ABSTRACT
Asia has a growing diabetic population. Linagliptin, a member of dipeptidyl peptidase-4 inhibitor class, is unique in its nonlinear pharmacokinetics with the characteristics of rapid attainment of steady state, little accumulation, predominantly nonrenal route of elimination, prolonged terminal half-life, and sustained inhibition of dipeptidyl peptidase-4 enzyme. No clinically relevant difference in pharmacokinetics was observed between Asians and non-Asians. The management of type 2 diabetes is increasingly challenging with the progression of disease, especially with the requirements of minimal hypoglycemia, weight gain, fluid retention, and other adverse effects. Linagliptin was efficacious and well-tolerated in Asian type 2 diabetes patients with or without renal or hepatic dysfunctions, comparable to that in Caucasians. This review will focus on the usage of linagliptin in clinical studies in Asians.
ABSTRACT
Soluble microbial products (SMP), a majority of organic matter in effluents, play a key role in membrane fouling. A series of filtration experiments were conducted, and demonstrated that the flux decrement rate was in order of cellulose acetate membrane (CA, 65.4%), polyvinylidene fluoride (PVDF, 47.9%) and polyether sulfones (PES, 29.2%). Results showed that the fouling behavior of membrane should be predicted from the combined knowledge of solution chemistry, surface chemical properties and surface morphology. To better understand the interactions between the SMP and different membranes, a technique for reconstructing the membrane surface topology was developed on the basis of statistical parameters obtained from atomic force microscopy. The interaction energy, represented by extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) potential, was calculated by surface element integration, allowing exploring the interaction energy profiles for different surfaces and providing considerable insights into the role of such interactions on the macroscopic fouling behavior. The resulting interaction energy differed considerably from the corresponding interaction between perfectly smooth surfaces. The great influence of protrusion on the membrane surface was to reduce the primary energy barrier height, thus rendering rough surface more favorable for deposition. An attractive energy region was immediately surrounded by each positive asperity as demonstrated in the roughness-engendered interaction energy maps. As the SMP approached closer to the membrane, they had a high probability of getting trapped in the attractive energy region, leading to a more rapid loss of flux than smooth membrane.
