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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21265086

RESUMO

SARS-CoV-2 genome surveillance projects provide a good measure of transmission and monitor the circulating SARS-CoV-2 variants at regional and global scales. Iran is one of the most affected countries still involved with the virus circulating in at least five significant disease waves, as of September 2021. Complete genome sequencing of 50 viral isolates in an early phase of outbreak in Iran, shed light on the origins and circulating lineages at that time. As part of a genomic surveillance program, we provided an additional 319 complete genomes from October 2020 onwards. The current study is the report of complete SARS-CoV-2 genome sequences of Iran in the March 2020-May 2021 time interval. We aimed to characterize the genetic diversity of SARS-CoV-2 in Iran over one year. Overall, 35 different lineages and 8 clades were detected. Temporal dynamics of the prominent SARS-CoV-2 clades/lineages circulating in Iran is comparable to the global perspective and introduces the 19A clade (B.4) dominating the first disease wave, followed by 20A (B.1.36), 20B (B.1.1.413), 20I (B.1.1.7) clades, dominating second, third and fourth disease waves, respectively. We observed a mixture of circulating 20A (B.1.36), 20B (B.1.1.413), 20I (B.1.1.7) clades in winter 2021, paralleled in a diminishing manner for 20A/20B and a growing rise for 20I, eventually prompting the 4th outbreak peak. Furthermore, our study provides evidence on the entry of the Delta variant in April 2021, leading to the 5th disease wave in summer 2021. Three lineages are highlighted as hallmarks of SARS-CoV-2 outbreak in Iran; B4, dominating early periods of the epidemic, B.1.1.413 (specific B.1.1 lineage carrying a combination of [D138Y-S477N-D614G] spike mutations) in October 2020-February 2021, and the co-occurrence of [I100T-L699I] spike mutations in half of B.1.1.7 sequences mediating the fourth peak. Continuous monthly monitoring of SARS-CoV-2 genome mutations led to the detection of 1577 distinct nucleotide mutations, in which the top recurrent mutations were D614G, P323L, R203K/G204R, 3037C>T, and 241C>T; the renowned combination of mutations in G and GH clades. The most frequent spike mutation is D614G followed by 13 other frequent mutations based on the prominent circulating lineages; B.1.1.7 (H69_V70del, Y144del, N501Y, A570D, P681H, T716I, S982A, D1118H, I100T, and L699I), B.1.1.413 (D138Y, S477N) and B.1.36 (I210del). In brief, mutation surveillance in this study provided a real-time comprehensive picture of the SARS-CoV-2 mutation profile in Iran, which is beneficial for evaluating the magnitude of the epidemic and assessment of vaccine and therapeutic efficiency in this population.

2.
Rep Biochem Mol Biol ; 9(1): 40-49, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32821750

RESUMO

BACKGROUND: KIT is a protooncogene that encodes for the KIT oncoprotein, which is a transmembrane tyrosine kinase growth factor receptor that holds a critical role in a variety of normal physiological and pathological processes including angiogenesis. KIT has been shown to be involved in tumorigenesis, contributing to the development of gastrointestinal carcinoma and leukemia. A link between KIT overexpression and breast cancer development has previously been reported. In the current study, we explored KIT gene expression and exonic copy number variants (CNV) and the relationship with angiogenesis (CD34) and the clinicopathological features of breast cancer. METHODS: MLPA technique was used to determine the CNV in 64 breast cancer tumor samples from patients diagnosed with primary sporadic breast cancer. Results were confirmed by quantitative PCR. Expression of KIT and CD34 was determined using immunohistochemistry (IHC). RESULTS: Our results show that 28.1% of the tumor samples from patients with primary sporadic breast cancer had CNV in the KIT gene. Among the breast tumor samples, 54.7% showed positive KIT expression. The expression of the CD34 angiogenesis marker was reported in 43.8% of the tumor samples as low, 42.2% as moderate and 14.1% as high. A significant correlation between increased CNV of KIT exons, a high level of angiogenesis (CD34) and increased tumor grade was observed (p< 0.05). CONCLUSION: A significant correlation between the KIT CNV and the angiogenesis marker was found. Examining KIT expression and CNV has the potential to function as a biomarker for tyrosine kinase inhibitor drugs in breast cancer.

3.
J Reprod Infertil ; 11(1): 33-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23926478

RESUMO

INTRODUCTION: Angiogenesis, growth of new blood vessels from pre-existing vessels, is a crucial physiological process for tissue regeneration. This state is also seen in pathological processes such as malignancies and endometriosis. Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis and vascular permeability which is known to play an important role in the development of endometriosis. The aim of this study was to investigate the relationship between +405 G>C VEGF polymorphism and endometriosis in an Iranian population. MATERIALS AND METHODS: The study population was comprised of 105 women with and 150 women without laparoscopic evidence of endometriosis. Genomic DNA from blood cells was extracted using salting out method. Genotype and allele frequency of +405 G>C polymorphism was compared between women with endometriosis and the controls using PCR-RFLP. Statistical analysis was performed using SPSS 13.0 software. Chi-squared test and odds ratio plus 95% confidence interval were determined. A p-value less than 0.05 was considered statistically significant. RESULTS: While the +405 VEGF genotype frequencies in the case group were 41.3% G/G, 46.2% C/G and %12.5 C/C, they were 32% GG, %53.3 GC and 14.7% CC in the control group. The distribution of three genotypes and allele frequencies of +405 G>C VEGF polymorphism between the case and control groups did not demonstrate any significant difference. CONCLUSION: In contrast to previous studies, no significant correlation was found between +405 G>C VEGF polymorphism and endometriosis. Since this was the first study in an Iranian population, further investigation with bigger sample sizes may be indicated to be able to generalize the findings.

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