A long acting biodegradable controlled delivery of chitosan microspheres loaded with tetanus toxoide as model antigen

The chitosan microspheres formulated by emulsion cross-linking method were found to be smooth and spherical without aggregation. The particle size range was between 1 and 90 μm. The particle sizes were found to be influenced by the concentration of the chitosan gel. Tetanus toxoide (TT) vaccine was loaded by passive adsorption from an aqueous solution into the preformed chitosan microspheres cross-linked with glutaraldehyde. The loaded TT on to microspheres was estimated by ELISA method. The loading capacity was found to be 40% with microspheres prepared with 1% chitosan gel, 43% for 2% and 46% for the mixed batch of microspheres prepared from 1% and 2% chitosan gel. The loading efficiency was found to decrease with increase in the concentration of chitosan gel. The in vitro release of the antigenic TT into the phosphate buffer at 37 °C from different batch of microspheres was studied and release had a remarkable dependence on the size of micropsheres. The percentage release of TT from chitosan microspheres prepared from 1% chitosan gel was 2.7% in 120 days and that from 2% chitosan gel was only 2%. The mixed batch of microspheres could release 2.3% in 120 days. The antigen integrity was investigated by SDS–PAGE with brilliant blue staining. The SDS–PAGE analysis confirmed that the antigen integrity was not affected by passive adsorption of protein antigen to preformed chitosan microspheres. The study revealed that the cross-linked chitosan microspheres would be an interesting system for long-term delivery of macromolecules drugs.     

Lenalidomide: the emerging role of a novel targeted agent in malignancies

Lenalidomide is an immunomodulatory drug that was developed by modification of the first-generation immunomodulatory drug thalidomide in a drug discovery program. Lenalidomide more potently regulates cellular immune and cytokine responses, while lacking the side-effect profile of thalidomide. The promising activity seen in multiple myeloma and myelodysplastic syndrome has led to its approval by the U.S. Food and Drug Administration in these conditions. The clinical results that we have seen so far, which demonstrate significant efficacy with a tolerable toxicity profile, provide a strong basis for the use of lenalidomide in other malignancies. Combination therapy with lenalidomide could enhance this agent's antineoplastic role; this is likely the position it will occupy in the armamentarium against cancer.     

Diagnostic accuracy of noninvasive coronary angiography with 320-detector row computed tomography

We sought to evaluate the diagnostic accuracy of noninvasive coronary angiography using 320-detector row computed tomography, which provides 16-cm craniocaudal coverage in 350 ms and can image the entire coronary tree in a single heartbeat, representing a significant advance from previous-generation scanners. We evaluated 63 consecutive patients who underwent 320-detector row computed tomography and invasive coronary angiography for the investigation of suspected coronary artery disease. Patients with known coronary artery disease were excluded. Computed tomographic (CT) studies were assessed by 2 independent observers blinded to results of invasive coronary angiography. A single observer unaware of CT results assessed invasive coronary angiographic images quantitatively. All available coronary segments were included in the analysis, regardless of size or image quality. Lesions with >50% diameter stenoses were considered significant. Mean heart rate was 63 ± 7 beats/min, with 6 patients (10%) in atrial fibrillation during image acquisition. Thirty-three patients (52%) and 70 of 973 segments (7%) had significant coronary stenoses on invasive coronary angiogram. Seventeen segments (2%) were nondiagnostic on computed tomogram and were assumed to contain significant stenoses on an "intention-to-diagnose" analysis. Sensitivity, specificity, and positive and negative predictive values of computed tomography for detecting significant stenoses were 94%, 87%, 88%, and 93%, respectively, by patient (n = 63), 89%, 95%, 82%, and 97%, respectively, by artery (n = 260), and 87%, 97%, 73%, and 99%, respectively, by segment (n = 973). In conclusion, noninvasive 320-detector row CT coronary angiography provides high diagnostic accuracy across all coronary segments, regardless of size, cardiac rhythm, or image quality.