Bioengineered Cartilage in a Scaffold‐Free Method by Human Cartilage‐Derived Progenitor Cells: A Comparison With Human Adipose‐Derived Mesenchymal Stromal Cells

The objective of our study was to investigate chondrogenesis potential of human adipose‐derived mesenchymal stromal cells (MSCs), using as a positive control a human source of cartilage‐derived progenitor cells (PCs). This source of PCs was recently described by our group and dwells on the surface of nasoseptal cartilage. Histological analysis using Safranin O staining and immunofluorescence for actin filaments and collagen type II was performed on three‐dimensional (3D) pellet cultures. Cartilage PCs and adipose MSCs showed similarities in monolayer culture related to cell morphology and proliferation. Our 3D pellet cultures substantially reduced the actin stress and after 21 days under chondrogenic medium, we observed an increase in the pellet diameter for cartilage PCs (7.4%) and adipose MSCs (21.2%). Adipose‐derived MSCs responded to chondrogenic stimulus, as seen by positive areas for collagen type II, but they were not able to recreate a mature extracellular matrix. Using semi‐quantitative analysis, we observed a majority of Safranin O areas rising from blue (no stain) to orange (moderate staining) and no changes in fibroblastic morphology (P < 0.0001). For cartilage PCs, chondrogenic induction is responsible for morphological changes and a high percentage of matrix area/number of cells (P ≤ 0.0001), evaluated by computerized histomorphometry. Morphological analyses reveal that adipose‐derived MSCs were not able to recreate a bioengineered cartilage. The cost of culture was reduced, as the cartilage PCs under growth‐factor free medium exhibit a high score for cartilage formation compared with the induced adipose mesenchymal stromal cells (P = 0.0021). Using a pellet 3D culture, our cartilage PCs were able to produce a cartilage tissue in vitro, leading to the future development of bioengineered products.     

Serum cystatin C as an endogenous marker of renal function in patients with mild to moderate impairment of kidney function.

BACKGROUND: Estimation of the glomerular filtration rate (GFR) is essential for the evaluation of patients with chronic kidney disease (CKD). Recently, serum cystatin C was proposed as a new endogenous marker of GFR and in our study its diagnostic accuracy was compared with that of other markers of GFR. METHODS: In this study, 164 patients with CKD stages 2-3 (GFR 30-89 ml/min/1.73 m2), who had performed 51Cr-labelled ethylenediaminetetra-acetic acid clearance, were enrolled. In each patient, serum creatinine and serum cystatin C were determined. Creatinine clearance was calculated using the Cockcroft-Gault (C&G) and the modification of diet in renal disease (MDRD) formulas. RESULTS: The mean 51CrEDTA clearance was 57 ml/min/1.73 m2, the mean serum creatinine 149 micromol/l and the mean serum cystatin C 1.74 mg/l. We found significant correlation between 51CrEDTA clearance and serum creatinine (R = -0.666), serum cystatin C (R = -0.792), reciprocal of serum creatinine (R = 0.628), reciprocal of serum cystatin C (R = 0.753) and calculated creatinine clearance from the formulas C&G (R = 0.515) and MDRD formulas (R = 0.716). The receiver operating characteristic (ROC) curve analysis (cut-off for GFR 60 ml/min/1.73 m2) showed that serum cystatin C had a significantly higher diagnostic accuracy than serum creatinine (P = 0.04) and calculated creatinine clearance from the C&G formula (P < 0.0001), though only in female patients. No difference in diagnostic accuracy was found between serum cystatin C and creatinine clearance calculated from the MDRD formula. CONCLUSIONS: Our results indicate that serum cystatin C is a reliable marker of GFR in patients with mildly to moderately impaired kidney function and has a higher diagnostic accuracy than serum creatinine and calculated creatinine clearance from the C&G formula in female patients.     

Asymptomatic atherosclerosis and hypertension in nondiabetic patients with chronic kidney disease

Abstract:  Atherosclerosis is accelerated in dialysis patients, but less is known about asymptomatic atherosclerosis and major risk factors in patients with different stages of chronic kidney disease (CKD). We compared intima media thickness (IMT) and plaque occurrence in the carotid arteries in 104 nondiabetic patients (stages 1–5 of CKD; mean age: 51.6 years) with those in 40 healthy control subjects. The IMT values (0.69 vs. 0.59 mm; P  < 0.002) were higher in patients. More patients had plaques (46.2 vs. 17.5%; P  < 0.002), and number of plaques was higher ( P  < 0.003). Negative correlation between IMT ( P  < 0.0001), presence of plaques ( P  < 0.0001), their number ( P  < 0.040), and chromium 51-labeled ethylenediaminetetraacetate (⁵¹Cr-EDTA) clearance were found in patients. With multiple regression analysis, relationship between IMT and ⁵¹Cr-EDTA clearance ( P  < 0.001) and presence of hypertension ( P  < 0.001) was found. Nondiabetic patients with CKD showed advanced atherosclerosis and IMT, plaque occurrence, and number increased directly with the level of renal dysfunction. Another important risk factor was hypertension.       

Quantitative determination of magnetic force on a coronary stent in MRI

Purpose:

To introduce an analytical method for a quantitative determination of magnetic force on a coronary stent in the magnetic resonance imaging (MRI) magnet that is generally applicable to metallic implants. Magnetic forces on metallic implants in the MRI magnets are traditionally determined empirically by measuring deflection from the vertical plane at the central axis of the magnet and at the point of the largest force along the longitudinal axis of the magnet.

Materials and Methods:

Magnetic and chemical characterization of the stents was performed by a commercial magnetometer and energy‐dispersive X‐ray spectroscopy. Magnetic force on the stents fabricated of paramagnetic alloys (surgical stainless steel and cobalt–chromium) was determined by measuring the stent's magnetic dipole moment and employing the on‐axis magnetic field profile of an MRI magnet.

Results:

The maximum force on the stainless steel stent was found to be F_S,max = 0.18 mN, whereas on the cobalt–chromium stent it was F_C,max = 0.06 mN.

Conclusion:

The magnetic force on the investigated paramagnetic stents is even smaller than the gravitational force acting on the stents in the Earth's gravity field, so that it has no physiological impact on the stented vessels. J. Magn. Reson. Imaging 2013;37:391–397. © 2012 Wiley Periodicals, Inc.     

Aetiology and outcome of acute renal failure secondary to war related trauma and infectious disease in Croatia

Summary: The aim of our study was to explore the aetiology and the outcome of acute renal failure (ARF) during the war in Croatia. of the 2132 patients admitted to our hospital between April 1990 and November 1992 due to war related trauma, 11 (0.5%) developed ARF. We believe that the development of ARF in these patients was secondary to an overwhelming septic process. Most of our patients suffered from multiple organ failure. of the 11 patients suffering from ARF due to war related trauma only four recovered (63.6% had died). We attribute the lethal outcome to the progression of the septic process. Patients who developed ARF due to infectious diseases unrelated to trauma had a different prognosis. Acute renal failure caused by the Hantan virus ran a benign course, in both its oliguric and non-oliguric form. Patients who developed ARF as a complication of leptospirosis also had a good prognosis. Although ARF is usually of a multifactorial genesis, our study aimed to emphasize the importance of disseminated septic processes as a cause of ARF.     

Plasma membrane and vesicular monoamine transporters in normal endometrium and early pregnancy decidua

The uterus is innervated by adrenergic sympathetic fibres, and the endometrium has a capability for endogenous monoamine synthesis. Extracellular monoamine levels are regulated primarily through re-uptake by specific membrane-bound transporter proteins dopamine transporter (DAT), norepinephrine transporter (NET) and serotonin transporter (SERT). Intracellular storage of monoamines involves vesicular transporter proteins (VMAT1 and VMAT2). This study explored gene expression of the monoamine transporters in normal endometrium throughout the menstrual cycle and early decidua. In-situ hybridization histochemistry revealed three general classes of expression patterns: (i). epithelial expression of NET mRNA; (ii). increasing stromal expression of VMAT2 mRNA in the proliferative phase; and (iii). increasing epithelial expression of VMAT2 mRNA during the secretory phase. Real time PCR showed low expression levels of NET in all phases of the endometrial cycle and a higher expression of VMAT2 mRNA in the mid-secretory phase. Our results suggest that several monoamine transporters may have menstrual cycle phase-specific functions in endometrial biology by maintaining adequate levels of monoamines. Re-uptake and regulated release of monoamines may also modulate several steps of the reproductive processes such as embryo implantation and decidua formation.     

BMLA Annual Meeting 2006 Late Arriving Abstracts

Late Abstracts

BMLA Annual Meeting 2006 Late Arriving Abstracts