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Bibliometrics of Sudanese scientific publications: Subjects, institutions, collaboration, citation and recommendations
No full text[[abstract]]Introduction:
Sudan is the third largest country in Africa and has rich reserves of petroleum and other ground resources, but its per capita Gross Domestic Product is only $808 and researchers work in insufficient institutional facilities and with little funding. Previous studies about its scientific productivity have been limited to specific subjects and relatively short periods, with no large analyses until now.
Objective:
To analyze the scientific output of Sudan in depth, considering all research areas and several decades of scientific activity.
Methods:
We retrieved the documents with “Sudan” in field country in the Science Citation Index Expanded for the period 1900-2019.
Results:
We retrieved over 9 000 publications and found that most were articles; that citation was higher for review articles and book chapters, and that this index mostly covered articles in English. Beginning in 1972, the number of publications in this database has increased rapidly. The citation lifespan indicates slow growth in the Sudanese scientific literature, and collaboration is frequent both nationally and internationally, possibly because the scarce resources make collaboration almost compulsory. Most external collaboration is done with Saudi Arabia but citation is higher for articles resulting from international megaprojects, led by Europe and the USA, in which Sudanese researchers play secondary roles. Research focusses on applied technological subjects with little innovation value. Women play a smaller role in Sudanese science.
Conclusions:
Our recommendations for Sudanese science include increasing the number of women in leading research positions; providing funding directly to researchers (i.e., bypassing bureaucratic bodies); increasing basic research to avoid stagnation; training Sudanese researchers for leading positions; and identifying specific research areas where Sudan can lead in its region
Daidzein Synergizes with Gefitinib to Induce ROS/JNK/c-Jun Activation and Inhibit EGFR-STAT/AKT/ERK Pathways to enhance Lung Adenocarcinoma cells chemosensitivity
No full text[[abstract]]Lung cancer is the major cause of cancer associated mortality. Mutations in EGFR have been implicated in lung cancer pathogenesis. Gefitinib (GF) is a RTKI (receptor tyrosine kinase inhibitor) first-choice drug for EGFR mutated advanced lung cancer. However, drug toxicity and cancer cell resistance lead to treatment failure. Consequently, new therapeutic strategies are urgently required. Therefore, this study was aimed at identifying tumor suppressive compounds that can synergistically improve Gefitinib chemosensitivity in the lung cancer treatment. Medicinal plants offer a vast platform for the development of novel anticancer agents. Daidzein (DZ) is an isoflavone compound extracted from soy plants and has been shown to possess many medicinal benefits. The anticancer potential of GF and DZ combination treatment was investigated using MTT, western blot, fluorescent microscopy imaging, flow cytometry and nude mice tumor xenograft techniques. Our results demonstrate that DZ synergistically induces c-Jun nuclear translocation through ROS/ASK1/JNK and downregulates EGFR-STAT/AKT/ERK pathways to activate apoptosis and a G0/G1 phase cell cycle blockade. In in-vivo, the combination treatment significantly suppressed A549 lung cancer cells tumor xenograft growth without noticeable toxicity. Daidzein supplements with current chemotherapeutic agents may well be an alternative strategy to improve the treatment efficacy of lung adenocarcinoma
Dendrobium nobile protects retinal cells from UV-induced oxidative stress damage via Nrf2/HO-1 and MAPK pathways
No full text[[abstract]]Ethnopharmacological relevance: Excessive UV irradiation and ROS exposure are the main contributors of ocular pathologies. Pseudobulb of Dendrobium nobile Lindl. is one of the sources of Shihu and has long been used in traditional Chinese medicine as a tonic to nourish stomach, replenish body fluid, antipyretic and anti-inflammation.
Aim of study: This study aimed to investigate whether D. nobile could protect ocular cells against oxidative stress damage.
Materials and methods: Retinal-related cell lines, ARPE-19 and RGC-5 cells, were pretreated with D. nobile extracts before H2O2- and UV-treatment. Cell viability and the oxidative stress were monitored by sulforhodamine B (SRB) and SOD1 and CAT assay kits, respectively. The oxidative stress related proteins were measured by Western blotting.
Results: Under activity-guided fractionation, a sesquiterpene-enriched fraction (DN-2) and a major component (1) could ameliorate H2O2- and UV-induced cytotoxicity and SOD1 and CAT activity, but not dendrobine, the chemical marker of D. nobile. Western blotting showed both DN-2 and compound 1 protected ARPE-19 cells against UV-induced oxidative stress damage by regulating MAPK and Nrf2/HO-1 signaling.
Conclusion: Our results suggest D. nobile extract protects retinal pigment epithelia cells from UV- and oxidative stress-damage, which may have a beneficial effect on eye diseases
Galangin Reverses H 2 O 2-Induced Dermal Fibroblast Senescence via SIRT1-PGC-1α/Nrf2 Signaling
No full text[[abstract]]UV radiation and H2O2 are the primary factors that cause skin aging. Both trigger oxidative stress and cellular aging. It has been reported that deacetylase silent information regulator 1 (SIRT1), a longevity gene, enhances activation of NF-E2-related factor-2 (Nrf2), as well as its downstream key antioxidant gene hemeoxygenase-1 (HO-1), to protect cells against oxidative damage by deacetylating the transcription coactivator PPARγ coactivator-1α (PGC-1α). Galangin, a flavonoid, possesses anti-oxidative and anti-inflammatory potential. In the present study, we applied Ultraviolet B/H2O2-induced human dermal fibroblast damage as an in vitro model and UVB-induced photoaging of C57BL/6J nude mice as an in vivo model to investigate the underlying dermo-protective mechanisms of galangin. Our results indicated that galangin treatment attenuates H2O2/UVB-induced cell viability reduction, dermal aging, and SIRT1/PGC-1α/Nrf2 signaling activation. Furthermore, galangin treatment enhanced Nrf2 activation and nuclear accumulation, in addition to inhibiting Nrf2 degradation. Interestingly, upregulation of antioxidant response element luciferase activity following galangin treatment indicated the transcriptional activation of Nrf2. However, knockdown of SIRT1, PGC-1α, or Nrf2 by siRNA reversed the antioxidant and anti-aging effects of galangin. In vivo evidence further showed that galangin treatment, at doses of 12 and 24 mg/kg on the dorsal skin cells of nude mice resulted in considerably reduced UVB-induced epidermal hyperplasia and skin senescence, and promoted SIRT1/PGC-1α/Nrf2 signaling. Furthermore, enhanced nuclear localization of Nrf2 was observed in galangin-treated mice following UVB irradiation. In conclusion, our data indicated that galangin exerts anti-photoaging and antioxidant effects by promoting SIRT1/PGC-1α/Nrf2 signaling. Therefore, galangin is a potentially promising agent for cosmetic skin care products against UV-induced skin aging
Error patterns of facial emotion recognition in patients with schizophrenia
No full text[[abstract]]Error patterns of facial emotion recognition (FER) indicate how individuals misinterpret others' facial expressions, which helps clinicians to manage related deficits. However, previous investigations are limited and may have been biased due to methodological issues (e.g., no consideration of response bias). This study aimed to propose a detectability index (d') for adjusting response bias and examine the error patterns of FER in patients with schizophrenia. Responses to 168 photos showing seven basic emotions, obtained from 351 patients with schizophrenia and 101 healthy adults, were extracted from a previous study. The differences in the d's between the two groups (Δd') were calculated to examine the error patterns of FER among the seven emotions. The findings were generally overlapped with those identified by the traditional confusion matrix. Four error patterns were found. First, the patients were insensitive to some negative emotions (i.e., sadness [Δd' = 0.83] and fear [Δd' = 0.72]). Second, they misrecognized happy faces as showing negative emotions (e.g., disgust [Δd' = 0.43] and sadness [Δd' = 0.37]). Third, they misinterpreted surprised faces as all the other emotions (Δd' = 0.41-0.87), except neutral. Fourth, they confused some negative emotions (e.g., misrecognizing fear as anger [Δd' = 0.87]). Our findings suggest that patients with schizophrenia show four error patterns of FER compared to healthy adults. Accordingly, interventions could be selected to improve their sensitivity to faces with negative emotions, differentiation of faces among positive and negative emotions, understanding of surprised faces, and discrimination of faces with negative emotions
Induction of Human Umbilical Mesenchymal Stem Cell Differentiation Into Retinal Pigment Epithelial Cells Using a Transwell-Based Co-culture System
No full text[[abstract]]There is an increasing interest in generating retinal pigment epithelial (RPE) cells from stem cells for treating degenerative eye diseases. However, whether human umbilical cord mesenchymal stem cells (HUCMSCs) can differentiate into RPE-like cells in a co-culture system has not been fully understood. In this study, induction of HUCMSC differentiation into RPE-like cells was performed by co-culturing HUCMSCs and a human RPE-like cell line (ARPE19) in a transwell system and then analyzed for biomarkers using quantitative reverse transcription polymerase chain reaction (RT-PCR) and immunofluorescence staining technique. Moreover, the functional characterization of induced cells was carried out by examining their phagocytic and neurotrophic factor-secreting activities. Our results showed that mRNA expressions of RPE-specific markers-MITF, OTX2, RPE65, PEDF, PME17, and CRALBP-and protein markers-RPE65, CRALBP, and ZO-1-were significantly increased in HUCMSC-derived RPE-like cells. Functional characteristic studies showed that these induced cells were capable of engulfing photoreceptor outer segments and secreting brain-derived neurotrophic factor (BDNF) and glial-derived neurotrophic factor (GDNF), which are typical functions of RPE-like cells. Overall, the study findings indicate that the morphology and proliferation of HUCMSCs can be maintained in a serum-free medium, and differentiation into RPE-like cells can be induced by simply co-culturing HUCMSCs with ARPE19 cells. Thus, the study provides fundamental information regarding the clinical-scale generation of RPE-like cells from HUCMSCs
Tanshinone IIA inhibits Leu27IGF-II-induced insulin-like growth factor receptor II signaling and myocardial apoptosis via estrogen receptor-mediated Akt activation
No full text[[abstract]]Different stress condition stimulates the expression level of insulin-like growth factor receptor II (IGF-IIR) in cardiomyoblasts that lead to apoptosis. Tanshinone IIA (TSN), a pharmacologically active component from Danshen, has been shown cardioprotective effects against cardiac apoptosis induced by several stress conditions. Therefore, this study was conducted to assess the cardioprotective effects of TSN IIA mediated through the estrogen receptor (ER) in order to inhibit the Leu27IGF-II-enhanced IGF-IIR-mediated cardiac apoptosis. The estrogenic activity of TSN IIA was examined after myocardial cells were pretreated with the ER antagonist, and inhibited the phospho-inositide-3 kinase (PI3K). Here, we found that TSN IIA significantly induced ER that phosphorylated Akt. Further, Akt activation considerably suppressed the Leu27IGF-II induced IGF-IIR expression level and the downstream effectors, including Gαq and calcineurin as well as mitochondrial dependent apoptosis proteins including Bad, cytochrome c, and active caspase-3 that result in cardiac apoptosis resistance. However, the western blot analysis, JC-1 staining, and terminal deoxynucleotide transferase-mediated dUTP nick end labeling assay revealed that TSN IIA attenuated Leu27IGF-II-induced IGF-IIR mediated cardiac apoptosis was reversed by an ER antagonist such as ICI 182780, and PI3K inhibition. All these findings demonstrate that TSN IIA exerts estrogenic activity, which can activate PI3K-Akt pathway, and thereby inhibits Leu27IGFII induced IGF-IIR mediated cardiac apoptosis. Thus, TSN IIA can be considered as an effective therapeutic strategy against IGF-IIR signaling cascade to suppress cardiac apoptosis
The Trend of Bacterial Nanocellulose Research Published in the Science Citation Index Expanded From 2005 to 2020: A Bibliometric Analysis
No full text[[abstract]]To gain insight into the trend of bacterial nanocellulose research, a bibliometric analysis was performed using the Science Citation Index Expanded database from 2005 to 2020. The study concentrated on the publication’s performance in terms of annual outputs and citations, mainstream journals, categories of the Web of Sciences, leading countries, prominent institutions, and trends in research. Current research priorities and future trends were analyzed after summarizing the most commonly used keywords extracted from words in the paper title analysis, authors’ keyword analysis, and KeyWords Plus. The findings revealed that the annual output in the form of scholarly articles on bacterial nanocellulose research steadily increased during the first quartile of the study period, followed by a very rapid increase in the last five-years of the study. Increasing mechanical strength would remain the main future focus of bacterial nanocellulose research to create its scope in different field of applications
臺灣青年 COVID 19 期間電子煙使用易感之調查與防制
No full text[[abstract]]現階段臺灣正處疫情期間，我們對於臺灣青年的電子菸使用動機及易感知之甚少。透過社會學習理論與結果預期模型文獻，本研究假設疫情期間社群媒體菸品曝光度（媒體影響、社群影響）、正向結果預期（社交誘因、情感誘因、感官誘因）、負向結果預期（健康疑慮與成癮疑慮）與紙菸使用經驗對臺灣青年電子菸使用易感可能存在影響。本研究共蒐集到266位臺灣青年的有效樣本數據，並以結構方程模型檢驗數據有效性及驗證研究假設。結果顯示，僅有情感誘因、感官誘因與使用經驗會影響臺灣青年使用電子菸的易感程度。本研究實證結果將有助於政府菸害防制相關單位，針對臺灣青年未來吸食電子菸的重要影響因素對症下藥，以降低菸害防制成本並確保臺灣青年健康。[[abstract]]While the COVID-19 pandemic prevention, increasingly isolation may result in psychosocial stress, which is a risk factor for e-cigarettes. There is sparse evidence for the intention behind using e-cigarette among young Taiwanese. Based to social learning theory and outcome expectancy, this study provides empirical support for a motivation behind using e-cigarettes by testing the impacted variables derived from the integrated model of smoking on social media (social media and social effect), positive outcome expectation (social, emotion, sensation), negative out-come expectation (harm for health and addiction), and experience with conventional cigarettes. A cross-sectional e-survey was conducted among Taiwanese youths. A total of 266 smokers aged 19-25 years were recruited through an access panel. Findings indicated that in the COVID-19 context, the influences of emotional, sensational stimulations, and experience with conventional cigarettes positively predicts the level of intention for using e-cigarettes. The current study identified the psychosocial mechanisms of intention of e-cigarettes Taiwanese's user during the COVID-19 pandemic, which could be used as an empirical basis for the development of interventions to prevent tobacco. These efforts can help health promotion and reduce the costs of tobacco harm actually outweigh any financial benefits
An interactive greeting system using convolutional neural networks for emotion recognition
No full text[[abstract]]The convolutional neural network (CNN) has been progressively applied in face recognition and various applications. This paper presents an interactive greeting system that combines face identification, emotion recognition, and funny 3D animation. The proposed system recognizes a user by a face-CNN and interacts with the user according to the recognized mood. The animated 3D girl plays a motion-dependent video according to the recognized user’s emotion. First, we employ a Viola-Jones algorithm to segment the areas around the face, eyes, and mouth in a captured image. The face-CNN recognizes a known person. An eye-CNN and a mouth-CNN recognize the emotion. Finally, a 3D animation is played according to the identified emotion. Experimental results show that the proposed interactive greeting system recognizes target persons well, identifies the emotion adequately, and provides users to enjoy funny interaction