Phytochemical Screening and chemical investigation of lipoidal matter of the leaves of Latania verschaffeltii Lem. Family Arecaceae cultivated in Egypt

Abstract This study presents the first preliminary phytochemical screening and investigation of the lipoidal matter of Latania verschaffeltii Lem. leaves, belonging to the Arecaceae family. Gas chromatography coupled with mass spectroscopy (GC/MS) was used to analyze and identify compounds of saponifiable and unsaponifiable content. The preliminary phytochemical screening of total methanolic extract of Latania verschaffeltii Lem. leaves revealed the presence of unsaturated sterols and/or triterpenes, carbohydrates and/or glycosides, flavonoids, tannins, saponins, and phenolic acids in the leaves. However, cardenolides, cyanogenic compounds, alkaloids, and iridoids were not detected. The results of the gas chromatography/mass spectrometry (GC/MS) analysis indicated that the percentage of saturated fatty acids (83.82%) is higher than that of unsaturated fatty acids (9.42%). The predominant methyl ester of a saturated fatty acid detected in the sample was hexadecanoic acid methyl ester, accounting for 41.68% of the total. The composition of the unsaponifiable matter consisted of hydrocarbons (5.66%), fatty alcohols (0.96%), terpenes (85.97%), and sterols (2.18%). The major terpenes observed were phytol (43.62%) and squalene (39.27%).

Effect of phytic acid on bond strength and interfacial integrity of universal adhesive to deep dentin

Abstract This study investigated the effect of phytic acid (IP6) in different concentrations and application times on microtensile bond strength (µTBS) and interfacial integrity of universal adhesive to deep dentin. Flat deep dentin surfaces of 48 human molars were either etched with 37% phosphoric acid (PA) for 15 sec (control); or received no acid treatment and universal adhesive was applied directly in a self-etch mode (SE); or divided according to IP6 concentration (C) into two main groups: C1, 0.5%, and C2, 1%. Specimens of IP6 groups were further subdivided into three subgroups according to application time of IP6 (T) where; T1, 15 sec; T2, 30 sec and T3, 60 sec. Single Bond Universal Adhesive was then applied and resin composite blocks were built-up. Forty Specimens were then sectioned to produce resin/dentin beams that were used for µTBS testing using a universal testing machine. The remaining eight specimens were sectioned into slabs that were immersed into ammonical silver nitrate solution and nanoleakage was observed using a field emission scanning electron microscope (FE-SEM). The results showed that the application of IP6 in 0.5% and 1% produced significantly higher µTBS and less nanoleakage compared to PA and SE groups. Also, the application of IP6 for 60 sec recorded the highest µTBS and the lowest nanoleakage followed by 30 sec, and 15 sec respectively. Therefore, conditioning of deep dentin with IP6 enhances µTBS and interfacial integrity of universal adhesive to deep dentin in comparison to PA etching or using the universal adhesive in SE mode.

Resumo Este estudo investigou o efeito do ácido fítico (IP6) em diferentes concentrações e tempos de aplicação na resistência da ligação microtensiva (µTBS) e na integridade interfacial do adesivo universal à dentina profunda. As superfícies planas de dentina profunda de 48 molares humanos foram preparadas com ácido fosfórico (PA) a 37% durante 15 seg. (controlo); ou não receberam tratamento ácido e o adesivo universal foi aplicado diretamente em modo de auto-adesivo (SE); ou dividido de acordo com a concentração de IP6 (C) em dois grupos principais: C1, 0,5%, e C2, 1%. Os espécimes dos grupos IP6 foram ainda subdivididos em três subgrupos de acordo com o tempo de aplicação do IP6 (T) em que; T1, 15 seg; T2, 30 seg e T3, 60 seg. Aplicou-se então Single Bond Universal Adhesive e construíram-se blocos compostos de resina. Quarenta espécimes foram então seccionados para produzir feixes de resina/dentina que foram usados para testes µTBS usando uma máquina de testes universal. Os restantes oito espécimes foram seccionados em placas que foram imersas em solução amoniacal de nitrato de prata e observou-se uma nano-infiltração utilizando um microscópio eletrônico de varrimento de emissões de campo (FE-SEM). Os resultados mostraram que a aplicação de IP6 em 0,5% e 1% produziu µTBS significativamente mais elevado e menos nano-infiltração em comparação com os grupos PA e SE. Além disso, a aplicação de IP6 durante 60 seg registou o µTBS mais alto e o mais baixo de nano-infiltração seguido de 30 seg, e 15 seg respectivamente. Portanto, o condicionamento da dentina profunda com IP6 melhora o µTBS e a integridade interfacial do adesivo universal à dentina profunda em comparação com a gravação de PA ou utilizando o adesivo universal no modo SE.

Bond strength of three luting agents to zirconia ceramic - influence of surface treatment and thermocycling

OBJECTIVE: This in vitro study aimed to evaluate the influence of different surface treatments, 3 luting agents and thermocycling on microtensile bond strength (µTBS) to zirconia ceramic. Material and METHODS: A total of 18 blocks (5x5x4 mm) were fabricated from zirconia ceramic (ICE Zirkonia) and duplicated into composite blocks (Alphadent). Ceramic blocks were divided into 3 groups (n=6) according to the following surface treatments: airborne-particle abrasion (AA), silica-coating, (SC) (CoJet) and silica coating followed by silane application (SCSI) (ESPE Sil). Each group was divided into 3 subgroups (n=2) according to the 3 luting agents used. Resin-modified glass-ionomer cement (RMGIC, Ketac Cem Plus), self-adhesive resin cement (UN, RelyX Unicem) and adhesive resin cement (ML, MultiLink Automix) were used for bonding composite and zirconia blocks. Each bonding assembly was cut into microbars (10 mm long and 1±0.1 mm²). Seven specimens of each subgroup were stored in water bath at 37ºC for 1 week. The other 7 specimens were stored in water bath at 37ºC for 30 days then thermocycled (TC) for 7,500 cycles. µTBS values were recorded for each specimen using a universal testing machine. Statistical analyses were performed using a 3-way ANOVA model followed by serial 1-way ANOVAs. Comparison of means was performed with Tukey's HSD test at (α=0.05). RESULTS: µTBS ranged from 16.8 to 31.8 MPa after 1 week and from 7.3 to 16.4 MPa after 30 days of storage in water and thermocycling. Artificial aging significantly decreased µTBS (p<0.05). Considering surface treatment, SCSI significantly increased µTBS (p<0.05) compared to SC and AA. Resin cements (UN and ML) demonstrated significantly higher µTBS (p<0.05) compared to RMGIC cement. CONCLUSIONS: Silica coating followed by silane application together with adhesive resin cements significantly increased µTBS, while thermocycling significantly decreased µTBS.

Lindane-induced biochemical perturbations in rat serum and attenuation by omega-3 and Nigella sativa seed oil.

Lindane (-hexachlorocyclohexane, -HCH), a highly persistent organochlorine insecticide is neurotoxic at acute doses and has been reported to induce oxidative stress in cells and tissues. In this study, we investigated the antioxidant property of Nigella sativa seed oil (N.O) and omega-3 polyunsaturated fatty acids (3) against -HCH-induced oxidative hepatic and renal damage in male rats serum. Rats were orally given sublethal dose of -HCH (12 mg/kg, 24 h prior to decapitation), while N.O (0.3 ml/kg) and 3 (20 mg/kg) were given every 48 h for 20 days single or together, or also combined with -HCH. -HCH caused a significant increase in the levels of serum total lipids, cholesterol, and triglycerides by 49, 61 and 30% respectively, while HDL-cholesterol decreased by 45% compared to control group. Pretreatment with 3 and N.O prior -HCH administration re-established the altered biochemical features and alleviated the harmful effects of g-HCH on lipid profile. The concentration of serum total protein and albumin was significantly decreased by 35 and 45% respectively in rats treated with -HCH compared to control. -HCH also caused hepatic and renal damage, as observed from the elevated serum levels of urea, creatinine, total bilirubin and uric acid contents and aminotransferases (AST and ALT), phosphatases (ACP and ALP) and lactate dehydrogenase (LDH) activities. Co-administration of 3 and N.O reversed the hazardous effects induced by -HCH on the liver and kidney and also protected acetylcholinesterase from the inhibitory action of -HCH as well as suppressed the lipid peroxidation. Thus, the results show that 3 and N.O might prevent oxidative stress and attenuate the changes in the biochemical parameters induced by -HCH in male rats.

Influence of surface treatment and cyclic loading on the durability of repaired all-ceramic crowns

OBJECTIVE: This study investigated the durability of repaired all-ceramic crowns after cyclic loading. MATERIAL AND METHODS: Eighty In-ceram zirconia crowns were fabricated to restore prepared maxillary premolars. Resin cement was used for cementation of crowns. Palatal cusps were removed to simulate fracture of veneering porcelain and divided into 4 groups (n = 20). Fracture site was treated before repair as follows: roughening with diamond bur, (DB); air abrasion using 50 µm Al2O3, (AA) and silica coating using Cojet system followed by silane application, (SC). Control group (CG) 20 specimens were left without fracture. Palatal cusps were repaired using composite resin. Specimens were stored in water bath at 37ºC for one week. Ten specimens of each group were subjected to cyclic loading. Fracture load (N) was recorded for each specimen using a universal testing machine. Two-way analysis of variance (ANOVA) and Tukey honestly significant difference (HSD) test (a=.05) were used for statistical analysis. RESULTS: There was statistically significant difference between control and tested groups, (p<0.001). Post Hoc analysis with the Tukey HSD test showed that cyclic loading fatigue significantly decreased means fracture load of control and test groups as follows (CG, 950.4±62.6 / 872.3±87.4, P = 0.0004), (DB, 624.2 ±38 / 425.5± 31.7, P <.001), (AA, 711.5 ±15.5 / 490 ± 25.2, p <0.001) and (SC, 788.7 ± 18.1 / 610.2 ± 25.2, P <.001), while silica coating and silane application significantly increased fracture load of repaired crowns (p<0.05). CONCLUSION: Repair of fractured In-ceram zirconia crowns after chairside treatment of the fracture site by silica coating and silane application could improve longevity of repaired In-ceram zirconia crowns.