A supramolecular synthon approach was exploited to design amorphous solid dispersions (ASDs) of drugs containing an amino aromatic nitrogen moiety and a polyacrylic acid polymer.
Diseases associated with the thyroid gland are one of the most frequently seen endocrine disorders across the globe. Total thyroidectomy is currently the preferred treatment for many thyroid diseases. Controversies exist among surgeons regarding safety of total thyroidectomy due to the risk associated with it like postoperative hypoparathyroidism or recurrent laryngeal nerve damage. Since, in the recent years, the incidence of thyroidectomy is in increasing trend in south Indian population, this review aims to study the available data regarding the appropriateness and safety of total thyroidectomy and compares it with subtotal thyroidectomy and other thyroid surgeries. This is a retrospective comprehensive review of various articles and publications regarding total and partial thyroidectomy performed across the world. Many retrospective studies and few prospective studies suggest that the incidence of transient hypocalcemia is higher after total thyroidectomy than after subtotal thyroidectomy, but the incidence of other complications including recurrent laryngeal nerve palsy and postoperative hematoma is not significantly different between the two procedures. Hence in our review we found that total thyroidectomy is safe and cost effective with low complication rates and provides little significant advantage of being safer procedure compared to subtotal thyroidectomy.
Fenofibrate is mainly used to reduce cholesterol level in patients at risk of cardiovascular disease. Thermal transition study with the help of differential scanning calorimetry (DSC) shows that the aforesaid active pharmaceutical ingredient (API) is a good glass former. Based on our DSC study, the molecular dynamics of this API has been carried out by broadband dielectric spectroscopy (BDS) covering wide temperature and frequency ranges. Dielectric measurements of amorphous fenofibrate were performed after its vitrification by fast cooling from a few degrees above the melting point (Tm=354.11 K) to deep glassy state. The sample does not show any crystallization tendency during cooling and reaches the glassy state. The temperature dependence of the structural relaxation has been fitted by single Vogel–Fulcher–Tamman (VFT) equation. From VFT fit, glass transition temperature (Tg) was estimated as 250.56 K and fragility (m) was determined as 94.02. This drug is classified as a fragile glass former. Deviations of experimental data from Kohlrausch–Williams–Watts (KWW) fits on high-frequency flank of α-peak indicate the presence of an excess wing in fenofibrate. Based on Ngai׳s coupling model, we identified the excess wing as true Johari–Goldstein (JG) process. Below the glass transition temperature one can clearly see a secondary relaxation (γ) with an activation energy of 32.67 kJ/mol.
The critical cooling rate (CR crit ) to prevent drug crystallization during the preparation of nifedipine amorphous solid dispersions (ASDs) was determined through the time−temperature-transformation (TTT) diagram. ASDs were prepared with polyvinylpyrrolidone, hydroxypropylmethyl cellulose acetate succinate, and poly(acrylic acid). ASDs were subjected to isothermal crystallization over a wide temperature range, and the time and temperature dependence of nifedipine crystallization onset time (t C ) was determined by differential scanning calorimetry (DSC) and synchrotron X-ray diffractometry. TTT diagrams were generated for ASDs, which provided the CR crit for the dispersions prepared with each polymer. The observed differences in CR crit could be explained in terms of differences in the strength of interactions. Stronger drug−polymer interactions led to longer t C and decreased CR crit . The effect of polymer concentrations (4−20% w/w) was also influenced by the strength of the interaction. The CR crit of amorphous NIF was ∼17.5 °C/min. Addition of 20% w/w polymer resulted in a CR crit of ∼0.05, 0.2, and 11 °C/min for the dispersions prepared with PVP, HPMCAS, and PAA, respectively.
Soybean protein concentrates were produced by ultrafiltration with a commercial 4-in spiral wound module with a polyvinylidene difluoride membrane. With soy flour suspensions of 2% total solids (TS), protein content could be increased from 50% (dry basis) to 67% by ultrafiltration and/or diafiltration. Soluble sugars could be removed almost completely, but ash content of retentate solids did not decrease significantly. Higher protein contents would require removal of some of the fiber and/or manipulation of the feed environment to reduce solutesolute interactions. Protein yields were 90%. Flux decreased from 78 L/m 2 /h (LMH) with 2% TS soy flour suspension to 22 LMH at 17% TS.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.