Quasi-3D morphology and modulation of focal adhesions of human adult stem cells through combinatorial concave elastomeric surfaces with varied stiffness.

In vivo cell niches are complex architectures that provide a wide range of biochemical and mechanical stimuli to control cell behavior and fate. With the aim to provide in vitro microenvironments mimicking physiological niches, microstructured substrates have been exploited to support cell adhesion and to control cell shape as well as three dimensional morphology. At variance with previous methods, we propose a simple and rapid protein subtractive soft lithographic method to obtain microstructured polydimethylsiloxane substrates for studying stem cell adhesion and growth. The shape of adult renal stem cells and nuclei is found to depend predominantly on micropatterning of elastomeric surfaces and only weakly on the substrate mechanical properties. Differently, focal adhesions in their shape and density but not in their alignment mainly depend on the elastomer stiffness almost regardless of microscale topography. Local surface topography with concave microgeometry enhancing adhesion drives stem cells in a quasi-three dimensional configuration where stiffness might significantly steer mechanosensing as highlighted by focal adhesion properties.

Proteinuria in the prognosis of IgA nephropathy.

IgA Nephropathy (IgAN) is the most common lesion causing primary glomerulonephritis in the world. The main clinical predictors of progression are: elevated blood pressure, high histological score and proteinuria. Although elevated serum creatinine concentration at diagnosis, increased excretion of cytochines, age at onset, obesity and genetic factors may all influence clinical outcome, it is quite clear that proteinuria is the hallmark of renal damage in IgAN. Patients with IgAN and little or no proteinuria (<500 mg/day) have low risk of progression in the short term, while the rate of decline in renal function is 25-fold faster in those with sustained proteinuria >3 g/day. The product of duration (years) and urinary protein excretion (g/day) at the time of renal biopsy is more significantly correlated with progression. So, this so called proteinuria index may be a useful predictor for glomerular and interstitial histopathological changes and the fate of renal function in IgAN. The progression of IgAN may be slowed by antihypertensive and antiproteinuric therapy, such as angiotensin converting enzyme inhibitors and/or angiotensin II receptor blockers, that can minimize secondary glomerular injury. Proteinuria has been shown to be an adverse prognostic factor in IgAN, with a strong relationship between proteinuria and prognosis and established importance of remission. Consequently, targeting proteinuria may be a valid surrogate for individualized kidney protective therapy.

[Proteomics and the kidney: an innovative approach to the study of renal disease]. / Proteomica e rene: un approccio innovativo allo studio delle malattie renali.

In the post human genome era, several ''omics'' fields are emerging. Proteomics has experienced a rapid growth in the recent past and has great potential for the future. Proteomic technologies are used with increasing frequency also in nephrology. The aim of this review is to examine the recent application of emerging proteomic technologies to the study of renal physiology and pathophysiology. We highlight the use in renal research of a number of available techniques including 2-dimensional gel electrophoresis, liquid chromatography/mass spectrometry, surface-enhanced laser desorption/ionization, and capillary electrophoresis/mass spectrometry. We examine the role, efficacy and diagnostic potential of the different proteomic approaches, focusing on current difficulties and potential solutions. The integrating role of bioinformatics and the need for standardized procedures for sample preservation and analysis and reporting of results are also discussed. Although the field is still in an embryonic stage, the knowledge gained up to now is important not only for a better understanding of renal physiology and pathophysiology, but also for the identification of disease markers and the development and follow-up of new therapies. This review gives an overview of proteomics, providing background information, outlining the scopes, highlighting the applications in nephrology, and reporting advantages and limitations.

[Biofilters and biosensors]. / Biofiltri e biosensori.

Sepsis is the leading cause of morbidity and mortality in intensive care units (ICU). Acute renal failure (ARF) is a common condition, affecting approximately 5% of all hospitalized patients and up to 20% of critically ill patients. The combination of ARF and sepsis is associated with 75% mortality. Hyperglycemia and an increase in plasma lactate concentration are markers of poor prognosis in patients with sepsis; they often precede the onset of multiple organ dysfunction and ARF. Direct online measurement by means of amperometric biosensors would allow the early detection of increasing levels of both glucose and lactate, as well as the possibility to maintain glucose within a well-defined range. Current standards of care in ARF require synthetic membranes that substitute the small solute clearance function of the renal glomerulus, but they do not replace the transport, metabolic and endocrine functions of the renal proximal tubule cells. The application of cell therapy to the successful process of hemofiltration may therefore improve the poor prognosis of patients with ARF in the ICU. An extracorporeal bioartificial kidney consisting of a conventional hemofilter connected to a renal tubule assist device has demonstrated both in animal models of ARF and in phase I/II clinical trials its ability to successfully replace the filtration, transport, metabolic, and endocrine functions of the kidney. To improve the outcome of septic patients with ARF, multidisciplinary interactions and cooperation between basic, clinical and industrial researchers are mandatory; the development of new artificial or biological devices may allow online monitoring of biological parameters and better treatment of septic syndrome and related systemic complications.

[Chemokines: possible therapeutic targets and useful clinical parameters in renal transplantation]. / Le chemochine nel trapianto renale: possibili bersagli terapeutici e nuovi parametri clinici.

Chemokines are a family of small, structurally related cytokines that regulate trafficking of different subsets of leukocytes, thus critically regulating inflammation. The chemokine system influences allograft biology at 3 main levels: 1) the process of ischemia-reperfusion injury, 2) the induction of transplant tolerance, and 3) the pathogenesis of acute rejection and chronic allograft nephropathy. Accordingly, following ischemia/reperfusion in a rat model, CXCR2 produced at the graft level attracts and activates granulocytes, which in turn promotes graft damage. Moreover, in some experimental models CCR4 recruits T regulatory cells and mediates transplant tolerance. Furthermore, the discovery of the involvement of CXCR3 in the induction of the alloresponse to transplant suggests that this chemokine receptor might represent an important target for treatment of both acute rejection and chronic allograft nephropathy. Indeed, CXCR3 ligands play a pivotal role in the initiation and amplification of host alloresponses and also alter vascular cell functions, which explains their critical role not only in the development of acute rejection, but also in the pathogenesis of chronic allograft nephropathy, where both immune- and nonimmune- mediated mechanisms are involved. Finally, we have recently demonstrated that the pretransplant serum level of the CXCR3 ligand IP-10/CXCL10 is a clinically useful parameter for the identification of subjects with a high risk of acute rejection, chronic allograft nephropathy, and graft failure. This simple test could contribute to the prevention of acute rejections and the individualization of immunosuppressive therapies.

[Renal neoplasms and renal transplantation: current problems and future perspectives]. / Neoplasie renali e trapianto di rene: problematiche attuali e prospettive future.

Primary carcinomas of the kidney can develop in renal transplantation in four sets of circumstances: (1) detected in the donor, (2) detected as a pre-existing neoplasm in the recipient prior to transplantation, (3) as de novo malignancies arising post-transplantation in the native kidneys of the recipient, (4) or in the graft. In Italy, any renal mass detected during harvesting does not allow the use of any organs for transplantation; however, several reports from other countries have already shown the safety and efficacy of transplanting kidneys with small (<4 cm), unifocal, subcapsular tumors, after resecting the lesion at the back table and verifying the negativity of the surgical margins; this strategy could also be evaluated in Italy to expand the donor pool. Acquired cystic kidney disease (ACKD) is commonly observed in uremic patients undergoing chronic hemodialysis (HD); numerous studies have reported an increased prevalence of renal cell carcinoma (RCC) in association with this nephropathy. The use of ultrasound, computerized axial tomography (CAT) and magnetic resonance imaging (MRI) has greatly improved the ability to detect renal tumors at earlier stages associated with ACKD and the morbidity and mortality rate, in either uremic or transplant patients. RCC in the transplanted kidney is rare and, when recognized, requires nephrectomy. However, a conservative approach with nephron sparing surgery has been reported for selected cases as a useful strategy to treat renal carcinoma in the allograft.

[Nutcracker syndrome: a difficult case of recurrent gross hematuria]. / Sindrome di nutcracker: una macroematuria intermittente di difficile diagnosi.

BACKGROUND: The Nutcracker Syndrome (NS) is an uncommon clinical condition caused by compression and entrapment of the renal vein (LRV) as it passes through the angle between the superior mesenteric artery (SMA) and the aorta (meso-aortic angle). Intermittent macrohematuria, left peripelvic and gonadal vein varices and aspecific abdominal pain may be common manifestations of this syndrome. CASE-REPORT: A 15-year-old white boy developed recurrent macrohaematuria in June 2002. He had a history of upper respiratory infection prior the first episode of gross hematuria followed by 4 other episodes of macrohematuria 'sine causa'. Blood pressure and renal function were normal. Routine laboratory tests showed only an increase in serum LDH levels (901 IU/L) with negative Coombs' test, both direct and indirect, and absence of schistocytes in the blood smear. Renal ultrasonography showed normal kidneys while an intravenous pyelography showed a 'minus' in the right ureter. For this reason, a cystoscopy and a retrograde pielography were performed but resulted normal. A renal biopsy was carried out because of the presence of one episode of post-infective macrohaematuria, but light microscopy and immunofluorescence examinations were found to be normal. Renal ultrasonography and Color Doppler ultrasonography (CD-USG) oriented our diagnosis towards NS. An abdominal computerised tomography (CT) scan confirmed that the LRV was compressed between the aorta and the SMA. CONCLUSIONS: NS cannot be diagnosed with routine diagnostic methods. Endoscopic and radiological methods may provide some clues for the presence of NS, while CD-USG may be considered to be the first level non-invasive method for diagnosis. The sensitivity and specificity of this test for diagnosing NS is reported as being 78% and 94%, respectively. The best treatment available for this syndrome is still being debated.