Tolstruplyon9190
Three-dimensional tissue culture, and particularly spheroid models, have recently been recognized as highly relevant in drug screening, toxicity assessment and tissue engineering due to their superior complexity and heterogeneity akin to the in vivo microenvironment. However, limitations in size control, shape reproducibility and long maturation times hinder their full applicability. Here, we report a spheroid formation technique based on the magnetic aggregation of cells with internalized magnetic nanoparticles. The method yields magnetic spheroids with high sphericity and allows fine-tuning the final spheroid diameter. Moreover, cohesive spheroids can be obtained in less than 24 hours. We show the proof of concept of the method using the CT26 murine colon carcinoma cell line and how different cell proliferation and invasion potentials can be attained by varying the spheroid size. Additionally, we show how the spheroid maturation impacts cell invasion and doxorubicin penetrability, highlighting the importance of this parameter in drug screening and therapeutic applications. Finally, we demonstrate the capability of the method to allow the measurement of the spheroid surface tension, a relevant output parameter in the context of cancer cell invasion and metastasis. The method can accommodate other cell lines able to be magnetically labeled, as we demonstrate using the U-87 MG human glioblastoma cell line, and shows promise in the therapeutic screening at early time points of tissue formation, as well as in studies of drug and nanoparticle tumor penetration.The photo-spin-voltaic effect is revealed by the presence of a spin voltage generated by photons when a non-magnetic metal (e.g., Pt) is in close proximity to a ferrimagnetic insulator (e.g., Y3Fe5O12 (YIG)). This is attributed to the excited electrons and holes diffusing from the proximized layer near the interface to the metallic surface. By using a dual-ion-beam sputtering deposition technique, a metallic PtMn layer was deposited on YIG /Gd3Ga5O12 (GGG) (111) substrates. We report on the photo-induced-spin voltaic effect in a PtMn/YIG/GGG heterostructure. Biricodar nmr The sign of the photo-generated voltage was found to switch with magnetic field polarity and its intensity to decrease with increasing PtMn thickness. This indicates that spin-polarized electrons are confined near the interface in the metal. Photo-excitation of these carriers, together with spin-orbit coupling with Pt atoms, is at the origin of the measured transverse voltage. The design may find applications in antiferromagnetic spintronics.The invertebrates ability to adapt to the environment during motion represents an intriguing feature to inspire robotic systems. We analyzed the sipunculid species Phascolosoma stephensoni (Sipunculidae, Annelida), and quantitatively studied the motion behavior of this unsegmented worm. The hydrostatic skeleton and the muscle activity make the infaunal P. stephensoni able to extrude part of its body (the introvert) from its burrow to explore the environment by remaining hidden within the rocky substrate where it settled. The introvert protrusion is associated with changes in the body shape while keeping the overall volume constant. In this study, we employed a marker-less optical tracking strategy to quantitatively study introvert protrusion (i.e. kinematics, elongation percentage and forces exerted) in different navigation media. When P. stephensoni specimens were free in sea water (outside from the burrow), the worms reached lengths up to three times their initial ones after protrusion. Moreover, they were able to elongate their introvert inside a viscous medium such as agar-based hydrogel. In this case, the organisms were able to break the hydrogel material, exerting forces up to 3 N and then to navigate easily inside it, producing stresses of some tens of kPa. Our measurements can be used as guidelines and specifications to design and develop novel smart robotic systems.
Growth Differentiation Factor 11 (GDF11) is an anti-aging factor, yet its role in liver diseases is not established. We evaluated the role of GDF11 in healthy conditions and in the transition from non-alcoholic fatty liver disease (NAFLD) to non-alcoholic steatohepatitis (NASH).
GDF11 mRNA levels positively correlated with NAFLD activity score and with CPT1, SREBP, PPARγ and Col1A1 mRNA levels, and associated to portal fibrosis, in morbidly obese patients with NAFLD/NASH. GDF11-treated mice showed mildly exacerbated hepatic collagen deposition, accompanied by weight loss and without changes in liver steatosis or inflammation. GDF11 triggered ALK5-dependent SMAD2/3 nuclear translocation and the pro-fibrogenic activation of HSC.
GDF11 supplementation promotes mild liver fibrosis. Even considering its beneficial metabolic effects, caution should be taken when considering therapeutics that regulate GDF11.
We analyzed liver biopsies from a cohort of 33 morbidly obese adults with NAFLD/NASH. We determined the correlations in mRNA expression levels between GDF11 and genes involved in NAFLD-to-NASH progression and with pathological features. We also exposed wild type or obese mice with NAFLD to recombinant GDF11 by daily intra-peritoneal injection and monitor the hepatic pathological changes. Finally, we analyzed GDF11-activated signaling pathways in hepatic stellate cells (HSC).
We analyzed liver biopsies from a cohort of 33 morbidly obese adults with NAFLD/NASH. We determined the correlations in mRNA expression levels between GDF11 and genes involved in NAFLD-to-NASH progression and with pathological features. We also exposed wild type or obese mice with NAFLD to recombinant GDF11 by daily intra-peritoneal injection and monitor the hepatic pathological changes. Finally, we analyzed GDF11-activated signaling pathways in hepatic stellate cells (HSC).
Pediatric rolandic arteriovenous malformations (AVMs) present a treatment challenge given the lifetime risk of hemorrhage, rehemorrhage, and associated long-term morbidity. Microsurgical resection has been recommended as the optimal treatment for AVMs in general, but there is no dedicated literature on the outcomes of resection of pediatric rolandic AVMs. Here, the study objective was to review the outcomes of microsurgical resection of pediatric rolandic AVMs in the modern era, together with the utilization of surgical adjuncts including navigation, intraoperative angiography, and neurophysiological monitoring.
The authors performed a retrospective review of patients 18 years of age and younger with cerebral AVMs microsurgically treated between January 2000 and May 2016 at The Hospital for Sick Children. Only those patients with an AVM whose nidus was located within the rolandic region were analyzed. A descriptive analysis was performed to identify patient demographics, preoperative AVM characteristics, al cortex and enables effective resection.
Microsurgical resection of rolandic pediatric AVMs yields excellent AVM obliteration with minimal neurological morbidity in selected patients. The incorporation of surgical adjuncts, including neurophysiological monitoring and neuronavigation, allows accurate demarcation of functional cortex and enables effective resection.
Biportal endoscopic spinal surgery has been performed for several years, and its effectiveness is well known; however, no studies on its safety, specifically intracranial pressure, have been conducted to date. The authors sought to evaluate the effect of biportal endoscopic lumbar discectomy on intracranial pressure by monitoring cervical epidural pressure (CEP) changes throughout the procedure.
Twenty patients undergoing single-level biportal endoscopic lumbar discectomy were enrolled in this study. CEPs were monitored throughout the procedure, consisting of phase 1, establishing the surgical portal and working space; phase 2, performing decompression and discectomy; and phase 3, turning off the fluid irrigation system. After discectomy was completed, the authors evaluated changes in CEP as the irrigation pressure increased serially by adding phase 4, increasing irrigation pressure with outflow open; and phase 5, increasing irrigation pressure with outflow closed.
The mean baseline CEP was measured as 16.65 mm Hg. In phase 1, the mean CEP was 17.3 mm Hg, which was not significantly different from the baseline CEP. In phase 2, the mean CEP abruptly increased up to 35.1 mm Hg when the epidural space was first connected with the working space, followed by stabilization of the CEP at 31.65 mm Hg. In phase 4, the CEP increased as the inflow pressure increased, showing a linear correlation, but not in phase 5. No patients experienced neurological complications.
It is important to ensure that irrigation fluid is not stagnant and is maintained continuously. More attention must be paid to keeping pressures low when opening the epidural space.
It is important to ensure that irrigation fluid is not stagnant and is maintained continuously. More attention must be paid to keeping pressures low when opening the epidural space.
Although increased signal intensity (ISI) on MRI is observed in patients with cervical spinal cord injury (SCI) without major bone injury, alterations in ISI have not been evaluated. The association between postoperative ISI and surgical outcomes remains unclear. This study elucidated whether or not the postoperative classification and alterations in MRI-based ISI of the spinal cord reflected the postoperative symptom severity and surgical outcomes in patients with SCI without major bone injury.
One hundred consecutive patients with SCI without major bone injury (79 male and 21 female) with a mean age of 55 years (range 20-87 years) were included. All patients were treated with laminoplasty and underwent MRI pre- and postoperatively (mean 12.5 ± 0.8 months). ISI was classified into three groups on the basis of sagittal T2-weighted MRI grade 0, none; grade 1, light (obscure); and grade 2, intense (bright). The neurological statuses were evaluated according to the Japanese Orthopaedic Association (JOA) scorostoperatively in 48 patients (48%) and were associated with surgical outcomes.
The use of telemedicine (TM) has long been available, but recent restrictions to hospitals due to the coronavirus disease 2019 (COVID-19) pandemic have accelerated the global implementation of TM. However, evidence on the effectiveness of this technology for the care of spine surgery patients is limited. In this systematic review the authors aimed to examine the current utilization of TM for spine surgery.
Using PubMed, Scopus, and the Cochrane Library, the authors performed a systematic review of the literature focused on the themes of telemedicine and spine surgery. Included in the search were randomized controlled trials, cohort studies, and case-controlled studies. Two independent reviewers conducted the study appraisal, data abstraction, and quality assessments of the studies.
Out of 1463 references from the initial search results, 12 studies met the inclusion criteria. The majority of TM interventions focused on improving perioperative patient communication and patient education by using mobile phone apps, online surveys, or online materials for consent. The studies reported the feasibility of the use of TM for perioperative care and positive user experiences from the patients.
The current increase in TM adoption due to the COVID-19 crisis presents an opportunity to further develop and validate this technology. Early evidence in the literature supports the use of TM as an adjunct to traditional in-person clinical encounters for certain perioperative tasks such as supplemental patient education and postoperative surveys.
The current increase in TM adoption due to the COVID-19 crisis presents an opportunity to further develop and validate this technology. Early evidence in the literature supports the use of TM as an adjunct to traditional in-person clinical encounters for certain perioperative tasks such as supplemental patient education and postoperative surveys.
