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Oscillatory activity in the local field potential (LFP) is thought to be a marker of cognitive processes. To understand how it differentiates tasks and brain areas in humans, we recorded LFPs in 15 adults with intracranial depth electrodes, as they performed visual-spatial and shape working memory tasks. Stimulus appearance produced widespread, broad-band activation, including in occipital, parietal, temporal, insular, and prefrontal cortex, and the amygdala and hippocampus. Occipital cortex was characterized by most elevated power in the high-gamma (100-150 Hz) range during the visual stimulus presentation. The most consistent feature of the delay period was a systematic pattern of modulation in the beta frequency (16-40 Hz), which included a decrease in power of variable timing across areas, and rebound during the delay period. These results reveal the widespread nature of oscillatory activity across a broad brain network and region-specific signatures of oscillatory processes associated with visual working memory.
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Oscillatory activity is thought to be a marker of cognitive processes, although its role and distribution across the brain during working memory has been a matter of debate. To understand how oscillatory activity differentiates tasks and brain areas in humans, we recorded local field potentials (LFPs) in 12 adults as they performed visual-spatial and shape-matching memory tasks. Tasks were designed to engage working memory processes at a range of delay intervals between stimulus delivery and response initiation. LFPs were recorded using intracranial depth electrodes implanted to localize seizures for management of intractable epilepsy. Task-related LFP power analyses revealed an extensive network of cortical regions that were activated during the presentation of visual stimuli and during their maintenance in working memory, including occipital, parietal, temporal, insular, and prefrontal cortical areas, and subcortical structures including the amygdala and hippocampus. Across most brain areas, the appearance of a stimulus produced broadband power increase, while gamma power was evident during the delay interval of the working memory task. Notable differences between areas included that occipital cortex was characterized by elevated power in the high gamma (100-150 Hz) range during the 500 ms of visual stimulus presentation, which was less pronounced or absent in other areas. A decrease in power centered in beta frequency (16-40 Hz) was also observed after the stimulus presentation, whose magnitude differed across areas. These results reveal the interplay of oscillatory activity across a broad network, and region-specific signatures of oscillatory processes associated with visual working memory.
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Despite prior efforts to understand and target dynapenia (age-induced loss of muscle strength), this condition remains a major challenge that reduces the quality of life in the aged population. We have focused on the neuromuscular junction (NMJ) where changes in structure and function have rarely been systematically studied as a dynamic and progressive process. Our cross-sectional study found neurotransmission at the male mouse NMJ to be biphasic, displaying an early increase followed by a later decrease, and this phenotype was associated with structural changes to the NMJ. A cross-sectional characterization showed that age-induced alterations fell into four age groups: young adult (3-6 months), adult (7-18 months), early aged (19-24 months), and later aged (25-30 months). We then utilized a small molecule therapeutic candidate, GV-58, applied acutely during the later aged stage to combat age-induced reductions in transmitter release by increasing calcium influx during an action potential, which resulted in a significant increase in transmitter release. This comprehensive study of neuromuscular ageing at the NMJ will enable future research to target critical time points for therapeutic intervention. KEY POINTS: Age-induced frailty and falls are the leading causes of injury-related death and are caused by an age-induced loss of muscle strength due to a combination of neurological and muscular changes. A cross-sectional approach was used to study age-induced changes to the neuromuscular junction in a mouse model, and physiological changes that were biphasic over the ageing time course were found. Changes in physiology at the neuromuscular junction were correlated with alterations in neuromuscular junction morphology. An acutely applied positive allosteric gating modifier of presynaptic voltage-gated calcium channels was tested as a candidate therapeutic strategy that could increase transmitter release at aged neuromuscular junctions. These results provide a detailed time course of age-induced changes at the neuromuscular junction in a mouse model and test a candidate therapeutic strategy for weakness.
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Fragilidad , Calidad de Vida , Masculino , Animales , Ratones , Estudios Transversales , Potenciales de Acción , Envejecimiento , Modelos Animales de Enfermedad , Unión NeuromuscularRESUMEN
Ex vivo lung perfusion (EVLP) allows the ventilation and perfusion of lungs to evaluate their viability for transplantation. The aim of this study is to compare the mechanical, morphologic and functional properties of lungs during EVLP with values obtained in vivo to guide a safe mechanical ventilation strategy. Lungs from 5 healthy pigs were studied in vivo and during 4 hours of EVLP. Lung compliance, airway resistance, gas exchange, and hemodynamic parameters were collected at positive end-expiratory pressure (PEEP) of 5 cm H2O. Computed tomography was performed at PEEP 0, PEEP 5, and total lung capacity (TLC). Lung pressure-volume (PV) curves were performed from PEEP 0 to TLC. Lung compliance decreased during EVLP (53 ± 5 mL/cm H2O vs 29 ± 7 mL/cm H2O, P < .05), and the PV curve showed a lower inflection point. Gas content (528 ± 118 mL vs 892 ± 402 mL at PEEP 0) and airway resistance (25 ± 5 vs 44 ± 9 cmH2O/L∗s-1, P < .05) were higher during EVLP. Alveolar dead space (5% ± 2% vs 17% ± 6%, P < .05) and intrapulmonary shunt (9% ± 2% vs 28% ± 13%, P < .05) increased ex vivo compared to in vivo, while the partial pressure of oxygen to inspired oxygen fraction ratio (PO2/FiO2) did not differ (468 ± 52 mm Hg vs 536 ± 14 mm Hg). In conclusion, during EVLP lungs show signs of air trapping and bronchoconstriction, resulting in low compliance and increased alveolar dead space. Intrapulmonary shunt is high despite oxygenation levels acceptable for transplantation.
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Pulmón , Preservación de Órganos/métodos , Perfusión/instrumentación , Perfusión/métodos , Recolección de Tejidos y Órganos/métodos , Animales , Femenino , Pulmón/fisiopatología , Rendimiento Pulmonar/fisiología , Trasplante de Pulmón/métodos , Modelos Animales , Preservación de Órganos/instrumentación , Mecánica Respiratoria/fisiología , PorcinosRESUMEN
Interleukin 10 (IL-10) is an antiinflammatory cytokine, but also promotes B cell responses and plays a pathogenic role in systemic lupus erythematosus (SLE). CD4+CCR6+IL-7R+T cells from human tonsils produced IL-10 following stimulation by naïve B cells, which promoted B cell immunoglobulin G (IgG) production. These tonsillar CCR6+B helper T cells were phenotypically distinct from follicular helper T (TFH) cells and lacked BCL6 expression. In peripheral blood, a CCR6+T cell population with similar characteristics was identified, which lacked Th17- and TFH-associated gene signatures and differentiation-associated surface markers. CD4+CCR6+T cells expressing IL-10, but not IL-17, were also detectable in the spleens of cytokine reporter mice. They provided help for IgG production in vivo, and expanded systemically in pristane-induced lupus-like disease. In SLE patients, CD4+CCR6+IL-7R+T cells were associated with the presence of pathogenic anti-dsDNA (double-stranded DNA) antibodies, and provided spontaneous help for autoantibody production ex vivo. Strikingly, IL-10-producing CCR6+T cells were highly abundant in lymph nodes of SLE patients, and colocalized with B cells at the margins of follicles. In conclusion, we identified a previously uncharacterized population of extrafollicular B helper T cells, which produced IL-10 and could play a prominent pathogenic role in SLE.
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Linfocitos B/inmunología , Interleucina-10/inmunología , Lupus Eritematoso Sistémico/inmunología , Receptores CCR6/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Adulto , Animales , Formación de Anticuerpos , Niño , Citocinas/inmunología , Humanos , Interleucina-10/biosíntesis , Interleucina-17/metabolismo , Lupus Eritematoso Sistémico/metabolismo , Ratones , Ratones Endogámicos C57BL , Tonsila Palatina/citología , Tonsila Palatina/inmunología , Receptores CCR6/biosíntesis , Células Th17/inmunologíaRESUMEN
BACKGROUND: Machine perfusion is increasingly utilized in liver transplantation to face the detrimental consequences of the use of extended-criteria donors. Hypothermic oxygenated machine perfusion (HOPE) appears to be more protective relative to static cold storage. Conversely, normothermic machine perfusion (NMP) allows a better graft evaluation. We describe a pilot prospective study on machine perfusion in selected grafts. METHODS: HOPE was executed for all the grafts procured from donors after cardiac death (DCDs) and for livers from donors after brain death (DBDs) requiring prolonged preservation time. NMP was used when a more precise evaluation was needed. Both HOPE and NMP were performed through the portal vein and hepatic artery. RESULTS: From July 2016 to November 2017, we performed 7 HOPE procedures: 5 for DCD and 2 for DBD grafts. Two livers presented with macrovesicular steatosis >30% (1 DCD and 1 DBD). HOPE lasted 240 minutes (180-320 min) with a total ischemia time of 575 minutes (410-810 min). Six grafts were successfully transplanted. One DCD graft required additional evaluation using NMP. The graft was then discarded due to extensive hepatocellular necrosis. In the post-transplant course, acute and chronic renal failure were the main complications affecting 3 and 2 recipients, respectively. In our series, steatosis was the main risk factor for kidney injury. Patient and graft survival rate was 100% and no ischemic cholangiopathies were observed after 270 days (106-582 days). CONCLUSIONS: Our study confirms HOPE safety and efficacy for DCD and DBD grafts. These data are particularly significant for DCD management in the Italian setting where the mandatory 20-minute hands-off interval before death declaration further prolongs warm ischemia time.
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Supervivencia de Injerto , Trasplante de Hígado/métodos , Preservación de Órganos/métodos , Perfusión/métodos , Femenino , Humanos , Trasplante de Hígado/mortalidad , Masculino , Persona de Mediana Edad , Oxígeno , Proyectos Piloto , Estudios ProspectivosRESUMEN
The metabotropic glutamate receptor 2 (mGlu2) plays an important role in the presynaptic control of glutamate release and several mGlu2 positive allosteric modulators (PAMs) have been under assessment for their potential as antipsychotics. The binding mode of mGlu2 PAMs is better characterized in functional terms while few data are available on the relationship between allosteric and orthosteric binding sites. Pharmacological studies characterizing binding and effects of two different chemical series of mGlu2 PAMs are therefore carried out here using the radiolabeled mGlu2 agonist 3[H]-LY354740 and mGlu2 PAM 3[H]-2,2,2-TEMPS. A multidimensional approach to the PAM mechanism of action shows that mGlu2 PAMs increase the affinity of 3[H]-LY354740 for the orthosteric site of mGlu2 as well as the number of 3[H]-LY354740 binding sites. 3[H]-2,2,2-TEMPS binding is also enhanced by the presence of LY354740. New residues in the allosteric rat mGlu2 binding pocket are identified to be crucial for the PAMs ligand binding, among these Tyr3.40 and Asn5.46. Also of remark, in the described experimental conditions S731A (Ser5.42) residue is important only for the mGlu2 PAM LY487379 and not for the compound PAM-1: an example of the structural differences among these mGlu2 PAMs. This study provides a summary of the information generated in the past decade on mGlu2 PAMs adding a detailed molecular investigation of PAM binding mode. Differences among mGlu2 PAM compounds are discussed as well as the mGlu2 regions interacting with mGlu2 PAM and NAM agents and residues driving mGlu2 PAM selectivity. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'.
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Agonistas de Aminoácidos Excitadores/metabolismo , Agonistas de Aminoácidos Excitadores/farmacología , Receptores de Glutamato Metabotrópico/agonistas , Receptores de Glutamato Metabotrópico/fisiología , Regulación Alostérica/efectos de los fármacos , Regulación Alostérica/fisiología , Animales , Sitios de Unión/fisiología , Compuestos Bicíclicos con Puentes/química , Compuestos Bicíclicos con Puentes/metabolismo , Compuestos Bicíclicos con Puentes/farmacología , Agonistas de Aminoácidos Excitadores/química , Ácido Glutámico/metabolismo , Ácido Glutámico/farmacología , Humanos , Estructura Secundaria de ProteínaRESUMEN
INTRODUCTION: the prevalence of malnutrition in children and its impact on clinical outcomes is underrecognized by clinicians in Italy as well as worldwide. A novel definition of pediatric malnutrition has been recently proposed by a working group of the Academy of Nutrition and Dietetics and American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.), based on the correlation between illness and the use of zscores of anthropometric measurements. AIM: to investigate the prevalence of malnutrition and related nutritional support among hospitalized children in Italy, in a nationwide survey performed in a single day (16/4/2015). METHODS: an open access website (http://nday.biomedia.net) was used to collected data from 73 hospitals and 101 wards in 14 Italian regions (1994 patients). Anonymous information was collected on hospitals' characteristics, patient's anthropometry, admission diagnosis, presence of chronic diseases and use of nutritional support: oral nutritional supplements (ONS), enteral nutrition (EN) or parenteral nutrition (PN). Z-scores of anthropometric measurements, calculated with Epi Info 7.1.5, defined nutritional status: wasting was identified by BMI or Weight-for-Length z-score (<-1 mild, <-2 moderate, <-3 severe), stunting by Height-for-Age Z-score <-2. WHO 2006 and CDC 2000 growth charts were used respectively for children younger and older than 2 years old. RESULTS: 1790 complete records were obtained for hospitalized patients aged 0-20 years, with median age 6.16 (0.1-20 years and 53.3% males). 52.9% were aged 0-6 years and 58.8% of children suffered from chronic diseases. Wasting was detected in 28.7% of the total sample with higher occurrence observed in age ranges 0-6 and 14-20 years, while 17.3% of patients showed stunting; surprisingly almost 27% of them were aged 0-2. A ranking of the admission diagnosis with the highest rate of malnutrition was complied. The prevalence of wasting was significantly (p < 0.005) higher amongst children with chronic diseases (34.1% vs. 27.1%); stunting prevalence tripled in patients with chronic disease (24.5% vs. 8.3%). Only 23.5% of malnourished children (17%, 25.6% and 36.7%, respectively mild, moderate and severe malnutrition) received nutritional support: 11.7% received oral nutrition supplements (ONS, modular or complete), 11.5% enteral nutrition (EN, 6.4% via nasogastric tube, 5.1% via gastrostomy) and 6.8 % received parenteral nutrition (PN); in some patients a combination of two. Nutritional support is more commonly used among stunting patients, 39.5% of children under treatment. CONCLUSION: Malnutrition of any grade was observed in nearly 1/3 and stunting in 17% of the reported hospitalized children, and it is likely to be underrecognized as the nutritional support reached only a small part of the malnourished children.
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Trastornos del Crecimiento/epidemiología , Desnutrición/epidemiología , Encuestas Nutricionales , Adolescente , Niño , Desarrollo Infantil , Niño Hospitalizado , Preescolar , Enfermedad Crónica , Femenino , Gráficos de Crecimiento , Trastornos del Crecimiento/terapia , Humanos , Lactante , Italia/epidemiología , Masculino , Desnutrición/diagnóstico , Desnutrición/terapia , Estado Nutricional , Apoyo Nutricional , Prevalencia , Adulto JovenRESUMEN
The metabotropic glutamate receptor 2 (mGlu2) plays an important role in the presynaptic control of glutamate release and several mGlu2 positive allosteric modulators (PAMs) have been under assessment for their potential as antipsychotics. The binding mode of mGlu2 PAMs is better characterized in functional terms while few data are available on the relationship between allosteric and orthosteric binding sites. Pharmacological studies characterizing binding and effects of two different chemical series of mGlu2 PAMs are therefore carried out here using the radiolabeled mGlu2 agonist 3[H]-LY354740 and mGlu2 PAM 3[H]-2,2,2-TEMPS. A multidimensional approach to the PAM mechanism of action shows that mGlu2 PAMs increase the affinity of 3[H]-LY354740 for the orthosteric site of mGlu2 as well as the number of 3[H]-LY354740 binding sites. 3[H]-2,2,2-TEMPS binding is also enhanced by the presence of LY354740. New residues in the allosteric rat mGlu2 binding pocket are identified to be crucial for the PAMs ligand binding, among these Tyr3.40 and Asn5.46. Also of remark, in the described experimental conditions S731A (Ser5.42) residue is important only for the mGlu2 PAM LY487379 and not for the compound PAM-1: an example of the structural differences among these mGlu2 PAMs. This study provides a summary of the information generated in the past decade on mGlu2 PAMs adding a detailed molecular investigation of PAM binding mode. Differences among mGlu2 PAM compounds are discussed as well as the mGlu2 regions interacting with mGlu2 PAM and NAM agents and residues driving mGlu2 PAM selectivity.
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Compuestos Bicíclicos con Puentes/farmacología , Agonistas de Aminoácidos Excitadores/farmacología , Piridinas/farmacología , Receptores de Glutamato Metabotrópico/agonistas , Receptores de Glutamato Metabotrópico/metabolismo , Sulfonamidas/farmacología , Regulación Alostérica , Animales , Sitios de Unión , Células CHO , Calcio , Cricetulus , Células HEK293 , Humanos , Modelos Moleculares , Ratas , Receptores de Glutamato Metabotrópico/químicaRESUMEN
INTRODUCTION: Uncontrolled donors after circulatory determination of death (uDCDD) represent a yet unexplored pool of organs potentially available for transplantation. The aims of this study were to validate a protocol of cardiac death in the pig and to investigate lung function during the process. MATERIALS AND METHODS: Cardiac death was induced in preanesthetized animals with an injection of 600 mg propofol; once systolic blood pressure was <50 mm Hg (Agonal Phase), a 20 mEq bolus of KCl was given and, after asystolia was documented, cardiopulmonary resuscitation (CPR) started, followed by 5 minutes no touch (end-CPR). Invasive blood pressure (BP) and heart rate (HR) were recorded; blood samples taken at baseline, 15 minutes after CPR, and after the no touch period (end-CPR). Computed tomography (CT) scans were taken at baseline and at end-CPR. RESULTS: Agonal phase was reached in 6 ± 1 minutes and lasted 3 ± 1 minutes; average HR was 49 ± 16 beats/min, and BP was 41 ± 12 mm Hg. CPR lasted 35 ± 3 minutes; average HR and BP were 113 ± 32 beats/min and 86 ± 63 mm Hg, respectively. PaO2/FiO2 decreased from 442 ± 31 mm Hg at baseline to 63 ± 36 at end-CPR (P < .001). pH decreased from 7.378 ± 0.045 to 6.931 ± 0.042 (P < .001), with a corresponding increase of lactate from 0.9 ± 0.2 to mmol/L to 12.8 ± 2.1 (P < .001). As assessed using CT scan, total lung volume decreased (baseline vs end-CPR 1107 ± 106 mL vs 617 ± 95; P < .001), whereas noninflated tissue (ie, atelectasis) significantly increased (46 ± 10 g vs 131 ± 89; P = .008). CONCLUSIONS: Lung function greatly deteriorated after cardiac death. The model we set may constitute a reproducible platform for future investigations on lung uDCDD.
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Reanimación Cardiopulmonar , Paro Cardíaco/fisiopatología , Pulmón/fisiopatología , Animales , Presión Sanguínea , Modelos Animales de Enfermedad , Paro Cardíaco/terapia , Frecuencia Cardíaca , Concentración de Iones de Hidrógeno , Pulmón/diagnóstico por imagen , Mediciones del Volumen Pulmonar , Sus scrofa , Porcinos , Obtención de Tejidos y Órganos , Tomografía Computarizada por Rayos XRESUMEN
Neurotoxicity due to the accumulation of mutant proteins is thought to drive pathogenesis in neurodegenerative diseases. Mutations in superoxide dismutase 1 (SOD1) are linked to familial amyotrophic lateral sclerosis (fALS); these mutations result in progressive motor neuron death through one or more acquired toxicities. Interestingly, SOD1 is not only responsible for fALS but may also play a significant role in sporadic ALS; therefore, SOD1 represents a promising therapeutic target. Here, we report slowed disease progression, improved neuromuscular function, and increased survival in an in vivo ALS model following therapeutic delivery of morpholino oligonucleotides (MOs) designed to reduce the synthesis of human SOD1. Neuropathological analysis demonstrated increased motor neuron and axon numbers and a remarkable reduction in astrogliosis and microgliosis. To test this strategy in a human model, we treated human fALS induced pluripotent stem cell (iPSC)-derived motor neurons with MOs; these cells exhibited increased survival and reduced expression of apoptotic markers. Our data demonstrated the efficacy of MO-mediated therapy in mouse and human ALS models, setting the stage for human clinical trials.
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Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/fisiopatología , Superóxido Dismutasa-1/genética , Animales , Apoptosis , Axones/metabolismo , Muerte Celular , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Silenciador del Gen , Células HeLa , Humanos , Células Madre Pluripotentes Inducidas/citología , Inflamación , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuronas Motoras/metabolismo , Oligonucleótidos/genética , Pliegue de Proteína , Médula Espinal/metabolismoRESUMEN
We developed a protocol to procure lungs from uncontrolled donors after circulatory determination of death (NCT02061462). Subjects with cardiovascular collapse, treated on scene by a resuscitation team and transferred to the emergency room, are considered potential donors once declared dead. Exclusion criteria include unwitnessed collapse, no-flow period of >15 min and low flow >60 min. After death, lung preservation with recruitment maneuvers, continuous positive airway pressure, and protective mechanical ventilation is applied to the donor. After procurement, ex vivo lung perfusion (EVLP) is performed. From November 2014, 10 subjects were considered potential donors; one of these underwent the full process of procurement, EVLP, and transplantation. The donor was a 46-year-old male who died because of thoracic aortic dissection. Lungs were procured 4 h and 48 min after death, and deemed suitable for transplantation after EVLP. Lungs were then offered to a rapidly deteriorating recipient with cystic fibrosis (lung allocation score [LAS] 46) who consented to the transplant in this experimental setting. Six months after transplantation, the recipient is in good condition (forced expiratory volume in 1 s 85%) with no signs of rejection. This protocol allowed procurement of lungs from an uncontrolled donor after circulatory determination of death following an extended period of warm ischemia.
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Fibrosis Quística/cirugía , Circulación Extracorporea , Trasplante de Pulmón , Perfusión/métodos , Alveolos Pulmonares , Obtención de Tejidos y Órganos/métodos , Adulto , Anciano , Causas de Muerte , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Respiración Artificial , Donantes de TejidosRESUMEN
Airborne exposure to particulate matter with diameter < 10 mcM (PM10) has been linked to an increased risk of thromboembolic events, but the mechanisms are not completely understood. The aim of this study was to evaluate the effect of PM10 phagocytosis on the release of procoagulant molecules in human differentiating macrophages, and that of PM10 inhalation in an experimental model in rats. Human monocytes were separated from the peripheral blood by the lymphoprep method, differentiated in vitro and treated with standard PM10 or vehicle. Sprague-Dawley rats were instilled intratracheally with PM10 or vehicle alone. The outcome was expression of proinflammatory genes and of tissue factor (TF). In human differentiating macrophages, PM10 exposure upregulated inflammatory genes, but most consistently induced TF mRNA and protein levels, but not TF protein inhibitor, resulting in increased TF membrane expression and a procoagulant phenotype. Differentiation towards the anti-inflammatory M2 phenotype inhibited PM10 -mediated TF expression. TF induction required phagocytosis of PM10 , whereas phagocytosis of inert particles was less effective. PM10 phagocytosis was associated with a gene expression profile consistent with intracellular retention of iron, inducing oxidative stress. Both PM10 and iron activated the stress kinases ERK1/2 pathway, involved in the induction of TF expression. In rats, alveolar exposure to PM10 was associated with pulmonary recruitment of inflammatory cells and resulted in local, but not systemic, induction of TF expression, which was sufficient to increase circulating TF levels. In conclusion, TF induction by differentiating lung macrophages, activated following phagocytosis, contributes to the increased risk of thromboembolic complications associated with PM10 exposure.
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Macrófagos/efectos de los fármacos , Material Particulado/toxicidad , Fagocitosis/efectos de los fármacos , Tromboplastina/biosíntesis , Adulto , Animales , Diferenciación Celular/efectos de los fármacos , Citocalasina D/farmacología , Humanos , Hierro/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/fisiología , Masculino , Ratas , Ratas Sprague-Dawley , Tromboplastina/genéticaRESUMEN
Although survival after liver transplantation (LT) has progressively improved over the last years, an increased prevalence of clinically relevant infections in LT patients is well documented. In particular, the spread of infections sustained by extensively drug-resistant bacteria (XDR) produced an increase in the incidence of wound infections. Implementation of treatments for these life-threatening events is mandatory. This study describes 2 LT patients in whom XDR wound infection was effectively treated using negative pressure wound treatment (NPWT) combined with targeted local and systemic antibiotic therapy. Over the last 3 years, 2 of 8 patients with XDR infection admitted to our unit developed wound infection caused by XDR Klebsiella pneumoniae (KP-XDR). Positive results of the abdominal fluid culture and of the wound swab for KP-XDR were followed by sepsis. In both cases wound debridement was required and deep fascial layer dehiscence was detected. Combination antibiotic therapy was administered for sepsis treatment and, after failure of conventional NPWT, a NPWT with local instillation (NPWTi; V.A.C.-Ulta/VeraFlo-Instillation Therapy-KCI USA, Inc., San Antonio, TX, USA) of colistin-rifampicin was applied. After NPWTi application a reduction in bacterial load and exudate was observed with reduction in inflammatory markers. A complete healing of wound was achieved and both patients are currently alive. Instillation and NPWT are widely discussed in the literature. Results of the present study indicate beneficial effects of NPWT combined with targeted local and systemic antibiotic therapy; in both cases a life-threatening complication was cured. We consider local instillation of selected antibiotics applied to NPWTi a valuable tool for deep wound infection sustained by XDR bacteria.
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Trasplante de Hígado/efectos adversos , Terapia de Presión Negativa para Heridas , Infección de la Herida Quirúrgica/terapia , Antibacterianos/uso terapéutico , Terapia Combinada , Humanos , Klebsiella pneumoniae , Masculino , Persona de Mediana Edad , Infección de la Herida Quirúrgica/microbiología , Cicatrización de HeridasRESUMEN
BACKGROUND: Aim of this study was to compare early graft function after transplantation of recipients transplanted with livers procured from donors after brain death who experienced transient or sustained cardio-circulatory collapse. METHODS: We retrospectively analysed patients who underwent liver transplantation (LTx) at our Institution from January 2010 to May 2012. Recipients were divided into 3 groups: those who received livers from brain death donors who experienced reversible cardio-circulatory arrest before organ procurement (RCA); those who experienced sustained cardio-circulatory collapse, treated with extra-corporeal membrane oxygenation support as rescue therapy of refractory cardiogenic shock (ECMO). Standard donors were considered as reference group (REF). Postoperative graft function, Primary Non-Function (PNF), and complications during the first 30 days were analysed. RESULTS: 102 LTx were analysed (76 REF, 22 RCA and 4 ECMO). The main cause of donor's death was post-anoxic coma in RCA and ECMO, cerebrovascular accident in REF. SGOT in REF, RCA, and ECMO donors were 27 [17-43], 54 [34-92], 716 [190-962] respectively, SGPT 17 [12-34], 46 [27-73], 84 [51-175] UI/L respectively, both P<0.01. All recipients had similar SGOT (P=0.48), SGPT (P=0.75) and Model for End-Stage Liver Disease scores (P=0.98) before LTx; similar graft cold and warm ischemia time and serum lactate levels at the end of surgery. After LTx, Intensive Care Unit stay and the incidence of PNF were similar. CONCLUSION: The use of livers procured from donors after brain death that experienced transient or sustained cardio-circulatory collapse was associated with early graft function comparable to that of standard donors.
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Muerte Encefálica , Trasplante de Hígado/métodos , Choque , Adulto , Anciano , Femenino , Humanos , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Donantes de Tejidos , Resultado del TratamientoRESUMEN
Met, the tyrosine kinase receptor for hepatocyte growth factor (HGF), mainly activates prosurvival pathways, including protection from apoptosis. In this work, we investigated the cardioprotective mechanisms of Met activation by agonist monoclonal antibodies (mAbs). Cobalt chloride (CoCl2), a chemical mimetic of hypoxia, was used to induce cardiac damage in H9c2 cardiomyoblasts, which resulted in reduction of cell viability by (i) caspase-dependent apoptosis and (ii) - surprisingly - autophagy. Blocking either apoptosis with the caspase inhibitor benzyloxycarbonyl-VAD-fluoromethylketone or autophagosome formation with 3-methyladenine prevented loss of cell viability, which suggests that both processes contribute to cardiomyoblast injury. Concomitant treatment with Met-activating antibodies or HGF prevented apoptosis and autophagy. Pro-autophagic Redd1, Bnip3 and phospho-AMPK proteins, which are known to promote autophagy through inactivation of the mTOR pathway, were induced by CoCl2. Mechanistically, Met agonist antibodies or HGF prevented the inhibition of mTOR and reduced the flux of autophagosome formation. Accordingly, their anti-autophagic function was completely blunted by Temsirolimus, a specific mTOR inhibitor. Targeted Met activation was successful also in the setting of low oxygen conditions, in which Met agonist antibodies or HGF demonstrated anti-apoptotic and anti-autophagic effects. Activation of the Met pathway is thus a promising novel therapeutic tool for ischaemic injury.
Asunto(s)
Anticuerpos Monoclonales/farmacología , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Cardiotónicos/farmacología , Citoprotección/efectos de los fármacos , Miocitos Cardíacos/patología , Proteínas Proto-Oncogénicas c-met/agonistas , Animales , Línea Celular , Cobalto , Factor de Crecimiento de Hepatocito/farmacología , Miocitos Cardíacos/efectos de los fármacos , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-met/metabolismo , Ratas , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
MicroRNAs (miRNAs) are natural, single-stranded, small RNA molecules which subtly control gene expression. Several studies indicate that specific miRNAs can regulate heart function both in development and disease. Despite prevention programs and new therapeutic agents, cardiovascular disease remains the main cause of death in developed countries. The elevated number of heart failure episodes is mostly due to myocardial infarction (MI). An increasing number of studies have been carried out reporting changes in miRNAs gene expression and exploring their role in MI and heart failure. In this review, we furnish a critical analysis of where the frontier of knowledge has arrived in the fields of basic and translational research on miRNAs in cardiac ischemia. We first summarize the basal information on miRNA biology and regulation, especially concentrating on the feedback loops which control cardiac-enriched miRNAs. A focus on the role of miRNAs in the pathogenesis of myocardial ischemia and in the attenuation of injury is presented. Particular attention is given to cardiomyocyte death (apoptosis and necrosis), fibrosis, neovascularization, and heart failure. Then, we address the potential of miR-diagnosis (miRNAs as disease biomarkers) and miR-drugs (miRNAs as therapeutic targets) for cardiac ischemia and heart failure. Finally, we evaluate the use of miRNAs in the emerging field of regenerative medicine.
Asunto(s)
Retroalimentación Fisiológica/fisiología , Regulación de la Expresión Génica/genética , Terapia Genética/métodos , MicroARNs/uso terapéutico , Isquemia Miocárdica/genética , Isquemia Miocárdica/terapia , Miocitos Cardíacos/fisiología , Apoptosis/fisiología , Humanos , MicroARNs/genética , Isquemia Miocárdica/fisiopatología , Necrosis/fisiopatología , Neovascularización Fisiológica/fisiología , Medicina Regenerativa/tendenciasRESUMEN
Liver transplantation (LT) in patients with hereditary hemorrhagic telangiectasia (HHT), or Rendu-Osler-Weber, disease is a problematic procedure. In patients with hepatic involvement due to clinically significant arterovenous malformations, there is high risk of intraoperative bleeding and intra- or perioperative complications. Some surgical corrections have been proposed for venous problems, concerning the vena caval anastomosis. A common finding in HHT is arterial enlargement of the celiac trunk and of the common hepatic artery. We report 2 cases of LT in HHT where the arterial anastomosis was successfully performed using the splenic artery of the recipient, which shows less tendency for enlargement than the celiac trunk.
Asunto(s)
Anastomosis Quirúrgica , Arterias/cirugía , Trasplante de Hígado , Telangiectasia Hemorrágica Hereditaria/cirugía , Adulto , Femenino , Humanos , Persona de Mediana Edad , Tomografía Computarizada por Rayos XRESUMEN
Hyperbilirubinemia often accompanies liver failure; therefore, artificial liver support devices are currently used as a bridge to more definitive treatments to eliminate water-soluble and albumin-bound toxins. We report 2 patients, of which, after liver transplantation, the first experienced early allograft dysfunction and the other hyperbilirubinemia linked to chronic rejection. After 3 cycles of coupled plasma filtration adsorption (CPFA), the bilirubin promptly decreased in both cases. CPFA is an extracorporeal therapy that uses plasma filtration associated with an adsorbent cartridge and hemofiltration to remove cytokines and inflammatory mediators associated with septic shock, severe sepsis, and multiple organ dysfunction syndrome. Each cycle of treatment lowered the bilirubin of our patients by â¼40%. CPFA deserves attention as a potential inexpensive short-lasting device to treat hyperbilirubinemia after liver surgery or transplantation. Moreover, the effects of CPFA should be further studied to address inflammatory mediators in chronic rejection after liver transplantation or other immunologic disorders.
Asunto(s)
Hiperbilirrubinemia/etiología , Trasplante de Hígado/efectos adversos , Adsorción , Femenino , Humanos , Masculino , Persona de Mediana Edad , Plasmaféresis/métodosRESUMEN
The diagnosis and clinical management of cystic echinococcosis (CE) rely on imaging and serology, the latter still having a complementary role as its accuracy in assessing cyst viability is unsatisfactory. We used an experimental IgG ELISA test based on the recombinant antigen rEgAgB8/1 cloned from Echinococcus granulosus to differentiate active from inactive/cured CE infection, comparing its performance to that of a commercially available ELISA test used routinely in our hospital laboratory. Both tests were performed on sera from 88 patients with hepatic echinococcal cysts, grouped according to cyst stage based on ultrasonographical morphology, and on 17 patients surgically treated for echinococcosis and 18 patients with nonparasitic hepatic cysts included as controls. Tests' performances did not differ significantly, but the overall concordance between tests drastically dropped when groups were analysed separately. Further longitudinal studies should evaluate whether these discrepancies reflect the different ability of either test to predict the evolution of cysts over time. Although the recombinant-AgB8/1-based ELISA test seems to have no clinical advantage over the commercially available ELISA test in the assessment of hepatic CE cyst viability, the easiness of production and reproducibility of high-quality recombinant antigens makes rEgAgB8/1 a valid candidate for use in CE ELISA diagnostic tests.