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951.
Alaa Wageh Maha Houssen Ahmed Gibreel Mohamed Sayed Abdelhafez Mona Abo-bakr El-Hussiny Ola Ali Elemam Noha El-Adawi 《Middle East Fertility Society Journal》2018,23(4):370-372
Aim
To investigate whether atrial natriuretic peptide (ANP) level is altered in polycystic ovarian syndrome (PCOS) patients with clomiphene citrate (CC) resistant and whether it correlates with insulin sensitivity markers.Methods
Serum ANP, insulin and glucose levels and the homeostasis model assessment for insulin resistance index (HOMA-IR) were evaluated among a group of PCOS women with CC resistance (n?=?40). A control group (n?=?30) was selected from healthy women with regular menstrual cycles.Results
Serum ANP level was significantly lower in the study group than in the control group (0.74?±?1.1?ng/ml vs 3.17?±?1.9?ng/ml; P?<?0.001). The HOMA-IR index was significantly higher in the study than in the control group (3.2?±?1.2 vs 1.2?±?0.74; P?=?0.01). There was no correlation between the ANP level and HOMA-IR index neither in the study group (r?=??0.09, P?=?0.63) nor in the control group (r?=??0.15, P?=?0.35).Conclusion
The PCOS patients with CC resistant have reduced plasma ANP level and increases HOMA-IR index compared with healthy regular menstruating women. Low serum ANP level may be involved in the metabolic features of CC resistant PCOS. 相似文献952.
Emergence of the neural network underlying phonological processing from the prereading to the emergent reading stage: A longitudinal study
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Xi Yu Talia Raney Meaghan V. Perdue Jennifer Zuk Ola Ozernov‐Palchik Bryce L. C. Becker Nora M. Raschle Nadine Gaab 《Human brain mapping》2018,39(5):2047-2063
Numerous studies have shown that phonological skills are critical for successful reading acquisition. However, how the brain network supporting phonological processing evolves and how it supports the initial course of learning to read is largely unknown. Here, for the first time, we characterized the emergence of the phonological network in 28 children over three stages (prereading, beginning reading, and emergent reading) longitudinally. Across these three time points, decreases in neural activation in the left inferior parietal cortex (LIPC) were observed during an audiovisual phonological processing task, suggesting a specialization process in response to reading instruction/experience. Furthermore, using the LIPC as the seed, a functional network consisting of the left inferior frontal, left posterior occipitotemporal, and right angular gyri was identified. The connection strength in this network co‐developed with the growth of phonological skills. Moreover, children with above‐average gains in phonological processing showed a significant developmental increase in connection strength in this network longitudinally, while children with below‐average gains in phonological processing exhibited the opposite trajectory. Finally, the connection strength between the LIPC and the left posterior occipitotemporal cortex at the prereading level significantly predicted reading performance at the emergent reading stage. Our findings highlight the importance of the early emerging phonological network for reading development, providing direct evidence for the Interactive Specialization Theory and neurodevelopmental models of reading. 相似文献
953.
Engelsen O 《Nutrients》2010,2(5):482-495
This paper reviews the main factors influencing the synthesis of vitamin D, with particular focus on ultraviolet radiation exposure. On the global level, the main source of vitamin D is the sun. The effect of solar radiation on vitamin D synthesis depends to some extent on the initial vitamin D levels. At moderate to high latitudes, diet becomes an increasingly important source of vitamin D due to decreased solar intensity and cold temperatures, which discourage skin exposure. During the mid-winter season, these factors result in decreased solar radiation exposure, hindering extensively the synthesis of vitamin D in these populations. 相似文献
954.
Oxygen is critical for multicellular existence. Its reduction to water by the mitochondrial electron transport chain helps supply the metabolic demands of human life. The incompletely reduced, reactive oxygen byproducts of this reaction, however, can be quite toxic. In this review, we explore the mechanisms responsible for maintaining oxygen homeostasis and the consequences of their dysfunction. With an eye toward defining clinical care guidelines for the management of critically ill neonates, we present evidence describing the role of physiologic hypoxia during development and the adverse consequences of hyperoxia in-term as well as preterm infants. 相似文献
955.
Skoog T Elomaa O Pasonen-Seppänen SM Forsberg S Ahokas K Jeskanen L Pärssinen J Tiala I Rollman O Lohi J Saarialho-Kere U 《The Journal of investigative dermatology》2009,129(1):119-130
In the skin, expression of several matrix metalloproteinases (MMPs) occurs in response to tissue injury, tumorigenesis, angiogenesis, apoptosis, and inflammation. The recently cloned MMP-21 has been implicated in skin development and various epithelial cancers. In this study, we found that it is also expressed by differentiated keratinocytes (KCs) in various benign skin disorders, in which it was not associated with KC apoptosis or proliferation, and in organotypic cultures. Furthermore, MMP-21 was induced in keratinocytes in association with increased calcium and presence of the differentiation marker filaggrin. In stably transfected A431 and HEK293 cell lines, MMP-21 increased invasion of cells but did not associate with increased apoptosis, proliferation, or epithelial-to-mesenchymal transition. Of various agents tested in HaCaT cell cultures, only retinoic acid (10(-6) M) and staurosporine (2.5 x 10(-8) M) upregulated MMP-21 mRNA and protein expression, whereas tumor promoters, hormones, or dexamethasone were without effect. Our results suggest that MMP-21 may be an important protease in the terminal differentiation of keratinocytes. 相似文献
956.
Retrospective Study of the Effect of Statins on the Outcome of Lung Cancer Patients,University of Cincinnati Experience
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Ola GaberIhab EldessoukiRammey HassanMohamed MagdyJohn C MorrisNagla Abdel Karim 《Asian Pacific journal of cancer prevention》2019,20(8):2391-2396
Objectives: Numerous studies addressed the effect of statin on cancer patients. The aim of this study is to define theeffect of statin administration with chemotherapy on the patients’ outcomes. Methods: We retrospectively researchedthe database of the University of Cincinnati cancer to identify lung cancer patients who received statins (S+, n=41)during their treatment in our institute. We also, retrieved data for contemporaneously treated patients who did notreceive statins (S-, n=159) as a control arm. Clinico-demographical data and overall survival (OS) were analyzed usingPearson’s Chi-square (χ2) test and Kaplan-Meier survival curves with Log-rank test. Adjustment using Cox proportionalhazard ratios (HR) were done based on (age, gender, race and stage) to identify effect of statins on their outcomes.Results: The median age for S+ was 64y (IQR; 55-69) and 71.2% of the patients were white. Histopathology was55.4% and 31.7% for adenocarcinoma and squamous cell carcinoma, respectively. Fifty-six percent were stage IV ineach study arm and the median OS was14.9 m. Median OS was insignificantly lower in S–ve arm (13.7 vs 15.6 months;P=0.652, HR=0.91, 95%CI 0.52-1.57). Our results show that after different types of adjustments, S+ did not showsurvival advantage (P>0.05) compared to the control arm. Conclusion: While showing an increase in overall survivalin patients with advanced lung cancer, the results of this study did not reach statistical significance. This could be duefor the small sample size of this retrospective study. 相似文献
957.
Hisham F. Bahmad Houda Samman Alissar Monzer Ola Hadadeh Katia Cheaito Rana Abdel‐Samad Berthe Hayar Claudio Pisano Hiba Msheik Yen‐Nien Liu Nadine Darwiche Wassim Abou‐Kheir 《Molecular carcinogenesis》2019,58(7):1208-1220
Retinoids are vitamin A derivatives that regulate crucial biological processes such as cellular proliferation, apoptosis, and differentiation. The use of natural retinoids in cancer therapy is limited due to their toxicity and the acquired resistance by cancer cells. Therefore, synthetic retinoids were developed, such as the atypical adamantyl retinoid ST1926 that provides enhanced bioavailability and reduced toxicity. We have assessed the in vitro and in vivo antitumor properties and mechanism of action of ST1926 in targeting cancer stem‐like cells population of human prostate cancer (PCa) cell lines, DU145 and PC3, and mouse PCa cell lines, PLum‐AD and PLum‐AI. We demonstrated that ST1926 substantially reduced proliferation of PCa cells and induced cell cycle arrest, p53‐independent apoptosis, and early DNA damage. It also decreased migration and invasion of PCa cells and significantly reduced prostate spheres formation ability in vitro denoting sufficient eradication of the self‐renewal ability of the highly androgen‐resistant cancer stem cells. Importantly, ST1926 potently inhibited PCa tumor growth and progression in vivo. Our results highlight the potential of ST1926 in PCa therapy and warrant its clinical development. 相似文献
958.
Mohamed Rizk Ola Rizq Motohiko Oshima Yaeko Nakajima‐Takagi Shuhei Koide Atsunori Saraya Yusuke Isshiki Tetsuhiro Chiba Satoshi Yamazaki Anqi Ma Jian Jin Atsushi Iwama Naoya Mimura 《Cancer science》2019,110(12):3695-3707
Polycomb repressive complex 2 (PRC2) components, EZH2 and its homolog EZH1, and PI3K/Akt signaling pathway are focal points as therapeutic targets for multiple myeloma. However, the exact crosstalk between their downstream targets remains unclear. We herein elucidated some epigenetic interactions following Akt inhibition and demonstrated the efficacy of the combined inhibition of Akt and PRC2. We found that TAS‐117, a potent and selective Akt inhibitor, downregulated EZH2 expression at the mRNA and protein levels via interference with the Rb‐E2F pathway, while EZH1 was compensatively upregulated to maintain H3K27me3 modifications. Consistent with these results, the dual EZH2/EZH1 inhibitor, UNC1999, but not the selective EZH2 inhibitor, GSK126, synergistically enhanced TAS‐117‐induced cytotoxicity and provoked myeloma cell apoptosis. RNA‐seq analysis revealed the activation of the FOXO signaling pathway after TAS‐117 treatment. FOXO3/4 mRNA and their downstream targets were upregulated with the enhanced nuclear localization of FOXO3 protein after TAS‐117 treatment. ChIP assays confirmed the direct binding of FOXO3 to EZH1 promoter, which was enhanced by TAS‐117 treatment. Moreover, FOXO3 knockdown repressed EZH1 expression. Collectively, the present results reveal some molecular interactions between Akt signaling and epigenetic modulators, which emphasize the benefits of targeting PRC2 full activity and the Akt pathway as a therapeutic option for multiple myeloma. 相似文献
959.
Haugejorden O Klock KS Astrøm AN Skaret E Trovik TA 《Community dentistry and oral epidemiology》2008,36(3):269-278
Abstract – Objective: To assess inequality in dental status associated with educational level, gross personal and family income among Norwegian adults. Methods: Data were collected by Norway's Central Bureau of Statistics in November–December 2003. A two‐stage, proportional random sample comprising 2000 persons aged 16–79 years was drawn from the national population register. Information became available for 1309 subjects by interview. The present analyses pertain to 1092 subjects aged 25–79 years (response rate 66%, mean age 47.9 years). Results: Of the respondents, 3% were edentulous and 9% had fewer than 20 teeth. The mean number of teeth was 27.1 (SD 7.0). In multiple logistic regression analysis, low gross personal and adjusted family income were associated with increased likelihood of having fewer than 20 natural teeth (OR = 2.84, 95% CI 1.58, 5.10; OR = 3.63, 95% CI 1.99, 6.62, respectively). Educational level was significantly associated with dental status in bivariate but not in multivariate analyses, except once among males. The predictors of socio‐economic inequality in dental status accounted for a limited proportion of explained variance (Nagelkerke's R2) when controlling for age, place of residence, perceived oral health compared with others, perceived importance of oral health, dental attendance and smoking. Conclusion: Socio‐economic inequality in dental status persists among Norwegians aged 25–79 years but absolute differences have decreased during the last 30 years. The findings are encouraging but challenging as far as choice of strategy for further reduction of differences in tooth loss. 相似文献
960.
Ola Mohamed Ragab Hania Salah Zayed Enas Abolkheir Abdelaleem Ayman Eid Girgis 《The Egyptian Rheumatologist》2017,39(2):69-74