Extended release of high molecular weight hydroxypropyl methylcellulose from molecularly imprinted, extended wear silicone hydrogel contact lenses

Biomaterials ◽  
2011 ◽  
Vol 32 (24) ◽  
pp. 5698-5705 ◽  
Author(s):  
Charles J. White ◽  
Matthew K. McBride ◽  
Kayla M. Pate ◽  
Arianna Tieppo ◽  
Mark E. Byrne
2020 ◽  
Vol 3 (8) ◽  
pp. 20-22
Author(s):  
Muhammad Hamza ◽  
Chrishan Gunasekera ◽  
Samar Nahas ◽  
Z CX Lin ◽  
Hatch Mukherjee ◽  
...  

Metabolism ◽  
2008 ◽  
Vol 57 (3) ◽  
pp. 404-409 ◽  
Author(s):  
Eric P. Plaisance ◽  
Peter W. Grandjean ◽  
Brandon L. Brunson ◽  
Robert L. Judd

2013 ◽  
Vol 165 (1) ◽  
pp. 82-89 ◽  
Author(s):  
Hyun Jung Jung ◽  
Michelle Abou-Jaoude ◽  
Blanca E. Carbia ◽  
Caryn Plummer ◽  
Anuj Chauhan

Macromol ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 1-19
Author(s):  
Amol Batra ◽  
Fengyuan Yang ◽  
Michael Kogan ◽  
Anthony Sosnowik ◽  
Courtney Usher ◽  
...  

High-molecular-weight hypromellose (HPMC) and hydroxypropyl cellulose (HPC) are widely known, extended-release polymers. Conventional high-molecular-weight HPMCs are preferred in extended-release applications but not widely used in twin-screw melt granulation due to processability difficulties at low operating temperatures and potential drug degradation if high processing temperatures are used. Conversely, high-molecular-weight grade HPC (Klucel®) can be used in melt granulation processes. The purpose of this study was to evaluate the processability and dissolution behavior of HPC GXF ((Klucel® GXF) and a recently introduced type of hot-melt extrudable HPMC (Affinisol®) in extended-release metformin hydrochloride formulations using twin-screw melt granulation. Powder blends were prepared with 75% w/w metformin HCl and 25% w/w polymeric binder. Blends were granulated at processing temperatures of 160, 140, 120 and 100 °C. HPMC HME 4M (Affinisol® 4M) provided a fine powder, indicating minimum granulation at processing temperatures lower than 160 °C, and the tablets obtained with these granules capped during tableting. In contrast, acceptable tablets could be obtained with HPC GXF at all processing temperatures. Rheological studies including capillary rheometry to measure steady shear rate viscosity, and rotational rheometry to obtain time and temperature superposition data, showed that HPC GXF had a greater thermoplasticity than HPMC HME 4M, which made granulation possible with HPC GXF at low temperatures. Tablets compressed with granules obtained at 160 °C with both binders showed comparable dissolution profiles. High-molecular-weight HPC GXF provided a better processability at low temperatures and adequate tablet strength for the melt granulation of metformin HCl.


2020 ◽  
Vol 28 (9) ◽  
pp. 3031-3039 ◽  
Author(s):  
Mark Phillips ◽  
Christopher Vannabouathong ◽  
Tahira Devji ◽  
Rahil Patel ◽  
Zoya Gomes ◽  
...  

Abstract Purpose There are a number of developments in intra-articular therapies that have been determined to be differentiating factors within the classes of treatments. This study evaluated the efficacy and safety of intra-articular treatments of primary knee osteoarthritis in the short term (3 months follow-up), using a network meta-analysis design, while taking within-class differentiating factors into consideration. Methods A literature search of MEDLINE (through OVID), EMBASE (through OVID), Cochrane Central Register of Controlled Trials for all trials comparing intra-articular therapies was conducted on November 12, 2018. The treatments assessed were high molecular weight and low molecular weight hyaluronic acid injections, extended-release corticosteroids, standard-release corticosteroids, platelet-rich plasma, and saline. A frequentist network meta-analysis was conducted for each outcome. Results Sixty-four articles (9710 patients) met the inclusion criteria. High molecular weight hyaluronic acid (− 0.53, 95% CI − 0.81 to − 0.25) and PRP (− 0.79, 95% CI − 1.32 to − 0.26) were the only treatments with a confidence interval that lay completely above the MID threshold; however, PRP results varied within sensitivity analyses. For the function analysis, high molecular weight hyaluronic acid (SMD − 0.76, 95% CI − 1.30 to − 0.22) was the only treatment with a confidence interval entirely above the MID. Extended-release corticosteroid demonstrated a possible benefit in functional improvement (SMD − 0.98, 95% CI − 1.79 to − 0.17) compared to that of standard-release corticosteroid (SMD − 0.14, 95% CI − 0.72 to 0.44). Conclusion High molecular weight HA was the only treatment to surpass the MID for both pain and function outcomes. Extended-release corticosteroids may provide additional clinical benefit over standard-release corticosteroids. Platelet-rich plasma demonstrated possibly beneficial results; however, wide confidence intervals and sensitivity analyses made the conclusions of efficacy uncertain. Level of evidence Level 1. Systematic review of level 1 evidence.


Author(s):  
Richard B. Vallee

Microtubules are involved in a number of forms of intracellular motility, including mitosis and bidirectional organelle transport. Purified microtubules from brain and other sources contain tubulin and a diversity of microtubule associated proteins (MAPs). Some of the high molecular weight MAPs - MAP 1A, 1B, 2A, and 2B - are long, fibrous molecules that serve as structural components of the cytamatrix. Three MAPs have recently been identified that show microtubule activated ATPase activity and produce force in association with microtubules. These proteins - kinesin, cytoplasmic dynein, and dynamin - are referred to as cytoplasmic motors. The latter two will be the subject of this talk.Cytoplasmic dynein was first identified as one of the high molecular weight brain MAPs, MAP 1C. It was determined to be structurally equivalent to ciliary and flagellar dynein, and to produce force toward the minus ends of microtubules, opposite to kinesin.


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