9 results on '"Constantinos C. Frangos"'
Search Results
2. Rapid magnetic cell delivery for large tubular bioengineered constructs
- Author
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Mark F. Lythgoe, S. Husain, Quentin A. Pankhurst, Daniel Ortega, Jordi Gonzalez-Molina, Richard M. Day, Johannes Riegler, Paul Southern, Y. Angelopoulos, and Constantinos C. Frangos
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Materials science ,Uniform distribution (continuous) ,Cell Survival ,Cell Transplantation ,Cell Culture Techniques ,Biomedical Engineering ,Biophysics ,Bioengineering ,Nanotechnology ,Ferric Compounds ,Biochemistry ,Cell Line ,Biomaterials ,Magnetics ,Mice ,Microscopy, Electron, Transmission ,Tissue engineering ,Microscopy ,Animals ,Cylinder ,Magnetite Nanoparticles ,Process (anatomy) ,Research Articles ,Analysis of Variance ,Tissue Engineering ,Halbach array ,Cell culture ,Seeding ,Biotechnology ,Biomedical engineering - Abstract
Delivery of cells into tubular tissue constructs with large diameters poses significant spatial and temporal challenges. This study describes preliminary findings for a novel process for rapid and uniform seeding of cells onto the luminal surface of large tubular constructs. Fibroblasts, tagged with superparamagnetic iron oxide nanoparticles (SPION), were directed onto the luminal surface of tubular constructs by a magnetic field generated by a k4-type Halbach cylinder device. The spatial distribution of attached cells, as measured by the mean number of cells, was compared with a conventional, dynamic, rotational cell-delivery technique. Cell loading onto the constructs was measured by microscopy and magnetic resonance imaging. The different seeding techniques employed had a significant effect on the spatial distribution of the cells ( p < 0.0001). The number of attached cells at defined positions within the same construct was significantly different for the dynamic rotation technique ( p < 0.05). In contrast, no significant differences in the number of cells attached to the luminal surface were found between the defined positions on the construct loaded with the Halbach cylinder. The technique described overcomes limitations associated with existing cell-delivery techniques and is amenable to a variety of tubular organs where rapid loading and uniform distribution of cells for therapeutic applications are required.
- Published
- 2012
- Full Text
- View/download PDF
3. Higoumenakis’ sign in the diagnosis of congenital syphilis in anthropological specimens
- Author
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Christos C. Frangos, Giagkos Lavranos, and Constantinos C. Frangos
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medicine.medical_specialty ,Pathology ,Treponema ,biology ,business.industry ,Syphilis, Congenital ,General Medicine ,Disease ,medicine.disease ,Dna amplification ,biology.organism_classification ,Clavicle ,Sensitivity and Specificity ,Dermatology ,medicine.anatomical_structure ,Congenital syphilis ,Anthropology ,medicine ,Humans ,Syphilis ,In patient ,business ,Paleopathology - Abstract
Higoumenakis' sign (HS) is a diagnostic criterion referring to the enlargement of the sternal end of the (right) clavicle, frequently observed in patients with late congenital syphilis. Although indexed for several years in clinical medicine textbooks, it has not been extensively applied for the diagnosis of congenital syphilis among anthropological specimens. This is highly significant, since the other major palaeopathology findings refer almost exclusively to the skull and diagnosis thus becomes difficult if only peripheral skeletal remains are available for evaluation. The potential effectiveness of the proposed use of HS as a marker of syphilis in anthropology appears adequate, since descriptions very similar to that of HS have been reported for certain findings, although no attempt has been made to correlate them with the presence of the disease. Higoumenakis himself originally observed this sign in 86% of his patients with congenital syphilis, and this report was subsequently verified by other independent researchers. His attempt to explain the pathophysiology of the sign and its localisation, on the basis of anatomical, biological, and mechanical reasons, however, has been questioned. On the other hand, the application of the remaining markers of congenital syphilis is also problematic, due to sensitivity and/or specificity limitations, and other signs may not be detected due to inability to retain soft tissue samples in anthropological populations and a lack of reliable techniques for treponematous DNA amplification in such old samples. Thus, the fact that the onset of any of the signs of syphilis is not a constant finding justifies the authors' suggestion that HS should be checked for in any available anthropological specimen, because it is highly indicative of possible infection by Treponema pallidum.
- Published
- 2011
- Full Text
- View/download PDF
4. George Higoumenakis (1895-1983): Greek dermatologist
- Author
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Constantinos C. Frangos and Christos C. Frangos
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medicine.medical_specialty ,Eponyms ,Parliament ,media_common.quotation_subject ,Leishmaniasis, Cutaneous ,Medicine (miscellaneous) ,Dermatology ,Politics ,History and Philosophy of Science ,Hygiene ,medicine ,Humans ,Psoriasis ,In patient ,media_common ,Greece ,business.industry ,Syphilis, Congenital ,Medical school ,History, 20th Century ,medicine.disease ,Clavicle ,Congenital syphilis ,George (robot) ,Syphilis ,business - Abstract
This paper describes the Higoumenakis sign, enlargement of the sternal end of the clavicle in patients with late congenital syphilis and the dermatologist after whom it is named. Several professors and doctors from the Medical School of the University of Athens opposed his actions especially at the University in Greece. His persistence led him to productive scientific activity in syphilis, leishmaniasis and psoriasis. He became a member of the Greek Parliament from 1964 to 1967 and eventually Minister of Hygiene - even though this may have been an imprudent political choice, due to the unstable sociopolitical status of that period. He died on 27 December 1983 at the age of 88.
- Published
- 2009
- Full Text
- View/download PDF
5. Spatial and temporal evaluation of cell attachment to printed polycaprolactone microfibres
- Author
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Richard M. Day, Zeeshan Ahmad, Constantinos C. Frangos, Laurent Bozec, Manoochehr Rasekh, and Mohan Edirisinghe
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Topography ,business.product_category ,Materials science ,Time Factors ,Polyesters ,Cell ,Biomedical Engineering ,Cell Culture Techniques ,Biocompatible Materials ,Surface finish ,Microscopy, Atomic Force ,Biochemistry ,Time-Lapse Imaging ,Time-lapse microscopy ,Biomaterials ,chemistry.chemical_compound ,Mice ,Computer Systems ,Microfiber ,Microscopy ,medicine ,Cell Adhesion ,Animals ,Molecular Biology ,Process (anatomy) ,Direct writing ,General Medicine ,Electrohydrodynamic ,Fibroblasts ,In vitro biocompatibility ,Solutions ,medicine.anatomical_structure ,chemistry ,Polycaprolactone ,Solvents ,Printing ,business ,Biotechnology ,Biomedical engineering - Abstract
Surface topography plays a crucial role in influencing cellular responses and has therefore been utilized in the development of numerous implantable devices. Whilst numerous studies have either investigated cell attachment or migration post-attachment, few have looked at the early-stages of this process temporally. The aim of this study was to evaluate the use of time-lapse microscopy to study the behaviour of fibroblasts cultured with polycaprolactone microfibres and to assess spatially and temporally the cell–structure interaction over a 24 h period. Ordered polymeric structures were printed (predetermined) onto glass substrates using an electrohydrodynamic direct write process to produce fine (3–5 lm wide) structures. Fibroblast attachment and migration were characterized as a function of distance perpendicular from structures ( 17.3, 34.6 and 51.9 lm). The use of time-lapse microscopy revealed a gradual decrease in cell attachment as the distance from the microfibres was increased. The technique also revealed that some cells were attaching and detaching from the microfibre multiple times. Our findings demonstrate that time-lapse microscopy is a useful technique for evaluating early-stage cell–biomaterial interaction that is capable of recording important events that might otherwise be overlooked.
- Published
- 2012
6. Problematic Internet Use among Greek university students: an ordinal logistic regression with risk factors of negative psychological beliefs, pornographic sites, and online games
- Author
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Christos C. Frangos, Constantinos C. Frangos, and Ioannis Sotiropoulos
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Adult ,Male ,Social Psychology ,Adolescent ,Universities ,Cross-sectional study ,media_common.quotation_subject ,education ,MEDLINE ,Sample (statistics) ,Young Adult ,Sex Factors ,Risk Factors ,Erotica ,Prevalence ,Humans ,Young adult ,Students ,Applied Psychology ,Negativism ,media_common ,Internet ,Greece ,business.industry ,Communication ,Addiction ,General Medicine ,Computer Science Applications ,Play and Playthings ,Human-Computer Interaction ,Behavior, Addictive ,Cross-Sectional Studies ,Logistic Models ,Attitude ,Unemployment ,Educational Status ,The Internet ,Female ,Ordered logit ,business ,Psychology ,Social psychology ,Demography - Abstract
The aim of this paper is to investigate the relationships between Problematic Internet Use (PIU) among university students in Greece and factors such as gender, age, family condition, academic performance in the last semester of their studies, enrollment in unemployment programs, amount of Internet use per week (in general and per application), additional personal habits or dependencies (number of coffees, alcoholic drinks drunk per day, taking substances, cigarettes smoked per day), and negative psychological beliefs. Data were gathered from 2,358 university students from across Greece. The prevalence of PIU was 34.7% in our sample, and PIU was significantly associated with gender, parental family status, grade of studies during the previous semester, staying or not with parents, enrollment of the student in an unemployment program, and whether the student paid a subscription to the Internet (p 0.0001). On average, problematic Internet users use MSN, forums, YouTube, pornographic sites, chat rooms, advertisement sites, Google, Yahoo!, their e-mail, ftp, games, and blogs more than non-problematic Internet users. PIU was also associated with other potential addictive personal habits of smoking, drinking alcohol or coffee, and taking drugs. Significant risk factors for PIU were being male, enrolment in unemployment programs, presence of negative beliefs, visiting pornographic sites, and playing online games. Thus PIU is prevalent among Greek university students and attention should be given to it by health officials.
- Published
- 2011
7. On a Broader Description of Alimentary Consumption Patterns: The Case of Greece (1957-2005)
- Author
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Christos C. Frangos, Vassilios P. Filios, Ioannis Sotiropoulos, and Constantinos C. Frangos
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Consumption (economics) ,Operations research ,Agriculture ,business.industry ,Regional science ,Natural (music) ,Dimension (data warehouse) ,Individual level ,business ,Mathematics ,Simple (philosophy) - Abstract
Understanding the formation and evolution of alimentary consumption patterns requires a broad and multidimensional approach. Foods originate either from plants and animals, representing the living processes, or agriculture and industry, representing the non-living processes, and in these forms they play their biological role. Additionally, the consumption of foods has multiple consequences (social, economic, health, etc.) on an individual level as well as on a wider collective level. In this essay we attempt to describe alimentary consumption patterns in Greece (1957-2005) from three different dimensions: a natural dimension (animal or plant origin), a technical one (agricultural or industrial origin) and finally, a biological one (nutritional properties). The description, which we will use as the foundation to create an interpretative theory, is done through charts and tables, based on numerical indicators that are deduced from simple illustrative functions. Tables used in the present paper are either simple or double-entry and we present spreading diagrams as well.
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- 2010
- Full Text
- View/download PDF
8. George Higoumenakis (1895-1983): Greek dermatologist
- Author
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Frangos, Constantinos C. Frangos, Christos C.
- Subjects
humanities - Abstract
This paper describes the Higoumenakis sign, enlargement of the sternal end of the clavicle in patients with late congenital syphilis and the dermatologist after whom it is named. Several professors and doctors from the Medical School of the University of Athens opposed his actions especially at the University in Greece. His persistence led him to productive scientific activity in syphilis, leishmaniasis and psoriasis. fie became a member of the Greek Parliament from 1964 to 1967 and eventually Minister of Hygiene - even though this may have been an imprudent political choice, due to the unstable socio-political status of that period. He died on 27 December 1983 at the age of 88.
- Published
- 2009
9. Correction on the prevalence data of inflammatory bowel disease in Puerto Rico
- Author
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Constantinos C. Frangos
- Subjects
Gerontology ,medicine.medical_specialty ,business.industry ,Internal medicine ,Gastroenterology ,Immunology and Allergy ,Medicine ,business ,medicine.disease ,Inflammatory bowel disease - Published
- 2007
- Full Text
- View/download PDF
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