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Even though, it has long been considered as a passive channel allowing communication between the systemic and pulmonary circulations, it is now clearly established that the right ventricle plays an essential role in cardio-pulmonary couple physiology. Its failure results in a clinical presentation that reflects the systemic congestion and reduced cardiac output. It is the consequence of two pathological situations frequently encountered in intensive care including pulmonary vascular resistance increase and right ventricle contraction alteration. Mechanical ventilation, certain drugs and volume overload can also participate. The management of the acute right heart failure is based on the combination of supportive treatment and causal treatment, specific to the etiology. Supportive therapy aims to optimize filling pressures, reduce afterload and support cardiac contractibility. With the growing number of therapeutic options used according to co-morbidities, decision-making by a multidisciplinary heart team seems essential.
Même s'il a été longtemps considéré comme un conduit passif permettant la communication entre les circulations systémique et pulmonaire, il est maintenant clairement établi que le ventricule droit joue un rôle essentiel dans la physiologie du couple cardio-pulmonaire. Sa défaillance est à l'origine d'un tableau clinique secondaire à la congestion systémique et à la réduction du débit cardiaque. Elle est la conséquence de deux situations pathologiques fréquemment rencontrées incluant l'augmentation des résistances vasculaires pulmonaires et l'altération de la contraction du ventricule droit. La ventilation mécanique, certains médicaments et la surcharge volémique peuvent également y participer. La prise en charge de l'insuffisance cardiaque aiguë repose sur l'association d'un traitement supportif et d'un traitement causal, spécifique à l'étiologie. Le traitement supportif vise à optimaliser les pressions de remplissage, réduire la postcharge et soutenir la contractilité myocardique. Avec le nombre croissant d'options thérapeutiques utilisées en fonction des comorbidités, la prise de décision par une équipe cardiologique multidisciplinaire est indispensable.
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Insuficiencia Cardíaca , Disfunción Ventricular Derecha , Cuidados Críticos , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/terapia , Ventrículos Cardíacos , Humanos , Respiración Artificial , Disfunción Ventricular Derecha/etiología , Disfunción Ventricular Derecha/terapiaRESUMEN
Alcohol consumption is a serious problem in terms of public health because it remains a major cause of illness and premature death. The effects of alcohol on cardiovascular system are particularly complex. Current data report both favourable and adverse effects depending on the level of consumption, the type of alcohol consumed and the pathology considered. The goal of this review is to describe the spectrum of cardiovascular events associated with alcohol consumption.
La consommation d'alcool représente une problématique sérieuse en termes de santé publique puisqu'elle demeure une cause majeure de maladie et de décès prématuré. Les effets de l'alcool sur le système cardiovasculaire sont particulièrement complexes. Les données actuelles rapportent à la fois des effets favorables et des effets néfastes en fonction du niveau de consommation, du type d'alcool consommé et de la pathologie considérée. L'objectif de cet article est de décrire le spectre des manifestations cardiovasculaires les plus fréquentes liées à la prise d'alcool.
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Consumo de Bebidas Alcohólicas , Enfermedades Cardiovasculares , Sistema Cardiovascular , Consumo de Bebidas Alcohólicas/efectos adversos , Enfermedades Cardiovasculares/inducido químicamente , Sistema Cardiovascular/efectos de los fármacos , Humanos , Salud Pública , Factores de RiesgoRESUMEN
In the skeletal muscle tissue, cells are organized following an anisotropic architecture, which is both required during myogenesis when muscle precursor cells fuse to generate myotubes and for its contractile function. To build an in vitro skeletal muscle tissue, it is therefore essential to develop methods to organize cells in an anisotropic fashion, which can be particularly challenging, especially in 3D. In this study, we present a versatile muscle-on-chip system with adjustable collagen hollow tubes that can be seeded with muscle precursor cells. The collagen acts both as a tube-shaped hollow mold and as an extracellular matrix scaffold that can house other cell types for co-culture. We found that the diameter of the channel affects the organization of the muscle cells and that proper myogenesis was obtained at a diameter of 75 µm. In these conditions, muscle precursor cells fused into long myotubes aligned along these collagen channels, resulting in a fascicle-like structure. These myotubes exhibited actin striations and upregulation of multiple myogenic genes, reflecting their maturation. Moreover, we showed that our chip allowed muscle tissue culture and maturation over a month, with the possibility of fibroblast co-culture embedding in the collagen matrix.
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OBJECTIVES: To report indications and risk factors for effective termination of pregnancy (TOP) when multidisciplinary prenatal diagnosis centers refuse request for TOP. METHODS: This is a retrospective study from a French national registry between 2005 and 2009. Indication groups for TOP refusal were created. Risk factors for pregnancy outcomes and effective TOP were determined by multinomial logistic regression model. RESULTS: The overall number of TOP refusals was 573. Indications were single malformations (37%), chromosomal abnormalities (16.6%), hygroma (5.2%), potential fetopathies (11%), maternal indications (17.4%), and other indications (12.7%). Pregnancy outcomes were live infants (35.1%), effective TOP (36.3%), intra-uterine fetal death (5.4%), and lost to follow-up (23.2%). Logistic regression model showed an increased likelihood of effective TOP in groups with single malformations [odds ratio (OR) 3.4, 95% confidence interval (CI) 1.6-7.4], chromosomal abnormalities (OR 3, 95% CI 1.2-7.2), and hygromas (OR 19.6, 95% CI 2.3-16.8) compared with other groups. An increased likelihood of effective TOP was also reported when the request was made at first (OR 29.5, 95% CI 10-16.7) and second (OR 6.3, 95% CI 2.3-16.7) trimesters compared with the third trimester. CONCLUSIONS: Effective TOP is particularly frequent when requested during the first trimester and in cases of structural anomalies of the fetus.
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Aborto Inducido , Disentimientos y Disputas , Resultado del Embarazo/epidemiología , Diagnóstico Prenatal , Negativa al Tratamiento , Femenino , Francia/epidemiología , Hospitales Generales/estadística & datos numéricos , Humanos , Recién Nacido , Centros de Salud Materno-Infantil/estadística & datos numéricos , Embarazo , Atención Prenatal/estadística & datos numéricos , Sistema de Registros/estadística & datos numéricos , Estudios RetrospectivosRESUMEN
Radiopharmaceuticals extravasation is rare but may have serious clinical issues. Because no specific recommendations are being proposed to date, the goals of our working group created within the French Society of Radiopharmacy are to determine preventive measures and to establish a pragmatic management of extravasation of these drugs. Our preventive measures are to recognize the symptoms (erythema, venous discoloration, swelling), to know the risk factors (which are related to radiopharmaceutical, patient, site of injection, injection technique) and severity (from erythema to skin necrosis, depending on the radionuclide) and how to avoid them (training and awareness of staff, choice of injection site, route of drug administration test, use of a catheter for administration of therapeutic radiopharmaceuticals). Management should be immediate. It can be facilitated by a specific emergency kit. General measures recommended are the immediate cessation of injection, aspiration of fluid extravasation, delimitation of the extravasated area with an indelible pen, informing the doctor. Specific measures taking into account the radiotoxicity of the radionuclide and the type of radiopharmaceutical were also established. The patient should be informed by the doctor about the risks and how to take care of. Traceability of the incident must be ensured. A multidisciplinary reflexion is essential to manage the extravasation as early and effectively as possible.
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Extravasación de Materiales Terapéuticos y Diagnósticos , Radiofármacos/efectos adversos , Extravasación de Materiales Terapéuticos y Diagnósticos/prevención & control , Humanos , Inyecciones , Radiofármacos/administración & dosificación , Radiofármacos/análisis , RiesgoRESUMEN
Correlations between the morphological features of f lower buds and the developmental stages of the male gametophyte are of great practical interest as a reliable marker that accelerates and simplif ies the selection of appropriate plant material for isolated microspore culture. Microspore culture enables one to quickly obtain many pure lines of different vegetable crops, but it has not yet been widely applied in the melon (Cucumis melo L.). To successfully apply this technique in a new culture, one has to optimize many of its elements: f irst, f ind the biological markers for selecting the f lower buds containing the microspores of certain development stages. The paper presents the results of research estimating the correlations between the length and diameter of the f lower buds, the length of the visual part of the corolla, the length of the anthers and the development stages of the male gametophyte in the F1 hybrid of the Kim Hong Ngoc melon. The strongest correlation (CC = 0.885) was found for the f lower bed diameter and a strong correlation (CC = 0.880), for the bud length. The corolla's visual part was a less reliable morphological feature, and the anther's length should not be used as a parameter to predict the developmental stages of the melon's male gametophyte. It was also found that one anther could contain the microspores and pollen grains of different developmental stages. In the f lower buds less than 4 mm in length and 1.51 ± 0.02 mm in diameter prevailed tetrads, and in the buds 4.0-4.9 mm in length and 2.30 ± 0.02 mm in diameter, early microspores. The microspores of a middle stage of development prevailed in the f lower buds 5.0-5.9 mm in length and 2.32 ± 0.00 mm in diameter; mid and late vacuolated microspores, in the buds 6.0-8.9 mm in length and 2.96 ± 0.37 mm in diameter; and two-celled pollen, in the buds more than 9 mm in length and more than 3.97 ± 0.34 mm in diameter.
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Water is a vital but poorly studied component of livestock production. It is estimated that livestock industries consume 8% of the global water supply, with most of that water being used for intensive, feed-based production. This study takes a broad perspective of livestock production as a component of the human food chain, and considers the efficiency of its water use. Global models are in the early stages of development and do not distinguish between developing and developed countries, or the production systems within them. However, preliminary indications are that, when protein production is adjusted for biological value in the human diet, no plant protein is significantly more efficient at using water than protein produced from eggs, and only soybean is more water efficient than milk and goat and chicken meat. In some regions, especially developing countries, animals are not used solely for food production but also provide draught power, fibre and fertiliser for crops. In addition, animals make use of crop by-products that would otherwise go to waste. The livestock sector is the fastest-growing agricultural sector, which has led to increasing industrialisation and, in some cases, reduced environmental constraints. In emerging economies, increasing involvement in livestock is related to improving rural wealth and increasing consumption of animal protein. Water usage for livestock production should be considered an integral part of agricultural water resource management, taking into account the type of production system (e.g. grain-fed or mixed crop-livestock) and scale (intensive or extensive), the species and breeds of livestock, and the social and cultural aspects of livestock farming in various countries.
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Crianza de Animales Domésticos/normas , Ingestión de Líquidos/fisiología , Ganado/fisiología , Plantas Comestibles/fisiología , Abastecimiento de Agua/normas , Animales , Proteínas en la Dieta/provisión & distribución , Cadena Alimentaria , Humanos , Internacionalidad , Abastecimiento de Agua/economía , Abastecimiento de Agua/estadística & datos numéricosRESUMEN
BACKGROUND: The treatment of persons living with human immunodeficiency virus/acquired immune-deficiency syndrome (PLWHAs) for latent tuberculosis infection (LTBI) reduces tuberculosis (TB) morbidity. Despite a high TB burden and an expanding human immunodeficiency virus epidemic, Russia had limited data on the utility of the tuberculin skin test (TST) for LTBI diagnosis in PLWHAs. OBJECTIVE: To determine the prevalence and predictors of positive TSTs in PLWHAs in Orel Oblast. METHODS: A total of 150 consenting PLWHAs being followed up at the AIDS Center were administered a TST and a questionnaire for risk factors for LTBI. A positive TST result was defined as >or=5 mm induration. RESULTS: Of the 150 subjects, 67% were male and 74% were aged <30 years. Of the PLWHAs tested, 26% had a positive TST result, while among PLWHAs with CD4(+) >500 cells/ml, 36% were TST-positive. TST positivity varied inversely with CD4(+) cell count. Among PLWHAs with a history of injection drug use, the primary risk factor for HIV, 29 (31.9%) were positive. CONCLUSIONS: A high proportion of tested PLWHAs had a positive TST and could benefit from preventive therapy (PT) to reduce the risk of TB. A TB control programme in Russia should therefore include TST screening among PLWHAs and PT, besides active TB case finding and treatment.
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Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Prueba de Tuberculina , Tuberculosis/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Adulto , Recuento de Linfocito CD4 , Femenino , Humanos , Modelos Logísticos , Masculino , Proyectos Piloto , Prevalencia , Factores de Riesgo , Federación de Rusia/epidemiología , Encuestas y Cuestionarios , Tuberculosis/epidemiologíaRESUMEN
High-risk human papillomaviruses are the causative agents of cervical and other anogenital cancers. In these cancers, two viral oncogenes, E6 and E7, are expressed. E6 is best known for its ability to inactivate the tumor suppressor p53, which is thought to arise through ubiquitin-mediated degradation of p53 and involve a ternary complex between E6, p53 and the E3 ligase, E6AP. In mice transgenic for wild-type HPV16 E6, its expression leads to epithelial hyperplasia and an abrogation of normal cellular responses to DNA damage. Whereas only the latter phenotype is dependent upon E6's inactivation of p53, both are reduced in transgenic mice expressing an E6 mutant severely reduced in its binding to E6AP and other cellular proteins that bind E6 through a shared alpha-helix motif. Here, we investigated whether E6AP is required for the induction of the above phenotypes through the use of both E6AP-mutant and E6AP-null mice. E6, in the absence of E6AP retains an ability to induce epithelial hyperplasia, abrogate DNA damage responses and inhibit the induction of p53 protein following exposure to ionizing radiation. We conclude that E6 is able to induce both p53-dependent and p53-independent phenotypes through E6AP-independent pathways in the mouse.
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Epidermis/metabolismo , Proteínas Oncogénicas Virales/metabolismo , Fenotipo , Proteínas Represoras/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Daño del ADN , Lisina/genética , Lisina/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteínas Oncogénicas Virales/genética , Proteínas Represoras/genética , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
OBJECTIVES: Know the impact of the unplanned deliveries in a town of medium size, the characteristics of these women and maternal and neonatal risks. MATERIALS AND METHODS: This was a retrospective study conducted between January 2002 and December 2009. Unexpected delivery was defined as any delivery taking place outside of a non-elective way maternity. Each unexpected delivery was matched at nearest delivery of equivalent term, at the CHU maternity, with an onset of spontaneous labour. RESULTS: Ninety-four women gave birth unexpectedly for a total of 48,721 births (incidence of 0.19%). There was a significant difference between cases and controls for parity (1.8 versus 0.9), the lack of follow-up of pregnancy (21.3% versus 1.1%), tobacco (57.4% versus 25.5%), the socio-economic level, the type of feeding (artificial: 61.7% versus 30.6%), the home-hospital distance and obstetric follow-up. We found a significant increase in perinatal mortality (6.4% versus 1%) and stay in Neonatal ICU (19.1% versus 9.2%). The main neonatal morbidity was hypothermia. CONCLUSION: It is difficult to target a population at risk because the type of these women is non-specific. Prevention of unplanned deliveries and their morbidities through information of patients on the grounds of urgent consultation and support of the newborn to limit hypothermia.
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Parto Obstétrico/estadística & datos numéricos , Resultado del Embarazo , Adulto , Estudios de Casos y Controles , Femenino , Francia , Humanos , Embarazo , Estudios RetrospectivosRESUMEN
OBJECTIVES: To evaluate the morbidity and mortality of Candida fungemia and to assess the efficacy of low- vs high-dose amphotericin B and fluconazole vs amphotericin B in patients with candidemia. METHODS: Multicenter, prospective, observational study of 427 consecutive patients with candidemia. RESULTS: The mortality rate for patients with candidemia was 34%. The mortality rate for patients with catheter-related candidemia in whom the catheters were retained was significantly higher than that of patients in whom the catheters were removed (41% vs 21%, P < .001). We found no overall difference in mortality in patients treated with low-dose (total amphotericin B dose of < or = 500 mg) (13%) vs high-dose amphotericin B (total amphotericin B dose of > 500 mg) (15%), but the group treated with a low dose had fewer side effects (40%) than those treated with a high dose (55%) (P = .03). Fluconazole was as efficacious as amphotericin B in the therapy of candidemia, even when stratified by risk factors for mortality. Fewer side effects were seen with fluconazole (12%) compared with amphotericin B (44%) (P < .001). CONCLUSIONS: In selected patients with candidemia, low-dose amphotericin B was as efficacious as high-dose amphotericin B. Based on other studies and ours, fluconazole seems to be an alternative therapeutic option to amphotericin B in selected patients.
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Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Candidiasis/tratamiento farmacológico , Fluconazol/uso terapéutico , Fungemia/tratamiento farmacológico , Anciano , Anfotericina B/administración & dosificación , Candidiasis/etiología , Candidiasis/mortalidad , Catéteres de Permanencia/efectos adversos , Fungemia/etiología , Fungemia/mortalidad , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Factores de RiesgoRESUMEN
Nitrogen removal performance is reported for constructed wetlands treating subsurface drainage from irrigated and rain-fed dairy pastures in North Island, New Zealand. Flow-proportional sampling of inflow and outflow concentrations were combined with continuous flow records to calculate mass balances for the wetlands. Drainage flows from the irrigated catchment were 2.5-4 fold higher and N exports up to 5 fold higher per unit area than for the rain-fed catchment. Hydraulic and associated N loadings to the wetlands were highly pulsed, associated with rainfall, soil water status, and irrigation events. Transient pulses of organic nitrogen were an important form of N loss from the rain-fed landscape in the first year, and were very effectively removed in the wetland (> 90%). Median nitrate concentrations of approximately 10 g m(-3) in the drainage inflows were reduced by 15-67% during passage through the wetlands and annual nitrate-N loads by 16-61% (38-31 7 g N m(-2)y(-1)). Generation in the wetlands of net ammoniacal-N and organic-N (irrigated site) partially negated reduction in nitrate-N loads. The results show that constructed wetlands comprising 1-2% of catchment area can provide moderate reductions in TN export via pastoral drainage, but performance is markedly influenced by variations in seasonal loading and establishment/maturation factors.
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Industria Lechera , Ecosistema , Nitrógeno/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Animales , Biodegradación Ambiental , Bovinos , Nitratos/aislamiento & purificación , Movimientos del Agua , Abastecimiento de AguaRESUMEN
OBJECTIVES: To assess the changing epidemiology of candidemia in the 1990s, to evaluate the clinical implications for the presence of non-Candida albicans in blood, and to evaluate the presence of antifungal resistance in relation to prior antifungal administration. DESIGN: Multicenter prospective observational study of patients with positive blood cultures for Candida species or Torulopsis glabrata. SETTING: Four tertiary care medical centers. RESULTS: Four hundred twenty-seven consecutive patients were enrolled. The frequency of candidemia due to non-C. albicans species significantly increased in each hospital throughout the 3.5-year study period (P = 0.01). Thirteen percent of candidemias occurred in patients who were already receiving systemic antifungal agents. Candidemias developing while receiving antifungal therapy were more likely caused by non-C. albicans species than by C. albicans species (P = 0.0005). C. parapsilosis and C. krusei were more commonly seen with prior fluconazole therapy, whereas T. glabrata was more commonly seen with prior amphotericin B therapy. Candida species isolated during episodes of breakthrough candidemia exhibited a significantly higher MIC to the antifungal agent being administered (P < 0.001). CONCLUSION: In this large scale study, the non-C. albicans species, especially T. glabrata, emerged as important and frequent pathogens causing fungemia. This finding has major clinical implications given the higher complication and mortality rate associated with the non-C. albicans species. The change in the pattern of candidemia might be partly attributed to the increase in number of immunocompromised hosts and the widespread use of prophylactic or empiric antifungal therapy. This is an ominous sign given the in vitro resistance of the non-C. albicans species to currently available antifungal agents.
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Antifúngicos/uso terapéutico , Candidiasis/microbiología , Fungemia/microbiología , Anfotericina B/uso terapéutico , Candida albicans , Candidiasis/tratamiento farmacológico , Farmacorresistencia Microbiana , Fluconazol/uso terapéutico , Fungemia/tratamiento farmacológico , Humanos , Incidencia , Pruebas de Sensibilidad Microbiana , Análisis Multivariante , Estudios Prospectivos , Riesgo , Factores de RiesgoRESUMEN
In developing therapeutic reagents for the control of HIV infection, it is necessary to screen candidate products in vitro for their ability to reduce or neutralize viral infection. Although the current literature describes numerous neutralization assays, no universally accepted standards have been adopted. In this article, we briefly review the available neutralization assays and describe in detail the methods we have selected in our laboratory for the screening and characterization of reagents with potential anti-HIV properties. After evaluating many different technical protocols and experimental procedures, we have found the syncytium inhibition and syncytial focus assays to be particularly useful and have found p24 gag antigen production to be an excellent objective measure of HIV infection under a variety of conditions. These assays proved reproducible and sensitive and are suitable for use in the majority of laboratories.
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Anticuerpos Anti-VIH/inmunología , VIH-1/inmunología , VIH/inmunología , Pruebas de Neutralización , Animales , Línea Celular , Colorimetría , Efecto Citopatogénico Viral , Ensayo de Inmunoadsorción Enzimática , VIH/fisiología , Proteína p24 del Núcleo del VIH/biosíntesis , Proteína p24 del Núcleo del VIH/inmunología , Seropositividad para VIH/sangre , Seropositividad para VIH/inmunología , VIH-1/fisiología , Humanos , Mamíferos/inmunología , Pruebas de Neutralización/normas , Reproducibilidad de los Resultados , Coloración y EtiquetadoRESUMEN
Many adaptive changes occur in response to chronic or repeated stress, involving complex regulatory interactions between central stress-related afferents and the central components of the hypothalamo-pituitary-adrenal (HPA) axis. One change associated with chronic stress is an attenuation of corticosteroid receptor-mediated feedback inhibition of the HPA axis, a process thought to involve corticosteroid receptors in the hippocampus. A prominent stress-related central afferent that innervates the hippocampus and that may participate in the regulation of the HPA axis is the central noradrenergic system. Previous evidence suggests that alpha1 adrenergic receptors may down-regulate hippocampal corticosteroid receptors, and may thus contribute to stress-induced facilitation of HPA responses. In the present study, we used combined nonisotopic and radioisotopic in situ hybridization to examine the overlapping expression and co-localization of mRNA encoding the post-synaptic alpha1D adrenergic receptor subtype, the major alpha1 subtype expressed in hippocampus, with mRNA for the two corticosteroid receptor subtypes, type I (mineralocorticoid receptor, MR) and type II (glucocorticoid receptor, GR) in rat hippocampal neurons. We observed overlapping distributions and an extensive degree of co-localization of alpha1D receptor mRNA with both corticosteroid receptor subtype messages, establishing an anatomical substrate by which these two receptor systems may directly regulate each other. The potential interaction between co-localized adrenergic and corticosteroid receptors in hippocampus may contribute to stress-induced alterations in the HPA response to subsequent stress.
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Hipocampo/química , ARN Mensajero/análisis , Receptores Adrenérgicos alfa/genética , Receptores de Glucocorticoides/genética , Receptores de Mineralocorticoides/genética , Animales , Hibridación in Situ , Masculino , Neuronas/química , Ratas , Ratas Sprague-Dawley , Distribución TisularRESUMEN
Veratridine produces a marked elevation in spontaneous quantal release from nerve endings through its ability to enhance sodium-channel activity, leading to sustained membrane depolarization. In the course of an electrophysiological investigation into the effects of vesamicol, an inhibitor of the synaptic vesicle acetylcholine transporter, on veratridine-induced acetylcholine release from rat motor nerve terminals we observed that veratridine itself has an effect on miniature endplate current amplitude distributions suggestive of an effect of the compound on the filling of cholinergic synaptic vesicles with acetylcholine. This effect of veratridine is release-dependent, being inhibited by either removal of extracellular calcium ions or by the addition of the sodium channel blocking toxin, tetrodotoxin. Biochemical studies using synaptic vesicles isolated from Torpedo electroplaque confirmed the ability of veratridine to directly inhibit the vesicular transport of acetylcholine. This appears to be a consequence of its ability to dissipate the trans-vesicular membrane proton gradient, which normally drives the active transport of acetylcholine into synaptic vesicles. We discuss how such an action of veratridine could lead to the observed release-dependent effects of the compound on electrophysiologically monitored spontaneous quantal acetylcholine release. The action of veratridine on cholinergic synaptic vesicles could be of considerable import when using this agent to elicit neurotransmitter release from either peripheral or central nerve endings.
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Acetilcolina/metabolismo , Placa Motora/efectos de los fármacos , Unión Neuromuscular/efectos de los fármacos , Vesículas Sinápticas/metabolismo , Torpedo/metabolismo , Veratridina/farmacología , Animales , Órgano Eléctrico/efectos de los fármacos , Órgano Eléctrico/inervación , Órgano Eléctrico/metabolismo , Electrofisiología , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Masculino , Potenciales de la Membrana/efectos de los fármacos , Fibras Musculares Esqueléticas/efectos de los fármacos , Fármacos Neuromusculares Despolarizantes/farmacología , Piperidinas/farmacología , Ratas , Ratas Sprague-Dawley , Vesículas Sinápticas/efectos de los fármacos , Tetrodotoxina/farmacologíaRESUMEN
Viral pneumonitis can affect all age groups and normal as well as compromised hosts. This article discusses salient features of pneumonitis caused by respiratory syncytial virus, adenoviruses, varicella-zoster virus, herpes simplex virus, influenza A and B viruses, and cytomegalovirus. The clinical picture, diagnosis, treatment and prevention for each agent are discussed.
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Neumonía Viral/microbiología , Infecciones por Adenoviridae/diagnóstico , Infecciones por Adenoviridae/terapia , Varicela/diagnóstico , Varicela/terapia , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Citomegalovirus/terapia , Herpes Simple/diagnóstico , Herpes Simple/terapia , Humanos , Gripe Humana/diagnóstico , Gripe Humana/microbiología , Neumonía Viral/diagnóstico , Neumonía Viral/terapia , Infecciones por Respirovirus/diagnóstico , Infecciones por Respirovirus/terapiaRESUMEN
As specialized laboratory tests became more widely available, Legionella species were found to be common causes of nosocomial and community-acquired pneumonia. Patients with chronic lung disease and organ transplants are at greatest risk. Clinical manifestations are non-specific, although fever greater than 39 degrees C and diarrhea are common. Erythromycin remains the antibiotic of choice, although many alternative agents are available. Once cases are discovered, a search for the organism in water distribution systems and respiratory equipment can be fruitful. Disinfection of water distribution systems by superheating and flushing or by hyperchlorination is feasible.
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Enfermedad de los Legionarios , Eritromicina/uso terapéutico , Humanos , Legionella/aislamiento & purificación , Enfermedad de los Legionarios/diagnóstico , Enfermedad de los Legionarios/tratamiento farmacológico , Enfermedad de los Legionarios/prevención & controlRESUMEN
Photodynamic therapy has demonstrated efficacy toward primary, metastatic and recurrent human tumors. Here, we investigated the ability of photodynamic therapy, using Photofrin, to inhibit growth of R3230AC mammary adenocarcinomas when tumors were treated as original implants and again as lesions recurring at the initial treatment site. The results demonstrate that both initial implants and lesions recurring after the first photodynamic treatment respond similarly to the same photodynamic therapy protocol, with mean tumor volume doubling times of approximately 11 days in both cases. Cells cultured from original tumor implants or tumors that recurred after photodynamic treatment accumulate equivalent amounts of [14C]polyhematoporphyrin. Single cell suspensions prepared from either original or recurrent tumors from animals administered 5 mg/kg Photofrin and exposed to light in vitro displayed comparable phototoxicity. Additionally, examination of tumors by light microscopy revealed no morphological differences between the original tumor implants and the recurrent lesions. Taken together, these data indicate that lesions which recurred at the site of the initial photodynamic treatment were not resistant to a second identical course of photodynamic therapy.
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Neoplasias Mamarias Experimentales/tratamiento farmacológico , Fotoquimioterapia , Animales , Éter de Dihematoporfirina/uso terapéutico , Femenino , Neoplasias Mamarias Experimentales/patología , Ratas , Ratas Endogámicas F344 , Recurrencia , Células Tumorales CultivadasRESUMEN
From a structurally distinct set of o-substituted tetraphenylporphyrins, the picket fence porphyrin (PFP), 3,1-meso-tetrakis(o-propionamidophenyl)porphyrin (3,1-TPro) has been selected as a potential candidate for use in the photodynamic therapy (PDT) of cancer. In this report, the time-dependent tissue distribution of 14C-labeled 3,1-TPro is described along with the results of various treatment regimens. The tissue distribution of radiolabeled 3,1-TPro is comparable to that of other porphyrin photosensitizers with the advantage of being most effective at 4 h and being cleared rapidly from most tissues. The results of the various treatment regimen experiments, as well as other studies, indicate that the 3,1-TPro mechanism of action is similar to that of other photosensitizers, but may include some minor differences. The conclusion is that 3,1-TPro and other PFP offer a class of effective photosensitizers that may be exploited for their structural versatility, straightforward synthesis leading to a compound of high purity and known structure, and stability (both in terms of shelf-life and in vivo metabolism) as potential candidates for PDT.