2,057 research outputs found

    Characterization of the immune cells response and ultrastructural study of dendritic cell Golgi Apparatus role in ORF virus infection

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    Contagious Ecthyma is an acute skin anthropozoonosis caused by orf virus (ORFV), which affects sheep and goat. The infectious agent is an epitheliotropic, double- stranded DNA poxvirus. Infection happens via the hurt skin, and causes a localized virus production in the epidermal cells and keratinocytes. This paper characterize the cellular immune response by cytochemistry in ORFV infection and studies the role of Golgi Apparatus (GA) of keratinocytes by transmission electron microscopy (TEM) and 3D models. Twenty cutaneous biopsies in sheep from ORFV infected lesions were fixed in 10% formalin and embedded in paraffin for light microscopy. Paraffin sections were immunocytochemically stained (DAKO LSAB+/HRP) to identify major histocompatibility complex (MHC) II, CD1, CD79a, CD3, TCRγδ, and CD21. Furthermore, a portion from the biopsies was fixed with 1% glutaraldehyde/0.1M Na-cacodylate buffer, post-fixed in cacodylate buffer/1% osmium tetroxide and embedded in Durcupan for TEM. Ultrathin sections were observed and marked for MHC II with 10 nm gold particles. Three-dimensional computer-generated GA models were reconstructed from serial ultrathin sections. Light microscopy images showed keratinocites positive for MHC II and negative for CD1, supporting the idea that Langerhans cells start the skin immune response. Positive cells for TCRγδ/CD3, CD21 and CD79a suggested the prevailing attraction for dendritic cells instead of T and B cells. Transmission electron micrographs revealed poxvirus-like particles. The images of GA showed the presence of large structures with bud profiles in the process of fusing with a Golgi stack and appeared emptying its ORFV content into it. ORFV induced swelling of Golgi vesicles, and perforation and fragmentation of GA, leading to a disorganized structure. Lateral vesicles close the Golgi stack were positive for MHC II, but in heavy infected cells the Golgi structures positive for MHC II were dispersed into the cytoplasm. An increased distance between GA and cell nucleus in infected cells was detected. Computer 3D reconstructions clarify the dynamics of GA in ORFV infected cell. Overall, these results suggest that ORFV targets the vesicular export machinery and the structure and function of the GA might aid to escape cellular immune recognition

    Effects of training fatigue on performance

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    Training exposes athletes to various types of load, often beyond their tolerance threshold. This, without adequate recovery, leads to the accumulation of fatigue. Fatigue can negatively affect the athlete's performance capabilities in terms of force production and motor control. Coaches should have knowledge of the effects of fatigue in order to better plan training avoiding phenomena that qualitatively and quantitatively limit performance or the occurrence of injuries. The aim of the work is to clarify the effects of exercise-induced fatigue, differentiating between central fatigue and peripheral fatigue, in order to provide correct information to develop specific post-exercise and post-workout recovery strategies. The study was carried out through the recognition, by PRISMA method, in the scientific literature of the theories and practices validated and disseminated in the world of sport to optimize training plans. The study reveals a differentiation on the origin of fatigue: in fact, we speak of central fatigue and peripheral fatigue. Both have different effects on the muscle response to training. For this reason, it must be considered differently in the management of loads, in terms of intensity, volume, frequency and density, in order to optimize the programming for reaching the peak performance, without overtraining. The data have been utilized by personal trainer to plan for every type of athlete to reach a better individual performance

    Approaches to motor learning: Cognitive approach versus ecological dinamyc one

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    The aim is to deepen the knowledge on the scientific evidence between the biomedical and pedagogical part and on the differences of the two approaches commonly used for teaching / learning processes: the cognitive and ecological-dynamic approach on one's own characteristics and specific paradigms. The retrieval of scientific literature took place through the use of specialized web research on: PubMed, Google Scholar, Scopus, PMCfreearticle, CrossRef by PRISMA method. Motor learning is the stabilized execution of a given movement, executive technique, or gesture. It means that in the face of a number of repetitions most are performed correctly. Cognitive approach places the person at the centre of the teaching / learning process, neglecting the inferences that the surrounding environment produces. Ecological-dynamic approach, which considers motor coordination as an organization emerging from the peripheral constraints of the system rather than from central control structures, is defined as ecological, since it does not consider the aspects of motor coordination within the individual but, more generally, the complex interaction between the individual and the environment and the circular relationship between perception and action. The characteristics and paradigms of two approaches highlight two opposite ways to motor learning with an unsolved problem on which one is correct to use in physical education and sports performance

    Muscle strength and the complexity of human movement

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    The mechanisms that influence the ability to produce muscle force are to be found not only in structural or biomechanical elements, but also in factors inherent to inter and intramuscular control and coordination. In the execution of the motor gesture, the body, functioning as a system, produces a quantity of force which, to be effective for the intended purposes, must be managed and integrated by the nervous system. The various expressions of force must be considered in relation to the function. Too often, motor and sports training specialists focus on the development of strength in a rigid and standardized way, following pre-established patterns for every need. The objective of the study is to increase the knowledge of the characteristics that distinguish the different types of force expression through an approach that emphasizes their functionality. Through the PRISMA method, search engines (PubMed, Google Scholar, Scopus, PMCfreearticle, CrossRef). In conclusion, the study provides an alternative interpretation of the force that is expressed in different ways in relation to the purpose, leaving out, for this reason, reductionist classifications, not very applicable to biological systems

    Inclusive Physical Activity to Promote the Participation of People with Disabilities: A Preliminary Study

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    Background: Physical activity brings improvements in the quality of life in all individuals, disabled and non-disabled. There is little evidence in the literature of inclusive physical activity in which disabled and non-disabled people participate at the same level. Objectives: The study aimed to demonstrate the effectiveness of an inclusive training program, structured in such a way as to encourage physical activity for all participants with and without disabilities, in improving body composition, explosive strength, and endurance. Methods: A sample of twenty-four subjects (mean age: 24.09±3.92 years), 12 disabled and 12 non-disabled, was selected. Quantitative input and output data were recruited at 16-week intervals using a battery of tests: anthropometric measurements, Vertec Squat Jump test, and Yoyo Endurance Test. During the 16 weeks, all participants followed an appropriately structured training program in four mesocycle without any differences. Input and output data were compared employing the t-test for dependent samples. Results and conclusions: The results showed statistically meaningful improvements at an alpha level set at 0.05 for the three parameters tested. These results confirmed the effectiveness of the proposed inclusive training protocol on the improvement of the tested parameters in all participants. These strategies didn't jeopardise the achievement of the overall objectives set; on the contrary, improvements in BMI, explosive strength, and endurance strength of 4.8%, 4.3%, and 56.2% respectively were observed

    Anisakis pegrefii and Anisakis simplex sensu strictu in Mediterranean sea

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    BACKGROUND: Anisakiasis is a parasitic zoonosis caused by ingestion of nematode larvae belonging to Anisakidae family, following consumption of raw, undercooked or improperly processed fish. Mediterranean sea represent an aquatic ecosystem particularly suitable for the development of Anisakid larvae. The aim of this work is to found intra-species and inter-species nucleotide differences by phylogenetic analysis in this geographical area. METHODS: In the period from January to November 2013, 584 fish from Mediterranean sea were screened, and they were found parasitised of 6318 type I anisakid larvae. Fish were eviscerated and observed by stereo microscope to collect larvae relived in the viscera, organs and muscles. After genus identification, the larvae were subjected to molecular analysis by extraction of DNA, amplification of ITS gene and restriction enzyme. PCR products were sequenced and the sequences were analyzed and aligned to examine the relationship of nucleotides. RESULTS: The anisakid species we have identified were Anisakis pegreffii and Anisakis simplex s.s.. Phylogenetic analysis detects nucleotide differences between the two species. In the positions 251 and 267 was found a Cytosine in Anisakis pegreffii and a Thymine in Anisakis simplex s.s., respectively. No difference was found in Anisakis pegreffii specie becoming from different fish of different areas. CONCLUSIONS:. The parasite DNA were amplified and sequenced to identify any nucleotide differences between the different species as well as within the same species.No intra-species sequence differences were found in Anisakis pegreffii. Two inter-species differences were found between Anisakis pegreffii and Anisakis simplex. Further studies will be conducted to confirm nucleotide differences in other target genes
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