Solitary Plasmacytoma of the Parotid Gland with Crystalline Inclusions: A Case Report

Background  

Solitary extramedullary plasmacytoma of the parotid gland is a rare condition. Intracytoplasmic Crystalline inclusions in the tumor are even rarer and have been reported only once in the parotid gland.     

Current information on the association of Helicobacter pylori with autophagy and gastric cancer

Helicobacter pylori (H. pylori) is a Gram-negative bacterium and causative agent of gastric cancer. H. pylori induce defective autophagy or inhibit it by means of CagA and vacuolating cytotoxin A (VacA) toxins leading to the gastric cancer induction. Impaired or defective autophagy leads to the accumulation of cytotoxic materials, such as ROS and P62 that lead to increased mutations in the DNA, genome instability, and risk of cancer formation. H. pylori CagA may inhibit autophagy through the c-Met-PI3k/Akt-mTOR signaling pathway. However, VacA induces autophagy by some signaling pathways. In the gastric epithelial cells, VacA is a necessary and sufficient factor for the creation of autophagy. While CagA is a negative regulator of this phenomenon, the elimination of this gene from H. pylori has increased autophagy and the production of inflammatory cytokines is reduced. In gastrointestinal cancers, some of the microRNAs (miRNAs) act as tumor suppressors and some other are oncogenes by regulating various genes expression. H. pylori can also modify autophagy through a mechanism that includes the function of miRNAs. In autophagy, oncogenic miRNAs inhibit activation of some tumor suppressor signaling pathways (e.g., ULK1 complex, Beclin-1 function, and Atg4 messaging), whereas tumor suppressor miRNAs can block the activation of oncogenic signaling pathways. For instance, Beclin-1 is negatively regulated by miRNA-376b (oncogenic miRNA) and miRNA-30a (tumor suppressor miRNA). Similarly, Atg4 by miRNA-376b (oncogenic miRNA) and miRNA-101 (tumor suppressor miRNA). So, this apparent paradox can be explained as that both Beclin-1 and Atg4 play different roles in a particular cell or tissue.     

Smac mimetics as novel promising modulators of apoptosis in the treatment of breast cancer

Breast cancer is the most prevalent cancer in women. Despite improvements in treatment, the rate of breast cancer-related deaths is still high, and this issue needs further, accurate investigations. Although several treatment options are available, none of them are efficient for complete remission, particularly in advanced stages of the disease. It is known that cancerous cells have dysregulated apoptosis-related pathways, by which they can remain alive for a long time, expand freely, and escape from apoptosis-inducing drugs or antitumor immune responses. Therefore, modulation of apoptosis resistance in cancer cells may be an efficient strategy to overcome current problems faced in the development of immunotherapeutic approaches for the treatment of breast cancer. The inhibitors of apoptosis protein (IAPs) are important targets for cancer therapy because it has been shown that these molecules are overexpressed and highly active in various cancer cells and suppress apoptosis process in malignant cells by blockage of caspase proteins. There is evidence of Smac mimetics efficacy as a single agent; however, recent studies have indicated the efficacy of current anticancer immunotherapeutic approaches when combined with Smac mimetics, which are potent inhibitors of IAPs and synthesized mimicking Smac/Diablo molecules. In this review, we are going to discuss the efficacy of treatment of breast cancer by Smac mimetics alone or in combination with other therapeutics.     

A critical review on use of Agrobacterium rhizogenes and their associated binary vectors for plant transformation

Agrobacterium rhizogenes, along with A. tumefaciens, has been used to affect genetic transformation in plants for many years. Detailed studies conducted in the past have uncovered the basic mechanism of foreign gene transfer and the implication of Ri/Ti plasmids in this process. A number of reviews exist describing the usage of binary vectors with A. tumefaciens, but no comprehensive account of the numerous binary vectors employed with A. rhizogenes and their successful applications has been published till date. In this review, we recollect a brief history of development of Ri-plasmid/Ri-T-DNA based binary vectors systems and their successful implementation with A. rhizogenes for different applications. The modification of native Ri plasmid to introduce foreign genes followed by development of binary vector using Ri plasmid and how it facilitated rapid and feasible genetic manipulation, earlier impossible with native Ri plasmid, have been discussed. An important milestone was the development of inducible plant expressing promoter systems which made expression of toxic genes in plant systems possible. The successful application of binary vectors in conjunction with A. rhizogenes in gene silencing and genome editing studies which are relatively newer developments, demonstrating the amenability and adaptability of hairy roots systems to make possible studying previously intractable research areas have been summarized in the present review.     

Education based on the health belief model to improve the level of physical activity

[Purpose] This study aimed to investigate the effect of education based on the health belief model on the physical activity of the staff of the University of Medical Sciences.[Methods] This semi-experimental study was conducted on 130 university staff aged 25-50 years from the Hamadan University of Medical Sciences. Inclusion criteria were having at least 1 year of work experience, lack of acute and chronic physical and mental illnesses, and not using drugs that affect physical activity. The samples were randomly divided into two groups. The experimental group received three training sessions based on the health belief model. Before and 2 months after training, the control and experimental groups were evaluated via the following questionnaires: (1) demographic information questionnaire, (2) Health Belief Model Questionnaire, and (3) International Physical Activity Questionnaire. Finally, data were analyzed statistically.[Results] The training process resulted in a significant increase in the mean scores of the health belief model constructs in the experimental group, but changes in the control group were not significant. Self-efficacy was the strongest predictor of physical activity.[Conclusion] The health belief model is a useful model for improving individuals'' understanding of the benefits of physical activity.     

Effect of low-level laser therapy on experimental wounds of hard palate mucosa in mice

Under general anesthesia and sterile conditions, incision wound was induced in the hard palate mucosa of adult male mice. The wounds of groups 1 and 2 were irradiated daily with He-Ne laser at 3 and 7.5 J/cm2 for 120 and 300 s, respectively, while the incision wound of group 3 not exposed served as controls. On day 3 of injury, the laser-treated wounds contained significantly lower neutrophils than the wounds in the control group. By day 7 after injury, the laser-treated wounds contained significantly more fibroblasts and at the same time contained significantly fewer macrophages. In conclusion, an acceleration of the wound healing process of experimental wounds in the hard palate mucosa of mice at low-level laser therapy with a He-Ne laser at energy densities of 3 and 7.5 J/cm2 was observed.     

New insights into the roles and regulation of SphK2 as a therapeutic target in cancer chemoresistance

Chemoresistance is a complicated process developed by most cancers and accounts for the majority of relapse and metastasis in cancer. The main mechanisms of chemoresistance phenotype include increased expression and/or activated drug efflux pumps, altered DNA repair, altered metabolism of therapeutics as well as impaired apoptotic signaling pathways. Aberrant sphingolipid signaling has also recently received considerable attention in chemoresistance. Sphingolipid metabolites regulate main biological processes such as apoptosis, cell survival, proliferation, and differentiation. Two sphingosine kinases, SphK1 and SphK2, convert sphingosine to sphingosine-1-phosphate, an antiapoptotic bioactive lipid mediator. Numerous evidence has revealed the involvement of activated SphK1 in tumorigenesis and resistance, however, contradictory results have been found for the role of SphK2 in these functions. In some studies, overexpression of SphK2 suppressed cell growth and induced apoptosis. In contrast, some others have shown cell proliferation and tumor promotion effect for SphK2. Our understanding of the role of SphK2 in cancer does not have a sufficient integrity. The main focus of this review will be on the re-evaluation of the role of SphK2 in cell death and chemoresistance in light of our new understanding of molecular targeted therapy. We will also highlight the connections between SphK2 and the DNA damage response. Finally, we will provide our insight into the regulatory mechanisms of SphKs by two main categories, micro and long, noncoding RNAs as the novel players of cancer chemoresistance.     

Decellularized Wharton's jelly extracellular matrix as a promising scaffold for promoting hepatic differentiation of human induced pluripotent stem cells

Liver tissue engineering as a therapeutic option for restoring of damaged liver function has a special focus on using native decellularized liver matrix, but there are limitations such as the shortage of liver donor. Therefore, an appropriate alternative scaffold is needed to circumvent the donor shortage. This study was designed to evaluate hepatic differentiation of human induced pluripotent stem cells (hiPSCs) in decellularized Wharton's jelly (WJ) matrix as an alternative for native liver matrix. WJ matrices were treated with a series of detergents for decellularization. Then hiPSCs were seeded into decellularized WJ scaffold (DWJS) for hepatic differentiation by a defined induction protocol. The DNA quantitative assay and histological evaluation showed that cellular and nuclear materials were efficiently removed and the composition of extracellular matrix was maintained. In DWJS, hiPSCs-derived hepatocyte-like cells (hiPSCs-Heps) efficiently entered into the differentiation phase (G1) and gradually took a polygonal shape, a typical shape of hepatocytes. The expression of hepatic-associated genes (albumin, TAT, Cytokeratin19, and Cyp7A1), albumin and urea secretion in hiPSCs-Heps cultured into DWJS was significantly higher than those cultured in the culture plates (2D). Altogether, our results suggest that DWJS could provide a proper microenvironment that efficiently promotes hepatic differentiation of hiPSCs.     

Evaluation and optimization of factors affecting the performance of a flow-through system based on immobilized acetylcholineesterase as a biosensor

A flow-through system based on acetylcholineesterase (AChE) was studied. The system was prepared by mixing AChE and a multiwall carbon nanotube (MWCNT). Two important parameters, the ratios of AChE:MWCNT (X₁) and AChE-MWCNT:sol-gel (X₂) were optimized using response surface methodology. The results revealed that an enzyme immobilized within the MWCNT-sol-gel was more effective compared to one conducted with sol-gel. The optimum feed flow rate was 0.4 mL/min and ATChI concentration was found to be 1 mM. The optimum ratios of X₁ and X₂ for immobilization on ceramic packing were 1.07 and 0.43, respectively. The sensitivity of this flow-through system was 1.82 × 10⁻⁵/μM and long-term stability analyzed after 120 days was 74% of initial absorbance. With respect to an incubation time of 14 min, the detection limit for paraoxon was 7.3 × 10⁻¹² mol.