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111.
Yasser A. Noureldin Nader Fahmy Maurice Anidjar Sero Andonian 《World journal of urology》2016,34(5):733-739
Objective
To assess competency of urology post-graduate trainees (PGTs) in percutaneous renal access (PCA).Methods
Upon obtaining ethics approval and informed consents, PGTs between post-graduate years (PGY-3 to PGY-5) from all four urology programs in Québec were recruited. PCA competency of each participant was assessed objectively by performing task 4 on the PERC Mentor? simulator, where they had to correctly access and pop 7 balloons in 7 different renal calyces and subjectively by the validated Percutaneous Nephrolithotomy—Global Rating Scale (PCNL-GRS).Results
A total of 26 PGTs with a mean age of 29.2 ± 0.7 years participated in this study. When compared with the 21 PGTs without practice, all 5 PGTs who had practiced on the simulator were competent (p = 0.03), performed the task with significantly shorter operative time (13.9 ± 0.7 vs. 4.4 ± 0.4 min; p < 0.001) and fluoroscopy time (9.3 ± 0.6 vs. 3.4 ± 0.4 min; p < 0.001), and had significantly higher PCNL-GRS scores (13 ± 0.6 vs. 20.6 ± 1; p < 0.001) and successful attempts to access renal calyces (23 ± 5 vs. 68.7 ± 11; p = 0.001). According to a pass score of 13/25, thirteen PGTs were competent. Competent PGTs performed the task with significantly shorter fluoroscopy time (9.8 vs. 6.5 min; p = 0.01) and higher percentage of successful attempts to access renal calyces (p < 0.001), higher PCNL-GRS scores (p < 0.001), and lower complications (p = 0.01).Conclusion
The PCNL-GRS in combination with the PERC Mentor? simulator was able to differentiate between competent and non-competent PGTs.112.
Gabriela C. C. C. Maioral Carina Verna Manuel de J. Simões Helena B. Nader Ricardo S. Simões 《Gynecological endocrinology》2016,32(8):617-621
The aim of this study was to evaluate the amount of non- and sulfated glycosaminoglycans in the ovariectomized mice uterus, after treatment with ovarian steroids. For this purpose, 50 adult female mice were divided into five groups with 10 animals/each: control group: CG (ovary intact), and ovariectomized groups: OG (vehicle), EG (estradiol), PG (progesterone) and EPG (estradiol combined to progesterone). The treatments started 30 days after ovariectomy. All the animals were treated for 50 consecutive days. These hormones were administered in a sterile oily solution via gavage. Twenty-four hours after the last treatment, all animals were euthanized, removing the uterine horn for biochemical analyses. To quantify, the hyaluronic acid (HA) used ELISA-like fluorometric assay, and the sulfated glycosaminoglycans (GAGs) used agarose gel electrophoresis. The amount of HA was significantly higher in the group treated with progesterone (PG) compared to the others groups (p?0.05), and in the group treated with estradiol (EG), the amount of chondroitin/dermatan sulfate was significantly higher compared to the others groups (p?0.05), and in the group treated with progesterone (PG), the amount of heparan sulfate was significantly lower compared to the others groups, except to control group (p?0.05). Our results showed that the estroprogestative therapy after long time (50 days) profoundly affected the amount of glycosaminoglycans in uterine. These changes may be indicative of uterine pathology such as the development of tumor. 相似文献
113.
114.
Moore L Lu X Ghebranious N Tyner S Donehower LA 《Mechanisms of ageing and development》2007,128(11-12):717-730
Evidence has accumulated that p53, a prototypical tumor suppressor, may also influence aspects of organismal aging. We have previously described a p53 mutant mouse model, the p53+/m mouse, which is cancer resistant yet exhibits reduced longevity and premature aging phenotypes. p53+/m mice express one full length p53 allele and one truncated p53 allele that is translated into a C-terminal fragment of p53 termed the M protein. The augmented cancer resistance and premature aging phenotypes in the p53+/m mice are consistent with a hyperactive p53 state. To determine how the M protein could increase p53 activity, we examined the M protein in various cellular contexts. Here, we show that embryo fibroblasts from p53+/m mice exhibit reduced proliferation and cell cycle progression compared to embryo fibroblasts from p53+/- mice (with equivalent wild-type p53 dosage). The M protein interacts with wild-type p53, increases its stability, and facilitates its nuclear localization in the absence of stress. Despite increasing p53 stability, the M protein does not disrupt p53-Mdm2 interactions and does not prevent p53 ubiquitination. These results suggest molecular mechanisms by which the M protein could influence the aging and cancer resistance phenotypes in the p53+/m mouse. 相似文献
115.
Haroon Mohammad Ahmed AbdelKhalek Nader S. Abutaleb Mohamed N. Seleem 《International journal of antimicrobial agents》2018,51(6):897-904
Enterococci are commensal micro-organisms present in the gastrointestinal tract of humans. Although normally innocuous to the host, strains of enterococcus exhibiting resistance to vancomycin (VRE) have been associated with high rates of infection and mortality in immunocompromised patients. Decolonization of VRE represents a key strategy to curb infection in highly-susceptible patients. However, there is a dearth of decolonizing agents available clinically that are effective against VRE. The present study found that niclosamide, an anthelmintic drug, has potent antibacterial activity against clinical isolates of vancomycin-resistant Enterococcus faecium (minimum inhibitory concentration 1–8?µg/mL). E. faecium mutants exhibiting resistance to niclosamide could not be isolated even after multiple (10) serial passages. Based upon these promising in-vitro results and the limited permeability of niclosamide across the gastrointestinal tract (when administered orally), niclosamide was evaluated in a VRE colonization-reduction murine model. Remarkably, niclosamide outperformed linezolid, an antibiotic used clinically to treat VRE infections. Niclosamide was as effective as ramoplanin in reducing the burden of vancomycin-resistant E. faecium in the faeces, caecal content and ileal content of infected mice after only 8 days of treatment. Linezolid, in contrast, was unable to decrease the burden of VRE in the gastrointestinal tract of mice. The results obtained indicate that niclosamide warrants further evaluation as a novel decolonizing agent to suppress VRE infections. 相似文献
116.
Adherence to Canada's Food Guide recommendations among Alberta's multi‐ethnic youths is a major concern: findings from the WHY ACT NOW project 下载免费PDF全文
F. Kolahdooz F. Nader M. Daemi S. L. Jang N. Johnston S. Sharma 《Journal of human nutrition and dietetics》2018,31(5):658-669
Background
Dietary habits formed during youth may result in the development of obesity and chronic diseases in adulthood. We aimed to determine the frequency of the consumption of foods and beverages and the degree of adherence to Canada's Food Guide recommendations among multi‐ethnic youths.Methods
Participants were recruited from 12 schools in the Edmonton, Alberta area by use of posters, school newsletters and advertisements. A 30‐item food frequency questionnaire was administered by a trained interviewer to assess dietary intake in a convenience sample of 557 (328 females and 229 males) youths aged 11–23 years; for the purpose of the present study, only the 14–18 years age group was considered in the analysis. Participants were divided by sex and self‐identified ethnicity into four groups [Indigenous, African & Middle Eastern (AME ), Asian, and European]. Statistical analysis of the data was undertaken using t ‐tests, Welch's analysis of variance and Games‐Howell tests. P < 0.05 was considered statistically significant.Results
Vegetables and Fruit recommendations were the least likely to be followed, with 90.7–96.8% of participants in all groups not consuming the recommended number of servings day–1. The mean frequency of fruit consumption was lower among Indigenous youths compared to Asian youths (0.90 versus 1.37 times day–1). A greater proportion of males than females (55.9% versus 44.3%) did not meet the minimum recommendations for Meat and Alternatives (P = 0.016). The percentage of youths not adhering to recommendations for Milk and Alternatives was 81.7% for Indigenous, 73.3% for AME , 78.6% for Asian and 63.5% for European youths. Indigenous youths more frequently consumed potato chips and soft drinks compared to other ethnic youths. The most frequently consumed beverage was milk (1.25 times day–1).Conclusions
The majority of youths did not consume minimum daily recommended servings of Vegetables and Fruit, Milk and Alternatives, and/or Meat and Alternatives food groups. Evidence‐based dietary interventions and public health strategies are needed.117.
118.
Nader Ayobian-Markazi Tahereh Fourootan Atieh Zahmatkesh 《Lasers in medical science》2014,29(1):47-53
Erbium:yttrium–aluminum–garnet (Er:YAG) laser treatment is an effective option for the removal of bacterial plaques. Many studies have shown that Er:YAG lasers cannot re-establish the biocompatibility of titanium surfaces. The aim of this study was to evaluate the responses of the human osteoblast-like cell line, SaOs-2, to sand-blasted and acid-etched (SLA) titanium surface irradiation using different energy settings of an Er:YAG laser by examining cell viability and morphology. Forty SLA titanium disks were irradiated with an Er:YAG laser at a pulse energy of either 60 or 100 mJ with a pulse frequency of 10 Hz under water irrigation and placed in a 24-well plate. Human osteoblast-like SaOs-2 cells were seeded onto the disks in culture media. Cells were then kept in an incubator with 5 % carbon dioxide at 37 °C. Each experimental group was divided into two smaller groups to evaluate cell morphology by scanning electron microscope and cell viability using 3-4,5-dimethylthiazol 2,5-diphenyltetrazolium bromide test. In both the 60 and the 100 mJ experimental groups, spreading morphologies, with numerous cytoplasmic extensions, were observed prominently. Similarly, a majority of cells in the control group exhibited spreading morphologies with abundant cytoplasmic extensions. There were no significant differences among the laser and control groups. The highest cell viability rate was observed in the 100 mJ laser group. No significant differences were observed between the cell viability rates of the two experimental groups (p?=?1.00). In contrast, the control group was characterized by a significantly lower cell viability rate (p?<?0.001). Treatments with an Er:YAG laser at a pulse energy of either 60 or 100 mJ do not reduce the biocompatibility of SLA titanium surfaces. In fact, modifying SLA surfaces with Er:YAG lasers improved the biocompatibility of these surfaces. 相似文献
119.
Hossein Poustchi Maryam Darvishian Zahra Mohammadi Amaneh Shayanrad Alireza Delavari Ayad Bahadorimonfared Saeid Eslami Shaghayegh Haghjooy Javanmard Ebrahim Shakiba Mohammad Hossein Somi Amir Emami Nader Saki Ahmad Hormati Alireza Ansari-Moghaddam Majid Saeedi Fatemeh Ghasemi-Kebria Iraj Mohebbi Fariborz Mansour-Ghanaei Reza Malekzadeh 《The Lancet infectious diseases》2021,21(4):473-481
120.
EDEN-dependent translational repression of maternal mRNAs is conserved between Xenopus and Drosophila. 下载免费PDF全文
Nader Ezzeddine Luc Paillard Michele Capri Dominique Maniey Therese Bassez Ounissa Ait-Ahmed H Beverley Osborne 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(1):257-262
Translational control is a key level in regulating gene expression in oocytes and eggs because many mRNAs are synthesized and stored during oogenesis for latter use at various stages of oocyte maturation and embryonic development. Understanding the molecular mechanisms that underlie this translational control is therefore crucial. Another important issue is the evolutionary conservation of these mechanisms--in other words the determination of their universal and specific aspects. We report here a comparative analysis of a translational repression mechanism that depends on the EDEN (embryo deadenylation element) element. This small cis-acting element, localized in the 3' untranslated region of c-mos and Eg mRNAs, was shown to be involved in a deadenylation process. We demonstrate here that in Xenopus embryos, mRNAs that contain an EDEN are translationally repressed. Next, transgenic flies were used to study the effect of the EDEN motif on translation in Drosophila oocytes. We show that this element also causes the translational repression of a reporter gene in Drosophila demonstrating that the EDEN-dependent translational repression is functionally conserved between Xenopus and Drosophila. 相似文献