ABSTRACT
Microarray experiments are capable of determining the relative expression of tens of thousands of genes simultaneously, thus resulting in very large databases. The analysis of these databases and the extraction of biologically relevant knowledge from them are challenging tasks. The identification of potential cancer biomarker genes is one of the most important aims for microarray analysis and, as such, has been widely targeted in the literature. However, identifying a set of these genes consistently across different experiments, researches, microarray platforms, or cancer types is still an elusive endeavor. Besides the inherent difficulty of the large and nonconstant variability in these experiments and the incommensurability between different microarray technologies, there is the issue of the users having to adjust a series of parameters that significantly affect the outcome of the analyses and that do not have a biological or medical meaning. In this study, the identification of potential cancer biomarkers from microarray data is casted as a multiple criteria optimization (MCO) problem. The efficient solutions to this problem, found here through data envelopment analysis (DEA), are associated to genes that are proposed as potential cancer biomarkers. The method does not require any parameter adjustment by the user, and thus fosters repeatability. The approach also allows the analysis of different microarray experiments, microarray platforms, and cancer types simultaneously. The results include the analysis of three publicly available microarray databases related to cervix cancer. This study points to the feasibility of modeling the selection of potential cancer biomarkers from microarray data as an MCO problem and solve it using DEA. Using MCO entails a new optic to the identification of potential cancer biomarkers as it does not require the definition of a threshold value to establish significance for a particular gene and the selection of a normalization procedure to compare different experiments is no longer necessary.
Subject(s)
Biomarkers, Tumor/genetics , Oligonucleotide Array Sequence Analysis/methods , Uterine Cervical Neoplasms/genetics , Female , Gene Expression/genetics , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic , Humans , Systems Biology/methodsABSTRACT
Clinical evidence has shown that dental bridge (DB) misfit is more frequent than individual crown restoration misfit, and that it causes restorative failures. A comparative study of misfit profiles was performed for the most common clinical situations in mouth rehabilitation procedures with fixed restorations: gold-cast DB and porcelain metal alloy DB. Evidence from this study may lead dentists to consider the advantages and weaknesses of one structure type over the other. The results obtained showed two different profiles, with the porcelain metal alloy (PMA) DB being less predictable than the gold-cast DB. The posterior abutment restoration tends to come apart distally from the tooth structure and get closer to the mesial aspect, while keeping distal-medial separation with respect to the anterior abutment. The gold-cast DBs showed a separation pattern in which the distal end comes away from the molar and the medial end from the premolar, getting clearly closer to the faces next to the pontic: its distal aspect gets closer to the premolar and mesially to the molar The study has also shown that even though the adaptive patterns are different, is less in PMA than in gold alloys, the latter being used only in a small percentage of clinical indications in oral rehabilitation, mainly due to aesthetic demands and high costs. The impact of this research in clinical dentistry is that PMA DBs have shown worst marginal adaptation areas where clinically, there is lack of vision or inaccessibility for appropriate dental preparation.
Subject(s)
Dental Prosthesis , Gold Alloys , Humans , In Vitro Techniques , Metal Ceramic Alloys , Prosthesis FittingABSTRACT
Constrictive pericarditis is a rare but severely disabling consequence of the chronic inflammation of the pericardium, leading to an impaired filling of the ventricles and reduced ventricular function. Patients complain about fatigue, peripheral edema, breathlessness and abdominal swelling; signs and symptoms of right-sided heart failure. Besides history and physical examination, diagnostic studies aid in the diagnosis, including electrocardiogram, chest x-ray, echocardiogram, chest CT and/or MRI, and hemodynamic measurements. Medical management with diuretics and salt restriction is useful for symptomatic relief of fluid overload and peripheral edema, but patients ultimately become refractory. Although conservative treatment may alleviate the patient's symptoms, pericardiectomy remains the onlydefinitive treatment for the disease. An interesting and representative case of constrictive pericarditis is presented in this article.
Subject(s)
Pericarditis, Constrictive , Adult , Humans , Male , Pericarditis, Constrictive/diagnosis , Pericarditis, Constrictive/surgeryABSTRACT
Valvular Heart Disease (VHD) is an important cardiovascular problem in the adult population. The knowledge of the physiology involved, prompt recognition and diagnosis are of paramount importance for the primary care physician who is in the front line of patient care. This article is the second of a series of two that deals with valvular problems in the adults in concise and practical form (11). Each topic will be presented using the following format: description, etiology, pathophysiology, natural history, essential of diagnosis and management. In this second and final article we will discuss aortic valve disorders.
Subject(s)
Aortic Valve Insufficiency/therapy , Aortic Valve Stenosis/therapy , Adult , Aortic Valve Insufficiency/diagnosis , Aortic Valve Insufficiency/physiopathology , Aortic Valve Stenosis/diagnosis , Aortic Valve Stenosis/physiopathology , Clinical Trials as Topic , Echocardiography , Electrocardiography , HumansABSTRACT
Valvular Heart Disease (VHD) is an important cardiovascular problem in the adult population. The knowledge of the physiology involved, prompt recognition and diagnosis are of paramount importance for the primary care physician who is in the front line of patient care. This article is the first of a series of two that will discuss valvular problems in the adults in concise and practical form. Each topic will be presented using the following format: description, etiology, pathophysiology, natural history, essential of diagnosis and management. In this first article we will discuss mitral valve disorders including mitral valve prolapse (MVP).
Subject(s)
Mitral Valve Insufficiency , Mitral Valve Prolapse , Mitral Valve Stenosis , Adult , Age Factors , Aged , Catheterization , Disease Progression , Echocardiography , Echocardiography, Doppler , Electrocardiography , Heart Valve Prosthesis Implantation , Humans , Mitral Valve Insufficiency/diagnosis , Mitral Valve Insufficiency/drug therapy , Mitral Valve Insufficiency/physiopathology , Mitral Valve Insufficiency/surgery , Mitral Valve Insufficiency/therapy , Mitral Valve Prolapse/complications , Mitral Valve Prolapse/diagnosis , Mitral Valve Stenosis/diagnosis , Mitral Valve Stenosis/diagnostic imaging , Mitral Valve Stenosis/drug therapy , Mitral Valve Stenosis/physiopathology , Mitral Valve Stenosis/surgery , Mitral Valve Stenosis/therapy , Primary Health Care , Radiography, ThoracicABSTRACT
Se describe la situación actual con respecto a las emisiones a la atmósfera de las centrales térmicas de electricidad, que en Argentina representan la mitad de la potencia instalada. Se ilustra con cuadros, la estadística a raiz de las mediciones realizadas durante 1994 y parte de 1995
Subject(s)
Atmosphere , Industry , Air PollutionABSTRACT
Se describe la situación actual con respecto a las emisiones a la atmósfera de las centrales térmicas de electricidad, que en Argentina representan la mitad de la potencia instalada. Se ilustra con cuadros, la estadística a raiz de las mediciones realizadas durante 1994 y parte de 1995
Subject(s)
Air Pollution , Atmosphere , IndustryABSTRACT
Reportamos el caso de un infante de nueve meses de edad referído al Hospital Pediátrico Universitario con pulmonía. En admisión el paciente presentó angustia respiratoria, linfadenipatía generalizada y hepatoesplenomegalia. Infección simultánea con Mycobacterium tuberculosis y el Virus de Immunodeficiencia Humana (HIV) fue documentada. La epidemiología, el diagnóstico y manejo de niños con el Síndrome de Immunodeficiencia Adquirida (SIDA) se discuten, se presentan recomendaciones en el manejo de niños con infección combinada de HIV y tuberculosis