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1.
ACS Appl Mater Interfaces ; 9(1): 266-278, 2017 01 11.
Article in English | MEDLINE | ID: mdl-28009160

ABSTRACT

In this work, we report the synthesis of functional biocompatible piezoelectric (1 - x)Ba(Ti0.8Zr0.2)TiO3-x(Ba0.7Ca0.3)TiO3, x = 0.45 (BCZT45), thin films with high piezoelectric properties. Pulsed-laser-based techniques, classical pulsed-laser deposition and matrix-assisted pulsed-laser evaporation, were used to synthesize the BCZT45 thin films. The second technique was employed in order to ensure growth on polymer flexible Kapton substrates. The BCZT45 thin films grown by both techniques show similar structural properties and high piezoelectric coefficient coupling between the mechanical loading and electrical potential. While it has long been shown that the electrical potential favors biological processes like osteogenesis, the assessment of cell adhesion and osteogenic differentiation onto BCZT materials has not yet been demonstrated. We prove here for the first time that BCZT 45 coatings on Kapton polymer substrates provide optimal support for osteogenic differentiation of mesenchymal stem cells in the bone marrow.


Subject(s)
Biocompatible Materials/chemistry , Cell Adhesion , Lasers , Osteogenesis , Polymers
2.
Biomater Sci ; 4(11): 1562-1573, 2016 Oct 18.
Article in English | MEDLINE | ID: mdl-27709146

ABSTRACT

The typical foreign body response (FBR) to synthetic implants is characterized by local inflammation and tissue fibrosis. Silicone implants have been associated with the development of adverse capsular contraction (ACC); a form of excessive FBR to the material that often requires the replacement of the implant. It has been shown that surface roughening of silicone can reduce the prevalence of ACC, but the mechanisms remain poorly understood. Macrophages are key cells in FBR. They exert their control mainly by polarizing into pro-inflammatory (M1) or pro-healing (M2) cells. It is postulated that surface topography can reduce M1 polarization by limiting cell spreading and cytoskeleton organization. To test this hypothesis, we used KrF Excimer laser ablation with half-tone masks to produce convex and concave topographies with controlled surface dimensional parameters. Cells in convex and concave topographies were compared to cells in planar surfaces, with or without chemical polarization. We show that chemical polarization induced specific changes in the cell shape on planar substrates. Macrophage shape and size was different in concave and convex surfaces, but no correlation was found with the cell polarization state. The results highlight that chemical polarization of macrophages is associated with changes in the cell shape; however, topography-induced changes in macrophage shape could not be linked with a shift in macrophage polarization. Thus, the sole manipulation of cell shape does not seem to be the mechanism by which macrophage function could be controlled.


Subject(s)
Cell Shape/physiology , Macrophages/cytology , Silicones/chemistry , Cell Polarity , Humans , Inflammation , Macrophages/chemistry , Macrophages/immunology , Prostheses and Implants , Wound Healing
3.
J Med Life ; 6(3): 240-3, 2013 Sep 15.
Article in English | MEDLINE | ID: mdl-24146681

ABSTRACT

Organ failure can be defined as a relevant concept of functional-anatomical condition of body structural change. Anatomical, functional disorders of the body are the expression of structural remodeling. The process is complex, including the first functional cell mass reduction (in particular, apoptosis and necrosis), and on the other hand the development of fibrosis process with a starting point at the extracellular matrix. Both mechanisms that take place are caused by etiological factors, enhanced, favoring the developer cytokines mediated by inflammatory processes such as premature death and functional constituent cells of the body; secondly the inflammation leads to fibrosis. The article review is a summary of the knowledge that exist at the level of the anatomical organ remodeling.


Subject(s)
Multiple Organ Failure/pathology , Multiple Organ Failure/physiopathology , Oxidative Stress , Animals , Apoptosis , Extracellular Matrix/metabolism , Fibrosis/pathology , Fibrosis/physiopathology , Humans , Reactive Oxygen Species/metabolism
4.
J Evol Biol ; 26(10): 2095-106, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23909947

ABSTRACT

Molecular studies of natural populations are often designed to detect and categorize hidden layers of cryptic diversity, and an emerging pattern suggests that cryptic species are more common and more widely distributed than previously thought. However, these studies are often decoupled from ecological and behavioural studies of species divergence. Thus, the mechanisms by which the cryptic diversity is distributed and maintained across large spatial scales are often unknown. In 1988, it was discovered that the common Eurasian Wood White butterfly consisted of two species (Leptidea sinapis and Leptidea reali), and the pair became an emerging model for the study of speciation and chromosomal evolution. In 2011, the existence of a third cryptic species (Leptidea juvernica) was proposed. This unexpected discovery raises questions about the mechanisms preventing gene flow and about the potential existence of additional species hidden in the complex. Here, we compare patterns of genetic divergence across western Eurasia in an extensive data set of mitochondrial and nuclear DNA sequences with behavioural data on inter- and intraspecific reproductive isolation in courtship experiments. We show that three species exist in accordance with both the phylogenetic and biological species concepts and that additional hidden diversity is unlikely to occur in Europe. The Leptidea species are now the best studied cryptic complex of butterflies in Europe and a promising model system for understanding the formation of cryptic species and the roles of local processes, colonization patterns and heterospecific interactions for ecological and evolutionary divergence.


Subject(s)
Butterflies/genetics , Genetic Variation , Reproductive Isolation , Animals , Butterflies/physiology , DNA/chemistry , DNA, Mitochondrial/chemistry , Gene Flow , Genetic Markers , Geography , Phylogeny , Sequence Analysis, DNA , Sexual Behavior, Animal
5.
Biomed Microdevices ; 10(5): 719-25, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18553133

ABSTRACT

The direct-writing technique laser-induced forward transfer has been employed for the micro-array printing of liquid solutions of the enzyme horseradish peroxidase and the protein Titin on nitrocellulose solid surfaces. The effect of two UV laser pulse lengths, femtosecond and nanosecond has been studied in relation with maintaining the activity of the transferred biomolecules. The quantification of the active biomolecules after transfer has been carried out using Bradford assay, quantitative colorimetric enzymatic assay and fluorescence techniques. Spectrophotometric measurements of the HRP and the Titin activity as well as chromatogenic and fluorescence assay studies have revealed a connection between the properties of the deposited, biologically active biomolecules, the experimental conditions and the target composition. The bioassays have shown that up to 78% of the biomolecules remained active after femtosecond laser transfer, while this value reduced to 54% after nanosecond laser transfer. The addition of glycerol in a percentage up to 70% in the solution to be transferred has contributed to the stabilization of the micro-array patterns and the increase of their resolution.


Subject(s)
Horseradish Peroxidase/analysis , Lasers , Microchemistry/methods , Muscle Proteins/analysis , Protein Array Analysis/methods , Protein Kinases/analysis , Biological Assay , Connectin , Horseradish Peroxidase/metabolism , Muscle Proteins/metabolism , Protein Kinases/metabolism , Spectrophotometry , Surface Properties
6.
Rev Med Chir Soc Med Nat Iasi ; 111(1): 135-43, 2007.
Article in Romanian | MEDLINE | ID: mdl-17595859

ABSTRACT

Pain is a common occurrence for the hospitalized elderly, and may often be under recognized and inadequately managed. Insufficient pain management can lead to the sequelae of emotional distress and depression, delirium, anxiety, sleep disturbances, and physical disabilities, as well as increased health care costs. Effective pain management of the older adult begins with pain assessment using the proper tools. Morphine is the analgesic of choice for the older adult, and is appropriate for the postoperative period. It is important to maintain a therapeutic serum level of opioids to prevent inadequate management of the acute pain. Side effects of opioids include hypotension, nausea, mood disturbances, ileus, histamine production, and respiratory depression. The adage for pain treatment in the elderly is "start low and go slow". Paracetamol is commonly prescribed and may be the drug of choice for mild to moderate postoperative pain. Older adults may enjoy the benefits of Patient-Controlled Analgesia and Patient Controlled Epidural Analgesia in the postoperative period; however, thorough and ongoing teaching must occur to ensure understanding and compliance with the therapy. Treating post-procedure pain in the elderly patient requires an understanding of the normal changes associated with aging and the impact on medications, and multimodal analgesia can be the best approach.


Subject(s)
Acetaminophen/therapeutic use , Aging , Analgesics, Non-Narcotic/therapeutic use , Analgesics, Opioid/therapeutic use , Morphine/therapeutic use , Pain, Postoperative/drug therapy , Aged , Analgesia, Patient-Controlled , Drug Therapy, Combination , Humans , Pain Measurement , Severity of Illness Index
7.
Chirurgia (Bucur) ; 99(2): 145-50, 2004.
Article in Hungarian | MEDLINE | ID: mdl-15279445

ABSTRACT

We present the cases of three brothers (a woman and two men) with recurrent attacks of necrotic acute pancreatitis that were treated in our clinic. Two of them have diabetes mellitus controlled through insulin treatment. All patients have presented the first episode of acute pancreatitis around age of 35. We have observed a high level of serum triglyceride at admission, without evidence of lipid disorder. In addition we couldn't identify other causes of these episodes of acute pancreatitis (biliary stones, alcohol, trauma, drugs, lipid disorders). During the last year two members of this family presented recurrent attacks of abdominal pain without any biochemical or imaging signs of acute pancreatitis.


Subject(s)
Pancreatitis/genetics , Adult , Female , Humans , Male , Middle Aged , Pancreatitis/diagnosis , Pancreatitis/therapy , Pedigree , Treatment Outcome
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