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1.
Protoplasma ; 258(6): 1307-1321, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34170416

RESUMEN

The recently described red alga Tsunamia transpacifica (Stylonematophyceae) was previously isolated from plastic drift found at the pacific coast, but the natural habitat remains unknown. Here, we investigate ultrastructural details and the low molecular weight soluble carbohydrate composition to get further insight into the adaptation to this uncommon habitat. By means of high pressure freeze fixation, followed by freeze substitution, we could detect an up to 2-µm-thick cell wall surrounded by a distinct layer of extracellular polymeric substances (EPS), likely responsible for the adhering capacities of Tsunamia. The central position of the nucleus and multilobed parietal chloroplast, already observed by light microscopy, could be confirmed. The ultrastructure revealed large electron-dense bodies (EB) in the central cytoplasm, likely resembling degradation products of the chloroplast. Interestingly, these structures contained phosphorous and cobalt, and iron was found in smaller rounded electron-dense bodies by electron energy loss spectroscopy (EELS). Accumulation of these elements suggests a high biosorption activity of Tsunamia. Liquid chromatography-mass spectrometry (LC-MS) data showed the presence of two heterosides (floridoside and digeneaside) together with the polyol sorbitol, which are known as organic osmolytes and compatible solutes. Taken together, these are the first observations on ultrastructural details, element storage and accumulation of protective compounds are contributing to our understanding of the ultrastructural and osmotic solute basis for the ability of Tsunamia to thrive on plastic surfaces.


Asunto(s)
Plásticos , Rhodophyta , Ecosistema , Peso Molecular , Fósforo
2.
Ther Adv Med Oncol ; 12: 1758835920963925, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33149768

RESUMEN

AIM: To compare the efficacy, safety, and tolerability of abemaciclib plus endocrine therapy (ET) versus ET alone in postmenopausal women with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC) from China, Brazil, India, and South Africa. METHODS: This randomized, double-blind, phase III study was conducted between 9 December 2016 and 29 March 2019. Postmenopausal women with HR-positive, HER2-negative ABC with no prior systemic therapy in an advanced setting (cohort A) or progression on prior ET (cohort B) received abemaciclib (150 mg twice daily) or placebo plus: anastrozole (1 mg/day) or letrozole (2.5 mg/day) (cohort A) or fulvestrant (500 mg per label) (cohort B). The primary endpoint was progression-free survival (PFS) in cohort A, analyzed using the stratified log-rank test. Secondary endpoints were PFS in cohort B (key secondary endpoint), objective response rate (ORR), and safety. This interim analysis was planned after 119 PFS events in cohort A. RESULTS: In cohort A, 207 patients were randomly assigned to the abemaciclib arm and 99 to the placebo arm. Abemaciclib significantly improved PFS versus placebo (median: not reached versus 14.7 months; hazard ratio 0.499; 95% confidence intervals (CI) 0.346-0.719; p = 0.0001). ORR was 65.9% in the abemaciclib arm and 36.1% in the placebo arm (p < 0.0001, measurable disease population). In cohort B, 104 patients were randomly assigned to the abemaciclib arm and 53 to the placebo arm. Abemaciclib significantly improved PFS versus placebo (median: 11.5 versus 5.6 months; hazard ratio 0.376; 95% CI 0.240-0.588; p < 0.0001). ORR was 50.0% in the abemaciclib arm and 10.5% in the placebo arm (p < 0.0001, measurable disease population). The most frequent grade ⩾3 adverse events in the abemaciclib arms were neutropenia, leukopenia, and anemia (both cohorts), and lymphocytopenia (cohort B). CONCLUSION: The addition of abemaciclib to ET demonstrated significant and clinically meaningful improvement in PFS and ORR, without new safety signals observed in this population.Trial Registration: ClinicalTrials.gov identifier: NCT02763566.

3.
Adv Med Sci ; 64(2): 315-323, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30978662

RESUMEN

The endoplasmic reticulum (ER) is the site of synthesis and folding of membrane and secretory proteins. The fraction of protein passing through the ER represents a large proportion of the total protein in the cell. Protein folding, glycosylation, sorting and transport are essential tasks of the ER and a compromised ER folding network has been recognized to be a key component in the disease pathogenicity of common neurodegenerative, metabolic and malignant diseases. On the other hand, the ER protein folding machinery also holds significant potential for therapeutic interventions. Many causes can lead to ER stress. A disturbed calcium homeostasis, the generation of reactive oxygen species (ROS) and a persistent overload of misfolded proteins within the ER can drive the course of adisease. In this review the role of ER-stress in diseases of the liver and pancreas will be examined using pancreatitis and Wilson´s disease as examples. Potential therapeutic targets in ER-stress pathways will also be discussed.


Asunto(s)
Estrés del Retículo Endoplásmico/fisiología , Hígado/metabolismo , Páncreas/metabolismo , Animales , Humanos , Pliegue de Proteína , Respuesta de Proteína Desplegada/fisiología
4.
Aquat Toxicol ; 208: 47-61, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30610964

RESUMEN

Biologically active compounds from pharmaceuticals cause concern due to their common occurrence in water and sediments of urbanized coasts and potential threat to marine organisms. Atorvastatin (ATO), a globally prescribed drug, is environmentally stable and bioavailable to marine organisms; however, the physiological and toxic effects of this drug on ecologically important coastal species are yet to be elucidated. We studied the effect of ATO (˜1.2 µg L-1) on bioenergetics (including whole-organism and mitochondrial respiration, as well as tissue energy reserves and mRNA expression of genes involved in mitochondrial biogenesis and fatty acid metabolism in the gills and the digestive gland) of a keystone bivalve Mytulis edulis (the blue mussel) from the Baltic Sea. Xenobiotic detoxification systems including activity and mRNA expression of P-glycoprotein, and Phase I and II biotransformation enzymes (cytochrome P450 monooxygenase CYP1A and glutathione transferase, GST) were also assessed in the gill and digestive gland of the mussels. Exposure to ATO caused rapid uptake and biotransformation of the drug by the mussels. Standard metabolic rate of ATO-exposed mussels increased by 56% indicating higher maintenance costs, yet no changes were detected in the respiratory capacity of isolated mitochondria. ATO exposure led to ˜60% decrease in the lysosomal membrane stability of hemocytes and ˜3-fold decrease in the whole-organism P-glycoprotein-driven and diffusional efflux of xenobiotics indicating altered membrane properties. The digestive gland was a major target of ATO toxicity in the mussels. Exposure of mussels to ATO led to depletion of lipid, carbohydrate and protein pools, and suppressed transcription of key enzymes involved in mitochondrial biogenesis (peroxisome proliferator-activated receptor gamma coactivator 1-alpha PGC-1α) and fatty acid metabolism (acetyl-CoA carboxylase and CYP4Y1) in the digestive gland. No bioenergetic disturbances were observed in the gills of ATO-exposed mussels, and elevated GST activity indicated enhanced ATO detoxification in this tissue. These data demonstrate that ATO can act as a metabolic disruptor and chemosensitizer in keystone marine bivalves and warrant further investigations of statins as emerging pollutants of concern in coastal marine ecosystems.


Asunto(s)
Organismos Acuáticos/efectos de los fármacos , Atorvastatina/toxicidad , Metabolismo Energético/efectos de los fármacos , Mytilus edulis/efectos de los fármacos , Mytilus edulis/metabolismo , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Animales , Atorvastatina/química , Biotransformación/efectos de los fármacos , Respiración de la Célula/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Hemocitos/efectos de los fármacos , Hemocitos/metabolismo , Inactivación Metabólica/efectos de los fármacos , Metaboloma/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mytilus edulis/genética , Consumo de Oxígeno/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Estrés Fisiológico/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad
5.
AMB Express ; 8(1): 66, 2018 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-29696483

RESUMEN

Aqueous two-phase systems (ATPS) occur by the mixture of two polymers or a polymer and an inorganic salt in water. It was shown that not only polymers but also ionic liquids in combination with inorganic cosmotrophic salts are able to build ATPS. Suitable for the formation of ionic liquid-based ATPS systems are hydrophilic water miscible ionic liquids. To understand the driving force for amino acid and peptide distribution in IL-ATPS at different pH values, the ionic liquid Ammoeng 110™ and K2HPO4 have been chosen as a test system. To quantify the concentration of amino acids and peptides in the different phases, liquid chromatography and mass spectrometry (LC-MS) technologies were used. Therefore the peptides and amino acids have been processed with EZ:faast™-Kit from Phenomenex for an easy and reliable quantification method even in complex sample matrices. Partitioning is a surface-dependent phenomenon, investigations were focused on surface-related amino acid respectively peptide properties such as charge and hydrophobicity. Only a very low dependence between the amino acids or peptides hydrophobicity and the partition coefficient was found. Nevertheless, the presented results show that electrostatic respectively ionic interactions between the ionic liquid and the amino acids or peptides have a strong impact on their partitioning behavior.

7.
Neonatology ; 93(3): 188-92, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17992018

RESUMEN

INTRODUCTION: Meconium aspiration produces airway obstruction and surfactant inhibition. Bronchoalveolar lavage (BAL) and surfactant replacement have been proposed as treatments for the syndrome. OBJECTIVE: To evaluate the effect of BAL with normal saline followed by a supplementary dose of surfactant in a piglet model of meconium aspiration syndrome. METHODS: 15 newborn piglets were used in the study. The animals were ventilated with fixed settings. After inhalation of 4 ml/kg of diluted meconium, the piglets were randomized into three groups: group I (n = 5) - tracheal aspiration without BAL; group II (n = 5) - BAL with normal saline (15 ml/kg), and group III (n = 5) - BAL with normal saline (15 ml/kg) followed by a supplementary dose of surfactant (Curosurf(R) 100 mg/kg). Arterial blood gas samples were obtained 30 min and 6 h after the inhalation of meconium. RESULTS: A significant increase of PaO(2 )values at 6 h after treatment was only observed in group III (from 51 +/- 13 to 189 +/- 115 mm Hg; p = 0.04). At this time, PaO(2) in group III was significantly higher compared to group II (189 +/- 115 and 37 +/- 11 mm Hg, respectively; p = 0.023) and showed a borderline significance when compared to group I (p = 0.066). CONCLUSION: BAL with normal saline followed by a supplementary dose of surfactant may improve oxygenation in an experimental piglet model of meconium aspiration syndrome.


Asunto(s)
Lavado Broncoalveolar/métodos , Síndrome de Aspiración de Meconio/terapia , Surfactantes Pulmonares/uso terapéutico , Animales , Animales Recién Nacidos , Análisis de los Gases de la Sangre , Modelos Animales de Enfermedad , Histocitoquímica , Humanos , Recién Nacido , Síndrome de Aspiración de Meconio/patología , Distribución Aleatoria , Porcinos
8.
Acta méd. (Porto Alegre) ; 26: 565-576, 2005.
Artículo en Portugués | LILACS | ID: lil-422629

RESUMEN

Os autores fazem uma revisão sobre o rastreamento, diagnóstico precoce e quimioprevenção do câncer colorretal, avaliando os métodos diagnósticos e o emprego de drogas em sua prevenção


Asunto(s)
Masculino , Femenino , Humanos , Quimioterapia Adyuvante , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/prevención & control , Neoplasias Colorrectales/tratamiento farmacológico
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