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Durum wheat is capable of accumulating cadmium, a toxic heavy metal, in the grain at levels that have been deemed unsafe for human consumption. Previous studies have identified genetic variation as well as markers associated with Cd accumulation in durum wheat, which can be exploited to develop low Cd cultivars. Because the phenotyping for Cd content is very expensive, KASP markers were developed from molecular markers associated with grain Cd and tested for their usefulness for marker-assisted breeding. A total of 1278 unique genotypes from preliminary and advanced yield trials grown at multiple locations for 2 years were evaluated for grain Cd as well as screened for markers associated with Cd uptake. One marker on chromosome 5B was polymorphic in all crosses between high and low Cd parents and had r2 values ranging from 0.38 to 0.85. Two other markers on the same chromosome predicted similar levels of variation in many trials; however, they were not polymorphic in all populations. The KASP markers accurately predicted up to 97% of the lines for Cd phenotype in different trials. This study identified two markers, Cad-5B and Ex_c1343_2570756, with an average prediction accuracy of 84–88%. These markers could be useful for marker-assisted selection for low grain Cd in durum wheat.  相似文献   
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This study aimed to assess genotoxicity in wild plants grown in Jordan as a pollution bioindicator. Comet assay was used to evaluate the level of DNA damage in plants collected from different areas in Jordan. Significant differences in plant DNA damage index and frequency were observed among sites of collection. Results show that plants collected from Aqaba back road and Ghour Assaal had significantly higher damage values. In contrast, plants collected from Wadi Rum, Al Naqab Heights, Swaimeh/Deadsea and Alshoneh Aljanobyeh showed low levels of DNA damage. A similar trend was observed for lipid peroxidation rates. Furthermore, heavy metal analysis showed that plants collected from Aqaba back road and Aqaba airport had the highest Al, Cr, Fe, Cu, Zn, Cd and Pb contents. A significant correlation was observed between DNA Damage Index, DNA Damage Frequency, lipid peroxidation rate, soil Cu, Cd and Pb biomarkers, indicating that heavy metals pollution is a major source for genotoxicity in these plant species. Finally, our results approved the feasibility of using plants and Comet assay system as a diagnostic tool for pollution in any environment adversely affected by different pollution sources.  相似文献   
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Cichorium pumilum, a member of Asteraceae, is widely used as a traditional medicinal herb. An efficient protocol for callus formation and whole plant propagation has been developed. Callus cultures were induced from leaf explants on Murashige and Skoog (MS) medium supplemented with 1.5?mg?l?1 6-Benzyladenine (BA) and 0.5?mg?l?1 Naphthalene acetic acid (NAA). Maximum numbers of shoots were obtained from calli transferred to shoot regeneration medium containing MS basal medium with 1.5?mg?l?1 BA or Kinetin (Kin). The shoots were effectively rooted on MS medium supplemented with different concentrations of Indole-3-butyric acid. In the present study, the antibacterial activity of C. pumilum extracts was assayed in vitro by agar disc diffusion and agar well diffusion methods against 10 different bacterial species. The results showed effect on the growth of 50 and 70% of the tested bacterial species using methanol and ethanol extracts respectively. Klebsiella pneumoniae was susceptible to the ethanolic and methanolic extracts of wild plants and in vitro tissues, whereas Enterococcus faecalis was resistant to all the extracts. This study verified that the methanol extracts have strong antioxidant activities with high levels of phenolic compounds. The antioxidant activity and total phenol content of callus cultures and in vitro plantlets were lower than those of the wild plants. The results obtained confirm the therapeutic potency of Cichorium used in the traditional medicine, in addition, the efficient in vitro production system developed in this study provide sterile and consistent tissues for the investigation of phytochemical and pharmacological effects and germplasm conservation of C. pumilum.  相似文献   
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Objective

Stripping of the membranes is an established and widely utilized obstetric procedure associated with higher spontaneous vaginal delivery rates, reduced need for formal induction of labor and a lower likelihood of post-term pregnancy. Due to the theoretical concern of bacterial seeding during the procedure many practitioners choose not to sweep the membranes in Group B Streptococcus (GBS) colonized patients. We conducted ‘the STRIP-G study’ in order to determine whether maternal and neonatal outcomes are affected by GBS carrier status in women undergoing membrane stripping.

Study design

We conducted a prospective study in a tertiary referral center, comparing maternal and neonatal outcomes following membrane stripping among GBS-positive, GBS-negative, and GBS-unknown patients. We compared the incidence of composite adverse neonatal outcomes (primary outcome) among the three study groups, while secondary outcome measure was composite adverse maternal outcomes.

Results

A total of 542 women were included in the study, of which 135 were GBS-positive, 361 GBS-negative, and 46 GBS-unknown status. Demographic, obstetric, and intra-partum characteristics were similar for all groups. Adverse neonatal outcomes were observed in 8 (5.9%), 31 (8.6%), and 2 (4.3%) in the GBS-positive, GBS-negative, and unknown groups, respectively (P = 0.530), (Odds Ratio between GBS-Positive vs. GBS-Negative groups 0.67 (95%, CI = 0.30–1.50)); while composite adverse maternal outcomes occurred in 9 (6.66%), 31 (8.59%), and 5 (10.87%) in the GBS-positive, GBS-negative, and unknown groups, respectively (P = 0.617).

Conclusions

Antepartum membrane stripping in GBS carriers appears to be a safe obstetrical procedure that does not adversely affect maternal or neonatal outcomes.  相似文献   
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The pollution of raw surface and underground water with pharmaceutical compounds has an impact on increasing the resistance of pathogenic microorganisms. Environmental challenges include investigating a novel and cost-effective therapeutic approach for the bactericidal treatment of water supplies. Ethyl acetate extracts from three marine algae (Caulerpa racemosa, Codium fragile, and Cystoseira myrica) obtained from the Red Sea (Hurghada, Egypt) were used for the green synthesis of TiO2 nanoparticles (TiO2-NPs). A highly crystalline nanoparticle structure with a stable tetragonal anatase structure was obtained; the mean concentrations were 2.43 to 6.09?×?108 NPs/mL and the average particle size was 125–131 nm. In ultrapure water, the TiO2-NPs were confirmed to be a stable solution following zeta potential analysis. UV light (λ?=?350 nm) for 2 h was used to activate the TiO2-NPs before the antibacterial activity tests. The application of UV-activated TiO2-NPs for 4 h treatments demonstrated promising bactericidal activity, with a 73.08% reduction in Salmonella typhi and a 91.51% reduction in Enterobacter ludwigii. Antibiofilm activities against the reference strains Salmonella typhi NCTC 12023/ATTC and Morganella morganii ATCC25829 and the bacterial isolates Klebsiella pneumoniae, Enterobacter ludwigii, and Enterococcus faecium were tested. The TiO2-NPs were nontoxic against the human normal cell line RPE1. Regarding the treatment of total and fecal coliform, in addition to fecal streptococci, in raw surface and underground water, the UV-activated TiO2-NPs prepared from the ethyl acetate extracts of Caulerpa racemosa showed high applicability. The present study offered insights into the nature and development of nontoxic and green TiO2-NP formulations for use as modern antibacterial alternatives against coliforms in aquatic systems.

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Recent findings suggested several allosteric pockets on human aromatase that could be utilised for the development of new modulators able to inhibit this enzyme in a new mechanism. Herein, we applied an integrated in-silico-based approach supported by in-vitro enzyme-based and cell-based validation assays to select the best leads able to target these allosteric binding sites from a small library of plant-derived natural products. Chrysin, apigenin, and resveratrol were found to be the best inhibitors targeting the enzyme’s substrate access channel and were able to produce a competitive inhibition with IC50 values ranged from 1.7 to 15.8 µM. Moreover, they showed a more potent antiproliferative effect against ER+ (MCF-7) than ER- one (MDA-MB-231) cell lines. On the other hand, both pomiferin and berberine were the best hits for the enzyme’s haem-proximal cavity producing a non-competitive inhibition (IC50 15.1 and 21.4 µM, respectively) and showed selective antiproliferative activity towards MCF-7 cell lines.  相似文献   
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Cholangiocellular carcinoma (CCA) of the liver was the target of more interest, recently, due mainly to its increased incidence and possible association to new environmental factors. Somatic mitochondrial DNA (mtDNA) mutations have been found in several cancers. Some of these malignancies contain changes of mtDNA, which are not or, very rarely, found in the mtDNA databases. In terms of evolutionary genetics and oncology, these data are extremely interesting and may be considered a sign of poor fitness, which may conduct in some way to different cellular processes, including carcinogenesis. MitoChip analysis is a strong tool for investigations in experimental oncology and was carried out on three CCA cell lines (HuCCT1, Huh-28 and OZ) with different outcome in human and a Papova-immortalized normal hepatocyte cell line (THLE-3). Real time quantitative PCR, western blot analysis, transmission electron microscopy, confocal laser microscopy, and metabolic assays including L-Lactate and NAD+/NADH assays were meticulously used to identify mtDNA copy number, oxidative phosphorylation (OXPHOS) content, ultrastructural morphology, mitochondrial membrane potential (ΔΨm), and differential composition of metabolites, respectively. Among 102 mtDNA changes observed in the CCA cell lines, 28 were non-synonymous coding region alterations resulting in an amino acid change. Thirty-eight were synonymous and 30 involved ribosomal RNA (rRNA) and transfer RNA (tRNA) regions. We found three new heteroplasmic mutations in two CCA cell lines (HuCCT1 and Huh-28). Interestingly, mtDNA copy number was decreased in all three CCA cell lines, while complexes I and III were decreased with depolarization of mitochondria. L-Lactate and NAD+/NADH assays were increased in all three CCA cell lines. MtDNA alterations seem to be a common event in CCA. This is the first study using MitoChip analysis with comprehensive metabolic studies in CCA cell lines potentially creating a platform for future studies on the interactions between normal and neoplastic cells.  相似文献   
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Low dose methotrexate is the cornerstone for the treatment of rheumatoid arthritis. One of its major drawbacks is hepatotoxicity, resulting in poor compliance of therapy. Dissatisfied arthritis patients are likely to seek the option of complementary and alternative medicine such as bee venom. The combination of natural products with modern medicine poses the possibility of potential interaction between the two groups and needs investigation. The present study was aimed to investigate the modulatory effect of bee venom acupuncture on efficacy, toxicity, and pharmacokinetics and tissue disposition of methotrexate. Complete Freund''s adjuvant induced arthritic rats were treated for 3 weeks with methotrexate and/or bee venom. Arthritic score, ankle diameter, paw volume and tissue expression of NF-κB and TNF-α were determined to assess anti-arthritic effects, while anti-nociceptive effects were assessed by gait score and thermal hyperalgesia. Methotrexate toxicity was assessed by measuring serum TNF-α, liver enzymes and expression of NF-κB in liver. Combination therapy of bee venom with methotrexate significantly improved arthritic parameters and analgesic effect as compared to methotrexate alone. Bee venom ameliorated serum TNF-α and liver enzymes elevations as well as over expression of NF-κB in liver induced by methotrexate. Histological examination supported the results. And for the first time bee venom acupuncture was approved to increase methotrexate bioavailability with a significant decrease in its elimination. Conclusion: bee venom potentiates the anti-arthritic effects of methotrexate, possibly by increasing its bioavailability. Also, it provides a potent anti-nociceptive effect. Furthermore, bee venom protects against methotrexate induced hepatotoxicity mostly due to its inhibitory effect on TNF-α and NF-κB.  相似文献   
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