Synthesis of Nanostructured Hydroxyapatite via Controlled Hydrothermal Route

Hydroxyapatite represents the natural inorganic component of the bone and may be considered an essential element required for the development of bone substitutes in the field of regenerative medicine. Hydroxyapatite bone substitutes own biomimetic, osteoconductive, and osteoinductive properties thanks to their chemical-physical properties and nanostructure that play a critical role for the reconstruction of calcified tissues. Controlling the structure of hydroxyapatite nanocrystals is vital for obtaining a sustained product, and it should be an advantage on the final materials suitable for bone replacement, in terms of adsorptive activity, drug delivery system, etc. Compared to other synthesis techniques, hydrothermal processing (refers to a synthesis in aqueous solution at elevated pressure and temperature, in a closed system) has the ability to precipitate the hydroxyapatite from overheated solution, regulating the rate and uniformity of nucleation, growth, and maturation, which affect size, morphology, and aggregation of the crystals. This chapter wants to provide an overview of realization of nanosized hydroxyapatite-based bioceramics (e.g., powder and 3D structures) with desired morphology of crystallites, by hydrothermal processing. In this way, some critical hydrothermal parameters fundamental on the control of the crystal shape and dimension (pH, temperature, starting precursors, etc.) are discussed

Quality of information of websites dedicated to obesity: a systematic search to promote high level of information for Internet users and professionals

Background: The Internet is increasingly used as a source of information. This study investigates with a multidimensional methodology the quality of information of websites dedicated to obesity treatment and weight-loss interventions. We compared websites in English, a language that it is used for the international scientific divulgation, and in Italian, a popular local language. Methods: Level of Evidence: Level I, systematic review search on four largely used search engines. Duplicated and unrelated websites were excluded. We checked: popularity with PageRank; technological quality with Nibbler; readability with the Flesch Reading Ease test or the Gulpease readability index; quality of information with the DISCERN scale, the JAMA benchmark criteria, and the adherence to the Health on the Net Code. Results: 63 Italian websites and 41 English websites were evaluated. English websites invested more in the technological quality especially for the marketing, experience of the user, and mobile accessibility. Both the Italian and English websites were of poor quality and readability. Conclusions: These results can inform guidelines for the improvement of health information and help Internet users to achieve a higher level of information. Users must find benefits of treatment, support to the shared decision-making, the sources used, the medical editor's supervision, and the risk of postponing the treatment

Nature-Inspired Processes and Structures: New Paradigms to Develop Highly Bioactive Devices for Hard Tissue Regeneration

Material scientists are increasingly looking to natural structures as inspiration for new-generation functional devices. Particularly in the medical field, the need to regenerate tissue defects claims, since decades, biomaterials with the ability to instruct cells toward formation and organization of new tissue. It is today increasingly accepted that biomimetics is a leading concept for biomaterials development. In fact, there is increasing evidence that the use of biomedical devices showing substantial mimicry of the composition and multi-scale structure of target native tissues have enhanced regenerative ability. As a relevant example, biomimetic materials have high potential to solve degenerative diseases affecting the musculoskeletal system, namely, bone, cartilage and articular tissues, which is of pivotal importance for most of human abilities, such as walking, running, manipulating, and chewing. In this respect, the adoption of nature-inspired processes and structures is an emerging fabrication concept, uniquely able to provide biomaterials with superior biological performance. The chapter will give an overview of the most recent results obtained in the field of hard tissue regeneration by using 3D biomaterials obtained by nature-inspired approaches. The main focus is given to porous hydroxyapatite-based ceramic or hybrid scaffolds for regeneration of bone and osteochondral tissues in neurosurgery and orthopedics

Multimode Trapped Interferometer with Ideal Bose-Einstein Condensates

We experimentally demonstrate a multi-mode interferometer comprising a Bose-Einstein condensate of $^{39}$K atoms trapped in a harmonic potential, where the interatomic interaction can be cancelled exploiting Feshbach resonances. Kapitza-Dirac diffraction from an optical lattice coherently splits the BEC in multiple momentum components equally spaced that form different interferometric paths, closed by the trapping harmonic potential. We investigate two different interferometric schemes, where the recombination pulse is applied after a full or half oscillation in the confining potential. We find that the relative amplitudes of the momentum components at the interferometer output are sensitive to external forces, through the induced displacement of the harmonic potential with respect to the optical lattice. We show how to calibrate the interferometer, fully characterize its output and discuss perspective improvements.Comment: 7 pages, 6 figure

Fully Immersive Virtual Reality-Based Cognitive Remediation for Adults with Psychosocial Disabilities: A Systematic Scoping Review of Methods Intervention Gaps and Meta-Analysis of Published Effectiveness Studies

Background: Cognitive Remediation (CR) programs are effective for the treatment of mental diseases; in recent years, Virtual Reality (VR) rehabilitation tools are increasingly used. This study aimed to systematically review and meta-analyze the published randomized controlled trials that used fully immersive VR tools for CR programs in psychiatric rehabilitation. We also wanted to map currently published CR/VR interventions, their methods components, and their evidence base, including the framework of the development intervention of CR in fully immersive VR. Methods: Level 1 of evidence. This study followed the PRISMA extension for Scoping Reviews and Systematic Review. Three electronic databases (Pubmed, Cochrane Library, Embase) were systematically searched, and studies were included if they met the eligibility criteria: only randomized clinical trials, only studies with fully immersive VR, and only CR for the adult population with mental disorders. Results: We found 4905 (database) plus 7 (manual/citation searching articles) eligible studies. According to inclusion criteria, 11 studies were finally reviewed. Of these, nine included patients with mild cognitive impairment, one with schizophrenia, and one with mild dementia. Most studies used an ecological scenario, with improvement across all cognitive domains. Although eight studies showed significant efficacy of CR/VR, the interventions’ development was poorly described, and few details were given on the interventions’ components. Conclusions: Although CR/VR seems to be effective in clinical and feasibility outcomes, the interventions and their components are not clearly described. This limits the understanding of the effectiveness and undermines their real-world implementation and the establishment of a gold standard for fully immersive VR/CR

A Recovery-Oriented Program for People with Bipolar Disorder through Virtual Reality-Based Cognitive Remediation: Results of a Feasibility Randomized Clinical Trial

Background: Cognitive impairment is a frequent consequence of bipolar disorder (BD) that is difficult to prevent and treat. In addition, the quality of the preliminary evidence on the treatment of BD through Cognitive Remediation (CR) with traditional methods is poor. This study aims to evaluate the feasibility of a CR intervention with fully immersive Virtual Reality (VR) as an additional treatment for BD and offers preliminary data on its efficacy. Methods: Feasibility randomized controlled cross-over clinical study, with experimental condition lasting three months, crossed between two groups. Experimental condition: CR fully immersive VR recovery-oriented program plus conventional care; Control condition: conventional care. The control group began the experimental condition after a three months period of conventional care (waiting list). After the randomization of 50 people with BD diagnosis, the final sample consists of 39 participants in the experimental condition and 25 in the control condition because of dropouts. Results: Acceptability and tolerability of the intervention were good. Compared to the waitlist group, the experimental group reported a significant improvement regarding cognitive functions (memory: p = 0.003; attention: p = 0.002, verbal fluency: p = 0.010, executive function: p = 0.003), depressive symptoms (p = 0.030), emotional awareness (p = 0.007) and biological rhythms (p = 0.029). Conclusions: The results are preliminary and cannot be considered exhaustive due to the small sample size. However, the evidence of efficacy, together with the good acceptability of the intervention, is of interest. These results suggest the need to conduct studies with larger samples that can confirm this data. Trial registration: ClinicalTrialsgov NCT05070065, registered in September 202

Non-neuronal TRPA1 encodes mechanical allodynia associated with neurogenic inflammation and partial nerve injury in rats

Background and purpose: The pro-algesic transient receptor potential ankyrin 1 (TRPA1) channel, expressed by a subpopulation of primary sensory neurons, has been implicated in various pain models in mice. However, evidence in rats indicates that TRPA1 conveys nociceptive signals elicited by channel activators, but not those associated with tissue inflammation or nerve injury. Here, in rats, we explored the TRPA1 role in mechanical allodynia associated with stimulation of peptidergic primary sensory neurons (neurogenic inflammation) and moderate (partial sciatic nerve ligation, pSNL) or severe (chronic constriction injury, CCI) sciatic nerve injury. Experimental approach: Acute nociception and mechanical hypersensitivity associated with neurogenic inflammation and sciatic nerve injury (pSNL and CCI) were investigated in rats with TRPA1 pharmacological antagonism or genetic silencing. TRPA1 presence and function were analysed in cultured rat Schwann cells. Key results: Hind paw mechanical allodynia (HPMA), but not acute nociception, evoked by local injection of capsaicin or allyl isothiocyanate, the TRP vanilloid 1 (TRPV1) or the TRPA1 activators was mediated by CGRP released from peripheral sensory nerve terminals. CGRP-evoked HPMA was sustained by a ROS-dependent TRPA1 activation, probably in Schwann cells. HPMA evoked by pSNL, but not that evoked by CCI, was mediated by ROS and TRPA1 without the involvement of CGRP. Conclusions and implications: As found in mice, TRPA1 mediates mechanical allodynia associated with neurogenic inflammation and moderate nerve injury in rats. The channel contribution to mechanical hypersensitivity is a common feature in rodents and might be explored in humans

Enhancement of the Biological and Mechanical Performances of Sintered Hydroxyapatite by Multiple Ions Doping

In the present work, hydroxyapatite (HA) nanoparticles doped with Mg2+, Sr2+, and Zn2+ ions are developed by wet neutralization method and then sintered at 1,250°C to obtain bulk consolidated materials. Physicochemical and microstructural analyses show that the presence of doping ions in the HA structure induced the formation of βTCP as secondary phase, during the sintering process, and we found that this effect is depending on the stability of the various doping ions in the hydroxyapatite lattice itself. We also found that the formation of βTCP as secondary phase, in turn, confines the grain growth of HA induced by the high-temperature sintering process, thus leading to a strong increase of the flexural strength of the bulk materials, according to Hall-Petch-like law. Furthermore, we found that the doping ions enter also in the structure of the βTCP phase; besides the grain growth confinement, also the solubility and ion release ability of the final materials were enhanced. In addition to ameliorate the mechanical performance, the described phenomena also activate multiple biofunctionalities: (i) ability to upregulate various genes involved in the osteogenesis, as obtained by human adipose stem cells culture and evaluated by array technology; (ii) enhanced resistance to the adhesion and proliferation of Gram+ and Gram– bacterial strains. Hence, our results open a perspective for the use of sintered multiple ion-doped HA to develop ceramic biodevices, such as plates, screws, or other osteosynthesis media, with enhanced strength, osteointegrability, and the ability to prevent post-surgical infections

Mutually exclusive redox forms of HMGB1 promote cell recruitment or proinflammatory cytokine release

Tissue damage causes inflammation, by recruiting leukocytes and activating them to release proinflammatory mediators. We show that high-mobility group box 1 protein (HMGB1) orchestrates both processes by switching among mutually exclusive redox states. Reduced cysteines make HMGB1 a chemoattractant, whereas a disulfide bond makes it a proinflammatory cytokine and further cysteine oxidation to sulfonates by reactive oxygen species abrogates both activities. We show that leukocyte recruitment and activation can be separated. A nonoxidizable HMGB1 mutant in which serines replace all cysteines (3S- HMGB1) does not promote cytokine production, but is more effective than wild-type HMGB1 in recruiting leukocytes in vivo. BoxA, a HMGB1 inhibitor, interferes with leukocyte recruitment but not with activation. We detected the different redox forms of HMGB1 ex vivo within injured muscle. HMGB1 is completely reduced at first and disulfide-bonded later. Thus, HMGB1 orchestrates both key events in sterile inflammation, leukocyte recruitment and their induction to secrete inflammatory cytokines, by adopting mutually exclusive redox states