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- Tailoring Bioengineered Scaffolds for Regenerative MedicinePublication . Amado, Sandra; Morouço, Pedro; Pascoal-Faria, Paula; Alves, NunoThe vision to unravel and develop biological healing mechanisms based on evolving molecular and cellular technologies has led to a worldwide scientific endeavor to establish regenerative medicine. This is a multidisciplinary field that involves basic and preclinical research and development on the repair, replacement, and regrowth or regeneration of cells, tissues, or organs in both diseases (congenital or acquired) and traumas. A total of over 63,000 patients were officially placed on organs’ waiting lists on 31 December 2013 in the European Union (European Commission, 2014). Tissue engineering and regen erative medicine have emerged as promising fields to achieve proper solutions for these concerns. However, we are far from having patient-specific tissue engineering scaffolds that mimic the native tissue regarding both structure and function. The proposed chapter is a qualitative review over the biomaterials, processes, and scaffold designs for tailored bioprinting. Relevant literature on bioengineered scaffolds for regenerative medicine will be updated. It is well known that mechanical properties play significant effects on bio logic behavior which highlight the importance of an extensively discussion on tailoring biomechanical properties for bioengineered scaffolds. The following topics will be dis cussed: scaffold design, biomaterials and scaffolds bioactivity, biofabrication processes, scaffolds biodegradability, and cell viability. Moreover, new insights will be pointed out.
- Intracorporeal versus extracorporeal anastomosis in laparoscopic right colectomy: short-term outcomesPublication . Gil, Inês Campos; Rama, Nuno; Parente, Diana; Sales, Inês; Alves, Paulo; Clara, Paulo; Amado, Sandra; Coelho, Miguel; Faria, VítorBackground: Recently, there has been a growing enthusiasm in developing new techniques of intracorporeal anastomosis following laparoscopic colectomy, which are more challenging than extracorporeal techniques. However, the evidence is still lacking regarding the outcomes’ comparison of both procedures. Methods: We designed a retrospective study comparing intracorporeal and extracorporeal anastomosis following laparoscopic right colectomy. A total of 115 consecutive patients operated for right colon disease were identified, from September 1st 2014 to May 31st 2017. Patient demographics included age, gender, ASA score, past abdominal surgery, anticoagulant and steroid therapy, Diabetes Mellitus and preoperative diagnosis. The analysed outcomes included length of stay, operative time, blood loss, extraction site, postoperative complications (ileus, anastomotic failure and surgical site infection), reoperation rate, readmission rate and 30-day mortality. Results: The extracorporeal group included 84 and the intracorporeal group 31 patients. The intracorporeal group had less surgical site infections (3,2% versus 27,4%, p<0,05). There were no statistically significant differences in operative time, blood loss, ileus, anastomotic failure or mortality. Conclusion: Our study reveals similar outcomes for both intra- and extracorporeal anastomosis following laparoscopic right colectomy. Therefore, intracorporeal anastomosis seems to be a feasible and safe technique in the hands of experienced laparoscopic colorectal surgeons.
- Electrical Stimulation Optimization in Bioreactors for Tissue Engineering ApplicationsPublication . Pascoal-Faria, Paula; Ferreira, Pedro Castelo; Datta, Abhishek; Amado, Sandra; Moura, Carla; Alves, NunoWe review here the current research status on bioreactors for tissue engineering with cell electrical stimulation. Depending on the cell types, electrical stimulation has distinct objectives: 1) being employed both to mimic and enhance endogenous electricity measured in the natural regeneration of living organisms and 2) to mimic strain working conditions for contractible tissues (for instance muscle and cardiac tissues). Understanding the distinct parameters involved in electrical stimulation is crucial to optimize its application. The results presented in the literature and reviewed here reveal that the application of electrical stimulation can be essential for tissue engineering applications.
- A multimodal stimulation cell culture bioreactor for tissue engineering: A numerical modelling approachPublication . Meneses, João; Silva, João C.; Fernandes, Sofia R.; Datta, Abhishek; Ferreira, Frederico Castelo; Moura, Carla; Amado, Sandra; Alves, Nuno; Pascoal-Faria, PaulaThe use of digital twins in tissue engineering (TE) applications is of paramount importance to reduce the number of in vitro and in vivo tests. To pursue this aim, a novel multimodal bioreactor is developed, combining 3D design with numerical stimulation. This approach will facilitate the reproducibility between studies and the platforms optimisation (physical and digital) to enhance TE. The new bioreactor was specifically designed to be additive manufactured, which could not be reproduced with conventional techniques. Specifically, the design suggested allows the application of dual stimulation (electrical and mechanical) of a scaffold cell culture. For the selection of the most appropriate material for bioreactor manufacturing several materials were assessed for their cytotoxicity. Numerical modelling methods were then applied to the new bioreactor using one of the most appropriate material (Polyethylene Terephthalate Glycol-modified (PETG)) to find the optimal stimulation input parameters for bone TE based on two reported in vitro studies.
- Apoiar no autocuidado de utentes e cuidadores informaisPublication . Dixe, Maria dos Anjos; Querido, Ana; Soares, Elsa; Gomes, José Carlos; Pereira, Cidália; Teixeira, Liliana; Sousa, Pedro; Amado, Sandra; Peralta, Teresa
- Combined Use of Chitosan and Olfactory Mucosa Mesenchymal Stem/Stromal Cells to Promote Peripheral Nerve Regeneration In VivoPublication . Alvites, R. D.; Branquinho, Mariana V.; Sousa, Ana C.; Amorim, Irina; Magalhães, Rui; João, Filipa; Almeida, Diogo; Amado, Sandra; Prada, Justina; Pires, Isabel; Zen, Federica; Raimondo, Stefania; Luís, Ana L.; Geuna, Stefano; Varejão, Artur S. P.; Maurício, Ana C.Peripheral nerve injury remains a clinical challenge with severe physiological and functional consequences. Despite the existence of multiple possible therapeutic approaches, until now, there is no consensus regarding the advantages of each option or the best methodology in promoting nerve regeneration. Regenerative medicine is a promise to overcome this medical limitation, and in this work, chitosan nerve guide conduits and olfactory mucosa mesenchymal stem/stromal cells were applied in different therapeutic combinations to promote regeneration in sciatic nerves after neurotmesis injury. Over 20 weeks, the intervened animals were subjected to a regular functional assessment (determination of motor performance, nociception, and sciatic indexes), and after this period, they were evaluated kinematically and the sciatic nerves and cranial tibial muscles were evaluated stereologically and histomorphometrically, respectively. The results obtained allowed confirming the beneficial effects of using these therapeutic approaches. The use of chitosan NGCs and cells resulted in better motor performance, better sciatic indexes, and lower gait dysfunction after 20 weeks. The use of only NGGs demonstrated better nociceptive recoveries. The stereological evaluation of the sciatic nerve revealed identical values in the different parameters for all therapeutic groups. In the muscle histomorphometric evaluation, the groups treated with NGCs and cells showed results close to those of the group that received traditional sutures, the one with the best final values. The therapeutic combinations studied show promising outcomes and should be the target of new future works to overcome some irregularities found in the results and establish the combination of nerve guidance conduits and olfactory mucosa mesenchymal stem/stromal cells as viable options in the treatment of peripheral nerves after injury.
- Biomechanical Outcomes Related with Gait in Children with Cerebral Palsy Using Ankle-Foot Orthotic - A Systematic ReviewPublication . Gordo, Jessica Jorge; Pascoal-Faria, Paula; Mateus, Artur; Morouço, Pedro; Schiriati, Verónica; Sandra, AmadoGait in children with cerebral palsy (CP) is often affected by motor impairments which limit the patient's ability to walk. To improve gait and reduce walking limitations, children with CP need to use ankle foot orthoses. An orthosis is an externally applied device that is designed and fitted to the body to achieve one or more of the following goals: a) Control biomechanical alignment. b) Correct or accommodate deformity, and 3) Protect and support an injury. This systematic review aims to describe research evidence supporting the use of ankle-foot orthoses to improve gait biomechanical outcomes among individuals with CP. Literature search was pursued from PubMed database. Studies were included if (1) they evaluated an outcome measure related with gait using ankle-foot orthotic (AFO) in children (2) considered children with a diagnosis of CP and have a (3) GMFCS classification of I, II or III. Papers were excluded if they evaluated (1) other population besides CP, (2) the use of orthoses other than AFOs and (3) gait analysis procedure was not presented. All the included studies have analyzed spatiotemporal parameters, the step length (m), stride length (m) and cadence (steps/minute) were the most frequently reported. Our findings showed that several studies have investigated the effects of AFOs, all of which have reported positive influences on at least one gait parameter, as well as positive changes in joint kinematics and kinetic in children with CP.
- Implementation of the International Classification of Functioning, Disability, and Health (ICF) Core Sets for Children and Youth with Cerebral Palsy: Global Initiatives Promoting Optimal FunctioningPublication . Schiariti, Verónica; Longo, Egmar; Shoshmin, Alexander; Kozhushko, Ludmila; Besstrashnova, Yanina; Król, Maria; Campos, Taynah Neri Correia; Ferreira, Haryelle Náryma Confessor; Verissimo, Cláudia; Shaba, Daniel; Mwale, Matilda; Amado, SandraBackground: The International Classification of Functioning, Disability, and Health (ICF) Core Sets for children and youth with cerebral palsy (CP) offer service providers and stakeholders a specific framework to explore functioning and disability for assessment, treatment, evaluation, and policy purposes in a global context. Objective: Describe global initiatives applying the ICF Core Sets for children and youth with CP, with a focus on contributions to clinical practice and challenges in their implementation. Methods: This is a descriptive cross-sectional study. Ongoing initiatives applying the ICF Core Sets for CP in Russia, Poland, Malawi, and Brazil are included. Results: The main contributions of applying the ICF Core Sets for children and youth with CP include: (1) an objective description of abilities and limitations in everyday activities; (2) a consistent identification of facilitators and barriers influencing functioning; (3) a practical communication tool promoting client-centered care and multidisciplinary teamwork; and, (4) a useful guideline for measurement selection. The main challenges of adopting the ICF Core Sets are related to lack of ICF knowledge requiring intense training and translating results from standardized measures into the ICF qualifiers in a consistent way. Conclusions: Global initiatives include research and clinical applications at the program, service and system levels. The ICF Core Sets for CP are useful tools to guide service provision and build profiles of functioning and disability. Global interprofessional collaboration, capacity training, and informatics (e-records) will maximize their applications and accelerate adoption.
- Protein Nanocarriers for Targeted Drug Delivery for Cancer TherapyPublication . Kariduraganavar, Mahadevappa Y.; Heggannavar, Geetha B.; Amado, Sandra; Mitchell, Geoffrey R.This chapter describes how proteins can be used to provide effective targeted nanocarriers for drugs to target tumors. This approach offers an exciting framework for cancer therapies in the future, allowing multiple therapeutic agents and other functions to be combined in the same particle and ensuring a lower toxicity for the patient. The use of proteins provides a rich library of functional molecules to exploit in this methodology. The role of computer simulation to identify the best combination of protein, ligand, and drugs is highlighted.
- A Computer Tool for 3D Shape Recovery of FruitsPublication . Gaspar, Miguel; Pascoal-Faria, Paula; Amado, Sandra; Alves, NunoCharacterizing a fruit’s mechanical behavior is an important step towards reducing economic losses due to bruising. Several 3D scanning technologies allow to obtain the external geometry of a fruit, but no easily accessible tools exist for the acquisition of the geometry of internal structures such as the core. We propose a low-cost destructive method for tomographic reconstruction of a fruit from scanned slices. A method for overcoming the difficulties in registering the different images is also presented.