Scaffold morphology plays a key role in the development of tissue engineering constructs. The control of pore size, shape and interconnection is needed to achieve adequate nutrient transport and cell ...ingrowth. Several techniques are available for scaffold manufacturing, but none allows easy control of morphology and is, at the same time, applicable to a wide variety of materials. To investigate the possibility of processing a wide range polymers by solvent casting/particulate leaching with accurate control of scaffold morphology, three different porogens (gelatin microspheres, paraffin microspheres and sodium chloride crystals) were used to fabricate scaffolds from commonly employed biodegradable polymers. The outcome of processing was evaluated in terms of scaffold morphology and structure/properties relationships. Highly porous scaffolds were obtained with all porogens and well defined spherical pores resulted from microspheres leaching. Furthermore, scaffolds with spherical pores showed better mechanical performance and lower flow resistance. Cytocompatibility tests performed showed no evidence of processing residuals released from the scaffolds. Solvent casting/microspheres leaching, particularly gelatin microspheres leaching, can be used to process a large number of polymers and enables to tailor scaffold pore size, shape and interconnection, thus providing a powerful tool for material selection and optimization of scaffold morphology.
BACKGROUND To estimate the incidence of aneuploidy in relation to patients' characteristics, the type of hormonal stimulation and their response to induction of multiple follicular growth, 4163 first ...polar bodies (PB1s) were analyzed. METHODS Five hundred and forty four infertile couples underwent 706 assisted conception cycles (640 with poor prognosis indications and 66 controls) in which chromosomal analysis of PB1 for the chromosomes 13, 15, 16, 18, 21 and 22 was performed. Results were evaluated in a multivariate analysis. RESULTS The proportion of normal oocytes was directly correlated (P < 0.01) with (i) the number of mature oocytes and (ii) the establishment of a clinical pregnancy; and inversely correlated (P < 0.01) with (i) female age, (ii) causes of female infertility (endometriosis, abortions, ovulatory factor), (iii) poor prognosis indications (female age, number of previous cycles, multiple poor prognosis indications), (iv) number of FSH units per oocyte and (v) number of FSH units per metaphase II oocyte. There was a weak significance of frequency (P < 0.05) between type of abnormality (originated by chromatid predivision, chromosome non-disjunction or combined mechanisms in the same oocyte) and groups of the studied variables, rather than to a specific abnormality or a specific chromosome. CONCLUSIONS The type of infertility had a significant effect on errors derived from the first meiotic division, whose incidence was significantly higher in the presence of endometriosis or of an ovulatory factor, and in women that experienced repeated abortions. Each aneuploidy event was found to be dependent not on a specific variable, but on groups of variables. In addition, the tendency of chromosomal abnormalities to occur simultaneously implies that the deriving aneuploidies can be of any type.
The paper focuses on the educational experience produced during the International Workshop, organized by the IUAV University of Venice and dedicated to both the understanding and conservation of the ...maison Stein-de-Monzie “Les Terrasses”, an emblematic work of Le Corbusier’s early career period. The villa, located in Garches (Vaucresson), was designed and built between 1926 and 1928, the exact same years when Le Corbusier was elaborating the “Five Points of Architecture” (1927): the building is the first complete application of these principles, while it represents an evolution of the maison Dom-Ino’s structural scheme. Nowadays, both the interior spaces and the external surfaces of the maison Stein-de-Monzie show profound changes caused by problematic events leading to the present-day appearance of the building, in many cases misrepresenting the original design goals. The building’s integrated instrumental survey (laser scanning, photogrammetry, topography) allowed to document and understand the history of the villa beyond the mere and well known project phase, contributing to the definition of the actual construction characteristics and to ascertain both the material consistency and the state of conservation. The knowledge acquisition process – supported by survey data – constitutes a prerequisite to outline the design of new solutions, which could effectively express the cultural choices connected to the conservation of the Twentieth-Century built heritage.
Background: The colonic epithelium maintains a life long reciprocally beneficial interaction with the colonic microbiota. Disruption is associated with mucosal injury. Aims: We hypothesised that ...probiotics may limit epithelial damage induced by enteroinvasive pathogens, and promote restitution. Methods: Human intestinal epithelial cell lines (HT29/cl.19A and Caco-2) were exposed to enteroinvasive Escherichia coli (EIEC 029:NM), and/or probiotics (Streptococcus thermophilus (ST), ATCC19258, and Lactobacillus acidophilus (LA), ATCC4356). Infected cells and controls were assessed for transepithelial resistance, chloride secretory responses, alterations in cytoskeletal and tight junctional proteins, and responses to epidermal growth factor (EGF) stimulation. Results: Exposure of cell monolayers to live ST/LA, but not to heat inactivated ST/LA, significantly limited adhesion, invasion, and physiological dysfunction induced by EIEC. Antibiotic killed ST/LA reduced adhesion somewhat but were less effective in limiting the consequences of EIEC invasion of cell monolayers. Furthermore, live ST/LA alone increased transepithelial resistance, contrasting markedly with the fall in resistance evoked by EIEC infection, which could also be blocked by live ST/LA. The effect of ST/LA on resistance was accompanied by maintenance (actin, ZO-1) or enhancement (actinin, occludin) of cytoskeletal and tight junctional protein phosphorylation. ST/LA had no effect on chloride secretion by themselves but reversed the increase in basal secretion evoked by EIEC. EIEC also reduced the ability of EGF to activate its receptor, which was reversed by ST/LA. Conclusions: Live ST/LA interact with intestinal epithelial cells to protect them from the deleterious effect of EIEC via mechanisms that include, but are not limited to, interference with pathogen adhesion and invasion. Probiotics likely also enhance the barrier function of naïve epithelial cells not exposed to any pathogen.
Endometriosis is a gynecological disease, which involves the growth of endometrial tissue outside the uterine cavity, commonly in the pelvic region. The etiology of the disease is unclear, but ...multiple factors may contribute to its pathogenesis. Environmental organochlorinated pollutants, particularly dioxins and polychlorinated biphenyls (PCBs), are thought to play a role in the development of this disease; however, the results of clinical trials are discordant, and it is not clear how the effect of exposure to these compounds is linked to endometriosis. Their effects on cytokines, immune system, hormones, and growth factors are thought to increase the risk of endometriosis. The purpose of this review is to provide an overview of epidemiological studies, which have evaluated the relationship between endometriosis and exposure to persistent organochlorinated pollutants.
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