301 research outputs found
Osteoartritis neonatal de la columna dorsal, con presentación de tumor mediastinal posterior :descripción de un caso y revisión de la bibliografía
Un RN de 33 días de vida presentó sintomatología y hallazgos radiográficos compatibles con un tumor de mediastino posterior. Antecedentes de fiebre recurrente y prolongada y de retraso en la ganancia ponderal no recibieron la importancia debida, lo cual hubiera facilitado el diagnóstico de certeza. Este fue confirmado en cirugía, al encontrarse un foco osteoartrítico en D4. No existen comunicaciones previas asociando estas dos infrecuentes entidades clínicas
Valoración de la citología exfoliativa como factor de predicción en lesiones de la mucosa oral.
El objetivo de este estudio fue inmunomarcar las oncoproteínas CK14, p53, p21 y Bc1-2 a fin de evaluar la magnitud de su
expresión en lesiones estomatológicas premalignas y malignas en el epitelio oral, y comparar esta expresión con alteraciones
en las citologías exfoliativas de los mismos pacientes. Se estudiaron biopsias y citologías de trece sujetos con líquenes
plano oral con y sin infección con Virus Papiloma Humano (HPV), leucoplasias, y carcinomas espinocelulares diagnosticados
clínicamente y confirmados por estudios anatomopatológicos. Las lesiones producidas por líquen oral plano presentaron
células binucleadas y con coloración naranja; en las lesiones leucoplásicas sólo se observó tinción naranja mientras que en
carcinomas espinosos y en infecciones por Virus Papiloma Humano además se observaron coilocitos, células inflamatorias,
aumento del volumen nuclear y microorganismos patogénicos. Las proteínas CK14, p53, p21 y Bcl-2 se encontraron modificadas en leucoplasias, líquenes planos orales y cáncer. Las alteraciones citológicas y la inmunomarcación positiva o sobreexpresión de la citoqueratina CK14 en los estratos epiteliales superficiales deberían ser suficientes indicadores de transformaciones malignas como para realizar exámenes posteriores.publishedVersio
Au Nanoparticles-Mesoporous TiO2 Thin Films Composites as SERS Sensors: A Systematic Performance Analysis
The combination of plasmonic nanoparticles and mesoporous materials is of much interest in applications such as sensing or catalysis. The production of such hybrid materials can be done in various ways, leading to different architectures. We present a comparative study of the SERS performance of different nanocomposite architectures comprising mesoporous TiO2 thin films and Au nanoparticles (NPs). The selection of TiO2 as mesoporous support material was based on its high chemical and mechanical stability. Au NPs of different sizes and shapes were placed at different locations of the composite and used as a plasmonic material compatible with the synthesis conditions of the mesoporous films, displaying a high chemical stability. Using p-nitrothiophenol as a molecular probe, we evaluated the performance toward surface-enhanced Raman scattering (SERS) sensing, on the basis of minimum acquisition time, spot-to-spot reproducibility, and limit of detection. The obtained results indicate that each platform features different sensing capabilities. While systems comprising Au NPs within the mesopores allow working with low acquisition times and present high signal uniformity, only a detection limit of micromolar was achieved. On the other hand, those systems made of branched Au NPs covered with mesoporous films require low acquisition times and can achieve detection limits as low as 10 pM, but signal uniformity is compromised. We propose that careful comparison of different SERS platforms based on Au NPs and mesoporous thin films will facilitate selecting an appropriate configuration for any desired application.Fil: Zalduendo, María Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; ArgentinaFil: Langer, Judith. Centro de Investigación Cooperativa en Biomateriales; EspañaFil: Giner Casares, Juan J.. Centro de Investigación Cooperativa en Biomateriales; EspañaFil: Halac, Emilia B.. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; ArgentinaFil: Soler Illia, Galo Juan de Avila Arturo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martin. Instituto de Nanosistemas; ArgentinaFil: Liz Marzán, Luis M.. Centro de Investigación Cooperativa en Biomateriales; España. Basque Foundation for Science; EspañaFil: Angelome, Paula Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentin
New Superhard Phases for 3D C60-based Fullerites
We have explored new possible phases of 3D C60-based fullerites using
semiempirical potentials and ab-initio density functional methods. We have
found three closely related structures - two body centered orthorhombic and one
body centered cubic - having 52, 56 and 60 tetracoordinated atoms per molecule.
These 3D polymers result in semiconductors with bulk moduli near 300 GPa, and
shear moduli around 240 GPa, which make them good candidates for new low
density superhard materials.Comment: To be published in Physical Review Letter
Nuclear medicine procedures and the evaluation of male sexual organs: a short review
Sexuality consists of three aspects that are interrelated and inseparable, biological, physiological and social. The biological aspect considers the individual's capability to give and to receive pleasure. In consequence, it covers the functionality of the sexual organs and the physiology of human sexual response cycle. Diagnostic imaging modalities, such as single photon emission computed tomography (SPECT) and positron emission tomography (PET) have been used to evaluate clinical disorders of the male reproductive system. PET and SPECT procedures basically involve the administration of a radiopharmaceutical that has a higher uptake in a specific tumor or tissue. The aim of this brief review is to present some radiopharmaceuticals that have been used in the clinical evaluation of the male sexual organs (testes, prostate, seminal vesicles, penis) related with male sexuality. This information could be useful in better understanding the male sexual response cycle, as well as the sexual disorders, when considering the male sexual organs and the pelvic floor. Moreover, the findings obtained with PET and SPECT imaging could help to evaluate the efficacy of clinical results of therapeutic procedures. In conclusion, the knowledge from these images could aid in better understanding the physiology of the different organs related with sexuality. Furthermore, they could be important tools to evaluate the physiological integrity of the involved organs, to improve clinical strategies and to accompany the patients under treatment
Diagnosis of neuronal ceroid lipofuscinosis type 2 (CLN2 disease): Expert recommendations for early detection and laboratory diagnosis
Neuronal ceroid lipofuscinoses (NCLs) are a heterogeneous group of lysosomal storage disorders. NCLs include the rare autosomal recessive neurodegenerative disorder neuronal ceroid lipofuscinosis type 2 (CLN2) disease, caused by mutations in the tripeptidyl peptidase 1 (TPP1)/CLN2 gene and the resulting TPP1 enzyme deficiency. CLN2 disease most commonly presents with seizures and/or ataxia in the late-infantile period (ages 2-4), often in combination with a history of language delay, followed by progressive childhood dementia, motor and visual deterioration, and early death. Atypical phenotypes are characterized by later onset and, in some instances, longer life expectancies. Early diagnosis is important to optimize clinical care and improve outcomes; however, currently, delays in diagnosis are common due to low disease awareness, nonspecific clinical presentation, and limited access to diagnostic testing in some regions. In May 2015, international experts met to recommend best laboratory practices for early diagnosis of CLN2 disease. When clinical signs suggest an NCL, TPP1 enzyme activity should be among the first tests performed (together with the palmitoyl-protein thioesterase enzyme activity assay to rule out CLN1 disease). However, reaching an initial suspicion of an NCL or CLN2 disease can be challenging; thus, use of an epilepsy gene panel for investigation of unexplained seizures in the late-infantile/childhood ages is encouraged. To confirm clinical suspicion of CLN2 disease, the recommended gold standard for laboratory diagnosis is demonstration of deficient TPP1 enzyme activity (in leukocytes, fibroblasts, or dried blood spots) and the identification of causative mutations in each allele of the TPP1/CLN2 gene. When it is not possible to perform both analyses, either demonstration of a) deficient TPP1 enzyme activity in leukocytes or fibroblasts, or b) detection of two pathogenic mutations in trans is diagnostic for CLN2 disease
Guidelines for incorporating scientific knowledge and practice on rare diseases into higher education: neuronal ceroid lipofuscinoses as a model disorder model disorder.
This article addresses the educational issues associated with rare diseases (RD) and in particular the Neuronal
Ceroid Lipofuscinoses (NCLs, or CLN diseases) in the curricula of Health Sciences and Professional's Training
Programs. Our aim is to develop guidelines for improving scientific knowledge and practice in higher education
and continuous learning programs.
Rare diseases (RD) are collectively common in the general populationwith 1 in 17 people affected by a RDin their
lifetime. Inherited defects in genes involved in metabolism are the commonest group of RD with over 8000
known inborn errors of metabolism. The majority of these diseases are neurodegenerative including the NCLs.
Any professional training program on NCL must take into account the medical, social and economic burdens
related to RDs. To address these challenges and find solutions to themit is necessary that individuals in the government
and administrative authorities, academia, teaching hospitals and medical schools, the pharmaceutical
industry, investment community and patient advocacy groups all work together to achieve these goals.
The logistical issues of including RD lectures in university curricula and in continuing medical education should
reflect its complex nature. To evaluate the state of education in the RD field, a summary should be periodically up
dated in order to assess the progress achieved in each country that signed up to the international conventions
addressing RD issues in society. It is anticipated that auditing current practice will lead to higher standards and
provide a framework for those educators involved in establishing RD teaching programs world-wide.publishedVersio
Relational Contracts and Organizational Capabilities
A large literature identifies unique organizational capabilities as a potent source of competitive advantage, yet our knowledge of why capabilities fail to diffuse more rapidly—particularly in situations in which competitors apparently have strong incentives to adopt them and a well-developed understanding of how they work—remains incomplete. In this paper we suggest that competitively significant capabilities often rest on managerial practices that in turn rely on relational contracts (i.e., informal agreements sustained by the shadow of the future). We argue that one of the reasons these practices may be difficult to copy is that effective relational contracts must solve the twin problems of credibility and clarity and that although credibility might, in principle, be instantly acquired, clarity may take time to develop and may interact with credibility in complex ways so that relational contracts may often be difficult to build
The diagnostic work up of growth failure in secondary health care; An evaluation of consensus guidelines
Background: As abnormal growth might be the first manifestation of undetected diseases, it is important to have accurate referral criteria and a proper diagnostic work-up. In the present paper we evaluate the diagnostic work-up in secondary health care according to existing consensus guidelines and study the frequency of underlying medical disorders. Methods: Data on growth and additional diagnostic procedures were collected from medical records of new patients referred for short stature to the outpatient clinics of the general paediatric departments of two hospitals (Erasmus MC - Sophia Children's Hospital, Rotterdam and Spaarne Hospital, Haarlem) between January 1998 and December 2002. As the Dutch Consensus Guideline (DCG) is the only guideline addressing referral criteria as well as diagnostic work-up, the analyses were based on its seven auxological referral criteria to determine the characteristics of children who are incorrectly referred and the adequacy of workup of those who are referred. Results: Twenty four percent of children older than 3 years were inappropriately referred (NCR). Of the correctly referred children 74-88% were short corrected for parental height, 40-61% had a height SDS <-2.5 and 21% showed height deflection (Δ HSDS < -0.25/yr or Δ HSDS < -1). In none of the children a complete detailed routine diagnostic work up was performed and in more than 30% no routine laboratory examination was done at all. Pathologic causes of short stature were found in 27 children (5%). Conclusion: Existing guidelines for workup of children with suspected growth failure are poorly implemented. Although poorly implemented the DCG detects at least 5% pathologic causes of growth failure in children referred for short stature. New guidelines for referral are required with a better sensitivity and specificity, wherein distance to target height should get more attention. The general diagnostic work up for short stature should include testing for celiac disease in all children and for Turner syndrome in girls
Efficacy of recombinant thrombomodulin for DIC after deceased donor liver transplantation: a case report
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