Cationised dextran and pullulan modified with diethyl aminoethyl methacrylate for gene delivery in cancer cells.

This work describes the synthesis and characterisation of cationised dextran and pullulan modified with diethyl aminoethyl methacrylate (DEAEM) for gene delivery in cancer cells. To dextran and pullulan, PEI was conjugated to impart cationicity. These cationised polysaccharides were then modified with DEAEM monomer via Michael addition reaction and synthesised four different derivatives viz DPD I, DPD II, PPD I and PPD II. These vectors form nanocomplexes with DNA exhibiting positive zeta potential. These nanoplexes are cytocompatible in C6, HeLa and L929 cells. Transfection efficiency of these vectors was evaluated using p53 plasmid which demonstrated good transfection in cancer cells (C6 and HeLa) alone. Biodistribution studies of DPD II and PPD II in BALB/c mice shows its tendency to accumulate in liver tissue and not in any vital organs like brain, lungs and heart. In addition, these derivatives also exhibit good renal clearance.

A novel technique to develop thoracic spinal laminectomy and a methodology to assess the functionality and welfare of the contusion spinal cord injury (SCI) rat model.

This study reports the advantage of a novel technique employing a motorised dental burr to assist laminectomy over the conventional manual technique at T10-T11 vertebra level in a rat model of spinal cord injury. Twenty-four female rats were randomly assigned to four groups: (1) conventionally laminectomised, (2) dental burr assisted laminectomised, (3) conventionally laminectomised with spinal cord contusion and (4) dental burr assisted laminectomised with spinal cord contusion. Basso Beattie Bresnahan (BBB) score, postoperative body weights, rat grimace scale (RGS), open cage activity and rearing was studied at 1, 7, 14, 21 and 28 days postoperatively, and area of spinal tissue affected was evaluated histologically. Laminectomised and spinal cord injured rats from dental burr groups showed significantly more weight gain and less weight loss respectively in comparison with respective conventionally laminectomised groups at various time points. Significantly higher RGS score was noticed in conventionally laminectomised animals on Day 1 in comparison to burr assisted laminectomy and presence of pain was evident until Day 7 in the conventionally spinal cord injured group. BBB score did not differ between techniques, whereas laminectomy groups showed more resting time than spinal injury groups. High rearing score was significantly higher in groups which underwent dental burr assisted technique at various time points with respect to their conventional counterparts. This study suggests that the use of dental burr assisted technique to perform laminectomy will bring refinement by producing less pain, aiding in better recovery, removing procedural artefacts without affecting the outcome of the model.