Background: Patients with adolescent idiopathic scoliosis (AIS) are typically treated surgically with posterior spinal fusion (PSF) when the curve continues to progress beyond 45 to 50 degrees. In adult patients, studies have shown that preoperative psychiatric diagnoses are associated with poorer clinical outcomes after lumbar spine surgery. This study aims to address whether a preoperative mental health disorder affects outcomes in pediatric patients with AIS treated with PSF.
View Article and Find Full Text PDFStudy Design: Technical report.
Objectives: Dural tear is one of the most common complications of endoscopic spine surgery. Although endoscopic dural repair of the durotomy area may be difficult, we successfully repaired the dural tear area using nonpenetrating clips during biportal endoscopic surgery.
Background: Bilateral or huge disc herniations cause bilateral radiculopathy and severe lower back pain. In such cases, a bilateral discectomy may be required to resolve the radicular pain in both legs. We attempted a surgical technique involving bilateral lumbar discectomy via a unilateral approach using a percutaneous biportal endoscopic technique.
View Article and Find Full Text PDFACS Appl Mater Interfaces
March 2019
The durability of alkaline anion exchange membrane (AEM) electrolyzers is a critical requirement for implementing this technology in cost-effective hydrogen production. Here, we report that the electrochemical oxidation of the adsorbed phenyl group (found in the ionomer) on oxygen evolution catalysts produces phenol, which may cause performance deterioration in AEM electrolyzers. In-line H NMR kinetic analyses of phenyl oxidation in a model organic cation electrolyte shows that catalyst type significantly impacts the phenyl oxidation rate at an oxygen evolution potential.
View Article and Find Full Text PDFDevelopment of alternative energy sources is crucial to tackle challenges encountered by the growing global energy demand. Hydrogen fuel, a promising way to store energy produced from renewable power sources, can be converted into electrical energy at high efficiency via direct electrochemical conversion in fuel cells, releasing water as the sole byproduct. One important drawback to current fuel-cell technology is the high content of platinum-group-metal (PGM) electrocatalysts required to perform the sluggish oxygen reduction reaction (ORR).
View Article and Find Full Text PDFThe synthesis, characterization, and electrocatalytic properties of mesoporous carbon materials doped with nitrogen atoms and iron are reported and compared for the catalyzed reduction of oxygen gas at fuel cell cathodes. Mixtures of common and inexpensive organic precursors, melamine, and formaldehyde were pyrolyzed in the presence of transition-metal salts (e.g.
View Article and Find Full Text PDFSlow hydrogen oxidation reaction (HOR) kinetics on Pt under alkaline conditions is a significant technical barrier for the development of high-performance hydroxide exchange membrane fuel cells. Here we report that benzene adsorption on Pt is a major factor responsible for the sluggish HOR. Furthermore, we demonstrate that bimetallic catalysts, such as PtMo/C, PtNi/C, and PtRu/C, can reduce the adsorption of benzene and thereby improve HOR activity.
View Article and Find Full Text PDFPlatinum group metal-free (PGM-free) metal-nitrogen-carbon catalysts have emerged as a promising alternative to their costly platinum (Pt)-based counterparts in polymer electrolyte fuel cells (PEFCs) but still face some major challenges, including (i) the identification of the most relevant catalytic site for the oxygen reduction reaction (ORR) and (ii) demonstration of competitive PEFC performance under automotive-application conditions in the hydrogen (H)-air fuel cell. Herein, we demonstrate H-air performance gains achieved with an iron-nitrogen-carbon catalyst synthesized with two nitrogen precursors that developed hierarchical porosity. Current densities recorded in the kinetic region of cathode operation, at fuel cell voltages greater than ~0.
View Article and Find Full Text PDFPurpose: Levothyroxine supplementation is insufficient for the management of one tenth of patients with hypothyroidism. Iodothyronine deiodinases have been suggested to play a role in residual hypothyroid symptoms of these patients by controlling local thyroid hormone homeostasis. Previous research has suggested a relationship between commonly inherited variations in type 2 iodothyronine deiodinase and impaired well-being.
View Article and Find Full Text PDFThis article reports on the characterization of polymer electrolyte fuel cell (PEFC) cathodes featuring a platinum group metal-free (PGM-free) catalyst using nanoscale resolution X-ray computed tomography (nano-CT) and morphological analysis. PGM-free PEFC cathodes have gained significant interest in the past decade since they have the potential to dramatically reduce PEFC costs by eliminating the large platinum (Pt) raw material cost. However, several challenges remain before they are commercially viable.
View Article and Find Full Text PDFRotating disk electrode voltammograms and infrared reflection absorption spectra indicate that the hydrogen oxidation reaction of platinum in 0.1 M tetramethylammonium hydroxide solution is adversely impacted by time-dependent and potential-driven cation-hydroxide-water coadsorption. Impedance analysis suggests that the hydrogen oxidation reaction inhibition is mainly caused by the hydrogen diffusion barrier of the coadsorbed trilayer rather than intuitive catalyst site blocking by the adsorbed cation species.
View Article and Find Full Text PDFObjectives/hypothesis: The aim of this study was to evaluate the clinicopathologic characteristics and pattern of lymph node (LN) metastasis in papillary thyroid cancer (PTC) located in the isthmus.
Study Design: Retrospective cohort study.
Methods: One hundred ninety consecutive patients with PTC who underwent total thyroidectomy and bilateral central neck dissection were analyzed.
Nitrogen-doped carbon nanotubes (N-CNTs) have shown promising performance in a variety of applications: catalysts, catalyst supports, lithium-ion batteries and supercapacitors. While chemical vapor deposition continues to be the most common method for N-CNT fabrication, its complexity and high cost have prevented the practical implementation of N-CNTs on a larger scale. Here, we describe a new and simple method for N-CNT synthesis.
View Article and Find Full Text PDFMaxillofac Plast Reconstr Surg
December 2015
Arthroscopy is useful to detect early changes in the temporomandibular joint (TMJ). Despite great advances in arthroscopy, many arthroscopic surgeries have now been replaced by arthrocentesis. We propose a simple diagnostic and therapeutic method having operative rigid ultra-thin arthroscopy with 16 gauge needle size combined with arthrocentesis.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
June 2015
Dimethyl ether (DME) has been considered as a promising alternative fuel for direct-feed fuel cells but lack of an efficient DME oxidation electrocatalyst has remained the challenge for the commercialization of the direct DME fuel cell. The commonly studied binary PtRu catalyst shows much lower activity in DME than methanol oxidation. In this work, guided by density functional theory (DFT) calculation, a ternary carbon-supported PtRuPd catalyst was designed and synthesized for DME electrooxidation.
View Article and Find Full Text PDFGene therapy is the treatment of human disorders by the introduction of genetic material to specific target cells of a patient. Chitosan and its derivatives show excellent biological properties including biocompatibility, biodegradability and nonallergenicity. Primary amines of chitosan are responsible for its cationic nature and hence binding and protection of DNA for intracellular delivery.
View Article and Find Full Text PDFHere, we introduce a polydixylitol based highly osmotic polymer that not only transmigrates the BBB by intra-arterial infusion of osmotic polyol but also triggers cellular uptake via modulation of caveolae mediated endocytosis.
View Article and Find Full Text PDFThe occurrence of glycemic disturbances has been described for patients undergoing intermittent hepatic inflow occlusion (IHIO) for tumor removal. However, the glycemic responses to IHIO in living liver donors are unknown. This study investigated the glycemic response to IHIO in these patients and examined the association between this procedure and the occurrence of hyperglycemia (blood glucose > 180 mg/dL).
View Article and Find Full Text PDFActa Otolaryngol
February 2014
Conclusion: Based on the Tinnitus Handicap Inventory (THI) and visual analog scale (VAS) scores, transcutaneous electrical stimulation (TENS) can provide relief from tinnitus. Response to electrical stimulation was best seen in patients with low-frequency tinnitus and with mild hearing loss.
Objective: TENS is known to alleviate symptoms of tinnitus.
Nanostructured carbon-based materials, such as nitrogen-doped carbon nanotube arrays, Co3O4/nitrogen-doped graphene hybrids and carbon nanotube-graphene complexes have shown respectable oxygen reduction reaction activity in alkaline media. Although certainly promising, the performance of these materials does not yet warrant implementation in the energy conversion/storage devices utilizing basic electrolytes, for example, alkaline fuel cells, metal-air batteries and certain electrolysers. Here we demonstrate a new type of nitrogen-doped carbon nanotube/nanoparticle composite oxygen reduction reaction electrocatalyst obtained from iron acetate as an iron precursor and from cyanamide as a nitrogen and carbon nanotube precursor in a simple, scalable and single-step method.
View Article and Find Full Text PDFBackground: Ferulic acid (FA) is a naturally occurring nutritional compound. Although it has been shown to have antihypertensive effects, its effects on vascular function have not been intensively established. The aim of this study was to assess the vasoreactivity of FA in chronic two-kidney, one-clip (2K1C) renal hypertensive rats.
View Article and Find Full Text PDFPhotodynamic therapy (PDT) uses the combination of non-toxic dyes and harmless visible light to produce reactive oxygen species that can kill cancer cells and infectious microorganisms. Due to the tendency of most photosensitizers (PS) to be poorly soluble and to form nonphotoactive aggregates, drug-delivery vehicles have become of high importance. The nanotechnology revolution has provided many examples of nanoscale drug-delivery platforms that have been applied to PDT.
View Article and Find Full Text PDFSoon after the discovery of lasers in the 1960s it was realized that laser therapy had the potential to improve wound healing and reduce pain, inflammation and swelling. In recent years the field sometimes known as photobiomodulation has broadened to include light-emitting diodes and other light sources, and the range of wavelengths used now includes many in the red and near infrared. The term "low level laser therapy" or LLLT has become widely recognized and implies the existence of the biphasic dose response or the Arndt-Schulz curve.
View Article and Find Full Text PDFPurpose: The purpose of this study was to evaluate the treatment outcome of temporomandibular joint (TMJ) lysis and lavage using ultrathin TMJ arthroscopy.
Patients And Methods: Closed lock patients who had not shown response to the conservative treatment for more than 3 months were included in this study. The clinical data were collected using standard protocol including questionnaire.