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2.
Gen Comp Endocrinol ; 249: 32-39, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28263819

RESUMO

Exposure to high environmental ammonia (HEA) levels increases the vulnerability of fishes to parasitic, viral and bacterial diseases. We tested the hypothesis that elevated plasma cortisol levels play a role in the HEA-mediated immunosuppression in fishes. To this end, we tested the effect of exogenous cortisol treatment on the lipopolysaccharide (LPS)-induced immune response in zebrafish (Danio rerio). Also, to test whether glucocorticoid receptor (GR) signaling is involved in HEA-mediated immunosuppression, zebrafish were treated with mifepristone, a GR antagonist, and the LPS-induced immune response assessed after HEA exposure. We evaluated a panel of important immunity-related genes including interleukin 1ß (il1b) and suppressor of cytokine signaling (socs-1a, 2, 3) and acute phase response genes [serum amyloid A (saa), transferrin (tfa), leukocyte cell-derived chemotaxin 2-like (lect2l), haptoglobin (hp), hepcidin (=hepatic anti-microbial peptide hamp), and complement component 3b (c3b)] by real-time quantitative PCR. Our results demonstrate that exogenous cortisol administration as well as elevated cortisol levels in response to HEA exposure modulate mRNA transcript levels of key mediators of the innate immune response in zebrafish. Mifepristone treatment reduced whole body cortisol levels and eliminated the HEA-mediated changes in transcript abundance of socs1a, il1b, as well as APR genes. Together, these results suggest that the HEA effect on the innate immune response is in part mediated by cortisol signaling, while the mode of action, including the receptors involved remains to be elucidated.


Assuntos
Altitude , Amônia/efeitos adversos , Meio Ambiente , Hidrocortisona/metabolismo , Imunidade , Peixe-Zebra/imunologia , Proteínas de Fase Aguda/metabolismo , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Imunidade/efeitos dos fármacos , Imunidade/genética , Lipopolissacarídeos/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
3.
Int J Dent Hyg ; 14(3): 202-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25727335

RESUMO

AIM: The aims of this study were to compare the volatile sulphur compounds (VSC)-reducing effect of two commercial mouthrinses using a morning bad breath model and to assess the role of mechanical plaque control (MPC) when performed previously to mouthrinse use. PATIENTS AND METHODS: Eleven volunteers with good oral health were enrolled in a double-blind, randomized, six-step crossover design study with a 7-day washout period. Two commercial mouthrinses were tested using a saline solution (NaCl 0.9%) as a negative control: one mouthrinse contained 0.05% chlorhexidine, 0.05% cetylpyridinium chloride and 0.14% zinc lactate (CHX-CPC-Zn), while the other contained 0.05% chlorhexidine, 0.15% triclosan and 0.18% zinc pidolate (CHX-triclosan-Zn). A portable sulphide monitor (Halimeter(®) ) was used for VSC quantification. Measurements were made at baseline, and 1, 3 and 5 h after rinsing. Significant differences were detected by analysis of variance. RESULTS: No significant differences between groups were detected at baseline. We were unable to demonstrate a significant influence of mechanical plaque control on the reduction of VSC levels when performed before mouthrinse use (P = 0.631). Both mouthrinses effectively lowered VSC levels in all test intervals (P < 0.05). No statistically significant differences were found between mouthrinses in any of the test intervals (P = 0.629, 0.069 and 0.598 at 1, 3 and 5 h). CONCLUSION: This study demonstrated that CHX-CPC-Zn and CHX-triclosan-Zn have significant and similar effects in reducing VSC levels, which persist for at least 5 h. Such effects were independent of previous MPC, which failed to improve on the results of mouthrinse use alone.


Assuntos
Clorexidina/uso terapêutico , Halitose/tratamento farmacológico , Antissépticos Bucais/uso terapêutico , Compostos de Enxofre/química , Triclosan/uso terapêutico , Zinco/uso terapêutico , Adulto , Cetilpiridínio/uso terapêutico , Estudos Cross-Over , Placa Dentária/tratamento farmacológico , Método Duplo-Cego , Feminino , Halitose/induzido quimicamente , Voluntários Saudáveis , Humanos , Masculino , Análise Multivariada , Cloreto de Sódio/uso terapêutico , Sulfetos/análise , Fatores de Tempo
4.
Comp Biochem Physiol A Mol Integr Physiol ; 163(3-4): 272-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22903054

RESUMO

The reproductive cycle in teleosts is timed to guarantee that eggs hatch in the right place at the right time, with environmental factors playing important roles in entraining and controlling the entire process. The effects of some environmental factors, like temperature and photoperiod, are now well understood. There are only a few studies regarding the effects of hydrostatic pressure (HP) on the reproductive cycle, in spite of its importance as a ubiquitous factor in all biological environments and affecting all living organisms. Hydrostatic pressure is of particular importance in fish because they can also experience rapid and cyclic changes in HP due to vertical movements in the water column. The aim of the present research was to investigate the effects of vertical migrations on the reproductive steroids of maturing female flounder. After a 14 day exposure to cyclic hydrostatic pressure (with a period of 12.4h and with a maximum peak of 800 kPa of absolute hydrostatic pressure), fish showed significantly lower plasmatic concentrations of "5ß,3α" steroids, metabolites of the putative maturation-inducing steroid in flounder (17α,20ß-dihydroxy-4-pregnen-3-one). Results indicate that environmentally realistic cyclic changes of hydrostatic pressure can influence the metabolism of reproductive steroids. This suggests a physiological role of tidally-associated vertical migrations, affecting oocyte maturation and retarding the reproductive cycle in this species until the spawning ground is attained.


Assuntos
Estradiol/sangue , Linguado/fisiologia , Testosterona/sangue , Animais , Feminino , Linguado/sangue , Pressão Hidrostática , Hidroxiprogesteronas/sangue , Hidroxiprogesteronas/urina , Ovário/citologia , Ovário/fisiologia , Progestinas/sangue , Vitelogênese
5.
Braz J Biol ; 82: e242596, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133566

RESUMO

Hops is a new culture in Brazil. Tissue culture can be an important technique for rapid hop propagation. This paper aims to characterize responses from different genotypes under different growth regulators through the interrelationship of response variables important to hop in vitro growth. Three genotypes were cultivated in six culture media with different combinations of growth regulators, BAP (6-benzylaminopurine), IAA (3-indolacetic acid) and GA3 (gibberellic acid). The means were compared by orthogonal contrasts and the interrelationship of the response variables was performed by path analysis. American genotypes showed favorable root development under the BAP + IAA combination, while the use of IAA improved shoot development. The origin of genotypes was important for defining the best protocol for in vitro cultivation. The path coefficient showed that the variable number of shoots has stronger direct effect on the number of nodal segments. Additionally, in tissue culture assays, the use of a covariable and proper error distribution significantly increased experimental accuracy.


Assuntos
Reguladores de Crescimento de Plantas , Brasil , Meios de Cultura , Genótipo , Brotos de Planta/genética
6.
J Fish Biol ; 77(1): 279-84, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20646152

RESUMO

Hydrostatic pressure elevated to 500 kPa for 14 days was found to affect hepatic 7-ethoxyresorufin-O-deethylase (EROD), oxidized protein (POx), protein yield and branchial Na(+)-K(+)-ATPase. No effect on glutathione-S-transferase (GST), superoxidase dismutase (SOD), catalase (CAT), lipid peroxidation (LP), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), condition factor (K) and hepato-somatic index (I(H)) was encountered.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Proteínas de Peixes/metabolismo , Pressão/efeitos adversos , Dourada/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Biomarcadores/metabolismo , Peroxidação de Lipídeos , Fígado/metabolismo , Poluição da Água/efeitos adversos
7.
Sci Total Environ ; 627: 1505-1514, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30857112

RESUMO

The growing economic interest in the exploitation of mineral resources on deep-ocean beds, including those in the vicinity of sensitive-rich habitats such as hydrothermal vents, raise a mounting concern about the damage that such actions might originate to these poorly-know ecosystems, which represent millions of years of evolution and adaptations to extreme environmental conditions. It has been suggested that mining may cause a major impact on vent ecosystems and other deep-sea areas. Yet, the scale and the nature of such impacts are unknown at present. Hence, building upon currently available scientific information it is crucial to develop new cost-effective technologies embedded into rigorous operating frameworks. The forward-thinking provided here will assist in the development of new technologies and tools to address the major challenges associated with deep sea-mining; technologies for in situ and ex situ observation and data acquisition, biogeochemical processes, hazard assessment of deep-sea mining to marine organisms and development of modeling tools in support of risk assessment scenarios. These technological developments are vital to validate a responsible and sustainable exploitation of the deep-sea mineral resources, based on the precautionary principle.

8.
Rev Neurol ; 65(1): 13-18, 2017 Jul 01.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-28650062

RESUMO

INTRODUCTION: Cancer patients have increased stroke risk from direct and indirect malignancy effects. Intravenous thrombolysis with recombinant tissue plasminogen activator (rtPA) is standard medical treatment for acute ischemic stroke (AIS). AIM: To review rtPA use in AIS patients with active cancer. SUBJECTS AND METHODS: Retrospective observational case-control study evaluating patients with AIS and cancer admitted to our stroke unit between January/2010 and June/2015. RESULTS: Seven cases were identified (86% male; median age: 76), and 20 controls were included matched for age and Oxfordshire Community Stroke Project classification. 29% experienced direct procedure complications vs 30% within the control group, 14% suffered haemorrhagic transformation (vs 20%), one patient experienced serious systemic haemorrhage (case) and one patient experienced serious intracerebral haemorrhage (control). After three months' follow-up, 43% were independent compared with 25% controls, and 29% had died (vs 30%). Undetermined aetiology subtype (TOAST classification) was more frequent in cancer patients when compared to controls (71% vs 20%). CONCLUSION: Severe haemorrhagic complications, potentiated by rtPA, carry increased risk of morbidity and mortality. Nevertheless, selected cancer patients with AIS may benefit from rtPA treatment. Active cancer should not be considered an absolute contraindication to rtPA use. Risk of complications and life expectancy should be assessed when making this decision.


TITLE: Seguridad y efectividad del rtPA en el ictus isquemico agudo en pacientes con cancer activo: estudio de casos y controles.Introduccion. Los pacientes con cancer tiene un mayor riesgo de ictus debido a los efectos malignos directos e indirectos. La trombolisis intravenosa con activador tisular del plasminogeno recombinante (rtPA) constituye un tratamiento medico estandar para el ictus isquemico agudo. Objetivo. Revisar el uso de rtPA en el ictus isquemico agudo en pacientes con cancer activo. Sujetos y metodos. Estudio retrospectivo observacional de casos y controles para evaluar pacientes con ictus isquemico agudo y cancer admitidos en la unidad de ictus entre enero de 2010 y junio de 2015. Resultados. Se identificaron siete casos (86% varones; mediana de edad: 76 años) y tambien se incluyeron 20 controles pareados por edad y clasificacion del Oxfordshire Community Stroke Project. Un 29% de casos experimento complicaciones directas del procedimiento frente a un 30% en el grupo control. Un 14% sufrio transformacion hemorragica (frente a un 20%). Un paciente (caso) sufrio una hemorragia sistemica grave, y otro (control), una hemorragia intracerebral grave. A los tres meses, un 43% era independiente (frente a un 25% de los controles) y un 29% habia fallecido (frente a un 30%). Un subtipo etiologico indeterminado (clasificacion TOAST) era mas frecuente en pacientes con cancer (71% frente a 20%). Conclusion. Complicaciones hemorragicas graves, potenciadas por el rtPA, pueden incrementar el riesgo de morbilidad y mortalidad. Sin embargo, pacientes seleccionados con cancer que padecen un ictus isquemico agudo pueden beneficiarse del tratamiento con rtPA. Un cancer activo no deberia considerarse una contraindicacion de uso de rtPA, aunque debe evaluarse el riesgo de complicaciones y la esperanza de vida para tomar la decision.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/complicações , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Acidente Vascular Cerebral/complicações
9.
Braz. j. biol ; 82: 1-8, 2022. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468526

RESUMO

Hops is a new culture in Brazil. Tissue culture can be an important technique for rapid hop propagation. This paper aims to characterize responses from different genotypes under different growth regulators through the interrelationship of response variables important to hop in vitro growth. Three genotypes were cultivated in six culture media with different combinations of growth regulators, BAP (6-benzylaminopurine), IAA (3-indolacetic acid) and GA3 (gibberellic acid). The means were compared by orthogonal contrasts and the interrelationship of the response variables was performed by path analysis. American genotypes showed favorable root development under the BAP + IAA combination, while the use of IAA improved shoot development. The origin of genotypes was important for defining the best protocol for in vitro cultivation. The path coefficient showed that the variable number of shoots has stronger direct effect on the number of nodal segments. Additionally, in tissue culture assays, the use of a covariable and proper error distribution significantly increased experimental accuracy.


O lúpulo é uma nova cultura no Brasil. A cultura de tecidos pode ser uma técnica importante para a propagação rápida do lúpulo. Este artigo tem como objetivo caracterizar respostas de diferentes genótipos sob diferentes reguladores de crescimento através da inter-relação de variáveis de resposta importantes para o crescimento in vitro. Três genótipos foram cultivados em seis meios de cultura com diferentes combinações de reguladores de crescimento, BAP (6-benzilaminopurina), AIA (ácido 3-indolacético) e GA3 (ácido giberélico). As médias foram comparadas por contrastes ortogonais e a inter-relação das variáveis de resposta foi realizada por análise de trilha. Os genótipos americanos apresentaram desenvolvimento radicular favorável sob a combinação BAP + AIA, enquanto o uso do AIA melhorou o desenvolvimento da parte aérea. A origem dos genótipos foi importante para definir o melhor protocolo para o cultivo in vitro. O coeficiente de trilha mostrou que a variável número de brotos tem um efeito direto mais forte no número de segmentos nodais. Adicionalmente, em experimentos com cultura de tecidos, o uso de uma covariável e distribuição de erro adequada aumentou significativamente a precisão experimental.


Assuntos
Humulus/crescimento & desenvolvimento , Humulus/genética , Melhoramento Genético/métodos , Reguladores de Crescimento de Plantas/análise , Técnicas In Vitro
10.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468713

RESUMO

Abstract Hops is a new culture in Brazil. Tissue culture can be an important technique for rapid hop propagation. This paper aims to characterize responses from different genotypes under different growth regulators through the interrelationship of response variables important to hop in vitro growth. Three genotypes were cultivated in six culture media with different combinations of growth regulators, BAP (6-benzylaminopurine), IAA (3-indolacetic acid) and GA3 (gibberellic acid). The means were compared by orthogonal contrasts and the interrelationship of the response variables was performed by path analysis. American genotypes showed favorable root development under the BAP + IAA combination, while the use of IAA improved shoot development. The origin of genotypes was important for defining the best protocol for in vitro cultivation. The path coefficient showed that the variable number of shoots has stronger direct effect on the number of nodal segments. Additionally, in tissue culture assays, the use of a covariable and proper error distribution significantly increased experimental accuracy.


Resumo O lúpulo é uma nova cultura no Brasil. A cultura de tecidos pode ser uma técnica importante para a propagação rápida do lúpulo. Este artigo tem como objetivo caracterizar respostas de diferentes genótipos sob diferentes reguladores de crescimento através da inter-relação de variáveis de resposta importantes para o crescimento in vitro. Três genótipos foram cultivados em seis meios de cultura com diferentes combinações de reguladores de crescimento, BAP (6-benzilaminopurina), AIA (ácido 3-indolacético) e GA3 (ácido giberélico). As médias foram comparadas por contrastes ortogonais e a inter-relação das variáveis de resposta foi realizada por análise de trilha. Os genótipos americanos apresentaram desenvolvimento radicular favorável sob a combinação BAP + AIA, enquanto o uso do AIA melhorou o desenvolvimento da parte aérea. A origem dos genótipos foi importante para definir o melhor protocolo para o cultivo in vitro. O coeficiente de trilha mostrou que a variável número de brotos tem um efeito direto mais forte no número de segmentos nodais. Adicionalmente, em experimentos com cultura de tecidos, o uso de uma covariável e distribuição de erro adequada aumentou significativamente a precisão experimental.

11.
Braz. j. biol ; 82: e242596, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278487

RESUMO

Hops is a new culture in Brazil. Tissue culture can be an important technique for rapid hop propagation. This paper aims to characterize responses from different genotypes under different growth regulators through the interrelationship of response variables important to hop in vitro growth. Three genotypes were cultivated in six culture media with different combinations of growth regulators, BAP (6-benzylaminopurine), IAA (3-indolacetic acid) and GA3 (gibberellic acid). The means were compared by orthogonal contrasts and the interrelationship of the response variables was performed by path analysis. American genotypes showed favorable root development under the BAP + IAA combination, while the use of IAA improved shoot development. The origin of genotypes was important for defining the best protocol for in vitro cultivation. The path coefficient showed that the variable number of shoots has stronger direct effect on the number of nodal segments. Additionally, in tissue culture assays, the use of a covariable and proper error distribution significantly increased experimental accuracy.


O lúpulo é uma nova cultura no Brasil. A cultura de tecidos pode ser uma técnica importante para a propagação rápida do lúpulo. Este artigo tem como objetivo caracterizar respostas de diferentes genótipos sob diferentes reguladores de crescimento através da inter-relação de variáveis de resposta importantes para o crescimento in vitro. Três genótipos foram cultivados em seis meios de cultura com diferentes combinações de reguladores de crescimento, BAP (6-benzilaminopurina), AIA (ácido 3-indolacético) e GA3 (ácido giberélico). As médias foram comparadas por contrastes ortogonais e a inter-relação das variáveis de resposta foi realizada por análise de trilha. Os genótipos americanos apresentaram desenvolvimento radicular favorável sob a combinação BAP + AIA, enquanto o uso do AIA melhorou o desenvolvimento da parte aérea. A origem dos genótipos foi importante para definir o melhor protocolo para o cultivo in vitro. O coeficiente de trilha mostrou que a variável número de brotos tem um efeito direto mais forte no número de segmentos nodais. Adicionalmente, em experimentos com cultura de tecidos, o uso de uma covariável e distribuição de erro adequada aumentou significativamente a precisão experimental.


Assuntos
Reguladores de Crescimento de Plantas , Brasil , Brotos de Planta/genética , Meios de Cultura , Genótipo
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 2610-2613, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29060434

RESUMO

There are several electronic stethoscopes available on the market today, with a very high potential for healthcare namely telemedicine, assisted decision and education. However, there are no recent comparatives studies published about the recording quality of auscultation sounds. In this study we aim to: a) define a ranking, according to experts opinion of 6 of the most relevant electronic stethoscopes on the market today; b) verify if there are any relations between a stethoscope's performance and the type of pathology present; c) analyze if some pathologies are more easily identified than others when using electronic auscultation. Our methodology consisted in creating two study groups: the first group included 18 cardiologists and cardiology house officers, acting as the gold standard of this work. The second included 30 medical students. Using a database of heart sounds recorded in real hospital environments, we applied questionnaires to observers from each group. The first group listened to 60 cardiac auscultations recorded by the 6 stethoscopes, and each one was asked to identify the pathological sound present: aortic stenosis, mitral regurgitation or normal. The second group was asked to choose, between two auscultation recordings, using as criteria the best sound quality for the identification of pathological sounds. Results include a total of 1080 evaluations, in which 72% of cases were correctly diagnosed. A detailed breakdown of these results is presented in this paper. As conclusions, results showed that the impact of the differences between stethoscopes is very small, given that we did not find statistically significant differences between all pairs of stethoscopes. Normal sounds showed to be easier to identify than pathological sounds, but we did not find differences between stethoscopes in this identification.


Assuntos
Auscultação Cardíaca , Ruídos Cardíacos , Estetoscópios
14.
Conserv Physiol ; 4(1): cov064, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27293744

RESUMO

The sea lamprey, Petromyzon marinus, is an anadromous, semelparous species that is vulnerable to endangered in parts of its native range due in part to loss of spawning habitat because of man-made barriers. The ability of lampreys to return to the ocean or estuary and search out alternative spawning river systems would be limited by their osmoregulatory ability in seawater. A reduction in tolerance to salinity has been documented in migrants, although the underlying mechanisms have not been characterized. We examined the capacity for marine osmoregulation in upstream spawning migrants by characterizing the physiological effects of salinity challenge from a molecular perspective. Estuarine-captured migrants held in freshwater (FW) for ∼1 week (short-term acclimation) or 2 months (long-term acclimation) underwent an incremental salinity challenge until loss of equilibrium occurred and upper thresholds of 25 and 17.5, respectively, occurred. Regardless of salinity tolerance, all lamprey downregulated FW ion-uptake mechanisms [gill transcripts of Na(+):Cl(-) cotransporter (NCC/slc12a3) and epithelial Na(+) channel (ENaC/scnn1) and kidney Na(+)/K(+)-ATPase (NKA) protein and activity but not transcript]. At their respective salinity limits, lamprey displayed a clear osmoregulatory failure and were unable to regulate [Na(+)] and [Cl(-)] in plasma and intestinal fluid within physiological limits, becoming osmocompromised. A >90% drop in haematocrit indicated haemolysis, and higher plasma concentrations of the cytosolic enzymes alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase indicated damage to other tissues, including liver. However, >80% of short-term FW-acclimated fish were able to osmoregulate efficiently, with less haemolysis and tissue damage. This osmoregulatory ability was correlated with significant upregulation of the secretory form of Na(+):K(+):2Cl(-) cotransporter (NKCC1/slc12a2) transcript levels and the re-emergence of seawater-type ionocytes detected through immunohistochemical NKA immunoreactivity in the gill, the central ionoregulatory organ. This work sheds light on the molecular and physiological limits to the potential return to seawater for lampreys searching for alternative FW systems in which to spawn.

15.
Sci Rep ; 6: 33954, 2016 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-27703170

RESUMO

Carbonic anhydrase plays a key role in CO2 transport, acid-base and ion regulation and metabolic processes in vertebrates. While several carbonic anhydrase isoforms have been identified in numerous vertebrate species, basal lineages such as the cyclostomes have remained largely unexamined. Here we investigate the repertoire of cytoplasmic carbonic anhydrases in the sea lamprey (Petromyzon marinus), that has a complex life history marked by a dramatic metamorphosis from a benthic filter-feeding ammocoete larvae into a parasitic juvenile which migrates from freshwater to seawater. We have identified a novel carbonic anhydrase gene (ca19) beyond the single carbonic anhydrase gene (ca18) that was known previously. Phylogenetic analysis and synteny studies suggest that both carbonic anhydrase genes form one or two independent gene lineages and are most likely duplicates retained uniquely in cyclostomes. Quantitative PCR of ca19 and ca18 and protein expression in gill across metamorphosis show that the ca19 levels are highest in ammocoetes and decrease during metamorphosis while ca18 shows the opposite pattern with the highest levels in post-metamorphic juveniles. We propose that a unique molecular switch occurs during lamprey metamorphosis resulting in distinct gill carbonic anhydrases reflecting the contrasting life modes and habitats of these life-history stages.


Assuntos
Anidrases Carbônicas , Citoplasma , Proteínas de Peixes , Regulação Enzimológica da Expressão Gênica/fisiologia , Petromyzon , Animais , Dióxido de Carbono/metabolismo , Anidrases Carbônicas/biossíntese , Anidrases Carbônicas/genética , Citoplasma/enzimologia , Citoplasma/genética , Proteínas de Peixes/biossíntese , Proteínas de Peixes/genética , Brânquias/enzimologia , Petromyzon/genética , Petromyzon/metabolismo
16.
Tissue Cell ; 20(5): 797-807, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-18620246

RESUMO

The large central region of the mantle of Anodonta cygnea was studied using transmission and scanning electron microscopy (TEM and SEM) for ultrastructural analysis and light microscopy (LM) and TEM for cytochemical analysis. X-ray diffraction studies of the organic matrix pellicle deposited on the inner surface of the shell were also carried out. Two groups of columnar cells presenting desmosomes on the apical region were observed in the outer epithelium. One group secretes a structural and neutral mucopolysaccharide (MPS) identified with chitin, normally excreted to form the organic matrix of the shell. Another group presents numerous cytoplasmic vesicles and constitutes the predominant cells of this epithelium. Two different types of mucous cells were found in the inner epithelium. One type secretes a faintly acid mucopolysaccharide (MPS) with sulphate groups and another type secretes an association of this polysaccharide with a neutral MPS. Staining for sulfhydryl groups (probably cysteine) was also positive, suggesting the presence of proteoglycans in these secretions. A third type of cells was also observed presenting a very different ultrastructural aspect (columnar form) without large secretion masses. They may correspond to the replacing cells in this highly secretory epithelium. Elastic fibers were found on the base of the outer epithelium and amoebocytes were observed in the interepithelial tissue.

17.
Environ Pollut ; 95(3): 379-87, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-15093453

RESUMO

Effluents from three rainbow trout (Oncorhynchus mykiss) farms located in Northern Portugal were characterized and their impact on the receiving streams was evaluated. Mean fish productions in the studied fish farms were 15, 55 and 500 t of trout per year, respectively. The feeding water was abstracted from Fornelo, Inha and Coura Rivers, at flow rates ranging from 1.2 (15 t year(-1) fish farm) to 4.8 litre s(-1) per ton annual fish production (500 t year(-1) fish farm). As the water flows through the farms, net variations in the chemical characteristics were observed: a mean reduction in the dissolved oxygen (DO) concentration between 0.7 and 2.4 mg litre(-1); mean increases between 1.9 and 3.2 mg CaCO3 litre(-1) for total alkalinity, between 0.9 and 14 mg litre(-1) for BOD5, between 0.27 and 1.46 mg litre(-1) for ammonia nitrogen (NH4-N), between 0.060 and 0.579 mg litre(-1) for soluble phosphorus (PO4-P) and less than 16 mg litre(-1) for suspended solids; variations in the pH value and nitrate nitrogen concentration were not statistically significant (p<0.05). At the 500 t year(-1) fish farm it was also possible to detect net increases of total hardness (3.2 mg CaCO3 litre(-1)), electric conductivity (19 mS cm(-1)) and permanganate value (3.6 mgO2 litre(-1)). At the other farms net variations in these parameters were not significant. Net mass flow variations reported to the annual fish production are presented. The DO mass flow decreased, on average, between 255 and 549 g t(-1) of fish per day. The mean daily BOD5 increase ranged from 353 to 1510 g t(-1) of fish. The corresponding ranges for the other parameters were 105-157 g t(-1) for NH4-N, 24-62 g t(-1) for PO4-P, 348-1035 g CaCO3 t(-1) for total alkalinity and 224 x 10(6)-506 x 10(6) t(-1) for mesophilic bacteria. Daily net variations of suspended solids, total hardness, electric conductivity and permanganate value were below 1753 g t(-1), 342 g CaCO3 t(-1), 2081 mS cm t(-1) and 392 gO2 t(-1), respectively. Longitudinal concentration profiles for the most relevant parameters show the impact of the effluent discharges on the physico-chemical and bacteriological river water quality downstream from the trout farms. Analyzing the situations from a purely chemical point of view, the polluted stretches were 3, 5 and 12 km long downstream from the effluent discharges, respectively. The microbiological contamination extended over longer distances.

18.
Acta Neurol Belg ; 97(1): 36-8, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9107343

RESUMO

A clinically definite diagnosis of multiple sclerosis was done in a 61 year-old woman who displayed severe cerebellar and pyramidal tract involvement. Symptoms developed 5 years before with unsteadiness of gait and difficulties in walking. Diagnosis was supported by evoked potentials studies and magnetic resonance imaging. However, the cerebrospinal fluid (CSF) analysis was very unusual. CSF albumin and IgG concentrations were normal, as well as the IgG index. In contrast, the IgA level and the IgA index were markedly increased and the local synthesis of IgA was estimated at 31.36 mg/l. Reduction by dithiotreitol did not change the IgA level. On affinity immunoblots, oligoclonal IgA bands were not detected but oligoclonal IgG bands were present. The strong local production of IgA in this patient seems to be therefore polyclonal.


Assuntos
Imunoglobulina A/biossíntese , Esclerose Múltipla/imunologia , Medula Espinal/metabolismo , Ditioeritritol/farmacologia , Eletroencefalografia , Potenciais Somatossensoriais Evocados , Potenciais Evocados Visuais , Feminino , Humanos , Immunoblotting/métodos , Imunoglobulina A/líquido cefalorraquidiano , Imunoglobulina A/efeitos dos fármacos , Imunoglobulina G/biossíntese , Imunoglobulina G/líquido cefalorraquidiano , Pessoa de Meia-Idade , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/fisiopatologia , Medula Espinal/imunologia , Reagentes de Sulfidrila/farmacologia
19.
Mar Environ Res ; 49(5): 453-67, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11285723

RESUMO

The chronic effects of polycyclic aromatic hydrocarbons (PAHs) on ovary development, total hepatic lipids and plasma sex- and corticosteroid levels in female flounder (Platichthys flesus) were examined. Sexually mature feral female flounder were exposed via the diet to phenanthrene (0.5, 2.5 or 12.5 nmol/g food) or chrysene (0.4 nmol/g food) for 12 weeks, during the previtellogenic phase of the annual reproductive cycle. PAH exposure did not directly affect germ cell development since no structural and/or developmental differences were observed between control and exposed fish. On the contrary, all treatments resulted in altered plasma steroid levels. The most pronounced effect was the significant decrease in plasma 17 beta-estradiol to 19 +/- 11%, 27 +/- 7%, 63 +/- 20% and 61 +/- 12% in relation to control fish, respectively, in flounders exposed to 12.5, 2.5 or 0.5 nmol phenanthrene/g food and 0.4 nmol chrysene/g food. Impaired ovarian growth was not observed, most likely because experiments were ended before the period of vitellogenesis, even though a non-significant general decline in total hepatic lipids could be observed. Moreover, all exposed flounders, except fish fed with the highest amount of phenanthrene, showed a negative correlation between plasma 17 beta-estradiol and 17 alpha-hydroxyprogesterone levels (r = -0.46). One possible explanation is that PAH action may be mediated by a specific inhibition of steroidogenic enzymes. These findings provide evidence that selected PAHs are antiestrogenic xenobiotics with the capability to impair female teleost reproductive function.


Assuntos
Dieta , Linguado/sangue , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Esteroides/sangue , Corticosteroides/sangue , Corticosteroides/metabolismo , Animais , Crisenos/metabolismo , Estradiol/sangue , Feminino , Hormônios Esteroides Gonadais/sangue , Hormônios Esteroides Gonadais/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Ovário/crescimento & desenvolvimento , Fenantrenos/metabolismo
20.
Rev Lat Am Enfermagem ; 9(2): 56-60, 2001 Mar.
Artigo em Português | MEDLINE | ID: mdl-12040803

RESUMO

A nursing role that is worthy of reflection is the administration of medications, as it involves legal and ethical aspects of impact on professional practice. Errors in the administration of medications point out the responsibility of the nursing category. An adequate performance of this role enables the prevention of real errors. The purpose of this study was to analyze nursing responsibilities in the administration of medications through a bibliographical research in the Medline and Lilacs data bases (1997/1999). Results showed the lack of published works on this theme and, therefore, the need for reflections on nursing professionals participation in the administration of medications, especially concerning publications.


Assuntos
Tratamento Farmacológico , Cuidados de Enfermagem/normas , Humanos , Qualidade da Assistência à Saúde
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