18 research outputs found
Preparation of Active Proteins, Vaccines and Pharmaceuticals as Fine Powders using Supercritical or Near-Critical Fluids
Supercritical or near-critical fluid processes for generating microparticles have enjoyed considerable attention in the past decade or so, with good success for substances soluble in supercritical fluids or organic solvents. In this review, we survey their application to the production of protein particles. A recently developed process known as CO2-assisted nebulization with a Bubble Dryer® (CAN-BD) has been demonstrated to have broad applicability to small-molecule as well as macromolecule substances (including therapeutic proteins). The principles of CAN-BD are discussed as well as the stabilization, micronization and drying of a wide variety of materials. More detailed case studies are presented for three proteins, two of which are of therapeutic interest: anti-CD4 antibody (rheumatoid arthritis), α1-antitrypsin (cystic fibrosis and emphysema), and trypsinogen (a model enzyme). Dry powders were formed in which stability and activity are maintained and which are fine enough to be inhaled and reach the deep lung. Enhancement of apparent activity after CAN-BD processing was also observed in some formulation and processing conditions
Affecting the Ageing Behaviour of Injection-Moulded Microparts Using Variothermal Mould Tempering
The fast cooling of the melt in an injection moulding process for manufacturing polymer microparts can lead to a modified inner structure, resulting in minor mechanical properties. Furthermore, the ageing can be also dependent on the process-induced properties. The results indicate that especially physical ageing processes occur in parts with unpropitious inner properties. Chemical ageing processes seem to occur independently of the process conditions in microparts. Tensile tests indicate that a process-induced favoured morphology can reduce the ageing-based change of mechanical properties
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Effects of chlorogenic acid and bovine serum albumin on the oxidative stability of low density lipoproteins in vitro
The ability of chlorogenic acid to inhibit oxidation of human low-density lipoprotein (LDL) was studied by in vitro copper-induced LDL oxidation. The effect of chlorogenic acid on the lag time before LDL oxidation increased in a dose dependent manner by up to 176% of the control value when added at concentrations of 0.25 -1.0 μM. Dose dependent increases in lag time of LDL oxidation were also observed, but at much higher concentrations, when chlorogenic acid was incubated with LDL (up to 29.7% increase in lag phase for 10 μM chlorogenic acid) or plasma (up to 16.6% increase in lag phase for 200 μM chlorogenic acid) prior to isolation of LDL, and this indicated that chlorogenic acid was able to bind, at least weakly, to LDL. Bovine serum albumin (BSA) increased the oxidative stability of LDL in the presence of chlorogenic acid. Fluorescence spectroscopy showed that chlorogenic acid binds to BSA with a binding constant of 3.88 x 104 M-1. BSA increased the antioxidant effect of chlorogenic acid, and this was attributed to copper ions binding to BSA, thereby reducing the amount of copper available for inducing lipid peroxidation
Quality of life after pertrochanteric femoral fractures treated with a gamma nail: a single center study of 62 patients
<p>Abstract</p> <p>Background</p> <p>Intramedullary nailing of pertrochanteric femoral fractures has grown in popularity over the past 2 decades likely because this procedure is associated with a low risk for postoperative morbidity and a fast recovery of function. The evaluation of outcomes associated with pertrochanteric nailing has mainly been based on objective measures. The purpose of the present study is to correlate patients’ health-related quality of life results after intramedullary nailing of pertrochanteric fractures with objective outcome measures.</p> <p>Methods</p> <p>We conducted a single-center study including 62 patients (mean age 80 ± 10 years) with pertrochanteric fractures treated with a Gamma 3 Nail. Health related quality of life was measured using the Short Form-36. These results were compared to both US and Austrian age and sex-adjusted population norms. The objective outcome measures studied at one year postoperatively included Harris Hip Score, range of motion, leg length, body mass index, neck-shaft angle and grade of osteoarthritis.</p> <p>Results</p> <p>According to the Harris Hip Score 43 patients (67%) had excellent or good results. There was no significant difference in the average neck-shaft angle comparing affected hip to non-affected hip at 12 months postoperatively. The average osteoarthritis score, for both the injured and uninjured hip, did not differ significantly. We found significant differences between the bodily pain, social functioning and mental health subscales and two summary scores of the Short-Form 36 in comparison to Austrian population norms. Complication rate was 8%.</p> <p>Conclusions</p> <p>The results of this study confirm that intramedullary nailing with the use of a Gamma Nail is a safe treatment option for stable and unstable pertrochanteric fractures. Despite good functional and radiographic results we noticed a substantial fall off in patients’ quality of life up to 12 months after operation.</p