Effect of preoperative systemic capsaicin on tooth sensitivity after in-office bleaching: A pilot study.

Background: Tooth bleaching sensitivity (TBS) after bleaching procedures is a common problem. This study was undertaken to determine the effect of preoperative systemic capsaicin on tooth sensitivity (TS) after in-office bleaching procedures. Materials and Methods: Thirty participants received the treatment in this clinical trial. The subjects were randomly assigned to two groups (n = 15). Placebo and 0.25% capsaicin were administered three times daily for 24 h, with the first dose being administrated 1 h before the bleaching procedure. The subjects underwent two bleaching sessions at a 2-week interval by applying 40% hydrogen peroxide gel on six upper anterior teeth. A visual analog scale (VAS) was used to evaluate TS. Data were analyzed with SPSS 24. Statistical analyses were carried out with the Wilcoxon test and paired t-test. Statistical significance was set at P ≤ 0.05. Results: In the capsaicin group, there was a significant increase in TBS between the immediate and 1-h postoperative intervals and a significant decrease between 1- and 24-h postoperative intervals (P = 0.01 and P = 0.000, respectively). In the placebo group, there was a significant decrease between immediate and 24-h and between 1- and 24-h postoperative intervals (P = 0.007, P = 0.02). Milder TS was detected in the placebo group 24 h after bleaching (P < 0.05). Conclusion: Under the limitations of this study, preoperative use of systemic capsaicin did not significantly affect TS after the in-office bleaching procedure.

The effects of Astragalus polysaccharides, tragacanthin, and bassorin on methotrexate-resistant acute lymphoblastic leukemia.

Background and purpose: One strategy to overcome methotrexate (MTX) resistance in acute lymphoblastic leukemia is suppressing MDR1 expression. It has been proved Astragalus polysaccharides (APS) exert their anticancer effect by reversing drug resistance. Due to the structural similarity of tragacanthin and bassorin with APS, we aimed to investigate the effects of the aforementioned polysaccharides on the expression of the MDR1 gene in the MTX-treated CCRF-CEM cells. Experimental approach: Cytotoxicity of APS, bassorin, and tragacanthin on CCRF-CEM, CCRF-CEM/MTX (cells treated with MTX at IC50), and CCRF-CEM/R cells (CCRF-CEM cells resistant to MTX) was evaluated by MTT assay. The effect of all three compounds on MDR1 expression was evaluated using RT-PCR. Findings/Results: All the concentrations of tragacanthin, bassorin, and APS (except at 0.8-100 µg/mL in CCRF-CEM) decreased the viability of all the cells compared to the negative control group; and against the positive control (MTX-treated cells), only bassorin at 20-100 µg/mL in CCRF-CEM/R and tragacanthin at 50 and 100 µg/mL in CCRF-CEM/MTX and at 2-100 µg/mL in CCRF-CEM/R decreased cell viability. Tragacanthin diminished MDR1 expression in CCRF-CEM/MTX and CCRF-CEM/R cells, which MTX had already induced. Conclusion and implication: According to the results of this study, tragacanthin was a potent cytotoxic agent against CCRF-CEM cells and enhanced the chemosensitivity of CCRF-CEM/MTX and CCRF-CEM/R cells to MTX by down-regulation of MDR1 gene expression. Therefore, it could be a promising compound against cancer. Other possible mechanisms of action of tragacanthin should be evaluated and further in vitro and in vivo investigations are required.

Evaluation of Cytotoxic Effect of Different Extracts of Seidlitzia rosmarinus on HeLa and HepG2 Cell Lines.

BACKGROUND: Seidlitzia rosmarinus which is commonly called "Oshnan" or "Eshnan" in Persian belongs to Chenopodiaceae family. Conventionally, it is believed that this plant is toxic. This study was aimed to evaluate the cytotoxic effect of S. rosmarinus against HeLa and HepG2 cell lines. MATERIALS AND METHODS: S. rosmarinus was collected from the desert near Yazd, Iran. Hexane, chloroform, chloroform/methanol (9:1), and butanol extracts of aerial parts of S. rosmarinus were prepared. Doxorubicin and dimethyl sulfoxide 10% were used as positive and negative control, respectively. The cytotoxic activity was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. RESULTS: All extracts significantly and concentration dependently reduced viability of HeLa and HepG2 cells. Hexane, chloroform, and butanol extracts at doses of 200, 500, 750, and 1000 µg/ml significantly reduced HeLa cell viability (P < 0.05). Chloroform/methanol extract at doses of 100-500 µg/ml significantly reduced HeLa cell viability (P < 0.05). Hexane, chloroform, and butanol extracts at doses of 500, 750, and 1000 µg/ml significantly reduced HepG2 cell viability (P < 0.05). Chloroform/methanol extract at doses of 200, 300, 400, and 500 µg/ml significantly reduced HepG cell viability (P < 0.05). The most cytotoxic extract was chloroform/methanol extract in both cell lines. Furthermore, in the both cell lines, the second potent extract was chloroform extract. CONCLUSIONS: It can be concluded from the findings of this study that S. rosmarinus is a good candidate for further study to find new cytotoxic agents. Phytochemical investigation on chloroform/methanol extract and their structures is recommended.

Phytochemical Screening and Cytotoxic Evaluation of Euphorbia turcomanica on Hela and HT-29 Tumor Cell Lines.

BACKGROUND: Cancer is a term for a large group of different diseases, all involving uncontrolled cell growth. Many of Euphorbiaceae plants have been traditionally used for the treatment of ulcers, tumors, warts, and other diseases. In addition, in the last decade, there are studies showing cytotoxic effects of different species of Euphorbia on tumor cell lines. In this study, we attempted to determine if Euphorbia turcomanica possess any cytotoxic activity. MATERIALS AND METHODS: Solvents extracted the plant powder with various polarities by a maceration method, and qualitative phytochemical analyzes were carried out on them to identify the constituents. On the other hand, the possible cytotoxicity of different extracts on Hela and HT-29 tumor cells was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and 50% reduction in cell survival was considered as a cytotoxic effect. Analyze of variance followed by Student-Newman-Keuls test was used to see the differences among the groups. RESULTS: Phytochemical analysis of E. turcomanica showed the presence of flavonoid, alkaloid, anthraquinone and tannin in plant aerial parts. Methanol-water, acetone, dichloromethane, methanol, and heptane extracts of E. turcomanica significantly reduced viability of Hela cells (P < 0.05) with inhibitory concentration 50% (IC50) of 50, 90, 230, 420, and 450 µg/ml, respectively. While methanol-water, dichloromethane, methanol, ethyl acetate, and heptane extracts were cytotoxic with IC50 of 43, 115, 125, 250, and 390 µg/ml, respectively (P < 0.05), on HT-29 cells. CONCLUSION: It can be concluded that E. turcomanica is a good candidate for further study toward cytotoxic agents.

Production and Characterization of New Anti-HER2 Monoclonal Antibodies.

Breast cancer is a major public health problem worldwide. Although in Iran cancer is the third cause of death after coronary heart disease and accidents, mortality from cancer has been on the rise during recent decades. About 15% to 20% of patients with invasive breast cancer have abnormally high levels of HER2 protein. HER2 is a specialized protein found on breast cancer cells that controls cancer growth and spread. This study describes the generation and characterization of new anti-HER2 MAbs towards HER2 protein using a chimeric peptide immunogen containing discontinuous B-cell epitope peptide (peptide 626) and promiscuous T-helper epitope (MVF). The specificity of these MAbs was confirmed in various immunoassays, including ELISA, Western blotting, and immunofluorescence. Moreover, the MTT assay results indicated that 5H5 and 5H11 MAbs could reduce the growth of SKBR3 cells by approximately 50% (p<0.05). These MAbs that can reduce cancer cell proliferation would be useful for cancer therapy. Furthermore, the synthetic peptide used in the current work was able to induce the immune system to generate antibodies, especially IgG isotype. Therefore, it could be further used as a peptide cancer vaccine that targets different epitopes or structural domains of HER2 ECD.

Immunization with a novel chimeric peptide representing B and T cell epitopes from HER2 extracellular domain (HER2 ECD) for breast cancer.

Because of direct stimulating immune system against disease, vaccination or active immunotherapy is preferable compared to passive immunotherapy. For this purpose, a newly designed chimeric peptide containing epitopes for both B and T cells from HER2 ECD subdomain III was proposed. To evaluate the effects of the active immunization, a discontinuous B cell epitope peptide was selected based on average antigenicity by bioinformatics analysis. The selected peptide was collinearly synthesized as a chimera with a T helper epitope from the protein sequence of measles virus fusion (208-302) using the GPSL linker. Three mice were immunized with the chimeric peptide. Reactive antibodies with HER2 protein in ELISA and immunofluorescence assays with no cross-reactivity were generated. The 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay indicated that the anti-peptide sera had inhibitory effects on proliferation of SK-BR-3 cells. Hence, the newly designed, discontinuous chimeric peptide representing B and T cell epitopes from subdomain III of HER2-ECD can form the basis for future vaccines design, where these data can be applied for monoclonal antibody production targeting the distinct epitope of HER2 receptor compared to the two broadly used anti-HER2 monoclonal antibodies, Herceptin and pertuzumab.

Cytotoxicity of different extracts of arial parts of Ziziphus spina-christi on Hela and MDA-MB-468 tumor cells.

BACKGROUND: It has been shown that plants from the family Rhamnaceae possess anticancer activity. In this study, we sought to determine if Ziziphus spina-christi, a species from this family, has cytotoxic effect on cancer cell lines. MATERIALS AND METHODS: Using maceration method, different extracts of leaves of Z. spina-christi were prepared. Hexane, chloroform, chloroform-methanol (9:1), methanol-water (7:1) methanol, butanol and water were used for extraction, after preliminary phytochemical analyses were done. The cytotoxic activity of the extracts against Hela and MDA-MB-468 tumor cells was evaluated by MTT assay. Briefly, cells were seeded in microplates and different concentrations of extracts were added. After incubation of cells for 72 h, their viability was evaluated by addition of tetrazolium salt solution. After 3 h medium was aspirated, dimethyl sulfoxide was added and absorbance was determined at 540 nm with an ELISA plate reader. Extracts were considered cytotoxic when more than 50% reduction on cell survival was observed. RESULTS: Hexane, chloroform, chloroform-methanol, butanol, methanol-water and aqueous extracts of Z. spina-christi significantly and concentration-dependently reduced viability of Hela and MAD-MB-468 cells. In the both cell lines, chloroform-methanol extract of Z. spina-christi was more potent than the other extracts. RESULTS: From the finding of this study it can be concluded that Z. spina-christi is a good candidate for further study for new cytotoxic agents.

Phytoremediation of benzene, toluene, ethylbenzene and xylene contaminated air by D. deremensis and O. microdasys plants.

BACKGROUND: People usually spent about 90% of their time indoors, which are probably more polluted than outside the buildings. High levels of volatile organic compounds (VOCs) are known as causes of sick building syndrome. The present study was designed to determine the quantitative effects of some plants to improve the quality of the environmental air. RESULTS: D. deremensis and O. microdasys were chosen for the present study. There is no report of using O. microdasys for cleaning the air from pollutants. So, in this study, the effectiveness of O. microdasys in air removing from pollutants was studied and compared with D. dermensis.O. microdasys plant can remove 2 ppm concentration benzene, toluene, xylene and ethylbenzene from air in test chambers completely after 48, 55, 47 and 57 hours, respectively. The removal rates of benzene, toluene, xylene and ethylbenzene (BTEX) from air in the test chambers were 1.18, 0.54, 1.64 and 1.35 mg/ m2d1, respectively. CONCLUSIONS: If an office containing 2.5 ppm of each of BTEX and had an approximate volume of 30 m3, it contains 16, 8, 22 and 22 mg/m3 benzene, toluene, xylene and ethylbenzene, respectively. Using ten O. microdasys pots with the same size used in this study, can remove benzene, toluene, xylene and ethylbenzene totally after 36, 40, 30 and 39 hours.The authors recommended studying the efficiency of the plants for removal of BTEX from air at higher range of concentrations such as 20-30 ppm.

Comparing different sterol containing solid lipid nanoparticles for targeted delivery of quercetin in hepatocellular carcinoma.

Quercetin (QT) is a potential chemotherapeutic drug with low solubility that seriously limits its clinical use. The aim of this study was enhancing cellular penetration of QT by sterol containing solid lipid nanoparticles (SLNs) which make bilayers fluent for targeting hepatocellular carcinoma cells. Three variables including sterol type (cholesterol, stigmasterol and stigmastanol), drug and sterol content were studied in a surface response D-optimal design for preparation of QT-SLNs by emulsification solvent evaporation method. The studied responses included particle size, zeta potential, drug loading capacity and 24 h release efficiency (RE24%). Scanning electron and atomic force microscopy were used to study the morphology of QT-SLNs and their thermal behavior was studied by DSC analysis. Cytotoxicity of QT-SLNs was determined by MTT assay on HepG-2 cells and cellular uptake by fluorescence microscopy method. Optimized QT-SLNs obtained from cholesterol and QT with the ratio of 2:1 that showed particle size of 78.0 ± 7.0 nm, zeta potential of -22.7 ± 1.3 mV, drug loading efficiency of 99.9 ± 0.5% and RE24 of 56.3 ± 3.4%. IC50 of QT in cholesterol SLNs was about six and two times less than free QT and phytosterol SLNs, respectively, and caused more accumulation of QT in HepG2 cells. Blank phytosterol SLNs were toxic on cells.

The effect of aspartate-lysine-isoleucine and aspartate-arginine-tyrosine mutations on the expression and activity of vasopressin V2 receptor gene.

BACKGROUND: Vasopressin type 2 receptor (V2R) plays an important role in the water reabsorption in the kidney collecting ducts. V2R is a G protein coupled receptor (GPCR) and the triplet of amino acids aspartate-arginine-histidine (DRH) in this receptor might significantly influence its activity similar to other GPCR. However, the role of this motif has not been fully confirmed. Therefore, the present study attempted to shed some more light on the role of DRH motif in G protein coupling and V2R function with the use of site-directed mutagenesis. METHODS: Nested PCR using specific primers was used to produce DNA fragments containing aspartate-lysine-isoleucine and aspartate-arginine-tyrosine mutations with replacements of the arginine to lysine and histidine to tyrosine, respectively. After digestion, these inserts were ligated into the pcDNA3 vector and transformation into E. coli HB101 was performed using heat shock method. The obtained colonies were analyzed for the presence and orientation of the inserts using proper restriction enzymes. After transient transfection of COS-7 cells using diethylaminoethyl-dextran method, the adenylyl cyclase activity assay was performed for functional study. The cell surface expression was analyzed by indirect ELISA method. RESULTS: The functional assay indicated that none of these mutations significantly altered cAMP production and cell surface expression of V2R in these cells. CONCLUSION: Since some substitutions in arginine residue have shown to lead to the inactive V2 receptor, further studies are required to define the role of this residue more precisely. However, it seems that the role of the histidine residue is not critical in the V2 receptor function.

Effects of silymarin on the proliferation and glutathione levels of peripheral blood mononuclear cells from beta-thalassemia major patients.

Iron toxicity in beta-thalassemia major is the main cause of oxidative stress and cell mediated immune deficiencies. Despite indicative signs of severe oxidative deficiencies associated with beta-thalassemia major, such as decreased level of plasma antioxidants and depletion of erythrocyte glutathione, little is known about intracellular redox status of immune cells. Since glutathione is a primary intracellular antioxidant and plays an essential role in several functions in T cells, in this study intracellular glutathione (GSH) levels as well as proliferation of PHA-activated peripheral blood mononuclear cells (PBMC) were investigated in 28 beta-thalassemia major patients and 28 healthy age-matched individuals. Considering the potential benefits of flavonoids in the therapy of oxidative stress, the effects of silymarin on the GSH levels and proliferation of PBMC from normal and thalassemia individuals were further examined. Quantitative determination of intracellular GSH and proliferative response of PBMC to PHA were performed before and after 72 h incubation of PBMC with various concentrations of silymarin (0, 5, 10, or 20 mug/ml). Results demonstrated a significant reduction of GSH and proliferation in beta-thalassemia major cells; however treatment with silymarin led to restoration of both GSH levels and PBMC proliferation in thalassemia patients. Considerably low levels of GSH and depressed proliferative response of PBMC in beta-thalassemia major may be responsible for the cell mediated immune abnormalities in iron overload conditions. Moreover, the GSH restoration and improvement of PBMC growth by silymarin is a possible explanation for its recently reported antioxidant and immunostimulatory activities. These data suggest the benefit of using flavonoids to normalize immune dysfunction in beta-thalassemia major. The immunomodulatory effects of silymarin in beta-thalassemia major are currently under further investigation in a double blind clinical trial.

Cytotoxic Evaluations of Iranian Conifers on Cancer Cells.

In this study, branchlets, fruit, or bark of Taxus baccata. L. as well as branchlets or fruits of two other species of Iranian conifers, namely, Platycladus orientalis. France and Cupressus sempervirens. L. var. horizentalis. (Mill) Gunde were collected, identified, and the cytotoxic effects of hydroalcoholic extracts on three human tumor cell lines were determined. Different concentrations of extracts were added to cultured cells and incubated for 72 h. Cell survival was evaluated using the MTT assay. Extracts from bark of female Taxus baccata. showed inhibitory activities against Hela cells. The extracts of the branchlets of male and female T. baccata. as well as obtained extract from fruits of P. orientalis. showed inhibitory activities against MDA-MB-468 cells, whereas the extracts of branchlets of female T. baccata. showed inhibitory activities against KB cells. In conclusion, obtained extract from bark of T. baccata. showed comparable cytotoxic effect to doxorubicin against Hela cells.

Fibrinolytic effects of Ginkgo biloba extract.

A multitude of factors are involved in regulating the blood coagulation homeostatic processes in the body, which may ultimately lead to thromboemboli and thrombosis. The resolution of blood clots after healing is as important as clot formation at the site of a vascular lesion. This is accomplished by fibrinolytic drugs such as streptokinase (SK) and urokinase.It must be noted that administration of SK may be accompanied by the lysis of blood clots in unwanted sites, and complications such as general lytic conditions, severe hemorrhaging, reduced serum fibrinogen and allergies can occur. Anti-SK antibodies neutralize the effects of SK. Studies on natural compounds and medicinal herbs with fewer side effects have been ongoing. In the present study, the fibrinolytic effect of Ginkgo biloba, an herb grown in Iran, was investigated.A polyphenolic method was used to obtain Ginkgo extract from its leaves. The fibrinolytic effects of SK (positive control) were compared with those of Ginkgo extract using a fluorometry method.In producing a labelled clot, fibrinogen was labelled with the fluorescent agent fluorescein isothiocyanate and precipitated in the presence of Ca(2+). SK (100 U/mL to 1000 U/mL) and Ginkgo extract were added to labelled fibrin in a plasma environment at dilutions of 1, 1:10, 1:100 and 1:1000 (volume/volume). The fluorescence of the solution was measured between 15 min and 60 min later.A linear relationship was observed between the fluorescence measured and SK concentrations ranging from 300 U/mL to 700 U/mL. Ginkgo extract displayed a remarkable effect in resolving the clot. As Ginkgo extract remained in the environment, fluorescence increased notably, showing a time-dependent relationship.Overall, the results indicate that the effects of Ginkgo extract on the fibrinolytic system are similar to those of SK; hence, this herbal extract can be used as a complement to or a substitute for SK. Additionally, it is proposed that the effects of the active ingredients of Ginkgo extract should be studied in animals. Further studies are warranted for evaluating the possible side effects and toxicity of Ginkgo extract in human subjects.