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1.
Front Physiol ; 13: 837661, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225294

RESUMO

Exposure to adverse childhood experiences or early life stress experiences (ELSs) increase the risk of non-adaptive behaviors and psychopathology in adulthood. Environmental enrichment (EE) has been proposed to minimize these effects. The vast number of methodological variations in animal studies underscores the lack of systematicity in the studies and the need for a detailed understanding of how enrichment interacts with other variables. Here we evaluate the effects of environmental enrichment in male and female Wistar rats exposed to adverse early life experiences (prenatal, postnatal, and combined) on emotional (elevated plus maze), social (social interaction chamber), memory (Morris water maze) and flexibility tasks. Our results-collected from PND 51 to 64-confirmed: 1) the positive effect of environmental enrichment (PND 28-49) on anxiety-like behaviors in animals submitted to ELSs. These effects depended on type of experience and type of enrichment: foraging enrichment reduced anxiety-like behaviors in animals with prenatal and postnatal stress but increased them in animals without ELSs. This effect was sex-dependent: females showed lower anxiety compared to males. Our data also indicated that females exposed to prenatal and postnatal stress had lower anxious responses than males in the same conditions; 2) no differences were found for social interactions; 3) concerning memory, there was a significant interaction between the three factors: A significant interaction for males with prenatal stress was observed for foraging enrichment, while physical enrichment was positive for males with postnatal stress; d) regarding cognitive flexibility, a positive effect of EE was found in animals exposed to adverse ELSs: animals with combined stress and exposed to physical enrichment showed a higher index of cognitive flexibility than those not exposed to enrichment. Yet, within animals with no EE, those exposed to combined stress showed lower flexibility than those exposed to both prenatal stress and no stress. On the other hand, animals with prenatal stress and exposed to foraging-type enrichment showed lower cognitive flexibility than those with no EE. The prenatal stress-inducing conditions used here 5) did not induced fetal or maternal problems and 6) did not induced changes in the volume of the dentate gyrus of the hippocampus.

2.
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
4.
Rev. clín. esp. (Ed. impr.) ; 213(7): 330-335, oct. 2013.
Artigo em Espanhol | IBECS | ID: ibc-115614

RESUMO

Objetivo. Analizar el impacto del tipo de hospital en la supervivencia global de los pacientes con mieloma múltiple. Pacientes y método. Análisis de supervivencia de todos los pacientes (n=431) diagnosticados en 5 hospitales públicos (4 comarcales y uno universitario), durante el periodo 1993-2006. Resultados. Los pacientes atendidos en los hospitales comarcales difieren significativamente de los atendidos en el hospital de referencia en las siguientes variables: edad media (70 años [rango 31-92] versus 67,9 [rango 35-91]; p=0,038), porcentaje de pacientes en estadio iii (62,6 versus 69,1%; p=0,033), y porcentaje de pacientes sometidos a trasplante autólogo de médula ósea (8,2 versus 18,2%; p=0,026). En el análisis multivariante, las variables asociadas de forma significativa con la mortalidad fueron la edad (p<0,001), el estadio (iii respecto a i; p=0,03) y la insuficiencia renal (p=0,04). El tipo de hospital no alcanzó significación estadística (hazard ratio de 0,72 [intervalo de confianza al 95% 0,48-1,07], p=0,1). Conclusiones. El tipo de hospital no se asocia de forma significativa con la mortalidad en pacientes con mieloma múltiple. Estos datos apoyan el actual modelo de atención a estos pacientes, en el que los hospitales comarcales son responsables de su manejo primario, de forma coordinada con el hospital universitario (AU)


Objective. To analyze the impact of the type of hospital in overall survival of multiple myeloma patients. Patients and method. A survival analysis was performed of all patients (n=431) diagnosed in 5 public hospitals (4 community hospitals and one university hospital) during the period 1993-2006. Results. Patients attended to in community hospitals differ significantly from those seen in the university hospital in the following variables: mean age (70 years [31-92] versus 67.9 (35-91), P=.038); percentage of stage iii patients (62.6% versus 69.1%, P=.033), and percentage of patients who had autologous stem cell transplant (8.2% versus 18.2%, P=.026). The variables associated with mortality in the multivariate analysis were age (P<.001), stage (iii versus i; P=.03) and renal failure (P=.04). The type of hospital did not reach statistical significance (hazard ratio of 0.72 (95% confidence interval 0.48-1.07), P=.1]. Conclusions. The type of hospital is not significantly associated with mortality in multiple myeloma patients. These data support our current model of health care, in which the community hospitals are responsible for the primary care of these patients, in a coordinated work with the university hospital (AU)


Assuntos
Humanos , Masculino , Feminino , Mieloma Múltiplo/epidemiologia , Mieloma Múltiplo/prevenção & controle , Sobrevivência , /métodos , /estatística & dados numéricos , Perfil de Impacto da Doença , Fator de Impacto , Avaliação do Impacto na Saúde/normas , Avaliação do Impacto na Saúde , Estudos de Coortes
5.
Rev Clin Esp (Barc) ; 213(7): 330-5, 2013 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-23562426

RESUMO

OBJECTIVE: To analyze the impact of the type of hospital in overall survival of multiple myeloma patients. PATIENTS AND METHOD: A survival analysis was performed of all patients (n=431) diagnosed in 5 public hospitals (4 community hospitals and one university hospital) during the period 1993-2006. RESULTS: Patients attended to in community hospitals differ significantly from those seen in the university hospital in the following variables: mean age (70 years [31-92] versus 67.9 (35-91), P=.038); percentage of stage iii patients (62.6% versus 69.1%, P=.033), and percentage of patients who had autologous stem cell transplant (8.2% versus 18.2%, P=.026). The variables associated with mortality in the multivariate analysis were age (P<.001), stage (iii versus i; P=.03) and renal failure (P=.04). The type of hospital did not reach statistical significance (hazard ratio of 0.72 (95% confidence interval 0.48-1.07), P=.1]. CONCLUSIONS: The type of hospital is not significantly associated with mortality in multiple myeloma patients. These data support our current model of health care, in which the community hospitals are responsible for the primary care of these patients, in a coordinated work with the university hospital.


Assuntos
Hospitais Públicos , Mieloma Múltiplo/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Taxa de Sobrevida
6.
J Membr Biol ; 206(1): 9-16, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16440177

RESUMO

Oral L-carnitine supplementation is commonly used in sports nutrition and in medicine; however, there is controversy regarding the mechanisms that mediate intestinal L-carnitine transport. We have previously reported that the Na(+)/L-carnitine transporter OCTN2 is present in the small intestinal apical membrane. Herein we aimed to find out if this step of intestinal L-carnitine absorption is ontogenically regulated, and if so, to determine the molecular mechanism(s) involved. L-[(3)H]-Carnitine uptake was measured in the jejunum and ileum of fetuses (E17 and E21), newborn (1 day-old), suckling (15 day-old), weaning (1 month-old) and adult (2 and 6 month-old) Wistar rats. Both, Na(+) -dependent and Na(+) -independent L-carnitine uptake rates, normalized to intestinal weight, significantly increased during the late gestation period, and then declined during the suckling period. After weaning, the rate of Na(+) -dependent L-carnitine uptake is no longer measurable. In E21- fetuses and newborn rats, L-carnitine uptake was higher in the ileum than in the jejunum. The decline in Na(+) -dependent L-carnitine uptake with maturation was mediated via a decrease in the V(max) of the uptake process with no change in its apparent K(m). Semi-quantitative RT-PCR assays showed that OCTN2 mRNA levels were significantly higher in E21-fetuses and newborn rats compared to suckling rats, which were in turn significantly higher than that in adult rats. Neither retardation of weaning nor L-carnitine supplementation prevented the down-regulation of Na(+)/L-carnitine transport activity. The results demonstrate for the first time that intestinal Na(+) -dependent L-carnitine uptake activity is under genetic regulation at the transcriptional level.


Assuntos
Envelhecimento/metabolismo , Carnitina/farmacocinética , Intestino Delgado/embriologia , Intestino Delgado/metabolismo , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Sódio/metabolismo , Administração Oral , Animais , Animais Recém-Nascidos , Carnitina/administração & dosagem , Taxa de Depuração Metabólica , Ratos , Ratos Wistar , Membro 5 da Família 22 de Carreadores de Soluto , Distribuição Tecidual
7.
J Cell Physiol ; 202(3): 929-35, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15389639

RESUMO

L-carnitine transport has been measured in enterocytes and basolateral membrane vesicles (BLMV) isolated from chicken intestinal epithelia. In the nominally Na+-free conditions chicken enterocytes take up L-carnitine until the cell to medium L-carnitine ratio is 1. This uptake was inhibited by L-carnitine, D-carnitine, gamma-butyrobetaine, acetylcarnitine, tetraethylammonium (TEA), and betaine. L-3H-carnitine uptake into BLMV showed no overshoot, and it was (i) Na+-independent, (ii) trans-stimulated by intravesicular L-carnitine, and (iii) cis-inhibited by TEA and cold L-carnitine. L-3H-carnitine efflux from L-3H-carnitine preloaded enterocytes was also Na+-independent, and trans-stimulated by L-carnitine, D-carnitine, gamma-butyrobetaine, acetylcarnitine, TEA, and betaine. Both, uptake and efflux of L-carnitine were inhibited by verapamil and unaffected by either extracellular pH or palmitoyl-L-carnitine. RT-PCR with specific primers for the mouse OCTN3 transporter revealed the existence of OCTN3 mRNA in mouse intestine, which was confirmed by in situ hybridization studies. Immunohystochemical analysis showed that OCTN3 protein was mainly associated with the basolateral membrane of rat and chicken enterocytes, whereas OCTN2 was detected at the apical membrane. In conclusion, the results demonstrate for the first time that (i) mammalian small intestine expresses OCTN3 mRNA along the villus and (ii) that OCTN3 protein is located in the basolateral membrane. They also suggest that OCTN3 could mediate the passive, Na+ and pH-independent L-carnitine transport activity measured in the three experimental conditions.


Assuntos
Carnitina/metabolismo , Membrana Celular/metabolismo , Enterócitos/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Sódio/metabolismo , Animais , Transporte Biológico Ativo , Polaridade Celular , Galinhas , Enterócitos/citologia , Intestino Delgado/citologia , Intestino Delgado/metabolismo , Proteínas de Membrana/genética , Camundongos , Proteínas de Transporte de Cátions Orgânicos/genética , Ensaio Radioligante , Ratos , Vesículas Transportadoras/metabolismo
8.
J Physiol ; 545(1): 133-44, 2002 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-12433955

RESUMO

In spite of all the fascinating properties of oral creatine supplementation, the mechanism(s) mediating its intestinal absorption has(have) not been investigated. The purpose of this study was to characterize intestinal creatine transport. [(14)C] creatine uptake was measured in chicken enterocytes and rat ileum, and expression of the creatine transporter CRT was examined in human, rat and chicken small intestine by reverse transcription-polymerase chain reaction, Northern blot, in situ hybridization, immunoblotting and immunohistochemistry. Results show that enterocytes accumulate creatine against its concentration gradient. This accumulation was electrogenic, Na(+)- and Cl(-)-dependent, with a probable stoichiometry of 2 Na(+): 1 Cl(-): 1 creatine, and inhibited by ouabain and iodoacetic acid. The kinetic study revealed a K(m) for creatine of 29 microM. [(14)C] creatine uptake was efficiently antagonized by non-labelled creatine, guanidinopropionic acid and cyclocreatine. More distant structural analogues of creatine, such as GABA, choline, glycine, beta-alanine, taurine and betaine, had no effect on intestinal creatine uptake, indicating a high substrate specificity of the creatine transporter. Consistent with these functional data, messenger RNA for CRT was detected only in the cells lining the intestinal villus. The sequences of partial clones, and of the full-length cDNA clone, isolated from human and rat small intestine were identical to previously cloned CRT cDNAs. Immunological analysis revealed that CRT protein was mainly associated with the apical membrane of the enterocytes. This study reports for the first time that mammalian and avian enterocytes express CRT along the villus, where it mediates high-affinity, Na(+)- and Cl(-)-dependent, apical creatine uptake.


Assuntos
Cloretos/metabolismo , Intestino Delgado/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Sódio/metabolismo , Animais , Northern Blotting , Western Blotting , Galinhas , Cloretos/farmacologia , Clonagem Molecular , Creatina/farmacocinética , DNA Complementar/genética , Metabolismo Energético , Enterócitos/metabolismo , Humanos , Ílio/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Cinética , Masculino , Potenciais da Membrana/fisiologia , Proteínas de Membrana Transportadoras/genética , Ouabaína/farmacologia , Ratos , Ratos Wistar , Sódio/farmacologia , Fatores de Tempo , Distribuição Tecidual
9.
J Neurochem ; 83(3): 601-12, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12390522

RESUMO

Astrocyte and glial-neuron interactions have a critical role in brain development, which is partially mediated by glycoproteins, including adhesion molecules and growth factors. Ethanol affects the synthesis, intracellular transport, subcellular distribution and secretion of these glycoproteins, suggesting alterations in glycosylation. We analyzed the effect of long-term exposure to low doses of ethanol (30 mm) on glycosylation process in growing cultured astrocytes in vitro. Cells were incubated for short (5 min) and long (90 min) periods with several radioactively labeled carbohydrate precursors. The uptake, kinetics and metabolism of these precursors, as well as the radioactivity distribution in protein gels were analyzed. The levels of GLUT1 and mannosidase II were also determined. Ethanol increased the uptake of monosaccharides and the protein levels of GLUT1 but decreased those of mannosidase II. It altered the carbohydrate moiety of proteins and increased cell surface glycoproteins containing terminal non-reduced mannose. These results indicate that ethanol impairs glycosylation in rat astrocytes, thus disrupting brain development.


Assuntos
Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Etanol/farmacologia , Monossacarídeos/metabolismo , Animais , Astrócitos/citologia , Transporte Biológico/efeitos dos fármacos , Divisão Celular , Células Cultivadas , Eletroforese em Gel de Poliacrilamida , Transportador de Glucose Tipo 1 , Glicosilação/efeitos dos fármacos , Imuno-Histoquímica , Lectinas/química , Lectinas/toxicidade , Manose/química , Manosidases/metabolismo , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/metabolismo , Peso Molecular , Proteínas de Transporte de Monossacarídeos/metabolismo , Monossacarídeos/farmacocinética , Ácido N-Acetilneuramínico/química , Ratos , Fatores de Tempo
10.
J Membr Biol ; 185(1): 65-74, 2002 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11891565

RESUMO

The carnitine transporter OCTN2 is responsible for the renal reabsorption of filtered L-carnitine. However, there is controversy regarding the intestinal L-carnitine transport mechanism(s). In this study, the characteristics of L-carnitine transport in both, isolated chicken enterocytes and brush-border membrane vesicles (BBMV) were studied. In situ hybridization was also performed in chicken small intestine. Chicken enterocytes maintain a steady-state L-carnitine gradient of 5 to 1 and 90% of the transported L-carnitine remains in a readily diffusive form. After 5 min, L-Carnitine uptake into BBMV overshot the equilibrium value by a factor of 2.5. Concentrative L-carnitine transport is Na+-, membrane voltage-and pH-dependent, has a high affinity for L-carnitine (Km 26 - 31 microM ) and a 1:1 Na+: L-carnitine stoichiometry. L-Carnitine uptake into either enterocytes or BBMV was inhibited by excess amount of cold L-carnitine > D-carnitine = acetyl-L-carnitine = gamma-butyrobetaine > palmitoyl-L-carnitine > betaine > TEA, whereas alanine, histidine, GABA or choline were without significant effect. In situ hybridization studies revealed that only the cells lining the intestinal villus expressed OCTN2 mRNA. This is the first demonstration of the operation of a Na+/L-carnitine cotransport system in the apical membrane of enterocytes. This transporter has properties similar to those of OCTN2.


Assuntos
Transporte Biológico Ativo/fisiologia , Carnitina/farmacocinética , Enterócitos/metabolismo , Intestino Delgado/metabolismo , Microvilosidades/metabolismo , Proteínas de Transporte de Cátions Orgânicos , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Proteínas de Transporte , Sistema Livre de Células , Células Cultivadas , Galinhas , Enterócitos/química , Enterócitos/citologia , Enterócitos/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Hibridização in Situ Fluorescente/métodos , Intestino Delgado/química , Intestino Delgado/citologia , Intestino Delgado/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Proteínas de Membrana , Microvilosidades/química , Microvilosidades/efeitos dos fármacos , Microvilosidades/ultraestrutura , Modelos Biológicos , Técnicas de Sonda Molecular , Ligação Proteica , Sensibilidade e Especificidade , Sódio/farmacologia , Membro 5 da Família 22 de Carreadores de Soluto , Temperatura , Vesículas Transportadoras/metabolismo
11.
Traffic ; 2(10): 717-26, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11576448

RESUMO

The morphology and subcellular positioning of the Golgi complex depend on both microtubule and actin cytoskeletons. In contrast to microtubules, the role of actin cytoskeleton in the secretory pathway in mammalian cells has not been clearly established. Using cytochalasin D, we have previously shown that microfilaments are not involved in the endoplasmic reticulum-Golgi membrane dynamics. However, it has been reported that, unlike botulinum C2 toxin and latrunculins, cytochalasin D does not produce net depolymerization of actin filaments. Therefore, we have reassessed the functional role of actin microfilaments in the early steps of the biosynthetic pathway using C2 toxin and latrunculin B. The anterograde endoplasmic reticulum-to-Golgi transport monitored with the vesicular stomatitis virus-G protein remained unaltered in cells treated with cytochalasin D, latrunculin B or C2 toxin. Conversely, the brefeldin A-induced Golgi membrane fusion into the endoplasmic reticulum, the Golgi-to-endoplasmic reticulum transport of a Shiga toxin mutant form, and the subcellular distribution of the KDEL receptor were all impaired when actin microfilaments were depolymerized by latrunculin B or C2 toxin. These findings, together with the fact that COPI-coated and uncoated vesicles contain beta/gamma-actin isoforms, indicate that actin microfilaments are involved in the endoplasmic reticulum/Golgi interface, facilitating the retrograde Golgi-to-endoplasmic reticulum membrane transport, which could be mediated by the orchestrated movement of transport intermediates along microtubule and microfilament tracks.


Assuntos
Actinas/metabolismo , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Glicoproteínas de Membrana , Toxina Shiga/metabolismo , Proteínas do Envelope Viral/metabolismo , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Actinas/efeitos dos fármacos , Animais , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Toxinas Botulínicas/farmacologia , Brefeldina A/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Citocalasina D/farmacologia , Complexo de Golgi/efeitos dos fármacos , Células HeLa/efeitos dos fármacos , Células HeLa/metabolismo , Humanos , Membranas Intracelulares/metabolismo , Mamíferos/metabolismo , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Receptores de Peptídeos/metabolismo , Tiazóis/farmacologia , Tiazolidinas
12.
Biochim Biophys Acta ; 1512(2): 225-30, 2001 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-11406099

RESUMO

The presence of a Na(+)/D-mannose cotransport activity in brush-border membrane vesicles (BBMV), isolated from either rat small intestine or rat kidney cortex, is examined. In the presence of an electrochemical Na(+) gradient, but not in its absence, D-mannose was transiently accumulated by the BBMV. D-Mannose uptake into the BBMV was energized by both the electrical membrane potential and the Na(+) chemical gradient. D-Mannose transport vs. external D-mannose concentration can be described by an equation that represents a superposition of a saturable component and another component that cannot be saturated up to 50 microM D-mannose. D-Mannose uptake was inhibited by D-mannose >> D-glucose>phlorizin, whereas for alpha-methyl glucopyranoside the order was D-glucose=phlorizin >> D-mannose. The initial rate of D-mannose uptake increased as the extravesicular Na(+) concentration increased, with a Hill coefficient of 1, suggesting that the Na(+):D-mannose cotransport stoichiometry is 1:1. It is concluded that both rat intestinal and renal apical membrane have a concentrative, saturable, electrogenic and Na(+)-dependent D-mannose transport mechanism, which is different from SGLT1.


Assuntos
Mucosa Intestinal/fisiologia , Intestino Delgado/fisiologia , Córtex Renal/fisiologia , Manose/metabolismo , Microvilosidades/fisiologia , Sódio/metabolismo , Animais , Transporte Biológico , Membrana Celular/metabolismo , Membrana Celular/fisiologia , Jejuno/fisiologia , Cinética , Masculino , Potenciais da Membrana , Metilglucosídeos/metabolismo , Microvilosidades/metabolismo , Concentração Osmolar , Ratos , Ratos Wistar
13.
Drugs ; 61(2): 163-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11270934

RESUMO

Currently, antibacterial activity is measured primarily via in vitro laboratory tests. Clinicians rely heavily upon the reported susceptibility gained via in vitro laboratory tests when choosing an antibacterial agent. An evolving concept is to utilise pharmacodynamic and pharmacokinetic drug properties in addition to in vitro susceptibility reports to assess the potential effectiveness of an antibacterial agent against a specific pathogen. This article presents examples of the utility of these concepts in terms of optimal clinical use of common antibacterials as well as more informed interpretation of the in vitro literature.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Contagem de Colônia Microbiana , Resistência Microbiana a Medicamentos , Humanos
14.
Eur J Neurosci ; 13(4): 749-56, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11207809

RESUMO

Neural cell adhesion molecule (NCAM) constitutes a group of cell surface glycoproteins that regulate cell-cell interactions in the developing and adult brain. Endocytosis is a mechanism which dynamically controls the amount of cell surface NCAM expression and may involve the rapid changes occurring in NCAM expression under certain physiological or pathological conditions. However, the endocytic pathway of NCAM is presently unknown. Using astrocytes in culture and immunofluorescence we show that NCAM is internalized and that the immunolabelling presents a high degree of colocalization with clathrin, alpha-adaptin and transferrin, suggesting that NCAM is endocytosed by a clathrin-dependent pathway. Potassium depletion which disrupts clathrin-mediated endocytosis, inhibited internalization of NCAM. Electron microscopy and immunogold studies also demonstrate that the surface of clathrin-coated vesicles are also immunolabelled for both alpha-adaptin and PSA-NCAM, the highly sialylated isoform of NCAM. Furthermore, immunoprecipation studies demonstrate that NCAM is associated with both clathrin and alpha-adaptin, a component of adaptor complex AP-2, in brain, neurons and astrocytes. These findings indicate that NCAM is mainly endocytosed via clathrin-coated vesicles, suggesting a possible mechanism that may contribute to the rapid changes in NCAM expression at the cell surface.


Assuntos
Astrócitos/metabolismo , Córtex Cerebral/metabolismo , Vesículas Revestidas por Clatrina/fisiologia , Clatrina/fisiologia , Endocitose , Proteínas do Tecido Nervoso/fisiologia , Molécula L1 de Adesão de Célula Nervosa , Moléculas de Adesão de Célula Nervosa/metabolismo , Neurônios/metabolismo , Subunidades alfa do Complexo de Proteínas Adaptadoras , Proteínas Adaptadoras de Transporte Vesicular , Animais , Astrócitos/ultraestrutura , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/embriologia , Clorpromazina/farmacologia , Técnica Indireta de Fluorescência para Anticorpo , Imuno-Histoquímica , Substâncias Macromoleculares , Proteínas de Membrana/análise , Proteínas de Membrana/fisiologia , Moléculas de Adesão de Célula Nervosa/análise , Neurônios/ultraestrutura , Potássio/fisiologia , Isoformas de Proteínas/análise , Isoformas de Proteínas/metabolismo , Ratos , Ácidos Siálicos/análise
15.
Rev Esp Cardiol ; 54(12): 1426-38, 2001 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-11754789

RESUMO

The results of the Registry of the Working Group on Hemodynamics and Interventional Cardiology of the Spanish Society of Cardiology for 2000 are presented. Date came from 100 centers representing all the cardiac catheterization laboratories in Spain; 93 centers performed mainly adult catheterization and 7 carried out only pediatric procedures. In 2000, 88,339 diagnostic catheterization procedures were performed (73,382 coronary angiograms), representing a total increase of 12.5% over 1999. The population-adjusted rate was 1,825 coronary angiograms per 106 inhabitants. With a total of 26,993 procedures and a rate of coronary interventions per 106 inhabitants of 671, coronary intervention increased by 17% over figures for 1999. Coronary stents were the devices used most often, with 29,504 implanted in 2000; stenting accounted for 77.2% of procedures, a 30.5% increase over 1999. The increase in direct stenting without predilatation was noteworthy. Direct stenting was done in 8,778 procedures (38.9% of the total), an increase of 131% compared to 1999. IIb-IIIa glycoprotein were used in 4,700 coronary interventions (17%). Angioplasty, performed in 3,128 cases of acute myocardial infarction, accounted for 11.6% of coronary interventions 33.5% more than in 1999. A decrease of 6.5% in valvuloplastics occurred, attributable to the performance of fewer mitral valve repairs (493 vs 525 in 2000 and 1999, respectively). Pediatric procedures increased by 20.5%, from 678 to 817 cases. In conclusion, we would like to underline the high rate of reporting by laboratories, through which the Registry has been able to compile data that are highly representative of the hemodynamic activity in Spain.


Assuntos
Serviço Hospitalar de Cardiologia/estatística & dados numéricos , Cardiologia , Hemodinâmica , Sistema de Registros , Inquéritos e Questionários , Humanos , Sociedades Médicas , Espanha
16.
J Invasive Cardiol ; 12(11): 586-8, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11060572

RESUMO

Calcium antagonists are the treatment of choice in vasospasm angina when no stenosis or mild stenosis are present. We present a case in which ergonovine echocardiography showed vasospasm of the right coronary artery despite optimal medical treatment. Stenting of a mild stenosis in that artery successfully controlled vasospasm and a pre-discharge ergonovine echocardiographic test was negative. The patient remains asymptomatic one year after stenting.


Assuntos
Angina Pectoris Variante/terapia , Vasos Coronários , Stents , Angina Pectoris Variante/diagnóstico por imagem , Bloqueadores dos Canais de Cálcio/uso terapêutico , Ecocardiografia , Ergonovina , Feminino , Humanos , Pessoa de Meia-Idade
17.
Bull Menninger Clin ; 64(3): 317-43, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10998811

RESUMO

The authors focus on infant mental health interventions during pregnancy in response to stressors, behaviors, and difficulties experienced by the mother-to-be (as well as by the father-to-be and surrounding family or support system) that are likely to have a negative impact on the growth, development, behavior, and psychological environment of the baby. After summarizing normal tensions and psychological tasks, the authors focus on difficulties during pregnancy: "pathology of destiny," excessive anxiety, domestic violence, fear of becoming a mother, denial of pregnancy, somatic complaints, inadequate weight gain and eating disorders, and depression. The effects of these difficulties on the baby, as well as intervention techniques (including a psychosocial support group), are highlighted.


Assuntos
Gravidez/psicologia , Cuidado Pré-Natal , Efeitos Tardios da Exposição Pré-Natal , Psicoterapia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Relações Mãe-Filho
18.
Int J Dev Biol ; 44(2): 209-21, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10794079

RESUMO

Endocytosis constitutes an essential process in the regulation of the expression of cell surface molecules and receptors and, therefore, could participate in the neural-glial interactions occurring during brain development. However, the relationship between endocytic pathways in astroglial cells under physiological and pathological conditions remains poorly understood. We analyzed the endocytosis and transcytosis processes in growing astrocytes and the possible effect of ethanol on these processes. Evidence demonstrates that ethanol affects endocytosis in the liver and we showed that ethanol exposure during brain development alters astroglial development changing plasma membrane receptors and surface glycoprotein composition. To study these processes we use several markers for receptor-mediated endocytosis, fluid phase endocytosis and non-specific endocytosis. These markers were labeled for fluorescence microscopy and electron microscopy. 125I-BSA was used to study the effect of ethanol on the internalization and recycling of this macromolecule. The distribution of several proteins involved in endocytosis (caveolin, clathrin, rab5 and beta-COP) was analyzed using immunofluorescence, immunoelectron microscopy and immunoblotting. Our results indicate that growing astrocytes have a developed endocytic system mainly composed of caveolae, clathrin coated pits and vesicles, tubulo-vesicular and spheric endosomes, multivesicular bodies and lysosomes. Ethanol exposure induces a fragmentation of tubular endosomes, decreases the internalization of 125I-BSA, alters the processing of internalized BSA, and decreases the levels of caveolin, clathrin, rab5 and beta-COP. These results indicate that ethanol alters the endocytosis and transcytosis processes and impairs protein trafficking in astrocytes, which could perturb astrocyte surface expression of molecules involved in neuronal migration and maturation during brain development.


Assuntos
Astrócitos/metabolismo , Caveolinas , Endocitose , Neurônios/fisiologia , Animais , Astrócitos/efeitos dos fármacos , Western Blotting , Encéfalo/embriologia , Caveolina 1 , Células Cultivadas , Depressores do Sistema Nervoso Central/farmacologia , Clatrina/metabolismo , Proteína Coatomer/metabolismo , Etanol/farmacologia , Ferritinas/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , Imuno-Histoquímica , Proteínas de Membrana/metabolismo , Microscopia Eletrônica , Microscopia de Fluorescência , Neurônios/efeitos dos fármacos , Ratos , Albumina Sérica/metabolismo , Fatores de Tempo , Proteínas rab5 de Ligação ao GTP/metabolismo
19.
Expert Opin Pharmacother ; 1(3): 489-505, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11249533

RESUMO

The global challenge of optimally treating bacterial infections is continuously evolving. Azithromycin, the first azalide antibiotic, presents pharmacokinetics and pharmacodynamics that allow for a simple dosing regimen with minimal side effects. Current azithromycin uses include a variety of community-acquired respiratory tract, skin and soft tissue, and sexually transmitted disease infections. Azithromycin has also demonstrated substantial activity against atypical organisms such as Mycobacterium avium complex (MAC) and Chlamydia trachomatis. Due to a never-ending need for new antibiotic therapies, several other potential indications for azithromycin are being researched. This article will present various current research associated with azithromycin's potential use for malaria, trachoma, coronary artery disease (CAD), Pseudomonas aeruginosa infections, erythema migrans, short-term therapy for respiratory infections, typhoid, cryptosporidiosis, pelvic inflammatory disease, acne, Mediterranean spotted fever and MAC. As bacterial and parasite resistance patterns fluctuate globally, azithromycin may be an alternative therapy for the previously mentioned indications, which will also enhance patient compliance and therefore effectively eradicate infection worldwide.


Assuntos
Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Ensaios Clínicos como Assunto , Humanos , Malária/tratamento farmacológico , Malária/patologia
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