The Biochemical and Molecular Analysis of Changes in Melanogenesis Induced by UVA-Activated Fluoroquinolones—In Vitro Study on Human Normal Melanocytes

Fluoroquinolones cause phototoxic reactions, manifested as different types of skin lesions, including hyperpigmentation. The disturbances of melanogenesis indicate that fluoroquinolones may affect cellular processes in melanocytes. It has been reported that these antibiotics may bind with melanin and accumulate in pigmented cells. The study aimed to examine the changes in melanogenesis in human normal melanocytes exposed to UVA radiation and treated with lomefloxacin and moxifloxacin, the most and the least fluoroquinolone, respectively. The obtained results demonstrated that both tested fluoroquinolones inhibited melanogenesis through a decrease in tyrosinase activity and down-regulation of tyrosinase and microphthalmia-associated transcription factor production. Only lomefloxacin potentiated UVA-induced melanogenesis. Under UVA irradiation lomefloxacin significantly enhanced melanin content and tyrosinase activity in melanocytes, although the drug did not cause an increased expression of tyrosinase or microphthalmia-associated transcription factor. The current studies revealed that phototoxic activity of fluoroquinolones is associated with alterations in the melanogenesis process. The difference in phototoxic potential of fluoroquinolones derivatives may be connected with various effects on UVA-induced events at a cellular level.

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Comparison of Fracture Resistance in Thermal and Self-Curing Acrylic Resins—An In Vitro Study

Polymers ◽

10.3390/polym13081234 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1234

Author(s):

António Sérgio Silva ◽

Aurora Carvalho ◽

Pedro Barreiros ◽

Juliana de Sá ◽

Carlos Aroso ◽

...

Keyword(s):

Fracture Resistance ◽

Research Work ◽

Testing Machine ◽

In Vitro Study ◽

Dimensional Accuracy ◽

Acrylic Resin ◽

Thermosetting Resins ◽

Acrylic Resins ◽

The Difference

Thermal and self-curing acrylic resins are frequently and versatilely used in dental medicine since they are biocompatible, have no flavor or odor, have satisfactory thermal qualities and polishing capacity, and are easy and fast. Thus, given their widespread use, their fracture resistance behavior is especially important. In this research work, we comparatively analyzed the fracture resistance capacity of thermo and self-curing acrylic resins in vitro. Materials and Methods: Five prosthesis bases were created for each of the following acrylic resins: Lucitone®, ProBase®, and Megacryl®, which were submitted to different forces through the use of the CS® Dental Testing Machine, usually mobilized in the context of fatigue tests. To this end, a point was defined in the center of the anterior edge of the aforementioned acrylic resin bases, for which the peak tended until a fracture occurred. Thermosetting resins were, on average, more resistant to fracture than self-curable resins, although the difference was not statistically significant. The thermosetting resins of the Lucitone® and Probase® brands demonstrated behavior that was more resistant to fracture than the self-curing homologues, although the difference was not statistically significant. Thermosetting resins tended to be, on average, more resistant to fracture and exhibited the maximum values for impact strength, compressive strength, tensile strength, hardness, and dimensional accuracy than self-curing resins, regardless of brand.

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Effect of Citric Acid on Color Changes of Calcium Silicate-Based Cements an In Vitro Study

Applied Sciences ◽

10.3390/app11052339 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2339

Author(s):

Joanna Metlerska ◽

Till Dammaschke ◽

Mariusz Lipski ◽

Irini Fagogeni ◽

Anna Machoy-Mokrzyńska ◽

...

Keyword(s):

Citric Acid ◽

Calcium Silicate ◽

In Vitro Study ◽

Vitro Study ◽

Color Measurement ◽

Color Changes ◽

Naked Eye ◽

Root Canal Irrigants ◽

The Difference

The aim of the present in vitro study was to investigate the effects of 10% and 40% citric acid (CA) on the color of calcium silicate–based cements (CSCs) in comparison to the effects of common root canal irrigants. Samples of six CSCs (n = 6)—ProRoot MTA (Dentsply, Tulsa, OK, USA), Biodentine (Septodont, Saint-Maur-des-Fossés, France), MTA Plus (Avalon Biomed Inc, by Prevest Denpro Limited, Jammu, India), MTA Repair HP (Angelus, Londrina, PR, Brazil), Ortho MTA (BioMTA, Seoul, Korea), and Retro MTA (BioMTA, Seoul, Korea)—were immersed in 10% and 40% CA as well as 15% EDTA, 2% NaOCl, 2% CHX, and 0.9% NaCl for 15 min, 1 h, and 24 h. ΔE values, representing the difference between the final and baseline values of the color components, were then determined using a VITA Easyshade Compact 5.0 spectrophotometer. Naked-eye evaluation of the changes in color and structures of the materials was performed using our own scale. Upon immersion of the materials in both 10% and 40% CA, there were statistically significant differences between spectrophotometric color measurement results for all CSCs (P < 0.05). However, CA does not cause dark discoloration, observable with the naked eye, of any of the materials, such as NaOCl and CHX. Significant statistical differences were also found between all CSCs in terms of submersion duration (P < 0.05). CA, which could be an alternative to EDTA use, caused greater CSCs discoloration and changed some of their structures. Unless required by the therapeutic procedure, clinicians should pay attention to the fact that the irrigant may affect the CSCs discoloration and minimize the contact time of irrigant with CSCs.

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Scanning Accuracy of Bracket Features and Slot Base Angle in Different Bracket Materials by Four Intraoral Scanners: An In Vitro Study

Materials ◽

10.3390/ma14020365 ◽

2021 ◽

Vol 14 (2) ◽

pp. 365

Author(s):

Seon-Hee Shin ◽

Hyung-Seog Yu ◽

Jung-Yul Cha ◽

Jae-Sung Kwon ◽

Chung-Ju Hwang

Keyword(s):

Stainless Steel ◽

In Vitro Study ◽

Sem Images ◽

Polycrystalline Alumina ◽

Base Angle ◽

Accurate Expression ◽

Dental Model ◽

Alumina Composite ◽

The Difference

The accurate expression of bracket prescription is important for successful orthodontic treatment. The aim of this study was to evaluate the accuracy of digital scan images of brackets produced by four intraoral scanners (IOSs) when scanning the surface of the dental model attached with different bracket materials. Brackets made from stainless steel, polycrystalline alumina, composite, and composite/stainless steel slot were considered, which have been scanned from four different IOSs (Primescan, Trios, CS3600, and i500). SEM images were used as references. Each bracket axis was set in the reference scan image, and the axis was set identically by superimposing with the IOS image, and then only the brackets were divided and analyzed. One-way analysis of variance (ANOVA) was used to compare the differences. The difference between the manufacturer’s nominal torque and bracket slot base angle was 0.39 in SEM, 1.96 in Primescan, 2.04 in Trios, and 5.21 in CS3600 (p < 0.001). The parallelism, which is the difference between the upper and lower angles of the slot wall, was 0.48 in SEM, 7.00 in Primescan, 5.52 in Trios, 6.34 in CS3600, and 23.74 in i500 (p < 0.001). This study evaluated the accuracy of the bracket only, and it must be admitted that there is some error in recognizing slots through scanning in general.

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Hypertonic Dextrose Stimulates Chondrogenic Cells to Deposit Collagen and Proliferate

Cartilage ◽

10.1177/19476035211014572 ◽

2021 ◽

pp. 194760352110145

Author(s):

Elisha Johnston ◽

Yi Kou ◽

Jason Junge ◽

Lin Chen ◽

Andrew Kochan ◽

...

Keyword(s):

Metabolic Activity ◽

Polynomial Regression ◽

Second Harmonic ◽

In Vitro Study ◽

Cartilage Regeneration ◽

Collagen Deposition ◽

Cellular Processes ◽

Photon Excitation ◽

Hypertonic Dextrose

Objective Hypertonic dextrose (HD) injections (prolotherapy) for osteoarthritis are reported to reduce pain. Cartilage regeneration is hypothesized as a mechanism. This in vitro study identifies an HD concentration that stimulates chondrogenic cells to increase metabolic activity and assesses whether this concentration affects collagen deposition and proliferation. Design ATDC5 chondrogenic cells were cultured in normoglycemic DMEM/F12 medium, treated with concentrations of HD (4-400 mM), and assessed with PrestoBlue. Advanced light microscopy was used to conduct live imaging of collagen deposition through second harmonic generation microscopy (SHG) and proliferation via 2-photon excitation microscopy. Proliferation was additionally assessed with hemocytometer counts. Results A linear regression model found that, relative to the 4 mM baseline control, cells treated with 200 mM had a higher mean absorbance ( P = 0.023) and cells treated with 250 mM were trending toward a higher mean absorbance ( P = 0.076). Polynomial regression interpolated 240 mM as producing the highest average absorbance. Hemocytometer counts validated 250 mM as stimulating proliferation compared with the 4 mM control ( P < 0.01). A concentration of 250 mM HD led to an increase in collagen deposition compared with that observed in control ( P < 0.05). This HD concentration also led to increases in proliferation of ATDC5 cells relative to that of control ( P < 0.001). Conclusions A 250 mM HD solution appears to be associated with increased metabolic activity of chondrocytes, increased collagen deposition, and increased chondrocyte proliferation. These results support clinical prolotherapy research suggesting that intra-articular HD joint injections reduce knee pain. Further study of HD and cellular processes is warranted.

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EVALUATION OF THE DISSOLVING EFFICACY OF ESSENTIAL OILS ON ENDODONTIC OBTURATING MATERIALS: AN IN VITRO STUDY.

10.36106/ijsr/2402413 ◽

2021 ◽

pp. 66-68

Author(s):

Rakesh Pyla ◽

Jai Kiran Killada ◽

V Raja Sekhar

Keyword(s):

Essential Oils ◽

Epoxy Resin ◽

In Vitro Study ◽

Vitro Study ◽

Lavender Oil ◽

Citronella Oil ◽

Gutta Percha ◽

Lemon Oil ◽

The Difference

Aim:Endodontic retreatment is a procedure that removes the lling materials from the root canals followed by their cleaning, shaping and obturation. This in-vitro study aimed to compare and evaluate the ability of various essential oils as solvents in dissolving gutta-percha, epoxy resin, and zinc oxide eugenol (ZOE) cements. Materials and methods: A total of 28 cylindrical specimens in each group ZOE, epoxy resin, 28 ISO size 40 gutta-percha cones were prepared and divided into four groups for immersion in the different solvents, i.e. lemon oil, citronella oil, lavender oil, and TCE(Tetrachloroethylene (control)) for 5 minutes. The obturating materials dissolution in the solvents were obtained by the difference between the pre-immersion original weight and the post-immersion weight on a digital analytical scale. Data were statistically analysed by a paired t-test and Analysis of Variance (ANOVA) (p < 0.05). Results: Order of efcacy of dissolution of essential oils was found to be lemon oil > Citronella oil > Lavender oil and was highly signicant (p < 0.01). In all the solvents, Gutta-percha showed maximum dissolution (Fvalue:149.56) followed by ZOE(89.07 ) and resin sealer least (23.86). Conclusion: It can be concluded that the lemon oil can be used as a solvent for dissolving obturating materials.

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Comparison of the Remineralizing Effect of Brushing with Aloe vera versus Fluoride Toothpaste

European Journal of Dentistry ◽

10.1055/s-0040-1716597 ◽

2020 ◽

Author(s):

Teresa Al Haddad ◽

Elie Khoury ◽

Nada Farhat Mchayleh

Keyword(s):

Repeated Measures ◽

Aloe Vera ◽

In Vitro Study ◽

P Value ◽

Fluoride Toothpaste ◽

Before And After ◽

The Difference ◽

Group B ◽

Ca:P Ratio

Abstract Objectives The aim of the present in vitro study is to compare the remineralization brushing effect of three toothpastes and Aloe vera (AV) gel. Materials and Methods Forty sound extracted teeth were placed in a demineralizing solution for 4 days and randomly assigned to four groups: group A: 1,450-ppm fluoride toothpaste; group B: AV nonfluoridated toothpaste; group C: AV 1,000-ppm fluoridated toothpaste; and group D: AV gel. A 3-minute pH cycling was performed twice a day for each group for 12 days. Specimens were analyzed before and after by scanning electron microscope—energy dispersive X-ray. Statistical analysis The outcomes were analyzed by Kolmogorov–Smirnov’s tests, repeated-measures analyses of variance followed by univariate analyses, and Bonferroni’s multiple comparisons tests to compare the calcium-to-phosphorus (Ca:P) ratio within time among toothpaste groups. Results Following remineralization, the Ca:P ratio increased in all groups. The difference of the Ca:P ratio was not significant between groups C, D, and A. The mean ratio was significantly lower in group B (p-value = 0.026). Conclusions The AV gel demonstrated a remineralization capacity equal to that of the 1,450-ppm fluoride toothpaste. In contrast, fluoride-free AV toothpaste showed a lower remineralization efficiency. Further studies are required to understand its mechanism.

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The IG- file use to Gauge the Apical Diameter in Endodontics: An In Vitro Study

The Open Dentistry Journal ◽

10.2174/1745017901814010638 ◽

2018 ◽

Vol 12 (1) ◽

pp. 638-646 ◽

Cited By ~ 1

Author(s):

Massimo Amato ◽

Alfredo Iandolo ◽

Giuseppe Pantaleo ◽

Dina Abtellatif ◽

Michele Simeone ◽

...

Keyword(s):

Measurement Accuracy ◽

Reference Value ◽

In Vitro Study ◽

Vitro Study ◽

Root Canals ◽

New Instrument ◽

Clinician Experience ◽

Incorrect Measurement ◽

The Difference

Aim: The aim of this study was to evaluate the efficacy of the IG-file, a new instrument designed for apical diameter gauging. Materials and Methods: After shaping with F1 Universal Protaper, 60 roots were randomly divided into two groups and assigned to two operators, One Expert in Endodontics (EO) and One Unexpert (UO). In each sample, after canal curvatures have been detected, the apical diameters were measured with the IG-file and the K-NiTi. The results were compared with the reference value obtained by retrograde apical gauging. The data were statistically analyzed. Results: Among 60 samples, 10% of errors were recorded when the IG-files were used; in the K-NiTi group the incorrect measurements were 70%. In both groups (expert and unexpert) the IG-file measurements were more accurate than the K-NiTi (90 vs 33 and 90 vs 26,7). The differences were statistically significant. In curved canals, the difference between measurement rates performed with both instruments was statistically significant (85,7% IG-file vs 28,6% K-NiTi) as well as for the samples without curvatures (92,3% IG file vs 30,8% NiTi file). In root canals without curvatures overestimation errors in K-NiTi file group are more frequent than underestimation errors. This difference was statistically significant. Conclusion: A proper gauging of the apical diameter has a key role in endodontic therapy; an incorrect measurement can lead to clinical failures. This “in vitro” study highlights that IG-file improves measurement accuracy independently from clinician experience. Furthermore, in curved canals, the IG-file is more accurate than K-NiTi.

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Impact of Bleaching before or after Veneer Preparation on Color Masking Ability of Laminate Veneers: An In Vitro Study

BioMed Research International ◽

10.1155/2021/6611173 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Gollshang Ahmad Mhammed Dalloo ◽

Bestoon Mohammed Faraj ◽

Abdulsalam Rasheed Al-Zahawi

Keyword(s):

Hydrogen Peroxide ◽

Color Change ◽

In Vitro Study ◽

Tooth Discoloration ◽

Significant Difference ◽

Color System ◽

The Difference ◽

Laminate Veneers ◽

Cielab Color

Purpose. This study evaluates the effect of bleaching before or after veneer preparation and the depth of preparation on color masking ability of laminate veneers. Methods. Sixty extracted premolars were artificially stained to vita shade A4, verified by digital spectrophotometer (Vita Easy Shade V), and then divided into three groups: NB = nonbleached , BBP = bleaching before preparation, and BAP = bleaching after preparation. Based on the preparation depths, each group was further divided into two subgroups: S 1 = 0.5 mm and S 2 = 1.0 mm . BBP and BAP were subjected to one session of in-office bleaching using 35% hydrogen peroxide. IPS e-max CAD veneers of 0.5 and 1.0 mm thickness (corresponding to the preparation depths) of the same shade and translucency (HT A1) were cemented immediately to the bleached surfaces. Immediately after cementation, the color change Δ E between the baseline (after staining) and the resulted shades was measured using the Vita Easy Shade V digital spectrophotometer and CIELab color system. Results. Bleached groups exhibited a significant Δ E value compared to the nonbleached group ( p < 0.05 ). BAP showed the highest Δ E value. No significant difference was found between BBP and BAP. S2 revealed a significant Δ E value than S1 ( p < 0.05 ). No significant difference was found between S1of BAP and S2 of NB, BBP, and BAP ( p > 0.05 ). Regarding the color coordinates, the difference between the tested groups was highly significant in lightness ( Δ L ∗ ) ( p < 0.001 ), while no significant differences were found in green/red value ( Δ a ∗ ) and yellow/blue value ( Δ b ∗ ) ( p > 0.05 ). Conclusions. In cases of severe tooth discoloration, one session of in-office bleaching before or after veneer preparation and the preparation depth do not influence the color masking ability of laminate veneers.

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Arabidopsis ALIX is required for the endosomal localization of the deubiquitinating enzyme AMSH3

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1510516112 ◽

2015 ◽

Vol 112 (40) ◽

pp. E5543-E5551 ◽

Cited By ~ 32

Author(s):

Kamila Kalinowska ◽

Marie-Kristin Nagel ◽

Kaija Goodman ◽

Laura Cuyas ◽

Franziska Anzenberger ◽

...

Keyword(s):

Cellular Level ◽

Deubiquitinating Enzymes ◽

Interacting Protein ◽

Endosomal Sorting ◽

Cellular Processes ◽

Late Endosomes ◽

Knockout Mutants ◽

Important Regulator

Ubiquitination is a signal for various cellular processes, including for endocytic degradation of plasma membrane cargos. Ubiquitinating as well as deubiquitinating enzymes (DUBs) can regulate these processes by modifying the ubiquitination status of target protein. Although accumulating evidence points to the important regulatory role of DUBs, the molecular basis of their regulation is still not well understood. Associated molecule with the SH3 domain of signal transduction adaptor molecule (STAM) (AMSH) is a conserved metalloprotease DUB in eukaryotes. AMSH proteins interact with components of the endosomal sorting complex required for transport (ESCRT) and are implicated in intracellular trafficking. To investigate how the function of AMSH is regulated at the cellular level, we carried out an interaction screen for the Arabidopsis AMSH proteins and identified the Arabidopsis homolog of apoptosis-linked gene-2 interacting protein X (ALIX) as a protein interacting with AMSH3 in vitro and in vivo. Analysis of alix knockout mutants in Arabidopsis showed that ALIX is essential for plant growth and development and that ALIX is important for the biogenesis of the vacuole and multivesicular bodies (MVBs). Cell biological analysis revealed that ALIX and AMSH3 colocalize on late endosomes. Although ALIX did not stimulate AMSH3 activity in vitro, in the absence of ALIX, AMSH3 localization on endosomes was abolished. Taken together, our data indicate that ALIX could function as an important regulator for AMSH3 function at the late endosomes.

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Different iron-handling in inflamed small and large cholangiocytes and in small and large-duct type intrahepatic cholangiocarcinoma

European Journal of Histochemistry ◽

10.4081/ejh.2020.3156 ◽

2020 ◽

Vol 64 (4) ◽

Author(s):

Romina Mancinelli ◽

Antimo Cutone ◽

Luigi Rosa ◽

Maria Stefania Lepanto ◽

Paolo Onori ◽

...

Keyword(s):

Iron Homeostasis ◽

Tumor Development ◽

In Vitro Models ◽

Molecular Forms ◽

Cellular Processes ◽

Small Duct ◽

Transferrin Receptor 1 ◽

The Difference ◽

Tumor Management

Cholangiocarcinoma (CCA) represents the second most common primary hepatic malignancy and originates from the neoplastic transformation of the biliary cells. The intrahepatic subtype includes two morpho-molecular forms: large-duct type intrahepatic CCA (iCCA) and small-duct type iCCA. Iron is fundamental for the cellular processes, contributing in tumor development and progression. The aim of this study was to evaluate iron uptake, storage, and efflux proteins in both lipopolysaccharide-inflamed small and large cholangiocytes as well as in different iCCA subtypes. Our results show that, despite an increase in interleukin-6 production by both small and large cholangiocytes, ferroportin (Fpn) was decreased only in small cholangiocytes, whereas transferrin receptor-1 (TfR1) and ferritin (Ftn) did not show any change. Differently from in vitro models, Fpn expression was increased in malignant cholangiocytes of small-duct type iCCA in comparison to large-duct type iCCA and peritumoral tissues. TfR1, Ftn and hepcidin were enhanced, even if at different extent, in both malignant cholangiocytes in comparison to the surrounding samples. Lactoferrin was higher in large-duct type iCCA in respect to small-duct type iCCA and peritumoral tissues. These findings show a different iron handling by inflamed small and large cholangiocytes, and small and large-duct type iCCA. The difference in iron homeostasis by the iCCA subtypes may have implications for the tumor management.

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