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201.
Chromosome congression and segregation have been widely known to be coordinated by the function of the dynamic spindle microtubules. But recent work suggests that oocytes may employ a unique actin-dependent mechanism of chromosome delivery to the spindle. 相似文献
202.
203.
RH Fahmy 《AAPS PharmSciTech》2012,13(3):990-1004
Multiparticulate floating drug delivery systems have proven potential as controlled-release gastroretentive drug delivery systems that avoid the "all or none" gastric emptying nature of single-unit floating dosage forms. An objective of the presence investigation was to develop calcium silicate (CaSi)/calcium alginate (Ca-Alg)/hydroxypropyl methylcellulose (HPMC) mucoadhesive-floating beads that provide time- and site-specific drug release of alfuzosin hydrochloride (Alf). Beads were prepared by simultaneous internal and external gelation method utilizing 3(2) factorial design as an experimental design; with two main factors evaluated for their influence on the prepared beads; the concentration of CaSi as floating aid (X (1)) and the percentage of HPMC as viscosity enhancer and mucoadhesive polymer (X (2)), each of them was tested in three levels. Developed formulations were evaluated for yield, entrapment efficiency, particle size, surface topography, and buoyancy. Differential scanning calorimetry, Fourier transform infrared spectroscopy, in vitro drug release, as well as in vitro mucoadhesion using rat stomach mucosal membrane were also conducted. Percentage yield and entrapment efficiency ranged from 57.03% to 78.51% and from 49.78% to 83.26%, respectively. Statistical analysis using ANOVA proved that increasing the concentration of either CaSi or HPMC significantly increased the beads yield. Both CaSi and HPMC concentrations were found to significantly affect Alf release from the beads. Additionally, higher CaSi concentration significantly increased the beads diameter while HPMC concentration showed significant positive effect on the beads mucoadhesive properties. CaSi/Ca-Alg/HPMC beads represent simple floating-mucoadhesive gastroretentive system that could be useful in chronopharmacotherapy of benign prostatic hyperplasia. 相似文献
204.
Rania Ben-Saad Walid Ben-Ramdhan Nabil Zouari Jalel Azaza Delphine Mieulet Emmanuel Guiderdoni Radhouane Ellouz Afif Hassairi 《Molecular breeding : new strategies in plant improvement》2012,30(1):521-533
We have recently isolated the AlSAP (stress-associated protein) gene from the halophyte grass Aeluropus littoralis and demonstrated that AlSAP expression improves tolerance to continuous salt and drought stresses in transgenic tobacco. To extend these findings to an important crop, we generated marker-free transgenic durum wheat plants of the commercial cv. Karim expressing the AlSAP gene. The integration and expression of AlSAP in T3 homozygous plants were ascertained by Southern, Northern and Western blotting respectively. AlSAP wheat lines exhibited improved germination rates and biomass production under severe salinity and osmotic stress conditions. Following a long-term salt or drought stress greenhouse trial, AlSAP lines produced normally filled grains whereas wild-type (WT) plants either died at the vegetative stage under salt stress or showed markedly reduced grain filling under drought stress. Measurements of the RWC (relative water content) and endogenous Na+ and K+ levels in leaves of AlSAP plants, showed a lower water loss rate and a higher Na+ accumulation in senescent-basal leaves, respectively, compared to those of WT plants. Taken together, these results extend to cereals the high potential of the AlSAP gene for engineering effective drought and salt tolerance. 相似文献
205.
Ischemic preconditioning (IPC), comprising exposure to sub-lethal short term ischemic events, has been shown to exert adaptive
responses in many organs including the brain, thus guarding against exacerbations of ischemia reperfusion (IR). However, the
mechanisms involved in the early phase of such a protection remain elusive; hence, the present study aimed to investigate
the modulatory effect of preconditioning against IR induced injury on infarct size, free radicals, inflammatory/anti-inflammatory
markers, caspase-3 and heat shock protein (HSP)70 in the rat hippocampus. To this end, male Wistar rats were divided into
3 groups, (1) sham operated (SO) control; (2) IPC, animals were subject to 3 episodes of ischemia (5 min) followed by reperfusion
(10 min), afterwards rats underwent ischemia (15 min) followed by reperfusion (60 min); (3) IR animals were subjected to 15 min
global ischemia followed by 60 min reperfusion. IR produced cerebral infarction accompanied by an imbalance in the hippocampal
redox status, neutrophil infiltration, elevation in tumor necrosis factor (TNF)-α and prostaglandin (PG)E2, besides reduction in interleukin (IL)-10 and nitric oxide (NO) levels. IPC reverted all changes except for PGE2; however, neither HSP70 nor caspase-3 expression was altered following IR or IPC. The current study points thus towards the
activation of the antioxidant system, anti-inflammatory pathway, as well as NO in the early phase of preconditioning protection. 相似文献
206.
Rania A. El-Farrash Mohammed S. El-Shimy Sameh Tawfik Ahmed S. Nada Dalia A. D. Salem Mohammed S. M. Gallo 《Free radical research》2019,53(2):179-186
In order to evaluate the effect of different types of phototherapy on oxidant/antioxidant status in hyperbilirubinemic neonates, an interventional randomized control trial was conducted on 120 neonates ≥35 weeks’ gestational age with indirect hyperbilirubinemia reaching phototherapy level. This study is registered with ClinicalTrials.gov as NCT03074292. Neonates were assigned to three groups; 40 neonates received conventional phototherapy, 40 received intensive phototherapy and 40 received blue light-emitting diodes (LED) phototherapy. Complete blood count (CBC), total serum bilirubin (TSB), total antioxidant capacity (TAC), malondialdehyde (MDA), nitric oxide (NO), copper (Cu), zinc (Zn), and iron (Fe) levels were measured before and 24?hours after phototherapy. TSB decreased postphototherapy in all three groups (p < .05 for all), with significantly lower levels following intensive and LED phototherapy compared to conventional phototherapy (p < .05 for both). TAC decreased postphototherapy in the three groups (p < .05 for all). MDA and NO increased postphototherapy (p < .05 for all), with the intensive phototherapy group having the highest levels followed by the conventional while LED phototherapy group showed the lowest levels in comparison to the other groups (p < .05). Cu, Zn and Fe increased postphototherapy in all three groups (p < .05 for all). Positive correlations were found between postphototherapy TSB with TAC, Cu and Zn (p < .05) and negative correlations with MDA, NO and Fe (p < .05) among neonates of the 3 studied groups. In conclusion, different photo therapies have an impact on oxidant/antioxidant balance and are associated with increased oxidative stress markers with the LED phototherapy being the safest. 相似文献
207.
Zouhir Abdelmajid Jemli Sonia Omrani Rania kthiri Amani Jridi Taoufik sebei Khaled 《International journal of peptide research and therapeutics》2021,27(2):1253-1263
International Journal of Peptide Research and Therapeutics - During the last decade there has been an alarming increase in the appearance of antibiotic-resistant bacteria. The drug-resistant... 相似文献
208.
Tomoyuki Kino Toshiki Tomori Rania Abutarboush Paola Castri Ye Chen Frederick A. Lenz Richard M. McCarron Maria Spatz 《Biochemistry and Biophysics Reports》2016
N-arachidonoyl-l-serine (ARA-S) is an endogenous lipid, chemically related to the endocannabinoid, N-arachidonoyl ethanolamine (i.e., anandamide) and with similar physiologic and pathophysiologic functions. Reports indicate that ARA-S possesses vasoactive and neuroprotective properties resembling those of cannabinoids. However, in contrast to cannabinoids, ARA-S binds weakly to its known classical receptors, CB1 and CB2, and is therefore considered to be a ‘cannabinoid-like’ substance. The originally described ARA-S induced-endothelial-dependent vasorelaxation was not abrogated by CB1, CB2 receptor antagonists or TRPV1 competitive inhibitor. The present report demonstrates that ARA-S enhances the fluorescence staining of both cannabinoid receptors (CB1 and CB2) in human brain endothelial cells (HBEC). This reaction is specific since it was reduced by respective selective receptor antagonist (SR141716A and SR141728A). ARA-S alone or in the presence of ET-1 was shown to alter the cytoskeleton (actin). Both ARA-S stimulated phosphorylation of various kinases (MAPK, Akt, JNK and c-JUN) and alteration of cytoskeleton are mediated via CB1, CB2 and TRPV1 receptors. The findings also showed the involvement of Rho/Rock and PI3/Akt/NO pathways in the ARA-S-induced phosphorylation of kinases and actin reorganization in HBEC. All of the above mentioned ARA-S-induced effects were reduced by the treatment with LY294002 (inhibitor of PI3/Akt kinase), except MAPK kinase. In addition, MAPK, JNK, c-JUN phosphorylation were inhibited by H1152 (inhibitor of Rho/ROCK kinase), except Akt kinase. Furthermore, PI3/Akt pathway was inhibited by pretreatment with l-NAME (inhibitor of NOS). The findings suggest that ARA-S is a modulator of Rho kinase and may play a critical role in the regulation of its activity and subsequent effects on the cytoskeleton and its role in supporting essential cell functions like vasodilation, proliferation and movement. 相似文献
209.
Cecília Seixas Soo Young Choi Noemi Polgar Nicole L. Umberger Michael P. East Xiaofeng Zuo Hugo Moreiras Rania Ghossoub Alexandre Benmerah Richard A. Kahn Ben Fogelgren Tamara Caspary Joshua H. Lipschutz Duarte C. Barral 《Molecular biology of the cell》2016,27(2):308-320
Arl13b belongs to the ADP-ribosylation factor family within the Ras superfamily of regulatory GTPases. Mutations in Arl13b cause Joubert syndrome, which is characterized by congenital cerebellar ataxia, hypotonia, oculomotor apraxia, and mental retardation. Arl13b is highly enriched in cilia and is required for ciliogenesis in multiple organs. Nevertheless, the precise role of Arl13b remains elusive. Here we report that the exocyst subunits Sec8, Exo70, and Sec5 bind preferentially to the GTP-bound form of Arl13b, consistent with the exocyst being an effector of Arl13b. Moreover, we show that Arl13b binds directly to Sec8 and Sec5. In zebrafish, depletion of arl13b or the exocyst subunit sec10 causes phenotypes characteristic of defective cilia, such as curly tail up, edema, and abnormal pronephric kidney development. We explored this further and found a synergistic genetic interaction between arl13b and sec10 morphants in cilia-dependent phenotypes. Through conditional deletion of Arl13b or Sec10 in mice, we found kidney cysts and decreased ciliogenesis in cells surrounding the cysts. Moreover, we observed a decrease in Arl13b expression in the kidneys from Sec10 conditional knockout mice. Taken together, our results indicate that Arl13b and the exocyst function together in the same pathway leading to functional cilia. 相似文献
210.
Gihan M. Tawfeek Hala S. Elwakil Nabil S. Awad Laila El-Hoseiny Hala S. Thabet Rania M. Sarhan Samar K. Darweesh Wagida A. Anwar 《The Korean journal of parasitology》2009,47(3):259-264
Genetic polymorphisms of encoding antigen B2 gene (AgB2) in Echinococcus granulosus were studied using PCR-RFLP and DNA sequencing among 20 Egyptian isolates. Five isolates from different host origins (humans, camels, pigs, and sheep) were collected and used. All examined isolates of each host group gave very similar patterns of PCR-RFLP after restriction enzyme digestion with AluI, with the gene size of approximately 140 bp and 240 bp for sheep and human isolates, and approximately 150 bp and 250 bp for pig and camel isolates. No digestion pattern was obtained after incubation of all studied isolates with EcoRI. These results reveal high intra-group homogeneity. DNA sequence analysis highlighted that human infecting strain showed 100% identity with respect to sheep infecting isolate, 96% and 99% with pig and camel infecting isolates, respectively. 相似文献