Hamstring muscle injuries are prevalent in sports, presenting substantial hurdles for athletes and teams due to their high recurrence rates and prolonged recovery periods. The biceps femoris (BF) ...muscle is frequently implicated in these injuries, with notably high recurrence rates, particularly at the distal musculotendinous T-junction (DMTJ), where half of BF reinjuries occur. This paper presents a case study of a 31-year-old female long-distance athlete with a history of DMTJ rupture, shedding light on the intricacies associated with hamstring injuries. The case underscores the challenges in accurately interpreting imaging findings, reinforcing the need for clinical-imaging correlation and exploration of lesion mechanisms to achieve an accurate diagnosis, optimize outcomes, and facilitate a safe return to sport.
The objective was to synthesize and characterize fine polycaprolactone (PCL) fibers associated with a new 58S bioglass obtained by the precipitated sol-gel route, produced by the electrospinning ...process in order to incorporate therapeutic ions (Mg and Li). In PCL/acetone solutions were added 7% pure bioglass, bioglass doped with Mg(NO
)
and Li
CO
and were subjected to electrospinning process. The fibers obtained were characterized morphologically, chemically and biologically. The results showed the presence of fine fibers at the nanometric scale and with diameters ranging from 0.67 to 1.92 μm among groups. Groups containing bioglass showed particles both inside and on the surface of the fibers. The components of the polymer, bioglass and therapeutic ions were present in the fibers produced. The produced fibers showed cell viability and induced the formation of mineralization nodules. It was observed the applicability of that methodology in making an improved biomaterial, which adds the osteoinductive properties of the bioglass to PCL and to those of therapeutic ions, applicable to guided bone regeneration.
This work studied the influence of two sol-gel synthesis routes in obtaining a bioactive glass-ceramic derived from the 45S5 composition: a polymeric and a colloidal route. The main difference ...between the routes is in the silica precursor employed. The tetraethyl orthosilicate metal alkoxide (Si(OC2H5)4 - TEOS) is used in polymeric route and the silicic acid (H4SiO4) was used in the colloidal route. The synthesized xerogels were calcined at different temperatures to eliminate undesirable compounds and to verify the crystallization behavior. Afterwards, the calcined xerogels were submitted to in vitro bioactivity assay. The samples were also characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and laser diffraction. After calcination, the glass-ceramics obtained by the colloidal route showed greater number of bioactive phases and, consequently, of NBO bonds. The larger amount of NBO bonds resulted in a higher bioactivity of the materials synthesized by the colloidal route. In addition, the long hydrolysis step of the metal alkoxides was eliminated with colloidal synthesis. This allowed a significant reduction in the total synthesis time from 13 days to 24 h. To the best of our knowledge, this seems to be the first time this colloidal route has been employed in the synthesis of bioglass 45S5.
Different agents have been proposed to prevent the progression of acid induced dental substance losses, which are called erosive tooth wear (ETW), such as fluorides, calcium, and phosphate-based ...products; however, there is a need for a further increase in efficacy. Recently, the ability of polymers to interact with the tooth surface, forming acid resistant films, has come into the focus of research; nevertheless, there is still the need for a better understanding of their mode of action. Thus, this article provides an overview of the chemical structure of polymers, their mode of action, as well as the effect of their incorporation into oral care products, acid beverages, and antacid formulations, targeting the prevention of ETW. Recent evidence indicates that this may be a promising approach, however, additional studies are needed to confirm their efficacy under more relevant clinical conditions that consider salivary parameters such as flow rate, composition, and clearance. The standardization of methodological procedures such as acid challenge, treatment duration, and combination with fluorides is necessary to allow further comparisons between studies. In conclusion, film-forming polymers may be a promising cost-effective approach to prevent and control erosive demineralization of the dental hard tissue.
The integration of biomaterials in tissue regeneration has been showing effectiveness in the treatment of diseases related to bone structure and tissue repair. Membranes have aroused interest due to ...their ease of manufacture, variation in composition, and the structure of the biomaterial. The incorporation of bioactive glass (BG) increases bioactivity, and when doped with therapeutic ions, changes in the physical-chemical composition of the biomaterial are expected to enhance its biological effect. This study aimed to produce polycaprolactone (PCL) membranes incorporated with 58S bioactive glass, doped with Zinc (Zn) by the electrospinning technique, and evaluate the influence of this biomaterial in the activity and differentiation of mesenchymal stem cells. The BG was produced by using the sol-gel process; next, before the PCL preparation, the BG was doped with zinc in a solution. Then, PCL solutions were prepared with 7% by weight of BG and doped with 10% ZnCl
2
. Afterward, the electrospinning process was carried out using the fixed parameters: 2mLh-1 flow rate, 10kV voltage, and 12cm distance. Before the biological assays, the chemical elements present in the fibers were evaluated by energy dispersion X-ray spectroscopy (EDS), and the mapping technique. The morphology of the biomaterial and the diameter of fibers were analyzed by scanning electron microscopy (SEM), and the hydrophilicity of the membranes was evaluated by the contact angle technique. The in vitro tests consisted of cell plating with mesenchymal stem cells (MSC’s), previously obtained from rat femurs, at a density of 1x10
4
per well that contained three different groups: a) P: mesenchymal stem cells plated with PCL; b) PB: mesenchymal stem cells plated with the composite of PCL / BG; c) PBZ: mesenchymal stem cells plated with the Zn doped PCL / BG composite. To evaluate the influence of the biomaterial on osteoblastic activity and differentiation, osteogenic and non-osteogenic media were used in tests of cell viability (MTT assay), total protein content, alkaline phosphatase activity (ALP), and mineralization nodules. The analysis by SEM proved that the electrospinning technique was efficient for producing fibers incorporated with bioactive glass, and EDS and the mapping technique confirmed the chemical components of each group of fibers, including the doped zinc in the bioactive glass. The analysis of fibers diameter showed that P and PBZ had presented fibers with a larger diameter than the PB group, and the contact angle technique showed an increase in the hydrophilicity of the group containing doped Zinc when compared to the other groups analyzed. The MTT assay confirmed that the membranes weren´t cytotoxic and allowed cell viability, total protein content showed that all the groups had cell activity, with a statistically significant difference between the groups (p<0,05). Even with no statistically significant difference, osteogenesis was proved by ALP activity and the formation of mineralization nodules. Based on the results, the PCL membranes incorporated with 58S bioactive glass doped with zinc have shown promise in tissue engineering for use in bone tissue regeneration.
This study reports a novel green chemistry approach to assemble copper‐nanowires/reduced‐graphene‐oxide hybrid coatings onto inorganic and organic supports. Such films are robust and combine sheet ...resistances (<30 Ω sq−1) and transparencies in the visible region (transmittance > 70%) that are rivalling those of indium–tin oxide. These electrodes are suitable for flexible electronic applications as they show a sheet resistance change of <4% after 10 000 bending cycles at a bending radius of 1.0 cm, when supported on polyethylene terephthalate foils. Significantly, the wet‐chemistry method involves the preparation of dispersions in environmentally friendly solvents and avoids the use of harmful reagents. Such inks are processed at room temperature on a wide variety of surfaces by spray coating. As a proof‐of‐concept, this study demonstrates the successful use of such coatings as electrodes in high‐performance electrochromic devices. The robustness of the electrodes is demonstrated by performing several tens of thousands of cycles of device operation. These unique conducting coatings hold potential for being exploited as transparent electrodes in numerous optoelectronic applications such as solar cells, light‐emitting diodes, and displays.
Hybrid spray‐coated films of copper nanowires/reduced graphene oxide are obtained by simultaneous reduction in water using NaBH4 at room temperature. Such robust films display high conductivity, good transparency, and flexibility, and can be deposited onto different substrates. Their application as working electrodes in an electrochromic device is demonstrated.
Super hydrophilic scaffolds of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with 3 wt % of acetylated (CNC-Ac) and PEGylated (CNC-PEG) cellulose nanocrystals (CNC) were prepared. PHBV, ...PHBV/CNC-Ac, and PHBV/CNC-PEG scaffolds were characterized with respect to their morphology by scanning electron microscopy (SEM) and X-ray microtomography. The crystallinity was evaluated by differential scanning calorimetry (DSC) and the mechanical properties by uniaxial compression tests. The presence of residual solvent was identified by gas chromatography (GC), wettability measured by static contact angle and aqueous adsorption by gravimetry. All the scaffolds showed porous morphology, being that, for neat PHBV the morphology was more regular with oriented pores. The porosity was reduced by 26% with the introduction of CNC-Ac and CNC-PEG, and the compression modulus increased by 25% and 72% for PHBV/CNC-Ac and PHBV/CNC-PEG scaffolds, respectively, compared to neat PHBV. Even with lower porosities, PHBV/CNC-Ac and PHBV/CNC-PEG adsorbed 16% and 67% more water than PHBV scaffold, following the intraparticle diffusion model for all the samples. No residual solvents were found and the crystallinity was slightly increased upon addition of CNC-Ac and CNC-PEG. Therefore, the addition of CNC-Ac and CNC-PEG can improve both compressive modulus and water uptake, turning PHBV nanocomposite scaffolds suitable for tissue engineering applications.
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•Super hydrophilic scaffolds of PHBV with functionalized cellulose nanocrystals were produced.•The addition of functionalized cellulose nanocrystals enhanced not only the water uptake, but also the compression modulus.•For all the conditions, porous and with no residual solvent scaffolds were obtained.•Scaffolds with reinforced mechanical and improved water adsorption properties were described.
The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes.
Cattle lameness remains a significant concern, causing ...economic losses and compromising animal welfare. Claw horn lesions have been identified as a major cause of lameness in dairy cows, but their correlation with high-energy diets and ruminal acidosis remains unclear. Hence, the primary objective of this study was to assess the effects of a high-starch diet and a conventional diet on the rumen environment, acute-phase proteins, and metabolic alterations, with a particular focus on insulin resistance and the consequent implications for the histology of the hooves in Holstein steers. A total of 16 animals were divided into the high-starch (HS; 37% starch) and conventional (CON; 16.8% starch) groups. Glucose tolerance tests (GTT), blood analyses, rumen fluid analyses, and histological evaluations of the hoof tissue were conducted over a 102-d experimental period. The HS group showed a lower ruminal pH than the CON group, and with values indicating SARA. The plasma glucose and IGF-1 concentrations were higher in the HS group, suggesting an anabolic state. Both groups exhibited an increase in the insulin area under the curve (AUC) after the GTT on d 102. Histological analysis of the hooves showed a reduction in the length and width of the epidermal lamella in both groups. We found a significant negative correlation between the insulin AUC and the length and width of the epidermal lamella. Because both groups were similarly affected, the hypothesis that histological alterations were caused by the experimental diets still needs confirmation. Additionally, the development of SARA was not essential for the observed histological changes in the hoof. Further studies are warranted to thoroughly investigate the role of insulin and IGF-1 imbalances in claw health.
This paper reports the development of new ZnO/carbon xerogel composites (XZn w) for photocatalytic applications. The use of black wattle tannin as a precursor to the carbon xerogel aimed at reducing ...costs and environmental impacts. The composites were characterized by diffuse reflectance spectroscopy (DRS), BET surface area, scanning electron microscopy (FEG-SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS), infrared spectroscopy (IR), and X-ray diffraction (XRD). The photocatalytic performance of the materials was evaluated in the decomposition process of methylene blue, a known toxic pollutant. The impacts of the catalyst dosage and calcination temperature on the photocatalytic process were also examined systematically. The X-ray profiles of the XZn w evidenced the existence of the hexagonal structure of the zinc oxide (wurtzite) in the composites. The XPS and XRD analyses confirmed the incorporation of carbon in the zinc oxide crystalline structure. The higher carbon content resulted in a larger surface area. All composites presented the ability to absorb radiation in less energetic wavelengths, contrary to pure zinc oxide that only absorbs radiation of wavelengths below 420 nm. The optimal dosage and calcination temperature were found to be 0.2 g L−1 and 300 °C. All the developed composites displayed significant photocatalytic activities in the decomposition of methylene blue under both visible and solar light. The composites had superior photocatalytic efficiency under visible light when compared to pure zinc oxide. The XZn 0.5 presented the best degradation efficiency under visible radiation. All materials presented similar photocatalytic responses under solar light, evidencing the synergy between the carbon xerogel and the zinc oxide. The photocatalytic mechanism was evaluated by trapping experiments to be mainly controlled by the electron vacancies that are generated during the photoexcitation of the composites.
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