Scanning Electron Microscopy Evaluation Research Articles

Characterization of Tilapia collagen-loaded chitosan nanofibers synthesized by electrospinning method for wound dressing

Burns are traumatic injuries that require intensive therapy. Tilapia skin is known to contain high collagen properties and was developed for wound dressing. This study aimed to investigate the characterization of Tilapia collagen-loaded chitosan nanofibers synthesized by electrospinning for wound dressing. This study evaluated three group materials, i.e. (G1) chitosan, (G2) Tilapia collagen, and (G3) Tilapia collagen-loaded chitosan. The electrospun method was performed by alloy the chitosan nanofibers containing 8% w/v Tilapia collagen. The mix solution was characterized using scanning electron microscopy (SEM), Fourier- transform infrared (FTIR) spectroscopy, pH level, swelling test, water capacity test, and cytotoxicity test. As result, Tilapia collagen-loaded chitosan showed the better swelling test, water capacity test, cytotoxicity test, and FTIR evaluation compared to the collagen or chitosan group. However, all group materials showed similarities in pH level and SEM evaluation. In conclusion, Tilapia collagen-loaded chitosan nanofibers could be considered as a wound dressing based on positive results during characterization.

Evaluation of Coronal Micro-Leakage of Fiber Post with Different Luting Cements (In Vitro Study)

Evaluation of Coronal Micro-Leakage of Fiber Post with Different Luting Cements (In Vitro Study)

Cyclic Fatigue Resistance and SEM Evaluation of Fractured Instrument Surfaces; Comparison of ProTaper Universal and ProTaper Gold Files

Purpose:To compare the cyclic fatigue resistance of ProTaper Universal (PTU) and ProTaper Gold (PTG) nickel titanium files at different angles and to examine the fractured surface areas by using scanning electron microscope (SEM). Materials and Methods: A special static test device made of stainless steel with artificial canals at 3 different angles. The files were rotated until they were broken in artificial canals with 45°, 60° and 90° angles and also the time was recorded using a digital stopwatch. The number of cycles to failure was calculated for each instrument. Statistical analyzes were made by using one-way analysis of variance (Anova) for comparison between main groups. Results: PTG files showed higher fatigue resistance (p

Comparative Study of the SEM Evaluation, EDX Assessment, Morphometric Analysis, and Cyclic Fatigue Resistance of Three Novel Brands of NiTi Alloy Endodontic Files.

In this study, we compare and analyze the scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), morphometry and cyclic fatigue resistance of Endogal, PathMax, and Smarttrack novel brands of nickel–titanium (NiTi) alloy endodontic files. Material and Methods: Thirty sterile NiTi endodontic rotary files were randomly selected and assigned to one of the following study groups: A: 25.08 F2 Endogal (EDG) (n = 10); B: 25.08 F2 Path Max Pro (PMP) (n = 10); and C: 25.06 Smarttrack (ST) (n = 10). Dynamic cyclic fatigue tests were conducted using a cyclic fatigue device in stainless steel artificial root canal systems with an apical diameter of 250 µm, curvature angle of 60°, radius of curvature of 3 mm, and taper of 6%. Additionally, we analyzed the NiTi endodontic rotary files using EDX, SEM, and morphometry after micro-CT scanning. The results were analyzed using Weibull statistical analysis and ANOVA testing. Results: SEM, EDX, and morphometric analyses showed differences between the three novel brands of NiTi endodontic rotary files. Moreover, statistically significant differences were observed between the number of cycles to failure and time to failure of the three novel brands of NiTi endodontic rotary files (p < 0.001). Conclusions: Smarttrack NiTi alloy endodontic reciprocating files display greater resistance to cyclic fatigue than Endogal and Path Max Pro NiTi alloy endodontic rotary files, due to the reciprocating movement and metallurgical composition.

Tridimensional roughness and morphology of sound dentin surfaces after papain-gel treatment

Purpose: To investigate the effect of chemomechanical caries removing agents (CCRAs) based on papain (Papacárie Duo Gel® and Brix3000®) over dentin surfaces compared with 37% phosphoric acid and 11.5% polyacrylic acid.Materials and methods: Sound human molars were sectioned at the crown level, resulting in 48 dentin blocks, which were randomly divided into 4 groups (n=12): 1) Papacárie Duo Gel®; 2) Brix3000®; 3) 11.5% polyacrylic acid solution and 4) 37% phosphoric acid gel. All products were applied for 30s. Ten blocks per group were analyzed by a non-contact 3D profilometer before and after treatments for linear (Ra) and volumetric roughness (Sa). The superficial morphology of the remaining blocks in each group (n=2) was evaluated by scanning electron microscopy (SEM). Normality was rejected for the data (Shapiro-Wilk test) and therefore, Kruskal-Wallis test, followed by Dunn’s proof or Wilcoxon signed rank test with its respective effect size calculation were used to compare the results with α=5%.Results: Ra and Sa values for specimens submitted to Papacárie Duo Gel® and Brix3000® were statistically similar to baseline values. Application of phosphoric and polyacrylic acid resulted in a statistically increase in roughness compared to the CCRAs. SEM evaluation showed that Papacárie Duo Gel® resulted in surface debris. Polyacrylic acid and Brix3000®resulted in partial opening of the tubules but dentin exposed to polyacrylic was able to remove more smear layer than Brix3000®, while phosphoric acid resulted in total opening of the dentinal tubules.Conclusion: Both Papacárie Duo Gel® and Brix3000® did not result in roughness changes when applied in sound dentin.

Application of Artificial Neural Network in the Baking Process of Salmon

The global production of farmed Atlantic salmon amounts to over 2 million tons per year. Consumed all over the world, salmon is not only delicious but also nutritious. This paper deals with the relationship between moisture content, low-field nuclear magnetic resonance (LF-NMR), scanning electron microscope (SEM), and sensory evaluation in the baking process of salmon. An artificial neural network (ANN) model has been established to simulate the change of moisture content and energy consumed in the baking process. Through the study of LF-NMR, SEM, and sensory evaluation, it was found that the change of sensory indexes was consistent with the results observed by LF-NMR and SEM. With the increase of temperature, muscle fibers contracted, the interstices increased, the rate of water loss increased, and the sensory score decreased. Initial moisture content, baking time, baking temperature, baking humidity, and baking air velocity were employed as the baking control parameters for the ANN. ANN can be used to determine the moisture content and energy consumed of baking salmon. The best network topology occurred with 5 input layer neurons, 17 hidden layer neurons, and 2 output layer neurons, and the MSE was 0.00153, and Rall was 0.99661. According to the experiment, it was demonstrated that the ANN is a reliable software-based method.

A Scanning Electron Microscope Evaluation of the Efficacy of Different Fluoride-releasing Dental Restorative Materials to Prevent Enamel Demineralization: An In Vitro Study

Aim of the present research was to investigate the effectiveness of various fluoride-releasing dental restorative agents in preventing demineralization of enamel. Eighty human mandibular permanent molar teeth constituted the study group. All samples were subjected to storage in thymol, after which they were taken out to prepare alike proximal box in each. Inductions of artificial enamel surface lesions were done by placing the teeth in demineralizing solution for 96 hours. Subsequently, all 80 molars were randomly assigned to any of the four groups (i.e., 20 in every individual group) according to the restoration as group A: giomer (composite resin containing surface pre-reacted glass-ionomer fillers), group B: compomer (polyacid-modified composite resin), group C: resin-modified glass-ionomer cement (RMGIC), group D: fluoride-releasing composite. After this, the pH cycling was performed, and the samples were subjected to examination beneath scanning electron microscope (SEM). Higher mean areas of remineralization were noted when RMGIC (96.34 ± 0.06) was used followed by the compomer (109.52 ± 0.17), giomer (118.39 ± 0.82), and the fluoride-releasing composite group (129.27 ± 0.31) in that order. A statistically significant difference was seen amid the investigational groups that utilized different restorative agents (p <0.001). A pairwise evaluation that was performed revealed that except for the giomer group and the compomer group, a statistically significant difference (p <0.001) was found among the experimental groups. This research infers that the RMGIC-treated samples exhibited significantly superior performance in preventing enamel demineralization in comparison to compomer, giomer as well as fluoride-releasing composites. One among the highly frequently employed anticariogenic materials is fluorides. Owing to this characteristic, they are integrated into numerous restorative substances. Nevertheless, the quantity and speed of fluoride release differ in different agents, which translates to the efficacy of the restorative agent in avoiding demineralization about the restoration.

The Impact on Dental Staining Caused by Beverages in Combination with Chlorhexidine Digluconate.

There are several hypotheses regarding how chlorhexidine (CHX) digluconate causes staining with the role of beverages, specifically the precipitation of anionic dietary chromogens onto adsorbed cations, the most probable cause. The aim of this study was to investigate and compare the staining potential of common beverages using an in vitro staining and brushing model to better understand the interactions between chromogens from different beverage categories and the teeth. Human enamel samples were exposed to a cyclic treatment of artificial saliva and 0.2% CHX mouthwash combined with a range of beverages, with and without brushing, simulating a period equivalent to 2 weeks. Eleven beverages were tested: diet coke, diet lemonade, white wine, red wine, lager beer, black tea, coffee, black tea with milk, coffee with milk, ginger and lemon infusion, and water. Toothbrushing was performed in a brushing simulator with toothpaste and also with water. Colorimetric differences were determined by ΔE using a VITA Easyshade dental spectrophotometer. Statistical analyses were performed by one-way analysis of variance with post hoc Tukey's honestly significant difference test and Levene's test. Black tea and red wine produced highest staining, which agrees with the literature. Significant staining was also observed for a ginger and lemon infusion, coffee, coffee with milk, tea with milk, and lager beer compared with water (p < 0.05). The staining potential of diet coke in combination with brushing appeared to be connected to its low pH. Both white wine and diet lemonade produced stain comparable to the water control. After treatment with high staining beverages, scanning electron microscope evaluation confirmed the formation of a surface layer. The mechanical resistance of the stain differed depending on the beverage, black tea stain was the most resistant. The addition of milk to tea and coffee considerably modified the stain layer and the adhesion to the tooth surface. The data may help demonstrate that appropriate user guidance can avoid stain and in turn help improve user compliance during short-term use of this gold standard antimicrobial treatment.

EFFICACY, TOOTH SURFACE MICROHARDNESS AND ROUGHNESS AFTER TREATMENT WITH COMBINATION OF LASER AND HOME BLEACHING PROTOCOL: AN IN VITRO STUDY

Teeth whitening or bleaching has pleased people with aesthetic concerns for long. To improve the efficacy of bleaching and reduce the ill effects on the tooth surface, a combination of power bleaching (PB) and home bleaching (HB) can be used. Objective. To compare the efficacy and effects of combinations of PB/laser bleaching (LB) and HB protocol on human natural tooth structure. Materials &amp;amp; methods: Eighty-eight permanent maxillary central incisors were randomly divided into four groups (n=22). After staining, teeth were bleached using different bleaching protocols: Group 0 (control), Group 1 (Laser White 20 46% hydrogen peroxide (HP) + Opalescence PF 20% carbamide peroxide (CP) – HB sequence for 3 days), Group 2 (Laser White 20 46% HP + Opalescence PF 20% CP – HB sequence for 7 days), Group 3 (Opalescence PF 20% CP – HB sequence for 14 days). Colorimetric measurement was performed, enamel surface roughness and microhardness were measured. Scanning Electron microscope (SEM) evaluation was done to compare the surface topography. Pre and post bleaching data were analysed using paired T-test. Multiple comparison between groups was carried out using one-way ANOVA complemented by Post hoc test (Bonferroni), with significance level set at P&amp;lt;0.05. Results: All protocols demonstrated significant efficacy to whiten stained enamel. All groups demonstrated significant increase in hardness (P&amp;lt;0.05). Surface roughness reduced significantly in Group 1 and 2. SEM showed that Group 1 had a similar microscopic surface appearance as unbleached enamel, while Group 3 had accentuated irregularities. Conclusion: LB followed by HB for 3 days is the most effective in whitening stained teeth with positive effects on tooth surface hardness while maintaining surface topography of dental hard tissues.

Machine-Assisted Irrigation Systems for Smear Layer Removal in Root Canal Treatment

Objectives: The objective was to evaluate the efficacy of three machine-assisted irrigation systems in smear layer removal from apical one-third of the root canal system. Data Source: A comprehensive search of last 10 years was performed in the following systematic electronic database: PubMed/Medline and Scopus. Data Selection: We included in-vitro studies that compared Endoactivator, Endovac, and Passive ultrasonic irrigation system's clinical success of smear layer removal in apical one-third of the root canal systems. Data Synthesis: A total of 72 nonduplicated studies were retrieved in the systematic search. Seven studies included in the study assessed the success rate of smear layer removal in the apical third of the root canal system of three irrigation systems through scanning electron microscopic evaluation. These studies were classified as low risk of bias. The studies evaluating the scanning electronic microscopy of smear layer removal in the apical one-third of the root canal comparing the Endoactivator and Passive ultrasonic irrigation showed no statistical difference (P &lt; 0.05). The studies evaluating the scanning electronic microscopy of smear layer removal in the apical one-third of the root canal comparing the Endoactivator and Endovac showed statistical difference (P &gt; 0.05). Conclusion: Based on the findings, Endovac irrigation system was found to be effective in smear layer removal from apical one-third of the root canal system. Further in-vivo studies and clinical trials are required for more conclusive results.

Evaluation and comparison of mechanical properties of platelet-rich fibrin membrane, fish collagen membrane, bovine collagen membrane and chorionic membrane - An SEM study.

This study aimed to evaluate and compare the mechanical properties of platelet-rich fibrin (PRF) membrane with that of commercially available collagen membranes and chorionic membranes. The modulus of elasticity and hardness of PRF membrane, bovine collagen membrane, fish collagen membrane, and chorionic membrane were assessed using a universal testing machine. The in vitro degradation rate was assessed by placing these membranes on a temperature-controlled shaker set for one week. The degradation profiles were expressed as the accumulated weight loss of the membrane. A scanning electron microscope (SEM) evaluation of these membranes was done under both low and high magnification. One-way analysis of variance (ANOVA) and Tukey's post hoc tests were performed for statistical analysis. A statistically significant difference in the tensile strength and hardness of membranes was observed. Bovine collagen membrane had the highest strength (84.11 MPa and 16.46 MPa) followed by fish collagen membrane, chorionic membrane, and least for PRF membranes observed. The degradation rate at one week was highest for the PRF membrane (55.6%), followed by the fish collagen membrane (32.5%). SEM evaluation showed that the bovine collagen membrane had significantly higher numbers of collagen fibres compared to the fish collagen membrane and chorionic membrane. Bovine collagen membrane had the highest mechanical properties with the maximum amount of collagen fibre meshwork. Only the PRF membrane had cellular distribution in its composition, while the commercially available membrane had significantly higher numbers of collagen fibres with the total absence of cellular components.

Scanning electron microscopic evaluation of the effect of different root-end resection methods in the crack formation in root canals filled with mineral trioxide aggregate or calcium-enriched mixture cement

There is some concern that root resection may alter the surface features and crack formation of the previously set orthograde material. The aim of this in vitro study was to evaluate the crack formation in orthograde mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) plugs after root resection.This in vitro study was conducted on 170 extracted human maxillary anterior teeth. The teeth were randomly divided three experimental (n = 50) and control (n = 20) groups. In Group 1, after root canal treatment, half of the roots were cut with a bur, and the other half with an ultrasonic cutter. In Groups 2 and 3, after the 4-mm CEM and MTA plugs were placed and set, the root ends of half of the samples were cut with a bur and the other half by an ultrasonic cutter. The prevalence of cracks in the dentin and orthograde apical plugs of MTA and CEM was then assessed by scanning electron microscopy. Data were analyzed using the McNemar's, Chi-square, and Fisher's exact tests at P ≤ 0.05 level of significance.In general, the prevalence of crack in dentin in Groups 2 and 3 was significantly higher than in the plug (P < 0.05). There was no significant difference in the prevalence of dentin crack in the studied groups (P > 0.05). The prevalence of crack in dentin was lower when the bur was used to cut off the end of the root, although the difference was not significant. The prevalence of crack in the plug was similar in CEM and MTA.Based on the results of this study, the prevalence of crack in dentin is always significantly higher than its prevalence in the plug, and the prevalence of crack in the plug was similar in CEM and MTA; then, when there is an orthograde access to the root canal and surgery is likely in future, MTA and CEM can be placed in an orthograde technique and it just resects the root during surgery.

Comparison of cyclic fatigue resistance of different and novel heat-treated nickel-titanium rotary file systems at the intracanal temperature

Aim: The aim of this study was to compare the cyclic fatigue resistance of different heat-treated nickel-titanium rotary systems at intracanal temperature. &#x0D; Methodology: A total of 90 OneCurve (Micro-Mega, Besançon, France), VDW.ROTATE (VDW Dental, Munich, Germany), Typhoon (Clinician’s Choice, New Milford, CT, USA), HyFlex EDM (Coltene/Whaledent AG, Altstatten, Switzerland), and EndoArt Gold and Blue (Inci Dental, Istanbul, Turkey) (n = 15) rotary files (#25/0.06) were tested at intracanal temperature (35.5 ℃) using a dynamic model in a stainless-steel artificial canal with an inner diameter of 1.5 mm, 60° angle of curvature, and 2 mm radius of curvature. Testing was conducted until fracturing, at which time the device stopped automatically, and the number of rotations was calculated as seconds. Lengths of fractured parts were measured using a digital caliper. One-way ANOVA test followed by Tukey’s test was used to compare the groups. Scanning electron microscopic evaluation was performed to confirm the types of fracture.&#x0D; Results: EndoArt Blue group had a significantly higher mean time to fracture in all groups, followed by the HyFlex EDM, VDW.ROTATE, OneCurve, EndoArt Gold, and Typhoon. In addition, the HyFlex EDM and VDW.ROTATE groups had no significant differences between each other and were significantly better than the others. No significant differences were found between the OneCurve, EndoArt Gold, and Typhoon groups (p&gt;0.05).&#x0D; Conclusion: This is the first study in the literature for EndoArt NiTi files and the second study for VDW.ROTATE that evaluated cyclic fatigue resistance. Novel EndoArt Blue files exhibited significantly greater cyclic fatigue resistance than the other NiTi files.&#x0D; &#x0D; How to cite this article: Güneç HG, Keskin NB, Haznedaroğlu F. Comparison of cyclic fatigue resistance of different and novel heat-treated nickel-titanium rotary file systems at intracanal temperature. Int Dent Res 2021;11(3):158-64. https://doi.org/10.5577/intdentres.2021.vol11.no3.4&#x0D; &#x0D; Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Comparison of Bond Strength in the Different Class of Resin Cements to Cast and CAD/CAM Co-Cr Alloys.

Objectives Despite the widespread use of resin cements in cementing dental restorations, their bond strength to CAD/CAM base metal alloys is not widely studied. This study aimed to evaluate the microshear bond strength (μSBS) between cobalt-chrome (Co-Cr) alloys fabricated using casting or CAD/CAM methods with three types of resin cements. Materials and Methods Fifty Co-Cr blocks were prepared with CAD/CAM or casting technique. Specimens were divided using primer or not and bonded to three types of resin cements: Panavia F2, RelyX Unicem, and Duo-Link. The differences between the mean μSBS values were analyzed using the two-way ANOVA test and Tukey analysis (α = 0.05). The mode of failure was evaluated using a stereomicroscope. In addition, the specimens were examined by scanning electron microscopy (SEM) based on two received signals: backscattered electrons (SEB) and secondary electrons (SEs). One intact alloy specimen in each group was analyzed by energy-dispersive X-ray spectroscopy (EDX). Results Most of the specimens in the no-primer group were prematurely debonded. Statistical analyses showed that the interaction between the alloy substrate and cement type was significant (p=0.001). The bond strength of Panavia F2 was significantly higher than Duo-Link in the CAD/CAM group (p=0.001). SEM evaluation confirmed the difference in grain structures, while EDX showed no remarkable difference in the chemical composition of the alloy substrates. Conclusion Alloy fabrication technique may influence the bond strength of resin cements. In the CAD/CAM group, cement containing MDP molecules exhibited higher strength than the etch-and-rinse one.

SEM Evaluation of Various Intracanal Irrigation Devices on Smear Layer Removal: A Comparative Study

The present study aimed at assessing the effectiveness of different intracanal irrigation devices on the removal of the smear layer. The recently extracted 80 lower premolars having single canal were chosen for this in vitro study. A round diamond bur was used to gain endodontic access and the root canal was entered with a #15 K-file until the tip was just seen at the apical foramen. Manual instrumentation of root canals of all teeth was done using the step-back method. The samples were later divided randomly into four groups. Later, each sample was exposed to final irrigation by using four different irrigation systems, group 1: conventional needle irrigation, group 2: irrigation with ultrasonic activation, group 3: irrigation with EndoVac system activation, group 4: irrigation with EndoActivator. The samples were next mounted and visualized under scanning electron microscope (SEM) for the absence or presence of the smear layer. Irrigation with EndoVac system activation showed the presence of least smear layer (2.40 ± 0.32), followed next by EndoActivator (3.24 ± 0.46) and ultrasonic activation (4.96 ± 0.54) and conventional needle irrigation (5.20 ± 0.10). No statistically significant difference was found in the apical and coronal thirds of the root canal in removal of the smear layer on an intragroup comparison. However, a statistically significant (p < 0.001) difference was seen between the groups at the apical and coronal thirds on an intergroup comparison. This study demonstrated the EndoVac system group to be efficient in removal of the smear layer when compared to the EndoActivator system, ultrasonic activation, and conventional needle irrigation group. The definitive objective of endodontic therapy is to transform the affected teeth to a healthy and functional state. The irrigants can reach the working length when delivered by an effective irrigation delivery system. This type of delivery system should deliver adequate volume of irrigants all the way up to the working length and have sufficient flow and be efficient at debridement of complete canal system.

Effect of Chemical Challenges on the Properties of Composite Resins.

Objective To evaluate the chemical degradation effect on microhardness and roughness of composite resins after aging. Materials and Methods Specimens (n = 10) were used for Filtek Z350 XT (Z350), Filtek Bulk Fill (BULK), Micerium HRI (HRI), Micerium BIOFUNCION (BIO), and Vittra APS (VITTRA). Microhardness and roughness were performed before and after degradation with the followed solutions: citric acid, phosphoric acid, 75% alcohol, and distilled water. Samples were to a 180-day chemical cycling protocol. After degradation, one sample of each group was selected for scanning electron microscope evaluation. The data were analyzed with normal distribution (Kolmogorov–Smirnov) and similarities of variations for the Bartlett test. ANOVA (two-way) followed by Tukey's test was performed considering treatment and composite resin (P < 0.05). Results For microhardness and roughness, variations were noted to different solution and resin formulations. Z350 and HRI showed higher microhardness percentage loss, and it was more evident after storage in alcohol (−48.49 ± 20.16 and −25.02 ± 14.04, respectively) and citric acid (−65.05 ± 28.97 and 16.12 ± 8.35, respectively). For roughness, Z350 and VITTRA showed less delta values after alcohol storage (−0.047 ± 0.007 and −0.022 ± 0.009, respectively). HRI had the worst roughness for citric acid (−0.090 ± 0.025). All resins were not statistically different between each other in water and phosphoric acid. Conclusion The formulations of restorative resin materials influenced in degree of surface degradation after 180 days of chemical degradation. Water was considered the solution that causes less degradation for microhardness and roughness evaluations. For microhardness, alcohol was considered the worst solution for Z350 and HRI. For superficial roughness, Z350 and VITTRA showed less degradation in alcohol and citric and phosphoric acid solutions.

Mn-doping-induced tunable bandgap and luminescence properties of SnO2 nanoparticles grown by SILAR method

In the present study, pure and Mn doped SnO2 thin films were grown by performing successive ionic layer adsorption and reaction (SILAR) method on the glass substrates at room temperature. The fabricated thin films have been studied to assess the influence of Mn doping on structural, morphological, and optical properties of SnO2 crystal lattice. The X-ray diffraction (XRD), Ultraviolet–visible spectrometer (UV–Vis), Energy dispersive X-ray analysis (EDAX), Scanning electron microscope (SEM), Raman, X-ray photoelectron spectroscopy (XPS), and Photoluminescence (PL) spectra measurements were conducted. After the XRD and SEM evaluations, it was found that the grown nanoparticles were in rutile type tetragonal structure of polycrystalline nature which was supported by Raman results. And, the surface morphologies were also observed to be affected from the varied concentrations of Mn doping. Besides, the EDAX evaluation confirmed the integration of Mn content next to Sn and O ions in the synthesized SnO2 nanostructures by SILAR method. The UVi-vis analysis disclosed that the absorbance of the prepared thin films had a clear inclination to increase as doping concentration intensified. In addition to that, the optical investigations also uncovered the bandgap of SnO2 nanocrystallines could be tuned from 2.61 eV to 2.00 eV by exposing them to the different levels of Mn ions. Furthermore, the Photoluminescence spectra evidently acknowledged the possibility of engineering optical characteristics by showing increased luminescent emission intensity values right after the introduction of impurities into the SnO2 lattice. The XPS results further verified the manganese and tin valences existed in the produced thin films.

Feline sarcomatoid renal cell carcinoma with peritoneal carcinomatosis and effusion.

A 9-y-old, castrated male, domestic medium-hair cat diagnosed previously with chronic kidney disease developed anorexia and vomiting. Ultrasonography revealed abdominal effusion and a left renal perihilar mass. Cytologic evaluation of the peritoneal fluid and mass identified atypical epithelioid cells suspected to be of renal epithelial or possible mesothelial origin. Immunohistochemical (IHC) evaluation of a formalin-fixed, paraffin-embedded peritoneal fluid cell block indicated both pancytokeratin and vimentin expression in the atypical epithelioid cell population. With scanning electron microscopic evaluation, similar epithelioid cells lacked the cell-surface microvilli expected of mesothelium, supporting an antemortem diagnosis of probable carcinoma. On postmortem examination, the left kidney was effaced by an infiltrative neoplasm with myriad similar nodules throughout the peritoneum. The neoplasm was composed primarily of polygonal-to-spindle-shaped cells with strong vimentin and weak pancytokeratin cytoplasmic immunolabeling. Further IHC characterization with PAX8, CK18, KIT, napsin A, SMA, desmin, CD18, and claudin 5 was performed. Histologic and IHC findings supported a diagnosis of sarcomatoid renal cell carcinoma with peritoneal carcinomatosis. An in vitro cell culture line of neoplastic cells harvested from the primary tumor was successfully established for future research endeavors.

Use of alginate hydrogel to improve long-term 3D culture of spermatogonial stem cells: stemness gene expression and structural features.

The quality and quantity of a spermatogonial stem-cell (SSC) culture can be measured in less time using a 3D culture in a scaffold. The present study investigated stemness gene expression and the morphological and structural characterization of SSCs encapsulated in alginate. SSCs were harvested from BALB/c neonatal mice testes through two-step mechanical and enzymatic digestion. The spermatogonial populations were separated using magnetic-activated cell sorting (MACS) using an anti-Thy1 antibody and c-Kit. The SSCs then were encapsulated in alginate hydrogel. After 2 months of SSC culturing, the alginate microbeads were extracted and stained to evaluate their histological properties. Real-time polymerase chain reaction (PCR) was performed to determine the stemness gene expression. Scanning electron microscopy (SEM) was performed to evaluate the SSC morphology, density and scaffold structure. The results showed that encapsulated SSCs had decreased expression of Oct4, Sox2 and Nanos2 genes, but the expression of Nanog, Bcl6b and Plzf genes was not significantly altered. Histological examination showed that SSCs with pale nuclei and numerous nucleolus formed colonies. SEM evaluation revealed that the alginate scaffold structure preserved the SSC morphology and density for more than 60 days. Cultivation of SSCs on alginate hydrogel can affect Oct4, Sox2 and Nanos2 expression.

A Comparison of One Shape and ProTaper Next Rotary Systems for Elimination of Enterococcus Faecalis from Root Canal: Microbiological and SEM Evaluation

Incomplete removal of micro- organisms from infected root canals is a common cause of failed endodontic treatment. The difficulty in eradication of Enterococcus faecalis from root canals plays an essential role in pathogenesis of persistent pulpal and periradicular infections. The aim of the present study was to compare the reduction of Enterococcus faecalis in root canals by mechanical instrumentation using two rotary systems (One Shape and ProTaper Next) and Hand K-file instrumentation by using microbiological and Scanning Electron Microscopy (SEM) evaluation. Fifty one freshly extracted mandibular premolars with a single root were collected. After pre-instrumentation sampling, they were divided into three groups, Group A, Group B and Group C in which biomechanical preparation was done using Hand K-File, OneShape and Protaper Next respectively. Reduction in pre- instrumentation and post- instrumentation values of Enterococcus faecalis were analysed using microbiological and SEM evaluation. Statistical analysis by paired ‘t’ test and p value showed that there was highly statistical significant difference in CFU count reduction between the pre-instrumentation and post-instrumentation values in all the groups (p&lt;0.001). Statistical analysis by Kruskal-Wallis Test and Mann-Whitney Test showed that at 1mm and 3mm level, Group A (Hand K-File) scored significantly higher value followed by Group B (OneShape Apical) and Group C (ProTaper Next). The most effective instrumentation technique in eliminating Enterococcus faecalis from the root canal was ProTaper Next system in comparison to OneShape Apical and Hand K-File.