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41.
Nehal Elkhoshkhany Samir Marzouk Mohammed El-Sherbiny Heba Ibrahim Bozena Burtan-Gwizdala Mohammed S. Alqahtani Khalid I. Hussien Manuela Reben El Sayed Yousef 《Materials》2022,15(15)
A novel series of glass, consisting of B2O3, Bi2O3, TeO2, and TiO2 (BBTT) containing rare earth oxide RE2O3, where RE is La, Ce, Sm, Er, and Yb, was prepared. We investigated the structural, optical, and gamma attenuation properties of the resultant glass. The optical energy bands, the linear refractive indices, the molar refractions, the metallization criteria, and the optical basicity were all determined for the prepared glass. Furthermore, physical parameters such as the density, the molar volume, the oxygen molar volume, and the oxygen packing density of the prepared glass, were computed. Both the values of density and optical energy of the prepared glass increased in the order of La2O3, Ce2O3, Sm2O3, Er2O3, and then Yb2O3. In addition, the glass doped with Yb2O3 had the lowest refractive index, electronic polarizability, and optical basicity values compared with the other prepared glass. The structures of the prepared glass were investigated by the deconvolution of infrared spectroscopy, which determined that TeO4, TeO3, BO4, BO3, BiO6, and TiO4 units had formed. Furthermore, the structural changes in glass are related to the ratio of the intensity of TeO4/TeO3, depending on the type of rare earth. It is also clarified that the resultant glass samples are good attenuators against low-energy radiation, especially those that modified by Yb2O3, which exhibited superior shielding efficiency at energies of 622, 1170, and 1330 keV. The optical and gamma ray spectroscopy results of the prepared glass show that it is a good candidate for nonlinear optical fibers, laser solid material, and optical shielding protection. 相似文献
42.
Evelyn Tai Li Min Jessica Mani Penny Tevaraj Lakana Kumar Thavaratnam Raja Azmi Mohd Noor Win Mar Salmah Wan Hazabbah Wan Hitam 《国际眼科杂志》2017,17(2):213-216
视神经周围炎(OPN)是指涉及视神经鞘膜的一系列病理性炎症.OPN的经典三联征包括单侧视神经病变伴随疼痛和/或视盘水肿,此病症与其它视神经病变相似,导致诊断延迟和治疗欠佳.2016年1月,我们对发表于Medline和Ovid数据库的关键词为“视神经周围炎”的各种语言的文献进行了检索,共查找到60篇文献,发表于1956-2015年.两位作者(Tai ELM和Tevaraj JMP)分别对论文摘要进行了独立筛选,并筛选出相关文章.本次综述,我们强调OPN的特点,特别是OPN和视神经炎之间的临床差异.虽然大多数OPN的病例是特发性的,但仍需进行调查以排除特异性感染和继发性OPN的炎症原因.MRI是非常重要的检查方法,由于OPN视神经周围炎症的影像学诊断.糖皮质激素治疗可使症状与体征迅速好转,长期口服糖皮质激素并慢速递减可以降低复发的风险. 相似文献
43.
Zafar Ali Shah Khalid Khan Zafar Iqbal Tariq Masood Hassan A. Hemeg Abdur Rauf 《Annals of medicine》2022,54(1):2102
BackgroundPenicillium produces a wide range of structurally diverse metabolites with significant pharmacological impacts in medicine and agriculture. For the first time, a complete metabolome of Penicillium claviforme (P. claviforme) (FBP-DNA-1205) was studied alongside pharmacological research in this study.MethodsThe metabolic profile of P. claviforme fermented on Potato Dextrose Broth (PDB) was investigated in this work. The complete metabolomics studies of fungus were performed using GC-MS and LC-MS-QTOF techniques. An in vitro model was utilised to study the cytotoxic and antioxidant activities, while an in vivo model was employed to investigate the antinociceptive and acute toxicity activities. Molecular Operating Environment (MOE) software was used for molecular docking analysis.ResultsGC-MS study showed the presence of alkanes, fatty acids, esters, azo and alcoholic compounds. Maculosin, obtain, phalluside, quinoline, 4,4’-diaminostilbene, funaltrexamine, amobarbital, and fraxetin were among the secondary metabolites identified using the LC-MS-QTOF technique. The n-hexane fraction of P. claviforme displayed significant cytotoxic activity in vitro, with an LD50 value of 92.22 µgml−1. The antinociceptive effects in vivo were dose-dependent significantly (p < .001). Interestingly, during the 72 h of investigation, no acute toxicity was demonstrated. In addition, a docking study of tentatively identified metabolites against the inflammatory enzyme (COX-2) supported the antinociceptive effect in an in silico model.ConclusionMetabolic profile of P. claviforme shows the presence of biologically relevant compounds in ethyl acetate extract. In addition, P. claviforme exhibits substantial antioxidant and cytotoxic activities in an in vitro model as well as antinociceptive activity in an in vivo model. The antinociceptive action is also supported by a molecular docking study. This research has opened up new possibilities in the disciplines of mycology, agriculture, and pharmaceutics.
Key messages
- The first time explored complete metabolome through GC-MS and LC-MS-QTOF.
- Both in vivo & in vitro pharmacological investigation of P. claviforme.
- In silico molecular docking of LC-MS-QTOF metabolites.
44.
45.
Abdel Bar FM Zaghloul AM Bachawal SV Sylvester PW Ahmad KF El Sayed KA 《Journal of natural products》2008,71(10):1787-1790
Three new 28-norlupane triterpenes, 28-norlup-20(29)-en-3beta-hydroxy-17beta-hydroperoxide (1), 28-norlup-20(29)-en-3beta-hydroxy-17alpha-hydroperoxide (2), and 20 S-17beta,29-epoxy-28-norlupan-3beta-ol (3), were isolated from the leaves of Melaleuca ericifolia along with eight known pentacyclic triterpenes. The structures of the new compounds were elucidated by spectroscopic methods including 1D and 2D NMR spectroscopy and mass spectrometry. The isolated triterpenes were evaluated for antiproliferative activity against the malignant +SA mammary epithelial cell line. 相似文献
46.
Antiosteoporotic chemical constituents from Er-Xian Decoction, a traditional Chinese herbal formula 总被引:2,自引:0,他引:2
AIM OF THE STUDY: Er Xian Decoction (EXD), a traditional Chinese medicine formula, has long been used for the treatment of osteoporosis and menopausal syndrome in China. The present study was designed to investigate the antiosteoporotic constituents of EXD, and evaluate their antiosteoporotic effects in ovariectomized rats. MATERIALS AND METHODS: Osteoblasts in neonatal calvaria cultures and osteoclasts derived from rat marrow cells were used to bioactivity-guided screen the active constituents. The proliferation of osteoblast was assayed by MTT methods. The activity of ALP and TRAP was measured by p- nitrophenyl sodium phosphate assay. The antiosteoporotic effects of icariin (1), anemarsaponin B II (8) and berberine (6) were verified by using OVX rats model. The bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry using the small animal scan mode. The undecalcified longitudinal proximal tibial metaphysical (PTM) sections were cut and stained for the bone histomorphometric analysis. RESULTS: Bioactivity-guided fractionation has led to the successful isolation of antiosteoporotic constituents, i.e., icariin (1), icariside I (2), baohuoside I (3), mangiferin (4), neomangiferin (5), berberine (6), anemarsaponin B (7), anemarsaponin BII (8), anemarsaponin C (9), anemarrhenasaponin I (10), rubiadin-1-methyl ether (11) and obaculactone (12) from EXD. Further study showed that icariin (1), anemarsaponin BII (8) and berberine (6) increased the BMD in ovariectomized rats, and icariin (1) not only increased the bone formation, but also inhibited bone resorption; anemarsaponin BII (8) mainly increased bone formation and berberine (6) only inhibited the bone resorption in ovariectomized rats. CONCLUSION: Our findings demonstrate that multiple ingredients are responsible for antiosteoporotic activity in traditional Chinese medicine formula Er-Xian decoction. 相似文献
47.
BACKGROUND: The incidence of early hypocalcemia in extremely low birthweight (ELBW) infants is unknown because the distribution of serum calcium values in this population is not defined. OBJECTIVE: To determine the range of serum calcium values in ELBW infants during the first 48 h of life and the risks associated with low values. DESIGN/METHODS: Retrospective analysis of all ELBW infants admitted on day 1 of life from April 2004 to October 2006. Demographic variables, therapy, serum calcium (Ca), pH, albumin, and blood ionized Ca were recorded. RESULTS: There were 381 Ca levels obtained from 111 patients. Mean Ca was 6.90 mg/dL (1.73 mmol/L) (5(th)-95(th) percentile: 5.16-8.80). Ca levels rose after 24 h of life. Almost one quarter (23.1%) of the Ca levels were low by current standards. The majority of subjects (59.9%) had at least one hypocalcemic value. CONCLUSIONS: Serum Ca values are lower in ELBW infants and inconsequential. Thus, hypocalcemia should be re-defined for ELBW infants. 相似文献
48.
目的:研究槟榔子(Areca catechu)粗提取物中所含的抗血小板聚集及抑制乙酰胆碱酯酶活性的有效成分及其作用机制。方法:使用70%甲醇水溶液对槟榔子进行粗提取。使用生物发光血小板凝集仪在富血小板血浆中测定槟榔子粗提取物的抗血小板聚集作用,使用分光光度计在试管内测定槟榔子粗提取物对乙酰胆碱酯酶活性的抑制作用。检测槟榔子中的多种化合物以测定槟榔子中抗血小板聚集及抑制乙酰胆碱酯酶活性的有效成分。结果:槟榔子粗提取物能够抑制花生四烯酸、二磷酸腺苷、血小板活化因子、肾上腺素及钙离子载体引起的血小板聚集,尤其对二磷酸腺苷及钙离子载体引起的血小板聚集的抑制最为明显;槟榔子粗提取物能够显著抑制乙酰胆碱酯酶的活性。在所检测的槟榔子所含化合物中,只有儿茶素对肾上腺素引起的血小板聚集有显著的抑制作用,而这种抑制作用显著弱于槟榔子粗提取物,提示槟榔子中的其他成分参与了这种抑制作用;鞣酸、没食子酸、薯蓣皂苷元和异去甲槟榔次碱能够抑制乙酰胆碱酯酶的活性,其中鞣酸的抑制作用强于槟榔子粗提取物。结论:槟榔子中含有抗血小板聚集及抑制乙酰胆碱酯酶活性的有效成分,而发挥这些功效的确切成分有待进一步的研究证实。 相似文献
49.
Severe hypertension sometimes improves with treatment of bradycardia but this phenomenon is under‐reported. Here, an elderly gentleman with complete heart block and a hypertensive emergency was refractory to medical therapies and blood pressure only improved following pacemaker implantation. We discuss the possible mechanisms relating to heart rate and artificial pacing. 相似文献
50.
Sarah Zulkifli Noor Shafina Mohd Nor Siti Hamimah Sheikh Abdul Kadir Norashikin Mohd Ranai Noor Kaslina Mohd Kornain Wan Nor Izzah Wan Mohd Zain Mardiana Abdul Aziz 《Nutrients》2022,14(12)
In this study, we aimed to determine whether a postnatal trans fat diet (TFD) could aggravate prenatal bisphenol A (BPA) exposure effects on offspring’s small intestine and adulthood obesity, due to the relatively sparse findings on how the interaction between these two variables interrupt the small intestinal cells. Twelve pregnant rats were administered with either unspiked drinking water (control; CTL) or BPA-spiked drinking water throughout pregnancy. Twelve weaned pups from each pregnancy group were then given either a normal diet (ND) or TFD from postnatal week (PNW) 3 until PNW14, divided into control offspring on normal diet (CTL-ND), BPA-exposed offspring on normal diet (BPA-ND), control offspring on trans fat diet (CTL-TFD), and BPA offspring on trans fat diet (BPA-TFD) groups. Body weight (BW), waist circumference, and food and water intake were measured weekly in offspring. At PNW14, small intestines were collected for global DNA methylation and histological analyses. Marked differences in BW were observed starting at PNW9 in BPA-TFD (389.5 ± 10.0 g; p < 0.05) relative to CTL-ND (339.0 ± 7.2 g), which persisted until PNW13 (505.0 ± 15.6 g). In contrast, water and food intake between offspring were significantly different (p < 0.01–0.05) at earlier ages only (PNW4–6 and PNW7–9, respectively). Furthermore, substantial differences in the general parameters of the intestinal structures were exclusive to ileum crypt length alone, whereby both BPA-ND (150.5 ± 5.1 μm; p < 0.001), and BPA-TFD (130.3 ± 9.9 μm; p < 0.05) were significantly longer than CTL-ND (96.8 ± 8.9 μm). Moreover, BPA-ND (2.898 ± 0.147%; p < 0.05) demonstrated global small intestinal hypermethylation when compared to CTL-ND and CTL-TFD (1.973 ± 0.232% and 1.913 ± 0.256%, respectively). Prenatal BPA exposure may significantly affect offspring’s physiological parameters and intestinal function. Additionally, our data suggest that there might be compensatory responses to postnatal TFD in the combined BPA prenatal group (BPA-TFD). 相似文献