Exogenous hyaluronidase induces release of nitric oxide from the coronary endothelium

Nitrous Oxide Improves Tissue Perfusion in Vascular Occlusion Management

Filler-related vascular occlusion (VO) treatment remains challenging despite established protocols, including high-dose pulsed hyaluronidase injections and ultrasound-guided targeted injections. Managing patients' pain and anxiety during treatment presents additional difficulties. Nitrous oxide (N₂O) has been found to be effective for analgesia and anxiolysis in minor procedures, with a 55% reduction in photodynamic therapy pain, and a visual analog scale reduction from 6.6 to 2.9 for aesthetic laser treatment pain. Use of N₂O for analgesia, anxiolysis, or improvement of perfusion in VO has not been previously reported. We present two cases of filler-related VO management with high-dose hourly hyaluronidase injections and adjunctive use of self-administered 50% N₂O. Pain and anxiety of the treatment were self-reported by the patients. Capillary refill and livedo reticularis were monitored for establishing VO diagnosis and treatment outcome. In both cases, self-administration of N₂O led to contemporaneous improvement in skin perfusion. Patients reported decreased anxiety and pain during treatment. Hyaluronidase treatment led to permanent resolution of occlusion symptoms. N₂O presents a promising adjunctive treatment option for relief of pain and anxiety, and potentially additional perfusion improvement. Further investigation is necessary to better define N₂O's role in treating VO.

Safety and efficacy of addition of hyaluronidase to a mixture of lidocaine and bupivacaine in scalp nerves block in elective craniotomy operations; comparative study

BACKGROUND

Patients undergoing craniotomy operations are prone to various noxious stimuli, many strategies are commenced to provide state of analgesia, for better control of the stress response and to overcome its undesired effects on the haemodynamics and post-operative pain. Scalp nerves block are considered one of these strategies. This study was conceived to evaluate the effect of addition of hyaluronidase to the local anaesthetic mixture used in the scalp nerves block in patients undergoing elective craniotomy operations.

METHODS

64 patients undergoing elective craniotomy operations were enrolled in this prospective randomized, double-blind comparative study. Patients were randomly assigned to two groups. Group LA, patients subjected to scalp nerves block with 15 ml bupivacaine 0.5%, 15 ml lidocaine 2%, in 1:400000 epinephrine. Group H as Group LA with15 IU /ml Hyaluronidase.

RESULTS

Patients in the H group showed lower VAS values for 8 h postoperative, compared to the LA group. The haemodynamic response showed lower values in the H group, compared to the LA group. Those effects were shown in the intraoperative period and for 6 h post-operative. No difference was detected regarding the incidence of complications nor the safety profile.

CONCLUSION

Our data supports the idea that addition of hyaluronidase to the local anesthetic mixture improves the success rates of the scalp nerves block and its efficacy especially during stressful intraoperative periods and in the early postoperative period. No evident undesirable effects in relation to the addition of hyaluronidase.

TRIAL REGISTRATION

Clinical Trial registry on ClinicalTrials.gov , NCT 03411330 , 25-1-2018.

Formulations for DNA delivery via electroporation in vivo

The importance of DNA formulation in safe and efficient electrogene transfer is increasingly recognized as electroporation technology enters into clinical development. A phenomenal increase in naked DNA delivery by electroporation offers new opportunities for nonviral gene therapies previously considered difficult because of insufficient delivery. However, significant tissue damage related to harsh electroporation conditions raises serious safety concerns with the use of electroporation in healthy tissues, which limits its current applications to only nonhealthy tissues such as tumors. DNA formulations designed to minimize tissue damage or enhance expression at weaker electric pulses have been examined to address these concerns. These include formulations fortified with the addition of transfection reagent(s), membrane-permeating agents, tissue matrix modifiers, targeted ligands, or agents modifying electrical conductivity or membrane stability to enhance delivery efficiency or reduce tissue damage. These advancements in DNA formulation could prove to be useful in improving the safety of electroporation protocols for human applications.

Optimisation of electrotransfer of plasmid into skeletal muscle by pretreatment with hyaluronidase -- increased expression with reduced muscle damage

The efficiency of plasmid gene transfer to skeletal muscle can be significantly improved by the application of an electrical field to the muscle following injection of plasmid DNA. However, this electrotransfer is associated with significant muscle damage which may result in substantial loss of transfected muscle fibres. Reduction of the voltage used in the technique can result in a decrease in muscle damage, with a concomitant reduction in expression, but without a significant decrease in the number of transfected fibres. Pre-treatment of the muscle with a solution of bovine hyaluronidase greatly increases the efficiency of plasmid gene transfer when used in conjunction with electrotransfer, but not when used alone. This combination treatment results in greatly enhanced levels of transfected muscle fibres without the increases in muscle damage associated with the electrotransfer process.