Biomechanical And Histological Evaluation Of Hydrogel Implants In Articular Cartilage.

We evaluated the mechanical behavior of the repaired surfaces of defective articular cartilage in the intercondylar region of the rat femur after a hydrogel graft implant. The results were compared to those for the adjacent normal articular cartilage and for control surfaces where the defects remained empty. Hydrogel synthesized by blending poly(2-hydroxyethyl methacrylate) and poly(methyl methacrylate-co-acrylic acid) was implanted in male Wistar rats. The animals were divided into five groups with postoperative follow-up periods of 3, 5, 8, 12 and 16 weeks. Indentation tests were performed on the neoformed surfaces in the knee joint (with or without a hydrogel implant) and on adjacent articular cartilage in order to assess the mechanical properties of the newly formed surface. Kruskal-Wallis analysis indicated that the mechanical behavior of the neoformed surfaces was significantly different from that of normal cartilage. Histological analysis of the repaired defects showed that the hydrogel implant filled the defect with no signs of inflammation as it was well anchored to the surrounding tissues, resulting in a newly formed articular surface. In the case of empty control defects, osseous tissue grew inside the defects and fibrous tissue formed on the articular surface of the defects. The repaired surface of the hydrogel implant was more compliant than normal articular cartilage throughout the 16 weeks following the operation, whereas the fibrous tissue that formed postoperatively over the empty defect was stiffer than normal articular cartilage after 5 weeks. This stiffness started to decrease 16 weeks after the operation, probably due to tissue degeneration. Thus, from the biomechanical and histological point of view, the hydrogel implant improved the articular surface repair.33307-1

Expression of Groucho/TLE proteins during pancreas development

<p>Abstract</p> <p>Background</p> <p>The full-length mammalian homologs of <it>groucho</it>, Tle1, 2, 3, and 4, act as transcriptional corepressors and are recruited by transcription factors containing an eh1 or WRPW/Y domain. Many transcription factors critical to pancreas development contain a Gro/TLE interaction domain and several have been shown to require Gro/TLE interactions for proper function during neuronal development. However, a detailed analysis of the expression patterns of the Gro/TLE proteins in pancreas development has not been performed. Moreover, little is known about the ability of Gro/TLE proteins to interact with transcription factors in the pancreas.</p> <p>Results</p> <p>We describe the expression of Gro/TLE family members, and of 34 different transcription factors that contain a Gro/TLE interaction motif, in the pancreas utilizing nine SAGE libraries created from the developing and adult pancreas, as well as the <it>GenePaint </it>database. Next, we show the dynamic expression of <it>Tle1</it>, <it>2</it>, <it>3</it>, <it>4, 5 </it>and <it>6 </it>during pancreas development by qRT-PCR. To further define the cell-type specificity of the expression of these proteins we use immunofluorescence to co-localize them with Pdx1 at embryonic day 12.5 (E12.5), Ngn3 at E14.5, Pdx1, Nkx2-2, Insulin, Glucagon, Pancreatic polypeptide and Somatostatin at E18.5, as well as Insulin and Glucagon in the adult. We then show that Tle2 can interact with Nkx2-2, Hes1, Arx, and Nkx6-1 which are all critical factors in pancreas development. Finally, we demonstrate that Tle2 modulates the repressive abilities of Arx in a β-cell line.</p> <p>Conclusion</p> <p>Although Tle1, 2, 3, and 4 show overlapping expression in pancreatic progenitors and in the adult islet, the expression of these factors is restricted to different cell types during endocrine cell maturation. Of note, Tle2 and Tle3 are co-expressed with Gro/TLE interaction domain containing transcription factors that are essential for endocrine pancreas development. We further demonstrate that Tle2 can interact with several of these factors and that Tle2 modulate Arx's repressive activity. Taken together our studies suggest that Gro/TLE proteins play a role in the repression of target genes during endocrine cell specification.</p

Causality estimates among brain cortical areas by Partial Directed Coherence: simulations and application to real data

The problem of the definition and evaluation of brain connectivity has become a central one in neuroscience during the latest years, as a way to understand the organization and interaction of cortical areas during the execution of cognitive or motor tasks. Among various methods established during the years, the Partial Directed Coherence (PDC) is a frequency-domain approach to this problem, based on a multivariate autoregressive modeling of time series and on the concept of Granger causality. In this paper we propose the use of the PDC method on cortical signals estimated from high resolution EEG recordings, a non invasive method which exhibits a higher spatial resolution than conventional cerebral electromagnetic measures. The principle contributions of this work are the results of a simulation study, testing the performances of PDC, and a statistical analysis (via the ANOVA, analysis of variance) of the influence of different levels of Signal to Noise Ratio and temporal length, as they have been systematically imposed on simulated signals. An application to high resolution EEG recordings during a foot movement is also presented

The stability of lidocaine and epinephrine solutions exposed to electric current and comparative administration rates of the two drugs into pig bladder wall.

Intravesical electromotive administration of local anesthetics is clinically successful but electrochemistry, cost and effectiveness limit the choice of drugs to diluted lidocaine HCl 4% mixed with epinephrine. These studies address the stability of lidocaine and epinephrine both over time and when exposed to electric current, i.e. transport rates with passive diffusion and electromotive administration. The drug mixture used was 50 ml lidocaine 4%, 50 ml H2O and 1 ml epinephrine 1/1000. For stability, the solution was placed either in bowls for 7 days or in a two chamber cell with the donor compartment (drugs) separated from the receptor compartment (NaCl solution) by a viable pig bladder wall. This was subjected to 30 mA for 45 min. Stability was measured with mass spectrometry. The cell was also used to determine transport rates with passive diffusion and currents of 20 mA and 30 mA, over 20, 30 and 45 min. Drug measurements in both compartments and bladder were made with HPLC. Lidocaine remained stable throughout the 7 days, epinephrine on day 1 only and both drugs were stable with 30 mA for 45 min. Comparing 20 mA and 30 mA with passive diffusion, there were significant differences in 6/6 donor compartment lidocaine levels, 4/6 receptor compartment levels and 6/6 bladder tissue levels and also in 6/6 epinephrine donor levels and 6/6 tissue levels. The combination lidocaine and epinephrine remains stable for 1 day and when exposed to 30 mA for 45 min. Electric current accelerates the transport of lidocaine and epinephrine

Identification of transcripts with enriched expression in the developing and adult pancreas

The expression profile of different developmental stages of the murine pancreas and predictions of transcription factor interactions, provides a framework for pancreas regulatory networks and development

Fermented dairy products based on ovine cheese whey

This work presents an alternative solution for ovine whey components recovery in medium/small cheese plants that predominate in the rural areas of Southern European countries, which are specialized in the production of protected designation of origin (PDO) cheeses. These plants lack the capacity to concentrate and dry whey, and although a significant amount of this by-product is used in the manufacture of whey cheeses, in several cases it is used as animal feed or simply discarded. As an alternative to these practices, we propose the production of liquid whey protein concentrates (LWPC) by means of ultrafiltration (UF) followed by thermal denaturation and homogenization and their utilization in the production of fermented products based on kefir grains and/or commercial probiotic bacteria. Two types of fermented products were prepared: one in a liquid form (low protein and fat contents) and other in a gel form (high protein and fat contents). The microbiological, physicochemical (gross composition, pH, titratable acidity) and rheological properties of such products were assessed and compared during fermentation and at the 7th, 14th and 21st days of refrigerated storage. The fermented products presented adequate amounts of lactococci, lactobacilli (>7 Log10 CFUmL-1) and yeasts (>6 Log10 CFUmL-1). The rheological properties of liquid products were stable during the 21 days of refrigerated storage. However, gel type products showed variations in viscosity after 14 days, in the cases in which kefir grains were present. Although further work is needed in order to optimize the formulations regarding to the improvement of their sensory properties, it was concluded that this approach allows for the production of innovative fermented dairy products.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Small-angle X-ray scattering of heat-treated flame-fused silica glass from amorphous and crystalline powders

High-quality as-fused silica glass, heat treated at 1523 K and prepared by the flame-fusion process using natural crystalline quartz and high-purity amorphous silica glass powders, was investigated by small-angle X-ray scattering (SAXS). The X-ray scattering intensity amplitude from the amorphous structure after heat treatment was analysed in terms of viscosity, density and metallic impurity content. It is shown that SAXS scattering of the amorphous sample is sensitive to the structural change induced by annealing.30691892

Carbenic nitrile imines: Properties and reactivity

Structures and properties of nitrile imines were investigated computationally at B3LYP and CCSD(T) levels. Whereas NBO analysis at the B3LYP DFT level invariably predicts a propargylic electronic structure, CCSD(T) calculations permit a clear distinction between propargylic, allenic, and carbenic structures. Nitrile imines with strong IR absorptions above ca. 2150 cm-1 have propargylic structures with a CN triple bond (RCNNSiMe 3 and R2BCNNBR2), and those with IR absorptions below ca. 2150 cm-1 are allenic (HCNNH, PhCNNH, and HCNNPh). Nitrile imines lacking significant cumulenic IR absorptions at 1900-2200 cm -1 are carbenic (R-(C:)-N=N-R′). Electronegative but lone pair-donating groups NR2, OR, and F stabilize the carbenic form of nitrile imines in the same way they stabilize "normal" singlet carbenes, including N-heterocyclic carbenes. NBO analyses at the CCSD(T) level confirm the classification into propargylic, allenic, and carbenic reactivity types. Carbenic nitrile imines are predicted to form azoketenes 21 with CO, to form [2+2] and [2+4] cycloadducts and borane adducts, and to cyclize to 1H-diazirenes of the type 24 in mildly exothermic reactions with activation energies in the range 29-38 kcal/mol. Such reactions will be readily accessible photochemically and thermally, e.g., under the conditions of matrix photolysis and flash vacuum thermolysis

Pulmonary Resection for Metastasis of Hepatocellular Carcinoma Recurring After Liver Transplant : An Italian Multicenter Experience

Background and aim: Liver transplantation (LT) is a validated treatment for hepatocellular carcinoma (HCC). HCC recurrence occurred between 8 and 20% of patients and lung is the most frequent site. Pulmonary metastases resection (PMR) prolongs survival, however in LT-setting the impact on survival is unclear. To give new lights on this issue, we report the experience of three Italian LT Centers. Methods: All consecutive HCC transplanted patients in three Italian LT Centers, who developed pulmonary metastasis from HCC (PM-HCC), as first metastasis, from 2008 to 2018, were included whenever treated with PMR. Results: Twenty-five patients were enrolled (median age 58 yrs, 84% male, 3% cirrhotics). HCC recurred after 34 months (9\u2013306) since LT and PMR was performed after 2.4 months (0\u201343.1). A total of 28 PMR (19 single resections; 9 multiple resections; 16 right; 2 left) have been performed on 24 patients while in one case percutaneous microwave ablation (MWA) was preferred. Four patients have been re-operated due to pulmonary HCC-recurrence after surgery. The majority of surgical resection type was wedge resection (26, 89%). Surgical access was: video-assisted thoracic surgery (VATS) in 17 cases (59%); thoracotomy in 11 (38%); MWA in 1 (3%). The 48% of nodule was in right lower lobe. Perioperative in-hospital mortality and 30 days mortality were nil; median surgical time 90 min (50\u2013365); median post-operative overall stay 5 days (2\u201311). Post-operative ICU treatment was necessary in 1 case (3%) for 3 days; blood transfusions in 2 cases (7%). Overall, 5 complications (2 bleeding; 1 AKI; 1 major cardiac; 1 wound dehiscence) occurred, with an overall complications rate of 23%. Eight (32%) patients died during a follow-up after HCC recurrence of 32 months (7\u2013213): 7 for HCC progression, 1 for severe liver failure due to chronic rejection. The 1 and 5 year cumulative probability of OS from recurrence were 100 and 43% (95%CI 12\u201374), respectively, with a median OS of 51 months (95%CI 24\u201378). Conclusion: Selected patients with isolated pulmonary HCC-recurrence after LT and with preserved hepatic function showed that a pulmonary metastasectomy could be efficacious in managing a PM-HCC and could give an opportunity for long-term survival