Delicate Structures Research Articles

A novel approach for gingiva thickness measurements around lower anterior teeth by means of dental magnetic resonance imaging

ObjectiveThis diagnostic accuracy study aims to present the first measurements of gingiva thickness around lower anterior teeth using dental magnetic resonance imaging (MRI) and to compare these measurements with two established methods: (1) gingival phenotype assessment via periodontal probing, and (2) the superimposition of cone-beam computed tomography (CBCT) scans with intraoral scans of teeth and gums.Materials and methodsTen patients with substantial orthodontic treatment need and anterior mandibular crowding were consecutively included in this clinical case series. After periodontal probing, each patient underwent a CBCT scan, an intraoral scan of the mandible, and an MRI investigation using a novel mandibula 15-channel dental coil.ResultsThe mean gingiva thickness was 0.72 mm measured on MRI and 0.97 mm measured on CBCT, with a mean difference between the measurement methods of 0.17 ± 0.27 mm (p < 0.001). Measurement agreement between the index tests (MRI and CBCT) and the clinical reference standard (probing) yielded an overall percent agreement of 64.94% and 47.02% for MRI and CBCT, respectively. Teeth with thin phenotypes were associated with lower soft tissue dimensions in both free (MRI: 0.56 mm vs. CBCT: 0.79 mm) and supracrestal gingiva (MRI: 0.75 mm vs. CBCT: 1.03 mm) when compared to those with thick phenotypes. However, only the measurements obtained from MRI scans showed statistically significant differences between the two phenotypes.ConclusionDental MRI successfully visualizes delicate structures like the gingiva in the anterior mandible and achieves a high correlation with superimposed CBCT scans, with clinically acceptable deviations.Clinical relevanceThe present study helps to establish dental MRI as a radiation-free alternative to conventional radiographic methods.

A Rapid Prototyping Approach for Multi-Material, Reversibly Sealed Microfluidics.

Microfluidic organ-on-chip models recapitulate increasingly complex physiological phenomena to study tissue development and disease mechanisms, where there is a growing interest in retrieving delicate biological structures from these devices for downstream analysis. Standard bonding techniques, however, often utilize irreversible sealing, making sample retrieval unfeasible or necessitating destructive methods for disassembly. To address this, several commercial devices employ reversible sealing techniques, though integrating these techniques into early-stage prototyping workflows is often ignored because of the variation and complexity of microfluidic designs. Here, we demonstrate the concerted use of rapid prototyping techniques, including 3D printing and laser cutting, to produce multi-material microfluidic devices that can be reversibly sealed. This is enhanced via the incorporation of acrylic components directly into polydimethylsiloxane channel layers to enhance stability, sealing, and handling. These acrylic components act as a rigid surface separating the multiple mechanical seals created between the bottom substrate, the microfluidic features in the device, and the fluidic interconnect to external tubing, allowing for greater design flexibility. We demonstrate that these devices can be produced reproducibly outside of a cleanroom environment and that they can withstand ~1 bar pressures that are appropriate for a wide range of biological applications. By presenting an accessible and low-cost method, we hope to enable microfluidic prototyping for a broad range of biomedical research applications.

Carbon Monoxide: A Second Biomarker to Couple with Viscosity for the Construction of "Dual-Locked" Near-Infrared Fluorescent Probes for Accurately Diagnosing Non-Alcoholic Fatty Liver Disease.

Nonalcoholic fatty liver disease (NAFLD) can progress to cirrhosis and liver cancer if left untreated. Therefore, it is of great importance to develop useful tools for the noninvasive and accurate diagnosis of NAFLD. Increased microenvironmental viscosity was considered as a biomarker of NAFLD, but the occurrence of increased viscosity in other liver diseases highly reduces the diagnosis accuracy of NAFLD by a single detection of viscosity. Hence, it is very necessary to seek a second biomarker of NAFLD. It has been innovatively proposed that the overexpressed heme oxygenase-1 enzyme in NAFLD would produce abnormally high concentrations of CO in hepatocytes and that CO could serve as a potential biomarker. In this work, we screened nine lactam Changsha dyes (HCO-1-HCO-9) with delicate structures to obtain near-infrared (NIR), metal-free, and "dual-locked" fluorescent probes for the simultaneous detection of CO and viscosity. Changsha dyes with a 2-pyridinyl hydrazone substituent could sense CO, and the 5-position substituents on the 2-pyridinyl moiety had a great electron effect on the reaction rate. The double bond in these dyes served as the sensing group for viscosity. Probe HCO-9 was utilized for precise diagnosis of NAFLD by simultaneous detection of CO and viscosity. Upon reacting with CO in a high-viscosity microenvironment, strong fluorescence at 745 nm of probe HCO-9 was turned on with NIR excitation at 700 nm. Probe HCO-9 was proven to be an effective tool for imaging CO and viscosity. Due to the advantages of NIR absorption and low toxicity, probe HCO-9 was successfully applied to image NAFLD in a mouse model.

Facile synthesis of double yolk-shelled MnO/C microspheres as superior anode materials for lithium-ion batteries

Tenable structure design is vital in the pursuit of advanced anode materials for enhanced lithium storage, but construction of the desired architectures often faces challenges. Herein, we demonstrate the facile fabrication of double yolk-shelled MnO/C microspheres by annealing the solvothermally synthesized Mn-gluconate microspheres under Ar atmosphere, and the double or single yolk-shell structure can be easily regulated by changing the glucose amount. Benefits brought by the unique structure include enlarged surface area, hierarchical pores, abundant reaction sites and increased ion diffusion rate. Besides, combination of MnO with glucose-derived carbon could not only restrict the volume variation of MnO but also increase the electrical conductivity, bringing improved rate capability and enhanced cycling stability. Thus, a high-rate and stable capacity of 611 mAh g−1 after 500 cycles at 1 A g−1 is observed in the lithium-ion batteries adopting the presented double yolk-shelled MnO/C microspheres as the anode materials, thanks to the synergistic structure and composition advantages. Importantly, this study provides a controllable method to construct delicate multi-shelled structures with simultaneous carbon hybridization, which could be promising in fabrication of advanced electrodes for energy-related applications.

Force-adjustable parallel-occlusion grasper.

During laparoscopic surgery, the operating surgeon grasps sections of the gastrointestinal tract (GIT), including delicate structures, with long (270mm) 5mm diameter graspers. These grasping instruments increase the risk of iatrogenic damage due to crushing of the grasped tissue. This risk is increased significantly by diseases such as bacterial peritonitis and inflammatory bowel disease and reduced but not abolished by using parallel-closing laparoscopic instruments. This study describes the design and laboratory testing of fully developed and tested smart graspers capable of reducing the grasping force used for inflamed tissues and hollow viscera. In an ISO 13485-certified mechanical laboratory and CAD machine workshop, the authors have designed, developed, and evaluated a smart gasper capable of exerting a preselected uniform grasping force on the gastrointestinal tract and other structures/ tissues, through a mechanism incorporated in the handle of the instrument. This enables the control and graded reduction of the grasping force by the incorporation of a compression spring. The authors named the new instrument the force-adjustable parallel-occlusion grasper (FA-POG) because, in addition to applying a uniform force on the grasped bowel/tissue, it also enables the surgeon to select the force before grasping, depending on its physical condition, and pathological state. FA-POG differs from traditional pinch-occlusion grasper in two respects: it exerts a uniform force on the grasped tissue/bowel and enables the operating surgeon to select and apply a predetermined uniform grasping force, ranging from 1 to 5 N, depending on the pathological condition of the bowel/structure. The ISO 13485-certified and fully developed prototype has been subjected to various grasping in-vitro tests using freshly harvested porcine small-bowel segments obtained from a local abattoir, using Instron tensiometry. The authors designed and α/β tested a parallel-occlusion gasper that enables the operating surgeon to select the force before grasping. This grasper design consists of end-effectors jaws with a 4-bar linkage mechanism for wide, uniform parallel-occlusion force, surpassing traditional scissor-type laparoscopic graspers. It incorporates a force-level controller knob, based on a spring-loaded mechanism, enabling surgeon-preselected grip force to prevent excessive grasping. The authors validated the design experimentally using porcine small-bowel segments, optimizing teeth for maximum grip friction to minimize slippage.

EYESPIRATOR- A novel do-it-yourself suction device.

Surgery, by nature, involves blood loss. Thus, suction plays an important role in ensuring a clean operating view and ease of access. In ophthalmology, there is a void for an efficient and flexible suction apparatus that is yet to be filled. Our innovation, the Eyespirator, is made using recycled or inexpensive parts, is easy to assemble, and can serve as a cost-effective alternative to the current apparatus under use. It helps to overcome the difficulties caused by large instruments and non-pliable suction tips, unregulated generation of vacuum, and high pressures generated causing trauma to the delicate structures, and can prove to be of immense use in fields such as ophthalmology where the small surgical field is a big challenge. It creates a vacuum by using a simple water pump and is regulated by a foot pedal. This can be deployed even in rural settings, and small modifications can allow its usage in a wide variety of surgical fields.

Advancing Antiamyloidogenic Activity by Fine-Tuning Macromolecular Topology.

Amyloid β peptide can aggregate into thin β-sheet fibrils or plaques deposited on the extracellular matrix, which is the hallmark of Alzheimer's disease. Multifunctional macromolecular structures play an important role in inhibiting the aggregate formation of amyloidogenic materials and thus are promising candidates with antiamyloidogenic characteristics for the development of next-generation therapeutics. In this study, we evaluate how small differences in the dendritic topology of these structures influence their antiamyloidogenic activity by the comparison of "perfectly dendritic" and "pseudodendritic" macromolecules, both decorated with mannose units. Their compactness, the position of surface units, and the size of glyco-architectures influence their antiamyloidogenic activity against Aβ 40, a major component of amyloid plaques. For the advanced analysis of the aggregation of the Aβ peptide, we introduce asymmetric flow field flow fractionation as a suitable method for the quantification of large and delicate structures. This alternative method focuses on the quantification of complex aggregates of Aβ 40 and glycodendrimer/glyco-pseudodendrimer over different time intervals of incubation, showing a good correlation to ThT assay and CD spectroscopy results. Kinetic studies of the second-generation glyco-pseudodendrimer revealed maximum inhibition of Aβ 40 aggregates, verified with atomic force microscopy. The second-generation glyco-pseudodendrimer shows the best antiamyloidogenic properties confirming that macromolecular conformation in combination with optimal functional group distribution is the key to its performance. These molecular properties were validated and confirmed by molecular dynamics simulation.

Bio‐inspired metal ion coordination cross‐linking synergistic strategy to enhance the interfacial properties of carbon fiber composites

AbstractThe application of carbon fiber (CF) in carbon fiber composites has faced limitations due to its surface chemical inertness. To overcome this challenge, this study draws inspiration from metal ion‐enhancing exquisite hierarchical and multiphase structures observed in biological materials. The research proposes a novel approach to enhance the interfacial bonding of CF/Epoxy (E‐51) composites by utilizing tannic acid (TA), carboxylated cellulose nanocrystals (CNCs), Fe3+ ions, and polyvinyl alcohol (PVA). This approach aims to create hydrogen bonding and metal synergistic networks on the surface of CFs through metal ion (Mn+) coordination cross‐linking synergistic (MCCS) interactions. Implementing MCCS strategy resulted in significant improvements in the mechanical properties of the hybrid reinforcements compared to untreated CF composites. The flexural strength, flexural modulus, interlaminar shear strength, and interfacial shear strength experienced respective increase of 50.9%, 72.8% 59.4%, and 61.9%. Moreover, the damping properties of the composites exhibited significant improvements. These positive outcomes can be attributed to the formation of chelation and dense hydrogen bonding networks between TA, Fe3+, CNC, and PVA. Furthermore, CNC and PVA formed cross‐linked nanolayers that effectively deflected cracks and facilitated high energy consumption at the interface. This proposed approach provides a sustainable, environmentally friendly, and efficient method for surface modification in the preparation of high‐performance fiber composites.Highlights Metal ion (Mn+) coordination cross‐linking synergistic strategy is proposed. Tannins/Fe3+/CNCs/PVA form multiphase nanolayers. Metal ion coordination cross‐linking enhances delicate multiphase structures. The prepared carbon fiber composites exhibit excellent properties. The as‐prepared carbon fiber composite has promising applications.

NMR analysis of the side-group substituents in welan gum in comparison to gellan gum

The physicochemical properties and applications of polysaccharides are highly dependent on their chemical structures, including the monosaccharide composition, degree of substitution, and position of substituent groups in the backbone. The occurrence of side groups or side chains in the chain backbone of polysaccharides is often an essential factor influencing their conformational and physicochemical properties. Welan gum produced by the fermentation of Sphingomonas sp. ATCC 31555 microorganisms has been widely used in food, construction, and oil drilling fields. While understanding the physicochemical properties of welan gum solution has been highly developed, there is still little information about the determination strategy of the glycosyl side groups in welan gum. In this study, the NMR method was established to quantitatively determine the substituent groups in the chain backbone of welan gum. The delicate chemical structures of welan gum obtained at different fermentation conditions were clarified. The composition and content of side substituents were also identified by high-performance liquid chromatography to confirm the accuracy of NMR analysis. The quantitative determination of substituent groups in gellan gum based on NMR analysis was also elaborated for comparison. This work provides insights for profoundly understanding the structure-function relationship of welan gum.

Identification and Characterization of Tunneling Nanotubes for Intercellular Trafficking.

Tunneling nanotubes (TNTs) are thin membranous channels providing a direct cytoplasmic connection between remote cells. They are commonly observed in different cell cultures and increasing evidence supports their role in intercellular communication, and pathogen and amyloid protein transfer. However, the study of TNTs presents several pitfalls (e.g., difficulty in preserving such delicate structures, possible confusion with other protrusions, structural and functional heterogeneity, etc.) and therefore requires thoroughly designed approaches. The methods described in this protocol represent a guideline for the characterization of TNTs (or TNT-like structures) in cell culture. Specifically, optimized protocols to (1) identify TNTs and the cytoskeletal elements present inside them; (2) evaluate TNT frequency in cell culture; (3) unambiguously distinguish them from other cellular connections or protrusions; (4) monitor their formation in living cells; (5) characterize TNTs by a micropatterning approach; and (6) investigate TNT ultrastructure by cryo-EM are provided. Finally, this article describes how to assess TNT-mediated cell-to-cell transfer of cellular components, which is a fundamental criterion for identifying functional TNTs. © 2023 Wiley Periodicals LLC. Basic Protocol 1: Identification of tunneling nanotubes Alternate Protocol 1: Identifying the cytoskeletal elements present in tunneling nanotubes Alternate Protocol 2: Distinguishing tunneling nanotubes from intercellular bridges formed during cell division Basic Protocol 2: Deciphering tunneling nanotube formation and lifetime by live fluorescent microscopy Alternate Protocol 3: Deciphering tunneling nanotube formation using a live-compatible dye Basic Protocol 3: Assessing tunneling nanotubes functionality in intercellular transfer Alternate Protocol 4: Flow cytometry approach to quantify the rate of vesicle or mitochondria transfer Support Protocol: Controls to support TNT-mediated transfer Basic Protocol 4: Studies of tunneling nanotubes by cell micropatterning Basic Protocol 5: Characterization of the ultrastructure of tunneling nanotubes by cryo-EM.

Laparoscopic Photoacoustic Imaging System Based on Side-Illumination Diffusing Fibers.

To develop a flexible miniaturized photoacoustic (PA) imaging probe for detecting anatomical structures during laparoscopic surgery. The proposed probe aimed to facilitate intraoperative detection of blood vessels and nerve bundles embedded in tissue not directly visible to the operating physician to preserve these delicate and vital structures. We modified a commercially available ultrasound laparoscopic probe by incorporating custom-fabricated side-illumination diffusing fibers that illuminate the probe's field of view. The probe geometry, including the position and orientation of the fibers and the emission angle, was determined using computational models of light propagation in the simulation and subsequently validated through experimental studies. In wire phantom studies within an optical scattering medium, the probe achieved an imaging resolution of 0.43 ±0.09 mm and a signal-to-noise ratio of 31.2±1.84 dB. We also conducted an ex vivo study using a rat model, demonstrating the successful detection of blood vessels and nerves. Our results indicate the viability of a side-illumination diffusing fiber PA imaging system for guidance during laparoscopic surgery. The potential clinical translation of this technology could enhance the preservation of critical vascular structures and nerves, thereby minimizing post-operative complications.

Scalable, Color-Matched, Flexible Plasmonic Film for Visible-Infrared Compatible Camouflage.

The multispectral compatible infrared camouflage technology is implemented these days to counter the developing infrared detectors and detectors of other bands. However, the conflict between delicate optical structures and scalable procedures has significantly impeded the development and application of multispectral-compatible camouflage technology. Therefore, a semi-open Fabry-Perot structure is introduced, and the color and infrared emissivity by structural parameters for color-matched visible-infrared compatible camouflage are modulated. The prepared compatible camouflage film exhibits visible camouflage by the minimum color difference of 1.6 L*a*b* (under desert background) and infrared camouflage by low emission (ε3-5µm ≈ 0.17 and ε8-14µm ≈ 0.143). Due to its flexibility and scalability, the compatible camouflage film can be applied in practical applications and exhibits desirable visible and infrared camouflage performance in different battlefield backgrounds.

Mandibular swing approach for high parapharyngeal space schwannoma

Parapharyngeal space tumours are rare, comprising 0.5% of all head and neck neoplasms. Different surgical approaches to this space have been described based on various criteria. Here, we are presenting a case report of a 65-year-old woman with left vagal schwannoma splaying the left internal carotid artery and internal jugular vein superiorly and splaying the left internal carotid artery and external carotid artery inferiorly, with its upper edge about 0.7 cm caudal to skull base. Surgery by a combined trans-cervical and mandibular swing approach was adopted for this case. The tumour which was extending so close to the skull base was removed in toto with an intact capsule and the neurovascular structures like the carotids, internal jugular vein and the vagus were preserved through a trans-mandibular approach. Postoperatively patient had no neurovascular compromise. Histopathological examination revealed vagal schwannoma. Trans-mandibular approach may appear complex, but it offers excellent surgical field to keep the delicate surrounding structures intact, to reduce the risk of haemorrhagic and avoid neurological complications.

A New, Effective, Safe, and Accurate Method of Cervical Selective Nerve Root Block

Objective: Cervical selective nerve root block (SNRB) is an effective procedure that has long been performed for patients with radiating pain or paresthesia. However, there are several delicate structures around the cervical nerve root, damage to which could lead to irreversible neurovascular injury. Therefore, cervical SNRB requires a high skill level and extensive experience to execute it safely. To overcome these disadvantages, we used biplane computed tomography (CT)-guided fluoroscopy and a needle guidance program to achieve symptom improvement in a safer and shorter procedure. This study aimed to investigate the new method and report on its excellent clinical effects.Methods: A total of 57 patients who experienced radiating pain due to cervical spinal stenosis resulting from a herniated disc were enrolled. From September 2020 to September 2021 subjects underwent a biplane CT-guided fluoroscopic nerve block at an outpatient clinic. All procedures were performed by biplane CT-guided fluoroscopy. We analyzed treatment effects with a numerical rating scale (NRS) at 2 and 4 weeks after the procedure. Logistic regression was performed to reveal the significance of changes in NRS after the injection.Results: Pain improved in 56 of 57 patients (98%) after 2 and 4 weeks of follow-up compared to pre-injection pain. At the 2-week follow-up, the mean reduction based on NRS scores was 3.226 (2.782-3.674, 0; 95% confidence interval [CI], p &lt; 0.001) indicating a 48% decrease in pain scores compared with the initial NRS. The mean reduction in NRS 4 weeks after the procedure was 3.544 (3.090-3.998, 0; 95% CI, p &lt; 0.001) indicating a 52% reduction compared with the initial NRS. The average duration of the procedure was 4 minutes. Conclusion: We demonstrate a clinically effective, safe, and accurate method using a biplane CT-guided fluoroscopy and needle guide program. This new method can be an easy and relatively uncomplicated alternative to treatment for patients with cervical radiculopathy and provides safe and accurate targeting, making it easy for inexperienced surgeons.

Improving vasculoprotective effects of MSCs in coronary microvessels - benefits of 3D culture, sub-populations and heparin.

Opening occluded coronary arteries in patients with myocardial infarction (MI) damages the delicate coronary microvessels through a process called myocardial ischaemia-reperfusion injury. Although mesenchymal stromal cells (MSCs) have the potential to limit this injury, clinical success remains limited. This may be due to (i) poor MSC homing to the heart (ii) infused MSCs, even if derived from the same site, being a heterogeneous population with varying therapeutic efficacy and (iii) conventional 2D culture of MSCs decreasing their homing and beneficial properties. This study investigated whether 3D culture of two distinctly different bone marrow (BM)-derived MSC sub-populations could improve their homing and coronary vasculoprotective efficacy. Intravital imaging of the anaesthetised mouse beating heart was used to investigate the trafficking and microvascular protective effects of two clonally-derived BM-derived MSC lines, namely CD317neg MSCs-Y201 and CD317pos MSCs-Y202, cultured using conventional monolayer and 3D hanging drop methods. 3D culture consistently improved the adhesive behaviour of MSCs-Y201 to various substrates in vitro. However, it was their differential ability to reduce neutrophil events within the coronary capillaries and improve ventricular perfusion in vivo that was most remarkable. Moreover, dual therapy combined with heparin further improved the vasculoprotection afforded by 3D cultured MSCs-Y201 by also modifying platelet as well as neutrophil recruitment, which subsequently led to the greatest salvage of viable myocardium. Therapeutic benefit could mechanistically be explained by reductions in coronary endothelial oxidative stress and intercellular adhesion molecule-1 (ICAM-1)/vascular cell adhesion molecule-1 (VCAM-1) expression. However, since this was noted by both 2D and 3D cultured MSCs-Y201, therapeutic benefit is likely explained by the fact that 3D cultured MSCs-Y201 were the most potent sub-population at reducing serum levels of several pro-inflammatory cytokines. This novel study highlights the importance of not only 3D culture, but also of a specific CD317neg MSC sub-population, as being critical to realising their full coronary vasculoprotective potential in the injured heart. Since the smallest coronary blood vessels are increasingly recognised as a primary target of reperfusion injury, therapeutic interventions must be able to protect these delicate structures from inflammatory cells and maintain perfusion in the heart. We propose that relatively feasible technical modifications in a specific BM-derived MSC sub-population could achieve this.

A data integration approach unveils a transcriptional signature of type 2 diabetes progression in rat and human islets.

Pancreatic islet failure is a key characteristic of type 2 diabetes besides insulin resistance. To get molecular insights into the pathology of islets in type 2 diabetes, we developed a computational approach to integrating expression profiles of Goto-Kakizaki and Wistar rat islets from a designed experiment with those of the human islets from an observational study. A principal gene-eigenvector in the expression profiles characterized by up-regulated angiogenesis and down-regulated oxidative phosphorylation was identified conserved across the two species. In the case of Goto-Kakizaki versus Wistar islets, such alteration in gene expression can be verified directly by the treatment-control tests over time, and corresponds to the alteration of α/β-cell distribution obtained by quantifying the islet micrographs. Furthermore, the correspondence between the dual sample- and gene-eigenvectors unveils more delicate structures. In the case of rats, the up- and down-trend of insulin mRNA levels before and after week 8 correspond respectively to the top two principal eigenvectors. In the case of human, the top two principal eigenvectors correspond respectively to the late and early stages of diabetes. According to the aggregated expression signature, a large portion of genes involved in the hypoxia-inducible factor signaling pathway, which activates transcription of angiogenesis, were significantly up-regulated. Furthermore, top-ranked anti-angiogenic genes THBS1 and PEDF indicate the existence of a counteractive mechanism that is in line with thickened and fragmented capillaries found in the deteriorated islets. Overall, the integrative analysis unravels the principal transcriptional alterations underlying the islet deterioration of morphology and insulin secretion along type 2 diabetes progression.

A dual-axis mechanical model for analyzing the capillary-force-induced clustering on periodic structures

Structural integrity and robustness are key parameters to evaluate microfabrication techniques. Bending and collapsing of 2D/3D microstructures are commonly noted in solvent-involved procedures, e.g., liquid-based post-treatment in wet-etching, lithography, and Two Photon Polymerizations (TPPs). Such structural failures are caused by excessive solution-imposed capillary forces, where multiple kinds of liquids may intensively participate. Current pieces of the literature focus on the mechanical one-axis models to illustrate their deformation process. To date, there exists an emerging demand for dual-axis models to satisfy rapidly developed micro/nano-engineerings. Here, utilizing polymer micro-pillars distributed in a square array as an illustration example, a dual-axis beam-sway model is proposed considering the influences of structure arrangement as well as the solvent. Specifically, a simplified criterion for judging structural stability is identified. For verifications, the TPP-based experimental data show excellent consistency with model predictions. All in all, the extended model offers reliable guidance for the fabrication of delicate structures and further benefits the optimization of related microfabrication processes.

A Comprehensive Analysis of Noise-Induced Hearing Loss and Its Ayurvedic Insight

Noise-induced hearing loss (NIHL) is a growing global health concern, primarily attributed to our increasingly noisy environments. This comprehensive analysis delves into the multifaceted aspects of NIHL while exploring potential insights from Ayurveda, an ancient Indian system of medicine. NIHL results from prolonged exposure to loud noise levels, causing damage to the delicate structures of the inner ear. It is a gradual and irreversible condition that affects millions of people worldwide, impacting their quality of life and overall health. Traditional approaches to NIHL management primarily focus on hearing aids and protective measures. However, this analysis seeks to integrate Ayurvedic principles and treatments to offer a holistic perspective on NIHL prevention and management. Ayurveda, with its holistic approach to health, considers the interplay of physical, mental, and environmental factors. In Ayurveda, hearing loss can be linked to imbalances in the doshas (Vata, Pitta, and Kapha) and the accumulation of toxins in the body. By addressing these imbalances through dietary modifications, lifestyle changes, and herbal remedies, Ayurveda may offer valuable insights into preventing and managing NIHL. The analysis highlights the importance of noise awareness, emphasizing the need for public health campaigns and workplace regulations to reduce noise exposure. Additionally, it explores Ayurvedic herbs and therapies known for their potential in mitigating the effects of NIHL, such as Ashwagandha (Withania somnifera) and Panchakarma detoxification procedures. Furthermore, the study discusses the role of yoga and meditation in stress management, as chronic stress can exacerbate NIHL. Ayurvedic practices like Pranayama (breathing exercises) and Shirodhara (oil therapy for the head) may promote relaxation and reduce stress, contributing to overall hearing health. In conclusion, this analysis offers a comprehensive overview of NIHL, including its causes, symptoms, and conventional management strategies. By incorporating Ayurvedic insights, we explore a holistic approach to NIHL prevention and management, acknowledging the potential benefits of Ayurveda in promoting hearing health. Further research and collaboration between traditional and modern healthcare systems are essential to harness the full potential of Ayurveda in addressing the global issue of NIHL.

Endoscopic trans-Magendie foramen biopsy of the superior medullary velum: Technical note

BackgroundSurgery of the fourth ventricle is challenging due to the presence of several surrounding delicate structures. Traditional approaches do not offer an easy visualization of these areas, especially those on the roof. Thanks to the most recent developments in neurosurgical endoscopy, it is possible to access the fourth ventricle via physiological pathways, avoiding unnecessary stress or damage to the nervous and vascular structures. MethodsWe present the case of a patient with a lesion at the lingula-superior medullary velum, and an history of surgically resected lung and pancreatic adenocarcinomas. An endoscopic biopsy of the lesion through the foramen of Magendie was performed. The few reports on this endoscopic approach were also critically reviewed. ResultsThe retrograde endoscopic exploration through a suboccipital, trans-Magendie foramen approach using a flexible endoscope allowed the clear visualization of the superior medullary velum and the possibility to obtain diagnostic biopsies of the lesion with a minimally invasive technique. ConclusionsThe trans-Magendie navigation with a flexible endoscope is a safe and elegant technique to approach lesions located in any point of the fourth ventricle, particularly in its rostral portion.

Impact of inner ear malformation and cochlear nerve deficiency on the development of auditory-language network in children with profound sensorineural hearing loss.

Profound congenital sensorineural hearing loss (SNHL) prevents children from developing spoken language. Cochlear implantation and auditory brainstem implantation can provide partial hearing sensation, but language development outcomes can vary, particularly for patients with inner ear malformations and/or cochlear nerve deficiency (IEM&CND). Currently, the peripheral auditory structure is evaluated through visual inspection of clinical imaging, but this method is insufficient for surgical planning and prognosis. The central auditory pathway is also challenging to examine in vivo due to its delicate subcortical structures. Previous attempts to locate subcortical auditory nuclei using fMRI responses to sounds are not applicable to patients with profound hearing loss as no auditory brainstem responses can be detected in these individuals, making it impossible to capture corresponding blood oxygen signals in fMRI. In this study, we developed a new pipeline for mapping the auditory pathway using structural and diffusional MRI. We used a fixel-based approach to investigate the structural development of the auditory-language network for profound SNHL children with normal peripheral structure and those with IEM&CND under 6 years old. Our findings indicate that the language pathway is more sensitive to peripheral auditory condition than the central auditory pathway, highlighting the importance of early intervention for profound SNHL children to provide timely speech inputs. We also propose a comprehensive pre-surgical evaluation extending from the cochlea to the auditory-language network, showing significant correlations between age, gender, Cn.VIII median contrast value, and the language network with post-implant qualitative outcomes.