Staphylococcus aureus enterotoxin b down-regulates the expression of transforming growth factor-beta (TGF-β) signaling transducers in human glioblastoma

Background: It has been revealed that Staphylococcus aureus enterotoxin B (SEB) may feature anti-cancer and anti-metastatic advantages due to its ability to modify cell immunity processes and signaling pathways. Glioblastoma is one of the most aggressive human cancers; it has a high mortality nature, which makes it an attractive area for the development of novel therapies. Objectives: We examined whether the SEB could exert its growth inhibitory effects on glioblastoma cells partially through the manipulation of a key tumor growth factor termed transforming growth factor-beta (TGF-β). Materials and Methods: A human primary glioblastoma cell line, U87, was treated with different concentrations of SEB. The cell quantity was measured by the MTT assay at different exposure times. For molecular assessments, total ribonucleic acid (RNA) was extracted from either non-treated or SEB-treated cells. Subsequently, the gene expression of TGF-β transducers, smad2/3, at the messenger RNA (mRNA) level, was analyzed via a quantitative real-time polymerase chain reaction (qPCR) using the SYBR Green method. Significant differences between cell viability and gene expression levels were determined (Prism 5.0 software) using a one-way analysis of variance (ANOVA) test. Results: We reported that SEB could effectively down-regulate smad2/3 expression in glioblastoma cells at concentrations as quantity as 1 µg/mL and 2 µg/mL (P < 0.05 and P < 0.01, respectively). The SEB concentrations effective at regulating smad2/3 expression were correlated with those used to inhibit the proliferation of glioblastoma cells. Our results also showed that SEB was able to decrease smad2/3 expression at the mRNA level in a concentration- and time-dependent manner. Conclusions: We suggested that SEB could represent an agent that can significantly decrease smad2/3 expression in glioblastoma cells, leading to moderate TGF-β growth signaling and the reduction of tumor cell proliferation. © 2016, Ahvaz Jundishapur University of Medical Sciences

Aloe barbadensis: how a miraculous plant becomes reality

Aloe barbadensis Miller is a plant that is native to North and East Africa and has accompanied man for over 5,000 years. The aloe vera plant has been endowed with digestive, dermatological, culinary and cosmetic virtues. On this basis, aloe provides a range of possibilities for fascinating studies from several points of view, including the analysis of chemical composition, the biochemistry involved in various activities and its application in pharmacology, as well as from horticultural and economic standpoints. The use of aloe vera as a medicinal plant is mentioned in numerous ancient texts such as the Bible. This multitude of medicinal uses has been described and discussed for centuries, thus transforming this miracle plant into reality. A summary of the historical uses, chemical composition and biological activities of this species is presented in this review. The latest clinical studies involved in vivo and in vitro assays conducted with aloe vera gel or its metabolites and the results of these studies are reviewed

Purification And Characterization Of Cell Wall Mannoproteins Of Candidaalbicans Using Intact Cell Method

Virulence of the opportunistic yeast, Candida albicans , involves the interplay of many complex changes including the yeast-hyphae transition, which mainly involves protein changes. Cell wall mannoproteins are found to be the main cause of adherence of C. albicans to epithelial cells in the first step of an infection process. In the present study, cell wall mannoproteins of intact yeast were purified using a simple treatment of yeast with mercaptoethanol and sodium dodecyl sulfate followed by Concanavalin A chromatography. Both electrophoretic analysis of the column effluent and Western blot analysis using polyclonal and monoclonal antibodies showed the presence of mannoproteins with molecular weight in the range of 30-50 kDa. Dot blot analysis of the purified antigen with the polyclonal and monoclonal antibodies prepared in this study showed that outer membrane mannoprotein antigens were obtained successfully following the above simple purification strategy

Evaluation of the Effects of Incubation Temperature and Ph On the Susceptibility of Candida Albicans Isolates to Ketoconazole Invitro

Introduction: Candidiasis, as an opportunistic infection, is caused by the Candida species. Although Candida albicans is classified in the body as an endogenic flora, it plays an important role in creating Candida related diseases. Candida vulvovaginitis in pregnant women, diabetes mellitus patients and those using multiple antibiotics and contraceptive drugs demonstrates the high resistance of the organism against conventional medication. On the other hand, recurrent vaginitis disintegrates the long-term process of treatment in majority of the patients. The present research was done with the aim of determining the optimum conditions for susceptibility testing before retreatment of patients. Methods: 10 isolates of Candida albicans obtained from 31 suspected patients suffering from recurrent Candida vaginitis were incubated with ketoconazole at two pH of 7.2 and 5.5 and two temperatures of 35ºC and 27ºC. The Microdilution broth test technique was used. The RPMI 1640 medium within the 96 well microplates with range of 12 tests was used to determine the MIC50 , MIC90 and MFC of the drug. Results: The obtained MIC50, MIC90 and MFC for ketoconazole at these conditions (T=35ºC and pH=7.2) were 0.25 to 1 µg/ml, 1 to 4 µg/ml and 64 to ≥ 512 µg/ml respectively, while these values at 27ºC, pH 5.5 were 1 to 8 µg/ml, 8 to 64 µg/ml and 512 to ≥ 512 µg/ml, at 35ºC and pH 5.5 the values were 1 to 8 µg/ml, 4 to 32 µg/ml, 256 to ≥ 512 µg/ml, while at 27ºC and pH 7.2 the values were 1 to 2 µg/ml, 8 to 32 µg/ml, 128 to ≥ 512 µg/ml, respectively. Conclusion: The obtained results confirmed that conditions with temperature of 35ºC and pH 7.2 resulted in better treatment outcomes than other conditions

Antifungal effect of Echinophora platyloba on expression of CDR1 and CDR2 genes in fluconazole-resistant Candida albicans

Background: Several studies examined the effect of the Echinophora platyloba extract in treatment of azole-resistant Candida albicans clinical isolates. Objective: We investigated the effect of E. platyloba extract on expression of CDR1 and CDR2 genes in fluconazole-resistant clinical isolates of C. albicans using real-time PCR. Materials and Methods: The crude extract of E. platyloba was obtained using percolation method. Using serial dilution method, different concentrations of extract were achieved. Two hundred microlitres of fungal suspension (106 CFU/ml) was added to the media and cultured with different concentrations and then incubated at 37 °C for 48 h. The concentration of extract in the first tube, which inhibited the growth of C. albicans, was recorded as the Minimal Inhibitory Concentration (MIC). In order to analyse the expression of CDR1 and CDR2 genes, RNA was extracted from C. albicans isolates before and after treatment with MIC of E. platyloba using glass beads and the denaturing buffer agents in an RNase-free environment and then the cDNA was synthesised and used for real-time PCR assay. Results: Twenty of total of 148 isolates were resistant to fluconazole. The MIC and MFC for the alcoholic extract of E. Platyloba were 64 mg/ml and 128 mg/ml, respectively. Real-time PCR results revealed that the mRNA levels of CDR1 and CDR2 genes significantly declined after incubation with E. Platyloba (both p values &lt; 0.001). Conclusion: E. Platyloba is effective in reducing CDR1 and CDR2 expression which in turn plays an important role in fluconazole resistance in Candida species. © 2016 British Journal of Biomedical Science