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1.
Clin Radiol ; 74(3): 220-227, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30554806

RESUMEN

AIM: To identify, in vitro, the best fruit juice to use as oral contrast agent in magnetic resonance cholangiopancreatography (MRCP) and to test, in vivo, the best natural juice and the new parameters in MRCP sequences identified in vitro. MATERIALS AND METHODS: The in vitro evaluations consisted of measuring the T2 values of a pure solution of manganese (Mn) and iron (Fe) at different concentrations, measuring the content of Mn and Fe in five commercial juices and their T2 relaxation times, and identifying the optimal juice dilution for suppressing the gastrointestinal fluid signal. The new parameters of MRCP sequences were tested in vivo. RESULTS: Manganese alone strongly influenced the shortening of the T2 values (p=0.004). The T2 value with an echo time (TE) of ≥1,000 ms enabled sufficient intestinal fluid suppression in the case of high juice dilution. A flip angle of 90° maximised the differences between the high signal from static fluids, such as the bile and the fluid in the gastrointestinal tract, using fast imaging employing steady-state acquisition (FIESTA) sequences (p<0.001). CONCLUSION: The shortening of the T2 relaxation time depended only on the Mn concentration. All the commercial juices had an Mn concentration sufficient to suppress the gastrointestinal fluid signal using long TE sequences. The oral ingestion of commercial juice before MRCP was enough to suppress the signal from the gastrointestinal fluids, regardless of its dilution after ingestion. When using FIESTA sequences, a flip angle of 90° allowed the best suppression of gastrointestinal fluid signals.


Asunto(s)
Pancreatocolangiografía por Resonancia Magnética/métodos , Medios de Contraste/administración & dosificación , Jugos de Frutas y Vegetales , Administración Oral , Medios de Contraste/química , Humanos , Técnicas In Vitro , Hierro/química , Manganeso/química
2.
Transl Psychiatry ; 14(1): 298, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39030169

RESUMEN

Excessive alcohol consumption remains a global public health crisis, with millions suffering from alcohol use disorder (AUD, or simply "alcoholism"), leading to significantly reduced life expectancy. This review examines the interplay between habitual and goal-directed behaviors and the associated neurobiological changes induced by chronic alcohol exposure. Contrary to a strict habit-goal dichotomy, our meta-analysis of the published animal experiments combined with a review of human studies reveals a nuanced transition between these behavioral control systems, emphasizing the need for refined terminology to capture the probabilistic nature of decision biases in individuals with a history of chronic alcohol exposure. Furthermore, we distinguish habitual responding from compulsivity, viewing them as separate entities with diverse roles throughout the stages of the addiction cycle. By addressing species-specific differences and translational challenges in habit research, we provide insights to enhance future investigations and inform strategies for combatting AUD.


Asunto(s)
Alcoholismo , Objetivos , Hábitos , Humanos , Alcoholismo/psicología , Animales , Conducta Adictiva/psicología , Consumo de Bebidas Alcohólicas/psicología
3.
Artículo en Inglés | MEDLINE | ID: mdl-24378467

RESUMEN

A relatively fast analytical method for the identification and quantification of the post-transcriptional changes (PTCs) occurring in circulating human serum albumin (HSA) was developed. HSA is the most abundant protein in plasma and it represents the main determinant of plasma oncotic pressure, thus being the main modulator of fluid distribution between body compartments. Cirrhotic patients have low levels of HSA. Moreover, recent studies have demonstrated that during liver cirrhosis HSA presents PTCs affecting its properties. The HSA isoforms derived from these modifications could represent promising biomarkers for liver disease. Human plasma samples were collected from a cirrhotic patient (CH) and from an aged-matched non- cirrhotic subject (CT), purified by reverse-phase chromatography and analysed by an electrospray ionization quadrupole time-of-flight (ESI-Q-ToF) spectrometer. The deconvoluted ESI mass spectra from healthy subjects were all characterized by peaks attributed to mercaptoalbumin, nitrosylated, cysteinylated, glycated and N- terminal truncated HSA isoforms. The relative abundance of each isoform was derived and transformed into a relative per cent amount and the results were compared to those obtained analysing HSA from a CH plasma. The method was validated in terms of intra-day and inter-day reproducibility, both for quantitative results and PTCs molecular weight determination. The optimized method resulted in being effective in disclosing changes in HSA isoforms relative abundance and then it could be used for the systematic screening of cirrhotic patients to identify promising new biomarkers for liver diseases.


Asunto(s)
Fibrosis/metabolismo , Espectrometría de Masas/métodos , Espectrometría de Masas/normas , Albúmina Sérica/análisis , Albúmina Sérica/metabolismo , Biomarcadores/análisis , Biomarcadores/metabolismo , Química Clínica/métodos , Química Clínica/normas , Humanos , Tamizaje Masivo/métodos , Tamizaje Masivo/normas , Persona de Mediana Edad , Procesamiento Proteico-Postraduccional , Reproducibilidad de los Resultados , Albúmina Sérica/química , Relación Estructura-Actividad
4.
J Bioenerg Biomembr ; 43(6): 673-82, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22015484

RESUMEN

Liver ischemia-reperfusion injury is still an open problem in many clinical circumstances, including surgery and transplantation. This study investigates how mitochondrial structure, mass and oxidative phosphorylation change and may be preserved during a brief period of ischemia followed by a long period of reperfusion, an experimental model that mimics the condition to which a liver is exposed during transplantation. Livers were explanted from rats and exposed for 24 h to three different oxygen availability conditions at 4 °C. Mitochondrial mass, respiration, oxidative phosphorylation (OXPHOS), and levels of OXPHOS complexes were all significantly altered in livers stored under the currently used preservation condition of normoxia. Remarkably, liver perfusion with hyperoxic solutions fully preserved mitochondrial morphology and function, suggesting that perfusion of the graft with hyperoxic solution should be considered in human transplantation.


Asunto(s)
Hiperoxia/metabolismo , Hígado/metabolismo , Mitocondrias Hepáticas/metabolismo , Fosforilación Oxidativa , Consumo de Oxígeno , Animales , Humanos , Hiperoxia/patología , Isquemia/metabolismo , Isquemia/patología , Hígado/patología , Trasplante de Hígado , Mitocondrias Hepáticas/patología , Ratas , Ratas Sprague-Dawley , Reperfusión
5.
Gut ; 58(8): 1135-43, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19282305

RESUMEN

BACKGROUND/AIM: Endotoxaemia can complicate hepatic ischaemia-reperfusion (IR) injury. Endocannabinoids appear to modulate the haemodynamic alterations and cytokine response induced by lipopolysaccharide (LPS). Thus, we aimed to determine the effect of the endocannabinoid CB1-receptor antagonist Rimonabant in a model of hepatic IR injury complicated by endotoxaemia. METHODS: Sprague-Dawley rats pre-treated with Rimonabant 3 or 10 mg/kg or vehicle underwent partial hepatic IR and lipopolysaccharide (LPS) injection at reperfusion. Liver injury was evaluated by serum alanine aminotransferase (ALT) and necrotic-cell count. The inflammatory response was investigated by assessing hepatic neutrophil infiltration, tumour necrosis factor alpha (TNFalpha), interferon gamma (IFNgamma), interleukin 6 (IL6), and suppressor of cytokine signalling (SOCS) 1 and SOCS3 gene expression by real-time polymerase chain reaction (RT-PCR). Systolic blood pressure and hepatic blood flow were measured as haemodynamic parameters. Finally, lipid peroxidation, glutathione status, and immunoreactive CB1 receptor expression in the liver were also determined. RESULTS: Liver injury and neutrophil infiltration occurring in the late-phase of LPS-enhanced IR were significantly reduced by CB1-receptor antagonism. Rimonabant-treated rats showed significantly higher gene expression of IFNgamma, IL6, SOCS1 and SOCS3 in "early" reperfusion, while that of TNFalpha was reduced. These findings were associated with increased STAT3 phosphorylation. Furthermore, CB1-receptor antagonism significantly improved the oxidative injury and haemodynamic alterations occurring during reperfusion in untreated rats. Finally, CB1-receptor immunoreactivity was upregulated early after reperfusion. CONCLUSIONS: This study demonstrates that CB1-receptor antagonism protects the liver against LPS-enhanced IR injury by interfering with the inflammatory response that causes the late, neutrophil-dependent phase of reperfusion injury, although the prevention of the transient endotoxin-related hypotension occurring early during reperfusion may be also involved.


Asunto(s)
Endotoxemia/etiología , Hígado/irrigación sanguínea , Piperidinas/uso terapéutico , Pirazoles/uso terapéutico , Receptor Cannabinoide CB1/antagonistas & inhibidores , Daño por Reperfusión/prevención & control , Alanina Transaminasa/sangre , Animales , Presión Sanguínea/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Lipopolisacáridos , Hígado/metabolismo , Hígado/patología , Circulación Hepática/efectos de los fármacos , Masculino , Necrosis , Infiltración Neutrófila , Ratas , Ratas Sprague-Dawley , Receptor Cannabinoide CB1/metabolismo , Daño por Reperfusión/complicaciones , Daño por Reperfusión/metabolismo , Rimonabant
6.
Dig Liver Dis ; 39(10): 943-51, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17692581

RESUMEN

BACKGROUND/AIM: Controversial experimental observations suggest that granulocyte colony stimulating-factor may promote hepatic regeneration after hepatectomy and chemical injury either by directly stimulating adult liver cells or facilitating the mobilization of bone marrow cells and their homing to the liver. We investigated whether different schedules of granulocyte colony stimulating-factor administration protect against experimental acute liver injury. METHODS: Acute liver injury was induced in Sprague-Dawley fed rats by injecting a single intraperitoneal dose of carbon tetrachloride. Recombinant human granulocyte colony stimulating-factor or vehicle was given daily after intoxication (4 days) or before (7 days) and after carbon tetrachloride administration. Liver injury and regeneration were assessed 2 and 4 days after damage. Bone marrow cells mobilization was evaluated by the white blood cell count and the assessment of circulating clonogenic haematopoietic progenitors (colony forming unit-cells). RESULTS: In this experimental model, although granulocyte colony stimulating-factor induced the significant mobilization of colony forming unit-cells, the study cytokine had no effect on liver injury (serum alanine amino transaminase level and necrotic index) and liver regeneration (mitotic index and bromodeoxyuridine incorporation), regardless of the administration schedule. CONCLUSIONS: This study does not support the conclusion that: (1) granulocyte colony stimulating-factor exerts a protective effect against toxic-induced, non-lethal acute liver injury and (2) promotes hepatocyte regeneration.


Asunto(s)
Factores Estimulantes de Colonias/uso terapéutico , Fallo Hepático Agudo/tratamiento farmacológico , Animales , Tetracloruro de Carbono/toxicidad , Modelos Animales de Enfermedad , Citometría de Imagen , Inmunohistoquímica , Recuento de Leucocitos , Fallo Hepático Agudo/inducido químicamente , Fallo Hepático Agudo/patología , Regeneración Hepática/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes , Resultado del Tratamiento
7.
Transplant Proc ; 49(4): 646-649, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28457364

RESUMEN

During the last century, obesity has become a global epidemic. The effect of obesity on renal transplantation may occur in perioperative complications and impairment of organ function. Obese patients have metabolic derangements that can be exacerbated after transplantation and obesity directly impacts most transplantation outcomes. These recipients are more likely to develop adverse graft events, such as delayed graft function and early graft loss. Furthermore, obesity is synergic to some immunosuppressive agents in triggering diabetes and hypertension. As behavioral weight loss programs show disappointing results in these patients, bariatric surgery has been considered as a means to achieve rapid and long-term weight loss. Up-to-date literature shows laparoscopic bariatric surgery is feasible and safe in transplantation candidates and increases the rate of transplantation eligibility in obese patients with end-stage organ disease. There is no evidence that restrictive procedures modify the absorption of immunosuppressive medications. From 2013 to 2016 we performed six bariatric procedures (sleeve gastrectomy) on obese patients with renal transplantation; mean preoperative body mass index (BMI) was 39.8 kg/m2. No postoperative complication was observed and no change in the immunosuppressive medications regimen was needed. Mean observed estimated weight loss was 27.6%, 44.1%, 74.2%, and 75.9% at 1, 3, 6, and 12 months follow-up, respectively. Our recommendation is to consider patients with BMI >30 kg/m2 as temporarily ineligible for transplantation and as candidates to bariatric surgery if BMI >35 kg/m2. We consider laparoscopic sleeve gastrectomy as a feasible, first-choice procedure in this specific population.


Asunto(s)
Cirugía Bariátrica , Gastrectomía , Trasplante de Riñón , Obesidad/cirugía , Adulto , Índice de Masa Corporal , Femenino , Humanos , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Complicaciones Posoperatorias/epidemiología
8.
Oncogene ; 33(35): 4396-406, 2014 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-24531714

RESUMEN

Chronic inflammation is an established risk factor for the onset of cancer, and the inflammatory cytokine IL-6 has a role in tumorigenesis by enhancing proliferation and hindering apoptosis. As factors stimulating proliferation also downregulate p53 expression by enhancing ribosome biogenesis, we hypothesized that IL-6 may cause similar changes in inflamed tissues, thus activating a mechanism that favors neoplastic transformation. Here, we showed that IL-6 downregulated the expression and activity of p53 in transformed and untransformed human cell lines. This was the consequence of IL-6-dependent stimulation of c-MYC mRNA translation, which was responsible for the upregulation of rRNA transcription. The enhanced rRNA transcription stimulated the MDM2-mediated proteasomal degradation of p53, by reducing the availability of ribosome proteins for MDM2 binding. The p53 downregulation induced the acquisition of cellular phenotypic changes characteristic of epithelial-mesenchymal transition, such as a reduced level of E-cadherin expression, increased cell invasiveness and a decreased response to cytotoxic stresses. We found that these changes also occurred in colon epithelial cells of patients with ulcerative colitis, a very representative example of chronic inflammation at high risk for tumor development. Histochemical and immunohistochemical analysis of colon biopsy samples showed an upregulation of ribosome biogenesis, a reduced expression of p53, together with a focal reduction or absence of E-cadherin expression in chronic colitis in comparison with normal mucosa samples. These changes disappeared after treatment with anti-inflammatory drugs. Taken together, the present results highlight a new mechanism that may link chronic inflammation to cancer, based on p53 downregulation, which is activated by the enhancement of rRNA transcription upon IL-6 exposure.


Asunto(s)
Colitis Ulcerosa/metabolismo , Neoplasias del Colon/metabolismo , Transición Epitelial-Mesenquimal/efectos de los fármacos , Interleucina-6/farmacología , ARN Ribosómico/genética , Proteína p53 Supresora de Tumor/metabolismo , Adulto , Antiinflamatorios/uso terapéutico , Cadherinas/metabolismo , Línea Celular Tumoral , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/patología , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Humanos , Masculino , Persona de Mediana Edad , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , ARN Ribosómico/metabolismo , Proteínas Ribosómicas/metabolismo , Ribosomas/genética , Ribosomas/metabolismo , Transducción de Señal , Proteína p53 Supresora de Tumor/genética
9.
Int J Impot Res ; 25(1): 7-11, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22739456

RESUMEN

Recent data report an important role of testosterone (T) in modulating female sexual responses, but little is known about the expression and distribution of androgen receptor (AR) in the human vagina. Therefore, the aims of our study were to evaluate the expression of AR in the human vagina in premenopausal (PrM) and menopausal (M) women and in T-treated women. Vaginal biopsies were obtained from PrM and postmenopausal women and from women with gender identity disorder (female to male (FtM)) receiving exogenous T. AR gene and protein expression levels in vaginal tissues were determined by real-time PCR and western blot analysis, respectively, whereas the localization of AR in vaginal mucosa and stroma was performed by immunohistochemistry. ARs were detected by immunostaining both in the mucosa and stroma. In vaginal mucosa, AR density score decreases with age but does not change with T administration. In stromal tissue, AR density score does not change with age but significantly increases with T administration (P<0.01). AR protein expression was significantly increased in FtM subjects (P<0.001). The expression of AR messenger RNA (mRNA) evaluated by Real-time PCR showed a significantly higher mRNA expression in FtM versus M patients (P<0.01) and in PrM versus M subjects (P<0.05). In conclusion, we found AR protein and mRNA expression both in the epithelium and stroma of the human vagina in all groups of women. A negative correlation exists between age and AR expression in the vaginal mucosa. T administration increases AR expression in both the mucosa and stroma.


Asunto(s)
Menopausia/metabolismo , Premenopausia/metabolismo , Receptores Androgénicos/metabolismo , Testosterona/farmacología , Vagina/metabolismo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Receptores Androgénicos/genética , Procedimientos de Reasignación de Sexo , Vagina/efectos de los fármacos , Vagina/cirugía
10.
Int J Impot Res ; 25(5): 172-7, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23552580

RESUMEN

To date, the effects of long-term testosterone (T) administration on the human vagina are not completely understood. Thus, the aim of this study was to investigate the effects of long-term T treatment on vaginal tissue histology, estrogen receptor alpha (ERα) and beta (ERß) expression and proliferation in female to male transsexual subjects (FtM). We compared vaginal samples from FtM subjects with those of premenopausal women (PrM) and postmenopausal women (M) not receiving any hormonal treatment for at least 2 years. Vaginal tissue samples from 16 FtM subjects treated with T (intramuscular injections of 100 mg Testoviron Depot/7-10 days for at least 1 year), undergoing sex reassignment surgery, and 16 PrM and 16 M subjects undergoing a vaginal hysterectomy for prolapse, were collected. For each sample, morphology, glycogen content, proliferation (ki-67), ERα and ERß expression were evaluated. Vaginal samples from FtM showed a loss of normal architecture of the epithelium, intermediate and superficial layers were completely lost, and glycogen content was depleted. T administration resulted in a strong proliferation reduction when compared with both M and PrM subjects. Stromal and epithelial ERα as well as ERß were significantly decreased in FtM when compared with PrM subjects. In conclusion, our data suggests that systemic T administration at supraphysiological dosage, determines profound changes in histomorphology and reduces ERs expression and proliferation of vaginal epithelium.


Asunto(s)
Epitelio/efectos de los fármacos , Receptor alfa de Estrógeno/análisis , Receptor beta de Estrógeno/análisis , Procedimientos de Reasignación de Sexo , Testosterona/administración & dosificación , Vagina/efectos de los fármacos , Adulto , Anciano , Combinación de Medicamentos , Epitelio/anatomía & histología , Femenino , Glucógeno/análisis , Humanos , Antígeno Ki-67/análisis , Persona de Mediana Edad , Posmenopausia , Premenopausia , Transexualidad , Vagina/anatomía & histología
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