Novel equation to determine the hepatic triglyceride concentration in humans by MRI: diagnosis and monitoring of NAFLD in obese patients before and after bariatric surgery

Background: Non-alcoholic fatty liver disease (NAFLD) is caused by abnormal accumulation of lipids within liver cells. Its prevalence is increasing in developed countries in association with obesity, and it represents a risk factor for non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma. Since NAFLD is usually asymptomatic at diagnosis, new non-invasive approaches are needed to determine the hepatic lipid content in terms of diagnosis, treatment and control of disease progression. Here, we investigated the potential of magnetic resonance imaging (MRI) to quantitate and monitor the hepatic triglyceride concentration in humans. Methods: A prospective study of diagnostic accuracy was conducted among 129 consecutive adult patients (97 obesity and 32 non-obese) to compare multi-echo MRI fat fraction, grade of steatosis estimated by histopathology, and biochemical measurement of hepatic triglyceride concentration (that is, Folch value). Results: MRI fat fraction positively correlates with the grade of steatosis estimated on a 0 to 3 scale by histopathology. However, this correlation value was stronger when MRI fat fraction was linked to the Folch value, resulting in a novel equation to predict the hepatic triglyceride concentration (mg of triglycerides/g of liver tissue = 5.082 + (432.104 * multi-echo MRI fat fraction)). Validation of this formula in 31 additional patients (24 obese and 7 controls) resulted in robust correlation between the measured and estimated Folch values. Multivariate analysis showed that none of the variables investigated improves the Folch prediction capacity of the equation. Obese patients show increased steatosis compared to controls using MRI fat fraction and Folch value. Bariatric surgery improved MRI fat fraction values and the Folch value estimated in obese patients one year after surgery. Conclusions: Multi-echo MRI is an accurate approach to determine the hepatic lipid concentration by using our novel equation, representing an economic non-invasive method to diagnose and monitor steatosis in humans.

Fármacos microencapsulados para el tratamiento del glaucoma

Sobre la base de la problemática de los tratamientos terapéuticos del glaucoma, en especial cuando se administran en forma de gotas oculares y dado el empleo de los beta-bloqueantes como el grupo de fármacos utilizados como primera opción de tratamiento; y teniendo en cuenta las ventajas que ofrece la microencapsulación de fármacos en el sector farmacéutico y el uso de las ciclodextrinas como agentes encapsulantes, el objetivo de este trabajo se centra en la microencapsulación del fármaco beta-bloqueante (timolol) con HP-β-CD en agua para el tratamiento del glaucoma. Para la consecución de este objetivo se ha seleccionado en base a los métodos de encapsulación y agentes encapsulantes descritos en la bibliografía las CDs como agentes encapsulantes, concretamente la HP-β-CD por su mayor facilidad para formar complejos de inclusión y por su baja toxicidad y se ha elegido el método de encapsulación por inclusión, debido a las características mencionadas y a que las propiedades de los principios activos son potenciadas por este método