Uso indiscriminado de sucedaneos de la leche materna en Bolivia y su impacto en la economía familiar / Indiscriminate use of breast milk substitutes and its impact on the Bolivian family economy

OBJETIVO: Estimar el presupuesto mensual que las familias destinan a la lactancia artificial de infantes en Bolivia analizando algunos factores sociales y epidemiológicos relacionados a la lactancia materna. MATERIAL Y MÉTODOS: Se realizaron encuestas a madres asistentes a consulta pediátrica del Hospital del Niño Dr. Ovidio Aliaga Uria, hospital universitario de tercer nivel de la ciudad de La Paz, que incluyeron sólo a madres que daban de lactar a bebés menores de un año (infantes), investigando el tipo de lactancia, el uso de fórmulas; estimando el costo de cada una de las diversas fórmulas utilizadas, calculando el volumen requerido, y el presupuesto mensual estimado, necesario para invertirlo exclusivamente para leche artificial. RESULTADOS: En el grupo estudio de infantes entre 0 a 6 meses de edad se comprobó que solo18% de infantes recibe lactancia exclusiva, 58% recibe lactancia mixta y 24% usa fórmulas de manera exclusiva. En el grupo de 6 a 12 meses de edad reciben lactancia exclusiva 8%, lactancia mixta 63% y lactancia en base a formula 29%. Los primeros 6 meses se utiliza un promedio de 30 latas de leche de formula implicando un gasto de entre Bs.5.530 bs (USD 801.-) si se compra en farmacias o supermercados y Bs. 5,202 (USD 754.) si se compra en mercado libre informal. En cuanto al uso de números de empaque o latas en los siguientes meses el número total es de 36 latas, implicando un costo de Bs. 6,936 (USD 1.005.-), si se compra exclusivamente en farmacias y 6,660 bs en mercado libre.

OBJECTIVE: To estimate proportion of the monthly family budget allocated for artificial feeding of infants and discuss the social and some epidemiological factors related to breastfeeding. METHODS: An operative survey has been conducted interviewing mothers attending out patients pediatric Unit of Dr. Ovidio Aliaga Uria Children's Hospital, which included only interviews to mothers breastfeeding just infants under one year, searching data about type of feeding, preferences of formula; cost of each of the different formulas , volume of formula recommended to use monthly budget. RESULTS: in the group of 0-6 months of age 18% of mothers offer exclusive breastfeeding, while mixed feeding is preferred by 58% and 24% use exclusively just formula. In the group of babies of 6 to 12 months 8% receive breast milk, while , 63% offer mixed breastfeeding and formulas, and just formulas in offer to 29%. The first 6 months an average of 30 cans are consumed, involving an estimate expenditure of Bs. 5.530.- (USD 801.-) and Bs. 5.202 (USD 754.-) in the next 6 months, depending on the formula brand, infant age, type of feeding bottle used

Long-circulating PEGylated manganese ferrite nanoparticles for MRI-based molecular imaging.

Magnetic resonance based molecular imaging has emerged as a very promising technique for early detection and treatment of a wide variety of diseases, including cancer, neurodegenerative disorders, and vascular diseases. The limited sensitivity and specificity of conventional MRI are being overcome by the development of a new generation of contrast agents, using nanotechnology approaches, with improved magnetic and biological properties. In particular, for molecular imaging, high specificity, high sensitivity, and long blood circulation times are required. Furthermore, the lack of toxicity and immunogenicity together with low-cost scalable production are also necessary to get them into the clinics. In this work, we describe a facile, robust and cost-effective ligand-exchange method to synthesize dual T1 and T2 MRI contrast agents with long circulation times. These contrast agents are based on manganese ferrite nanoparticles (MNPs) between 6 and 14 nm in size covered by a 3 kDa polyethylene glycol (PEG) shell that leads to a great stability in aqueous media with high crystallinity and magnetization values, thus retaining the magnetic properties of the uncovered MNPs. Moreover, the PEGylated MNPs have shown different relaxivities depending on their size and the magnetic field applied. Thus, the 6 nm PEGylated MNPs are characterized by a low r2/r1 ratio of 4.9 at 1.5 T, hence resulting in good dual T1 and T2 contrast agents under low magnetic fields, whereas the 14 nm MNPs behave as excellent T2 contrast agents under high magnetic fields (r2 = 335.6 mM(-1) s(-1)). The polymer core shell of the PEGylated MNPs minimizes their cytotoxicity, and allows long blood circulation times. This combination of cellular compatibility and excellent T2 and r2/r1 values under low magnetic fields, together with long circulation times, make these nanomaterials very promising contrast agents for molecular imaging.