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Vitrification is considered a viable method for cryopreservation of ovarian tissue and selection of methods that minimize follicular damage is important. The objective of the present study was to evaluate the effects of two vitrification methods on ovarian tissue morphology, preantral follicles survival rate during in vitro culture, and relative expression of genes associated with oocyte maturation and cumulus expansion. Ovaries from 12-day-old mice were vitrified in media containing ethylene glycol, dimethyl sulphoxide, and sucrose. Before plunging in liquid nitrogen, ovaries were first loaded into an acupuncture needle (needle immersion vitrification [NIV]) or placed on a cold steel surface for 10 to 20 seconds (solid surface vitrification [SSV]). The integrity of the ovarian tissue was well-preserved after vitrification and was similar controls. Follicle viability in the SSV group was lower (P < 0.05) than in the control group after 6 days of culture and the NIV group after 10 day of culture. Follicle viability after 12 day of culture was 92.8%, 82.1%, and 58.4% in control, NIV, and SSV groups, respectively. Bmp15, Gdf9, BmprII, Alk6, Alk5, Has2, and Ptgs2 gene expression patterns were similar among groups. However, the level of gene expression in the vitrification groups during Days 6 to 10 were higher compared with the control group. In conclusion, ovarian tissue morphologic integrity was well-preserved, regardless of the vitrification method. Vitrification using the needle immersion method resulted in greater follicular survival after 12 day of culture than the SSV method. Gene expression patterns during culture did not seem to explain the reduced survival rate observed in the solid surface group. 相似文献
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Over-accumulation of nuclear IGF-1 receptor in tumor cells requires elevated expression of the receptor and the SUMO-conjugating enzyme Ubc9 总被引:1,自引:0,他引:1
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Bita Naseri 《Journal of Phytopathology》2013,161(6):397-404
During two growing seasons (2008 and 2009), the associations of Rhizoctonia root rot (RRR) with a number of soil properties were determined at different growth stages in 122 commercial bean fields in Zanjan, Iran. Mean RRR incidence at a level of 4–25% sand content was lower than that at 45–65% level. Damage by fly puparia had no significant effect on RRR incidence and occurrence. A greater RRR incidence was detected in field soils treated with fungicides compared with non‐treated soils. A lower RRR incidence was associated with the highest level of soil organic matter (1.2–1.8) compared with the lowest level, 0.4–0.8. The highest RRR incidence corresponded with no rhizobial nodulation compared with highly nodulated bean roots. RRR incidence was negatively correlated with soil silt and organic matter content at R6–7 and R9 growth stages. RRR‐affected fields were recognized with a greater soil pH (V3) and sand content (R9), and a lower silt (R9) and organic matter content (R6–7 and R9) in comparison with RRR‐free fields. Loadings and linear regressions between RRR incidence and principal component scores indicated that the most effective soil characteristic linked to the disease was silt at V3, sand at R6–7 and organic matter at R9 stage. This new epidemiological information extends our knowledge of the bean–RRR–soil interaction on a regional basis. 相似文献
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Hasan Alniss Bita Zamiri Melisa Khalaj Christopher E. Pearson Robert B. Macgregor 《Biochemical and biophysical research communications》2018,495(4):2410-2417
Background
An expansion of the hexanucleotide repeat (GGGGCC)n·(GGCCCC)n in the C9orf72 promoter has been shown to be the cause of Amyotrophic lateral sclerosis and frontotemporal dementia (ALS-FTD). The C9orf72 repeat can form four-stranded structures; the cationic porphyrin (TMPyP4) binds and distorts these structures.Methods
Isothermal titration calorimetry (ITC), and circular dichroism (CD) were used to study the binding of TMPyP4 to the C-rich and G-rich DNA and RNA oligos containing the hexanucleotide repeat at pH 7.5 and 0.1?M?K+.Results
The CD spectra of G-rich DNA and RNA TMPyP4 complexes showed features of antiparallel and parallel G-quadruplexes, respectively. The shoulder at 260?nm in the CD spectrum becomes more intense upon formation of complexes between TMPyP4 and the C-rich DNA. The peak at 290?nm becomes more intense in the c-rich RNA molecules, suggesting induction of an i-motif structure. The ITC data showed that TMPyP4 binds at two independent sites for all DNA and RNA molecules.Conclusions
For DNA, the data are consistent with TMPyP4 stacking on the terminal tetrads and intercalation. For RNA, the thermodynamics of the two binding modes are consistent with groove binding and intercalation. In both cases, intercalation is the weaker binding mode. These findings are considered with respect to the structural differences of the folded DNA and RNA molecules and the energetics of the processes that drive site-specific recognition by TMPyP4; these data will be helpful in efforts to optimize the specificity and affinity of the binding of porphyrin-like molecules. 相似文献26.
Bita Zamiri Mila Mirceta Rashid Abu-Ghazalah Marc S. Wold Christopher E. Pearson Robert B. Macgregor 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(6):1482-1491
Background
Expansion of the C9orf72 hexanucleotide repeat (GGGGCC)n·(GGCCCC)n is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Both strands of the C9orf72 repeat have been shown to form unusual DNA and RNA structures that are thought to be involved in mutagenesis and/or pathogenesis. We previously showed that the C-rich DNA strands from the C9orf72 repeat can form four-stranded quadruplexes at neutral pH. The cytosine residues become protonated under slightly acidic pH (pH?4.5–6.2), facilitating the formation of intercalated i-motif structures.Methods
Using CD spectroscopy, UV melting, and gel electrophoresis, we demonstrate a pH-induced structural transition of the C-rich DNA strand of the C9orf72 repeat at pHs reported to exist in living cells under stress, including during neurodegeneration and cancer.Results
We show that the repeats with lengths of 4, 6, and 8?units, form intercalated quadruplex i-motifs at low pH (pH?<?5) and monomolecular hairpins and monomolecular quadruplexes under neutral-basic conditions (pH?≥?8). Furthermore, we show that the human replication protein A (RPA) binds to the G-rich and C-rich DNA strands under acidic conditions, suggesting that it can bind to i-motif structures.Conclusions
In the proper sequence context, i-motif structures can form at pH values found in some cells in vivo.General significance
DNA conformational plasticity exists over broad range of solution conditions. 相似文献27.
Sahar Irankhah Ahya Abdi Ali Mohammad Reza Soudi Sara Gharavi Bita Ayati 《World journal of microbiology & biotechnology》2018,34(11):164
In this study, the efficiency improvement of three moving bed biofilm reactors (MBBRs) was investigated by inoculation of activated sludge cells (R1), mixed culture of eight strong phenol-degrading bacteria consisted of Pseudomonas spp. and Acinetobacter spp. (R2) and the combination of both (R3). Biofilm formation ability of eight bacteria was assessed initially using different methods and media. Maximum degradation of phenol, COD, biomass growth and also changes in organic loading shock were used as parameters to measure the performance of reactors. According to the results, all eight strains were determined as enhanced biofilm forming bacteria (EBFB). Under optimum operating conditions, more than 90% of initial COD load of 2795 mg L?1 was reduced at 24 HRT in R3 while this reduction efficiency was observed in concentrations of 1290 mg L?1 and 1935 mg L?1, in R1 and R2, respectively. When encountering phenol loading shock—twice greater than optimum amount-R1, R2 and R3 managed to return to the steady-state condition within 32, 24 and 18 days, respectively. SEM microscopy and biomass growth measurements confirmed the contribution of more cells to biofilm formation in R3 followed by R2. Additionally, established biofilm in R3 was more resistant to phenol loading shock which can be attributed to the enhancer role of EBFB strains in this reactor. It has been demonstrated that the bacteria with both biofilm-forming and contaminant-degrading abilities are not only able to promote the immobilization of other favorable activated sludge cells in biofilm structure, but also cooperate in contaminant degradation which all consequently lead to improvement of treatment efficiency. 相似文献
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Gene polymorphisms of macrophage migration inhibitory factor affect susceptibility to chronic hepatitis B virus infection in an Iranian cohort 下载免费PDF全文
Bita Moudi Zahra Heidari Hamidreza Mahmoudzadeh‐Sagheb Mohammad Hashemi 《Microbiology and immunology》2016,60(6):390-396
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Simin Najjar Bita Asgari Amir Hossein Mohammadi 《Archives Of Phytopathology And Plant Protection》2017,50(7-8):349-360
The aim of the present study was to isolate and identify Aspergillus species associated with saffron plants in the city of Birjand (South Khorasan Province, Iran) as well as to assess their aflatoxin B1 production. Sampling was performed during 2013–2014 crop season. Aspergillus species were isolated and purified using general and specific culture media. Growth rates and macroscopic and microscopic characteristics of the isolates were determined using yeast extract, Czapek yeast extract, malt extract and creatine sucrose agar media at 25 and 37 °C. DNA was extracted by the modified CTAB method and beta-tubulin, calmodulin and internal transcribed spacer genes were amplified and sequenced. Phylogenetic position of the isolates was determined against other Aspergillus species. Thin layer chromatography was used to investigate the production of aflatoxin B1 by Aspergillus isolates. Based on the morphological characteristics, shape and colour of the colonies, and sequencing results, the isolates belonged to Aspergillus terreus, A. flavus, A. flavipes and A. niger species. Only A. flavus isolates were aflatoxin B1 producers. We concluded that the soil of the studied saffron fields contained several species of Aspergillus, with A. flavus significantly affecting crop production through contamination of the crop by aflatoxin. 相似文献