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1.
Sensors (Basel) ; 24(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38474907

RESUMO

When a limb suffers a fracture, rupture, or dislocation, it is traditionally immobilized with plaster. This may induce discomfort in the patient, as well as excessive itching and sweating, which creates the growth of bacteria, leading to an unhygienic environment and difficulty in keeping the injury clean during treatment. Furthermore, if the plaster remains for a long period, it may cause lesions in the joints and ligaments. To overcome all of these disadvantages, orthoses have emerged as important medical devices to help patients in rehabilitation, as well as for self-care of deficiencies in clinics and daily life. Traditionally, these devices are produced manually, which is a time-consuming and error-prone method. From another point of view, it is possible to use imageology (X-ray or computed tomography) to scan the human body; a process that may help orthoses manufacturing but which induces radiation to the patient. To overcome this great disadvantage, several types of 3D scanners, without any kind of radiation, have emerged. This article describes the use of various types of scanners capable of digitizing the human body to produce custom orthoses. Studies have shown that photogrammetry is the most used and most suitable 3D scanner for the acquisition of the human body in 3D. With this evolution of technology, it is possible to decrease the scanning time and it will be possible to introduce this technology into clinical environment.


Assuntos
Fraturas Ósseas , Aparelhos Ortopédicos , Humanos , Tomografia Computadorizada por Raios X , Tecnologia , Extremidades
2.
Nanomaterials (Basel) ; 13(24)2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38133059

RESUMO

The increasing use of molybdenum disulfide (MoS2) nanoparticles (NPs) raises concerns regarding their accumulation in soil ecosystems, with limited studies on their impact on soil organisms. Study aim: To unravel the effects of MoS2 nanosheets (two-dimensional (2D) MoS2 NPs) and bulk MoS2 (156, 313, 625, 1250, 2500 mg/kg) on Enchytraeus crypticus and Folsomia candida. The organisms' survival and avoidance behavior remained unaffected by both forms, while reproduction and DNA integrity were impacted. For E. crypticus, the individual endpoint reproduction was more sensitive, increasing at lower concentrations of bulk MoS2 and decreasing at higher ones and at 625 mg/kg of 2D MoS2 NPs. For F. candida, the molecular endpoint DNA integrity was more impacted: 2500 mg/kg of bulk MoS2 induced DNA damage after 2 days, with all concentrations inducing damage by day 7. 2D MoS2 NPs induced DNA damage at 156 and 2500 mg/kg after 2 days, and at 1250 and 2500 mg/kg after 7 days. Despite affecting the same endpoints, bulk MoS2 induced more effects than 2D MoS2 NPs. Indeed, 2D MoS2 NPs only inhibited E. crypticus reproduction at 625 mg/kg and induced fewer (F. candida) or no effects (E. crypticus) on DNA integrity. This study highlights the different responses of terrestrial organisms to 2D MoS2 NPs versus bulk MoS2, reinforcing the importance of risk assessment when considering both forms.

3.
Adv Healthc Mater ; 12(26): e2300828, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37312636

RESUMO

Neural tissue-related illnesses have a high incidence and prevalence in society. Despite intensive research efforts to enhance the regeneration of neural cells into functional tissue, effective treatments are still unavailable. Here, a novel therapeutic approach based on vertically aligned carbon nanotube forests (VA-CNT forests) and periodic VA-CNT micropillars produced by thermal chemical vapor deposition is explored. In addition, honeycomb-like and flower-like morphologies are created. Initial viability testing reveals that NE-4C neural stem cells seeded on all morphologies survive and proliferate. In addition, free-standing VA-CNT forests and capillary-driven VA-CNT forests are created, with the latter demonstrating enhanced capacity to stimulate neuritogenesis and network formation under minimal differentiation medium conditions. This is attributed to the interaction between surface roughness and 3D-like morphology that mimics the native extracellular matrix, thus enhancing cellular attachment and communication. These findings provide a new avenue for the construction of electroresponsive scaffolds based on CNTs for neural tissue engineering.


Assuntos
Nanotubos de Carbono , Células-Tronco Neurais , Nanotubos de Carbono/química , Engenharia Tecidual , Diferenciação Celular
4.
Bioengineering (Basel) ; 9(6)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35735492

RESUMO

Ankle-foot orthoses (AFO) are prescribed to improve the patient's quality of life. Supporting weak muscles or restraining spastic muscles leads to smoother and more stable locomotion. Commonly, AFO are made using thermoplastic vacuum forming, which requires a long time for production and has limited design options. Additive manufacturing (AM) can solve this problem, leading to a faster and cheaper solution. This review aimed to investigate what is the state-of-art using AM for AFO. Evaluating the used manufacturing processes, customization steps, mechanical properties, and biomechanical features in humans would provide significant insights for further research. The database searches combined AM and AFO with no year or publication type restrictions. Studies must have examined outcomes on human participants with the orthoses built by AM. Other types of orthotic devices or different manufacturing techniques were excluded. Nineteen studies met the inclusion criteria. As stated by having all studies conducted in the last nine years, this is a very recent domain. Different AM processes have been used, with the majority relying on Fused Deposition Modeling. Overall, the manuscripts' quality is deficient, which is critical to promoting further studies with higher samples. Except for one paper, AM-printed AFO was comparable or superior to the thermoplastic vacuum forming AFO in mechanical tests, kinematics, kinetics, and participant feedback.

5.
Macromol Biosci ; 22(1): e2100311, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34610190

RESUMO

Biomimetics offers excellent prospects for design a novel generation of improved biomaterials. Here the controlled integration of graphene oxide (GO) derivatives with a 3D marine spongin (MS) network is explored to nanoengineer novel smart bio-based constructs for bone tissue engineering. The results point out that 3D MS surfaces can be homogeneously coated by layer-by-layer (LbL) assembly of oppositely charged polyethyleneimine (PEI) and GO. Notably, the GOPEI@MS bionanocomposites present a high structural and mechanical stability under compression tests in wet conditions (shape memory). Dynamic mechanically (2 h of sinusoidal compression cyclic interval (0.5 Hz, 0-10% strain)/14 d) stimulates GOPEI@MS seeded with osteoblast (MC3T3-E1), shows a significant improvement in bioactivity, with cell proliferation being two times higher than under static conditions. Besides, the dynamic assays show that GOPEI@MS bionanocomposites are able to act as mechanical stimulus-responsive scaffolds able to resemble physiological bone extracellular matrix (ECM) requirements by strongly triggering mineralization of the bone matrix. These results prove that the environment created by the system cell-GOPEI@MS is suitable for controlling the mechanisms regulating mechanical stimulation-induced cell proliferation for potential in vivo experimentation.


Assuntos
Grafite , Tecidos Suporte , Biomimética , Grafite/química , Grafite/farmacologia , Osteoblastos , Engenharia Tecidual/métodos , Tecidos Suporte/química
6.
J Med Cases ; 12(9): 343-346, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34527102

RESUMO

Therapeutic blockade of tumour necrosis factor alpha (anti-TNF-α) is the mainstay treatment of several rheumatologic diseases. They are unfrequently associated with opportunistic infections and latent tuberculosis (TB) screening is paramount before immunosuppression. A 62-year-old man with psoriatic arthritis was under treatment with adalimumab for over 5 years. The screening for latent tuberculosis infection (LTBI) prior to the start of immunosuppression was negative, and a subsequent interferon gamma release assay 4 years later was also negative. He presented in the emergency department complaining of asthenia, anorexia, fever, night sweats and weight loss for over 5 months. He also complained of memory loss, despite his normal cognitive and neurological examination. After an exhaustive workup, he was diagnosed with a disseminated tuberculosis (cerebral, pulmonary and peritoneal) and treated accordingly. TB diagnosis remains challenging in certain situations. Latent TB screening tests may lack sensitivity and immunosuppressive therapy increases the risk of disseminated infection. We discuss the workup and management of a central nervous system disseminated TB related to adalimumab therapy.

7.
Eur J Case Rep Intern Med ; 8(4): 002422, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33987120

RESUMO

The aetiology of pulmonary nodules is varied, with malignant lesions being the most important and requiring rapid diagnosis and treatment. However, although clinical presentation and imaging may suggest a specific diagnosis, it should be kept in mind that some benign pathologies mimic more serious disease. A 50-year-old man presented with left pleuritic chest pain. A CT scan showed an ipsilateral pulmonary spiculated nodule. Pneumonia was assumed and the patient was started on antibiotic therapy. In the absence of improvement, positron emission tomography and a transthoracic aspiration biopsy were performed. Lung cancer was diagnosed and the patient underwent an upper lobectomy. However, examination of the surgical specimen showed no malignancy. LEARNING POINTS: Although complementary diagnostic exams are increasingly available and widely used, they may produce false positive or false negative results.A correct diagnostic approach can lead to an incorrect diagnosis.The preoperative diagnosis of pulmonary nodules can be a challenge.

8.
J Funct Biomater ; 12(1)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673516

RESUMO

Due to the extremely high incidence of lesions and diseases in aging population, it is critical to put all efforts into developing a successful implant for osteochondral tissue regeneration. Many of the patients undergoing surgery present osteochondral fissure extending until the subchondral bone (corresponding to a IV grade according to the conventional radiographic classification by Berndt and Harty). Therefore, strategies for functional tissue regeneration should also aim at healing the subchondral bone and joint interface, besides hyaline cartilage. With the ambition of contributing to solving this problem, several research groups have been working intensively on the development of tailored implants that could promote that complex osteochondral regeneration. These implants may be manufactured through a wide variety of processes and use a wide variety of (bio)materials. This review aimed to examine the state of the art regarding the challenges, advantages, and drawbacks of the current strategies for osteochondral regeneration. One of the most promising approaches relies on the principles of additive manufacturing, where technologies are used that allow for the production of complex 3D structures with a high level of control, intended and predefined geometry, size, and interconnected pores, in a reproducible way. However, not all materials are suitable for these processes, and their features should be examined, targeting a successful regeneration.

9.
Eur J Case Rep Intern Med ; 8(1): 002219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33585344

RESUMO

Splenosis is a benign condition which results from the self-implantation of splenic tissue on intra or extraperitoneal surfaces, after splenic trauma or splenectomy. Patients are usually asymptomatic but may present with varied symptoms related to the implantation site. The diagnosis is a challenge because abdominal splenosis can mimic several diseases, including neoplasm. The gold standard examination for its diagnosis is scintigraphy with 99mTc-labelled heat-denatured erythrocyte. When splenosis is found in an asymptomatic patient, surgical removal is not indicated. A 57-year-old male patient presented with sporadic epigastric pain and a suspected mass in the recto-sigmoid transition. Abdominal ultrasound, CT and MRI identified this mass, its characteristics and location, but failed to distinguish its nature. However, given the patient's past history of splenectomy and because the mass showed a similar sign to that of the splenic parenchyma, a hypothesis of abdominal splenosis was raised, which was confirmed by scintigraphy with 99mTc-labelled heat-denatured erythrocyte. In this case, the diagnosis was obtained before the patient was subjected to more invasive procedures, which are associated with high morbidity, and, as in most cases, no targeted intervention was necessary. LEARNING POINTS: Increasing numbers of cases of abdominal trauma will result in more frequent splenosis.Diagnosis is sometimes complex as splenosis mimics several diseases.The usual complementary imaging studies often fail to diagnose this entity so clinical suspicion is fundamental for correct diagnosis and treatment.

10.
Foods ; 8(12)2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31756928

RESUMO

Acrylamide (AA), a molecule which potentially increases the risk of developing cancer, is easily formed in food rich in carbohydrates, such as biscuits, wafers, and breakfast cereals, at temperatures above 120 °C. Thus, the need to detect and quantify the AA content in processed foodstuffs is eminent, in order to delineate the limits and mitigation strategies. This work reports the development and validation of a high-resolution mass spectrometry-based methodology for identification and quantification of AA in specific food matrices of biscuits, by using LC-MS with electrospray ionization and Orbitrap as the mass analyser. The developed analytical method showed good repeatability (RSDr 11.1%) and 3.55 and 11.8 µg kg-1 as limit of detection (LOD) and limit of quantification (LOQ), respectively. The choice of multiplexed targeted-SIM mode (t-SIM) for AA and AA-d3 isolated ions provided enhanced detection sensitivity, as demonstrated in this work. Statistical processing of data was performed in order to compare the AA levels with several production parameters, such as time/cooking temperature, placement on the cooking conveyor belt, color, and moisture for different biscuits. The composition of the raw materials was statistically the most correlated factor with the AA content when all samples are considered. The statistical treatment presented herein enables an important prediction of factors influencing AA formation in biscuits contributing to putting in place effective mitigation strategies.

11.
J Aging Res ; 2019: 1935806, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31192012

RESUMO

Osteoarthritis (OA) is a degenerative disease, promoted by abnormal chronic mechanical loading over the joint, for instance, due to excessive body mass. Patients frequently report pain, fatigue, and limitations in specific functional daily activities. Regarding the treatment of OA, two nonpharmacological options are available. However, it is not clear which type and intensity of exercise have better outcomes in treatment and how tissue engineering can be a promising field due to the mechanical load implants will suffer. The aims of this work were to investigate (1) the main characteristics, prevalence, and consequences of OA; (2) the exercise prescription guidelines and whether exercise interventions have a positive effect on OA treatment; and (3) the novel improvements on tissue engineering for OA treatment. Both patients and practitioners should be aware that benefits may come from prescribed and supervised exercise. Recent studies have highlighted that an optimal balance between exercise and nutritional income should be widely recommended. Regarding tissue engineering, significant steps towards the development of implants that mimic the native tissue have been taken. Thus, further studies should focus on the impact that exercise (repetitive loading) might have on cartilage regeneration. Finally, suggestions for future research were proposed.

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