To design and fabricate next-generation tissue engineering materials, the understanding of cell responses to material surfaces is required. Surface topography presents powerful cues for cells and can strongly influence cell morphology, adhesion, and proliferation, but the mechanisms mediating this cell response remain unclear. In this report, we have investigated the effects of nanoroughness assemblies of silk fibroin protein membranes and RGD sequences fabricated from two different silk fibroin sources, that is, mulberry (Bombyx mori) and nonmulberry (Antheraea mylitta), on cytoskeletal organization, proliferation, and viability using primary rat bone marrow cells. To vary surface roughness, silk fibroin substrates were treated with graded ethanol (50%-100% v/v) to produce nanoarchitectures in the range of 1-12 nm height. The graded alcohol treatments have been found to produce nanoscale topographies of reproducible height in a much faster and cheaper way. The results showed no difference in cell proliferation within the same treatment groups for both silk types. However, a change in cell response in terms of good cytoskeleton organization, actin development, cell spreading, and strong binding to substratum using A. mylitta fibroin protein films having RGD sequences was observed. This finding provides the information that the nanoroughness affects cellular processes in a cell-specific manner and may be helpful for the development of smart silk-based biomaterials especially for directing cell differentiation and regenerative therapies.

Biodrugs (biologics) are much more complex than chemically synthesized drugs because of their structural heterogeneity and interactions within a given biologic system. The manufacturing process in the biodrug industry varies with each type of molecule and is far more elaborate and stringent due to the use of living organisms and complex substrates. Product purity and altered structural characteristics leading to potential immunogenicity have often been of concern when establishing quality and safety in the use of biodrugs. Regulatory compliance in manufacturing and commercialization of biodrugs involves quality control, quality assurance, and batch documentation. Many factors such as host cell development, cell bank establishment, cell culture, protein production, purification, analysis, formulation, storage, and handling are critical for ensuring the purity, activity, and safety of the finished product. Good Manufacturing Practice (GMP) for biodrugs has been developed in certain regions such as the EU, US, and Japan. Due to differences in manufacturing methods and systems, product-specific GMP guidelines are evolving. In general, there are variations in GMP guidelines between countries, which lead to difficulty for the manufacturers in conforming to different standards, thus entailing delays in the commercialization of biodrugs. There is a need to develop a unified regulatory guideline for biodrug manufacturing across various countries, which would be helpful in the marketing of products and trade. This review deals with the comparative framework and analysis of GMP regulation of biodrugs.

Mango fruits from different varieties vary in aroma and taste. In this study, methanol extracts of fruit pulps obtained from seven Indian varieties of Mangifera indica (Amrapali, Fazli, Golapkhas, Gopalbhog, Himsagar, Langra, and Mohanbhog) were profiled using a metabolomics approach. Chemometric methods were used to understand the contribution of metabolites to varietal differences. The extracts were also assayed for pancreatic lipase inhibitory activities in vitro. All the pulp extracts were analyzed by GC-MS and HPLC to detect their metabolites. In sum, 63 metabolites were identified. The varieties were distinctly different chemically in terms of the identified metabolites, as revealed by principal component analysis (PCA) and partial least squaresdiscriminant analysis (PLS-DA). From the biplot and VIP scores, it was observed that in addition to some organic acids, amino acids, sugars, and phenolic constituents (e.g., benzene-1,2,4-triol, mangiferin, and pyrogallol) contributed to this variation. All the varieties also inhibited pancreatic lipase in a dose-dependent manner. Gallic acid (IC 50 value 0.47 nM) and 4-hydroxy benzoic acid (IC 50 value 1.15 nM) showed high anti-lipase activity. Three amino acids (L-proline (IC 50 value 0.01 µM), L-alanine (IC 50 value 0.14 µM) and aspartic acid (IC 50 value 0.02 µM)), and the inorganic acid phosphoric acid (0.02 µM) also showed activity against pancreatic lipase. ARTICLE HISTORY

A theoretical analysis for the problem of wave propagation in arteries is presented. Blood is treated as a Newtonian, viscous incompressible fluid. On the basis of information derived from experimental investigations on the mechanical properties of wall tissues, the arterial wall is considered to be nonlinearly viscoelastic and orthotropic. The analysis is carried out for a cylindrical artery, under the purview of membrane theory, by taking account the effect of initial stresses. The motion of the wall and that of the fluid are assumed to be axisymmetric. Particular emphasis has been paid to the propagation of small amplitude harmonic waves whose wavelength is large compared to the radius of the vessel. By employing the equations of motion of the fluid and those for the wall, together with the equations of continuity, a frequency equation is derived by exploiting the conditions of continuity of the velocity of the arterial wall and that of blood on the endosteal surface of the wall. In order to illustrate the validity of the derived analytical expressions a quantitative analysis is made for the variations of the phase velocities as well as the transmission coefficient with frequency corresponding to different transmural pressures which relate to different initial stresses. Computational results indicate that phase velocities increase with the increase of transmural pressures.

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