Publications by authors named "Miguel Plaza"

Inflammatory bowel disease is a gut-brain axis disorder that comprises chronic inflammatory conditions affecting the gastrointestinal tract, where alterations in the mood of patients are common. Gut-brain axis is a bidirectional communication that link gut and brain. The close association between inflammatory bowel disease and neuroinflammation has far-reaching implications, as is increasingly recognized as a contributing factor to neuropsychiatric and neurodegenerative diseases.

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Functional gastrointestinal diseases (FGID) are worldwide prevalent conditions. Pharmacological treatments can be ineffective, leading the population to turn to herbal or traditional remedies. (L.

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Helichrysum stoechas (L.) Moench (H. stoechas) is a medicinal plant traditionally used in the Iberian Peninsula to treat different disorders such as arterial hypertension.

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Serotonin (5-HT) is an essential gastrointestinal modulator whose effects regulate the intestinal physiology. 5-HT effects depend on extracellular 5-HT bioavailability, which is controlled by the serotonin transporter (SERT) expressed in both the apical and basolateral membranes of enterocytes. SERT is a critical target for regulating 5-HT levels and consequently, modulating the intestinal physiology.

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Introduction: Jasonia glutinosa is an endemic plant species of the Iberian Peninsula and Southern France traditionally used in infusions as a spasmolytic; this plant is also known as "té de roca" (rock tea) but there is no scientific evidence about the effects of this plant.

Aim: To evaluate the spasmolytic effect of rock tea.

Methods: We have studied the in vitro effect of a rock tea extract on rat duodenum spontaneous contractions and the in vivo effect on mice gastrointestinal transit.

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Flavonoids are known to relax precontracted intestinal smooth muscle and delay intestinal transit or intestinal peristalsis. The aim of this study was to determine the effects of genistein and quercetin on spontaneous contractions of rabbit duodenum in vitro in an organ bath. Genistein and quercetin (0.

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Background: Lipopolysaccharide decreases intestinal contractility and induces the production of cytokines, which play an important role in the pathogenesis of sepsis.

Aim: The objective of the present study was to examine the role of Toll-like receptor 4, IκB kinase, and the proteasome in the intestinal alterations induced by lipopolysaccharide.

Methods: Sepsis was induced in rabbits by intravenous injection of lipopolysaccharide.

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The aim of this work is to propose an HPLC method for analysing major steviol glycosides as well as to optimise the extraction and clarification conditions for obtaining these compounds. Toward this aim, standards of stevioside and rebaudioside A with purities ⩾99.0%, commercial samples from different companies and Stevia rebaudiana Bertoni leaves from Paraguay supplied by Insobol, S.

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Background: several diseases such as sepsis can affect the ileum. Lipopolysaccharide (LPS), an endotoxin present in the cell wall of gram negative bacteria, is a causative agent of sepsis.

Objectives: the aims of this study were: a) to investigate the role of mitogen activated protein kinases (MAPKs) in the effect of LPS on the acetylcholine-induced contractions of rabbit ileum; and b) to study the localization of MAPKs in the ileum.

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Alterations in intestinal motility are one of the features of sepsis induced by lipopolysaccharide (LPS). This study investigated the role of the nuclear transcription factor κB (NF-κB) in the LPS-induced duodenal contractility alterations, generation of reactive oxygen species (ROS) and production of cytokines in rabbit duodenum. Rabbits were treated with saline, LPS, sulfasalazine + LPS, pyrrolidinedithiocarbamate (PDTC) + LPS or RO 106-9920 + LPS.

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Trolox is a hydrophilic analogue of vitamin E and a free radical scavenger. Ethanol diminishes the amplitude of spontaneous contractions and acetylcholine (ACh)-induced contractions in rabbit duodenum. The aim of this work was to study the effect of Trolox on the alterations induced by ethanol on contractility and lipid peroxidation in the duodenum.

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Objectives: Lipopolysaccharide (LPS) has been shown to alter intestinal contractility. Toll-like receptor 4 (TLR4), K(+) channels and mitogen-activated protein kinases (MAPKs) have been proposed to be involved in the mechanism of action of LPS. The aim of this study was to determine the role of TLR4, K(+) channels and MAPKs (p38, JNK and MEK1/2) in the local effect of LPS on the acetylcholine (ACh)-induced contractions in rabbit small intestine in vitro.

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Aim: To study the role of the tachykinin receptors in spontaneous contractions of longitudinal and circular smooth muscle from rabbit small intestine and to determine the mechanism of action of Substance P (SP).

Methods: Rabbit duodenum, jejunum and ileum segments were prepared. The spontaneous contractions of longitudinal and circular smooth muscle were recorded using a computer via an isometric force transducer.

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Background: Lipopolysaccharide (LPS) is a causative agent of sepsis. Many alterations, such as intestinal motility disturbances, have been attributed to LPS.

Aims: Here we investigated the role of c-Jun NH(2)-terminal kinases (JNK) in the effect of LPS on intestinal motility, the oxidative stress status and the cyclooxygenese-2 (COX-2) expression.

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The mediators of the pathophysiological symptoms of septic shock are not completely understood. The intracellular signalling mechanisms of lipopolysaccharide (LPS)-induced effects need further investigation. This study investigates (1) the role of COX-2 in the effect of LPS on (a) the KCl, acetylcholine and prostaglandin E₂-induced contractions of rabbit duodenum and (b) the oxidative stress status in plasma and intestine and (2) the relationship between p38 MAPK and COX-2 expression in rabbit duodenum.

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Background And Objectives: Anesthesiologists became more concerned about ensuring patient safety by a greater emphasis on outcome, quality patient care both in operation theatre and elsewhere in hospital. In the clinical practice, there is no aspect of Anesthesia that occupies a more important place in the safe management of the patients than the accurate drug administration. Medication errors represent a small part of anesthesia problems but still have potential for serious morbidity and legal consequences.

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The effects of PGE(2) on longitudinal smooth muscle, the intracellular mechanisms involved, and the localization of EP receptors were investigated in rabbit small intestine. PGE(2) evoked contractions in small intestine that were reduced by tetrodotoxin and hexamethonium. 17-Phenyl trinor PGE(2), sulprostone, misoprostol and 16,16-dimethyl PGE(2) evoked contractions.

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Children with diaphragm dysfunction may be unable to maintain adequate ventilation. Accurate diagnosis is important, but can only be achieved using an appropriate test and reference range. The aim of this study, therefore, was to measure diaphragm contractility and examine the influence of age and maturation, using magnetic phrenic nerve stimulation in healthy children.

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Purpose: We have evaluated randomized controlled trials of the administration of clonidine, neostigmine, steroids and non-steroidal anti-inflammatory agents intra-articularly as adjuvants to local anesthetic drugs after arthroscopic knee surgery.

Methods: Twenty-five studies were reviewed using specific inclusion criteria and, accordingly, included in the final assessment. These studies were assessed for pain scores, total analgesic consumption and time to first analgesic request to determine a possible peripheral effect, as opposed to possible systemic effects of an adjuvant administered intra-articularly.

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Background And Objectives: Tourniquet pain during intravenous regional anesthesia (IVRA) of the upper limb is common and can limit tourniquet inflation time. We hypothesize that a forearm rescue cuff is better tolerated than the traditional rescue cuff of a double-cuff tourniquet.

Methods: After Institutional Review Board (IRB) approval and informed consent, 10 healthy unmedicated volunteers took part in a prospective, randomized, cross-over study.

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