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Nanoparticles for Bone Tissue Engineering
Published in Klaus D. Sattler, st Century Nanoscience – A Handbook, 2020
Cristiana Gonçalves, Isabel M. Oliveira, Rui L. Reis, Joaquim M. Oliveira
Bone diseases encompass all the diseases and injuries affecting the skeletal system of the human body and can be due to several causes, such as metabolic origin, inflammation, bone resorption and others. These defects may negatively affect the structural stability and the biomechanical function of bones. Bone regeneration has been an important challenge in clinical surgery, due to conditions such as trauma, tumor and diseases (e.g., osteomyelitis and osteitis), with the existing therapeutic and research approaches not sufficiently effective due to several limitations (Torgbo and Sukyai, 2018). In fact, one of the main challenges of TERM is precisely bone tissue regeneration (Vieira et al., 2017). Moreover, it was three decades ago that the field of bone tissue engineering (BTE) had started to form, showing since then an increasingly fast pace of development (Amini et al., 2012; Henkel et al., 2013).
Cadmium Exposure and Toxicity
Published in Debasis Bagchi, Manashi Bagchi, Metal Toxicology Handbook, 2020
Soisungwan Satarug, Kenneth R. Phelps
The skeleton remodels itself in isolated bone multicellular units (BMUs) through sequential resorption by osteoclasts, production of osteoid matrix by osteoblasts, and mineralization of matrix with hydroxyapatite (Raisz, 2005). Although remodeling occurs in both cortices and trabecules, it is conventionally analyzed with histomorphometry of undecalcified sections of trabecular bone (Kulak and Dempster, 2010). Disorders of remodeling, the so-called metabolic bone diseases, include osteomalacia, osteoporosis, and osteitis fibrosa (OF). In osteomalacia, normal matrix production is followed by defective mineralization. Sequelae include weakness, generalized aching, and painful unicortical fractures (Looser’s zones) (Fukumoto et al., 2015).
Development and Application of Phase Change Materials in the Biomedical Industry
Published in Atul Sharma, Amritanshu Shukla, Renu Singh, Low Carbon Energy Supply Technologies and Systems, 2020
Abhishek Anand, Amritanshu Shukla, Atul Sharma
A BU is a chronic enervating disease caused by Mycobacterium ulcernas. The organism belongs to the class of bacteria that causes tuberculosis and leprosy. It affects the skin but sometimes bones. The lesion caused by BU is shown in Figure 18.2. It leads to permanent disfigurement and long-term disability. The mode of spread is largely unknown. The disease is pandemic in tropical and subtropical countries. According to the World Health Organization (WHO), it is reported in more than 33 countries of this region. Out of these, 13 countries regularly report to WHO. It is most prevalent in West and Central Africa, including Ghana, Congo, Benin, Cameroon, and Côte d’Ivoire (Combe et al. 2017). In recent times, the cases of BU have risen in Australia and Nigeria. The cases are reported equally among males and females. The lesions are reported mainly in limbs that consist of 35% on upper limbs, 55% on lower limbs, and remaining from other parts of the body. There are three subcategories of BUs. Category I consists of single small lesions with 35% cases, Category II consists of a non-ulcerative and ulcerative plaque and oedematous forms with 35% cases, and Category III has disseminated and mixed forms such as osteitis, osteomyelitis, and joint involvement with remaining 33% cases. In all countries, 70% of cases are reported in the ulceration stage. The Mycobacterium ulcernas grows at a temperature between 30°C–33°C. It further produces a harmful toxin known as mycolactone responsible for damage to the skin tissues and hampering the proper functioning of the immune defense system. The BU initially develops with painless swelling. The mycolactone impedes the local immune response, causing the impairment of skin. It further aggravates, causing gross deformities of bones. The research still has not established its mode of transmission. The BU is most normally diagnosed with an IS2404 polymerase chain reaction. The treatment generally includes a combination of antibiotics, such as rifampicin, streptomycin, and clarithromycin. Bacillus Calmette–Guérin (BCG) vaccine is administered for restricted protection. Drug treatment has several limitations. Antibiotics are not always safer and have their own side effects. Children and pregnant women are most vulnerable and not recommended for these combinations. The alternative treatment conveniently employed is thermotherapy. Because bacteria cannot grow above 37°C, thermotherapy above this temperature is quite effective for the killing and proliferation of germs. The heat treatment with PCM is gaining importance in remote and resource-scare countries. It is largely recommended because of its low cost, reliability, and rechargeability of PCM.
Does inside passing contribute to the high incidence of groin injuries in soccer? A biomechanical analysis
Published in Journal of Sports Sciences, 2018
Thomas Dupré, Johannes Funken, Ralf Müller, Kristian R. L. Mortensen, Filip Gertz Lysdal, Markus Braun, Hartmut Krahl, Wolfgang Potthast
High muscle stresses in the adductors cannot only explain muscle injuries, a connection can also be made to the development of adductor tendinopathy and osteitis pubis: The cross-sectional area of muscles gets smaller towards their apophyses, but the forces produced are constant throughout the entire muscle. Therefore, the stress applied to the tendons and apophyses is higher compared to the centre of the muscle. This even higher stress makes the tendons and apophyses prone to overuse and the onset of inflammations. Accordingly, this is relevant for the development of adductor tendinopathy in soccer players. Furthermore, because the gracilis, together with the adductor longus, is attached to the pubic bone via the inferior pubic ligament, the combined force of the two muscles acts on the pubic symphysis (Cunningham et al., 2007). There are two mechanisms associated with groin pain and/or osteitis pubis that might be explained by this combined force: First, Cunningham et al. (2007) found that osteitis pubis is often accompanied by a microtear in the adductor longus attachment. Second, due to the high stresses, the pubic symphysis and parasymphyseal bone might be put under extensive stress repeatedly, leading also to osteitis pubis (Hiti et al., 2011). Both mechanisms can be explained by high muscle stress acting on the apophysis and pubic symphysis.
The practical application of a method of analysing the variability of within-step accelerations collected via athlete tracking devices
Published in Journal of Sports Sciences, 2020
The classification system used in this study, although developed for the use at a single professional AFL club, will share many similarities with similar classification systems used in other environments. For example, Rogalski et al.(2013) investigated the relationship between training load and injury risk in an elite AFL population, and a similar classification method was described for the AFL club who provided the subjects for the study. In addition, combining musculoskeletal and other injuries such as osteitis pubis in the “groin” classification is consistent with the report on injuries published by the league itself (Orchard, Seward, & Orchard, 2014).
Groin injury risk of pubertal soccer players increases during peak height velocity due to changes in movement techniques
Published in Journal of Sports Sciences, 2020
Thomas Dupré, Wolfgang Potthast
Mean estimated age at PHV was similar to previous studies (Bult et al., 2018; Philippaerts et al., 2006). Gripping force and height measurements have been used to investigate accelerated development during adolescence (Backous et al., 1990). Backous and colleagues associated being tall (>165 cm), due to advanced maturity, but weak (<245.25 N) with an increased injury risk (Backous et al., 1990, 1988). In our study, none of the 22 participants fit in the tall but weak category. This might be attributed to the small sample size in our study, but could also be explained by the sample investigated by Backous and colleagues, where the participants seem to have been overweight (Backous et al., 1990) and not as physically active as our population. Nevertheless, our results showed significantly increased weight and height in the MID group, with large effect sizes. The two force measurements were not significantly different but showed medium effect sizes regarding the differences between PRE and MID. This indicates an asynchronous development of the anthropometrics and muscle forces and is likely to be grounded on the same basis as the results by Backous and colleagues. In a previous study of our group, we speculated about the anthropometric parameters increasing faster than the muscular capacity and the supposed higher injury risk associated with this (Dupré et al., 2020). The moments of inertia increase synchronous with the anthropometrics, demanding higher forces from the muscles to accelerate the body’s segments. If the muscles and tendons are unable to adapt quickly, overuse injuries like osteitis pubis and other GI-related injuries are likely to occur. Furthermore, such an imbalanced development might also result in changes to the movement techniques. Interestingly, the only significant difference in the time series between PRE and MID was found during terminal stance of the CM, where MID had a higher abduction moment (see Figure 3). As written above, terminal stance is the movement phase where the occurrence of GI is most likely. A higher external abduction moment of the MID group during terminal stance indicates a higher load for the adductor muscles of the respective group. From this follows that the MID group uses a movement strategy that makes greater use of the hip adductor muscles in the movement phase most common for GI. Thereby they increase their injury risk in addition to the injury risk caused by the growth spurt (Backous et al., 1988; Bult et al., 2018; Dupré et al., 2020). Contrary to the expectations, there was no significant difference in the muscle forces of CM, although MID had a higher abduction moment and significantly increased anthropometrics. MID might have reduced their acceleration during push of phase compared to PRE in order to reduce the required adductor forces.