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排序方式: 共有1411条查询结果,搜索用时 15 毫秒
991.
992.
Véronique Masson Laetitia Devy Christine Grignet-Debrus Sarah Bernt Khalid Bajou Silvia Blacher Guy Roland Yawen Chang Timothy Fong Peter Carmeliet Jean-Michel Foidart Agnès Noël 《Biological procedures online》2002,4(1):24-31
Angiogenesis, a key step in many physiological and pathological processes, involves proteolysis of the extracellular matrix.
To study the role of two enzymatic families, serine-proteases and matrix metalloproteases in angiogenesis, we have adapted
to the mouse, the aortic ring assay initially developed in the rat. The use of deficient mice allowed us to demonstrate that
PAI-1 is essential for angiogenesis while the absence of an MMP, MMP-11, did not affect vessel sprouting. We report here that
this model is attractive to elucidate the cellular and molecular mechanisms of angiogenesis, to identify, characterise or
screen “pro- or anti-angiogenic agents that could be used for the treatment of angiogenesis-dependent diseases. Approaches
include using recombinant proteins, synthetic molecules and adenovirus-mediated gene transfer.
Published: October 28, 2002 相似文献
993.
Orth A Belkhir K Britton-Davidian J Boursot P Benazzou T Bonhomme F 《Comptes rendus biologies》2002,325(2):89-97
Using protein loci and DNA markers, we show by a multilocus genetic analysis that certain populations of the two sympatric mouse species Mus musculus domesticus and Mus spretus show clear signs of partial introgression. Given the sterility of F1 males and the known partial genetic incompatibilities between the genomes of the two species, our finding does not invalidate the biological species complex, but allows to think that very limited genetic exchanges remain possible even long after the divergence of taxa. This may have some consequences on the dynamics of certain kinds of invasive or advantageous DNAs like transposable elements or pathogen resistance genes. 相似文献
994.
Zia KM Tabassum S Barkaat-ul-Hasin S Zuber M Jamil T Jamal MA 《International journal of biological macromolecules》2011,48(3):482-487
A series of amino silicone based softeners with different emulsifiers were prepared and adsorbed onto the surfaces of cotton and blends of cotton/polyester fabrics. Factors affecting the performance properties of the finished substrate such as post-treatment with amino functional silicone based softener varying different emulsifiers in their formulations and its concentration on different processed fabrics were studied. Fixation of the amino-functional silicone softener onto/or within the cellulose structure is accompanied by the formation of semi-inter-penetrated network structure thereby enhancing both the extent of crosslinking and networking as well as providing very high softness. The results of the experiments indicate that the amino silicone can form a hydrophobic film on both cotton and blends of cotton/polyester fabrics and its coating reduces the surface roughness significantly. Furthermore, the roughness becomes lesser with an increase in the applied strength of amino silicone based softener. 相似文献
995.
Shi J Qian W Yin X Iqbal K Grundke-Iqbal I Gu X Ding F Gong CX Liu F 《The Journal of biological chemistry》2011,286(16):14639-14648
Hyperphosphorylation and deposition of tau into neurofibrillary tangles is a hallmark of Alzheimer disease (AD). Alternative splicing of tau exon 10 generates tau isoforms containing three or four microtubule binding repeats (3R-tau and 4R-tau), which are equally expressed in adult human brain. Dysregulation of exon 10 causes neurofibrillary degeneration. Here, we report that cyclic AMP-dependent protein kinase, PKA, phosphorylates splicing factor SRSF1, modulates its binding to tau pre-mRNA, and promotes tau exon 10 inclusion in cultured cells and in vivo in rat brain. PKA-Cα, but not PKA-Cβ, interacts with SRSF1 and elevates SRSF1-mediated tau exon 10 inclusion. In AD brain, the decreased level of PKA-Cα correlates with the increased level of 3R-tau. These findings suggest that a down-regulation of PKA dysregulates the alternative splicing of tau exon 10 and contributes to neurofibrillary degeneration in AD by causing an imbalance in 3R-tau and 4R-tau expression. 相似文献
996.
997.
Hirdayesh Anuragi Rajesh Kumar Singhal Yashfa Tanveer Humaira Yasmin Ambati Srijan Alka Bharati Lal Chand Sukumar Taria Kunasekaran Rajarajan Asha Ram Arun Kumar Handa Ayyanadar Arunachalam Khalid Rehman Hakeem Deniz Özbilici Ayman EL Sabagh 《Phyton》2022,91(9):1831-1858
A severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) led novel coronavirus disease (COVID-19) outbreak spread through China has become the biggest global public health challenge today. The virus upon several mutations has led to the resurgence of more infectious and lethal variants infecting over 298 million people with more than 5.46 million deaths worldwide by the end of December, 2021. Though vaccines are available, various preventive measures particularly a high body immunity is still extremely important which determines the likelihood of disease severity and subsequent recovery in the current and future pandemics. This review acknowledges the potentiality of miraculous Moringa oleifera Lam. against recently evolved novel coronavirus and accompanying health complications. Moringa a well-proven super-food, densely packed with an abundant quantity of 92 minerals, several vitamins, 46 antioxidants, and numerous bioactive compounds, thus own a massive therapeutic potential for healing all levels of nutritional deficiencies and poor immunities and cure above 300 diseases. Moringa acts as anti-asthmatic, anti-cancerous, anti-diabetic, anti-inflammatory, hypotensive, hepatic, renal and cardio-protective, and anti-viral in nature. Thus it may reduce the severity of COVID-19 infections and associated serious medical emergencies. In addition, self-isolation at home or the workplace has put people at increased risk of physical and mental sicknesses, which could be simply addressed by integrating this wonderful plant into everyday diet. Furthermore, the immune-modulatory properties and viral inhibiting nature of moringa contribute to reduced risk of COVID-19 infection and quicker recovery from its symptoms. As per the existing pieces of literature, it is a great time to harness the esteemed moringa for safeguarding people from the terrible ongoing COVID-19 situation and other future pandemics. 相似文献
998.
999.
Sengupta Amitabha Wu Qiongli Grundke-Iqbal Inge Iqbal Khalid Singh Toolsee J. 《Molecular and cellular biochemistry》1997,167(1-2):99-105
Tau protein from Alzheimer disease (AD) brain is hyperphosphorylated by both proline-dependent protein kinases (PDPKs) and non-PDPKs. It is presently unclear how PDPKs and non-PDPKs interact in tau hyperphosphorylation. Previously we have shown that non-PDPKs can positively modulate the activity of a PDPK (GSK-3) in tau phosphorylation (Singh et al. (1995) FEBS Lett. 358, 267-272). In this study we have investigated whether (A) non-PDPKs can also modulate the activity of the PDPK, cdk5, (B) a PDPK can modulate the activities of another PDPK, as well as non-PDPKs. We found that, like GSK-3, the activity of cdk5 is stimulated if tau were first prephosphorylated by any of several non-PDPKs (A-kinase, C-kinase, CK-1, CaM-kinase II). Prephosphorylation of tau by cdk5 stimulated both the rate and extent of a subsequent phosphorylation catalyzed by GSK-3. Under these conditions thr 231 phosphorylation was especially enhanced (9-fold). No significant stimulation of phosphorylation was obser ved when the order of these kinases was reversed (i.e. GSK-3 followed by cdk5). By contrast, prephosphorylation of tau by cdk5 served to inhibit subsequent phosphorylation catalyzed by C-kinase and CK-1, but not by A-kinase or CaM-kinase II. Our results suggest that in tau hyperphosphorylation in AD brain, cdk5-catalyzed phosphorylation may serve to up-regulate the activity of GSK-3 and down-regulate the activities of C-kinase and CK-1. (Mol Cell Biochem 167: 99-105, 1997) 相似文献
1000.
Ruojie Zhang Zipei Zhang Taha Kumosani Sawsan Khoja Khalid Omer Abualnaja David Julian McClements 《Food biophysics》2016,11(2):154-164
Nanoemulsion-based delivery systems are finding increasing use in food, pharmaceutical, agrochemical, and personal care applications due to their ability to increase the stability and/or activity of lipophilic functional components. In this study, a low-energy homogenization method (spontaneous emulsification) was used to encapsulate β-carotene in nanoemulsions. The main objective was to optimize lipid phase composition to form stable nanoemulsions that would effectively enhance β-carotene bioavailability. Lipid phase composition was varied by mixing long chain triglycerides (LCT) with medium chain triglycerides (MCT) or flavor oil (orange oil). LCT was added to promote bioaccessibility, whereas MCT or orange oil was added to facilitate nanoemulsion formation. Our hypothesis was that an optimum level of LCT is required to form stable nanoemulsions with good bioaccessibility characteristics. Stable nanoemulsions could be formed at LCT-to-orange oil ratios of 1:1 (d 32 = 109 nm) and at LCT-to-MCT ratios of 1:2 (d 32 = 145 nm). Thus, higher LCT loading capacities and smaller droplet sizes could be obtained using orange oil. The influence of oil composition on the potential gastrointestinal fate of the nanoemulsions was studied using a simulated gastrointestinal tract (GIT) consisting of mouth, stomach, and small intestine phases. The transformation and bioaccessibility of β-carotene in the GIT was highly dependent on lipid phase composition. In particular, β-carotene bioaccessibility increased with increasing LCT level due to greater solubilization in mixed micelles. These results are useful for optimizing the design of nanoemulsion-based delivery systems for encapsulation and release of lipophilic nutraceuticals and pharmaceuticals. 相似文献