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排序方式: 共有375条查询结果,搜索用时 15 毫秒
351.
Alireza Khosravi Gilda Kiani Mehr Roya Kelishadi Shahin Shirani Mojgan Gharipour Aliakbar Tavassoli Fatemeh Noori Nizal Sarrafzadegan 《BMC cardiovascular disorders》2010,10(1):1-8
Background
Acute mental stress may contribute to the cardiovascular disease progression via autonomic nervous system controlled negative effects on the endothelium. The joint effects of stress-induced sympathetic or parasympathetic activity and endothelial function on atherosclerosis development have not been investigated. The present study aims to examine the interactive effect of acute mental stress-induced cardiac reactivity/recovery and endothelial function on the prevalence of carotid atherosclerosis.Methods
Participants were 81 healthy young adults aged 24-39 years. Preclinical atherosclerosis was assessed by carotid intima-media thickness (IMT) and endothelial function was measured as flow-mediated dilatation (FMD) using ultrasound techniques. We also measured heart rate, respiratory sinus arrhythmia (RSA), and pre-ejection period (PEP) in response to the mental arithmetic and speech tasks.Results
We found a significant interaction of FMD and cardiac RSA recovery for IMT (p = 0.037), and a significant interaction of FMD and PEP recovery for IMT (p = 0.006). Among participants with low FMD, slower PEP recovery was related to higher IMT. Among individuals with high FMD, slow RSA recovery predicted higher IMT. No significant interactions of FMD and cardiac reactivity for IMT were found.Conclusions
Cardiac recovery plays a role in atherosclerosis development in persons with high and low FMD. The role of sympathetically mediated cardiac activity seems to be more important in those with impaired FMD, and parasympathetically mediated in those with relatively high FMD. The development of endothelial dysfunction may be one possible mechanism linking slow cardiac recovery and atherosclerosis via autonomic nervous system mediated effect. 相似文献352.
Mazzola PG Lam H Kavoosi M Haynes CA Pessoa A Penna TC Wang DI Blankschtein D 《Biotechnology and bioengineering》2006,93(5):998-1004
Green fluorescent protein (GFP) has been proposed as an ideal choice for a protein-based biological indicator for use in the validation of decontamination or disinfection treatments. In this article, we present a potentially scalable and cost-effective way to purify recombinant GFP, produced by fermentation in Escherichia coli, by affinity-enhanced extraction in a two-phase aqueous micellar system. Affinity-enhanced partitioning, which improves the specificity and yield of the target protein by specific bioaffinity interactions, has been demonstrated. A novel affinity tag, family 9 carbohydrate-binding module (CBM9) is fused to GFP, and the resulting fusion protein is affinity-extracted in a decyl beta-D-glucopyranoside (C10G1) two-phase aqueous micellar system. In this system, C10G1 acts as phase forming and as affinity surfactant. We will further demonstrate the implementation of this concept to attain partial recovery of affinity-tagged GFP from a clarified E. coli cell lysate, including the simultaneous removal of other contaminating proteins. The cell lysate was partitioned at three levels of dilution (5x, 10x, and 40x). Irrespective of the dilution level, CBM9-GFP was found to partition preferentially to the micelle-rich phase, with the same partition coefficient value as that found in the absence of the cell lysate. The host cell proteins from the cell lysate were found to partition preferentially to the micelle-poor phase, where they experience less excluded-volume interactions. The demonstration of proof-of-principle of the direct affinity-enhanced extraction of CBM9-GFP from the cell lysate represents an important first step towards developing a cost-effective separation method for GFP, and more generally, for other proteins of interest. 相似文献
353.
Nazila Ariaee Shima Zarei Mojgan Mohamadi Farahzad Jabbari 《Clinical and molecular allergy : CMA》2017,15(1):22
Background
Spontaneous urticaria is a common allergic skin condition affecting 0.5–1% of individuals and may burden on health care expenditure or may be associated with remarkable morbidity.Aim
In this study, we measured the effect of vitamin D supplementation in patients with a diagnosis of CSU. Furthermore, quality of life and cytokine changes were evaluated.Methods
The clinical trial was conducted on 20 patients with idiopathic chronic urticaria. Vitamin D was administered orally for 8 weeks and disease activity was measured pre- and post-treatment using USS and DLQI. On the other hand expressions of IL-17, IL-10, Foxp3, and TGF-β by Real-time RT-PCR were assessed.Results
USS questionnaire showed that severity of idiopathic urticaria after the intervention, which compared with the first day reached a significant 55% reduction. The DLQI quality of life questionnaire 2 months after treatment showed 55% improvement. Along with the significant improvement of clinical symptoms, use of vitamin D increase FOXP3 gene expression and downregulation of IL-10, TGF-B, and FOXP3, IL-17, but these changes were not statistically significant.Limitation
These might happen due to lack of enrolled population in the investigation.Conclusion
Vitamin D can be used along with standard medical care and it’s a safe and cost-effective method for the treatment of chronic urticaria with deficiency of vitamin D.354.
Vardha Ismail Linda G. Zachariassen Annie Godwin Mane Sahakian Sian Ellard Karen L. Stals Emma Baple Kate Tatton Brown Nicola Foulds Gabrielle Wheway Matthew O. Parker Signe M. Lyngby Miriam G. Pedersen Julie Desir Allan Bayat Maria Musgaard Matthew Guille Anders S. Kristensen Diana Baralle 《American journal of human genetics》2022,109(7):1217-1241
355.
Hadi Bayat Saghar Hossienzadeh Eśhagh Pourmaleki Roshanak Ahani 《Preparative biochemistry & biotechnology》2018,48(2):160-164
Monoclonal antibodies (mAbs) have emerged as the most promising category of recombinant proteins due to their high efficiency for the treatment of a wide range of human diseases. The complex nature of mAbs creates a great deal of challenges in both upstream and downstream manufacturing processes. Proportional expression and correct folding and assembly of the light chain and heavy chain are required for efficient production of the mAbs. In this regard, expression vector design has proven to have profound effects on the antibody expression level as well as its stability and quality. Here, we have explored the efficiency of different vector design strategies for the expression of a recombinant IgG1 antibody in Chinese hamster ovary (CHO) cells. The antibody expression level was analyzed in transient expression and stable cell pools followed by expression analysis on single-cell clones. While detectable amounts of antibody were observed in all three systems, dual-promoter single-vector system showed the highest expression level in transient and stable expression as well as the highest productivity among clonal cells. Our results here show the importance of vector design for successful production of whole mAbs in CHO cells. 相似文献
356.
357.
William D Teale Taras Pasternak Cristina Dal Bosco Alexander Dovzhenko Krystyna Kratzat Wolfgang Bildl Manuel Schwrer Thorsten Falk Benadetto Ruperti Jonas V Schaefer Mojgan Shahriari Lena Pilgermayer Xugang Li Florian Lübben Andreas Plückthun Uwe Schulte Klaus Palme 《The EMBO journal》2021,40(1)
The transport of auxin controls the rate, direction and localization of plant growth and development. The course of auxin transport is defined by the polar subcellular localization of the PIN proteins, a family of auxin efflux transporters. However, little is known about the composition and regulation of the PIN protein complex. Here, using blue‐native PAGE and quantitative mass spectrometry, we identify native PIN core transport units as homo‐ and heteromers assembled from PIN1, PIN2, PIN3, PIN4 and PIN7 subunits only. Furthermore, we show that endogenous flavonols stabilize PIN dimers to regulate auxin efflux in the same way as does the auxin transport inhibitor 1‐naphthylphthalamic acid (NPA). This inhibitory mechanism is counteracted both by the natural auxin indole‐3‐acetic acid and by phosphomimetic amino acids introduced into the PIN1 cytoplasmic domain. Our results lend mechanistic insights into an endogenous control mechanism which regulates PIN function and opens the way for a deeper understanding of the protein environment and regulation of the polar auxin transport complex. 相似文献
358.
Talaei Andisheh Mazaheri Somayeh Bayat Elham Bakhshandeh Behnaz Sabzalinejad Masoumeh Damough Shadi Mahboudi Fereidoun Nematollahi Leila Talebkhan Yeganeh 《The protein journal》2021,40(5):786-798
The Protein Journal - With the increasing dominance of monoclonal antibodies (mAbs) in the biopharmaceutical industry and smaller antibody fragments bringing notable advantages over full-length... 相似文献
359.
Neonatal skull anatomy and its evolution have received less attention with respect to the brain anatomy in neuroscience and neuroanatomy studies. Meanwhile, their influence on normal brain development and their impact on the results of functional brain studies have been demonstrated by several researches. Such disesteem is due to the weak appearance of the cranial bones, fontanels and sutures in images acquired by MRI which presents actually the only available aperture for observing the neonatal head volume in details. This paper presents an unprecedented retrospective CT-based study on modeling the neonatal skull and its development during the first weeks of life in a standard space defined by the available neonatal MRI model. We create two neonatal head atlases for the age ranges of 39-40 and 41-42 week's gestational age using symmetric group-wise normalization method. The created atlases allow direct observation of ossification patterns and precise three-dimensional measurement of anatomical features from neonatal skull during development. Development of the neonatal skull has been examined here using nineteen CT scans of neonates with two-week gestational age ranges of 39 to 40 and 41 to 42. Deformation-based morphometry method is applied with the use of Jacobian determinant maps to identify growth patterns and observe ossification during specified time interval. Precise three-dimensional measurements of anterior fontanel size, scalp eliminated head circumference and the area corresponding to the fontanel-sutures were performed by extracting fontanels and sutures. 相似文献
360.