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Gastrojejunostomy is the principal method of palliation for unresectable malignant gastric outlet obstructions (GOO). Gastrojejunostomy was traditionally performed as a surgical procedure with an open approach butrecently, notable progress in the development of minimally invasive procedures such as laparoscopic gastrojejunostomies have emerged. Additionally, advancements in endoscopic techniques, including endoscopic stenting (ES) and endoscopic ultrasound-guided gastroenterostomy (EUS-GE), are becoming more prominent. ES involves the placement of self-expandable metal stents (SEMS) to restore luminal patency. ES is commonly the first choice for patients deemed unfit for surgery or at high surgical risk. However, although ES leads to rapid improvement of symptoms, it carries limitations like higher stent dysfunction rates and the need for frequent re-interventions. Recently, EUS-GE has emerged as a potential alternative, combining the minimally invasive nature of the endoscopic approach with the long-lasting effects of a gastrojejunostomy. Having reviewed the advantages and disadvantages of these different techniques, this article aims to provide a comprehensive review regarding the management of unresectable malignant GOO.
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Obstrucción de la Salida Gástrica , Obstrucción de la Salida Gástrica/cirugía , Obstrucción de la Salida Gástrica/etiología , Humanos , Cuidados Paliativos/métodos , Derivación Gástrica/métodos , Stents , Endosonografía/métodos , Neoplasias Gástricas/complicaciones , Neoplasias Gástricas/cirugíaRESUMEN
OBJECTIVES: Endoscopic retrograde cholangiopancreatography (ERCP) represents the gold standard for jaundice palliation in patients with distal malignant biliary obstruction (DMBO). Biliary drainage using electrocautery lumen apposing metal stent (EC-LAMS) is currently a well-established procedure when ERCP fails. In a palliative setting the endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) could represent an easy and valid option. We performed a prospective study with a new EC-LAMS with the primary aim to assess the clinical success rate of EUS-GBD as a first-line approach to the palliation of DMBO. METHODS: In all, 37 consecutive patients undergoing EUS-GBD with a new EC-LAMS were prospectively enrolled. Clinical success was defined as bilirubin level decrease >15% within 24 h and >50% within 14 days after EC-LAMS placement. RESULTS: The mean age was 73.5 ± 10.8 years; there were 17 male patients (45.9%). EC-LAMS placement was technically feasible in all patients (100%) and the clinical success rate was 100%. Four patients (10.8%) experienced adverse events, one bleeding, one food impaction, and two cystic duct obstructions because of disease progression. No stent-related deaths were observed. The mean hospitalization was 7.7 ± 3.4 days. Median overall survival was 4 months (95% confidence interval 1-8). CONCLUSION: Endoscopic ultrasound-guided gallbladder drainage with the new EC-LAMS is a valid option in palliative endoscopic biliary drainage as a first-step approach in low survival patients with malignant jaundice unfit for surgery. A smaller diameter EC-LAMS should be preferred, particularly if the drainage is performed through the stomach, to avoid potential food impaction, which could result in stent dysfunction.
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Colestasis , Ictericia , Humanos , Masculino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Vesícula Biliar , Estudios Prospectivos , Colestasis/diagnóstico por imagen , Colestasis/etiología , Colestasis/cirugía , Endosonografía/métodos , Ictericia/complicaciones , Drenaje/métodos , Stents/efectos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Ultrasonografía Intervencional/métodosRESUMEN
Endoscopic retrograde cholangiopancreatography (ERCP) is considered the preferred method for managing biliary obstructions. However, the prevalence of surgically modified anatomies often poses challenges, making the standard side-viewing duodenoscope unable to reach the papilla in most cases. The increasing instances of surgically altered anatomies (SAAs) result from higher rates of bariatric procedures and surgical interventions for pancreatic malignancies. Conventional ERCP with a side-viewing endoscope remains effective when there is continuity between the stomach and duodenum. Nonetheless, percutaneous transhepatic biliary drainage (PTBD) or surgery has historically been used as an alternative for biliary drainage in malignant or benign conditions. The evolving landscape has seen various endoscopic approaches tailored to anatomical variations. Innovative methodologies such as cap-assisted forward-viewing endoscopy and enteroscopy have enabled the performance of ERCP. Despite their utilization, procedural complexities, prolonged durations, and accessibility challenges have emerged. As a result, there is a growing interest in novel enteroscopy and endoscopic ultrasound (EUS) techniques to ensure the overall success of endoscopic biliary drainage. Notably, EUS has revolutionized this domain, particularly through several techniques detailed in the review. The rendezvous approach has been pivotal in this field. The antegrade approach, involving biliary tree puncturing, allows for the validation and treatment of strictures in an antegrade fashion. The EUS-transmural approach involves connecting a tract of the biliary system with the GI tract lumen. Moreover, the EUS-directed transgastric ERCP (EDGE) procedure, combining EUS and ERCP, presents a promising solution after gastric bypass. These advancements hold promise for expanding the horizons of comprehensive and successful biliary drainage interventions, laying the groundwork for further advancements in endoscopic procedures.
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Inflammatory bowel diseases (IBDs) are chronic, relapsing inflammatory disorders of the gastrointestinal tract, frequently associated with extraintestinal manifestations (EIMs) that can severely affect IBD patients' quality of life, sometimes even becoming life-threatening. Respiratory diseases have always been considered a rare and subsequently neglected extraintestinal manifestations of IBD. However, increasing evidence has demonstrated that respiratory involvement is frequent in IBD patients, even in the absence of respiratory symptoms. Airway inflammation is the most common milieu of IBD-related involvement, with bronchiectasis being the most common manifestation. Furthermore, significant differences in prevalence and types of involvement are present between Crohn's disease and ulcerative colitis. The same embryological origin of respiratory and gastrointestinal tissue, in addition to exposure to common antigens and cytokine networks, may all play a potential role in the respiratory involvement. Furthermore, other causes such as drug-related toxicity and infections must always be considered. This article aims at reviewing the current evidence on the association between IBD and respiratory diseases. The purpose is to raise awareness of respiratory manifestation among IBD specialists and emphasize the need for identifying respiratory diseases in early stages to promptly treat these conditions, avoid worsening morbidity, and prevent lung damage.
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This narrative review provides an overview of the application of endoscopic ultrasound-guided biliary drainage (EUS-BD), including EUS-guided gallbladder drainage (EUS-GBD), for the treatment of malignant biliary obstruction. EUS-BD has demonstrated excellent technical and clinical success rates, with lower rates of adverse events when compared with percutaneous trans-hepatic biliary drainage (PTBD). EUS-BD is currently the preferred alternative technique for biliary drainage (BD) in patients with distal malignant biliary obstruction (DMBO) after failed endoscopic retrograde cholangiopancreatography (ERCP). Particularly, this review will focus on EUS-BD performed with the use of lumen apposing metal stent (LAMS). The introduction of these innovative devices, followed by the advent of electrocautery-enhanced LAMS (EC-LAMS), gave the procedure a great technical implementation and a widespread application.
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Gastroesophageal reflux disease has a high incidence and prevalence in the general population. Clinical manifestations are heterogenous, and so is the response to medical treatment. Proton pump inhibitors are still the most common agents used to control reflux symptoms and for healing esophagitis, but they are not a one-size-fits-all solution for the disease. Patients with persistent troublesome symptoms despite medical therapy, those experiencing some adverse drug reaction, or those unwilling to take lifelong medications deserve valid alternatives. Anti-reflux Nissen fundoplication is an effective option, but the risk of adverse events has limited its spread. In recent years, advancements in therapeutic endoscopy have been made, and three major endoluminal alternatives are now available, including (1) the delivery of radiofrequency energy to the esophago-gastric junction, (2) transoral incisionless fundoplication (TIF), and (3) anti-reflux mucosal interventions (ARMI) based on mucosal resection (ARMS) and mucosal ablation (ARMA) techniques to remodel the cardia. Endoscopic techniques have shown interesting results, but their diffusion is still limited to expert endoscopists in tertiary centers. This review discusses the state of the art in the endoscopic approach to gastroesophageal reflux disease.
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Due to the high risk of morbidity and mortality associated with surgical resection in this tract, endoscopic resection (ER) has taken the place of surgical resection as the first line treatment for non-ampullary duodenal adenomas. However, due to the anatomical characteristics of this area, which enhance the risk of post-ER problems, ER in the duodenum is particularly difficult. Due to a lack of data, no ER technique for superficial non-ampullary duodenal epithelial tumours (SNADETs) has yet been backed by strong, high-quality evidence; yet, traditional hot snare-based techniques are still regarded as the standard treatment. Despite having a favourable efficiency profile, adverse events during duodenal hot snare polypectomy (HSP) and hot endoscopic mucosal resection, such as delayed bleeding and perforation, have been reported to be frequent. These events are primarily caused by electrocautery-induced damage. Thus, ER techniques with a better safety profile are needed to overcome these shortcomings. Cold snare polypectomy, which has already been shown as a safer, equally effective procedure compared to HSP for treatment of small colorectal polyps, is being increasingly evaluated as a potential therapeutic option for non-ampullary duodenal adenomas. The aim of this review is to report and discuss the early outcomes of the first experiences with cold snaring for SNADETs.
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Gastric outlet obstruction is a condition characterized by inadequate gastric emptying due to benign or malignant conditions inducing an inadequate oral intake. In recent years, a novel therapeutic treatment for this condition is given by the use of electrocautery lumen-apposing metal stents. In this case report, we want to present an example of a benign condition treated by endoscopic ultrasound-guided gastroenterostomy with the bi-flanged SpaxusTM stent (Taewoong Medical Co.) mounted on electrocautery catheter.
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Obstrucción de la Salida Gástrica , Ultrasonografía Intervencional , Humanos , Ultrasonografía Intervencional/efectos adversos , Endosonografía/efectos adversos , Gastroenterostomía/efectos adversos , Obstrucción de la Salida Gástrica/diagnóstico por imagen , Obstrucción de la Salida Gástrica/etiología , Obstrucción de la Salida Gástrica/cirugía , Stents/efectos adversosRESUMEN
Malignant biliary obstruction (MBO) is a challenging medical problem that often negatively impacts the patient's quality of life (QoL), postoperative complications, and survival rates. Endoscopic approaches to biliary drainage are generally performed by ERCP or, in selected cases, with a percutaneous transhepatic biliary drainage (PTBD). Recent advances in therapeutic endoscopic ultrasound (EUS) allow drainage where previous methods have failed. EUS has evolved from a purely diagnostic technique to one that allows a therapeutic approach in the event of ERCP failure in distal MBO. Moreover, the introduction of dedicated accessories and prostheses for EUS-guided transmural biliary drainage (EUS-BD) made these procedures more successful with regard to technical success, clinical outcomes and reduction of adverse events (AEs). Finally, lumen-apposing metal stents (LAMS) have improved the therapeutic role of the EUS. Subsequently, the electrocautery enhanced tip of the LAMS (EC-LAMS) allows a direct access of the delivery system to the target lumen, thereby simplifying and reducing the EUS-BD procedure time. EUS-BD using LAMS and EC-LAMS has proven effective and safe with a low rate of AEs. This review aims to evaluate biliary drainage techniques in malignant obstruction, focusing on the role of EUS biliary drainage by LAMS.
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Barrett's esophagus (BE) is a well-established risk factor for esophageal adenocarcinoma. It is recommended that patients have regular endoscopic surveillance, with the ultimate goal of detecting early-stage neoplastic lesions before they can progress to invasive carcinoma. Detection of both dysplasia or early adenocarcinoma permits curative endoscopic treatments, and with this aim, thorough endoscopic assessment is crucial and improves outcomes. The burden of missed neoplasia in BE is still far from being negligible, likely due to inappropriate endoscopic surveillance. Over the last two decades, advanced imaging techniques, moving from traditional dye-spray chromoendoscopy to more practical virtual chromoendoscopy technologies, have been introduced with the aim to enhance neoplasia detection in BE. As witnessed in other fields, artificial intelligence (AI) has revolutionized the field of diagnostic endoscopy and is set to cover a pivotal role in BE as well. The aim of this commentary is to comprehensively summarize present evidence, recent research advances, and future perspectives regarding advanced imaging technology and AI in BE; the combination of computer-aided diagnosis to a widespread adoption of advanced imaging technologies is eagerly awaited. It will also provide a useful step-by-step approach for performing high-quality endoscopy in BE, in order to increase the diagnostic yield of endoscopy in clinical practice.
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Adenocarcinoma , Esófago de Barrett , Neoplasias Esofágicas , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/patología , Inteligencia Artificial , Esófago de Barrett/diagnóstico por imagen , Esófago de Barrett/epidemiología , Endoscopía/métodos , Neoplasias Esofágicas/diagnóstico , Esofagoscopía/métodos , HumanosRESUMEN
Subjects affected by ulcerative colitis and Crohn's disease with colonic localization have an increased risk of colorectal cancer (CRC). Surveillance colonoscopy is recommended by international guidelines as it can detect early-stage CRC. Based on previous evidence, in 2015 the Surveillance for Colorectal Endoscopic Neoplasia Detection and Management in Inflammatory Bowel Disease Patients International Consensus indicated dye chromoendoscopy (DCE) as the most effective technique for detecting dysplasia. However, advances in endoscopic technology such as high-definition colonoscopes and dye-less virtual chromoendoscopy (VCE) may change future practice. In this review, we summarize the available evidence on CRC surveillance in IBD, focusing on the emerging role of high-definition white light endoscopy (HD-WLE) and VCE over the standard DCE, and the current role of random biopsies.
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OBJECTIVE: International guidelines recommend the introduction of sacubitril/valsartan (Entresto) in patients with heart failure (HF) and reduced ejection fraction (EF), who remain symptomatic, despite optimal uptitrated therapy. The purpose of the following analysis is to verify the real-life eligibility for sacubitril/valsartan in a population of patients suffering from chronic HF, regularly monitored in a single HF clinic and treated according to guideline-directed medical therapy (GDMT). METHODS: From a total of 1070 patients regularly monitored in our HF Clinic between January 2011 and September 2017, the clinical records of 224 patients with HF and reduced EF on optimized GDMT were retrospectively analyzed. RESULTS: Of 224 analyzed patients, 75 improved their EF or were asymptomatic after uptitration of GDMT during follow-up; 50 were not on angiotensin-converting enzyme inhibitor or angiotensin receptor blocker for different reasons; 13 patients had systolic blood pressure ≤100 mm Hg, so they were not eligible for sacubitril/valsartan introduction. The remaining patients were still symptomatic (NYHA ≥2), and therefore, sacubitril/valsartan introduction was indicated in these 86 patients (38.4%) of 224 enrolled. CONCLUSION: In patients with HF and reduced EF, where GDMT is appropriately achieved, indication to sacubitril/valsartan treatment is around 38%.
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Aminobutiratos/uso terapéutico , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Insuficiencia Cardíaca Sistólica/tratamiento farmacológico , Inhibidores de Proteasas/uso terapéutico , Volumen Sistólico/efectos de los fármacos , Tetrazoles/uso terapéutico , Función Ventricular Izquierda/efectos de los fármacos , Anciano , Anciano de 80 o más Años , Aminobutiratos/efectos adversos , Bloqueadores del Receptor Tipo 1 de Angiotensina II/efectos adversos , Compuestos de Bifenilo , Enfermedad Crónica , Toma de Decisiones Clínicas , Combinación de Medicamentos , Determinación de la Elegibilidad , Femenino , Adhesión a Directriz , Insuficiencia Cardíaca Sistólica/diagnóstico por imagen , Insuficiencia Cardíaca Sistólica/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Neprilisina/antagonistas & inhibidores , Guías de Práctica Clínica como Asunto , Inhibidores de Proteasas/efectos adversos , Recuperación de la Función , Estudios Retrospectivos , Tetrazoles/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , ValsartánRESUMEN
Central core disease (CCD) is a congenital myopathy linked to mutations in the ryanodine receptor type 1 (RYR1), the sarcoplasmic reticulum Ca2+ release channel of skeletal muscle. CCD is characterized by formation of amorphous cores within muscle fibers, lacking mitochondrial activity. In skeletal muscle of RYR1Y522S/WT knock-in mice, carrying a human mutation in RYR1 linked to malignant hyperthermia (MH) with cores, oxidative stress is elevated and fibers present severe mitochondrial damage and cores. We treated RYR1Y522S/WT mice with N-acetylcysteine (NAC), an antioxidant provided ad libitum in drinking water for either 2 or 6 months. Our results show that 2 months of NAC treatment starting at 2 months of age, when mitochondrial and fiber damage was still minimal, (i) reduce formation of unstructured and contracture cores, (ii) improve muscle function, and (iii) decrease mitochondrial damage. The beneficial effect of NAC treatment is also evident following 6 months of treatment starting at 4 months of age, when structural damage was at an advanced stage. NAC exerts its protective effect likely by lowering oxidative stress, as supported by the reduction of 3-NT and SOD2 levels. This work suggests that NAC administration is beneficial to prevent mitochondrial damage and formation of cores and improve muscle function in RYR1Y522S/WT mice.
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Antioxidantes/metabolismo , Músculo Esquelético/fisiología , Miopatía del Núcleo Central/genética , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Animales , Humanos , Ratones , Miopatía del Núcleo Central/patologíaRESUMEN
BACKGROUND: Mice lacking calsequestrin-1 (CASQ1-null), a Ca-binding protein that modulates the activity of Ca release in the skeletal muscle, exhibit lethal hypermetabolic episodes that resemble malignant hyperthermia in humans when exposed to halothane or heat stress. METHODS: Because oxidative species may play a critical role in malignant hyperthermia crises, we treated CASQ1-null mice with two antioxidants, N-acetylcysteine (NAC, Sigma-Aldrich, Italy; provided ad libitum in drinking water) and (±)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox, Sigma-Aldrich; administered by intraperitoneal injection), before exposure to halothane (2%, 1 h) or heat (41°C, 1 h). RESULTS: NAC and Trolox significantly protected CASQ1-null mice from lethal episodes, with mortality being 79% (n = 14), 25% (n = 16), and 20% (n = 5) during halothane exposure and 86% (n = 21), 29% (n = 21), and 33% (n = 6) during heat stress in untreated, NAC-treated, and Trolox-treated mice, respectively. During heat challenge, an increase in core temperature in CASQ1-null mice (42.3° ± 0.1°C, n=10) was significantly reduced by both NAC and Trolox (40.6° ± 0.3°C, n = 6 and 40.5° ± 0.2°C, n = 6). NAC treatment of CASQ1-null muscles/mice normalized caffeine sensitivity during in vitro contracture tests, Ca transients in single fibers, and significantly reduced the percentage of fibers undergoing rhabdomyolysis (37.6 ± 2.5%, 38/101 fibers in 3 mice; 11.6 ± 1.1%, 21/186 fibers in 5 mice). The protective effect of antioxidant treatment likely resulted from mitigation of oxidative stress, because NAC reduced mitochondrial superoxide production, superoxide dismutase type-1 expression, and 3-nitrotyrosine expression, and increased both reduced glutathione and reduced glutathione/oxidized glutathione ratio. CONCLUSION: These studies provide a deeper understanding of the mechanisms that underlie hyperthermic crises in CASQ1-deficient muscle and demonstrate that antioxidant pretreatment may prevent them.
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Anestésicos por Inhalación/toxicidad , Antioxidantes/uso terapéutico , Proteínas de Unión al Calcio/deficiencia , Muerte Súbita/prevención & control , Halotano/toxicidad , Calor/efectos adversos , Animales , Calsecuestrina , Masculino , Ratones , Ratones NoqueadosRESUMEN
CONTEXT: Heterozygous mutations in the TSH receptor gene (TSHR) are associated with partial TSH resistance, characterized by isolated nonautoimmune hyperthyrotropinemia (NAHT). The prevalence and management of this condition is controversial. OBJECTIVE: Our objective was to investigate the prevalence and clinical impact of TSHR alterations in a large series of pediatric patients with NAHT and to dissect their mechanism of action. DESIGN AND SETTING: For this prospective multicenter study, clinical data and samples were collected in the clinical units and conveyed to a centralized laboratory for analysis. PATIENTS: Subjects included 153 unrelated patients with NAHT aged <18 yr. Exclusion criteria included thyroid dysgenesis or major associated congenital defects. MAIN OUTCOME MEASURES: Parameters of thyroid function, TSHR gene analysis, and TSHR functional assays were evaluated. RESULTS: The frequency of heterozygous nonpolymorphic TSHR variations was 11.8%. We identified seven previously unknown variations: a frameshift (p.Q33PfsX46), one intronic (g.IVS4+2AâG), and five novel missense (p.P162L, p.Y466C, p.I583T, p.I607T, and p.R609Q) variations. The missense variations variably affected TSHR membrane expression and G(s) and/or G(q/11) signaling. Several variations cosegregated with NAHT in the affected families. Parameters of thyroid function were similar between affected and unaffected family members. CONCLUSIONS: Nonpolymorphic alterations in the TSHR gene are commonly associated with isolated NAHT in young patients, thus configuring partial TSH resistance as the most frequent inheritable cause of isolated NAHT. The identification of TSHR defects may thus be helpful for a tailored management of subclinical hypothyroidism. We provide further evidence that besides the well-known defects in G(s) signaling, TSHR genetic alternations found in NAHT may frequently impair the G(q/11) pathway.
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Receptores de Tirotropina/genética , Enfermedades de la Tiroides/genética , Tirotropina/sangre , Adolescente , Animales , Células COS , Niño , Preescolar , Chlorocebus aethiops , Femenino , Frecuencia de los Genes , Humanos , Lactante , Recién Nacido , Masculino , Linaje , Transducción de Señal/genética , Enfermedades de la Tiroides/sangre , Enfermedades de la Tiroides/metabolismo , Tirotropina/metabolismo , TransfecciónRESUMEN
SCOPE: Cardiovascular disease (CVD) is associated with vascular oxidative imbalance and inflammation. Increased reactive oxygen species (ROS) generation is associated with a functional inactivation of nitric oxide (NO) due to the reaction with O2â», leading to peroxynitrite (ONOOâ») formation and subsequent reduction in the beneficial effect of vascular NO bioavailability. Carotenoids'-rich diets have been associated with decreased risk of CVD, but the underlying mechanism is still unknown. METHODS AND RESULTS: In human umbilical vein endothelial cells (HUVECs), both ß-carotene (BC) or lycopene (Lyc) significantly affected tumor necrosis factor-α (TNF-α)-induced inflammation, being associated with a significant decrease in the generation of ROS (spectrofluorometry) and nitrotyrosine (an index of ONOOâ» formation, cytofluorimetry), an increased NO/cGMP (cyclic guanosine monophosphate) levels (EIA), and a down-regulation of NF-κB-dependent adhesion molecule expression (Western blot and EMSA) and monocyte-HUVEC interaction (adhesion assay). Our results indicate that BC or Lyc treatment reduce the inflammatory response in TNF-α-treated HUVECs. This is due to the redox balance protection and to the maintenance of NO bioavailability. CONCLUSION: Our observations provide background for a novel mechanism for carotenoids' anti-inflammatory activity in the vasculature and may contribute to a better understanding of the protective effects of carotenoid-rich diets against CVD risk.
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Carotenoides/farmacología , Monocitos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo , beta Caroteno/farmacología , Antiinflamatorios no Esteroideos/farmacología , Disponibilidad Biológica , Carotenoides/farmacocinética , Adhesión Celular/efectos de los fármacos , Moléculas de Adhesión Celular/metabolismo , GMP Cíclico/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Licopeno , Monocitos/citología , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Tirosina/análogos & derivados , Tirosina/metabolismo , beta Caroteno/farmacocinéticaRESUMEN
Catalyst 5, an ion pair consisting of a hydrophilic cation and a lipophilic anion, fulfils the solubility requirements needed to couple efficiency (enantioselectivities and anti-diastereoselectivities up to > or = 99%) and catalyst recyclability in asymmetric aldol reactions under aqueous biphasic conditions.