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TheScientificWorldJournal Feb 2011There are different nail manifestations of systemic diseases. This case represents Mees' lines. In the current report, this phenomenon was caused by chemotherapy agents...
There are different nail manifestations of systemic diseases. This case represents Mees' lines. In the current report, this phenomenon was caused by chemotherapy agents used for treatment of leukemia. It was caused by medication insult to the nail matrix. Nonblanching and impalpable nail bands, migration with the nail growth, and thumb involvement differentiate Mees' from Beau's and Muehrcke's lines.
Topics: Adult; Humans; Male; Nail Diseases
PubMed: 21298217
DOI: 10.1100/tsw.2011.27 -
Scientific Reports Sep 2022We elucidate the band structures and scattering properties of the simplest one-dimensional parity-time ([Formula: see text])-symmetric photonic crystal. Its unit cell...
We elucidate the band structures and scattering properties of the simplest one-dimensional parity-time ([Formula: see text])-symmetric photonic crystal. Its unit cell comprises one gain layer and one balanced loss layer. Herein, the analytic expressions of the band structures and scattering properties are derived, and based on these relations, we reveal and explain the following phenomena: Exceptional point pairs appear from Brillouin boundaries at a nonzero non-Hermiticity. With an increase in non-Hermiticity, each of these pairs moves toward the Brillouin center, finally coalescing into a single point at the Brillouin center at a critical non-Hermiticity value. Near the exceptional point, singular scattering is observed and explained. This refers to the phenomenon whereby transmittances and reflectances for left and right incidences reach exceptionally large values simultaneously. Moreover, these are infinite at some discrete points at which poles and zeros of the scattering matrix are attained. In forbidden gaps, unidirectional weak visibility, where transmittances are zero, is disclosed and analyzed: specifically, the reflectance for incidence from one side is very large, whereas that for incidence from the other side is very small. In this phenomenon, the eigenstates of the scattering matrix are the incident waves from the left and right sides, and their eigenvalues are the corresponding reflectances. Our results are important as new functional optical devices can potentially be developed by utilizing these novel phenomena.
PubMed: 36167897
DOI: 10.1038/s41598-022-20559-z -
Methods in Molecular Biology (Clifton,... 2021Electrophoretic mobility shift assays (EMSAs) are among the most frequently used and straightforward experiments for studying protein-nucleic acid interactions. EMSAs...
Electrophoretic mobility shift assays (EMSAs) are among the most frequently used and straightforward experiments for studying protein-nucleic acid interactions. EMSAs rely on the principle that protein-nucleic acid complexes have reduced electrophoretic mobility in a native gel matrix compared to free nucleic acid due to their larger size and reduced negative charge. Therefore, bands for the protein-nucleic acid complexes are shifted in a gel and can be distinguished from free nucleic acids. EMSAs remain a popular technique since they do not require specialist equipment and the complexes formed are easily visualized. Furthermore, the technique can be adapted to enable various aspects of protein-nucleic acid interactions to be investigated, including sequence specificity, estimated binding affinity, and binding stoichiometry.
Topics: Acrylic Resins; Biophysical Phenomena; DNA; Electrophoretic Mobility Shift Assay; Nucleic Acids; Protein Binding; Proteins; RNA
PubMed: 33877605
DOI: 10.1007/978-1-0716-1197-5_14 -
Morphologie : Bulletin de L'Association... Feb 2021The development of the myocardial band shows that it starts and ends at the origin of the great vessels and that the myocardium joins to these rings but does not...
OBJECTIVE
The development of the myocardial band shows that it starts and ends at the origin of the great vessels and that the myocardium joins to these rings but does not inserted into them. We always considered that there should be a fixed end of the muscle band that would allow it a helical rotation to fulfill its fundamental movements of shortening-torsion (systole) and elongation-distortion (suction).
MATERIAL AND METHODS
Seven young-bovine hearts (800-1000g) and seven human hearts (one embryo, 4g; one 10 years, 250g and five adult, 300g/average) were used for a detailed macrocoscopic and microscopic study.
RESULTS
We have found in all the bovine and human hearts studied a nucleus underlying the right trigone, whose osseus, chondroid or tendinous histological structure depends on the specimen analyzed. The microscopic analysis revealed in the hearts a trabecular osteochondral matrix (fulcrum) with segmental lines in bovines and in the ten-year-old human. In the fetus, it was found pre-chondroid areas in a myxoid stroma. In the adult human hearts, the histological analysis revealed a matrix similar to that of a tendon. All the hearts studied presented myocardial attachment to the rigid structure of the fulcrum. Myocardiocytes were not found neither at the left or rigth trigonous nor at the base of the valves.
CONCLUSIONS
The finding of the fulcrum gives support to the spiral myocardial band being the point of fixation that allows the helicoidal torsion.
Topics: Adult; Animals; Cattle; Child; Heart Ventricles; Humans; Myocardium; Rotation; Systole
PubMed: 32646845
DOI: 10.1016/j.morpho.2020.06.010 -
Journal of Oral Science Oct 2021To evaluate the influence of the restorative material and matrix system on proximal contact tightness and morphological characteristics of class II restorations in...
PURPOSE
To evaluate the influence of the restorative material and matrix system on proximal contact tightness and morphological characteristics of class II restorations in primary molars.
METHODS
Occluso-mesial cavities in second primary artificial molars were randomly restored using different materials (Filtek Z500 or Filtek Bulk Fill composites or high-viscosity glass ionomer cement Ketac Universal) and different matrix system (Tofflemire, AutoMatrix, matrix band with ring, contoured sectional matrix) (n = 12). Proximal contact tightness was measured using a custom-made device in an Instron 3345, and proximal surface morphology and marginal adaptation were scored after digital scanning. Two-way ANOVA, Tukey and Fischer's exact tests were performed (P < 0.05).
RESULTS
Proximal contact tightness values were significantly influenced by the restorative material (P < 0.05), the matrix system (P < 0.001), and their interaction (P < 0.01). Both resin composites showed statistically differences in proximal shape according to the matrix used to restore and exhibited overhanging margins. Ketac Universal restorations showed similar morphology and gaps on the margins regardless of the matrix system.
CONCLUSIONS
Overall, both composite restorations achieved tighter proximal contact than those restored with the high-viscosity glass ionomer cement. None of the matrix systems tested provided a convex seamless proximal morphology.
Topics: Dental Materials; Glass Ionomer Cements; Molar; Tooth, Deciduous; Viscosity
PubMed: 34511588
DOI: 10.2334/josnusd.21-0264 -
Cureus Jan 2022This study aimed to investigate the operator's ease, satisfaction, and comfort of using a circumferential matrix system and sectional matrix system on the proximal...
OBJECTIVES
This study aimed to investigate the operator's ease, satisfaction, and comfort of using a circumferential matrix system and sectional matrix system on the proximal contact points and contours when restoring class II cavities in posterior teeth.
MATERIALS AND METHODS
This cross-sectional study was performed at the clinics in the Department of Conservative Dental Sciences, College of Dentistry, Qassim University. A total of 105 dental students randomly participated in this study to restore a class II cavity with direct composite resin restoration. Operators' comfort and satisfaction were evaluated according to their assessment of the contact points they reproduced and the emergence profiles of restorations, using a circumferential matrix system and sectional matrix system.
RESULTS
Out of 105 operators, 57 were satisfied with using circumferential matrix bands for most of their cases while 78 of the operators were satisfied with sectional matrix bands. There were no significant differences between operator satisfaction and the use of circumferential matrix band system (P > 0.05) and sectional matrix band system (P = 0.134) but there was a significant difference between difficulty levels in the use of both matrix band systems (P < 0.05; P = 0.000).
CONCLUSION
Circumferential and sectional matrix band systems showed no significant differences with operators' satisfaction during restoring class II cavities in posterior teeth but using a sectional matrix band system was considered easier than using a circumferential matrix band system.
PubMed: 35004091
DOI: 10.7759/cureus.20957 -
British Dental Journal Nov 2021Sectional matrix techniques offer more predictable solutions to achieving contact areas when placing direct interproximal posterior composites than circumferential...
Sectional matrix techniques offer more predictable solutions to achieving contact areas when placing direct interproximal posterior composites than circumferential matrix techniques, resulting in reduced reported complaints of food packing from patients. Despite this, a large majority of UK dentists and therapists don't currently use them. Sectional matrix systems are technique-sensitive to use, which can be a barrier to implementation for inexperienced users. The matrices can easily distort during their placement and stabilisation and when placing the restorative material. This can result in unwanted, clinically relevant problems in the resulting restorations, some of which may not be discernible once they have occurred. This paper explores the advantages and disadvantages of sectional matrices and the processes and techniques involved in their use, before discussing the potential for distortion at each step. It offers solutions to some of the commonly seen problems which will provide more predictable outcomes for those already using these techniques and encourage non-users to add them to their armamentarium.
Topics: Composite Resins; Dental Cavity Preparation; Dental Materials; Dental Restoration, Permanent; Humans; Matrix Bands
PubMed: 34773017
DOI: 10.1038/s41415-021-3608-5 -
Nature Communications Mar 2023Casparian strips (CS) are aligned bands of lignin-impregnated cell walls, building an extracellular diffusion barrier in roots. Their structure profoundly differs from...
Casparian strips (CS) are aligned bands of lignin-impregnated cell walls, building an extracellular diffusion barrier in roots. Their structure profoundly differs from tight junctions (TJ), analogous structures in animals. Nonetheless, CS membrane domain (CSD) proteins 1-5 (CASP1-5) are homologues of occludins, TJ components. CASP-marked membranes display cell wall (matrix) adhesion and membrane protein exclusion. A full CASP knock-out now reveals CASPs are not needed for localized lignification, since correctly positioned lignin microdomains still form in the mutant. Ultra-structurally, however, these microdomains are disorganized, showing excessive cell wall growth, lack of exclusion zone and matrix adhesion, and impaired exocyst dynamics. Proximity-labelling identifies a Rab-GTPase subfamily, known exocyst activators, as potential CASP-interactors and demonstrate their localization and function at the CSD. We propose that CASP microdomains displace initial secretory foci by excluding vesicle tethering factors, thereby ensuring rapid fusion of microdomains into a membrane-cell wall band that seals the extracellular space.
Topics: Arabidopsis Proteins; Arabidopsis; Lignin; Cell Membrane; Biological Transport
PubMed: 36959183
DOI: 10.1038/s41467-023-37265-7 -
International Journal of Clinical... 2021To compare two matrix systems (circumferential and sectional) based on clinical efficiency and patient acceptability for placement of visible light cure composite resin...
Comparative Evaluation of Clinical Efficiency and Patient Acceptability toward the Use of Circumferential Matrix and Sectional Matrix for Restoration of Class II Cavities in Primary Molars: An Study.
AIM
To compare two matrix systems (circumferential and sectional) based on clinical efficiency and patient acceptability for placement of visible light cure composite resin restorative material in a Class II cavity in primary molars.
MATERIALS AND METHODS
Thirty children with bilateral Class II cavities of age-group 5-9 years were selected. A split-mouth comparative experimental study was conducted at Manav Rachna Dental College, India. Cavities were restored using either circumferential or sectional matrix band system. The child upon completion of the treatment filled the subject preference questionnaire. Time assessment was done for matrix system placement. Contact points were evaluated using dental floss as open or closed.
RESULTS
Time required to place sectional matrices was more (125.30 ± 29.40) than required for circumferential matrices (117.20 ± 38.94). The sectional matrices group has more ideal contacts (23) (76.7%) than the circumferential matrices group (16) (53.3%). About 70% of the children pointed discomfort toward the sectional matrices. Children in this study accepted circumferential matrices to be more comfortable than the sectional matrices group.
CONCLUSION
The circumferential matrices group was more time efficient compared to the sectional matrices group. However, sectional matrices resulted in a greater number of restorations with ideal contacts. Based on the preference circumferential matrix band system has been found superior to sectional matrix band system.
CLINICAL SIGNIFICANCE
This study was conducted to find a better matrix system in case of pediatric patients. Circumferential matrices were found to be more superior with respect to preference and time efficiency and sectional matrices were preferred for ideal contacts.
HOW TO CITE THIS ARTICLE
Bhatia HP, Sood S, Sharma N, Comparative Evaluation of Clinical Efficiency and Patient Acceptability toward the Use of Circumferential Matrix and Sectional Matrix for Restoration of Class II Cavities in Primary Molars: An In Vivo Study. Int J Clin Pediatr Dent 2021;14(6):748-751.
PubMed: 35110865
DOI: 10.5005/jp-journals-10005-2060 -
Frontiers in Dentistry 2023Hardness is relevant to the degree of conversion (DC) and depth of cure (DoC). The aim of this study was to determine the micro-hardness and DoC of conventional and...
Hardness is relevant to the degree of conversion (DC) and depth of cure (DoC). The aim of this study was to determine the micro-hardness and DoC of conventional and bulk-fill composite resins in class II restorations using metal and clear matrix bands. Twelve specimens of each of the two composite resins, , Filtek Z350 XT bulk-fill and Gradia posterior conventional composite, were prepared in the form of a class II cavity in a tooth mold, using a clear or metal matrix band. All specimens were cured and stored at 37°C for 24 hours. Vickers hardness was measured as a function of DoC at 2mm intervals. Data were analyzed by two-way ANOVA (alpha=0.05). The bulk-fill composite exhibited significantly higher hardness levels than the conventional composite in all tested surfaces (P<0.001). However, while the metal matrix band had a significant impact on the bottom surface (P=0.059) and also on the furthest surface from the matrix and light source (P=0.04), it did not have a consistent effect across all tested surfaces. The simultaneous interaction of the composites and matrix band types in all surfaces, did not show significant differences in hardness values. The highest bottom-to-top surface hardness ratio (73%) was observed in the conventional composite near the metal matrix band. In deep class II cavities, the bottom-to-top surface hardness ratio did not reach the maximum of 80%, neither for bulk-fill nor conventional posterior composites. Therefore, in such cavities extended light-curing and more incremental composite placement is needed.
PubMed: 37701657
DOI: 10.18502/fid.v20i20.12912