| 1. |
- Elbadawi, Mohammed, 1987-, et al.
(författare)
-
Pressure-assisted microsyringe 3D printing of oral films based on pullulan and hydroxypropyl methylcellulose
- 2021
-
Ingår i: International Journal of Pharmaceutics. - : Elsevier. - 0378-5173 .- 1873-3476. ; 595
-
Tidskriftsartikel (refereegranskat)abstract
- Oral films (OFs) continue to attract attention as drug delivery systems, particularly for pedatric and geriatric needs. However, immiscibility between different polymers limits the full potential of OFs from being explored. One example is pullulan (PUL), a novel biopolymer which often has to be blended with other polymers to reduce cost and alter its mechanical properties. In this study, the state-of-the-art in fabrication techniques, three-dimensional (3D) printing was used to produce hybrid film structures of PUL and hydroxypropyl methylcellulose (HPMC), which were loaded with caffeine as a model drug. 3D printing was used to control the spatial deposition of films. HPMC was found to increase the mean mechanical properties of PUL films, where the tensile strength, elastic modulus and elongation break increased from 8.9 to 14.5 MPa, 1.17 to 1.56 GPa and from 1.48% to 1.77%, respectively. In addition, the spatial orientation of the hybrid films was also explored to determine which orientation could maximize the mechanical properties of the hybrid films. The results revealed that 3D printing could modify the mechanical properties of PUL whilst circumventing the issues associated with immiscibility.
|
|
| 2. |
- Fadda, H M, et al.
(författare)
-
Drug Solubility in Luminal Fluids from Different Regions of the Small and Large Intestine of Humans
- 2010
-
Ingår i: Molecular pharmaceutics. - : American Chemical Society (ACS). - 1543-8384 .- 1543-8392. ; 7:5, s. 1527-1532
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of this work was to study the solubility of two drugs with different physicochemical properties in luminal fluids obtained from various regions of the human gastrointestinal (GI) tract and to determine the most important luminal parameters influencing their solubility. Jejunal fluids were aspirated from healthy volunteers via an oral intubation tube. Ileal and colonic fluids were obtained from patients undergoing GI surgery. Stoma fluids were also retrieved from patients. pH and buffer capacity of all fluids were determined. Saturation solubility of prednisolone (unionisable) and mesalamine (5-aminosalicylic acid) (zwitterionic) was measured. Mean solubility of prednisolone in the different luminal fluids was 0.50 mg/mL (±0.05) and did not vary significantly between the different regions of the GI tract (ANOVA, p > 0.05). No correlation between prednisolone solubility and jejunal bile salt content was found. Mesalamine solubility increased down the GI tract: 1.97 (±0.25), 3.26 (±0.08), 6.24 (±1.13) and 7.95 (±0.21) mg/mL in jejunal, ileal, ascending and transverse/descending colonic fluids respectively. Buffer capacity also increased and in one patient was observed to range from 6.4 to 28.6 reaching 44.4 mM/L/pH unit in ileal, ascending and transverse/descending colon fluids respectively. Mesalamine solubility was found to be dependent on both buffer capacity and pH, with buffer capacity being the most important (standardized coefficient β = 0.849, p < 0.0001) compared to pH (β = 0.219, p < 0.05). For drugs delivered as modified release formulations it is important to consider solubility in different regions of the GI tract as significant differences can arise which will ultimately influence drug bioavailability.
|
|
| 3. |
- Lind, Lars, et al.
(författare)
-
Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight NCD Risk Factor Collaboration (NCD-RisC)
- 2021
-
Ingår i: eLife. - : eLife Sciences Publications Ltd. - 2050-084X. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions.
|
|
