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Rafat S. Mohtasib Jamaan S. Alghamdi Salah M. Baz Haya F. Aljoudi Ahmed M. Masawi Aman A. Jobeir 《Neurosciences (Riyadh, Saudi Arabia)》2021,26(1):45
Objectives:To assess a baseline assessment using developed functional magnetic resonance imaging (fMRI) language paradigms for Arabic-speakers.Methods:24-healthy right-handed volunteers scanned on a 3.0 Tesla MRI machine. For fMRI, a BOLD-sensitive sequence used to measure signals over time across 6 language paradigms: rhyming (RH), semantic category generations (SCG), silent word generation (SWG), verb generation picture (VGp), verb generation word (VGw), and verb generation audio (VGa). fMRI data was analyzed using FMRIB Software Library (FSL).Results:We found that VGa, SWG, VGw and VGp robustly activated language-related regions in the dominant hemisphere. RH and SCG failed to adequately define these activation regions but this may be related to the study’s preliminary nature and limitations. After assessment of their validity, considerable activation of the inferior frontal gyrus during VGa, SWG, VGw and VGp suggests that these paradigms have the potential for localizing of Broca’s area in native Arabic speakers.Conclusion:Set of well adapted, and evidence-based, fMRI paradigms were established for Arabic-speakers to enable accurate and sufficient localization and lateralization of the language area. After validation, these paradigms may provide sequences for accurate localization of brain language areas, and could be used as a presurgical evaluation tool.Functional magnetic resonance imaging (fMRI) allows precise, and non-invasive, localization and lateralization of brain functions. Clinically, these techniques have considerable success, and hold great potential in the management of a variety of neurological disorders. One of the most promising clinical applications of fMRI is presurgical linguistic mapping.1-5 The 3 classical language areas that are involved in language production and processing are Broca’s and Wernicke’s areas, and angular gyrus. Wernicke’s area can be described as a receptive region, for processing and integrating auditory sensory information, while Broca’s area can be described as a productive region, for making vocal signals, and meaningful words or sentences. The latter includes pars opercularis and triangularis. The angular gyrus area is particularly involved in reading and transitioning between written and spoken forms of language. Injury to language regions produces noticeable clinical deficits, and the location of these regions may become difficult to assess without advanced anatomical imaging such as fMRI. Internationally, fMRI replaces the more invasive Wada test (also known as the intracarotid sodium amobarbital procedure) in lateralizing language and memory at some centers.6,7Language is a highly complex system that markedly varies across individuals. Patients native language affects brain activation responses during fMRI scans.8-13 As such, language paradigms for presurgical fMRI mapping should be developed and validated using native language paradigms. Language dominance of the left cerebral hemisphere has been well researched and established, but native language and social factors were also reported to play a key role in cortical association of verbal processing.8,14-16Although language localization using fMRI has been routinely used in western countries, and more recently in an Arabic country,17 studies clearly demonstrated that different cultures may process language in different manners, using different brain mechanisms.8,14-16 Existing language paradigms, created for non-Arabic speaking patients, require major modifications before applying them in examining native Arabic speakers.17Language lateralization is another broadly used clinical application of fMRI. Concordance with Wada test has long been demonstrated and validated in the literature using paradigms with various tasks such as verbal fluency, comprehension, and semantic judgment .18-21 These have shown that concordance with Wada test can reach 90% in temporal lobe epilepsy, especially in left-dominant patients. A slightly lower concordance was achieved in right-dominant patients. Although fMRI language lateralization works well for patients with typical language dominance, clinicians need to be careful when interpreting results of patients with atypical language representation.22Semitic languages such as Arabic differ from other languages in many aspects, including orthography (including diacritics), phonology, and syntax. Therefore, significant research in developing and validating language paradigms for Arabic is required. To our knowledge, very few studies in this domain have been carried out.17,23 One developed several language and memory paradigms in neurological patients, while emphasizing consideration for educational and cultural adjustments,17 and the other examined neuronal correlates of diacritics (vs. lack of thereof) in 11 healthy men.23We aim to establish tasks adapted to the Arabic language, that also reliably activate Broca’s and Wernicke’s areas in a relatively short scanning time. This study is a baseline assessment using 6 developed fMRI language paradigms for Arabic-speaking presurgical candidates. The desired outcome of this work is to create a set of Arabic language localization protocols, along with standard operating procedures. 相似文献
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Mansour Issaoui Salah Jellali Antonis A. Zorpas Patrick Dutournie 《Sustainable Chemistry and Pharmacy》2022
Although water is essential for human survival and has always been critical to the social and economic growth of the world, it is unfortunately distributed irregularly worldwide and is threatened by countless source of pollution. Addressing the issue of water resources sustainability is extremely crucial for societies in order to maintain safety as well as social, ecological and economic progress. The issue of water scarcity has pushed the world to develop adequate technologies and approaches for sustainable water resources management. In addition, to seawater and brackish water, industrial and municipal wastewater are also considered to be important available resources that need to be taken into consideration to increase sustainability and at the same time to meet SDGs. Indeed, as the population grows, agricultural, domestic and industrial activities produce large amounts of wastewaters that can be treated and reused in variety of purposes considering circular economy philosophy. Nowadays, wastewaters are treated in order to be reused for industrial, agricultural and other domestic purposes. In this context, membrane technology is a preferred choice for treatment of water from different wastewater streams for reuse in a more sustainable way, taking into account the philosophy of circular economy and the targets set from UN. This review discusses the links between the concept of sustainability and the treatment of water resources, including wastewaters with membrane technology. It provides a tangible framework for presenting the relevant challenges and future prospects but also the benefits that will come. The practical results of the research serve as reference point for stakeholders, policy makers dealing with sustainable water development strategies considering SDGs and circular economy. 相似文献
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Omar Kujan Ibrahim Alzoghaibi Saleh Azzeghaiby Mohammed Alsakran Altamimi Bassel Tarakji Salah Hanouneh Majdy Idress Faris Q Alenzi Mazhar Iqbal Shahama Taifour 《Journal of cancer education》2014,29(4):735-738
Oral cancer awareness among future dental practitioners may have an impact on the early detection and prevention of oral cancer. A cross-sectional survey was undertaken to assess the current knowledge of future Saudi dentists on oral cancer and their opinions on oral cancer prevention. A pretested questionnaire was sent to 550 undergraduate dental students in the fourth, fifth, and sixth year of the Al-Farabi College for Dentistry and Nursing, Riyadh, Saudi Arabia. Questions relating to knowledge of oral cancer, risk factors, and opinions on oral cancer prevention and practices were posed. Four hundred seventy-nine students returned the questionnaire (87.1 %). Eighty-one percent of respondents correctly answered questions relating to oral cancer awareness. Eighty-seven percent of respondents felt confident in performing a systematic oral examination to detect changes consistent with oral malignancy. Interestingly, 57 % of respondents had seen the use of oral cancer diagnostics aids. Thirty-seven percent of respondents felt inadequately trained to provide tobacco and alcohol cessation advice. There is a need to reinforce the undergraduate dental curriculum with regards to oral cancer education; particularly in its prevention and early detection. Incorporating the use of oral cancer diagnostic aids should be made mandatory. 相似文献
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Erythropoietic activity is known to be closely associated with marrow iron uptake. A modification of the standard measure of plasma iron turnover has been developed in which erythron transferrin uptake (ETU) rather than iron uptake has been calculated. The ETU has the advantage of providing a parameter of erythroid marrow activity independent of change produced by plasma iron and transferrin saturation. Measurements in 80 patients with anemia were compared to the normal value of 60 +/- 12 mumol/L whole blood/d. The mean ETU for ten patients with severe aplastic anemia and for six patients with pure red-cell aplasia were 12 +/- 8 and 12 +/- 11 mumol/L whole blood/d, respectively. In ten transfusion-dependent patients with renal failure under dialysis therapy, the mean value was 35 +/- 11, while ten other dialyzed patients who were transfusion independent had a mean ETU of 73 +/- 21 mumol/L whole blood/d. Sixteen patients with hemolytic anemia had an average ETU of 400 +/- 130, while 28 patients with ineffective erythropoiesis had a mean value of 474 +/- 147 mumol/L whole blood/d. While patients with hypoproliferative anemia showed no relation between the severity of anemia and ETU, those with hyperproliferative erythroid marrow showed increasing values as the anemia became more severe. Sequential measurements in patients with aplastic anemia under treatment and in thalassemic patients under transfusion therapy showed the value of this measurement in monitoring the effects of treatment on erythroid marrow activity. It is concluded that the measurement of ETU provides a more direct ferrokinetic evaluation of erythroid activity in anemic states. 相似文献