An anatomical study of porcine peripheral nerve and its potential use in nerve tissue engineering

yesCurrent nerve tissue engineering applications are adopting xenogeneic nerve tissue as potential nerve grafts to help aid nerve regeneration. However, there is little literature that describes the exact location, anatomy and physiology of these nerves to highlight their potential as a donor graft. The aim of this study was to identify and characterise the structural and extracellular matrix (ECM) components of porcine peripheral nerves in the hind leg. Methods included the dissection of porcine nerves, localisation, characterisation and quantification of the ECM components and identification of nerve cells. Results showed a noticeable variance between porcine and rat nerve (a commonly studied species) in terms of fascicle number. The study also revealed that when porcine peripheral nerves branch, a decrease in fascicle number and size was evident. Porcine ECM and nerve fascicles were found to be predominately comprised of collagen together with glycosaminoglycans, laminin and fibronectin. Immunolabelling for nerve growth factor receptor p75 also revealed the localisation of Schwann cells around and inside the fascicles. In conclusion, it is shown that porcine peripheral nerves possess a microstructure similar to that found in rat, and is not dissimilar to human. This finding could extend to the suggestion that due to the similarities in anatomy to human nerve, porcine nerves may have utility as a nerve graft providing guidance and support to regenerating axons

Robust Online Hamiltonian Learning

In this work we combine two distinct machine learning methodologies, sequential Monte Carlo and Bayesian experimental design, and apply them to the problem of inferring the dynamical parameters of a quantum system. We design the algorithm with practicality in mind by including parameters that control trade-offs between the requirements on computational and experimental resources. The algorithm can be implemented online (during experimental data collection), avoiding the need for storage and post-processing. Most importantly, our algorithm is capable of learning Hamiltonian parameters even when the parameters change from experiment-to-experiment, and also when additional noise processes are present and unknown. The algorithm also numerically estimates the Cramer-Rao lower bound, certifying its own performance.Comment: 24 pages, 12 figures; to appear in New Journal of Physic

UV-Casting on methacrylated PCL for the production of a peripheral nerve implant containing an array of porous aligned microchannels

Peripheral nerves are basic communication structures guiding motor and sensory information from the central nervous system to receptor units. Severed peripheral nerve injuries represent a large clinical problem with relevant challenges to successful synthetic nerve repair scaffolds as substitutes to autologous nerve grafting. Numerous studies reported the use of hollow tubes made of synthetic polymers sutured between severed nerve stumps to promote nerve regeneration while providing protection for external factors, such as scar tissue formation and inflammation. Few approaches have described the potential use of a lumen structure comprised of microchannels or microfibers to provide axon growth avoiding misdirection and fostering proper healing. Here, we report the use of a 3D porous microchannel-based structure made of a photocurable methacrylated polycaprolactone, whose mechanical properties are comparable to native nerves. The neuro-regenerative properties of the polymer were assessed in vitro, prior to the implantation of the 3D porous structure, in a 6-mm rat sciatic nerve gap injury. The manufactured implants were biocompatible and able to be resorbed by the host’s body at a suitable rate, allowing the complete healing of the nerve. The innovative design of the highly porous structure with the axon guiding microchannels, along with the observation of myelinated axons and Schwann cells in the in vivo tests, led to a significant progress towards the standardized use of synthetic 3D multichannel-based structures in peripheral nerve surgery

Unterschiedliche Abheilungsdauer und Häufigkeit der Hospitalisation bei Ulcus cruris verschiedener Ursachen

BACKGROUND: Leg ulcers are a symptom of a heterogeneous group of diseases. Their treatment causes substantial costs due to the long healing times and extensive wound care measures. There is a paucity of information about healing times and the necessity of hospital treatment for leg ulcers of different etiologies. MATERIALS AND METHODS: In this retrospective study, healing times and the frequency of in-hospital treatment of 355 patients with leg ulcers attending a wound care clinic of a university hospital were examined. RESULTS: The proportion of healed ulcers was 32.0 % after 3 months and 54.3 % after 6 months with an average treatment duration of 6.1 months for all ulcers. This proportion of healed ulcers was higher for venous ulcers with 45.5 % after 3 months and 63.0 % after 6 months, whereas only 30.0 % of mixed arterial-venous ulcers and 35.0 % of hypertensive ischemic leg ulcers (HYTILU) were healed after 6 months. Of the latter group, 71 % of patients were hospitalized at least once during the observation period as compared to 47 % of patients with a venous ulcer. The duration of the hospital stay was longer for mixed ulcers and HYTILU with an average of 30 days vs. 23 days for venous ulcers. CONCLUSIONS: These data indicate that the healing times of ulcers of different etiologies differ substantially and that especially ulcers with arteriosclerosis as a causative factor have longer healing times. The fact that they require in-hospital treatment more frequently and for longer periods has significant socio-economic consequences

2023 MASCC and ESMO guideline update for the prevention of chemotherapy- and radiotherapy-induced nausea and vomiting

Nausea and vomiting are still considered to be two of the most troublesome adverse events (AEs) for patients treated with antineoplastic therapy. To optimise the utility of available antiemetic prophylaxis, updated reviews of the relevant literature and evidence-based guideline recommendations are crucial. The European Society for Medical Oncology (ESMO) and the Multinational Association of Supportive Care in Cancer (MASCC) completed the fourth Consensus Conference on Antiemetics for the prevention of nausea and vomiting in patients with cancer in Copenhagen in June 2015. This article is an update of the 2015 guidelines.Meeting and production costs have been covered by MASCC and ESMO from central funds.https://www.esmoopen.comhj2024ImmunologySDG-03:Good heatlh and well-bein

Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications

BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (VT) size was 500 ml, or 7 to 9 ml kg1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P < 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P < 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high VT and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome

Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications: LAS VEGAS - An observational study in 29 countries

BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (V T) size was 500 ml, or 7 to 9 ml kg−1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P ˂ 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P ˂ 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high V T and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome.</p

EB curing and cure grafting of novel CT monomer complexes : comparison with UV process and extention of the technique to thiol-ene systems

EB curing and cure grafting of charge transfer (CT) monomer complexes is discussed. The complexes studied involve representative donors (D) such as vinyl ethers and typical acceptors (A) including maleates, maleimides and acrylates also oligomers. The EB results are compared with UV curing and cure grafting of the same complexes. The work has been extended to include EB/UV curing and cure grafting of thiol-ene systems. The significance of these results in the potential commercial application of these complexes is discussed

Cure grafting - a complementary technique to preirradiation and simultaneous processes?

A novel radiation grafting process, termed cure grafting, based on curing of donor/acceptor (DA) monomers as charge transfer complexes initiated by UV or any ionising radiation source, is proposed. The system is complementary to the existing preirradiation and simultaneous radiation grafting methods. The advantages and disadvantages of cure grafting are summarised. Examples of cure grafting using representative DA monomers are described with cellulose as model substrate in the presence of UV or EB. A unique property of cure grafting is that the yield is known quantitatively prior to irradiation