Efficacy of Stanozolol on bone regeneration: in vitro and in vivo study

La ricerca di nuove strategie per la rigenerazione ossea rappresenta un focus di interesse centrale per migliorare la gestione di casi clinici complessi nell’ambito della chirurgia orale e maxillo-facciale. Uno degli approcci più utilizzati in tale contesto si basa sull’utilizzo di molecole con proprietà osteoinduttive e molte sostanze sono state fino ad oggi sperimentate. E’ noto in letteratura che gli androgeni svolgono un ruolo chiave nella regolazione della morfogenesi ossea e nel mantenimento della sua omeostasi durante il corso della vita. Questo lavoro di tesi nasce dall’ipotesi che la somministrazione locale di tali ormoni, eventualmente combinata a materiali da innesto, possa favorire la guarigione di difetti ossei. Stando a questa premessa, sono stati valutati gli effetti dello steroide sintetico Stanozololo sulla rigenerazione ossea in diversi settings sperimentali. La tesi è strutturata secondo un percorso che segue le fasi della ricerca, attraverso sperimentazioni in vitro e in vivo; ogni capitolo può essere approcciato come uno studio a sé stante, corrispondente ad una determinata tappa dell’iter sperimentale. Sulla base di questi intenti, viene fornito inizialmente un quadro d’insieme circa gli effetti degli androgeni sull’osso. A seguire, è presentata una sperimentazione in vitro nella linea cellulare SaOS-2. Infine, è proposta un’innovativa metodologia di analisi per lo studio della rigenerazione ossea nel modello di ratto, ove viene testata la somministrazione locale di Stanozololo combinato a materiale da innesto.

Gene therapy strategies for the treatment of spinal cord injury

Spinal cord injury is a complex pathology often resulting in functional impairment and paralysis. Gene therapy has emerged as a possible solution to the problems of limited neural tissue regeneration through the administration of factors promoting axonal growth, while also offering long-term local delivery of therapeutic molecules at the injury site. Of note, gene therapy is our response to the requirements of neural and glial cells following spinal cord injury, providing, in a time-dependent manner, growth substances for axonal regeneration and eliminating axonal growth inhibitors. Herein, we explore different gene therapy strategies, including targeting gene expression to modulate the presence of neurotrophic growth or survival factors and increase neural tissue plasticity. Special attention is given to describing advances in viral and non-viral gene delivery systems, as well as the available routes of gene delivery. Finally, we discuss the future of combinatorial gene therapies and give consideration to the implementation of gene therapy in humans. © 2014 Future Science Ltd.

Development and regeneration of neuronal circuits in the vertebrate retina

Thesis (Ph.D.)--University of Washington, 2016-08

Development of a 1-D Catalyzed Diesel Particulate Filter Model for Simulation of the Performance and the Oxidation of Particulate Matter and Nitrogen Oxides Using Passive Oxidation and Active Regeneration Engine Experimental Data

Back-pressure on a diesel engine equipped with an aftertreatment system is a function of the pressure drop across the individual components of the aftertreatment system, typically, a diesel oxidation catalyst (DOC), catalyzed particulate filter (CPF) and selective catalytic reduction (SCR) catalyst. Pressure drop across the CPF is a function of the mass flow rate and the temperature of the exhaust flowing through it as well as the mass of particulate matter (PM) retained in the substrate wall and the cake layer that forms on the substrate wall. Therefore, in order to control the back-pressure on the engine at low levels and to minimize the fuel consumption, it is important to control the PM mass retained in the CPF. Chemical reactions involving the oxidation of PM under passive oxidation and active regeneration conditions can be utilized with computer numerical models in the engine control unit (ECU) to control the pressure drop across the CPF. Hence, understanding and predicting the filtration and oxidation of PM in the CPF and the effect of these processes on the pressure drop across the CPF are necessary for developing control strategies for the aftertreatment system to reduce back-pressure on the engine and in turn fuel consumption particularly from active regeneration. Numerical modeling of CPF's has been proven to reduce development time and the cost of aftertreatment systems used in production as well as to facilitate understanding of the internal processes occurring during different operating conditions that the particulate filter is subjected to. A numerical model of the CPF was developed in this research work which was calibrated to data from passive oxidation and active regeneration experiments in order to determine the kinetic parameters for oxidation of PM and nitrogen oxides along with the model filtration parameters. The research results include the comparison between the model and the experimental data for pressure drop, PM mass retained, filtration efficiencies, CPF outlet gas temperatures and species (NO2) concentrations out of the CPF. Comparisons of PM oxidation reaction rates obtained from the model calibration to the data from the experiments for ULSD, 10 and 20% biodiesel-blended fuels are presented.

Plant/Leaf traits and adaptive strategies of Cistus species to Mediterranean drought and insolation in southern Portugal

The effects of climate change can result in dramatic consequences in specific ecosystems such as montados that are seriously threatened by the absence of cork and holm oak (Quercus suber and Q. rotundifolia) natural regeneration. Shrubs of the genus Cistus, which are among the most important elements of encroached montados, seem to promote soil rehabilitation and enhance oak regeneration (Simões et al. 2009). In this context, we compared the life strategies and evaluated the potential ability of Cistus species to adapt to the increasing drought expected for the Mediterranean region, and thus their role on the sustainability of cork oak montados.

To Evaluate the Synergistic Effect of Different Crosslinking Strategies on Collagen Derivatives to Develop Funcional Biomimetic Scaffolds

The preliminary objective of this work was to study how the effect of different crosslinking methodologies can functionally modify various characteristics of biological macromolecules relevant for scaffold development in bone tissue engineering. The research study was classified and studied in three different phases: (i) different crosslinking strategies in gelatin functionalization, (ii) ribose mediated crosslinking in collagen-hydroxyapatite scaffold (iii) different crosslinking mechanisms in functional modification of bone-like scaffold. The obtained results were highly positive in all the three investigated studies. Though the core aim of this research was to explore the available crosslinking strategies in different biological macromolecules, the present study generated significant findings, largely contributing to provide optimum solutions in understanding how the crosslinking density can fine-tune the overall performance of a scaffold, relevant for its functioning in vivo. In particular, this study demonstrated that different crosslinkers at different conditions (pH and temperature) can modify the functional properties of the scaffolds differently, therefore this optimization strategies on these crosslinkers as obtained from this study results will help material scientists in the design and development of bioactive hybrid biomaterials for hard tissue regeneration.

Novel biomaterials for regeneration of periapical bone defects in endodontic and implant therapy

Endodontic-related periapical bone defects are a common occurrence in the global populations. Considering the number of root canal treatments performed annually, new strategies and new biomaterials for the management of these bone defects will be important and highlight the need for continued research and development in endodontic field. The present PhD thesis have several objectives and is divided into two main sections: one focused on in vitro and laboratory research and the other on clinical in vivo investigations. The first part, focused on laboratory and in vitro research, investigated 2 main topics: • the microbial communities of apical periodontitis to evaluate the predominant bacterial using 16sr DNA-targeted Nanopore sequencing; • the physical-chemical properties of innovative premixed calcium-silicate based bioceramic sealers for endodontic therapy; The second part, focused on in vivo clinical studies, investigated 2 main topics: • the clinical application of premixed calcium-silicate-based sealers. Ethical committee approval was obtained in 2 separate in vivo studies. The first one is a prospective cohort study with a two-year follow-up where the test group was compared with a control group (considered the gold standard). The second is a pilot prospective cohort study with a 12-month follow-up which set the foundation for a subsequent randomized investigation. Thanks to these investigations, we validated a new technique that innovatively associates a warm obturation technique with calcium-silicate-based sealers. Historically, these sealers were only used with cold techniques. This investigation highlights the possibility for wider utilization and improvements in endodontic techniques. • The outcome of 2 different types of implants characterized by different surface treatments and placed with different techniques. The marginal bone level and periodontal parameters were evaluated with a follow-up of 4 and 10 years. This Ph.D thesis is based on a compilation of published papers I have done during my three-year PhD program.

[strategies For Integration Of Health Care Practices And Sanitary Surveillance In The Context Of The Implementation Of Rede Cegonha - A Brazilian Mother And Infant Health Care Network].

Mother and infant mortality has been the scope of analysis throughout the history of public health in Brazil and various strategies to tackle the issue have been proposed to date. The Ministry of Health has been working on this and the Rede Cegonha strategy is the most recent policy in this context. Given the principle of comprehensive health care and the structure of the Unified Health System in care networks, it is necessary to ensure the integration of health care practices, among which are the sanitary surveillance actions (SSA). Considering that the integration of health care practices and SSA can contribute to reduce mother and infant mortality rates, this article is a result of qualitative research that analyzed the integration of these actions in four cities in the State of São Paulo/Brazil: Campinas, Indaiatuba, Jaguariúna and Santa Bárbara D'Oeste. The research was conducted through interviews with SSA and maternal health managers, and the data were evaluated using thematic analysis. The results converge with other studies, identifying the isolation of health care practices and SSA. The insertion of SSA in collectively-managed areas appears to be a potential strategy for health planning and implementation of actions in the context under scrutiny.

Mesenchymal Stem Cells Engrafted In A Fibrin Scaffold Stimulate Schwann Cell Reactivity And Axonal Regeneration Following Sciatic Nerve Tubulization.

The present study investigated the effectiveness of mesenchymal stem cells (MSCs) associated with a fibrin scaffold (FS) for the peripheral regenerative process after nerve tubulization. Adult female Lewis rats received a unilateral sciatic nerve transection followed by repair with a polycaprolactone (PCL)-based tubular prosthesis. Sixty days after injury, the regenerated nerves were studied by immunohistochemistry. Anti-p75NTR immunostaining was used to investigate the reactivity of the MSCs. Basal labeling, which was upregulated during the regenerative process, was detected in uninjured nerves and was significantly greater in the MSC-treated group. The presence of GFP-positive MSCs was detected in the nerves, indicating the long term survival of such cells. Moreover, there was co-localization between MSCs and BNDF immunoreactivity, showing a possible mechanism by which MSCs improve the reactivity of SCs. Myelinated axon counting and morphometric analyses showed that MSC engrafting led to a higher degree of fiber compaction combined with a trend of increased myelin sheath thickness, when compared with other groups. The functional result of MSC engrafting was that the animals showed higher motor function recovery at the seventh and eighth week after lesion. The findings herein show that MSC+FS therapy improves the nerve regeneration process by positively modulating the reactivity of SCs.

Effect Of Low-level Laser Therapy (lllt) On Peripheral Nerve Regeneration Using Fibrin Glue Derived From Snake Venom.

The purpose of this study was to assess whether the adhesive permits the collateral repair of axons originating from a vagus nerve to the interior of a sural nerve graft, and whether low-level laser therapy (LLLT) assists in the regeneration process. Study sample consisted of 32 rats randomly separated into three groups: Control Group (CG; n=8), from which the intact sural nerve was collected; Experimental Group (EG; n=12), in which one of the ends of the sural nerve graft was coapted to the vagus nerve using the fibrin glue; and Experimental Group Laser (EGL; n=12), in which the animals underwent the same procedures as those in EG with the addition of LLLT. Ten weeks after surgery, the animals were euthanized. Morphological analysis by means of optical and electron microscopy, and morphometry of the regenerated fibers were employed to evaluate the results. Collateral regeneration of axons was observed from the vagus nerve to the interior of the autologous graft in EG and EGL, and in CG all dimensions measured were greater and presented a significant difference in relation to EG and EGL, except for the area and thickness of the myelin sheath, that showed significant difference only in relation to the EG. The present study demonstrated that the fibrin glue makes axonal regeneration feasible and is an efficient method to recover injured peripheral nerves, and the use of low-level laser therapy enhances nerve regeneration.

[strategies For Tackling Absenteeism In Dental Appointments In The Family Health Units Of A Large Municipality: Action Research].

The aim of this study was to analyze the reasons for missed appointments in dental Family Health Units (FHU) and implement strategies to reduce same through action research. This is a study conducted in 12 FHUs in Piracicaba in the State of São Paulo from January, 1 to December, 31 2010. The sample was composed of 385 users of these health units who were interviewed over the phone and asked about the reasons for missing dental appointments, as well as 12 dentists and 12 nurses. Two workshops were staged with professionals: the first to assess the data collected in interviews and develop strategy, and the second for evaluation after 4 months. The primary cause for missed appointments was the opening hours of the units coinciding with the work schedule of the users. Among the strategies suggested were lectures on oral health, ongoing education in team meetings, training of Community Health Agents, participation in therapeutic groups and partnerships between Oral Health Teams and the social infrastructure of the community. The adoption of the single medical record was the strategy proposed by professionals. The strategies implemented led to a 66.6% reduction in missed appointments by the units and the motivating nature of the workshops elicited critical reflection to redirect health practices.

Quality Of Life Of Coronary Artery Disease Patients After The Implementation Of Planning Strategies For Medication Adherence.

to compare the general and specific health-related quality of life (HRQoL) between the Intervention (IG) and Control (CG) groups of coronary artery disease patients after the implementation of Action Planning and Coping Planning strategies for medication adherence and to verify the relationship between adherence and HRQoL. this was a controlled and randomized study. the sample (n=115) was randomized into two groups, IG (n=59) and CG (n=56). Measures of medication adherence and general and specific HRQoL were obtained in the baseline and after two months of monitoring. the findings showed that the combination of intervention strategies - Action Planning and Coping Planning for medication adherence did not affect the HRQoL of coronary artery disease patients in outpatient monitoring.

Trends and strategies of ozone application in environmental problems

Efforts presented by the scientific community in recent years towards the development of numerous green chemical processes and wastewater treatment technologies are presented and discussed. In the light of these approaches, environmentally friendly technologies, as well as the key role played by the well-known advanced oxidation processes, are discussed, giving special attention to the ones comprising ozone applications. Fundamentals and applied aspects dealing with ozone technology and its application are also presented.

Mixed rain forest in southeastern Brazil: tree species regeneration and floristic relationships in a remaining stretch of forest near the city of Itaberá, Brazil

The aim of this work was to evaluate the floristic composition, richness, and diversity of the upper and lower strata of a stretch of mixed rain forest near the city of Itaberá, in southeastern Brazil. We also investigated the differences between this conservation area and other stretches of mixed rain forest in southern and southeastern Brazil, as well as other nearby forest formations, in terms of their floristic relationships. For our survey of the upper stratum (diameter at breast height [DBH] > 15 cm), we established 50 permanent plots of 10 × 20 m. Within each of those plots, we designated five, randomly located, 1 × 1 m subplots, in order to survey the lower stratum (total height > 30 cm and DBH < 15 cm). In the upper stratum, we sampled 1429 trees and shrubs, belonging to 134 species, 93 genera, and 47 families. In the lower stratum, we sampled 758 trees and shrubs, belonging to 93 species, 66 genera, and 39 families. In our floristic and phytosociological surveys, we recorded 177 species, belonging to 106 genera and 52 families. The Shannon Diversity Index was 4.12 and 3.5 for the upper and lower strata, respectively. Cluster analysis indicated that nearby forest formations had the strongest floristic influence on the study area, which was therefore distinct from other mixed rain forests in southern Brazil and in the Serra da Mantiqueira mountain range.

Tissue culture of Cecropia glaziovii Sneth (urticaceae): vegetative micropropagation and plant regeneration from callus

Cecropia glaziovii is a tree with used in Brazilian popular medicine. Methods allowing the clonal propagation of this species are of great interest for superior genotype multiplication and perpetuation. For this reason, we examined the effect of different culture media and different types of explants on adventitious shoot regeneration from callus and buds of C. glaziovii. Leaves, petioles and stipules obtained from aseptically grown seedlings or from pre-sterilized plants were used to initiate cultures. Adventitious shoot regeneration was achieved when apical and axillary buds were inoculated on gelled Murashige & Skoog (MS) medium supplemented with 6-benzylaminopurine alone (BAP) (1.0, 5.0 or 10.0 mg L-1) or combined with -naphthalene acetic acid (NAA) (1.0 or 2.0 mg L-1), after 40 days of culture. Best callus production was obtained after 30 days of petioles' culture on gelled MS medium with 2,4 dichlorophenoxyacetic acid (2,4-D) (5.0 mg L-1) combined with BAP (1.0 mg L-1). Successful shoot regeneration from callus was achieved when MS medium supplemented with zeatin (ZEA) (0.1 mg L-1) alone or combined with 2,4-D (1.0 or 5.0 mg L-1) was inoculated with friable callus obtained from petioles. All shoots were rooted by inoculation on MS medium supplemented with indole-3-acetic acid (IAA) (1.0 mg L-1). Rooted plants transferred to potting soil were successfully established. All in vitro regenerated plantlets showed to be normal, without morphological variations, being also identical to the source plant. Our study has shown that C. glaziovii can be propagated by tissue culture methods, allowing large scale multiplication of superior plants for pharmacological purposes.