RESUMEN
Glycosylation processes are under high natural selection pressure, presumably because these can modulate resistance to infection. Here, we asked whether inactivation of the UDP-galactose:ß-galactoside-α1-3-galactosyltransferase (α1,3GT) gene, which ablated the expression of the Galα1-3Galß1-4GlcNAc-R (α-gal) glycan and allowed for the production of anti-α-gal antibodies (Abs) in humans, confers protection against Plasmodium spp. infection, the causative agent of malaria and a major driving force in human evolution. We demonstrate that both Plasmodium spp. and the human gut pathobiont E. coli O86:B7 express α-gal and that anti-α-gal Abs are associated with protection against malaria transmission in humans as well as in α1,3GT-deficient mice, which produce protective anti-α-gal Abs when colonized by E. coli O86:B7. Anti-α-gal Abs target Plasmodium sporozoites for complement-mediated cytotoxicity in the skin, immediately after inoculation by Anopheles mosquitoes. Vaccination against α-gal confers sterile protection against malaria in mice, suggesting that a similar approach may reduce malaria transmission in humans.
Asunto(s)
Escherichia coli/fisiología , Inmunoglobulina M/inmunología , Malaria Falciparum/inmunología , Malaria Falciparum/transmisión , Plasmodium/fisiología , Polisacáridos/inmunología , Adulto , Animales , Anopheles/parasitología , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Anticuerpos Antiprotozoarios/sangre , Anticuerpos Antiprotozoarios/inmunología , Autoantígenos/inmunología , Línea Celular Tumoral , Niño , Escherichia coli/clasificación , Escherichia coli/inmunología , Femenino , Galactosiltransferasas/genética , Galactosiltransferasas/metabolismo , Tracto Gastrointestinal/microbiología , Vida Libre de Gérmenes , Humanos , Inmunoglobulina M/sangre , Malaria Falciparum/microbiología , Malaria Falciparum/parasitología , Ratones , Plasmodium/clasificación , Plasmodium/crecimiento & desarrollo , Plasmodium/inmunología , Plasmodium falciparum/inmunología , Plasmodium falciparum/fisiología , Esporozoítos/inmunología , Receptor Toll-Like 9/agonistasRESUMEN
Accumulation of anthocyanins in the exocarp of red grapevine (Vitis vinifera) cultivars is one of several events that characterize the onset of grape berry ripening (véraison). Despite our thorough understanding of anthocyanin biosynthesis and regulation, little is known about the molecular aspects of their transport. The participation of ATP binding cassette (ABC) proteins in vacuolar anthocyanin transport has long been a matter of debate. Here, we present biochemical evidence that an ABC protein, ABCC1, localizes to the tonoplast and is involved in the transport of glucosylated anthocyanidins. ABCC1 is expressed in the exocarp throughout berry development and ripening, with a significant increase at véraison (i.e., the onset of ripening). Transport experiments using microsomes isolated from ABCC1-expressing yeast cells showed that ABCC1 transports malvidin 3-O-glucoside. The transport strictly depends on the presence of GSH, which is cotransported with the anthocyanins and is sensitive to inhibitors of ABC proteins. By exposing anthocyanin-producing grapevine root cultures to buthionine sulphoximine, which reduced GSH levels, a decrease in anthocyanin concentration is observed. In conclusion, we provide evidence that ABCC1 acts as an anthocyanin transporter that depends on GSH without the formation of an anthocyanin-GSH conjugate.
Asunto(s)
Antocianinas/metabolismo , Frutas/metabolismo , Glucósidos/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteínas de Plantas/metabolismo , Vitis/metabolismo , Secuencia de Aminoácidos , Antocianinas/química , Transporte Biológico , Clonación Molecular , ADN Complementario/química , ADN Complementario/genética , Frutas/genética , Frutas/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Glucósidos/química , Glutatión/metabolismo , Membranas Intracelulares/metabolismo , Datos de Secuencia Molecular , Estructura Molecular , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/clasificación , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Filogenia , Proteínas de Plantas/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Vacuolas/metabolismo , Vitis/genética , Vitis/crecimiento & desarrolloRESUMEN
Polyols are important metabolites that often function as carbon and energy sources and/or osmoprotective solutes in some plants. In grapevine, and in the grape berry in particular, the molecular aspects of polyol transport and metabolism and their physiological relevance are virtually unknown to date. Here, the biochemical function of a grapevine fruit mesocarp polyol transporter (VvPLT1) was characterized after its heterologous expression in yeast. This H(+)-dependent plasma membrane carrier transports mannitol (K m=5.4mM) and sorbitol (K m=9.5mM) over a broad range of polyols and monosaccharides. Water-deficit stress triggered an increase in the expression of VvPLT1 at the fully mature stage, allowing increased polyol uptake into pulp cells. Plant polyol dehydrogenases are oxireductases that reversibly oxidize polyols into monosaccharides. Mannitol catabolism in grape cells (K m=30.1mM mannitol) and mature berry mesocarps (K m=79mM) was, like sorbitol dehydrogenase activity, strongly inhibited (50-75%) by water-deficit stress. Simultaneously, fructose reduction into polyols via mannitol and sorbitol dehydrogenases was stimulated, contributing to their higher intracellular concentrations in water-deficit stress. Accordingly, the concentrations of mannitol, sorbitol, galactinol, myo-inositol, and dulcitol were significantly higher in berry mesocarps from water-deficit-stressed Tempranillo grapevines. Metabolomic profiling of the berry pulp by GC-TOF-MS also revealed many other changes in its composition induced by water deficit. The impact of polyols on grape berry composition and plant response to water deficit stress, via modifications in polyol transport and metabolism, was analysed by integrating metabolomics with transcriptional analysis and biochemical approaches.
Asunto(s)
Metabolismo de los Hidratos de Carbono , Frutas/metabolismo , Osmorregulación , Estrés Fisiológico/fisiología , Vitis/metabolismo , Agua/metabolismo , Secuencia de Aminoácidos , Transporte Biológico Activo , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Alineación de Secuencia , Vitis/genéticaRESUMEN
Vitis vinifera L. represents an economically important fruit species. Grape and wine flavour is made from a complex set of compounds. The acidity of berries is a major parameter in determining grape berry quality for wine making and fruit consumption. Despite the importance of malic and tartaric acid (TA) storage and transport for grape berry acidity, no vacuolar transporter for malate or tartrate has been identified so far. Some members of the aluminium-activated malate transporter (ALMT) anion channel family from Arabidopsis thaliana have been shown to be involved in mediating malate fluxes across the tonoplast. Therefore, we hypothesised that a homologue of these channels could have a similar role in V. vinifera grape berries. We identified homologues of the Arabidopsis vacuolar anion channel AtALMT9 through a TBLASTX search on the V. vinifera genome database. We cloned the closest homologue of AtALMT9 from grape berry cDNA and designated it VvALMT9. The expression profile revealed that VvALMT9 is constitutively expressed in berry mesocarp tissue and that its transcription level increases during fruit maturation. Moreover, we found that VvALMT9 is targeted to the vacuolar membrane. Using patch-clamp analysis, we could show that, besides malate, VvALMT9 mediates tartrate currents which are higher than in its Arabidopsis homologue. In summary, in the present study we provide evidence that VvALMT9 is a vacuolar malate channel expressed in grape berries. Interestingly, in V. vinifera, a tartrate-producing plant, the permeability of the channel is apparently adjusted to TA.
Asunto(s)
Regulación de la Expresión Génica de las Plantas , Malatos/metabolismo , Transportadores de Anión Orgánico/genética , Tartratos/metabolismo , Vitis/genética , Transporte Biológico , Clonación Molecular , ADN Complementario/genética , Frutas/genética , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Expresión Génica , Genes Reporteros , Transportadores de Anión Orgánico/metabolismo , Técnicas de Placa-Clamp , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Protoplastos , Proteínas Recombinantes de Fusión , Vacuolas/metabolismo , Vitis/citología , Vitis/crecimiento & desarrollo , Vitis/metabolismoRESUMEN
Grape berries (Vitis vinifera L fruit) exhibit a double-sigmoid pattern of development that results from two successive periods of vacuolar swelling during which the nature of accumulated solutes changes significantly. Throughout the first period, called green or herbaceous stage, berries accumulate high levels of organic acids, mainly malate and tartrate. At the cellular level fruit acidity comprises both metabolism and vacuolar storage. Malic acid compartmentation is critical for optimal functioning of cytosolic enzymes. Therefore, the identification and characterization of the carriers involved in malate transport across sub-cellular compartments is of great importance. The decrease in acid content during grape berry ripening has been mainly associated to mitochondrial malate oxidation. However, no Vitis vinifera mitochondrial carrier involved in malate transport has been reported to date. Here we describe the identification of three V. vinifera mitochondrial dicarboxylate/tricarboxylate carriers (VvDTC1-3) putatively involved in mitochondrial malate, citrate and other di/tricarboxylates transport. The three VvDTCs are very similar, sharing a percentage of identical residues of at least 83 %. Expression analysis of the encoding VvDTC genes in grape berries shows that they are differentially regulated exhibiting a developmental pattern of expression. The simultaneous high expression of both VvDTC2 and VvDTC3 in grape berry mesocarp close to the onset of ripening suggests that these carriers might be involved in the transport of malate into mitochondria.
Asunto(s)
Proteínas Portadoras/metabolismo , Transportadores de Ácidos Dicarboxílicos/metabolismo , Frutas/metabolismo , Mitocondrias/metabolismo , Vitis/metabolismo , Secuencia de Aminoácidos , Proteínas Portadoras/química , Clonación Molecular , Transportadores de Ácidos Dicarboxílicos/química , Escherichia coli/metabolismo , Frutas/enzimología , Frutas/genética , Frutas/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Cinética , Malatos/metabolismo , Datos de Secuencia Molecular , Filogenia , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Especificidad por Sustrato , Vitis/enzimología , Vitis/genética , Vitis/crecimiento & desarrolloRESUMEN
Introduction: Anorectal pain is a symptom with a negative impact on quality of life and it can sometimes develop into a chronic pain syndrome. Structural anorectal pain is treated according to the underlying pathology. In situations of chronic post-surgical pain that is refractory to conventional therapeutic approaches, percutaneous tibial nerve stimulation (PTNS) is an option. PTNS is a neurostimulation technique used in the treatment of lower urinary tract dysfunction. There has been increasing evidence of its benefits for improving other conditions, such as chronic pelvic pain (CPP) and faecal incontinence (FI). Case Presentation: We report a case of a 45-year-old woman with chronic post-surgical anorectal pain (CPAP) treated with PTNS. The patient reported a consistent and dramatic decrease in both the frequency and intensity of pain, assessed by the Brief Pain Inventory (BPI). A decrease in the pain interference with mood, normal work, and walking/mobility was also noted, as evaluated by BPI and EQ-5D-3L questionnaires. Discussion: Neuromodulation treatments have been reported as effective for anorectal pain, but reports on the use of PTNS are rare. The tibial nerve is easily accessible and provides an optimal site for neurostimulation without the need of an operating room or anaesthesia. The overall improvement observed in this case of chronic anorectal pain suggests a potential new area of research for PTNS.
Introdução: A dor anorectal é um sintoma com um impacto negativo na qualidade de vida, podendo, por vezes, desenvolver-se numa síndrome de dor crónica. A dor ano rectal de etiologia estrutural trata-se de acordo com a patologia subjacente. No entanto, em situações de dor crónica pós-cirúrgica refratária a abordagens terapêuticas convencionais, a estimulação percutânea do nervo tibial (percutaneous tibial nerve stimulation − PTNS) é uma opção de tratamento. A PTNS é uma técnica de neuroestimulação, estando descritos benefícios da sua aplicação no tratamento da urgência, frequência, incontinência e retenção urinária. Evidência crescente mostra, ainda, resultados promissores noutras condições, como a dor crónica pélvica e a incontinência fecal. Caso Clínico: Descrevemos um caso de uma mulher de 45 anos, com dor crónica anorectal pós-cirúrgica tratada com PTNS. Ao longo do período de seguimento, a doente reportou uma diminuição consistente e significativa na frequência e na intensidade da dor, tal como avaliado pelo Brief Pain Inventory (BPI). Adicionalmente, foi notória uma melhoria significativa de parâmetros relacionados com a qualidade de vida, avaliados pelos questionários BPI e EQ-5D-3L. Discussão: A evidência atual mostra que técnicas baseadas em neuromodulação têm sido eficazes no tratamento da dor anorectal, apesar dos estudos com PTNS ainda serem escassos. O nervo tibial é uma estrutura facilmente acessível e constitui um local óptimo para aplicação de neuroestimulação. A PTNS é uma opção terapêutica pouco invasiva, que não necessita de idas ao bloco operatório, nem de apoio de anestesia. O benefício observado do uso da PTNS neste caso sugere uma nova área de estudo e de potencial aplicabilidade para a técnica.
RESUMEN
Pneumocephalus is a rare consequence of epidural anesthesia, which may occur following inadvertent or unidentified dural puncture when the loss of resistance to air technique is applied to identify the epidural space. Headache is the most common symptom presented in this condition, usually with sudden onset. This case report describes an unusual presentation of diffuse pneumocephalus after an unidentified dural puncture. The patient (male, 67 years old) was submitted to epidural catheter placement for the treatment of acute exacerbation of ischemic chronic pain using loss of resistance to air technique. No cerebrospinal fluid or blood flashback was observed after needle withdrawal. Shortly after the intervention, the patient presented symptoms of lethargy, apathy, and hypophonia, which are not commonly associated with pneumocephalus. No motor or sensory deficits were detected. Cranial computed tomography showed air in the frontal horn of the left ventricle, subarachnoid space at interhemispheric fissure and basal cisterns, confirming the diagnosis of diffuse pneumocephalus. The patient remained under vigilance with oxygen therapy and the epidural catheter left in place. After 24 hours, cranial computed tomography showed air in the temporal and frontal horns of the left ventricle, with no air in the subarachnoid space. The patient presented no neurological signs or symptoms at this time. Although headache is the most common symptom presented in reported cases of pneumocephalus, this case shows the need for the clinician to be aware of other signs and symptoms that may be indicative of this condition, in order to properly diagnose and treat these patients.Key words: Pneumocephalus, continuous epidural analgesia, ischemic chronic pain, loss-of-resistance to air technique, dural puncture, headache, unusual presentation.
Asunto(s)
Analgesia Epidural/efectos adversos , Neumocéfalo/etiología , Anciano , Anestesia Epidural , Espacio Epidural , Humanos , Masculino , Punciones/efectos adversosRESUMEN
Fusarium oxysporum f. sp. melonis is a highly specialized fungus that attacks the root system of melon (Cucumis melo L.). In this work the presence of a class III chitinase was examined by immunological techniques in the root and stem base of a susceptible (cv. Galia) and a resistant (cv. Bredor) melon during the infection process. By immunolocalization it was not possible to detect the constitutive presence of class III chitinase in any of the cultivars. However, the immunolabelling appeared in the root tissues of both cultivars as a consequence of wounding and of infection by F. oxysporum f. sp. melonis. Distinct patterns of chitinase detection were observed in the roots of the two cultivars as the infection progressed. Furthermore, by western blotting distinct class III chitinase isoforms were detected, which responded differently to the F. oxysporum f. sp. melonis infection. Our results strongly indicate that a relationship exists between class III chitinase and melon resistance to Fusarium infection, and that the resistance is associated with certain isoforms of this enzyme.
Asunto(s)
Quitinasas/análisis , Cucumis melo/enzimología , Fusarium/fisiología , Cucumis melo/microbiología , Técnicas para Inmunoenzimas , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/análisis , Raíces de Plantas/enzimología , Raíces de Plantas/microbiologíaRESUMEN
A retrospective analyses of patients submitted to surgery on a day basis was made through our database. The goal of the study was to identify risk factors of postoperative vomiting associated to day surgery. 2115 patients operated between January 2003 and November 2004 on our day surgery unit were included. 70 patients (3,3%) suffered at least on episode of postoperative vomiting. Several factors were analysed: age, sex, surgical speciality, ASA physical status, anaesthetic technique and the duration of anesthesia. Chi-Square Test was used for testing each factor individually. Differences were considered significant when p <0,05. Logistic regression was then used to identify the multivariate association strength of these factors. The female sex (Odds ratio =4,94) and the duration of anesthesia when longer than 180 minutes (Odds ratio =8,13), had been associated to a higher incidence of postoperative vomiting, while loco-regional technique (Odds ratio = 0,15) and sedation with local anaesthesia (Odds ratio =0,09) had been associated with a lower incidence. Authors evidence the importance of the identification of postoperative vomiting risk factors that will allow us to establish better guidelines on postoperative nausea and vomiting prophylaxis in these patients and to improve the quality of our clinical care and the satisfaction of our patients.
Asunto(s)
Procedimientos Quirúrgicos Ambulatorios , Náusea y Vómito Posoperatorios/epidemiología , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Adulto JovenRESUMEN
According to previous reports, flavonoids and nutraceuticals correct defective electrolyte transport in cystic fibrosis (CF) airways. Traditional medicinal plants from China and Thailand contain phytoflavonoids and other bioactive compounds. We examined herbal extracts of the common Thai medicinal euphorbiaceous plant Phyllanthus acidus for their potential effects on epithelial transport. Functional assays by Ussing chamber, patch-clamping, double-electrode voltage-clamp and Ca2+ imaging demonstrate activation of Cl- secretion and inhibition of Na+ absorption by P. acidus. No cytotoxic effects of P. acidus could be detected. Mucosal application of P. acidus to native mouse trachea suggested transient and steady-state activation of Cl- secretion by increasing both intracellular Ca2+ and cAMP. These effects were mimicked by a mix of the isolated components adenosine, kaempferol, and hypogallic acid. Additional experiments in human airway cells and CF transmembrane conductance regulator (CFTR)-expressing BHK cells and Xenopus laevis oocytes confirm the results obtained in native tissues. Cl- secretion was also induced in tracheas of CF mice homozygous for Phe508del-CFTR and in Phe508del-CFTR homozygous human airway epithelial cells. Taken together, P. acidus corrects defective electrolyte transport in CF airways by parallel mechanisms including 1) increasing the intracellular levels of second messengers cAMP and Ca2+, thereby activating Ca2+-dependent Cl- channels and residual CFTR-Cl- conductance; 2) stimulating basolateral K+ channels; 3) redistributing cellular localization of CFTR; 4) directly activating CFTR; and 5) inhibiting ENaC through activation of CFTR. These combinatorial effects on epithelial transport may provide a novel complementary nutraceutical treatment for the CF lung disease.