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991.
Abdullah Alghasham Abdulaziz AM Al Salloom Ahmed SS Alghamadi 《Nucleosides, nucleotides & nucleic acids》2015,34(1):56-68
Present study probes the role of peroxynitrite (ONOO-)-modified thymidine-5′-monophosphate (TMP) in SLE patients with different disease activity scores according to the SLE Disease Activity Index (SLEDAI). Serum analysis showed significant increased number of subjects positive for anti-ONOO--TMP-protein antibodies in SLE patients with different SLEDAI scores. Interestingly, the levels of these antibodies were significantly higher among SLE patients, whose SLEDAI scores were ≥20. In addition, a significant correlation was observed between the levels of anti-ONOO--TMP-protein antibodies and the SLEDAI score (r = 0.595, p < 0.0001). In short, this study shows a positive association between anti-ONOO--TMP-protein antibodies and SLEDAI. The stronger response observed in patients with higher SLEDAI scores suggests that anti-ONOO--TMP-protein antibodies may be useful in evaluating the progression of SLE and in elucidating the mechanisms of disease pathogenesis. 相似文献
992.
Chen N Liow SL Abdullah RB Embong WK Yip WY Tan LG Tong GQ Ng SC 《Zygote (Cambridge, England)》2007,15(1):25-33
Somatic cell nuclear transfer (SCNT) is not successful so far in non-human primates. The objective of this study was to investigate the effects of stimulation cycles (first and repeat) on oocyte retrieval and in vitro maturation (IVM) and to evaluate the effects of stimulation cycles and donor cell type (cumulus and fetal skin fibroblasts) on efficiency of SCNT with transported IVM oocytes. In this study, 369 immature oocytes were collected laparoscopically at 24 h following human chorionic gonadotrophin (hCG) treatment from 12 cynomolgus macaque (Macaca fascicularis) in 24 stimulation cycles, and shipped in pre-equilibrated IVM medium for a 5 h journey, placed in a dry portable incubator (37 degrees C) without CO(2) supplement. A total of 70.6% (247/350) of immature oocytes reached metaphase II (MII) stage at 36 h after hCG administration, MII spindle could be seen clearly in 80.6% (104/129) of matured IVM oocytes under polarized microscopy. A total of 50.0% (37/74) of reconstructive SCNT embryos cleaved after activation; after cleavage, 37.8% (14/37) developed to the 8-cell stage and 8.1% (3/37) developed to morula, but unfortunately none developed to the blastocyst stage. Many more oocytes could be retrieved per cycle from monkeys in the first cycle than in repeated cycles (19.1 vs. 11.7, p < 0.05). There were no significant differences in the maturation rate (70.0 vs. 71.4%, p > 0.05) and MII spindle rate under polarized microscopy (76.4 vs. 86.0%, p > 0.05) between the first and repeat cycles. There were also no significant differences in the cleavage rate, and the 4-cell, 8-cell and morula development rate of SCNT embryos between the first and repeat cycles. When fibroblast cells and cumulus cells were used as the donor cells for SCNT, first cleavage rate was not significantly different, but 4-cell (50.0 vs. 88.9%, p < 0.05) and 8-cell (0 vs. 51.9%, p < 0.01) development rate were significantly lower for the former. In conclusion, the number of stimulation cycles has a significant effect on oocyte retrieval, but has no effect on maturation and SCNT embryo development; however, different donor cell types (cumulus and fibroblast) resulted in different developmental potentials of SCNT embryos. 相似文献
993.
Abdullah Al-Ghazi 《Revue de Micropaléontologie》2007,50(1):59
Well-preserved Early Devonian continental and sparse marine palynomorph assemblages recovered from an exploration borehole located in northern Saudi Arabia are reported here and add to the understanding of Arabian Devonian stratigraphy. The units examined are the conventionally cored lower Murayr, upper Hammamiyat and Sha’iba Members of the Jauf Formation. A comparison with data sets from elsewhere on the Arabian Plate suggests that the units examined are Emsian in age. The age of the Murayr and Hammamiyat boundary interval is revised, based on the occurrence of Dibolisporites eifeliensis in northern Saudi Arabia, and placed in the Rhabdosporites minutus (Min) Interval Zone of the Emphanisporites foveolatus-Verrucosisporites dubia (FD) Oppel Zone. A new miospore, Apiculiretusispora densa with distinctive interradial thickenings, is described. 相似文献
994.
The nature of the hydration of proteins and the subsequent implications for functionality is a matter of importance in both pharmaceutical and food applications. Most published studies rely on the use of one technique and attempt to characterize the system. Few studies have used combinations of techniques. In this paper we report on the use of infrared, dielectric, and calorimetric methods to examine the hydration process of wheat gluten. This has been the subject of considerable study by other techniques and has been well characterized by our group. Results show that in both the infrared and dielectric measurements there is a change in behavior at about 35% water content. This is also the water content below which lowering the temperature of the sample does not result in ice formation. We suggest that at this water content the protein amide groups are fully hydrated, and beyond this point addition of water results in protein dilution rather than further hydration. 相似文献
995.
An arginine-glycine-aspartic acid (RGD) containing model peptide was conjugated to the surface of poly(ethylene oxide)-block-poly(epsilon-caprolactone) (PEO-b-PCL) micelles as a ligand that can recognize adhesion molecules overexpressed on the surface of metastatic cancer cells, that is, integrins, and that can enhance the micellar delivery of encapsulated hydrophobic drug into a tumor cell. Toward this goal, PEO-b-PCL copolymers bearing acetal groups on the PEO end were synthesized, characterized, and assembled to polymeric micelles. The acetal group on the surface of the PEO-b-PCL micelles was converted to reactive aldehyde under acidic condition at room temperature. An RGD-containing linear peptide, GRGDS, was conjugated on the surface of the aldehyde-decorated PEO-b-PCL micelles by incubation at room temperature. A hydrophobic fluorescent probe, that is, DiI, was physically loaded in prepared polymeric micelles to imitate hydrophobic drugs loaded in micellar carrier. The cellular uptake of DiI loaded GRGDS-modified micelles by melanoma B16-F10 cells was investigated at 4 and 37 degrees C by fluorescent spectroscopy and confocal microscopy techniques and was compared to the uptake of DiI loaded valine-PEO-b-PCL micelles (as the irrelevant ligand decorated micelles) and free DiI. GRGDS conjugation to polymeric micelles significantly facilitated the cellular uptake of encapsulated hydrophobic DiI most probably by intergrin-mediated cell attachment and endocytosis. The results indicate that acetal-terminated PEO-b-PCL micelles are amenable for introducing targeting moieties on the surface of polymeric micelles and that RGD-peptide conjugated PEO-b-PCL micelles are promising ligand-targeted carriers for enhanced drug delivery to metastatic tumor cells. 相似文献
996.
Quan Yu van den Ende Bert Gerrits Shi Dongmei Prenafeta-Boldú Francesc X. Liu Zuoyi Al-Hatmi Abdullah M. S. Ahmed Sarah A. Verweij Paul E. Kang Yingqian de Hoog Sybren 《Mycopathologia》2019,184(5):653-660
Mycopathologia - The prevalence of black fungi in the order Chaetothyriales has often been underestimated due to the difficulty of their isolation. In this study, three methods which are often used... 相似文献
997.
Albegali Abdullah Abdo Shahzad Muhammad Mahmood Saqib Ullah Muhammad Ikram 《Molecular biology reports》2019,46(6):6065-6070
Molecular Biology Reports - Insulin resistance (IR), a pathological condition of type 2 diabetes mellitus (T2DM) is characterized by an inability of body’s tissue to respond the secreted or... 相似文献
998.
999.
1000.
Abdullah Asmaa Hayashi Yoshitaka Morimura Naoko Kumar Akhilesh Ikenaka Kazuhiro Togayachi Akira Narimatsu Hisashi Hitoshi Seiji 《Neurochemical research》2022,47(9):2793-2804
Neurochemical Research - α1,3-Fucosyltransferase 9 (Fut9) is responsible for the synthesis of Lewis X [LeX, Galβ1-4(Fucα1-3)GlcNAc] carbohydrate epitope, a marker for pluripotent or... 相似文献