Mechanical competence of ovariectomy-induced compromised bone after single or combined treatment with high-frequency loading and bisphosphonates

Osteoporosis leads to increased bone fragility, thus effective approaches enhancing bone strength are needed. Hence, this study investigated the effect of single or combined application of high-frequency (HF) loading through whole body vibration (WBV) and alendronate (ALN) on the mechanical competence of ovariectomy-induced osteoporotic bone. Thirty-four female Wistar rats were ovariectomized (OVX) or sham-operated (shOVX) and divided into five groups: shOVX, OVX-shWBV, OVX-WBV, ALN-shWBV and ALN-WBV. (Sham)WBV loading was applied for 10 min/day (130 to 150 Hz at 0.3g) for 14 days and ALN at 2 mg/kg/dose was administered 3x/week. Finite element analysis based on micro-CT was employed to assess bone biomechanical properties, relative to bone micro-structural parameters. HF loading application to OVX resulted in an enlarged cortex, but it was not able to improve the biomechanical properties. ALN prevented trabecular bone deterioration and increased bone stiffness and bone strength of OVX bone. Finally, the combination of ALN with HF resulted in an increased cortical thickness in OVX rats when compared to single treatments. Compared to HF loading, ALN treatment is preferred for improving the compromised mechanical competence of OVX bone. In addition, the association of ALN with HF loading results in an additive effect on the cortical thickness

Balancing the immune response in the brain: IL-10 and its regulation

Background: The inflammatory response is critical to fight insults, such as pathogen invasion or tissue damage, but if not resolved often becomes detrimental to the host. A growing body of evidence places non-resolved inflammation at the core of various pathologies, from cancer to neurodegenerative diseases. It is therefore not surprising that the immune system has evolved several regulatory mechanisms to achieve maximum protection in the absence of pathology. Main body: The production of the anti-inflammatory cytokine interleukin (IL)-10 is one of the most important mechanisms evolved by many immune cells to counteract damage driven by excessive inflammation. Innate immune cells of the central nervous system, notably microglia, are no exception and produce IL-10 downstream of pattern recognition receptors activation. However, whereas the molecular mechanisms regulating IL-10 expression by innate and acquired immune cells of the periphery have been extensively addressed, our knowledge on the modulation of IL-10 expression by central nervous cells is much scattered. This review addresses the current understanding on the molecular mechanisms regulating IL-10 expression by innate immune cells of the brain and the implications of IL-10 modulation in neurodegenerative disorders. Conclusion: The regulation of IL-10 production by central nervous cells remains a challenging field. Answering the many remaining outstanding questions will contribute to the design of targeted approaches aiming at controlling deleterious inflammation in the brain.We acknowledge the Portuguese Foundation for Science and Technology (FCT) for providing a PhD grant to DLS (SFRH/BD/88081/2012) and a post-doctoral fellowship to SR (SFRH/BPD/72710/2010). DS, AGC and SR were funded by FEDER through the Competitiveness Factors Operational Programme (COMPETE) and National Funds through FCT under the scope of the project POCI-01-0145-FEDER007038; and by the project NORTE-01-0145-FEDER-000013, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). The MS lab was financed by Fundo Europeu de Desenvolvimento Regional (FEDER) funds through the COMPETE 2020—Operacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through FCT in the framework of the project “Institute for Research and Innovation in Health Sciences ” (POCI-01-0145-FEDER-007274). MS is a FCT Associate Investigator. The funding body had no role in the design of the study and collection, analysis, and interpretation of the data and in writing the manuscript

Diet Quality and Dietary Intake in Breast Cancer Survivors Suffering from Chronic Pain: An Explorative Case-Control Study

Background/Objectives: Dietary factors may significantly influence pain management in cancer survivors. However, a substantial gap exists regarding the relationship between nutrition and chronic pain in this population. This study examined differences in diet quality and dietary intake between breast cancer survivors (BCS) experiencing chronic pain and healthy controls (HC). It also aimed to understand the associations between dietary elements and pain-related outcomes within the BCS group. Methods: A case-control study was conducted with 12 BCS experiencing chronic pain and 12 HC (ages 18–65). Data collection included body composition, experimental pain assessments, pain-related questionnaires, and a 3-day food diary to calculate diet quality using the Healthy Eating Index-2015 (HEI-2015) and Dietary Inflammatory Index (DII). Statistical analyses evaluated group differences and associations between dietary factors and pain within the BCS group. Results: There were no significant differences in HEI-2015 scores between BCS and HC, but BCS had a significantly lower DII score (p = 0.041), indicating a more anti-inflammatory diet. BCS also showed higher intake of omega-3, vitamins B6, B12, A, D, and magnesium (p < 0.05). While total diet quality scores did not correlate with pain outcomes, several HEI-2015 and DII components, such as dairy, sodium, protein, vitamin C, and vitamin D, showed moderate positive or negative correlations with pain measures. Conclusions: Despite no overall differences in diet quality, BCS with chronic pain consumed more anti-inflammatory nutrients than HC. Complex correlations between specific dietary components and pain outcomes emphasise the need for further research to explore these links for chronic pain management in BCS

Clinical management and microscopic characterisation of fatique-induced failure of a dental implant. Case report

BACKGROUND: Osseointegrated endosseous implants are widely used for the rehabilitation of completely and partially edentulous patients, being the final prosthodontic treatment more predictable and the failures extremely infrequent. A case of fracture of an endosseous dental implant, replacing the maxillary first molar, occurring in a middle-age woman, 5 years after placement is reported. MATERIALS AND METHODS: The difficult management of this rare complication of implant dentistry together with the following rehabilitation is described. Additionally, the authors performed an accurate analysis of the removed fractured implant both by the stereomicroscope and by the confocal laser scanning microscope. RESULTS AND DISCUSSION: The fractured impant showed the typical signs of a fatigue-induced fracture in the coronal portion of the implant together with numerous micro-fractures in the apical one. Three dimensional imaging performed by confocal laser scanning microscope led easily to a diagnosis of "fatigue fracture" of the implant. The biomechanical mechanism of implant fractures when overstress of the implant components due to bending overload is discussed. CONCLUSION: When a fatigue-induced fracture of an dental implant occurs in presence of bending overload, the whole implant suffers a deformation that is confirmed by the alterations (micro-fractures) of the implant observable also in the osseointegrated portion that is easily appraisable by the use of stereomicroscope and confocal laser scanning microscope without preparation of the sample

Entropy production and Lyapunov instability at the onset of turbulent convection

Computer simulations of a compressible fluid, convecting heat in two dimensions, suggest that, within a range of Rayleigh numbers, two distinctly different, but stable, time-dependent flow morphologies are possible. The simpler of the flows has two characteristic frequencies: the rotation frequency of the convecting rolls, and the vertical oscillation frequency of the rolls. Observables, such as the heat flux, have a simple-periodic (harmonic) time dependence. The more complex flow has at least one additional characteristic frequency -- the horizontal frequency of the cold, downward- and the warm, upward-flowing plumes. Observables of this latter flow have a broadband frequency distribution. The two flow morphologies, at the same Rayleigh number, have different rates of entropy production and different Lyapunov exponents. The simpler "harmonic" flow transports more heat (produces entropy at a greater rate), whereas the more complex "chaotic" flow has a larger maximum Lyapunov exponent (corresponding to a larger rate of phase-space information loss). A linear combination of these two rates is invariant for the two flow morphologies over the entire range of Rayleigh numbers for which the flows coexist, suggesting a relation between the two rates near the onset of convective turbulence.Comment: 5 pages, 4 figure