is 250 km long and 60 km wide, covering an area of 10 360 km(2) . The exchange of water with the Atlantic Ocean occurs through a 0·8 km wide and 15 m deep inlet, fixed by 4 km long jetties, at the southernmost part of the Patos Lagoon. The estuarine area is restricted to its southern portion (10%), although the upper limit of saline waters migrates seasonally and year to year, influenced by the wind regime and river discharge. The known number of recorded limnetic fish species is 200, but this number is expected to increase. A higher endemism is observed in fish species occurring in upper tributaries. The basin suffers from the direct impact of almost 7 million inhabitants, concentrated in small to large cities, most with untreated domestic effluents. There are at least 16 non-native species recorded in natural habitats of the Patos Lagoon basin, about half of these being from other South American river basins. Concerning the fishery, although sport and commercial fisheries are widespread throughout the Patos Lagoon basin, the lagoon itself and the estuarine area are the main fishing areas. Landing statistics are not available on a regular basis or for the whole basin. The fishery in the northern Patos Lagoon captures 31 different species, nine of which are responsible for most of the commercial catches, but only three species are actually sustaining the artisanal fishery: the viola Loricariichthys anus: 455 kg per 10 000 m(2) gillnet per day, the mullet Mugil liza: 123 kg per 10 000 m(2) gillnet per day and the marine catfish Genidens barbus: 50 kg per 10 000 m(2) gillnet per day. A decline of the fish stocks can be attributed to inadequate fishery surveillance, which leads to overfishing and mortality of juveniles, or to decreasing water quality because of urban and industrial activities and power production. Global climatic changes also represent a major threat to the Patos system by changing the frequency of El Niño-La Niña-Southern Oscillation (ENSO).


Assuntos
Conservação dos Recursos Naturais , Peixes , Animais , Oceano Atlântico , Brasil , Ecossistema , El Niño Oscilação Sul , Pesqueiros , Espécies Introduzidas , Rios , Smegmamorpha
2.
J Fish Dis ; 37(9): 771-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23952070

RESUMO

Infections with the parasitic flagellate Ichthyobodo necator (Henneguy, 1883) cause severe skin and gill disease in rainbow trout Oncorhynchus mykiss (Walbaum, 1792) juveniles. The epidermal disturbances including hyperplasia and mucous cell exhaustion caused by parasitization are known, but no details on specific cellular and humoral reactions have been presented. By applying gene expression methods and immunohistochemical techniques, further details of immune processes in the affected skin can be presented. A population of I. necator was established in the laboratory and used to induce an experimental infection of juvenile rainbow trout. The course of infection was followed by sampling for parasite enumeration, immunohistochemistry (IHC) and quantitative PCR (qPCR) on days 0, 5, 9 and 14 post-infection. IHC showed a significant increase in the occurrence of IgM-positive cells in the skin of the infected fish, whereas IgT-positive cells were eliminated and the number of CD8-positive cells declined. qPCR studies supported the IHC findings showing a significant increase in IgM and a decrease in the CD8 gene expression. In addition, genes encoding innate immune genes such as lysozyme, SAA and cathelicidin 2 were up-regulated. Expression of cytokines (IL-1ß, IL-4/13A, IL-6, IL-8, IL-10), the cell marker CD4 and the transcription factor GATA3 showed a significant increase after infection. Cytokine profiling including up-regulation of IL-4/13A and IL-10 genes and transcription factor GATA3 connected to the proliferation of IgM producing lymphocytes suggests a partial shift towards a Th2 response associated with the I. necator infection.


Assuntos
Citocinas/genética , Infecções por Euglenozoa/veterinária , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica , Kinetoplastida/fisiologia , Oncorhynchus mykiss , Animais , Linfócitos T CD8-Positivos , Citocinas/metabolismo , Epiderme/imunologia , Epiderme/parasitologia , Infecções por Euglenozoa/genética , Infecções por Euglenozoa/imunologia , Infecções por Euglenozoa/parasitologia , Doenças dos Peixes/genética , Doenças dos Peixes/parasitologia , Imunoglobulina M/genética , Imunoglobulina M/metabolismo , Imuno-Histoquímica/veterinária , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária
3.
Phys Rev Lett ; 111(17): 172501, 2013 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-24206482

RESUMO

The nucleus (154)Gd is located in a region of the nuclear chart where rapid changes of nuclear deformation occur as a function of particle number. It was investigated using a combination of γ-ray scattering experiments and a γγ-coincidence study following electron capture decay of (154)Tb(m). A novel decay channel from the scissors mode to the first excited 0(+) state was observed. Its transition strength was determined to B(M1;1(sc)(+)→0(2)(+))=0.031(4)µ(N)(2). The properties of the scissors mode of (154)Gd imply a much larger matrix element than previously thought for the neutrinoless double-ß decay to the 0(2)(+) state in such a shape-transitional region. Theory indicates an even larger effect for (150)Nd.

4.
Sci Total Environ ; 801: 149664, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34418619

RESUMO

The palaeolimnological conditions of Mirim Lagoon, a large coastal shallow lagoon under the influence of historical human impacts related to the development of the primary sector of the economy were reconstructed. The first significant human impact consisted of locking the estuarine system to induce the transition from brackish to freshwater conditions. During this transition, the sedimentation rate consistently increased from pre-disturbance values of 0.25 cm yr-1 to >1 cm yr-1. A concomitant increase in nitrogen and carbon values was recorded indicating a related eutrophication process. The highest nutrient levels were achieved during the 1990s after the incorporation of cutting-edge technologies for agricultural production such as high-yielding varieties of rice resistant to climate variability and pests, and the use of inorganic fertilisers, pesticides and water supply controlled by irrigation. After 2011, the soybean production boosted and the area cultivated with this oilseed equalled the area of rice paddies, i.e., 2 × 105 ha. A sharp decrease in δ13C from -19 to -24‰ and in δ15N from 6 to 2‰ were observed in the sedimentary record, indicating a major shift in the composition of the organic matter after the agricultural intensification. Trace elements Cr, Cu, Ni and Zn showed a high positive correlation with Al and Fe, and enrichment factors near 1, indicating a natural and terrigenous source of these elements and also unpolluted conditions. However, the increase of As after 1990 and the positive correlation with Pb was associated with agricultural practices. All elemental ratios (K/Al, Ti/Al and V/Cr) showed constant pre-disturbance trends and a turning point ca. the 1990s. Microplastics were detected from the beginning of the 1990s and increased towards recent sediments, thus corroborating an anthropogenically impacted scenario. Therefore, the development of the primary sector of the economy exerted clear impacts on the environmental quality of the system.


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Monitoramento Ambiental , Eutrofização , Sedimentos Geológicos , Humanos , Metais Pesados/análise , Plásticos , Oligoelementos/análise , Água , Poluentes Químicos da Água/análise
5.
J Neuroendocrinol ; 2(6): 803-6, 1990 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19215422

RESUMO

Abstract Autoregulation of receptor systems by their own ligands is a well established biological phenomenon. While down-regulation of the glucocorticoid binding capacity by glucocorticoids has been shown in animals and humans, data on up-regulation processes in humans are lacking. To further explore glucocorticoid receptor plasticity in relation to endogenous ligands, glucocorticoid binding parameters were assessed in 15 healthy controls before and after oral administration of 1.5 g metyrapone with and without dexamethasone pretreatment. Administration of metyrapone resulted in blockade of the feedback of the hypothalamic-pituitary-adrenal system as shown by the rise in adrenocorticotropin levels, while pretreatment with 1 mg dexamethasone completely suppressed adrenocorticotropin concentrations. Glucocorticoid binding sites per lymphocyte exhibited an increase of 63% following metyrapone administration, which was prevented by dexamethasone pretreatment. Comparison of morning and afternoon glucocorticoid binding sites per cell in 11 healthy volunteers further revealed a diurnal rhythm of glucocorticoid receptor sites. These data suggest that human lymphocyte glucocorticoid receptors are under autoregulatory control.

13.
Arthropod Struct Dev ; 37(4): 333-46, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18394959

RESUMO

The fish ectoparasites Branchiura (Crustacea) display two different ways of attachment to the fish surface as adults: the first maxillae are either hooks (Dolops) or suction discs (Argulus, Chonopeltis, and Dipteropeltis). In larval Argulus foliaceus the first maxillae are hooks. With the first molecular phylogeny of the Branchiura as a background, the present paper discusses the evolutionary scenarios leading to hooks versus suction discs. Specific homologies exist between larval Argulus foliaceus hooks and adult Dolops ranarum hooks. These include the presence of a comparable number of segments/portions and a distal segment terminating in a double structure: a distal two-part hook (in Argulus) or one hook and an associate spine-like structure (in Dolops). In the phylogenetic reconstruction based on three molecular markers (mitochondrial 16S rRNA, nuclear 18S and 28S rRNA), Dolops ranarum is found to be in a sister group position to all other Branchiura, which in this analysis include six Argulus and one Chonopeltis sequences. Based on the molecular phylogeny a likely evolutionary scenario is that the ancestral branchiuran used hooks (on the first maxilla) for attachment, as seen in Dolops, of which the proximal part was subsequently modified into suction discs in Argulus and Chonopeltis (and Dipteropeltis). The sister group relationship of the Branchiura and Pentastomida is confirmed based on the most comprehensive taxon sampling until now. No evidence was found for a branchiuran in-group position of the Pentastomida.


Assuntos
Crustáceos/ultraestrutura , Evolução Molecular , Filogenia , Animais , Crustáceos/genética , Crustáceos/crescimento & desenvolvimento , Genes Mitocondriais , Larva/anatomia & histologia , Larva/genética , RNA Ribossômico/genética
14.
Phys Rev Lett ; 96(5): 052501, 2006 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-16486924

RESUMO

Exited states in 134Pr were populated in the fusion-evaporation reaction 119Sn(19F,4n)134Pr. Recoil distance Doppler-shift and Doppler-shift attenuation measurements using the Euroball spectrometer, in conjunction with the inner Bismuth Germanate ball and the Cologne plunger, were performed at beam energies of 87 MeV and 83 MeV, respectively. Reduced transition probabilities in 134Pr are compared to the predictions of the two quasiparticle + triaxial rotor and interacting boson fermion-fermion models. The experimental results do not support the presence of static chirality in 134Pr underlying the importance of shape fluctuations. Only within a dynamical context the presence of intrinsic chirality in 134Pr can be supported.

15.
Phys Rev Lett ; 97(6): 062501, 2006 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-17026165

RESUMO

Lifetimes of prolate intruder states in 186Pb and oblate intruder states in 194Po have been determined by employing, for the first time, the recoil-decay tagging technique in recoil distance Doppler-shift lifetime measurements. In addition, lifetime measurements of prolate states in 188Pb up to the 8+ state were carried out using the recoil-gating method. The B(E2) values have been deduced from which deformation parameters |beta2|=0.29(5) and |beta2|=0.17(3) for the prolate and the oblate bands, respectively, have been extracted. The results also shed new light on the mixing between different shapes.

16.
Cell Tissue Res ; 212(1): 17-28, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6254659

RESUMO

Cysteine-sensitive alkaline phosphatase and/or ouabain-sensitive Na+, K+ -ATPase were studied by ultrastructure cytochemistry in epithelial cells of proximal and distal kidney tubules. Alkaline phosphatase reactivity was confined to the surface of the microvillous luminal cell membrane of proximal tubule cells, whereas distal tubules and collecting ducts were unreactive. The Na+, K+- ATPase reactivity was localized evenly along the cytoplasmic side of the basolateral cell membrane of cells of proximal and distal tubules and in collecting ducts. In the proximal tubules, where the activity was strongest, the Na+, K+- ATPase deposits were also found in the 10--50 nm gap between the cell membrane and the cisternae of tubulo-cisternal endoplasmic reticulum (TER) underlying a major part of the basolateral cell membrane. The restriction of NA+, K+ -ATPase sites, which are involved in extrusion of Na+ from the cell, to a narrow cytoplasmic compartment located between the cell membrane and the cisternae of TER, is consistent with a transport role for the TER.


Assuntos
Túbulos Renais Distais/enzimologia , Túbulos Renais Proximais/enzimologia , Túbulos Renais/enzimologia , ATPase Trocadora de Sódio-Potássio/análise , Animais , Membrana Celular/enzimologia , Retículo Endoplasmático/ultraestrutura , Túbulos Renais Coletores/enzimologia , Túbulos Renais Distais/ultraestrutura , Túbulos Renais Proximais/ultraestrutura , Microvilosidades/enzimologia , Coelhos
17.
Nord Vet Med ; 38(2): 80-4, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3725584

RESUMO

The clinical features of a case of granulosa cell tumour in the blue fox (Alopex lagopus) are described. The associated hormonal changes are discussed in relation to present knowledge of the regulation of the oestrous and furring cycles in this species.


Assuntos
Endométrio/patologia , Raposas , Tumor de Células da Granulosa/veterinária , Neoplasias Ovarianas/veterinária , Animais , Feminino , Tumor de Células da Granulosa/complicações , Tumor de Células da Granulosa/patologia , Hiperplasia/veterinária , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/patologia
18.
Cell Tissue Res ; 228(1): 13-20, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6831521

RESUMO

Rat livers were fixed by perfusion with glutaraldehyde via the portal vein and postfixed with a mixture of osmium tetroxide and potassium ferricyanide. Subsurface cisterns and vesicles were demonstrated, and, from serial sections, it appears that these organelles are part of large, fenestrated cisterns situated parallel to and at a distance of 20-40 nm from the lateral plasma membrane. Some of the cisterns possessed ribosomes on the surface facing the interior of the cell and, at points, they were continuous with the endoplasmic reticulum. From the lateral cisterns, tubules approached the plasma membrane facing the space of Disse and the sinusoid. A network of tubules was found in the vicinity of the bile canaliculus; a part of it lay close to the canalicular plasma membrane. Serial sectioning revealed that this network was continuous with the lateral cisterns via the endoplasmic reticulum. This morphology resembles that of tubulo-cisternal endoplasmic reticulum of such transporting epithelia as the choroid plexus and the renal proximal tubules.


Assuntos
Retículo Endoplasmático/ultraestrutura , Fígado/ultraestrutura , Animais , Retículo Endoplasmático/fisiologia , Masculino , Ratos , Ratos Endogâmicos
19.
Acta Paediatr ; 91(11): 1174-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12463314

RESUMO

AIM: Pneumonia in childhood may be associated with surfactant dysfunction and severe acute respiratory distress syndrome (ARDS). The aim of this study was to investigate the effects of surfactant treatment on oxygenation in 8 infants (age range: 1 mo to 13 y) with severe respiratory failure owing to viral, bacterial or Pneumocystis Carinii pneumonia. METHODS AND RESULTS: Instillation of a modified porcine surfactant (Curosurf) improved gas exchange immediately. Median paO2/FiO2 increased from 66 to 140 mmHg (8.8-18.7 kPa; p < 0.01) within 1 h of surfactant treatment. Seven of the 8 patients received multiple surfactant doses. Four patients (50%) died 3-62 d after surfactant treatment. However, 6 patients (75%) were immunodeficient, so that the observed mortality rate was mainly due to the underlying disease. CONCLUSION: Surfactant dysfunction probably plays a role in the pathophysiology of severe paediatric ARDS triggered by pneumonia, as it was found that surfactant instillation rapidly improved gas exchange in the majority of the affected infants in our study. Larger randomized controlled studies are necessary to evaluate the effects of surfactant treatment on morbidity and mortality.


Assuntos
Produtos Biológicos , Fosfolipídeos , Troca Gasosa Pulmonar , Surfactantes Pulmonares/uso terapêutico , Síndrome do Desconforto Respiratório do Recém-Nascido/tratamento farmacológico , Síndrome do Desconforto Respiratório do Recém-Nascido/fisiopatologia , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/fisiopatologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
20.
Int J Oral Surg ; 14(3): 229-34, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3926666

RESUMO

A stereophotographic method for volumetric determination of the extraoral swelling after mandibular third molar removal is developed. The method error was 1.0 cm3. Compared to the size of the maximal swelling after removal of impacted wisdom teeth, this error is considerable. The technique can, however, be improved and furthermore applied to measurements of volume changes in other cranio-facial areas, as well as in other parts of the body.


Assuntos
Edema/patologia , Doenças da Boca/patologia , Bochecha , Edema/etiologia , Humanos , Manequins , Dente Serotino/cirurgia , Doenças da Boca/etiologia , Fotogrametria/métodos , Extração Dentária/efeitos adversos
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