Effect of resin thickness, and curing time on the micro-hardness of bulk-fill resin composites

Background: Bulk-fill resin composite has been introduced, their manufacturers claimed that they can be applied in bulks of 4mm, without necessitating a prolonged curing time, or a light curing unit with increased irradiance. Thus this study was conducted to evaluate the effect of resin thickness, and curing time on the micro-hardness of two bulk -fill resin composites; Tetric Evo-Ceram [TE], and X-trafil [XF]. Material and Methods: 120 cylindrical specimens were prepared, and divided into 24 groups (n=5/group), representing the two bulk-fill resin composites, three different material thicknesses (2, 3 and 4 mm) and the four curing times used in the study (10, 20, 40, and 60 seconds). The specimens were light-cured from the top surface only. Specimens were stored in light proof containers in complete darkness at 37°C for 24 hours. Micro-hardness test was conducted on both top and bottom surfaces using Vickers micro-hardness tester with 500 g load and a dwell time of 15 seconds. Data were statistically analyzed by Four-way ANOVA of Variance. The significance level was set at P ≤ 0.05. Pearson Correlation used to determine significant correlations between mean micro-hardness (top) and (bottom) surfaces. Results: Four way-ANOVA shows that different tested materials produce a statistically significant effect on mean micro-hardness (VHN) at p ≤0.001, while thickness, curing time, and surface revealed statistically non significant effect on mean micro-hardness (VHN) at p ≥0.05. [XF] (92.01±3.15 VHN) showed statistically significant higher mean micro-hardness than [TE] (54.13±4.96 VHN). Pearson Correlation revealed that there was a significant direct correlation between micro-hardness (bottom) and mean micro-hardness (top) (mm), r = 0.985, p (2-tailed) ≤0.001. Conclusions: Within the limitations of this study, the bulk-fill resin composites used in this study can be placed and cured properly in the 4 mm bul

Evaluation of diode laser application on chemical analysis and surface microhardness of white spots enamel lesions with two remineralizing agents

To investigate the effect of diode laser application and two commercial remineralizing agents on the remineralization and surface microhardness of white spot enamel lesions. Sixty specimens were prepared then equally divided into six groups (n=10/group), according to the diode laser and the two commercial remineralizing agents applied to demineralized enamel surfaces (APF gel and sodium fluoride NaF mousse) with or without diode Laser application as follows; Group A; control, Group B; diode Laser application, Group C; APF gel application, Group D; NaF mousse application, Group E; APF gel application + diode Laser, Group F; NaF mousse application+ diode Laser. Then the teeth were investigated for their Ca, P & F ions content and surface microhardness. One-way ANOVA followed by Tukey?s (HSD) post hoc test were used for statistical analysis. Ca ion wt% showed no statistically significant difference between tested groups, with the highest mean value recorded with Group C. P ion wt%, showed a statistically significant difference between Groups A and C, and the highest mean value was recorded for Group A. The highest F ion wt% was recorded for Group C, while the lowest was recorded for both A and B groups. The highest significant microhardness mean values was recorded for Group E, while the lowest was recorded for Group A. Diode Laser treatment of the demineralized enamel surface had a positive influence on the chemistry and surface microhardness and it may represent a promising adjunct for enamel surface remineralization

Coronavirus Classification using Deep Convolutional Neural Network, Models. and Chest ,X-ray images

The COVID-2019 virus, which was discovered for the first time in December 2019 in the city of Wuhan, China, went on to become a pandemic after rapidly spreading around the globe. As there are currently no reliable automated toolkits on the market, there has been an increase in the demand for supplementary diagnostic tools for COVID19 patients. It may be possible to improve the accuracy of the diagnosis of covid19 disease by making use of more recent developments in artificial intelligence (AI) approaches and radiological imaging. In this research, three different convolution neural networks were applied to raw chest x-rays before the histogram filter was used for the basic pre-processing. The goal was to automatically detect COVID-19. The results that we obtained using the three suggested models indicate that the ResNet50 model provides the greatest classification performance with 96% accuracy , while the InceptionV3 model only achieves 95% accuracy, and the Inception-ResNetV2 model only achieves 82% accuracy

Diverse Glycosides from Gardenia latifolia with Antiviral Activity and Chemosystematic Significance

Several influenza pandemics have impacted our life, each with variable prevalence and severity. In a search for natural antivirals, further phytochemical investigation of Gardenia latifolia Aiton, Rubiaceae, was conducted. As a result, five structurally diverse glycosides were isolated, offering valuable chemotaxonomic data. Using the crystal violet technique, three isolates, canthoside C, (6R,7S,8S)-7α-[(β-d-glucopyranosyl) oxy] lyoniresinol, and ecdysanrosin A, were evaluated for their anti-influenza A (H1N1) activities. Based on previously reported anti-inflammatory activity of the guaiane class, we investigated the inhibitory effect of (1R,7R,8S,10R)-7,8,11-trihydroxy-guai-4-ene-3-one 8-O-β-d-glucopyranoside, a rare guaiane sesquiterpene glucoside, on inducible nitric oxide (NO) production by Griess assay. Regarding antiviral assay, canthoside C was the most active. It considerably inhibited H1N1 infectivity at an IC50 value of 10.93 µg/ml, showing a selectivity index (SI) of 12.88, compared with acyclovir as a standard. Besides, ecdysanrosin A displayed a moderate selective antiviral activity with an IC50 value of 28.03 µg/ml. Considering their low cytotoxicity on the host cells, canthoside C and ecdysanrosin A have additional merit as potential antiviral agents. Despite the claimed anti-inflammatory activity of guaianes, (1R,7R,8S,10R)-7,8,11-trihydroxy-guai-4-ene-3-one 8-O-β-d-glucopyranoside showed a limited anti-inflammatory activity. [Figure not available: see fulltext.

Promising selective MAO-B inhibition by sesamin, a lignan from Zanthoxylum flavum stems

© 2020 The Author(s) Monoamine oxidase inhibition is an important therapeutic approach for various neurodegenerative disorders. Reversible MAO inhibitors selectively targeting only one isoform possess substantial merit in terms of safety, efficacy, and side effect profile. This study aimed to isolate the secondary metabolites of Zanthoxylum flavum stems and evaluate their recombinant human MAO inhibition, antimicrobial, and antiprotozoal activities. As a result, fourteen compounds were isolated and identified (nine of them were reported from Z. flavum for the first time). Compound 3 (sesamin) exhibited potent selective MAO-B inhibition (IC50 value of 1.45 ± 0.05 µM) which reported herein for the first time. Compound 2 showed selective MAO-A inhibition activity, compound 5 exhibited good trypanocidal activity, and compound 7 displayed moderate antibacterial activity. The promising MAO-B inhibitory activity of sesamin provoked us to further explore the kinetic properties, the binding mode, and the underlying mechanism of MAO-B inhibition by this lignan. This detailed investigation substantiated a reversible binding and mixed MAO-B catalytic function inhibition via sesamin (Ki: 0.473 ± 0.076 μM). Selectivity and reversibility of sesamin on MAO-B provide exciting prerequisites for further in vivo investigation to confirm its therapeutic potentiality

A PRELIMINARY INVESTIGATION OF HTR1A GENE EXPRESSION LEVELS IN AUTISM SPECTRUM DISORDERS

Objective: This study was conducted to explore the expression levels of HTR1A gene in a sample of Egyptian autistic children. Methods: Thirty autistic patients (18 boys, 12 girls) and 20 controls were enrolled in the study. From each child, we isolated RNA samples from whole blood. Quantitative Real-Time PCR (qRT-PCR) was used to measure the gene expressions of HTR1A and normalized to the house keeping gene, beta-actin. Results: The HTR1A gene expression of healthy controls and ASD subjects were varied significantly (p =0.0062). As compared to control healthy subjects, the HTR1A expressions were greatly reduced in samples of ASD. Conclusion: HTR1A gene expression level is a candidate gene for further studies to explore its potential roles in ASD related pathways

Influence of immediate postpartum contraception counseling on the rate of unintended pregnancy in primigravida: a randomized controlled study

Background: The current study aims to assess the influence of immediate postpartum counselling about effective contraceptive methods to be used by primigravida on the rate of unintended pregnancy during first 6 months post-partum.Methods: The study was a prospective randomized controlled trial for assessment the influence of immediate postpartum counseling about effective contraceptive methods to be used by primigravida on the rate of unintended pregnancy during first 6 months post-partum who delivered at the period between the 1st of December 2016 and 31st of December 2017. The study patients were randomly assigned into two groups: Group (A) were received counseling about contraceptive methods using illustrations through postpartum interview with the study researcher. Group (B) were not received any counseling about contraceptive methods. The primary outcome was the difference in the rate of unintended pregnancy in both groups.Results: No significant difference between both groups in preventing unintended pregnancy. In group (A): After 3 months postpartum 140 women (93.3%) were used the contraceptive method correctly. 10 women used method incorrectly and 2 of them get pregnant. After 6 months postpartum 8 women did not use any method but 134 women (95.7%) were correctly used the contraceptive method. In group (B): After 3 months postpartum 127 women (84.7%) were used the contraceptive method correctly. 23 women used method incorrectly and 4 of them get pregnant. After 6 months postpartum 1 woman did not use any method but 30 women (20.7%) were incorrectly used the contraceptive method.Conclusions: Immediate post-partum counseling about contraceptive methods is good tool to educate women who intend to have optimal inter–pregnancy period about the effective methods that suit them and when to initiate

Pattern of cesarean deliveries among women in an urban and rural district in Egypt

Aim: to compare patterns of delivery at an urban and a rural district in Egypt over 3 years. Methods: This retrospective study included 500 women and 50 obstetricians from each district from January, 2013 till December, 2015. Women answered a questionnaire about their deliveries. Obstetricians answered a questionnaire about their practiceof CS. Results: CS rate in the rural district was 57.2% compared to 54.8% in the urban district in 2013. In 2014 and 2015, CS rates increased to 65.3% and 69%, respectively in the rural district compared to 56% and 57.7%, respectively in the urban district. 66% of obstetricians in the rural district performed CS for more than 50% of their patients compared to 76% of obstetricians in the urban district. 52% and 4% of obstetricians in the rural and urban districts, respectively, performed CS upon maternal request. 70.3% of women in the rural district who delivered by CS preferred to deliver vaginally. 51.4% of urban women who delivered by CS preferred to deliver vaginally. Level of education was the only factor showing statistical significance. Conclusion: CS rates increased over time with higher rates in the rural area. Level of women's education was the only factor affecting delivery choice. Keywords: Cesarean sections; CS rate; urban area; rural area; Egypt; obstetricians

In vitro cytotoxicity of Withania somnifera (L.) roots and fruits on oral squamous cell carcinoma cell lines: a study supported by flow cytometry, spectral, and computational investigations

Oral cancer is a severe health problem that accounts for an alarmingly high number of fatalities worldwide. Withania somnifera (L.) Dunal has been extensively studied against various tumor cell lines from different body organs, rarely from the oral cavity. We thus investigated the cytotoxicity of W. somnifera fruits (W-F) and roots (W-R) hydromethanolic extracts and their chromatographic fractions against oral squamous cell carcinoma (OSCC) cell lines [Ca9-22 (derived from gingiva), HSC-2, HSC-3, and HSC-4 (derived from tongue)] and three normal oral mesenchymal cells [human gingival fibroblast (HGF), human periodontal ligament fibroblast (HPLF), and human pulp cells (HPC)] in comparison to standard drugs. The root polar ethyl acetate (W-R EtOAc) and butanol (W-R BuOH) fractions exhibited the strongest cytotoxicity against the Ca9-22 cell line (CC50 = 51.8 and 40.1 μg/mL, respectively), which is relatively the same effect as 5-FU at CC50 = 69.4 μM and melphalan at CC50 = 36.3 μM on the same cancer cell line. Flow cytometric analysis revealed changes in morphology as well as in the cell cycle profile of the W-R EtOAc and W-R BuOH-treated oral cancer Ca9-22 cells compared to the untreated control. The W-R EtOAc (125 μg/mL) exerted morphological changes and induced subG1 accumulation, suggesting apoptotic cell death. A UHPLC MS/MS analysis of the extract enabled the identification of 26 compounds, mainly alkaloids, withanolides, withanosides, and flavonoids. Pharmacophore-based inverse virtual screening proposed that BRD3 and CDK2 are the cancer-relevant targets for the annotated withanolides D (18) and O (12), and the flavonoid kaempferol (11). Molecular modeling studies highlighted the BRD3 and CDK2 as the most probable oncogenic targets of anticancer activity of these molecules. These findings highlight W. somnifera’s potential as an affordable source of therapeutic agents for a range of oral malignancies

Allopurinol as a Potential Therapeutic Agent for Recurrent Herpes Labialis

Recurrent herpes labialis (RHL) occurs in up to 40% of the population. Although the disease is usually self-limiting, patients seek treatment because of the significant pain and visibility of the lesion. Xanthine oxidase inhibitors (XOI) have been reported to have a potent antiviral effect against influenza-A virus. We examined the effect of the systemic xanthine oxidase inhibitor, allopurinol, on RHL duration of illness, severity of symptoms, number and frequency of recurrence during a 4-year follow up period in Egyptian patients. Duration of illness was shortened by about 25%, early disappearance of pain and other symptoms occurred. Also, aborted episodes were noticed when allopurinol was given just after beginning of common colds, at the prodromal stage of RHL or during severe stress conditions. Patients receiving 3 courses of treatment had markedly decreased recurrences during the follow up period. Ex vivo experiments to examine virus-induced plaque formation on Vero cells in the absence or presence of different concentrations of the drug could not prove any direct anti herpetic effect of the drug. However, allopurinol seems to be safe and effective in reducing duration of RHL and to abort lesion or prevent its appearance in treated patients even when they experience immunosuppressive conditions