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In cancer patients, hyponatremia is detected in about 40% of cases at hospital admission and has been associated to a worse outcome. We have previously observed that cancer cells from different tissues show a significantly increased proliferation rate and invasion potential, when cultured in low extracellular [Na+]. We have recently developed an animal model of hyponatremia using Foxn1nu/nu mice. The aim of the present study was to compare tumor growth and invasivity of the neuroblastoma cell line SK-N-AS in hyponatremic vs. normonatremic mice. Animals were subcutaneously implanted with luciferase-expressing SK-N-AS cells. When masses reached about 100 mm3, hyponatremia was induced in a subgroup of animals via desmopressin infusion. Tumor masses were significantly greater in hyponatremic mice, starting from day 14 and until the day of sacrifice (day 28). Immunohistochemical analysis showed a more intense vascularization and higher levels of expression of the proliferating cell nuclear antigen, chromogranin A and heme oxigenase-1 gene in hyponatremic mice. Finally, metalloproteases were also more abundantly expressed in hyponatremic animals compared to control ones. To our knowledge, this is the first demonstration in an experimental animal model that hyponatremia is associated to increased cancer growth by activating molecular mechanisms that promote proliferation, angiogenesis and invasivity.
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Hiponatremia , Neuroblastoma , Humanos , Ratones , Animales , Hiponatremia/etiología , Xenoinjertos , Sodio/metabolismo , HospitalizaciónRESUMEN
INTRODUCTION: Haemophilia (H) is frequently associated with a multifactorial reduction in bone mineral density (BDM), but little is known about possible differences between HA and HB according to their severity. AIM: To evaluate the association between low bone mineral density (BMD), 25-hydroxyvitamin D [25(OH)D] concentrations and bone turnover markers in patients with HA and HB younger or older than 50 years. METHODS: In 78 patients <50 years and 33 patients >50 years with severe (S) or moderate (M) HA and HB, BMD was measured by dual-energy X-ray absorptiometry at femoral neck (FN) and lumbar spine and then correlated to annual bleeding rate (ABR), World Federation of Haemophilia orthopaedic joint scale (WFH score), 25(OH)D concentrations, parathyroid hormone (PTH), amino-terminal telopeptide of type 1 collagen (NTx), urinary pyridinolines, osteocalcin and bone-specific alkaline phosphatase. RESULTS: Overall, a high prevalence of hypovitaminosis D was diagnosed. In patients <50 years, low FN-BMD was significantly more frequent in HA than in HB, while PTH, pyridinolines, ABR and WFH score were associated with H type and severity. In patients >50 years, similarly low FN-BMD was observed in HA and HB, while ABR and WFH score were associated with H type and severity, being milder in HB. CONCLUSIONS: Low bone mass is a frequent comorbidity in haemophilic patients of all ages, apart from those with MHB. Clinical and laboratory assessments confirm a higher bone impairment and faster bone resorption in HA compared with HB. Looking at H type and severity, MHB seems to have a normal bone metabolism and a less severe disease.
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Densidad Ósea/fisiología , Hemofilia A/complicaciones , Hemofilia B/complicaciones , Deficiencia de Vitamina D/etiología , Femenino , Hemofilia A/sangre , Hemofilia B/sangre , Humanos , Masculino , Persona de Mediana EdadRESUMEN
This document presents the guidelines for onconeural antibody testing that have been developed following a consensus process built on questionnaire-based surveys, internet contacts, and discussions at workshops of the sponsoring Italian Association of Neuroimmunology (AINI) congresses. Essential clinical information on paraneoplastic neurological syndromes, indications and limits of onconeural antibody testing, instructions for result interpretation, and an agreed laboratory protocol (Appendix) are reported for the communicative community of neurologists and clinical pathologists.
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Síndromes Paraneoplásicos del Sistema Nervioso/diagnóstico , Autoanticuerpos/inmunología , Autoanticuerpos/metabolismo , Humanos , Síndromes Paraneoplásicos del Sistema Nervioso/inmunología , Síndromes Paraneoplásicos del Sistema Nervioso/metabolismoRESUMEN
This document presents the guidelines for anti-myelin-associated glycoprotein (MAG) antibody testing that have been developed following a consensus process built on questionnaire-based surveys, internet contacts, and discussions at workshops of sponsoring Italian Association of Neuroimmunology (AINI) congresses. The main clinical information on anti-MAG antibody polyneuropathy, indications and limits of anti-MAG antibody testing, instructions for result interpretation, and an agreed laboratory protocol (Appendix) are reported for the communicative community of neurologists and clinical pathologists.
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Autoanticuerpos , Glicoproteína Asociada a Mielina/inmunología , Polineuropatías/diagnóstico , Humanos , Polineuropatías/inmunologíaRESUMEN
Multiple myeloma (MM) is characterized, in about 80% of cases, by the production of monoclonal intact immunoglobulin and more than 95% of them have elevated concentrations of involved (i.e. of the same class of intact immunoglobulin) free light chain (FLC). The introduction of novel therapeutic strategies has changed the natural history of the disease, leading to new manifestations of relapse. Light chain escape (LCE) is a pattern of relapse in which the FLC increase is not accompanied by a concomitant raise of the original monoclonal component (MC). Here we present a case of a 55-year-old man with an IgG kappa MM stage III diagnosed in September 2007. At presentation an IgG kappa MC and urine Bence Jones protein (BJP) kappa were present. Bone marrow biopsy (BMB) showed the presence of 80% monotypic kappa plasma cells (PCs). The patient received bortezomib, thalidomide, dexamethasone before undergoing a double autologous stem cell transplantation (ASCT) in October 2008 and April 2009. In May 2011 he relapsed showing the same pattern of presentation and treatment with lenalidomide and dexamethasone was started. ln May 2013 serum and urine immunofixation and FLC became negative. In September 2014, an increase of kappa FLC was observed, while serum and urine immunofixations remained negative until January 2015, when urine immunofixation became positive. Eventually, in February 2015, serum immunofixation revealed the presence of a free kappa MC. After a new BMB showing 80% of monotypic kappa PCs, a LCE relapse was diagnosed and the patient started the treatment with bendamustine, bortezomib and dexamethasone. In the present case, the increase of kappa FLC has indicated relapse 4 and 5 months earlier than urine and serum IFE, respectively. Our observation confirms that it is advisable to routinely perform FLC or BJP during follow up of MM patients undergoing ASCT and/or treatment with biological drugs to ensure that LCE is not missed.
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Cadenas kappa de Inmunoglobulina/sangre , Cadenas kappa de Inmunoglobulina/orina , Mieloma Múltiple/diagnóstico , Proteína de Bence Jones/orina , Clorhidrato de Bendamustina/uso terapéutico , Electroforesis de las Proteínas Sanguíneas , Bortezomib/uso terapéutico , Dexametasona/uso terapéutico , Humanos , Inmunoelectroforesis , Inmunoglobulina G/sangre , Inmunoglobulina G/orina , Lenalidomida , Masculino , Persona de Mediana Edad , Mieloma Múltiple/inmunología , Mieloma Múltiple/terapia , Recurrencia , Trasplante de Células Madre , Talidomida/análogos & derivados , Talidomida/uso terapéuticoRESUMEN
Introduction: Recently, a flow cytometric (FC) based test has been developed for detection of circulating fetal cells to replace the less accurate and reproducible Kleihauer-Betke test.FC test is easier to perform, it can distinguish the origin of fetal cells, but it is expensive and available in highly specialized laboratories. We evaluated the introduction of high-performance liquid chromatography (HPLC) approach as initial screening to identify patients who need an additional FC test to better discriminate the nature of haemoglobin-F (HbF) positive cells. Methods: Blood samples from 130 pregnant women suspected to have fetomaternal haemorrhage were analysed with HPLC and FC methods. The cut-off for HbF HPLC concentration was calculated. Statistical analyses for the evaluation of HPLC as a screening method were performed. The positivity cut-off of HbF to be used as decision-making value to continue the investigation was calculated. Results: An excellent agreement (R2 > 0.90) was observed between the percentage of HbF obtained by HPLC and the percentage of fetal cells detected by FC. Results obtained from each assay were compared to define the HPLC threshold below which it is not necessary to continue the investigations, confirming the maternal nature of the HbF positive cells detected. Our study demonstrated that a cut-off of 1.0 % HbF obtained by HPLC was associated with the lowest rate of false negative results in our patient cohort. Conclusions: This study provides a new FMH investigation approach that possibly leads to a reduction in times and costs of the analysis.
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BACKGROUND: Traumatic brain injury (TBI) is one of the major causes of morbidity and mortality worldwide. The patients' and injuries' heterogeneity associated with TBI, alongside with its variable clinical manifestations, make it challenging to make diagnosis and predict prognosis. Therefore, the identification of reliable prognostic markers would be relevant both to support clinical decision-making and forensic evaluation of polytraumatic deaths and cases of medical malpractice. This pilot study aimed to evaluate some of the main biomarkers specific for brain damage in sTBI and mmTBI deaths in samples of vitreous humor (VH) in order to verify whether predictors of prognosis in TBI can be found in this matrix. METHODS: VH were obtained from both eyes (right and left) of 30 cadavers (20 sTBI and 10 mmTBI) and analysed. These factors were evaluated: NSE (neuron-specific enolase), S100 calcium-binding protein (S100), glial fibrillary acidic protein (GFAP), Brain-derived neurotrophic factor (BDNF), Copeptin, Interleukin 6 (IL-6), Ferritin, Lactate dehydrogenase (LDH), C-Reactive Protein (CRP), Procalcitonin (PCT), Glucose and Neutrophil gelatinase-associated lipocalin (N-Gal). RESULTS: Four of the analysed proteins (LDH, ferritin, S100 and NSE) proved to be particularly promising. In particular, logistic regression analysis found a good discriminatory power. CONCLUSIONS: Given the peculiarity of the matrix and the poor standardization of the sampling, such promising results need to be furtherly investigated in serum before being implemented in the forensic practice.
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Lesiones Traumáticas del Encéfalo , Cuerpo Vítreo , Humanos , Proyectos Piloto , Subunidad beta de la Proteína de Unión al Calcio S100 , Lesiones Traumáticas del Encéfalo/diagnóstico , Biomarcadores , Proteína Ácida Fibrilar de la Glía , FerritinasRESUMEN
BACKGROUND & AIMS: Crohn's disease (CD) can develop in any region of the gastrointestinal tract, including the stomach. The etiology and pathogenesis of Crohn's gastritis are poorly understood, treatment approaches are limited, and there are not many suitable animal models for study. We characterized the features and mechanisms of chronic gastritis in SAMP1/YitFc (SAMP) mice, a spontaneous model of CD-like ileitis, along with possible therapeutic approaches. METHODS: Stomachs from specific pathogen-free and germ-free SAMP and AKR mice (controls) were evaluated histologically; the presence of Helicobacter spp was tested in fecal pellets by polymerase chain reaction analysis. In vivo gastric permeability was quantified by fractional excretion of sucrose, and epithelial tight junction protein expression was measured by quantitative reverse-transcription polymerase chain reaction analysis. The effects of a proton pump inhibitor (PPI) or corticosteroids were measured, and the ability of pathogenic immune cells to mediate gastritis was assessed in adoptive transfer experiments. RESULTS: SAMP mice developed Helicobacter-negative gastritis, characterized by aggregates of mononuclear cells, diffuse accumulation of neutrophils, and disruption of epithelial architecture; SAMP mice also had increased gastric permeability compared with controls, without alterations in expression of tight junction proteins. The gastritis and associated permeability defect observed in SAMP mice were independent of bacterial colonization and reduced by administration of corticosteroids but not a PPI. CD4(+) T cells isolated from draining mesenteric lymph nodes of SAMP mice were sufficient to induce gastritis in recipient SCID mice. CONCLUSIONS: In SAMP mice, gastritis develops spontaneously and has many features of CD-like ileitis. These mice are a useful model to study Helicobacter-negative, immune-mediated Crohn's gastritis.
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Enfermedad de Crohn/inmunología , Enfermedad de Crohn/fisiopatología , Gastritis/inmunología , Gastritis/fisiopatología , Corticoesteroides/uso terapéutico , Animales , Enfermedad de Crohn/tratamiento farmacológico , Modelos Animales de Enfermedad , Heces/microbiología , Gastritis/tratamiento farmacológico , Helicobacter/aislamiento & purificación , Ratones , Ratones Endogámicos AKR , Ratones Mutantes , Ratones SCID , Inhibidores de la Bomba de Protones/uso terapéutico , Uniones Estrechas/fisiología , Resultado del TratamientoRESUMEN
We analysed the clinical features and diagnostic workup of patients presenting with haemoptysis to an Italian teaching hospital to derive an easy-to-use clinical score to guide risk stratification and initial management in the emergency department (ED). We retrospectively reviewed clinical records of consecutive patients with haemoptysis over 1 year. A pre-specified set of variables, including demographic data, vital signs, type of expectorate (pure blood vs. blood-streaked sputum), comorbidities, and diagnostic tests and treatments was originally registered. The primary outcome was a composite of any of the following: death from any cause, invasive or non-invasive ventilation, Intensive Care Unit admission, blood transfusions or invasive haemostatic procedures. We investigated associations between the pre-specified clinical variables and the primary outcome using a logistic regression analysis. Finally, we derived a score (the Florence Haemoptysis Score, FLHASc) giving a proportional weight to each variable according to the Odds Ratios (OR). We included 197 patients with a median age of 60 years. The first radiological study was a plain chest X-ray in 128 patients (65%). For 33 (17%) patients, a chest computer tomography (CT scan) was the first radiological study. The most common diagnosis was lung malignancy (19% of cases). The diagnosis remained undetermined in one-third of patients. The primary outcome was met by 11.2% of the study population. Systolic blood pressure <100 mmHg (OR 9.7), a history of malignancy (OR 3), the expectoration of pure blood (OR 2.8), and more than 2 episodes of haemoptysis in the prior 24 h (OR 2.5) are found as independent predictors of the primary outcome. The FLHASc ranges from 0 to 6 with a prognostic accuracy of 78% (IC 95%, 68-88%). The primary outcome incidence is 2.4% (IC 95%, 0.2-8.2%) in patients with a FLHASc equal to zero (n = 85, 43%) versus 13.4% (IC 95% 7.8-21.1%) in patients with a FLHASc > 0 (p < 0.01). Among patients with a FLHASc equal to zero, a negative chest X-ray study identifies patients who may be safely discharged. Patients who presented to the ED with haemoptysis experience a heterogeneous management. We derive a simple clinical prognostic score that may rationalize their diagnostic workup.
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Técnicas de Apoyo para la Decisión , Manejo de la Enfermedad , Hemoptisis/terapia , Adulto , Anciano , Distribución de Chi-Cuadrado , Servicio de Urgencia en Hospital/organización & administración , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Hemoptisis/etiología , Hemoptisis/fisiopatología , Humanos , Incidencia , Italia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Radiografía/métodos , Estudios Retrospectivos , Centros de Atención Terciaria/organización & administración , Centros de Atención Terciaria/estadística & datos numéricos , Triaje/métodos , Triaje/normasRESUMEN
OBJECTIVES: The aim of this study was to determine the reference values for serum cystatin C (CysC) with a particular focus on the effect of aging. DESIGN AND METHODS: The study was performed on a consecutive series of subjects (258 men and 396 women). Laboratory parameters and a detailed personal and family medical history were collected. RESULTS: CysC showed a significant correlation with age in both sexes, which was confirmed with multivariate linear regression after adjustment for SCr (serum creatinine). Age-related reference intervals were established for cystatin C (<45 years, <0.95 mg/L and >45 years, <1.20 mg/L). CONCLUSIONS: The use of CysC reference values adjusted for age should be carefully taken into consideration.
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Cistatinas/sangre , Adulto , Cistatina C , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de ReferenciaRESUMEN
Fractal dimension of pericellular membrane of monocytes was evaluated in diabetic patients and in control subjects. Monocytes were collected from normal healthy volunteers (n = 6) and from diabetic (type 1 and type 2) patients (n = 9). Monocytes from healthy volunteers were also stimulated in vitro with the ionophore A23187 or with the oligopeptide FMLP. Monocytes, obtained by Ficoll-Hypaque, were examined with a Philips 300 transmission electron microscope. The cell contour was extracted, resized to a standard dimension and converted to a single pixel outline. Box-counting method was then applied to determine the fractal dimension. Fractal dimensions of monocytes appeared statistically increased in diabetic patients (type 1 and type 2), compared with sex- and age-matched controls (p < 0.01, p < 0.01). The mechanism underlying the observed increased complexity of pericellular membrane may be explained by the in vivo activation of the circulating monocyte in diabetes. In effect, fractal analysis of stimulated in vitro monocytes showed a significant increase of complexity of pericellular membrane, compared with their controls (p < 0.001). Our approach was able to assess and quantitatively evaluate in diabetic patients morphological modifications of the monocyte linked to its activation, offering new parameters useful to follow the effects of therapeutical procedures.
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Membrana Celular/efectos de los fármacos , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 2/sangre , Monocitos/ultraestructura , Membrana Celular/ultraestructura , Femenino , Fractales , Humanos , Ionóforos/farmacología , Masculino , Microscopía Electrónica de Rastreo/métodos , Monocitos/efectos de los fármacos , N-Formilmetionina Leucil-Fenilalanina/farmacología , Estadísticas no ParamétricasRESUMEN
BACKGROUND AND AIMS: Liver inflammation is a common extraintestinal manifestation of inflammatory bowel disease (IBD); however, whether liver involvement is a consequence of a primary intestinal defect or results from alternative pathogenic processes remains unclear. Therefore, we sought to determine the potential pathogenic mechanism(s) of concomitant liver inflammation in an established murine model of IBD. METHODS: Liver inflammation and immune cell subsets were characterized in ileitis-prone SAMP1/YitFc (SAMP) and AKR/J (AKR) control mice, lymphocyte-depleted SAMP (SAMPxRag-1-/-), and immunodeficient SCID recipient mice receiving SAMP or AKR donor CD4+ T-cells. Proliferation and suppressive capacity of CD4+ T-effector (Teff) and T-regulatory (Treg) cells from gut-associated lymphoid tissue (GALT) and livers of SAMP and AKR mice were measured. RESULTS: Surprisingly, prominent inflammation was detected in 4-wk-old SAMP livers, prior to histologic evidence of ileitis, while both disease phenotypes were absent in age-matched AKRs. SAMP liver disease was characterized by abundant infiltration of lymphocytes, required for hepatic inflammation to occur, a Th1-skewed environment, and phenotypically-activated CD4+ T-cells. SAMP intrahepatic CD4+ T-cells also had the ability to induce liver and ileal inflammation when adoptively transferred into SCID recipients, whereas GALT-derived CD4+ T-cells produced milder ileitis, but not liver inflammation. Interestingly, SAMP intrahepatic CD4+ Teff cells showed increased proliferation compared to both SAMP GALT- and AKR liver-derived CD4+ Teff cells, while SAMP intrahepatic Tregs were decreased among CD4+ T-cells and impaired in in vitro suppressive function compared to AKR. CONCLUSIONS: Activated intrahepatic CD4+ T-cells induce liver inflammation and contribute to experimental ileitis via locally-impaired hepatic immunosuppressive function.
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Aberrations of genes/proteins regulating cell cycle and growth, increased proliferation and telomerase activity (TA) are documentable in glioblastoma multiforme. TA is more frequently detectable in secondary glioblastoma, which is also characterized by p53 mutation/overexpression. Discordant telomere (Te) length values have been reported in glioblastomas with and without TA. In 31 glioblastomas, in which pre-existing astrocytoma was not documented, we compared cases with and without TA for the expression of p53, EGFR, c-Myc, MIB-1 and Topoisomerase IIalpha; p53 mutations were also investigated by SSCP-PCR. Correlations were made with Te parameters [TePs: number (TeNo), length and area] as evaluated by image analysis in interphase nuclei of fluorescence in situ hybridization (FISH)-processed sections. We found no differences in the expression of the proteins evaluated and in TePs, except Te/nuclear area %, which was significantly lower in TA+ cases (p=0.02). TePs were, instead, inversely correlated with TA (p=0.0001). TA was positively correlated with MIB1 staining index in the TA+ cases (p=0.033), which also showed a positive correlation between TeNo and EGFR expression (p=0.042), and a trend towards a negative correlation between TeNo and p53 expression (p=0.05). Tumors overexpressing EGFR had a significantly shorter lifetime (p=0.0001). TeNo seems to be inversely correlated to tumor proliferation and lifetime in glioblastoma multiforme.
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Glioblastoma/enzimología , Hibridación Fluorescente in Situ/métodos , Telomerasa/metabolismo , Telómero/ultraestructura , Fosfatasa Ácida/metabolismo , Adolescente , Adulto , Antígenos de Neoplasias , Neoplasias Encefálicas/enzimología , División Celular , Niño , ADN-Topoisomerasas de Tipo II/metabolismo , Proteínas de Unión al ADN , Receptores ErbB/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Isoenzimas/metabolismo , Antígeno Ki-67/biosíntesis , Antígeno Ki-67/metabolismo , Persona de Mediana Edad , Polimorfismo Conformacional Retorcido-Simple , Proteínas Proto-Oncogénicas c-myc/metabolismo , Fosfatasa Ácida Tartratorresistente , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
BACKGROUND: Hemoglobin A1c (HbA1c) measurement is currently used for the routine monitoring of long-term glycemic status, thus playing a fundamental role in the management of this disease. Since this marker has recently been recommended as an additional tool for diagnosing diabetes, it's of the utmost importance to ensure that the precision and accuracy of HbA1c methods are satisfactory. METHODS: We assessed the analytical performances of the Capillarys 2 Flex Piercing® analyzer and compared the results obtained with those from two other widely used HPLC instruments. Furthermore, we evaluated the convenience and ergonomics of the system in authentic routine work conditions in three centers. RESULTS: Within-laboratory (n=40) and between-laboratory (n=120) imprecision CV% using four blood samples with different concentrations of HbA1c were <3.4% and <3.1% using IFCC units and <2.1% and <2.0% using NGSP units, respectively. The obtained trueness (<3 mmol/mol, <0.3%) was highly satisfactory, nor was HbA1c measurement compromised by the presence of the commonly present hemoglobinopathies. The comparison made with established methods revealed excellent agreement (r>0.985). CONCLUSIONS: The evaluated method is precise, accurate and robust, with a high throughput. It also allows the identification of the most frequent Hb variants and therefore may be a valid alternative to other methods currently proposed for routine use in clinical laboratories.
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Diabetes Mellitus/diagnóstico , Hemoglobina Glucada/metabolismo , Talasemia beta/sangre , Automatización de Laboratorios , Biomarcadores/sangre , Diabetes Mellitus/sangre , Electroforesis Capilar , Hemoglobina Fetal/metabolismo , Hemoglobina A2/metabolismo , Humanos , Variaciones Dependientes del Observador , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Human hepatic stellate cells have been shown to be resistant to apoptotic stimuli. This is likely dependent on the activation of anti-apoptotic pathways upon transition of these cells to myofibroblast-like cells. In particular, previous studies have demonstrated an increased expression of the anti-apoptotic protein Bcl-2 and a decreased expression of the pro-apoptotic protein Bax during the transition of the hepatic stellate cell phenotype from quiescent to myofibroblast-like cells. However, the role and expression of other key anti-apoptotic and survival pathways elicited by polypeptide growth factors involved in the chronic wound healing process remain to be elucidated. In particular, insulin growth factor-I promotes chemotactic and mitogenic effects in activated human hepatic stellate cells and these effects are mediated by the activation of PI 3-K. The role of insulin growth factor-I as a survival factor in human hepatic stellate cells needs to be substantiated. The aim of this study was to evaluate the involvement of other key anti-apoptotic pathways such as PI-3K/Akt/p-Bad in response to insulin growth factor-I. RESULTS: Insulin growth factor-I induced activation of Akt followed by Bad phosphorylation after 15 minutes of incubation. These effects were PI-3k dependent since selective inhibitors of this molecule, wortmannin and LY294002, inhibited both Akt and Bad phosphorylation. The effect of insulin growth factor-I on the activation of two downstream targets of Akt activation, that is, GSK3 and FHKR, both implicated in the promotion of cell survival was also investigated. Both targets became phosphorylated after 15 minutes of incubation, and these effects were also PI-3K-dependent. Despite the activation of this survival pathway insulin growth factor-I did not have a remarkable biological effect, probably because other insulin growth factor-I-independent survival pathways were already maximally activated in the process of hepatic stellate cell activation. However, after incubation of the cells with a strong apoptotic stimuli such as Fas ligand+cycloheximide, a small percentage of hepatic stellate cells underwent programmed cell death that was partially rescued by insulin growth factor-I. CONCLUSION: In addition to Bcl-2, several other anti-apoptotic pathways are responsible for human hepatic stellate cell resistance to apoptosis. These features are relevant for the progression and limited reversibility of liver fibrosis in humans.
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The insulin-sensitising adipose hormone adiponectin is reduced in type 2 diabetic patients. We assessed the relationships between plasma adiponectin and chronic hyperglycaemia. Adiponectin levels and glycated haemoglobin (HbA1c) were measured at enrolment and after 90 days in 16 patients with type 2 diabetes aged (mean +/- SEM) 63.0 +/- 0.6 years, with body mass index (BMI) 30.2 +/- 0.5 kg/m2 and HbA1c concentration 7.4 +/- 0.1%, who did not modify their hypoglycaemic treatment during the observation period. Furthermore, plasma adiponectin was measured in 29 adult patients with type 1 diabetes and compared with 29 control subjects matched for sex, age, BMI, waist circumference and bioimpedance-estimated fat mass. In type 2 diabetic patients at enrolment, adiponectin concentration correlated with BMI (r = -0.46; p < 0.05), but not with HbA1c. During the prospective observation, variations of adiponectin showed a significant correlation with variations of BMI (r = -0.47; p < 0.01), but not with variations of HbA1c concentration. These results were confirmed by multivariate analysis after adjustment for sex and age. Adiponectin levels in type 1 diabetic patients (380.8 +/- 13.7 ng/ml in women, 192.5 +/- 13.9 ng/ml in men) were significantly (p < 0.05) higher than in control subjects (277.6 +/- 11.0 ng/ml in women, 102.7 +/- 5.1 ng/ml in men); plasma adiponectin correlated significantly with BMI and waist circumference, but not with HbA1c. In conclusion, the reduction of plasma adiponectin levels in type 2 diabetic patients does not appear to be determined by chronic hyperglycaemia. Adiponectin levels are increased in type 1 diabetes, but this phenomenon is not attributable to differences in nutritional status or body composition.