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Showing 5 results for Zahri

Abdolmaleki A, Zahri S, Bezaatpour A,
Volume 71, Issue 1 (4 2013)
Abstract

Background: Salen metal complexes are used successfully in a wide range of asymmet-ric reactions and important in the pharmaceutical and industry. On the toxicity of salen vanadium oxide (VOsalen) on embryo and cell cultures, little information is available. In the present study, the toxic and teratogenic effects of VOsalen was evaluated against chicken embryos as a animal model and liver and fibroblast cell cultures which was derived from the embryo.
Methods: The VOsalen compound was synthesized. The compound solution was inject-ed in triplicate examination, in the air sac of the eggs, at third day of incubation. Treat-ed and control eggs, on day 19 of incubation opened and embryos were weighted, then mortality rate was recorded. The liver and fibroblast cell culture were treated by this and survival fraction was recorded.
Results: The survived fraction of the embryos depends on the compound concentration. In concentration of 300μM/egg, 36/32% of the embryos survived and the Lethal dose 50% (LD50) was 226/37 μM/egg. Morphological study of the treated embryos showed retarded growth, and skeletal staining showed the deletion of caudal vertebrate. The compound was inhibited liver and fibroblast cells growth with IC50 1047/25 and 1036/82μM respectively. The cytoplasm of treated cells became dense and their interco-nnections were loosed.
Conclusion: The VOsalen compound had low toxic effects against the embryos and the cultured cells at the concentrations. Significant cytotoxic effect was not observed in the treated cells. However the proliferative cells were affected significantly in comparison with the cells which their growth was stopped. The effect of VOsalen compound against replication of liver cells were lower than fibroblast cells.


Saeid Latifi-Navid, Shiva Mohammadi , Saber Zahri ,
Volume 71, Issue 11 (February 2014)
Abstract

Background: Helicobacter pylori has been classified as the class I carcinogenic agent by world health organization. Colonization of the human stomach with H. pylori is a risk factor for gastroduodenal diseases. The secreted vacA toxin is an important H. pylori virulence factor that causes multiple alterations in gastric epithelial cells and T cells. Several families of vacA alleles have been described, and H. pylori strains containing certain vacA types (s1 and m1) are associated with an increased risk of gastric disease, compared to strains containing other vacA types (s2 and m2). We examined the association between H. pylori vacA s alleles and gastroduodenal diseases in Iran. Methods: A total of 149 H. pylori strains were obtained from patients with gastritis, peptic ulcer, and gastric cancer referring to endoscopy units of several cities in Iran. Biopsy culture and DNA extraction were performed and the frequency of vacA s alleles was investigated by using PCR amplification. Linear regression and binary logistic regression models were used to analyze the association between vacA (vacuolating cytotoxin A) s alleles and gastroduodenal diseases. Results: There was no significant association between the frequency of vacA s alleles and gastroduodenal diseases (gastritis or peptic ulcer disease and gastric adenocarcinoma (P> 0.05)). Conclusion: It is proposed that the H. pylori vacA s1 genotype could not be considered as an important determinant of gastroduodenal diseases in Iranian population and probably if s1 allele is associated with other virulence alleles of this gene, it will cause diseases.
Seyedeh Zahra Bakhti, Saeid Latifi-Navid , Saber Zahri ,
Volume 72, Issue 9 (December 2014)
Abstract

Helicobacter pylori (H. pylori) is the causative agent in development of gastroduode-nal diseases, such as chronic atrophic gastritis, peptic ulcers, mucosa associated lym-phoid tissue (MALT) lymphoma, and gastric cancer. H. pylori has been associated with inflammation in cardia, showing the fact that infection with this bacterium could also be a risk factor for gastric cardia cancer. Gastric cancer is the fourth most common cancer worldwide. This is the second leading cause of cancer-related deaths, and ap-proximately 700,000 people succumb each year to gastric adenocarcinoma. It has been estimated that 69% of the Iranian population currently harbor H. pylori infection. The prevalence of duodenal ulcer and gastric cancer is high in Iranian populations. However, this has been largely influenced by geographic and/or ethnic origin. Epidemi-ology studies have shown that host, environmental, and bacterial factors determine the outcome of H. pylori infection. The bacterium contains allelic diversity and high genet-ic variability into core- and virulence-genes and that this diversity is geographically and ethnically structured. The genetic diversity within H. pylori is greater than within most other bacteria, and its diversity is more than 50-fold higher than that of human DNA. The maintenance of high diversification makes this bacterium to cope with particular challenges in individual hosts. It has been reported that the recombination contributed to the creation of new genes and gene family. Furthermore, the microevolution in cagA and vacA genes is a common event, leading to a change in the virulence phenotype. These factors contribute to the bacterial survival in acidic conditions in stomach and protect it from host immune system, causing tissue damage and clinical disease. In this review article, we discussed the correlation between H. pylori virulence factors and clin-ical outcomes, microevolution of H. pylori virulence genes in a single host, microevolu-tion of H. pylori during primary infection and progression of atrophic gastritis to ade-nocarcinoma, and H. pylori infection status in Iran. Finally, we put forward the hy-pothesis that if the pattern of nucleotide sequence evolution shifts from recombination (r) to mutation (m) and the r/m ratio is reduced, bacterial pathogenicity may be re-duced while maintaining the bacterial life. However, this hypothesis should be further studied with future experiments.
Esmat Abdi , Saeid Latifi-Navid , Hamid Latifi-Navid , Saber Zahri, Abbas Yazdanbod ,
Volume 76, Issue 6 (September 2018)
Abstract

Gastric cancer (GC) is the second leading cause of cancer-related deaths worldwide. It has been proposed that the specific genotypes of Helicobacter pylori (H. pylori) are the causative agents in the development of gastroduodenal diseases, such as chronic atrophic gastritis, peptic ulcerations, and GC. However, disease progression to GC occurs in only a small proportion of infected patients. Recently, we identified a novel polymorphic site in the 3ʹ-end region of H. pylori vacA gene. The vacA c1 genotype increased the risk of GC. This association was independent of and larger than the associations of the m-, i-, and d-type of vacA or cagA status with GC. Therefore, treatment of H. pylori infection may be an effective way to prevent GC. Expression of cytokines and their associations with inflammatory responses has been shown. Several cytokine polymorphisms, such as IL-1B, IL-8, IL-10, and TNF-α have been considered as risk factors for GC. It has been shown that the interaction of bacterial genotypes and host factors plays an essential role in developing GC. Several altered molecular pathways are involved in the pathogenesis of GC. Micro-RNAs are small, non-coding RNAs of 18-25 nucleotides in length that regulate the expression of target mRNAs. Expression pattern of cancer cells is different compared with the normal cells. Micro-RNAs plays a critical role in apoptosis and classified in two groups: pro- and anti-apoptotic agents. Recent studies have confirmed the oncogenic or tumor suppression role of micro-RNAs in cancer cells. They play a significant role in the GC cell physiology and tumor progression, by translational suppression of target genes. These small RNAs have therefore emerged as a new type of GC biomarker with immeasurable clinical potential. Generally, a variety of micro-RNAs involved in different stages of cancer, including tumorigenesis, angiogenesis, and metastasis. Considering to this issue more than 50% of cancers can be cured, if they were diagnosed in the early stages. Hence, identifying the biomarkers of GC could play an important role in prevention, early diagnosis and rapid treatment of patients. In this review article, we have reviewed the latest findings about bacterial and tissue biomarkers of GC

Arash Abdolmaleki, Mohammad-Bagher Ghayour, Saber Zahri, Asadollah Asadi , Morteza Behnam-Rassouli ,
Volume 77, Issue 2 (May 2019)
Abstract

Background: Tissue engineering is a developing multidisciplinary and interdisciplinary field involving the use of bioartificial implants for tissue remodeling with the target for repair and enhancing tissue or organ function. Acellular nerve has been used in experimental models as a peripheral nerve substitute. The purpose of the present study was to evaluate the mechanical and histological characteristics of acellular nerve scaffolds compared to the fresh nerve for application in environmental nerve repair.
Methods: This experimental study was conducted in Ferdowsi University of Mashhad Regeneration Research Laboratory, Mashhad, Iran, from May 2017 to October 2018. In this study for preparing the scaffold. The rats were sacrificed by intraperitoneal anesthesia with 10 % Chloral Hydrate solution. Then sciatic nerve fragments of the rats were removed above the nerve branching site and after cleansing of the tissues were decellularized by Sondell method, briefly nerves were treated with a series of detergent baths consisting of distilled water for 8 h, Triton X-100 for 12 h, and sodium deoxycholate for 24 hours according to the Sondell protocol. All acellularization steps were performed at room temperature. Then decellularized scaffolds were evaluated histologically and mechanically.
Results: The results of tissue evaluations showed that decellularization of scaffolds were done completely, this was demonstrated by hematoxylin and eosin staining and DAPI staining. Also the specialized tissue evaluations by picro-fuchsin staining and evaluation the scaffolds by scanning electron microscopy (SEM) micrographs showed that the collagen and elastin strands are relatively preserved in the extracellular matrix in comparison with control groups. As well as mechanical examination of scaffolds in tensile test showed that extracellular matrix of scaffolds was relatively preserved the main components of tissue compared to control group and scaffolds have good mechanical resistance quality for use in tissue engineering.
Conclusion: The results of the present study showed that decellularized scaffolds that prepared with Sondell decellularization method by preserving the main components of the tissue can be a good platform for investigating cellular behaviors.


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