Sonodynamic therapy and common head and neck cancers: in vitro and in vivo studies.

Carcinogenesis is a complex multi-stage process associated with abnormal oncogenic signals in various signaling pathways. HNSCC (Head and neck squamous cell carcinoma) includes the majority of head and neck cancers (HNC). Also, HNSCC indicates a tumors heterogeneous group that derives from the squamous epithelium of the oropharynx, hypopharynx, oral cavity, and larynx. The main cancer management approach contains chemotherapy, radiation, and surgery separately or in combination. Each therapeutic approach has a limitation that influences cancer therapy procedures. Different treatment manners, stimuli-responsive therapeutic methods can improve on-target responses and reduce side effects. Sonodynamic therapy (ST) shows promising potential as an alternative treatment for cancer in the last few years. There is a hypothesis that shows ST using sonosenitizer in combination with low-intensity ultrasound (LIUS) could be useful in all kinds of cancer without focusing on specific target proteins, molecules, and/or genes. This review study discussed the application of ST for the treatment, ST mechanisms, and also, advances in the treatment of HNCs approaches in the recent decades.

Evaluation of the substitutions in 212, 342 and 215 amino acid positions in binding site of organophosphorus acid anhydrolase using the molecular docking and laboratory analysis.

OBJECTIVE: Organophosphorus Acid Anhydrolase (OPAA) is used as one of the most important enzymes in the decontamination process of organophosphate compounds. In this study, we aimed to evaluate the effects of amino acid substitution in OPAA's substrate-binding site on its catalytic activity using the rational engineering strategy. METHODS: The native and three mutant forms of OPAA enzyme including 4ZWP, 4ZWU and Mut6 were studied using the docking technique toward parathion, paraoxon and R-VX compounds. Furthermore, enzyme assay was performed on the native OPAA and Mut6 toward parathion. RESULTS: Docking results showed a decreased catalytic activity of the mutant forms toward parathion and paraoxon. Furthermore, enzyme assay showed in accordance with docking results a decreased activity of Mut6 compared to the native form. The results of docking prediction for R-VX showed an increased catalytic activity of 4ZWP and 4ZWU. 4ZWU had the highest activity, while the activity of Mut6 was lower than the native form. CONCLUSION: Amino acid positions of 212 and 342 seem to be important sites in the small pocket of OPAA affecting the enzyme catalytic activity. Therefore, substitution of these sites with appropriate amino acids depending on the substrate structure, can affect the enzyme catalytic efficiency (Tab. 2, Fig. 3, Ref. 30).

Rat lung decellularization using chemical detergents for lung tissue engineering.

Although pulmonary diseases account for a large number of deaths in the world, most have no treatment other than transplantation. New therapeutic methods for lung treatment include lung tissue engineering and regenerative medicine. Lung decellularization has been used to produce an appropriate scaffold for recellularization and implantation. We investigated 3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate (CHAPS) with sodium dodecyl sulfate (SDS) and Triton X-100 detergents for effecting rat lung decellularization. We evaluated using conventional histology, immunofluorescence staining and SEM methods for removing nuclear material while leaving intact extracellular matrix proteins and three-dimensional architecture. We investigated different concentrations of CHAPS, SDS and Triton X-100 for different periods. We found that 2 mM CHAPS + 0/1% SDS for 48 h was the best among the treatments investigated. Our method can be used to produce an appropriate scaffold for recellularization by stem cells and for investigations ex vivo and in vivo.

The effect of synthetic alginate sulfate hydrogels with recombinant PDGF-BB on Wound healing.

OBJECTIVE: Platelet-derived growth factor (PDGF-BB) is an important factor in the regeneration and wound healing. One of the problems is that there is not enough efficiency in the transmission or delivery of such factors in the wound site. In this study, alginate sulfate hydrogel was synthesized with recombinant PDGF-BB growth factor for achieving a quick method in wound healing. METHODS: In this study, Alginate sulfate hydrogel was made by photo-crosslinking method and methacrylate. Its toxicity was evaluated by MTT assay. Transforming growth factor was studied in releasing from synthesized alginate sulfate hydrogels and also, lack of toxicity was confirmed, and hydrogel was made with a recombinant human growth factor. Wounds were created with a diameter of 10 mm on the back of rats in order to check the wound healing. RESULTS: This study showed that alginate sulfate hydrogels-PDGF-BB were faster in wound healing than non-sulfate alginate hydrogels-PDGF-BB. Therefore, the controlled delivery of growth factor system can be a powerful idea for therapeutic applications for wound healing. CONCLUSION: Alginate sulfate hydrogel with recombinant growth factor 4 µg/cm2 (PDGF-BB) was very suitable for wound healing (Tab. 1, Fig. 3, Ref. 34).

Histologic analyses of different concentrations of TritonX-100 and Sodium dodecyl sulfate detergent in lung decellularization.

Pulmonary diseases cusecs a large portion of mortality in the world. There is no more cure for pulmonary diseases and many approaches are needed for finding ways to cure. Nowadays, implantation and drugs are only ways for curing those people who are facing with these diseases. Tissue engineering and regenerative medicine have been appeared as multidisciplinary field and also, they presents new therapeutic approaches for pulmonary diseases. One of these therapeutic approaches is decellularization which removes cellular but leaves intact important extracellular matrix (ECM) proteins and three-dimensional (3D) architecture and also, this approach has been studied for in-vitro and ex-vivo. In this study, we aimed to investigate a comparison of different concentrations of Triton X-100 and Sodium dodecyl sulfate detergents in lung decellularization in order to evaluate the effects of different concentrations and times of mentioned detergents on three dimensional and ECM proteins lung. Two detergents (Triton-X100 and Sodium dodecyl sulfat) were used with different concentrations for decellularizing rat lungs for maintaining of three-dimensional lung architecture and ECM protein compositions which have significant roles in differentiation and migration of stem cells. Results showed that SDS 0.05%, 0.1% and Triton-X100 0.1% could maintain 3D, elastin and collagen better than other concentrations in 24 and 48 h- decellularization. We concluded that these approaches can help to achieve three-dimensional architecture and extracellular matrix of lung with minimum destruction for next step such as recellularization and in-vivo study.

Isolation and identification of culturable halophilic bacteria with producing hydrolytic enzyme from Incheh Broun hypersaline wetland in Iran.

Incheh Broun hypersaline wetland is located near the border of Turkmenistan in thenorth of Iran. This wetland is notable because of salinity (280g/l) and alteration in pH range (2.8 to 6.8). Eastern part of wetland is affected by wastewater of iodine extraction factory.  Samples were taken from soil, water and salt. Totally, 400 bacterial strains were isolated of which 194 strains were Gram-positive bacilli, 184 strains were Gram-negative rod and 22 strains were Gram-positive cocci. According to phylogenetic analysis of 16S rRNA, selected strains were placed in three taxonomic phyla including Firmicutes, Actinobacteria and Gammaproteobacteria. Optimum growth was evaluated for salt and 22 strains were found to be moderate halophile and 33 strains were halotolerant. Production of lipase, amylase, gelatinase and protease was examined. Gram-positive bacilli were the main producers of hydrolytic enzymes. Gelatinase and protease were the most frequent enzymes. Gram-positive cocci were the main producers of lipase but they didn't produce amylase.

Cloning and expression of recombinant human platelet-derived growth factor-BB in Pichia Pink.

The PDGF-BB plays a key role in several pathogenesis diseases and it is believed to be an important mediator for wound healing. The recombinant human PDGF-BB is safe and effective to stimulate the healing of chronic, full thickness and lower extremity diabetic neurotrophic ulcers. In the present study, we attempted to produce a PDGF-BB growth factor and also, evaluate its functionality in cell proliferation in yeast host Pichia pink. Pichia pink yeast was used as a host for evaluation of the rhPDGF-BB expression. The coding sequence of PDGF-BB protein was synthesized after optimization and packed into the pGEM. Recombinant proteins were produced and purified. The construct of pPinkα-HC-pdgf was confirmed by sequence, the PDGF-BB protein was expressed and purified with using a nickel affinity chromatography column and then characterized by SDS-PAGE electrophoresis. The biological activity of PDGF-BB was estimated with using human fibroblast cell line. The measurement of protein concentration was determined by Bradford and human PDGF-BB ELISA kit. Purified rhPDGF-BB showed similar biological activity (as the standard PDGF-BB) and suggested that the recombinant protein has a successful protein expression (as well as considerable biological activity in P. pink host). The exact amount of recombinant PDGF-BB concentrations were measured by specific ELISA test which it was about 30 µg/ml. Our study suggested that efficiency of biological activity of PDGF-BB protein may be related to its conformational similarity with standard type and also, it practically may be important in wound healing and tissue regeneration.