611 research outputs found

    Examining the Forces Associated with Heading in Collegiate Soccer Athletes

    Get PDF
    Context: Repetitive sub-concussive impacts have recently been recognized as a contributing factor of long-term cognitive deficits. The potential for this to affect soccer players participating at a high level is great due to the constant intentional use of the unprotected head when playing. Examining the force with which a soccer ball strikes an athlete\u27s head during the act of heading is important to determine if there is a potential risk for long term consequences. Objective: The purpose of this study was to determine how much force is associated with heading in soccer. The variability between goal and corner kicks and throw-ins were examined. A secondary purpose was to determine if this information is indicative of soccer players potentially being at risk due to repetitive sub-concussive impacts. Design: This was a prospective descriptive study which examined the forces transferred from a soccer ball to the head during simulated soccer heading scenarios. Setting: Collegiate soccer conditions in the Mid-Atlantic part of the country. Patients and Other Participants: Using a sample of convenience, three male collegiate soccer players between the ages of 19-22 playing at a D1 level at the time of the study were used. Subjects were selected if they headed the ball five or more times in a game, had five or more years of playing experience at the time of the study and had not had any head or neck injuries in the six months preceding the study. Interventions: Each subject went through a series of 3 different heading scenarios, heading the ball 5 times for each scenario. Heading was done with goal kicks, corner kicks and throw-ins. Pressure film on the subjects\u27 head recorded the force during the act of heading. Film was changed following each header and then sent to the lab for analysis. The analysis included minimum, maximum and average pressure. Main Outcome Measures: The forces recorded with heading the soccer ball during all three heading scenarios will be comparable to the numbers seen with football and ice hockey players. The forces seen with a goal kick will be higher on average than those recorded with corner kicks and throw-ins. Results: Ball speeds were found to range from 26-57 mph across 42 trials of three different heading scenarios. Goal kicks were found to produce the highest speeds and forces recorded with throw-in\u27s produced the lowest speeds and forces. Forces ranged from 364.34 lbf -- 1070.18 lbf. Conclusions: Current research suggests that while the forces acting on the head during heading are below the accepted value for concussion there is still a risk for cumulative damage secondary to repetitive impacts sustained at sub-concussive levels. Further examination of duration of impact, acceleration/deceleration of the head and cognitive testing in former players who were considered headers is suggested to better understand the risk posed by repetitive heading

    Gingival hyperplasia around dental implants in jaws reconstructed with free vascularized flaps: a case report series

    Get PDF
    Free vascularized flaps are the gold standard for reconstruction of the facial skeleton after surgical ablation of pathologies or when important atrophy of the jaws exists. A frequent problem seen during prosthetic rehabilitation after reconstruction with free vascularized flaps is the onset of hyperplastic granulomatous reactive tissue around the prosthetic abutment of the implant. The features of this phenomenon seem to be directly related to the characteristics of the periimplant tissue and of the manufacturing materials of the prosthesis and abutments. This complication can be seen quite often; we found it in 7 of 40 patients (17.5%). It does not seem to significantly affect the survival rate of implants. The aim of the study was to analyze the behavior of such lesions and to suggest our clinical approach with the management of these kinds of patients and complications. To remove gingival hyperplasia, we used either a traditional cold scalpel or an electric cautery or laser. We had good results using these tools. The onset of this phenomenon was not influenced by either the kind of implant and free flaps used or by the local conditions of the patients (such as radiotherapy). The number of recurrences was highly influenced by the oral hygiene of the patients

    Olive leaf extract inhibits metastatic melanoma spread through suppression of epithelial to mesenchymal transition

    Get PDF
    Olive tree leaves are an abundant source of bioactive compounds with several beneficial effects for human health, including a protective role against many types of cancer. In this study, we investigated the effect of an extract, obtained from olive tree (Olea europaea L.) leaves (OLE), on proliferation, invasion, and epithelial to mesenchymal transition (EMT) on metastatic melanoma, the highly aggressive form of skin cancer and the deadliest diseases. Our results demonstrated that OLE inhibited melanoma cells proliferation through cell cycle arrest and induction of apoptotic cell death. Moreover, OLE suppressed the migration, invasion, and colonies formation of human melanoma cells. Similar to our in vitro findings, we demonstrated that the oral administration of OLE inhibited cutaneous tumor growth and lung metastasis formation in vivo by modulating the expression of EMT related factors. In addition, the anti-proliferative and anti-invasive effects of OLE against melanoma were also related to a simultaneous targeting of mitogen-activated protein kinase and PI3K pathways, both in vitro and in vivo. In conclusion, our findings suggest that OLE has the potential to inhibit the metastatic spread of melanoma cells thanks to its multifaceted mechanistic effects, and may represent a new add-on therapy for the management of metastatic melanoma

    Free boundary problem for the role of planktonic cells in biofilm formation and development

    Full text link
    The dynamics of biofilm lifecycle are deeply influenced by the surrounding environment and the interactions between sessile and planktonic phenotypes. Bacterial biofilms typically develop in three distinct stages: attachment of cells to a surface, growth of cells into colonies, and detachment of cells from the colony into the surrounding medium. The attachment of planktonic cells plays a prominent role in the initial phase of biofilm lifecycle as it initiates the colony formation. During the maturation stage, biofilms harbor numerous microenvironments which lead to metabolic heterogeneity. Such microniches provide conditions suitable for the growth of new species, which are present in the bulk liquid as planktonic cells and can penetrate the porous biofilm matrix. We present a 1D continuum model on the interaction of sessile and planktonic phenotypes in biofilm lifestyle which considers both the initial attachment and colonization phenomena. The model is formulated as a hyperbolic-elliptic free boundary value problem with vanishing initial value. Hyperbolic equations reproduce the transport and growth of sessile species, while elliptic equations model the diffusion and conversion of planktonic cells and dissolved substrates. The attachment is modelled as a continuous, deterministic process which depends on the concentrations of the attaching species. The growth of new species is modelled through a reaction term in the hyperbolic equations which depends on the concentration of planktonic species within the biofilm. Existence and uniqueness of solutions are discussed and proved for the attachment regime. Finally, some numerical examples show that the proposed model correctly reproduces the growth of new species within the biofilm and overcomes the ecological restrictions characterizing the Wanner-Gujer type models.Comment: 17 pages, 9 figures, preprint versio

    CO2 laser ablation of oral leukoplakia: with or without extension of margins?

    Get PDF
    The purpose is to determine the sufficient extension of margins during laser ablation of oral leukoplakia and observe its short-term recurrence rate. Materials and Methods.The study was designed as a randomized controlled clinical trial was conducted on 33 oral leukoplakia lesions diagnosed in 30 patients (16 Females and 14 Males) with an age range between 39 and 79 years. The lesions were divided into three groups; Group A: 11 lesions in 11 patients, in which the laser ablation was done for the entire lesion without extension of margins; Group B: 11 lesions in 8 patients, in which the laser ablation was done for the lesion adding at least 3mm extension of margins; and finally the Group Control: consists of 11 untreated lesions in 11 patients, in which only “wait and see” approach was done. Results. Complete healing of 13 lesions occurred in both groups A and B. Complete regression of 3 lesions occurred in Group Control. After 6 months of follow-up, 6 of 9 lesions in both groups A and B that showed the recurrence, had shown an initial recurrence after 3 weeks of the laser ablation. Patients with no history of smoking habits showed complete healing of 87.5%, while in ex-smokers complete healing was 42.8%. The statistical analysis was performed, and the averages of all groups are significantly different (p <0.00001).Discussion.The primary treatment focuses on the elimination of associated risk factors (smoking, alcohol, and local irritating factors). In the literature, the recurrence rate varies between 13.6% and 40.7%, while in our study, it was 45.5% in Group A and 36.4% in Group B. Conclusion.The recommended extension of margins should be at least 3mm in width. Further research can be performed to evaluate the immediate re-ablation of the lesions which showed an initial recurrence after 3 weeks of laser ablation

    Different water and light regimes affect ionome composition in grapevine (Vitis vinifera L.)

    Get PDF
    Many inorganic cations play a major role in winemaking processes and wine quality. For this reason, chemistry at the elemental level ("ionomic") of the grape berry is of concern not only to the viticulturist, but also to the oenologist due to their direct impact on juice and must composition, which in turn affect wine quality. The aim of this research was to evaluate the effect of reduced irrigation and incident light (by means of micronized calcite) on the berry skin ionome of the Italian red grape 'Aglianico'. The study was carried out in a five-years-old vineyard (Vitis vinifera L. 'Aglianico') located in Southern Italy. Half of the plants (IRR) were drip irrigated, whereas the other half were not irrigated (NIR). Half of IRR and NIR plants were treated with Megagreen® micronized calcite. In all the treatments, plant water status and gas exchange were determined. The mean values of stem water potential (ψw) during the experiment were –1.02 and –1.10 MPa in IRR and NIR, respectively. The calcite treatments did not show changes in ψw values if compared to the untreated ones. The values of gas exchange were not statistically different among the four treatments. Grape berries were separated into three groups of mass, and the levels of macroelements, microelements and lanthanides were measured. Irrigation and calcite significantly affected macroelements distribution in all the three groups of mass, with Fe, Cu and Zn being significantly higher in the IRR and calcite-treated treatments. The effect of irrigation on the changes in microelement levels was significant for some elements. Calcite-treated vines showed higher mean values of Co, Cd, Hg and Pb. Regarding lanthanides, in calcite-untreated vines, irrigation determined significant decreases in average La, Ce, Nd, whereas in calcite-treated vines, increases in the mean concentrations of Ce, Nd, Sm, Gd, Dy, Er and Yb were found. Generally, lanthanide levels did not change between calcite-treated and untreated vines, and in all the treatments Lu resulted to be the most abundant one. Macroelements, microelements and lanthanide levels generally decreased with decreasing berry weight. The dynamics of the extractability of metals from grape berries to must during fermentation could be used to predict wine quality during the following processes and for wine traceability purposes.

    Use of systemic and in situ lactoferrin in MRONJ surgical management: proposal for a therapeutic solution

    Get PDF
    Aim: Lactoferrin (Lf) is an antimicrobial and iron chelator glycoprotein contained in exocrine secretion, including saliva, and in secondary granules of neutrophil granulocytes. Lf performs its antibacterial and antiviral action through two pathways: the first deprives bacteria of the iron they need for their reproduction and for biofilm formation; the second contributes to restore the inflammatory homeostasis which is essential for tissue health modulating the level of cytokines, like IL-6. The study intends to propose the use of systemic and in situ Lf effectiveness in the healing of oral mucosa and bone tissue affected by medication-related ostenecrosis of the jaw (MRONJ), after surgical excision or spontaneous elimination of necrotic bone

    Bone damage induced by different cutting instruments: an in vitro study

    Get PDF
    The aim of this study was to compare the peripheral bone damage induced by different cutting systems. Four devices were tested: Er:YAG laser (2.94 mm), Piezosurgery, high-speed drill and low-speed drill. Forty-five bone sections, divided into 9 groups according to different parameters, were taken from pig mandibles within 1 h post mortem. Specimens were fixed in 10% buffered formalin, decalcified and cut in thin sections. Four different parameters were analyzed: cut precision, depth of incision, peripheral carbonization and presence of bone fragments. For statistical analysis, the Kruskal-Wallis test was applied to assess equality of sample medians among groups. All sections obtained with the Er:YAG laser showed poor peripheral carbonization. The edges of the incisions were always well-shaped and regular, no melting was observed. Piezosurgery specimens revealed superficial incisions without thermal damage but with irregular edges. The sections obtained by traditional drilling showed poor peripheral carbonization, especially if obtained at lower speed. There was statistically significant differences (p<0.01) among the cutting systems for all analyzed parameters. Er:YAG laser, gave poor peripheral carbonization, and may be considered an effective method in oral bone biopsies and permits to obtain clear and readable tissue specimens

    Subcutaneous emphysema during third molar surgery: a case report

    Get PDF
    Extraction of third molars is the most common surgical procedure performed in oral surgery on a daily basis and, despite surgical skills and expertise, complications may occur. Complications observed during or after third molar removal may include pain, swelling, bleeding, infection, sinus perforation and nerve damage. Fortunately, with a proper management and a good surgical technique, the incidence of such events is low. Subcutaneous emphysema associated with dental extraction occurs when the air from the high-speed dental handpiece is forced into the soft tissue through the reflected flap and invades the adjacent tissues, leading to swelling, crepitus on palpation and occasionally spreading through the tissue spaces of the fascial planes. Although rare, iatrogenic subcutaneous emphysema can have serious and potentially life-threatening consequences. Care should be taken when using air-driven handpieces. The access of air into the facial tissues is not limited to tooth extractions, but may also occur through other portals of entrance, such as endodontically treated teeth, periodontium and lacerations of intraoral soft tissues. When subcutaneous emphysema occurs, it must be quickly diagnosed and properly managed to reduce the risk of further complications. This report presents a case of subcutaneous emphysema occurred during extraction of a mandibular third molar extraction with the use of an air turbine handpiece. Case management is described and issues relative to the diagnosis and prevention of this surgical complication are discussed
    corecore