RESUMEN
Functional neuroimaging methods like fMRI and PET are vital in neuroscience research, but require that subjects remain still throughout the scan. In animal research, anesthetic agents are typically applied to facilitate the acquisition of high-quality data with minimal motion artifact. However, anesthesia can have profound effects on brain metabolism, selectively altering dynamic neural networks and confounding the acquired data. To overcome the challenge, we have developed a novel head fixation device designed to support awake rat brain imaging. A validation experiment demonstrated that the device effectively minimizes animal motion throughout the scan, with mean absolute displacement and mean relative displacement of 0.0256 (SD: 0.001) and 0.009 (SD: 0.002), across eight evaluated subjects throughout fMRI image acquisition (total scanning time per subject: 31 min, 12 s). Furthermore, the awake scans did not induce discernable stress to the animals, with stable physiological parameters throughout the scan (Mean HR: 344, Mean RR: 56, Mean SpO2: 94 %) and unaltered serum corticosterone levels (p = 0.159). In conclusion, the device presented in this paper offers an effective and safe method of acquiring functional brain images in rats, allowing researchers to minimize the confounding effects of anesthetic use.
Asunto(s)
Anestésicos , Vigilia , Humanos , Ratas , Animales , Vigilia/fisiología , Encéfalo/fisiología , Cabeza , Neuroimagen/métodos , Imagen por Resonancia Magnética/métodos , Anestésicos/farmacologíaRESUMEN
Bone metastasis at an advanced disease stage is common in most solid tumors and is untreatable. Overexpression of receptor activator of nuclear factor κB ligand (RANKL) in tumor-bone marrow microenvironment drives a vicious cycle of tumor progression and bone resorption. Biodegradable nanoparticles (NPs), designed to localize in the tumor tissue in bone marrow, were evaluated in a prostate cancer model of bone metastasis. The combination treatment, encapsulating docetaxel, an anticancer drug (TXT-NPs), and Denosumab, a monoclonal antibody that binds to RANKL (DNmb-NPs), administered intravenously regressed the tumor completely, preventing bone resorption, without causing any mortality. With TXT-NPs alone treatment, after an initial regression, the tumor relapsed and acquired resistance, whereas DNmb-NPs alone treatment was ineffective. Only in the combination treatment, RANKL was not detected in the tumor tibia, thus negating its role in tumor progression and bone resorption. The combination treatment was determined to be safe as the vital organ tissue showed no increase in inflammatory cytokine or the liver ALT/AST levels, and animals gained weight. Overall, dual drug treatment acted synergistically to modulate the tumor-bone microenvironment with encapsulation enhancing their therapeutic potency to achieve tumor regression.
Asunto(s)
Neoplasias Óseas , Resorción Ósea , Nanopartículas , Masculino , Animales , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/secundario , Resorción Ósea/prevención & control , Combinación de Medicamentos , Microambiente TumoralRESUMEN
Amniotic membranes are known to be rich in growth factors, cytokines, and matrix proteins, which can help support wound closure and may improve patient outcomes in foot and ankle surgical interventions. In this Institutional Review Board (IRB) approved clinical study, 21 consecutive patients undergoing lower extremity soft tissue and bone reconstruction surgery received dehydrated human amnion and chorion allograft (dHACA) placed as a covering over the deep layers of the surgical wound during closure. Wound healing complications were assessed and American Orthopaedic Foot and Ankle Society (AOFAS) scores were compiled from over a 1-year follow-up period. Summary statistics were calculated for average pain, function, and alignment. The average overall AOFAS pre-treatment score was 35.8 ± 23.0 and the post-treatment score significantly improved to 87.5 ± 6.4 (P = 3.7 × 10-10 ). The pain-score improved from pre-treatment at 10.0 ± 11.0 to post-treatment at 36.7 ± 4.8 (P = 5.0 × 10-5 ). The pre-treatment function score was 18.7 ± 12.9 and at post-treatment increased to 38.5 ± 5.7 (P = 5.8 × 10-5 ). Lastly, the alignment score at pre-treatment was 7.1 ± 4.4 and at post-treatment was 12.4 ± 2.6 (P = .001). These improvements in functional scores were accompanied with clinical observations of reduced surgical complications including a lack of wound dehisance in the cohort. These clinical findings suggest that the application of aseptically processed dHACA may reduce wound complications and as such may aide in clinical improvements in foot and ankle surgical interventions however a larger comparative trial should be considered to validate these initial findings.