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- Comprehensive review on full bone regeneration through 3D printing approachesPublication . Fernandes, Cristiana; Moura, Carla; Ascenso, Rita M.T.; Amado, Sandra; Alves, Nuno; Pascoal-Faria, PaulaOver the last decades, the number of work accidents associated with bone fractures has increased leading to a growing concern worldwide. Currently, autografts, allografts, and xenografts are used for bone regeneration. However, their application has associated risks. Tissue engineering (TE) has brought solutions to address these problems, through the production of temporary supports, providing mechanical support to the formation of new bone tissue and biocompatible and biodegradable scaffolds, which allow cell adhesion and proliferation to ensure bone formation. The combination of materials and structure with the technique to be used will directly influence their physical and chemical properties and, consequently, their action in contributing to bone regeneration. Thus, the focus of this chapter is to perform an exhaustive literature review and a critical analysis of the state of the art in bone TE and present a proposal of an optimized temporary support geometry for bone regeneration in case of large bone defects. For this, it was listed and identified the best choice of biomaterials, fabrication method, cell type and their culture conditions (static vs. dynamic), and/or the inclusion of growth factors for the repair of large bone defects.
- Sheep Gait Biomechanics and the Assessment of Musculoskeletal Conditions: A Systematic ReviewPublication . Silva, Rui; Dimas, Ivo Santos; Fernandez, Justin W.; Alves, Nuno; Morouço, Pedro; Maurício, Ana Colette; Veloso, António; Sandra, AmadoIn recent years, sheep have been reported as the ideal animal model to study osteoporosis, hence it is important to identify instruments, tools and ideal parameters needed to assess the effects of different treatments. In previous studies conducted in other animal models with osteoporosis, the most common parameters used for evaluation concerned primarily bone properties, such as the dual X-ray absorptiometry. However, biomechanical gait analysis as an integrative functional parameter and a non-invasive method, will be an important tool in research and clinical applications. This research review was performed using the PubMed database and included studies related to sheep with outcome measures concerning functional performance assessed during gait in vivo; and excluded studies related with cardiovascular disease and sperm properties, which include other animal species, with outcomes not related with functional locomotor evaluation. Only studies related with bone properties were analyzed. The most frequent and relevant included parameters were the following: mean peak vertical ground force reaction, gait cycle and stance/swing phase duration, percentage of stance/swing phase in a gait cycle, stride length and the stifle joint angles during a gait cycle. Gait biomechanical parameters have been established for the assessment of some clinical orthopedic condition using sheep models but not currently for osteoporosis.
- 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.
- Anastomotic Leak in Colorectal Cancer Surgery: From Diagnosis to Management or Failure - A Retrospective Cohort StudyPublication . Rama, Nuno; Parente, Diana; Silva, Cândida G.; Neves, Miguel; Figueiredo, Nuno; Alves, Paulo; Amado, Sandra; Lourenço, Óscar; Guarino, Maria Pedro; Rocha, Anabela; Castro-Poças, Fernando; Pimentel, JoãoAnastomotic leakage (AL) after colorectal resections is a common surgical experience and the most frequent major adverse outcome. Early recognition of AL is critical to reduce mortality. We aim to evaluate the incidence, diagnostic criteria, morbidity, and mortality related with AL.
- 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