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51.
CRC-associated P53 mutations have not been studied extensively in non-Western countries at relatively low CRC risk. We examined, for the first time, 196 paraffin-embedded CRC cases from Northern Iran for mutations in P53 exons 5-8 using PCR-direct sequencing. P53 status and mutation site/type were correlated with nuclear protein accumulation, clinicopathologic variables and data on K-ras mutations and high-level microsatellite instability (MSI-H). We detected 96 P53 mutations in 87 (44.4%) cases and protein accumulation in 84 cases (42.8%). P53 mutations correlated directly with stage and inversely with MSI-H. Distal CRCs were more frequently mutated at major CpG hotspot codons [248 (8/66, 12.1%), 175 (7/66, 10.6%), and 245 (7/66, 10.6%)], while in proximal tumors codon 213, emerged as most frequently mutated (5/28, 17.9% vs. 3/66, 4.5%, P = 0.048). Transitions at CpGs, the most common mutation type, were more frequent in non-mucinous (25% vs. 10.4% in mucinous, P = 0.032), and distal CRC (27% vs. 12.5% in proximal, P = 0.02), and correlated with K-ras transversions. Transitions at non-CpGs, second most common P53 mutation, were more frequent in proximal tumors (15.6% vs. 4.7% in distal, P = 0.01), and correlated with K-ras transitions and MSI-H. Overall frequency and types of mutations and correlations with P53 accumulation, stage and MSI-H were as reported for non-Iranian patients. However P53 mutation site/type and correlations between P53 and K-ras mutation types differed between proximal and distal CRC. The codon 213 P53 mutation that recurred in proximal CRC was previously reported as frequent in esophageal cancer from Northern Iran.  相似文献   
52.
Since the building of coral reefs results from the association of corals and zooxanthellae, their intracellular algal symbionts, genetic markers for both organisms are essential for studying the contribution of their respective dispersal to the resilience of endangered reef ecosystems. Very few microsatellites have been obtained in corals thus far. Here we report the successful cloning of six polymorphic microsatellites (allele number: 5–15) from Pocillopora verrucosa, P. meandrina and P. damicornis. Four of them amplified coral, and two amplified zooxanthella DNA.  相似文献   
53.
Zearalenone (ZON) is a nonsteroidal estrogenic mycotoxin produced by plant-pathogenic species of Fusarium. As a consequence of infection with Fusarium culmorum and Fusarium graminearum, ZON can be found in cereals and derived food products. Since ZON is suspected to be a cause of human disease, including premature puberty syndrome, as well as hyperestrogenism in farm animals, several countries have established monitoring programs and guidelines for ZON levels in grain intended for human consumption and animal feed. We developed a low-cost method for monitoring ZON contamination in grain based on a sensitive yeast bioassay. The indicator Saccharomyces cerevisiae strain YZRM7 is unable to grow unless an engineered pyrimidine biosynthetic gene is activated by the expressed human estrogen receptor in the presence of exogenous estrogenic substances. Deletion of the genes encoding ATP-binding cassette (ABC) transporters Pdr5p and Snq2p increases net ZON uptake synergistically. Less than 1 μg of ZON per liter of medium is sufficient to allow growth of the indicator strain. To prevent interference with pyrimidines potentially present in biological samples, we also disrupted the genes FUR1 and URK1, blocking the pyrimidine salvage pathway. The bioassay strain YZRM7 allows qualitative detection and quantification of total estrogenic activity in cereal extracts without requiring further cleanup steps. Its high sensitivity makes this assay suitable for low-cost monitoring of contamination of maize and small grain cereals with estrogenic Fusarium mycotxins.  相似文献   
54.
Isolation of a novel stable peptide from cultivated Raphanus sativus with peroxidase activity has been achieved using zinc ion precipitation followed by aqueous two phase extraction with a polyethylene glycol (PEG)/phosphate system. The best result was achieved with PEG 600/phosphate (28.8/13% w/v) which extracted 96.15% of total enzyme activity. The peptide has a molecular weight of 5.85 kD as determined by HPLC size exclusion method with an optimized pH of 6.  相似文献   
55.
Calprotectin is member of the S-100 protein family with a wide plethora of intra-and extracellular functions. Anticancer activities, antimicrobial effects and being a qualified disease marker are among the compelling features of this protein to be used as a pharmaceutical agent. However, there are several impediments to applications of protein pharmaceuticals including: proteolytic degradation, short circulating half-life, low solubility and immunogenicity. Pegylation is a common bioconjugation polymer capable of overcoming these drawbacks. Recombinant expression and purification of calprotectin along with its pegylation would result in enhanced pharmaco-dynamic and pharmacokinetic properties. Our florescence spectroscopy and far Ultraviolet-optical density results indicate that pegylation altered the physical and structural properties of the calprotectin to become in a more stable and functionally active state. Due to enhanced pharmacodynamic and pharmacokinetic properties of the calprotectin via pegylation, this study would pave the way for better in vitro and in vivo validations of calprotectin applications in medical practice.  相似文献   
56.
Hemagglutinin–neuraminidase (HN) protein besides its mediation in viral pathogenesis, is composed of various antigenic sites which stimulate production of host’s antibodies. Thus, application of this protein in serological tests and vaccination plays a major role in biosecurity and control programs. In the present study, we designed a recombinant HN protein containing different neutralizing antigenic sites with velogenic patterns, and sub-cloned it into pET-43.1a+ expression vector. The expression of NusA-HN recombinant protein was induced. Affinity chromatography protein purification using HisPur? Ni–NTA was then conducted. Moreover, we performed western-blot technique using HRP-conjugated Anti His-Tag. Results revealed that following induction of recombinant protein, two distinct bands of HN-61 kDa and NusA-63 kDa were purified and identified by western-blotting. We recommend further analysis should be carried out to determine the functional role of this recombinant protein in enzyme-linked immunosorbent assays for Newcastle disease diagnosis. This HN protein containing multi neutralizing antigenic sites might also be applicable in vaccination programs to increase vaccines potency.  相似文献   
57.
Acute respiratory distress syndrome (ARDS) is the most common cause of death in COVID-19 patients. The cytokine storm is the main driver of the severity and magnitude of ARDS. Placenta-derived decidua stromal cells (DSCs) have a stronger immunosuppressive effect than other sources of mesenchymal stromal cells. Safety and efficacy study included 10 patients with a median age of 50 (range 14–68) years with COVID-19-induced ARDS. DSCs were administered 1–2 times at a dose of 1 × 106/kg. End points were safety and efficacy by survival, oxygenation and effects on levels of cytokines. Oxygenation levels increased from a median of 80.5% (range 69–88) to 95% (range 78–99) (p = 0.012), and pulmonary infiltrates disappeared in all patients. Levels of IL-6 decreased from a median of 69.3 (range 35.0–253.4) to 11 (range 4.0–38.3) pg/ml (p = 0.018), and CRP decreased from 69 (range 5–169) to 6 (range 2–31) mg/ml (p = 0.028). Two patients died, one of a myocardial infarction and the other of multiple organ failure, diagnosed before the DSC therapy. The other patients recovered and left the intensive care unit (ICU) within a median of 6 (range 3–12) days. DSC therapy is safe and capable of improving oxygenation, decreasing inflammatory cytokine level and clearing pulmonary infiltrates in patients with COVID-19.  相似文献   
58.
Abnormal expression of various microRNAs (miRNAs), as regulators of biological signaling pathways, has a strong association with cancer resistance to chemotherapy and radiotherapy. The let-7 family of miRNAs as tumor suppressors have shown to be downregulated in different types of human malignancies including colorectal cancer (CRC). However, the biological function of let-7 members in the processes of resistance to radiation in CRC has not yet been completely elucidated. Insulin-like growth factor 1 receptor (IGF-1R) signaling pathway is amplified in CRC and leads to its progression, development, and also radiation resistance. So, it seems like an attractive target for anticancer therapy. In this study, by using bioinformatics analysis, it has been revealed that IGF-1R is a direct target of the let-7e member. Consistent with this, we identified that increased levels of let-7e in CRC cells reduced IGF-1R protein level and subsequently its downstream signaling pathways, which resulted in the G1 cell cycle arrest and a significant reduction in the proliferation, survival and also resistance to radiation of CRC cells. Altogether, these results suggested that let-7e by targeting the IGF-1R signaling pathway might serve as therapeutics in anticancer therapy.  相似文献   
59.
Journal of Plant Growth Regulation - The salinization of agriculture soils over the globe has become one of the most devastating stresses and is significantly limiting cultivated land area, and...  相似文献   
60.
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