RESUMEN
Hydrogels are a class of biomaterials that can provide a three-dimensional (3D) environment capable of mimicking the extracellular matrix of native tissues. In this chapter, we present a method to generate electrospun nanofibers for the purpose of reinforcing hydrogels. The addition of electrospun fibers can be used to improve the mechanical properties of hydrogels and broaden their range of applications. First, the polymer for making the electrospun fibers is formulated using chloroform/ethanol, polycaprolactone (PCL), polyethylene glycol (PEG), and polyethylene glycol diacrylate (PEGDA). Second, the polymer is used to generate thin electrospun nanofibers by an electrospinning technique using aluminum foil as a collector, which acts as the conductive substrate that collects the charged fibers. Third, the resulting electrospun fibers undergo a filtration process using nylon membrane filters, followed by lyophilization, ensuring complete removal of water from the sample.
Asunto(s)
Hidrogeles , Nanofibras , Polietilenglicoles , Nanofibras/química , Polietilenglicoles/química , Hidrogeles/química , Materiales Biocompatibles/química , Humanos , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Poliésteres/química , Andamios del Tejido/química , Ingeniería de Tejidos/métodosRESUMEN
The field of small-diameter vascular grafts remains a challenge for biomaterials scientists. While decades of research have brought us much closer to developing biomimetic materials for regenerating tissues and organs, the physiological challenges involved in manufacturing small conduits that can transport blood while not inducing an immune response or promoting blood clots continue to limit progress in this area. In this short review, we present some of the most recent methods and advancements made by researchers working in the field of small-diameter vascular grafts. We also discuss some of the most critical aspects biomaterials scientists should consider when developing lab-made small-diameter vascular grafts.
RESUMEN
Twenty years have passed since the emergence of hantavirus zoonosis in Panama at the beginning of this millennium. We provide an overview of epidemiological surveillance of hantavirus disease (hantavirus pulmonary syndrome and hantavirus fever) during the period 1999-2019 by including all reported and confirmed cases according to the case definition established by the health authority. Our findings reveal that hantavirus disease is a low-frequency disease, affecting primarily young people, with a relatively low case-fatality rate compared to other hantaviruses in the Americas (e.g., ANDV and SNV). It presents an annual variation with peaks every 4-5 years and an interannual variation influenced by agricultural activities. Hantavirus disease is endemic in about 27% of Panama, which corresponds to agroecological conditions that favor the population dynamics of the rodent host, Oligoryzomys costaricensis and the virus (Choclo orthohantavirus) responsible for hantavirus disease. However, this does not rule out the existence of other endemic areas to be characterized. Undoubtedly, decentralization of the laboratory test and dissemination of evidence-based surveillance guidelines and regulations have standardized and improved diagnosis, notification at the level of the primary care system, and management in intensive care units nationwide.
Asunto(s)
Enfermedades Transmisibles , Infecciones por Hantavirus , Síndrome Pulmonar por Hantavirus , Fiebre Hemorrágica con Síndrome Renal , Orthohantavirus , Animales , Infecciones por Hantavirus/epidemiología , Síndrome Pulmonar por Hantavirus/epidemiología , Panamá/epidemiología , Roedores , SigmodontinaeRESUMEN
In Panama, hantavirus pulmonary syndrome (HPS) is caused by Choclo virus, a species phylogenetically related to Andes and Maporal viruses. Up to 60% of the population has been positive for specific serum antibody in community-based surveys, but mortality is very uncommon. In four western Panama clinics, we tested individuals presenting with a severe febrile prodrome for acute hantavirus (HV) infection by immunoglobulin M enzyme-linked immunosorbent assay and reverse transcription polymerase chain reaction as well as clinically similar infections, such as dengue and leptospirosis. From 2006 to 2009, at least 21% of 117 patients diagnosed with HV infection had HV Fever (HF) with no evidence of pulmonary edema (no respiratory distress or radiographic lung infiltrates), and 44% of patients had very mild HPS (radiographic pulmonary edema but no respiratory insufficiency). HV infection caused by Choclo virus in Panama presents often as HF, which contrasts with HV in the Americas but is consistent with the high seroprevalence in endemic regions.
Asunto(s)
Síndrome Pulmonar por Hantavirus/diagnóstico , Síndrome Pulmonar por Hantavirus/epidemiología , Fiebre Hemorrágica con Síndrome Renal/diagnóstico , Fiebre Hemorrágica con Síndrome Renal/epidemiología , Orthohantavirus/aislamiento & purificación , Adolescente , Adulto , Anciano , Anticuerpos Antivirales/sangre , Niño , Preescolar , Femenino , Orthohantavirus/genética , Humanos , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Panamá/epidemiología , ARN Viral/aislamiento & purificación , Estudios Seroepidemiológicos , Adulto JovenRESUMEN
El objetivo del presente trabajo es presentar 8 casos con diagnóstico de hydrops fetalis (HF) que han surgido como consecuencia de diversas patologías y mostrar las posibles alternativas de patologías y mostrar las posibles alternativas de utilidad para su manejo y estudio. Se estudiaron 1200 pacientes embarazadas que acudieron a la Unidad de Perinatología de la Universidad de Carabobo entre 07 de Enero de 1996 y 23 de Agosto de 2001, diagnosticándose 8 casos de HF: Uno inmunológico en multípara de 26 años, embarazo de 28 semanas, zona de alto riesgo de Queenan, III de Liley, transfusión intravascular, óbito fetal a las 30 semanas; tres con higroma quístico en pacientes de 36, 26 y 29 años en quienes la amniocentesis genética reportó: dos manosomía XO y una trisomía 21, diagnosticadas a las 20, 16 y 18 semanas de gestación respectivamente; un caso asociado a taquiarritmia fetal en I gesta de 18 años, embarazo de 35 semanas, parto normal a las 37 semanas y diagnóstico postnatal de taquicardia paroxística supraventricular; otro con diagnostico de displasia esquelética del tipo enanismo tanatofórico acompañado de macroglosia en IV gesta, III para, embarazo de 32 semanas complicado con polihidramnios, y dos idiopáticos en embarazos de 20 y 27 semanas, el primero con resolución espontánea a las 29 semanas y el ultimo resultando en óbito fetal. Nuestra incidencia de HF fue de 1/150 embarazos, siendo la mayoría de ellos (88 por ciento) de origen no inmunológico, lo cual alerta sobre la multiplicidad de causas y la variada interacción de factores que han de ser considerados para tratar de definir su mecanismo fisiopatológico y el abordaje clínico adecuado