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Background/purpose: Increasing the bond strength between the orthodontic brackets and all-ceramic materials is one of the challenges facing orthodontists. The purpose of this study is to assess the shear bond strength (SBS) of metal brackets to two types of all ceramic materials using various surface mechanical and chemical conditioning methods. Materials and methods: Sixty ceramic blocks were prepared using two types of all ceramic materials (IPS e.max and VITA Suprinity® PC) and treated with 3 surface treatments; surface etching with 9.6% hydrofluoric acid (HFA) for 2 mins; surface roughening with Sof-Lex finishing discs; and surface roughening with Sof-Lex finishing discs and etching with HFA. Metal brackets were attached to the surface of the ceramic blocks using light cure orthodontic adhesive. Samples were subjected to 2000 thermo-cycles (5–50 °C) and the SBS was assessed using Instron machine. The adhesive remnant index (ARI) was evaluated under light microscope. Descriptive and group comparison were calculated using Two-way ANOVA, Post-hoc Tukey's and Chi-square tests and significance level set at (P

Intact and non-intact urinary stones richening with calcium oxalate were collected and characterized. The elemental analysis, phase quantifications, and function groups were determined by different spectroscopic techniques, namely: energy-dispersive X-ray fluorescence (EDXRF), the synchrotron radiation X-ray diffraction (SR-XRD), and attenuated total reflection Fourier transform infrared (ATR-FTIR). The quantitative analysis of twenty elements was demonstrated in the most of the urinary stones and these elements are: Ca, Na, P, S, Mg, Cl, Zn, K, Ti, Sr, Ni, Co, Fe, Cu, Cd, Br, Pb, Se, I, and Mn. Using the Rietveld method, the diffraction phase quantification was illustrated. The main found phases are calcium oxalate (monohydrate and dihydrate) and hydroxyapatite phase. The FTIR outcomes reveal that the functional groups of O–H, N–H, C=O, and C–O indicate to the calcium oxalate whereas the P–O and O–P–O, and PO43− groups indicate to the calcium phosphates in the hydroxyapatite. A considerable correlations between the oxalate urinary stones and the group of elements were found. These elements are Zn, Sr, Ni, and Fe. These correlations could lead to new therapeutic approaches. Furthermore, the elements of sodium and chlorine have no vital role in the formation of calcium oxalate urinary stones.

The pressed powder sample is a common method for elemental analysis using X-ray fluorescence analysis whereas suitable light hydrocarbon materials should be added to the sample as a binder. The present study demonstrates the applicability of using different commercial binders for elemental analysis of urinary stone samples. In order to confirm the obtained results, a comparison with pure chemical grade binders was presented. Different commercial and pure binders were tested for quantitative elemental analysis of urinary stones, namely, cellulose, starch, wax, and urea. Energy dispersive X-ray fluorescence (EDXRF) was used for elemental analysis. Differential thermal analysis was used to estimate the loss on ignition (LOI) in the urinary stone samples. The signal to background ratios (I/IB) of the different detected elements in the commercial and pure binders were calculated, compared, and studied at eight different photon energies starting from 2.5 up to 37 keV. Standard-less quantitative analysis method based on the fundamental parameter approach was applied for elemental analysis of selected urinary stones. The commercial and low-cost binders could be an excellent alternative binder for urinary stone analysis using energy dispersive X-ray fluorescence. The commercial binders could provide an advantage as pure chemical grade binders or even better especially at photon energy higher than 10 keV. The best commercial binder candidate was found to be the wax. The quantitative analysis results using commercial and pure chemical grade binders give good agreement results, which indicate the applicability of commercial binders for quantitative elemental analysis of urinary stones in the form of pressed powder samples.

Intact and non-intact urinary stones richening with calcium oxalate were collected and characterized. The elemental analysis, phase quantifications, and function groups were determined by different spectroscopic techniques, namely: energy-dispersive X-ray fluorescence (EDXRF), the synchrotron radiation X-ray diffraction (SR-XRD), and attenuated total reflection Fourier transform infrared (ATR-FTIR). The quantitative analysis of twenty elements was demonstrated in the most of the urinary stones and these elements are: Ca, Na, P, S, Mg, Cl, Zn, K, Ti, Sr, Ni, Co, Fe, Cu, Cd, Br, Pb, Se, I, and Mn. Using the Rietveld method, the diffraction phase quantification was illustrated. The main found phases are calcium oxalate (monohydrate and dihydrate) and hydroxyapatite phase. The FTIR outcomes reveal that the functional groups of O-H, N-H, C=O, and C-O indicate to the calcium oxalate whereas the P-O and O-P-O, and PO

Finasteride is an orally active testosterone 5-alpha-reductase inhibitor that is used for the treatment of benign prostatic hyperplasia as a surgical alternative. The aim of this work was to improve finasteride levels in plasma and prostate through the formulation of biodegradable finasteride nanoparticles and to quantify finasteride levels using near-infrared application. Finasteride nanoparticles were prepared by emulsion solvent evaporation method utilizing the biodegradable polymers poly(lactic- co-glycolic acid) and poly-ϵ-caprolactone. The prepared nanoparticles were characterized by particle size, zeta potential, and encapsulation efficiency. The selected finasteride-biodegradable formula was examined in vivo, and both plasma and prostate levels of finasteride were quantified utilizing near-infrared technique. Results revealed that the prepared finasteride nanoparticles size range was from 231 ± 78 to 956 ± 224 nm with finasteride–poly-ϵ-caprolactone nanoparticles showing larger particle sizes compared with finasteride–poly(lactic- co-glycolic acid) nanoparticles. The encapsulation efficiency ranged from 68.89% ± 2.99% to 99.15% ± 4.32%. The selected formula of finasteride nanoparticles showed improved levels of finasteride in both plasma and prostate of the investigated rats. The realization of sustained release of biodegradable finasteride nanoparticles for possible oral or parenteral application could improve the activity of the drug for sustaining release time with lower dosing recurrence that improves patient compliance.

The purpose of this research work is to evaluate the effects of reinforcing high impact polystyrene (HIPS’s) with multiwall carbon nanotubes (MWCNTs) on the mechanical performance and the water absorption resistance. The significant changes in HIPS/MWCNTs nanocomposite on the mechanical performance and water absorption resistance were investigated with different weight percentage of MWCNTs in the range of 0.10 wt% to 10 wt%.

This paper presents the study of rheological and thermal behaviour of high impact polystyrene/multiwall carbon nanotubes (HIPS/MWCNTs) nanocomposite. The nanocomposite was prepared via melt mixing method. The influence of different loadings of MWCNTs on the HIPS viscosity and other rheological characteristics were analyzed experimentally. Other rheological characteristics were studied using dynamic analysis of viscosity through rotational rehometer. Glass transition temperature (Tg) were also investigated using non-isothermal differential scanning calorimeter analysis. The viscosity was found to be directly proportional to MWCNTs’ loading, up to five times the value of pure HIPS at loading level of 7.5wt% of MWCNTs. The MWCNTs loading demonstrated a marginal effect (1-2%) on the Tg.

Retrocaval ureter is a rare congenital anomaly. We report a 31-year-old woman who presented with dull aching pain in the right flank that was exaggerated in the past few months. Diagnosis was made on intravenous urography, which showed proximal ureteric dilatation and hydronephrosis. Retrograde ureteropyelogram showed typical “S-” shaped or fish hook deformity in the dilated proximal ureteric segment with moderate hydronephrosis. The patient underwent an ureteroureterostomy with anteriorization of ureter.

Background Sub-clinical hypothyroid dysfunction, a relatively understudied disorder in the Kingdom of Saudi Arabia (KSA), has significant clinical implications if not properly monitored. Also from KSA, more than 50% of the population suffer from hypovitaminosis D ( Methods A total of 94 consenting adult Saudis [52 controls (without subclinical hypothyroidism), 42 cases (previously diagnosed subjects)] were included in this cross-sectional study. Anthropometrics were obtained and fasting blood samples were taken for ascertaining lipid and thyroid profile, as well as measuring PTH, 25(OH) vitamin D and calcium. Results Cases had a significantly higher body mass index than the controls (p p = 0.001). A significant positive association between HDL-cholesterol and PTH (R = 0.56; p = 0.001), as well as a negative and modestly significant negative association between LDL-cholesterol and PTH (R = - 20.0; p = 0.04) were observed. FT3 was inversely associated with circulating 25 (OH) vitamin D (R = -0.25; p = 0.01). Conclusions Patients with hypothyroid dysfunction possess several cardiometabolic risk factors that include obesity and dyslipidemia. The association between PTH and cholesterol levels as well as the inverse association between vitamin D status and FT3 needs to be reassessed prospectively on a larger scale to confirm these findings.