RESUMEN
Certain spatial distributions of water inside partially filled containers can significantly reduce the bounce of the container. In experiments with containers filled to a volume fraction Ï, we show that rotation offers control and high efficiency in setting such distributions and, consequently, in altering bounce markedly. High-speed imaging evidences the physics of the phenomenon and reveals a rich sequence of fluid-dynamics processes, which we translate into a model that captures our overall experimental findings.
Asunto(s)
Hidrodinámica , Física , AguaRESUMEN
Pulmonary embolism is a very infrequent event in previously healthy children, particularly in the outpatient scenario. This report involves a 7-year-old girl who presented to the emergency room after syncope. A prompt diagnostic workup showed a massive pulmonary embolism. A timely treatment initiation permitted a good and rapid response. She represented a diagnostic and treatment challenge, mainly because of the atypical presentation and the absence of known risk factors. Finally, a thorough study uncovered a nephrotic-range urine protein loss. At the beginning, the patient did not meet the whole nephrotic syndrome diagnostic requirements. The complete thombophilic study was normal. The clinical presentation, epidemiology, diagnostic tools and the treatment of pulmonary embolism are reviewed. We also discuss a recently described risk factor, present in our patient, as a potential role in the development of pulmonary embolism.
Asunto(s)
Embolia Pulmonar/diagnóstico , Síncope/etiología , Anticoagulantes/uso terapéutico , Niño , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Fibrinógeno/análisis , Fibrinolíticos/uso terapéutico , Heparina/uso terapéutico , Humanos , Hipertensión Pulmonar/diagnóstico , Síndrome Nefrótico/diagnóstico , Plasma , Embolia Pulmonar/terapia , Activador de Tejido Plasminógeno/uso terapéuticoRESUMEN
Advances in the generation of suitable thermosensitive hydrogels for the delivery of cells in neural tissue engineering demonstrate a delicate relationship between physical properties and capabilities to promote cell proliferation and differentiation. To improve the properties of these materials, it is possible to add liposomes for the controlled release of bioactive elements, which in turn can affect the physical and biological properties of the hydrogels. In the present investigation, different hydrogels based on Pluronic F127 have been formulated with the incorporation of chitosan and two types of liposomes of two different sizes. The rheological and thermal properties and their relation with the neurite proliferation and growth of the PC12 cell line were evaluated. Our results show that the incorporation of liposomes modifies the properties of the hydrogels dependent on the concentration of chitosan and the lipid type in the liposomes, which directly affect the capabilities of the hydrogels to promote the viability and differentiation of PC12 cells.
RESUMEN
BACKGROUND: Down syndrome (DS) is the most common autosomal chromosomal disorder. Epidermolysis bullosa (EB) is a rare genodermatosis characterized by skin and mucous membrane fragility, with formation of blisters and erosions after minor trauma. Dystrophic EB (DEB) is inherited as an autosomal dominant (DDEB) or recessive (RDEB) trait. Both forms are caused by mutations in COL7A1, the gene coding for the type VII collagen. We report a patient affected by both conditions: DS and DDEB. METHODS: A patient with DS developed generalized blisters at the age of three months. Cytogenetic study was performed to confirm DS. Skin biopsies were examined with immunohistochemical and electron microscopy techniques to determine EB subtype. Genomic DNA was extracted from peripheral blood samples. COL7A1 mutations were screened by heteroduplex analysis using conformation-sensitive gel electrophoresis and sequencing. RESULTS: Karyotype analysis revealed trisomy 21. Histological study agreed with a DEB diagnosis. Mutational analysis showed a heterozygous c.6127G>T mutation in COL7A1, which is compatible with DDEB. Parental study suggests that c.6127G>T arises as a de novo mutation. CONCLUSIONS: This report demonstrates that EB can be associated with other common conditions and reports the case of a patient who suffered two de novo independent genetic conditions. It also contributes to expanding the knowledge and database of clinical and molecular aspects of DDEB.