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BMC Oral Health Nov 2021The present study aims to evaluate the effectiveness of mineral trioxide aggregate (MTA) application in treating dens evaginatus affected teeth with apical lesions and...
BACKGROUND
The present study aims to evaluate the effectiveness of mineral trioxide aggregate (MTA) application in treating dens evaginatus affected teeth with apical lesions and open apices using haemostatic collagen membrane to prevent the apical extrusion of MTA.
METHODS
Twelve patients with 14 dens evaginatus affected teeth with apical lesions and open apices were treated with MTA apical plug and haemostatic collagen membrane. Clinical symptoms of subjective pain, pain of palpation, percussion, sinus tract, and the apical lesions' radiographic parameter were recorded at every 3-month interval up to 9 months after treatment. Paired t-test or Wilcoxon signed-rank test was used for statistical analysis with P < 0.05 as the threshold for considering results to be statistically significant.
RESULTS
No patient experienced clinical symptoms 3 months after endodontic treatment. In addition, there was a significant difference in the dimensions of the apical lesions' before compared to 3 months after endodontic treatment.
CONCLUSIONS
The combination of MTA apical plug and haemostatic collagen membrane effectively treated dens evaginatus affected teeth with apical lesions, and open apices.
Topics: Aluminum Compounds; Calcium Compounds; Drug Combinations; Humans; Oxides; Root Canal Filling Materials; Silicates; Tooth Apex
PubMed: 34749689
DOI: 10.1186/s12903-021-01920-6 -
Proceedings of the National Academy of... Oct 2023In various epithelial tissues, the epithelial monolayer acts as a barrier. To fulfill its function, the structural integrity of the epithelium is tightly controlled....
In various epithelial tissues, the epithelial monolayer acts as a barrier. To fulfill its function, the structural integrity of the epithelium is tightly controlled. When normal epithelial cells detach from the basal substratum and delaminate into the apical lumen, the apically extruded cells undergo apoptosis, which is termed anoikis. In contrast, transformed cells often become resistant to anoikis and able to survive and grow in the apical luminal space, leading to the formation of multilayered structures, which can be observed at the early stage of carcinogenesis. However, the underlying molecular mechanisms still remain elusive. In this study, we first demonstrate that S100A10 and ANXA2 (Annexin A2) accumulate in apically extruded, transformed cells in both various cell culture systems and murine epithelial tissues in vivo. ANXA2 acts upstream of S100A10 accumulation. Knockdown of ANXA2 promotes apoptosis of apically extruded RasV12-transformed cells and suppresses the formation of multilayered epithelia. In addition, the intracellular reactive oxygen species (ROS) are elevated in apically extruded RasV12 cells. Treatment with ROS scavenger Trolox reduces the occurrence of apoptosis of apically extruded ANXA2-knockdown RasV12 cells and restores the formation of multilayered epithelia. Furthermore, ROS-mediated p38MAPK activation is observed in apically delaminated RasV12 cells, and ANXA2 knockdown further enhances the p38MAPK activity. Moreover, the p38MAPK inhibitor promotes the formation of multilayered epithelia of ANXA2-knockdown RasV12 cells. These results indicate that accumulated ANXA2 diminishes the ROS-mediated p38MAPK activation in apically extruded transformed cells, thereby blocking the induction of apoptosis. Hence, ANXA2 can be a potential therapeutic target to prevent multilayered, precancerous lesions.
Topics: Animals; Mice; Annexin A2; Apoptosis; Epithelial Cells; Epithelium; Reactive Oxygen Species
PubMed: 37844241
DOI: 10.1073/pnas.2307118120 -
Journal of Virology Feb 2019Hepatitis E virus (HEV) is a common cause of acute viral hepatitis worldwide. Most HEV infections are asymptomatic, but immunocompromised patients infected with HEV...
Hepatitis E virus (HEV) is a common cause of acute viral hepatitis worldwide. Most HEV infections are asymptomatic, but immunocompromised patients infected with HEV genotype 3 (HEV3), HEV4, or HEV7 may develop chronic infections. The HEV particles in stools are naked (nHEV), while those in the serum and culture supernatants (eHEV) are associated with lipids. Hepatocytes are polarized epithelial cells that have basolateral (oriented toward the blood) and apical (oriented toward the bile) exosomal pathways. We isolated a subclone, F2, from the human hepatocarcinoma cell line HepG2/C3A that grew as a polarized monolayer culture and had better HEV production than HepG2/C3A cells. F2 cells cultured on semipermeable collagen inserts and infected basolaterally with nHEV3 released 94.6% of virus particles apically, those infected with eHEV3 released 96.8% apically, and eHEV1-infected cells released 99.3% apically. Transcytosis was not involved. Density gradient centrifugation and NP-40 treatment showed that HEV particles released both apically and basolaterally were lipid associated. The apically released HEV3 and HEV1 particles were six and nine times more infectious than those released basolaterally, respectively. Confocal microscopy indicated that the open reading frame 2 (ORF2) capsid protein colocalized apically with ORF3 virus protein, the apical marker DPP4, and the recycling endosome GTPase Rab27a. The amounts of soluble glycosylated ORF2 secreted apically and basolaterally were similar. These polarized-hepatocyte data suggest that infectious HEV particles are mainly released into bile, while the small fraction released into blood could spread HEV throughout the host. Hepatitis E virus (HEV) in stools is naked, while that in culture supernatants and patients' blood is lipid associated. Its life cycle in hepatocytes, polarized cells with a basolateral side communicating with blood and an apical side connected with bile, is incompletely understood. We have developed a polarized hepatocyte model and used the cells to analyze the supernatants bathing the apical and basolateral sides and HEV subcellular distribution. HEV particles from both sides were lipid associated, and most infectious HEV particles left the cell via its apical side. Similar amounts of the open reading frame 2 (ORF2) soluble capsid protein were secreted from both sides of the hepatocytes. This model mimicking physiological conditions should help clarify the HEV cell cycle in polarized hepatocytes.
Topics: Capsid Proteins; Carcinoma, Hepatocellular; Cell Culture Techniques; Cell Line; Cell Polarity; Epithelial Cells; Hep G2 Cells; Hepatitis E; Hepatitis E virus; Hepatocytes; Humans; Liver Neoplasms; Serum; Viral Proteins; Virus Release
PubMed: 30463960
DOI: 10.1128/JVI.01207-18 -
Archives of Pathology & Laboratory... Oct 2015The pulmonary apical cap (PAC) is a morphologically distinct type of unilateral or bilateral fibroelastotic scar involving the lung apices. Despite being relatively... (Review)
Review
The pulmonary apical cap (PAC) is a morphologically distinct type of unilateral or bilateral fibroelastotic scar involving the lung apices. Despite being relatively common and having been described more than a hundred years ago, it remains underappreciated as a unique diagnostic entity by clinicians, radiologists, and pathologists alike. Given the centrality of modern chest imaging in the workup of diseases of the lungs, it may be expected that the PAC will be biopsied with increasing frequency. As such, pathologists should be familiar with its presentation, appearance, and differential diagnosis. This article serves as a short overview of PAC and as a practical aid in its diagnosis for surgical pathologists.
Topics: Cicatrix; Diagnosis, Differential; Humans; Lung; Lung Diseases; Lung Neoplasms; Radiography, Thoracic; Tomography, X-Ray Computed
PubMed: 26414471
DOI: 10.5858/arpa.2015-0224-RA -
Annals of Botany Dec 2022Aquatic carnivorous plants have typical rootless linear shoots bearing traps and exhibit steep physiological polarity with rapid apical growth. The aim was to analyse...
BACKGROUND AND AIMS
Aquatic carnivorous plants have typical rootless linear shoots bearing traps and exhibit steep physiological polarity with rapid apical growth. The aim was to analyse auxin and cytokinin metabolites in traps, leaves/shoots and shoot apices in several species of genera Aldrovanda and Utricularia to elucidate how the hormonal profiles reflect the specific organ functions and polarity.
METHODS
The main auxin and cytokinin metabolites were analysed in miniature samples (>2 mg dry weight) of different organs of Aldrovanda vesiculosa and six Utricularia species using ultraperformance liquid chromatography coupled with triple quadrupole mass spectrometry.
KEY RESULTS
Total contents of biologically active forms (free bases, ribosides) of all four main endogenously occurring cytokinin types were consistently higher in traps than in leaves in four Utricularia species with monomorphic shoots and/or higher than in shoots in two Utricularia species with dimorphic shoots. In Aldrovanda traps, the total content of different cytokinin forms was similar to or lower than that in shoots. In U. australis leaves, feeding on prey increased all cytokinin forms, while no consistent differences occurred in Aldrovanda. In four aquatic Utricularia species with monomorphic shoots, the content of four auxin forms was usually higher in traps than in leaves. Zero IAA content was determined in U. australis leaves from a meso-eutrophic site or when prey-fed.
CONCLUSIONS
Different cytokinin and auxin profiles estimated in traps and leaves/shoots of aquatic carnivorous plants indicate an association with different dominant functions of these organs: nutrient uptake by traps versus photosynthetic function of traps. Interplay of cytokinins and auxins regulates apical dominance in these plants possessing strong polarity.
Topics: Cytokinins; Carnivorous Plant; Indoleacetic Acids; Magnoliopsida; Droseraceae; Lamiales
PubMed: 36215097
DOI: 10.1093/aob/mcac122 -
Restorative Dentistry & Endodontics May 2021The aim of this study was to evaluate the shaping ability of the TruShape and Reciproc Blue systems and the apical extrusion of debris after root canal instrumentation....
OBJECTIVES
The aim of this study was to evaluate the shaping ability of the TruShape and Reciproc Blue systems and the apical extrusion of debris after root canal instrumentation. The ProTaper Universal system was used as a reference for comparison.
MATERIALS AND METHODS
Thirty-three mandibular premolars with a single canal were scanned using micro-computed tomography and were matched into 3 groups ( = 11) according to the instrumentation system: TruShape, Reciproc Blue and ProTaper Universal. The teeth were accessed and mounted in an apparatus with agarose gel, which simulated apical resistance provided by the periapical tissue and enabled the collection of apically extruded debris. During root canal preparation, 2.5% sodium hypochlorite was used as an irrigant. The samples were scanned again after instrumentation. The percentage of unprepared area, removed dentin, and volume of apically extruded debris were analyzed. The data were analyzed using 1-way analysis of variance and the Tukey test for multiple comparisons at a 5% significance level.
RESULTS
No significant differences in the percentage of unprepared area were observed among the systems ( > 0.05). ProTaper Universal presented a higher percentage of dentin removal than the TruShape and Reciproc Blue systems ( < 0.05). The systems produced similar volumes of apically extruded debris ( > 0.05).
CONCLUSIONS
All systems caused apically extruded debris, without any significant differences among them. TruShape, Reciproc Blue, and ProTaper Universal presented similar percentages of unprepared area after root canal instrumentation; however, ProTaper Universal was associated with higher dentin removal than the other systems.
PubMed: 34123752
DOI: 10.5395/rde.2021.46.e16 -
Frontiers in Cell and Developmental... 2021Integrins are transmembrane proteins that are most typically thought of as integrating adhesion to the extracellular matrix with intracellular signaling and cell... (Review)
Review
Integrins are transmembrane proteins that are most typically thought of as integrating adhesion to the extracellular matrix with intracellular signaling and cell regulation. Traditionally, integrins are found at basolateral and lateral cell surfaces where they facilitate binding to the ECM and intercellular adhesion through cytosolic binding partners that regulate organization of actin microfilaments. However, evidence is accumulating that integrins also are apically localized, either endogenously or due to an exogenous stimulus. Apically localized integrins have been shown to regulate several processes by interacting with proteins such as connexins, tight junction proteins, and polarity complex proteins. Integrins can also act as receptors to mediate endocytosis. Here we review these newly appreciated roles for integrins localized to the apical cell surface.
PubMed: 34485286
DOI: 10.3389/fcell.2021.699407 -
Current Opinion in Cell Biology Oct 2021Epithelial cells use the process of extrusion to promote cell death while preserving a tight barrier. To extrude, a cell and its neighbors contract actin and myosin... (Review)
Review
Epithelial cells use the process of extrusion to promote cell death while preserving a tight barrier. To extrude, a cell and its neighbors contract actin and myosin circumferentially and basolaterally to seamlessly squeeze it out of the epithelium. Recent research highlights how early apical pulsatile contractions within the extruding cell might orchestrate contraction in three dimensions so that a cell extrudes out apically. Along with apical constrictions, studies of ion channels and mathematical modeling reveal how differential contraction between cells helps select specific cells to extrude. In addition, several studies have offered new insights into pathways that use extrusion to eliminate transformed cells or cause an aberrant form of extrusion that promotes cell invasion.
Topics: Actins; Epithelial Cells; Epithelium; Humans; Neoplasms; Signal Transduction
PubMed: 34034216
DOI: 10.1016/j.ceb.2021.04.005 -
American Journal of Physiology. Renal... Oct 2006The maintenance of apical and basolateral membrane domains with distinct protein and lipid compositions is necessary for the proper function of polarized epithelial... (Review)
Review
The maintenance of apical and basolateral membrane domains with distinct protein and lipid compositions is necessary for the proper function of polarized epithelial cells. Delivery of cargo to the basolateral surface is thought to be mediated by the interaction of cytoplasmically disposed sorting signals with sorting receptors, whereas apically destined cargoes are sorted via mechanisms dependent on cytoplasmic, glycan-mediated, or lipid-interacting sorting signals. Apical and basolateral cargo are delivered to the surface in discrete tubular and vesicular carriers that bud from the trans-Golgi network (TGN). While it has long been thought that the TGN is the primary compartment in which apical and basolateral cargoes are segregated, recent studies suggest that sorting may begin earlier along the biosynthetic pathway. Moreover, rather than being delivered directly from the TGN to the cell surface, at least a subset of biosynthetic cargo appears to transit recycling endosomes en route to the plasma membrane. The implications and limitations of these challenges to the conventional model for how proteins are sorted and trafficked along the biosynthetic pathway are discussed.
Topics: Animals; Biological Transport; Cytoplasm; Endocytosis; Epithelial Cells; Kidney; Signal Transduction; trans-Golgi Network
PubMed: 16788143
DOI: 10.1152/ajprenal.00161.2006 -
Frontiers in Cell and Developmental... 2021The inner/apical surface of the embryonic brain wall is important as a major site for cell production by neural progenitor cells (NPCs). We compared the mechanical...
The inner/apical surface of the embryonic brain wall is important as a major site for cell production by neural progenitor cells (NPCs). We compared the mechanical properties of the apical surfaces of two neighboring but morphologically distinct cerebral wall regions in mice from embryonic day (E) E12-E14. Through indentation measurement using atomic force microscopy (AFM), we first found that Young's modulus was higher at a concave-shaped apical surface of the pallium than at a convex-shaped apical surface of the ganglionic eminence (GE). Further AFM analysis suggested that contribution of actomyosin as revealed with apical surface softening by blebbistatin and stiffness of dissociated NPCs were both comparable between pallium and GE, not accounting for the differential apical surface stiffness. We then found that the density of apices of NPCs was greater, with denser F-actin meshwork, in the apically stiffer pallium than in GE. A similar correlation was found between the decreasing density between E12 and E14 of NPC apices and the declining apical surface stiffness in the same period in both the pallium and the GE. Thus, one plausible explanation for the observed difference (pallium > GE) in apical surface stiffness may be differential densification of NPC apices. In laser ablation onto the apical surface, the convex-shaped GE apical surface showed quicker recoils of edges than the pallial apical surface did, with a milder inhibition of recoiling by blebbistatin than in pallium. This greater pre-stress in GE may provide an indication of how the initially apically concave wall then becomes an apically convex "eminence."
PubMed: 34368153
DOI: 10.3389/fcell.2021.702068