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Aim: Evaluate efficacy/safety of oral l-ornithine-l-aspartate (LOLA) in controlling minimal hepatic encephalopathy (MHE)., Methods: Consecutive cirrhotic outpatients with MHE (defined by psychometric number connection tests A/B [NCT-A/B] and digit symbol substitution test [DSST] score of >2 standard deviations) were randomized to a 60-day oral LOLA (5 g t.i.d) or placebo group. Critical flicker frequency test (CFF), quantitative electroencephalogram (qEEG), arterial ammonia (NH3), Beck's anxiety-depression forms and liver disease quality of life (LD-QOL) were assessed. Patients were followed for 6 months after the end of the study to assess LOLA prophylactic role on overt hepatic encephalopathy (OHE)., Results: Sixty-four patients were included, 63 (98.4%) with MHE. In six of these patients, CFT was less than 39 Hz (9.52%); NH3 was increased in 32 (50.8%); 25% had abnormal qEEG. Age, sex, scholarship, Child-Pugh (CP), Model for End-Stage Liver Disease, NCT-A/B, DSST, CFF and NH3 were similar in both groups at the baseline. LOLA led to a significant improvement in NCT-B age-controlled z-score (3.4 ± 3.4 vs 1.5 ± 2.3, P = 0.01) and CFF (42.2 ± 5.8 vs 45.2 ± 5.8, P = 0.02), comparing the first and the last visit, but there were no differences between LOLA and placebo regarding the whole psychometric battery, CFF, LD-QOL and Beck's forms. No serious adverse effects occurred. Patients taking LOLA had less episodes of OHE at 6 months (5% vs 37.9%, P = 0.016), as they have significant improvement on liver function assessed by CP (P < 0.001)., Conclusion: A 60-day oral LOLA course was not better than placebo in treating MHE, but was useful in preventing further episodes of OHE., (© 2013 The Japan Society of Hepatology.)

The aim of our study was to investigate the osteoinductive potential of a titanium (Ti) surface with nanotopography, using mesenchymal stem cells (MSCs) and the mechanism involved in this phenomenon. Polished Ti discs were chemically treated with H2 SO4 /H2 O2 to yield nanotopography and rat MSCs were cultured under osteogenic and non-osteogenic conditions on both nanotopography and untreated polished (control) Ti surfaces. The nanotopography increased cell proliferation and alkaline phosphatase (Alp) activity and upregulated the gene expression of key bone markers of cells grown under both osteogenic and non-osteogenic conditions. Additionally, the gene expression of α1 and β1 integrins was higher in cells grown on Ti with nanotopography under non-osteogeneic condition compared with control Ti surface. The higher gene expression of bone markers and Alp activity induced by Ti with nanotopography was reduced by obtustatin, an α1β1 integrin inhibitor. These results indicate that α1β1 integrin signaling pathway determines the osteoinductive effect of nanotopography on MSCs. This finding highlights a novel mechanism involved in nanosurface-mediated MSCs fate and may contribute to the development of new surface modifications aiming to accelerate and/or enhance the process of osseointegration., (© 2013 Wiley Periodicals, Inc.)

This study investigated the effect of pore size on osteoblastic phenotype development in cultures grown on porous titanium (Ti). Porous Ti discs with three different pore sizes, 312 μm (Ti 312), 130 μm (Ti 130) and 62 μm (Ti 62) were fabricated using a powder metallurgy process. Osteoblastic cells obtained from human alveolar bone were cultured on porous Ti samples for periods of up to 14 days. Cell proliferation was affected by pore size at day 3 (p=0.0010), day 7 (p=0.0005) and day 10 (p=0.0090) in the following way: Ti 62

The aim of this study was to characterize the physicochemical properties of bacterial cellulose (BC) membranes functionalized with osteogenic growth peptide (OGP) and its C-terminal pentapeptide OGP[10-14], and to evaluate in vitro osteoinductive potential in early osteogenesis, besides, to evaluate cytotoxic, genotoxic and/or mutagenic effects. Peptide incorporation into the BC membranes did not change the morphology of BC nanofibers and BC crystallinity pattern. The characterization was complemented by Raman scattering, swelling ratio and mechanical tests. In vitro assays demonstrated no cytotoxic, genotoxic or mutagenic effects for any of the studied BC membranes. Culture with osteogenic cells revealed no difference in cell morphology among all the membranes tested. Cell viability/proliferation, total protein content, alkaline phosphatase activity and mineralization assays indicated that BC-OGP membranes enabled the highest development of the osteoblastic phenotype in vitro. In conclusion, the negative results of cytotoxicity, genotoxicity and mutagenicity indicated that all the membranes can be employed for medical supplies, mainly in bone tissue engineering/regeneration, due to their osteoinductive properties.

The present study evaluated the progression of osteogenic cell cultures exposed to a novel calcium aluminate cement (CAC+) in comparison with the gold standard mineral trioxide aggregate (MTA). Cells were enzimatically isolated from newborn rat calvarial bone, plated on glass coverslips containing either CAC+ or a control MTA samples in the center, and grown under standard osteogenic conditions. Over the 10-day culture period, roundening of sample edges was clearly noticed only for MTA group. Although both cements supported osteogenic cell adhesion, spreading, and proliferation, CAC+-exposed cultures showed significantly higher values in terms of total cell number at days 3 and 7, and total protein content and alkaline phosphatase activity at day 10. The present in vitro results indicate that the exposure to CAC+ supports a higher differentiation of osteogenic cells compared with the ones exposed to MTA. Further experimental studies should consider CAC+ as a potential alternative to MTA when the repair of mineralized tissues is one of the desired outcomes in endodontic therapy.

This study investigated the response of human alveolar bone-derived cells to a novel poly(vinylidene fluoride-trifluoroethylene)/barium titanate (P(VDF-TrFE)/BT) membrane. Osteoblastic cells were cultured in osteogenic conditions either on P(VDF-TrFE)/BT or polytetrafluoroethylene (PTFE) for up to 14 days. At 7 and 14 days, the mRNA expression of Runt-related transcription factor 2 (RUNX2), Type I collagen (COL I), Osteopontin (OPN), Alkaline phosphatase (ALP), Bone sialoprotein (BSP), and Osteocalcin (OC), key markers of the osteoblastic phenotype, and of Bcl2-associated X protein (Bax), B-cell CLL/lymphoma 2 (Bcl-2), and Survivin (SUR), associated with the control of the apoptotic cell death, was assayed by real-time PCR. In situ ALP activity was qualitatively evaluated by means of Fast red staining. Surface characterization was also qualitatively and quantitatively assayed in terms of topography, roughness, and wettability. Cells grown on P(VDF-TrFE)/BT exhibited a significantly higher mRNA expression for all markers compared to the ones on PTFE, except for Bcl-2, which was not detected for both groups. Additionally, Fast red staining was noticeably stronger in cultures on P(VDF-TrFE)/BT at 7 and 14 days. At micron- and submicron scale, SEM images and roughness analysis revealed that PTFE and P(VDF-TrFE)/BT exhibited a smooth topography and a similar roughness, respectively. PTFE membrane displayed higher contact angles compared with P(VDF-TrFE)/BT, as indicated by wettability assay. The novel P(VDF-TrFE)/BT membrane supports the acquisition of the osteoblastic phenotype in vitro, while up-regulating the expression of apoptotic markers. Further in vivo experiments should be carried out to confirm the capacity of P(VDF-TrFE)/BT membrane in promoting bone formation in guided bone regeneration.

The aim of this work was to evaluate the biocompatibility of poly(vinylidene fluoride-trifluoroethylene)/barium titanate (P(VDF-TrFE)/BT) membrane to be used in guided tissue regeneration (GTR). Fibroblasts from human periodontal ligament (hPDLF) and keratinocytes (SCC9) were plated on P(VDF-TrFE)/BT and polytetrafluorethylene membranes at a cell density of 20,000 cells well(-1) and cultured for up to 21 days. Cell morphology, adhesion and proliferation were evaluated in hPDLF and keratinocytes, while total protein content and alkaline phosphatase (ALP) activity were assayed only for hPDLF. Using a higher cell density, real-time polymerase chain reaction (PCR) was performed to assess the expression of typical genes of hPDLF, such as periostin, PDLs17, S100A4 and fibromodulin, and key phenotypic markers of keratinocytes, including involucrin, keratins 1, 10 and 14. Expression of the apoptotic genes bax, bcl-2 and survivin was evaluated for both cultures. hPDLF adhered and spread more on P(VDF-TrFE)/BT, whereas keratinocytes showed a round shape on both membranes. hPDLF adhesion was greater on P(VDF-TrFE)/BT at 2 and 4h, while keratinocyte adhesion was similar for both membranes. Whereas proliferation was significantly higher for hPDLF on P(VDF-TrFE)/BT at days 1 and 7, no signs of keratinocyte proliferation could be noticed for both membranes. Total protein content was greater on P(VDF-TrFE)/BT at 7, 14 and 21 days, and higher levels of ALP activity were observed on P(VDF-TrFE)/BT at 21 days. Real-time PCR revealed higher expression of phenotypic markers of hPDLF and keratinocytes as well as greater expression of apoptotic genes in cultures grown on P(VDF-TrFE)/BT. These results indicate that, by favoring hPDLF adhesion, spreading, proliferation and typical mRNA expression, P(VDF-TrFE)/BT membrane should be considered an advantageous alternative for GTR., (Copyright 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

The aim of this study was to investigate the effects of low-level laser therapy (LLLT) by using gallium aluminum arsenide (GaAlAs) diode laser on human osteoblastic cells grown on titanium (Ti). Osteoblastic cells were obtained by enzymatic digestion of human alveolar bone and cultured on Ti discs for up to 17 days. Cells were exposed to LLLT at 3 J/cm2 (wavelength of 780 nm) at days 3 and 7 and non-irradiated cultures were used as control. LLLT treatment did not influence culture growth, ALP activity, and mineralized matrix formation. Analysis of cultures by epifluorescence microscopy revealed an area without cells in LLLT treated cultures, which was repopulated latter with proliferative and less differentiated cells. Gene expression of ALP, OC, BSP, and BMP-7 was higher in LLLT treated cultures, while Runx2, OPN, and OPG were lower. These results indicate that LLLT modulates cell responses in a complex way stimulating osteoblastic differentiation, which suggests possible benefits on implant osseointegration despite a transient deleterious effect immediately after laser irradiation.

One of the strategies to improve the mechanical performance of bioactive glasses for load-bearing implant devices has been the development of glass-ceramic materials. The present study aimed to evaluate the effect of a highly bioactive, fully-crystallized glass-ceramic (Biosilicate) of the system P(2)O(5)-Na(2)O-CaO-SiO(2) on various key parameters of in vitro osteogenesis. Surface characterization was carried out by scanning electron microscopy and Fourier transform infrared spectroscopy. Osteogenic cells were obtained by enzymatic digestion of newborn rat calvarial bone and by growing on Biosilicate discs and on control bioactive glass surfaces (Biosilicate) parent glass and Bioglass(R) 45S5) for periods of up to 17 days. All materials developed an apatite layer in simulated body fluid for 24h. Additionally, as early as 12 h under culture conditions and in the absence of cells, all surfaces developed a layer of silica-gel that was gradually covered by amorphous calcium phosphate deposits, which remained amorphous up to 72 h. During the proliferative phase of osteogenic cultures, the majority of cells exhibited disassembly of the actin cytoskeleton, whereas reassembly of actin stress fibers took place only in areas of cell multilayering by day 5. Although no significant differences were detected in terms of total protein content and alkaline phosphatase activity at days 11 and 17, Biosilicate supported significantly larger areas of calcified matrix at day 17. The results indicate that full crystallization of bioactive glasses in a range of compositions of the system P(2)O(5)-Na(2)O-CaO-SiO(2) may promote enhancement of in vitro bone-like tissue formation in an osteogenic cell culture system.

Glioblastomas are the most common type of brain tumors; astrocytic in their origin, they are anaplastic tumors, and are located mainly in the cerebral hemispheres. Primary growth in the conus medullaris is very rare, and the assessment and prognosis of this kind of tumor are distinct and unique. We present here the case of a 39 years-old man with an intramedullary tumor of the spinal cord, with an histo pathological diagnosis of glioblastoma, along with some therapeutic considerations.

Unlabelled: We report and discuss the case of a 55-year old man who presented a history of stroke as well as chronic obstructive pulmonary disease. When admitted into the emergency room, he was diagnosed with a vertebro-basilar syndrome. A brain MRI showed a hyperintense area in the lower right brainstem laterally within the medulla, which corresponds to the area of the pathways descending from the autonomic breathing control center. During hospitalization, the patient had several episodes of prolonged apnea, mainly when asleep, having often to be "reminded" to breath. A tracheostomy was then performed with the patient under mechanical ventilation. Treatment with medroxyprogesterone, fluoxetine and acetazolamide was also started. He was discharged after 64 days breathing environmental air with no apparent episodes of apnea. He returned to the emergency room in the following day with a clinical picture of aspiration bronchopneumonia, followed by septic shock and death., Conclusion: the Ondine's curse is one of the posterior stroke's presentation characterized by loss of automatic breathing and for the unpredictability of clinical evolution and prognosis. Such a syndrome has rarely been reported in adults and the diagnostic criteria are not consensual in the reviewed literature. Thus any diagnostic confirmation should be flexible. There are many therapeutic symptomatic options in such cases, ranging from pharmacologic approach, use of bilevel positive airway pressure and implantation of diaphragmatic pacemaker.