The small Rho GTP-binding proteins are important cell morphology, function, and apoptosis regulators. Unlike other Rho proteins, RhoB can be subjected to either geranylgeranylation (RhoB-GG) or farnesylation (RhoB-F), making that the only target of the farnesyltransferase inhibitor (FTI). Fluorescence resonance energy transfer experiments revealed that RhoB is activated by hyperosmolarity.
View Article and Find Full Text PDFMetabolic syndrome (MetS) is a combination of metabolic disorders that concurrently act as factors promoting systemic pathologies such as atherosclerosis or diabetes mellitus. It is now believed to encompass six main interacting conditions: visceral fat, imbalance of lipids (dyslipidemia), hypertension, insulin resistance (with or without impairing both glucose tolerance and fasting blood sugar), and inflammation. In the last 10 years, there has been a progressive interest through scientific research investigations conducted in the field of metabolomics, confirming a trend to evaluate the role of the metabolome, particularly the intestinal one.
View Article and Find Full Text PDFNephrogenic syndrome of inappropriate antidiuresis (NSIAD) is a rare X-linked disease caused by gain-of-function mutations of arginine vasopressin receptor 2 (V2R). Patients with NSIAD are characterized by the inability to excrete a free water load and by inappropriately increased urinary osmolality despite very low levels of plasma vasopressin, resulting in euvolaemic hyponatraemia. To dissect the signalling downstream V2R constitutively active variants, Flp-In T-REx Madin-Darby canine kidney (FTM) cells, stably transfected with V2R mutants (R137L, R137C and F229V) and AQP2-wt or non-phosphorylatable AQP2-S269A/AQP2-S256A, were used as cellular models.
View Article and Find Full Text PDFVasopressin (AVP) plays a key function in controlling body water and salt balance through the activation of the vasopressin receptors V1aR and V2R. Abnormal secretion of AVP can cause the syndrome of inappropriate antidiuresis that leads to hyponatremia, which is an electrolyte disorder often observed in the elderly hospitalized and oncologic patients. Beyond kidneys, the colonic epithelium modulates water and salt homeostasis.
View Article and Find Full Text PDFRenal collecting duct principal cells play a key role in controlling body water balance. Principal cells express the water channels AQP2, AQP3, and AQP4 that mediate renal water reabsorption. AQP3 and AQP4 are expressed at the basolateral membrane constitutively.
View Article and Find Full Text PDFExposure to actual or simulated microgravity results in alterations of renal function, fluid redistribution, and bone loss, which is coupled to a rise of urinary calcium excretion. We provided evidence that high calcium delivery to the collecting duct reduces local Aquaporin 2 (AQP2)-mediated water reabsorption under vasopressin action, thus limiting the maximal urinary concentration to reduce calcium saturation. To investigate early renal adaptation into simulated microgravity, we investigated the effects of 10 days of strict bedrest in 10 healthy volunteers.
View Article and Find Full Text PDFVasopressin (AVP) increases water permeability in the renal collecting duct through the regulation of aquaporin-2 (AQP2) trafficking. Several disorders, including hypertension and inappropriate antidiuretic hormone secretion (SIADH), are associated with abnormalities in water homeostasis. It has been shown that certain phytocompounds are beneficial to human health.
View Article and Find Full Text PDFNSIAD is a rare X-linked condition, caused by activating mutations in the gene coding for the vasopressin V2 receptor (V2R) associated with hyponatremia, despite undetectable plasma vasopressin levels. We have recently provided in vitro evidence that, compared to V2R-wt, expression of activating V2R mutations R137L, R137C and F229V cause a constitutive redistribution of the AQP2 water channel to the plasma membrane, higher basal water permeability and significantly higher basal levels of p256-AQP2 in the F229V mutant but not in R137L or R137C. In this study, V2R mutations were expressed in collecting duct principal cells and the associated signalling was dissected.
View Article and Find Full Text PDFDietary habits are crucially important to prevent the development of lifestyle-associated diseases. Diets supplemented with chickpeas have numerous benefits and are known to improve body fat composition. The present study was undertaken to characterize two genetically and phenotypically distinct accessions, MG_13 and PI358934, selected from a global chickpea collection.
View Article and Find Full Text PDFVasopressin V2 receptor (V2R) antagonists (vaptans) are a new generation of diuretics. Compared with classical diuretics, vaptans promote the excretion of retained body water in disorders in which plasma vasopressin concentrations are inappropriately high for any given plasma osmolality. Under these conditions, an aquaretic drug would be preferable over a conventional diuretic.
View Article and Find Full Text PDFCadmium (Cd) is a heavy and highly toxic metal that contaminates air, food and water. Cadmium accumulates in several organs altering normal functions. The kidney is the major organ at risk of damage from chronic exposure to cadmium as a contaminant in food and water.
View Article and Find Full Text PDFAutosomal Dominant Polycistic kidney Disease (ADPKD) is a renal channelopathy due to loss-of-function mutations in the or genes, encoding polycystin-1 (PC1) or polycystin-2 (PC2), respectively. PC1 is a large protein found predominantly on the plasma membrane where interacts with different proteins, including PC2. PC2 is a smaller integral membrane protein also expressed in intracellular organelles, acting as a non-selective cation channel permeable to calcium.
View Article and Find Full Text PDFBackground: The aim of our study was to improve the detection of HCC by measuring alpha-fetoprotein (AFP) in addition to other molecular markers by estimating the plasma concentration of transforming growth factor beta (TGF-β) and epidermal growth factor receptor (EGFR). In particular, the role of hepatitis C and B viruses (HCV and HBV) infection was evaluated with relation to TGF-β and EGFR plasma concentration.
Materials And Methods: Eighty-five patients with liver disease, 54 with hepatocellular carcinoma (HCC), 16 with liver metastasis (LM), 15 with liver cirrhosis (LC) and 30 healthy volunteers were evaluated.
Background: There is increasing evidence on cerebrospinal fluid (CSF) oligoclonal IgM (OCIgM) predicting a more aggressive disease course in relapsing-remitting Multiple Sclerosis (MS), while there is a scarcity of data for primary progressive MS (PPMS).
Objective: Our aim was to investigate the presence and possible prognostic value of CSF OCIgM in a group of PPMS and in a group of relapsing-onset MS patients. The possible prognostic role of other clinical and biological factors was also evaluated.
J Thorac Cardiovasc Surg
December 2008
Background: Anticoagulation therapy with heparin induces antibodies that recognize multimolecular complexes of platelet factor 4 bound to heparin (anti-platelet factor 4/heparin antibodies). Considering that cardiac surgery induces an intense platelet activation and proinflammatory response, we examined the relationship between formation of anti-platelet factor 4/heparin antibodies and plasma levels of platelet factor 4 and interleukin 6. We also examined the relationship between anti-platelet factor 4/heparin seroconversion and the histocompatibility leukocyte antigen system.
View Article and Find Full Text PDFAims And Background: The epidermal growth factor receptor (EGFR) is a member of a family of cell membrane receptors that use tyrosine kinase activity as the signal transduction mechanism. It is commonly expressed or overexpressed by many solid tumors and correlates with disease progression and a poor clinical prognosis. Increased EGFR expression might therefore be a strong prognostic feature in multiple tumor types, and inhibition of its cellular actions may have substantial therapeutic benefit.
View Article and Find Full Text PDFAims And Background: The aims of this study were to assess the clinical utility of circulating preoperative HER-2 extracellular domain p105 detected by enzyme immunoassay (ELISA), to compare the tissue expression of HER-2/neu determined by immunohistochemistry (IHC), to correlate prognostic factors including tumor size, nodal involvement, and hormone receptor status, and to analyze the prognostic significance of the marker in relation to clinical outcome as measured by disease-free and overall survival.
Methods: In this study, we enrolled 108 consecutive patients with breast carcinoma, and obtained serum samples and frozen tumor tissues. We compared them with 57 women with fibroadenoma and 63 healthy women as controls.
Objective: The activation of the coagulation and fibrinolytic systems and platelet function in patients undergoing coronary artery bypass surgery on-pump or off-pump techniques was compared.
Methods: Thirty-two patients were randomly assigned to on-pump or off-pump coronary artery bypass grafting. Heparin was given at the same dose.
Cardiopulmonary bypass (CPB) induces hemolysis and the activation of the inflammatory and coagulation systems. Several components of the CPB equipment may contribute to such phenomenon. We tested the effects of two differently designed centrifugal pumps (Bio-Pump, Medtronic and Revolution, Cobe) on several markers of hemolysis, coagulation, and inflammation: plasma free hemoglobin,prothrombin fragment 1.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
April 2004
The effect of three storage temperature levels (i.e. +4, -20 and -80 degrees C) and time intervals from sampling (3, 6 and 9 months) on the degradation of 3,4-dihydroxyphenylglycol (DHPG) and norepinephrine (NE) was investigated in a systematic study.
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