ABSTRACT
OBJECTIVES: This study aims to evaluate the potential benefits of combining tongue reduction with mandibular setback surgery in patients undergoing class III orthognathic surgery. Specifically, we investigated whether this combined approach reduced the risk of surgical relapse, condylar resorption, and airway space reduction by mitigating tongue pressure on the mandible. MATERIAL AND METHODS: The study retrospectively enrolled patients who had undergone bilateral sagittal split ramus osteotomy (BSSRO) with at least 5 mm of setback and met the criteria of a body mass index > 20 kg/m2 and tongue volume > 100 mm3. The study included 20 patients with 10 in the tongue reduction group (TR, n = 10) and 10 in the BSSRO only group (SO, n = 10). RESULTS: The volumetric changes of the total airway space were significantly different between the TR and SO groups (p = 0.028). However, no significant differences were observed in the condylar resorption and postoperative relapse between the groups (p = 0.927 and 0.913, respectively). The difference between the resorption of the anterior and posterior segments of the condyle was also statistically insignificant (p = 0.826). Postoperative counterclockwise rotation of the proximal segment only demonstrated a significant correlation with postoperative relapse (p = 0.048). CONCLUSIONS: The reduction in tongue volume demonstrated a preventive effect on the reduction of the airway space after mandibular setback, although it did not yield statistical significance concerning surgical relapse and condylar volume. The counterclockwise rotation of the proximal segment might be responsible for the forward displacement of the distal segment and postoperative relapse. However, the clinical implications of this finding should be interpreted with caution owing to the limited sample size CLINICAL RELEVANCE: Tongue reduction could potentially serve as a preventive measure in preserving the airway space and might be beneficial in mitigating the risk of obstructive sleep apnea in patients with class III deformity.
Subject(s)
Malocclusion, Angle Class III , Orthognathic Surgery , Humans , Mandibular Condyle , Retrospective Studies , Pressure , Tongue , Mandible/surgery , Osteotomy, Sagittal Split Ramus/methods , Recurrence , Cephalometry/methods , Malocclusion, Angle Class III/surgeryABSTRACT
Phosphorus is not only an import nutrient to aquatic habitats, but it also acts as a growth inhibitor in aquatic ecosystems; however, it also aggravates environmental issues, such as eutrophication. There is a growing interest in rapid phosphorus detection to manage and protect water resources. Due to the large molecular structure and high hydration energy of phosphate ions, ion-selective electrodes (ISEs) remain in their infancy for real-time measurements in terms of practical application. In this study, a newly developed ionophore based on a biomimetic nicotinamide functional group was used to detect phosphate selectively, displaying efficient binding through charge interactions and hydrogen bonds. The ISE membrane containing silicone rubber demonstrated an effective detection performance over a long period of time. With a dynamic range between 10-6 and 10-2 M and a limit of detection of 0.85 × 10-6 M (26 µg/L), the newly synthesized ISE membranes demonstrated selectivity for phosphate ions over other ions, including acetate, sulfate, and chloride.
ABSTRACT
A novel and facile post-mortem interval (PMI) biosensor was fabricated using a double-label strategy to detect the glyceraldehyde 3-phosphate dehydrogenase (GAPDH) biomarker. A monoclonal anti-GAPDH antibody was immobilized on a surface label containing cadmium selenide quantum dots (CdSe QDs) on a cysteamine graphene oxide (Cys-GO) self-assembled monolayer. Glucose oxidase (GOx) was used as a signal label to conjugate with GAPDH. GAPDH recognition was achieved through the dissolution of the surface-attached CdSe QDs by hydrogen peroxide generated through GAPDH-conjugated GOx-catalyzed ß-glucose oxidation. To enhance sensitivity, a competitive interaction was introduced between free and conjugated GAPDH to the active site of the anti-GAPDH antibody. The electrochemical response due to CdSe dissolution decreased proportionally with the concentration of free GAPDH. Differential pulsed voltammetry was conducted to determine the analytical characteristics of the immunosensor, including the limit of detection, linear dynamic range, target selectivity, system stability, and applicability toward the analysis of real samples.
Subject(s)
Biosensing Techniques , Quantum Dots , Biomarkers , Electrochemical Techniques , Glucose Oxidase , Immunoassay , Limit of Detection , Quantum Dots/chemistry , SolubilityABSTRACT
Phosphate sensors have been actively studied owing to their importance in water environment monitoring because phosphate is one of the nutrients that result in algal blooms. As with other nutrients, seamless monitoring of phosphate is important for understanding and evaluating eutrophication. However, field-deployable phosphate sensors have not been well developed yet due to the chemical characteristics of phosphate. In this paper, we report on a luminescent coordination polymer particle (CPP) that can respond selectively and sensitively to a phosphate ion against other ions in an aquatic ecosystem. The CPPs with an average size of 88.1 ± 12.2 nm are embedded into membranes for reusable purpose. Due to the specific binding of phosphates to europium ions, the luminescence quenching behavior of CPPs embedded into membranes shows a linear relationship with phosphate concentrations (3-500 µM) and detection limit of 1.52 µM. Consistent luminescence signals were also observed during repeated measurements in the pH range of 3-10. Moreover, the practical application was confirmed by sensing phosphate in actual environmental samples such as tap water and lake water.
ABSTRACT
OBJECTIVES: This study evaluates soft tissue changes of the upper lip and nose after maxillary setback with orthognathic surgery such as Le Fort I or anterior segmental osteotomy. MATERIALS AND METHODS: All 50 patients with bimaxillary protrusion and skeletal Class II malocclusion underwent Le Fort I or anterior segmental osteotomy with backward movement. Soft and hard tissue changes were analyzed using cephalograms collected preoperatively and 6 months postoperatively. RESULTS: Cluster analysis on the ratios shows that 2 lines intersected at 4 mm point. Based on this point, we divided the subjects into 2 groups: Group A (less than 4 mm, 27 subjects) and Group B (more than 4 mm, 23 subjects). Also, each group was divided according to changes of upper incisor angle (≥4°=A1, B1 or <4°=A2, B2). The correlation between A and B groups for A'/ANS and Ls/Is (P<0.001) was significant; A'/A (P=0.002), PRN/A (P=0.043), PRN/ANS (P=0.032), and St/Is (P=0.010). Variation of nasolabial angle between the two groups was not significant. There was no significant correlation of vertical movement and angle variation. CONCLUSION: The ratio of soft tissue to hard tissue movement depends on the amount of posterior movement in the maxilla, showing approximately two times higher rates in most of the midface when posterior movement was greater than 4 mm. The soft tissue changes caused by posterior movement of the maxilla were little affected by angular changes of upper incisors. Interestingly, nasolabial angle showed a different tendency between A and B groups and was more affected by incisal angular changes when horizontal posterior movement was less than 4 mm.
ABSTRACT
Recently graphene has been drawing tremendous attention mainly due to its potential contributions to applications in biology, information technology and energy. Among these applications graphene-based biosensors have been particularly progressed caused in part by development of diverse derivatives of graphene such as graphene oxides (GOs) and graphene quantum dots (GQDs). In this chapter preparation and functionalization of the graphene and GOQs are described together with their optoelectronic properties. Recent progresses in graphene and GQD-based biosensors are also highlighted with emphasis on immunoassay which utilizes unique interaction between antigen and antibody, and oligonucleotide assay which utilizes hybridization process. Since electrical and optical features are the most prominent characteristics of graphene-based nanomaterials, biosensor systems will be focused on electrochemical and fluorescence-based detection scheme.
Subject(s)
Biosensing Techniques , Graphite/chemistry , Nanostructures/chemistry , Immunoassay , Oxides , Quantum Dots/chemistryABSTRACT
Using gold nanoparticles (AuNPs) on "capillary enzyme-linked immunosorbent assay (ELISA)", we produced highly sensitive and rapid assays, which are the major attributes for point-of-care applications. First, in order to understand the size effect of AuNPs, AuNPs of varying diameters (5 nm, 10 nm, 15 nm, 20 nm, 30 nm, and 50 nm) conjugated with Horseradish Peroxidase (HRP)-labeled anti-C reactive protein (antiCRP) (AuNPâ¢antiCRP-HRP) were used for well-plate ELISA. AuNP of 10 nm produced the largest optical density, enabling detection of 0.1 ng/mL of CRP with only 30 s of incubation, in contrast to 10 ng/mL for the ELISA run in the absence of AuNP. Then, AuNP of 10 nm conjugated with antiCRP-HRP (AuNPâ¢antiCRP-HRP) was used for "capillary ELISA" to detect as low as 0.1 ng/mL of CRP. Also, kinetic study on both 96-well plates and in a capillary tube using antiCRP-HRP or AuNPâ¢antiCRP-HRP showed a synergistic effect between AuNP and the capillary system, in which the fastest assay was observed from the "AuNP capillary ELISA", with its maximum absorbance reaching 2.5 min, while the slowest was the typical well-plate ELISA with its maximum absorbance reaching in 13.5 min.
Subject(s)
Enzyme-Linked Immunosorbent Assay , Antibodies , Gold , Horseradish Peroxidase , Metal NanoparticlesABSTRACT
A novel highly sensitive dendrimer coupled impedimetric immunosensor was developed for the label-free and reagent-free detection of cardiac troponin I (TnI) in serum samples. The immunosensor probe was fabricated by covalently attaching carboxylic acid-functionalized third generation (G3) poly (amidoamine) (PAMAM) dendrimer (Den) on the 3, 3', 5, 5'-tetramethyl benzidine (TMB) modified 6-mercaptohexanoic acid (MHA) self-assembled monolayer (SAM) on a gold (Au) electrode. Monoclonal anti-TnI antibody was then covalently immobilized on the Den and TMB attached MHA SAM modified surface. TMB was used as an internal surface redox couple for generating signal which also allowed to avoid the use of an external one (i.e. ferricyanide couple) in solution during the impedance measurement for monitoring the antibody-antigen binding. On the other hand, Den was used as a signal enhancer by immobilizing more anti-body on the immunosensor probe. The immunosensor probe was characterized using X-ray photoelectron spectroscopy (XPS), quartz crystal microbalance (QCM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) techniques. The TnI detection in diluted serum was based on the measurement of charge transfer resistance (Rct) of the electron transfer process of the surface-attached TMB before and after immunobinding. Under the optimized condition, the proposed immunosensor could detect human TnI in diluted serum samples as low as 11.7 fM with a wide linear dynamic range, good stability, and excellent specificity. The validity of the proposed method was tested in various TnI spiked human undiluted serum samples and was compared with the enzyme-linked immunosorbent assay (ELISA). The results suggested that the proposed immunosensor could be a useful tool for practical applications in clinical diagnosis.
Subject(s)
Antibodies, Immobilized/chemistry , Benzidines/chemistry , Biosensing Techniques/methods , Dendrimers/chemistry , Dielectric Spectroscopy/methods , Troponin I/blood , Biosensing Techniques/instrumentation , Dielectric Spectroscopy/instrumentation , Electrodes , Equipment Design , Gold/chemistry , Humans , Immunoassay/instrumentation , Immunoassay/methods , Limit of DetectionABSTRACT
An ultrasensitive electrochemical nanostructured immunosensor for a breast cancer biomarker carbohydrate antigen 15-3 (CA 15-3) was fabricated using non-covalent functionalized graphene oxides (GO/Py-COOH) as sensor probe and multiwalled carbon nanotube (MWCNTs)-supported numerous ferritin as labels. The immunosensor was constructed by immobilizing a monoclonal anti-CA 15-3 antibody on the GO modified cysteamine (Cys) self-assembled monolayer (SAM) on an Au electrode (Au/Cys) through the amide bond formation between the carboxylic acid groups of GO/Py-COOH and amine groups of anti-CA 15-3. Secondary antibody conjugated MWCNT-supported ferritin labels (Ab2-MWCNT-Ferritin) were prepared through the amide bond formation between amine groups of Ab2 and ferritin and carboxylic acid groups of MWCNTs. The detection of CA 15-3 was based on the enhanced bioelectrocatalytic reduction of hydrogen peroxide mediated by hydroquinone (HQ) at the GO/Py-COOH-based sensor probe. The GO/Py-COOH-based sensor probe and Ab2-MWCNT-Ferritin labels were characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscope (SEM), transmission electron microscope (TEM), and x-ray photoelectron spectroscopy (XPS) techniques. Using differential pulse voltammetry (DPV) technique, CA 15-3 can be selectively detected as low as 0.01 ± 0.07 U/mL in human serum samples. Additionally, the proposed CA 15-3 immunosensor showed excellent selectivity and better stability in human serum samples, which demonstrated that the proposed immunosensor has potentials in proteomic researches and diagnostics.
Subject(s)
Biomarkers, Tumor/isolation & purification , Biosensing Techniques , Breast Neoplasms/diagnosis , Mucin-1/isolation & purification , Nanotubes, Carbon/chemistry , Biomarkers, Tumor/genetics , Breast Neoplasms/pathology , Electrochemical Techniques , Ferritins/chemistry , Graphite/chemistry , Humans , Hydrogen Peroxide/chemistry , Limit of Detection , Metal Nanoparticles/chemistry , Mucin-1/genetics , Oxides/chemistry , ProteomicsABSTRACT
A stimulated mass enhancement strategy based on enormous biocatalytic precipitation of 4-chloro-1-naphthol using magnetic bead-supported horseradish peroxidase and glucose oxidase bienzymes was developed for the highly sensitive detection of interleukin-6 in serum using a quartz crystal microbalance technique.
Subject(s)
Interleukin-6/blood , Quartz Crystal Microbalance Techniques/methods , Biosensing Techniques , Enzymes, Immobilized/metabolism , Glucose Oxidase/metabolism , Horseradish Peroxidase/metabolism , Humans , Limit of Detection , Magnetics/methods , Naphthols/metabolismABSTRACT
A highly sensitive electrochemical carcinoembryonic antigen (CEA) immunosensor was fabricated by covalently immobilizing a monoclonal CEA antibody (anti-CEA, Ab(1)) and a mediator (thionine, Th) on a gold nanoparticle (AuNP)-encapsulated dendrimer (Den/AuNP). Multiwalled carbon nanotube (MWCNT)-supported secondary antibody (Ab(2))-conjugated multiple bienzymes, glucose oxidase (GOx), and horseradish peroxidase (HRP) (Ab(2)/MWCNT/GOx/HRP) were used as electrochemical labels. The highly sensitive detection was achieved by the increased HRP-electrocatalyzed reduction of hydrogen peroxide, which was locally generated by the enzyme GOx. The immunosensor surface was characterized using electrochemical impedance spectroscopy, atomic force microscopy, and quartz crystal microbalance techniques. The Den/AuNP and Ab(2)/MWCNT/GOx/HRP bioconjugates were characterized using high-resolution transmission electron microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. Cyclic voltammetry and square wave voltammetry techniques were used to monitor the increased electrocatalyzed reduction of hydrogen peroxide by HRP. The linear dynamic range and the detection limit were determined to be 10.0 pg/mL to 50.0 ng/mL and 4.4 ± 0.1 pg/mL, respectively. The validity of the immunosensor response was tested in various CEA-spiked human serum samples, and the results were compared to those of an enzyme-linked immunosorbent assay method.