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991.
Ahmadpour Sajjad Khodadust Fatemeh Hormati Ahmad Eivaziatashbeik Karim 《International journal of peptide research and therapeutics》2021,27(1):503-525
International Journal of Peptide Research and Therapeutics - Gastric cancer (GC) is still ranked fourth among malignant cancers and remained as the second leading cause of cancer related death.... 相似文献
992.
Karim Zuhra Catarina S. Tomé Elena Forte João B. Vicente Alessandro Giuffrè 《BBA》2021,1862(2):148338
Sulfane sulfur species comprise a variety of biologically relevant hydrogen sulfide (H2S)-derived species, including per- and poly-sulfidated low molecular weight compounds and proteins. A growing body of evidence suggests that H2S, currently recognized as a key signaling molecule in human physiology and pathophysiology, plays an important role in cancer biology by modulating cell bioenergetics and contributing to metabolic reprogramming. This is accomplished through functional modulation of target proteins via H2S binding to heme iron centers or H2S-mediated reversible per- or poly-sulfidation of specific cysteine residues. Since sulfane sulfur species are increasingly viewed not only as a major source of H2S but also as key mediators of some of the biological effects commonly attributed to H2S, the multifaceted role of these species in cancer biology is reviewed here with reference to H2S, focusing on their metabolism, signaling function, impact on cell bioenergetics and anti-tumoral properties. 相似文献
993.
994.
Mohammad-Nazir Menbari Karim Rahimi Abbas Ahmadi Samira Mohammadi-Yeganeh Anvar Elyasi Nikoo Darvishi Vahedeh Hosseini Mohammad Abdi 《Journal of cellular physiology》2020,235(3):2631-2642
Triple negative breast cancer (TNBC) is a heterogeneous subclass of breast cancer (BC) distinguished by lack of hormone receptor expression. It is highly aggressive and difficult to treat with traditional chemotherapeutic regimens. Targeted-therapy using microRNAs (miR) has recently been proposed to improve the treatment of TNBC in the early stages. Here, we explore the roles of miR-483-3p/HDAC8 HDAC8 premiR-vector on tumorigenicity in TNBC patients. Clinical TNBC specimens and three BC cell lines were prepared. miR-483-3p and expression levels were measured using quantitative real-time polymerase chain reaction. Cell cycle progression was assessed by a flow-cytometry method. We also investigated cell proliferation by 3-2, 5-diphenyl tetrazolium bromide assay and colony formation assay. We used a to overexpress miR-483-3p, and a HDAC8-KO-vector for knocking out the endogenous production of HDAC8. Our data showed significant downregulation of miR-483-3p expression in TNBC clinical and cell line samples. The HDAC8 was also upregulated in both tissue specimens and BC cell lines. We found that increased levels of endogenous miR-483-3p affects tumorigenecity of MDA-MB-231. Downregulation of HDAC8 using the KO-vector showed the same pattern. Our results revealed that the miR-483-3p suppresses cellular proliferation and progression in TNBC cell lines via targeting HDAC8. Overall, our outcomes demonstrated the role of miR-483-3p as a tumor suppressor in TNBC and showed the possible mechanism via HDAC8. In addition, targeted treatment of TNBC with miR-483-3p might be considered in the future. 相似文献
995.
Kamel Hessini Karim Ben Hamed Mhemmed Gandour Maroua Mejri Chedly Abdelly Cristina Cruz 《Plant and Soil》2013,370(1-2):163-173
Background and aims
The effects of salt stress on the salt marsh halophyte Spartina alterniflora have been well documented. However, plant responses to combined salinity and ammonium toxicity and the underlying mechanisms are relatively unknown. The aim of the present investigation was to study the effects of both salinity (0, 200 and 500 mM NaCl) and nitrogen form (NO3 ?, NH4 + or NH4NO3) on S. alterniflora.Methods
Plants were cultivated in sandy soil under greenhouse conditions for 3 months. At harvest, growth parameters were measured and leaf samples were analysed for oxidative stress parameters (malondialdehyde, MDA; electrolyte leakage, EL; and hydrogen peroxide, H2O2 concentration) and the activity of antioxidant enzymes (glutathione reductase, GR; superoxide dismutase, SOD; catalase, CAT; ascorbate peroxidase, APX and Guaiacol peroxidase, GPX).Results
In the absence of NaCl, plant growth rate was the highest in the medium containing both nitrogen forms, and the lowest in the medium containing only nitrate. Irrespective of the nitrogen form, plant growth was generally higher at 200 mM NaCl than without salinity. Ammonium-fed plants showed better growth than nitrate-fed plants under high salinity. In the absence of salinity, ammonium-fed plants showed higher SOD, APX, GR, CAT, and GPX activities than nitrate-fed ones. The antioxidant enzymes exhibited higher activity in saline-treated plants. The considerable advantage of NH4 + nutrition to S. alterniflora under saline conditions was associated with high antioxidant enzyme activities, together with low MDA content, EL, and H2O2 concentration.Conclusion
These data clearly demonstrate that NH4 + is more favourable for the growth of S. alterniflora under high salinity than NO3 ?. It is suggested that NH4 + nutrition improves the plant’s capacity to limit oxidative damage by stimulating the activities of the major antioxidant enzymes. 相似文献996.
997.
Slah Ouerhani Karim Bougatef Ismail Soltani Amel Ben Ammar Elgaaied Salem Abbes Samia Menif 《Molecular biology reports》2013,40(6):4109-4114
Mutations in the KRAS gene have been shown to play a key role in the pathogenesis of a variety of human tumours. However the mutational spectrum of KRAS gene differs by organ site. In this study, we have analysed the mutational spectrum of KRAS exon 1 in bladder tumours, colorectal cancer (CRC) and chronic myeloid leukemia (CML). A total of 366 patients were included in the present study (234 bladder tumours, 48 CRC and 84 CML). The KRAS mutations are absent in BCR/ABL1 positive CML. This result suggests that BCR/ABL1 fusion gene and KRAS mutations were mutually exclusive. The frequency of KRAS mutations in bladder cancer was estimated at 4.27 %. All of mutations were found in codon 12 and 90 % of them were detected in advanced bladder tumours. However the correlation between KRAS mutations and tumour stage and grade does not report a statistical significant association. The KRAS mutations occur in 35.41 % of patients with CRC. The most frequent mutations were G12C, G12D and G13D. These mutations were significantly correlated with histological differentiation of CRC (p = 0.024). Although the high frequency of KRAS in CRC in comparison to bladder cancer, these two cancers appear to have the same mutational spectrum (p > 0.05). 相似文献
998.
Dr Nizar Souissi Mohamed Souissi Hichem Souissi Karim Chamari Zouhair Tabka Mohamed Dogui 《Chronobiology international》2013,30(6):1062-1076
The purpose of this study was to determine whether delaying bedtime or advancing rising time by 4 h affects anaerobic performance of individuals the following day in the morning and afternoon. Eleven subjects participated in the study, during which we measured the maximal, peak, and mean powers (i.e., Pmax [force‐velocity test], Ppeak, and Pmean [Wingate test], respectively). Measurements were performed twice daily, at 07∶00 and 18∶00 h, following a reference normal sleep night (RN), a partial sleep deprivation timed at the beginning of the night (SDB), and a partial sleep deprivation timed at the end of the night (SDE), and oral temperature was measured every 4 h. Each of the three experimental conditions was separated by a one‐week period. Our results showed a circadian rhythm in oral temperature, and analysis of variance revealed a significant sleep×test‐time effect on peak power (Ppeak), mean power (Pmean), and maximal power (Pmax). These variables improved significantly from the morning to the afternoon for all three experimental conditions. Whereas the morning‐afternoon improvement in the measures was similar after the RN and SDB conditions, it was smaller following the SDE condition. There was no significant difference in the effect of the two sleep‐deprivation conditions on anaerobic performances at 07∶00 and at 18∶00 h under the SDB condition in comparison with the post‐reference night. However, the performance variables were significantly lower at 18∶00 h after the SDE condition. In conclusion, a 4 h partial sleep deprivation at the end of the night appears to be more disturbing than partial sleep deprivation at the beginning of the night. 相似文献
999.
Dr. Nizar Souissi Nicolas Bessot Karim Chamari Antoine Gauthier Bruno Sesboüé Damien Davenne 《Chronobiology international》2013,30(4):739-748
The purpose of this study was to evaluate the effects of time of day on aerobic contribution during high‐intensity exercise. A group of 11 male physical education students performed a Wingate test against a resistance of 0.087 kg · kg?1 body mass. Two different times of day were chosen, corresponding to the minimum (06:00 h) and the maximum (18:00 h) levels of power. Oxygen uptake (V˙O2) was recorded breath by breath during the test (30 sec). Blood lactate concentrations were measured at rest, just after the Wingate test, and again 5 min later. Oral temperature was measured before each test and on six separate occasions at 02:00, 06:00, 10:00, 14:00, 18:00, and 22:00 h. A significant circadian rhythm was found in body temperature with a circadian acrophase at 18:16±00:25 h as determined by cosinor analysis. Peak power (Ppeak), mean power (Pmean), total work done, and V˙O2 increased significantly from morning to afternoon during the Wingate Test. As a consequence, aerobic contribution recorded during the test increased from morning to afternoon. However, no difference in blood lactate concentrations was observed from morning to afternoon. Furthermore, power decrease was greater in the morning than afternoon. Altogether, these results indicate that the time‐of‐day effect on performances during the Wingate test is mainly due to better aerobic participation in energy production during the test in the afternoon than in the morning. 相似文献
1000.
Karim Vahed 《Ethology : formerly Zeitschrift fur Tierpsychologie》2002,108(12):1065-1075
Sexual coercion in the form of forced copulation is widespread in the animal kingdom and has been documented in several insect taxa. In crickets and bushcrickets (sub‐order Ensifera), however, mating typically involves luring acts as opposed to forcing acts. The mating behaviour of the tettigoniid Anonconotus alpinus Yersin, which is described in this paper, appears to be unique amongst the Tettigoniidae (and possibly amongst the Ensifera) in that it is coercive, involving forced matings. Males did not stridulate immediately prior to mating but instead leapt on passing females, using their anal cerci as pincers to maintain a hold on the female's abdomen (which was sometimes damaged in the process). Males appeared to lack a sexual refractory period and attempted to copulate again as little as 18 s following the previous mating. 相似文献