BACKGROUND Cavernous malformations (CMs) originating from spinal nerve roots are rare but can present with rapidly progressing neurological deficits. Therefore, quick identification and treatment are ...essential. OBSERVATIONS The authors present the case of a 52-year-old male presenting with headaches and gait disturbance, found to have a CM of the C1 nerve root. The patient underwent successful suboccipital craniectomy and C1 laminectomy, with complete resection of the lesion, preservation of the cervical spinal nerve roots, and symptomatic improvement postoperatively. LESSONS This is the first presentation in the literature of a CM originating from the C1 nerve root. The authors show complete resection of the lesion with preservation of the C1 nerve root. Nerve root lesions usually show insidious symptomatic onset. Quick identification and resection are recommended to prevent permanent neurological disability. https://thejns.org/doi/10.3171/CASE2456
Neurosurgical procedures heavily rely on technological innovation to improve patients care. Focused Ultrasound (FUS) represents a novel and ever-growing technology with roots dating back to the 19th ...century. Now surrounded by state-of-the-art equipment, such as MRI guidance, thermometry, neuronavigation guidance, artificial acoustic windows and implantable devices, FUS employs mechanical waves to deliver a wide spectrum of physical effects, in a non-invasive and precise fashion. Even if most of its applications are nowadays mostly experimental or at the very initial steps into clinical practice, FUS has seen its tools being used in a growing number of diseases and applications, ranging from oncology to cerebrovascular, functional disorders and even neuro- and immune-modulation. This general review aims to provide a comprehensive vision of FUS application for neurological conditions.
•Focused Ultrasound is a novel modality for the treatment of intra-cranial targets.•Focused Ultrasound encompasses many high and medium-low intensity techniques.•More clinical investigations are needed to establish FUS in clinical practice.
BACKGROUND Choroid plexus carcinomas (CPCs) are rare malignant brain tumors primarily affecting children younger than 2 years old. These tumors originate from the choroid plexus epithelium and are a ...subtype of choroid plexus tumors, which account for 1%–4% of pediatric brain tumors. Although CPCs often show a notably high recurrence rate after surgery, the standard treatment approach remains gross-total resection (GTR) of the tumor, given the lack of clinical data supporting the effectiveness of adjunct treatment options such as radiotherapy or chemotherapy. OBSERVATIONS A 16-year-old female with a history of a recurrent cranial CPC resistant to surgery and radiotherapy was treated with CyberKnife stereotactic radiosurgery (SRS), following resection. The procedures successfully maintained local disease control for 41 months; however, there was a subsequent recurrence, ultimately leading to the death of the patient. LESSONS CPC treatment remains challenging. SRS can be used as a viable adjunct to surgery, which remains the gold standard, although it can also be considered for nonsurgical candidates or when GTR cannot be achieved. Nevertheless, it is crucial to conduct additional research to explore diverse approaches for radiosurgery, including its role as the primary treatment modality versus its combination with surgery, radiotherapy, or chemotherapy. https://thejns.org/doi/10.3171/CASE23748
Plasmacytoma, a rare plasma cell disorder, often presents as a solitary or multiple tumors within the bone marrow or soft tissues, typically associated with multiple myeloma. Extramedullary ...plasmacytomas (EMPs), particularly those located in the external auditory canal (EAC), are exceedingly rare and pose significant treatment challenges given their location, anatomical complexity, and high risk of recurrence.
The authors report the case of a 72-year-old male with a history of multiple myeloma, presenting with recurrent left EAC plasmacytoma. After initial conventional radiotherapy for the lesion, a recurrence was documented in 7 years. The patient subsequently underwent stereotactic radiosurgery, which proved successful, leading to complete resolution of the lesion without any long-term adverse effects or radiation-related complications over a 45-month period.
This case is a unique instance of utilizing stereotactic radiosurgery for recurrent EMP in the EAC, highlighting its potential as an effective approach in managing complex plasmacytomas.
The rapid growth of consumer unmanned aerial vehicles (UAVs) is creating promising new business opportunities for cellular operators. On the one hand, UAVs can be connected to cellular networks as ...new types of user equipment, therefore generating significant revenues for the operators that can guarantee their stringent service requirements. On the other hand, UAVs offer the unprecedented opportunity to realize UAV-mounted flying base stations (BSs) that can dynamically reposition themselves to boost coverage, spectral efficiency, and user quality of experience. Indeed, the standardization bodies are currently exploring possibilities for serving commercial UAVs with cellular networks. Industries are beginning to trial early prototypes of flying BSs or user equipments, while academia is in full swing researching mathematical and algorithmic solutions to address interesting new problems arising from flying nodes in cellular networks. In this paper, we provide a comprehensive survey of all of these developments promoting smooth integration of UAVs into cellular networks. Specifically, we survey: 1) the types of consumer UAVs currently available off-the-shelf; 2) the interference issues and potential solutions addressed by standardization bodies for serving aerial users with the existing terrestrial BSs; 3) the challenges and opportunities for assisting cellular communications with UAV-based flying relays and BSs; 4) the ongoing prototyping and test bed activities; 5) the new regulations being developed to manage the commercial use of UAVs; and 6) the cyber-physical security of UAV-assisted cellular communications.
We present single-cell clustering using bifurcation analysis (SCUBA), a novel computational method for extracting lineage relationships from single-cell gene expression data and modeling the dynamic ...changes associated with cell differentiation. SCUBA draws techniques from nonlinear dynamics and stochastic differential equation theories, providing a systematic framework for modeling complex processes involving multilineage specifications. By applying SCUBA to analyze two complementary, publicly available datasets we successfully reconstructed the cellular hierarchy during early development of mouse embryos, modeled the dynamic changes in gene expression patterns, and predicted the effects of perturbing key transcriptional regulators on inducing lineage biases. The results were robust with respect to experimental platform differences between RT-PCR and RNA sequencing. We selectively tested our predictions in Nanog mutants and found good agreement between SCUBA predictions and the experimental data. We further extended the utility of SCUBA by developing a method to reconstruct missing temporal-order information from a typical single-cell dataset. Analysis of a hematopoietic dataset suggests that our method is effective for reconstructing gene expression dynamics during human B-cell development. In summary, SCUBA provides a useful single-cell data analysis tool that is well-suited for the investigation of developmental processes.
Significance Characterization of cellular heterogeneity and hierarchy are important tasks in developmental biology and may help overcome drug resistance in treatment of cancer and other diseases. Single-cell technologies provide a powerful tool for detecting rare cell types and cell-fate transition events, whereas traditional gene expression profiling methods can be used only to measure the average behavior of a cell population. However, the lack of suitable computational methods for single-cell data analysis has become a bottleneck. Here we present a method with the focuses on automatically detecting multilineage transitions and on modeling the associated changes in gene expression patterns. We show that our method is generally applicable and that its applications provide biological insights into developmental processes.
Cell death assays for drug discovery Yuan, Junying; Kroemer, Guido; Kepp, Oliver ...
Nature reviews. Drug discovery,
201103, 2011-Mar, 2011-3-1, 20110301, Volume:
10, Issue:
3
Journal Article
Peer reviewed
Cell death has an important role in many human diseases, and strategies aimed at modulating the associated pathways have been successfully applied to treat various disorders. Indeed, several ...clinically promising cytotoxic and cytoprotective agents with potential applications in cancer, ischaemic and neurodegenerative diseases have recently been identified by high-throughput screening (HTS), based on appropriate cell death assays. Given that different cell death modalities may be dysregulated in different diseases, it is becoming increasingly clear that such assays need to not only quantify the extent of cell death, but they must also be able to distinguish between the various pathways. Here, we systematically describe approaches to accurately quantify distinct cell death pathways, discuss their advantages and pitfalls, and focus on those techniques that are amenable to HTS.
Calcium phosphate (CaP) ceramics have been widely used for bone regeneration because of their ability to induce osteogenesis. Surface properties, including chemical composition and surface structure, ...are known to play a crucial role in osteoconduction and osteoinduction. This review systematically analyzes the effects of surface properties, in particular the surface structure, of CaP scaffolds on cell behavior and new bone formation. We also summarize the possible signaling pathways involved in the osteogenic differentiation of bone-related cells when cultured on surfaces with various structures in vitro. The significant immune response initiated by surface structure involved in osteogenic differentiation of cells is also discussed in this review. Taken together, the new biological principle for advanced biomaterials is not only to directly stimulate osteogenic differentiation of bone-related cells but also to modulate the immune response in vivo. Although the reaction mechanism responsible for bone formation induced by CaP surface structure is not clear yet, the insights on surface structure-mediated osteogenic differentiation and osteoimmunomodulation could aid the optimization of CaP-based biomaterials for bone regeneration.
CaP ceramics have similar inorganic composition with natural bone, which have been widely used for bone tissue scaffolds. CaP themselves are not osteoinductive; however, osteoinductive properties could be introduced to CaP materials by surface engineering. This paper systematically summarizes the effects of surface properties, especially surface structure, of CaP scaffolds on bone formation. Additionally, increasing evidence has proved that the bone healing process is not only affected by the osteogenic differentiation of bone-related cells, but also relevant to the the cooperation of immune system. Thus, we further review the possible signaling pathways involved in the osteogenic differentiation and immune response of cells cultured on scaffold surface. These insights into surface structure-mediated osteogenic differentiation and osteoimmunomodulated-based strategy could aid the optimization of CaP-based biomaterials.
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The presence of the wind-waves enhances the flow turbulent complexity and modifies the dynamic behaviour of the tidal-stream turbine and causes extra challenges for its performance and survivability. ...A sign of these effects is the modification of the turbine wake under the action of wind-waves, thus assessing the resulting wake characteristics is fundamental for technological development of such devices in single or array configurations. Laboratory experiments, involving regular waves propagating with the current, were conducted to describe the wake structure of a fixed scale model tidal-stream turbine. In order to highlight wave effects, the laboratory measurements are analysed in term of: (i) time-mean velocity profiles, (ii) swirl numbers, (iii) turbulence intensities and (iv) turbulent anisotropy maps. In each case, distinctive features are discussed in the downstream rotor near and far fields. The velocity profile is slightly affected by the waves in both near and far fields. The swirl number in the near field is drastically influenced by waves presence where a significant correlation with the wave-steepness is highlighted. Wave presence also affects the turbulence intensities both in the near and far field. This phenomenon is more evident at the top-tip and rotor–centreline water depth instead of in the bottom-tip level. The analysis of turbulent anisotropy maps shows that waves act on the wake flow leading to axisymmetric turbulent conditions mainly dominated by the axial turbulence component. These results constitute an initial step toward the understanding of unsteady wake interactions, in arrays of tidal stream turbines.
•The regular waves influence slightly the mean wake profile.•Steeper waves drastically hinder the decay of swirling numbers.•The presence of the waves significantly affects the turbulence in the wake field.•The Lumley triangles are performed to analyse the state of anisotropy.
•Considering various slenderness ratios, the axial compression performance of buckling behavior of PBSL column was presented.•Elastic eigenvalue analysis is found effective to predict critical ...buckling load of long columns.•Inelastic behavior has significant effect on critical load when the buckling stress exceeds proportional limit of the material.•The presented experimental results and numerical analysis validated the feasibility of the elastic/inelastic buckling analysis approaches on determination of ultimate capacity of axial loaded PBSL columns.
This paper presents an investigation on the mechanical performance of parallel bamboo strand lumber (PBSL) columns under axial compression. Experimental test and numerical analysis were performed for 40 PBSL columns with various slenderness ratios. Failure modes, ultimate capacity and load-strain response are reported and evaluated. Compressive failure is the typical failure mode of columns with small slenderness ratios, however, buckling failure is commonly observed for longer columns. Elastic eigenvalue analysis is found effective to predict critical buckling load of long columns, as buckling occurs within elastic range. However inelastic behavior has significant effect on critical load when the buckling stress exceeds proportional limit of the material. As a result, inelastic approaches provide more accurate prediction of critical load for columns with a slenderness ratio lower than the elastic threshold (λy). The presented experimental results and numerical analysis validated the feasibility of the elastic/inelastic buckling analysis approaches on determination of ultimate capacity of axial loaded PBSL columns.
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