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CRMPs (collapsin response mediator proteins)/ULIPs (unc-33-like proteins) are a family of intracytoplasmic proteins that are expressed mainly in the brain. The involvement of CRMP/ULIP members in neuronal differentiation, growth cone motility and axonal collapse has been suggested. We recently found that a member of this family, CRMP3/ULIP4, corresponds to POP66 (paraneoplastic oligodendrocyte protein of 66 kDa), a protein which may be associated with auto-immune induced-neuronal degeneration in paraneoplastic neurological syndromes. However, the physiological functions of these proteins remain to be elucidated. Further studies, including the generation of cell lines and of animals with modified/disrupted CRMP/ULIP gene expression, are necessary to explore the functions of this protein. We have cloned and determined the organization and chromosomal localization of the mouse gene encoding CRMP3/ULIP4. The gene is composed of 14 exons and spans more than 20 kb. We assigned the mouse CRMP3/ULIP4 gene to the distal end of chromosome 7. In mouse brain, in situ hybridization showed that CRMP3/ULIP4 mRNA is expressed mainly in the dentate gyrus of hippocampus, in the granular layers of cerebellum and in the inferior olive of the pons, the nucleus which controls movement and posture, and adjusts the major output of descending motor system.  相似文献   
74.
In platelets, the glycoprotein (GP) Ib-IX receptor complex senses blood shear flow and transmits the mechanical signals into platelets. Recently, we have discovered a juxtamembrane mechanosensory domain (MSD) within the GPIbα subunit of GPIb-IX. Mechanical unfolding of the MSD activates GPIb-IX signaling into platelets, leading to their activation and clearance. Using optical tweezer-based single-molecule force measurement, we herein report a systematic biomechanical characterization of the MSD in its native, full-length receptor complex and a recombinant, unglycosylated MSD in isolation. The native MSD unfolds at a resting rate of 9 × 10?3 s?1. Upon exposure to pulling forces, MSD unfolding accelerates exponentially over a force scale of 2.0 pN. Importantly, the unfolded MSD can refold with or without applied forces. The unstressed refolding rate of MSD is ~17 s?1 and slows exponentially over a force scale of 3.7 pN. Our measurements confirm that the MSD is relatively unstable, with a folding free energy of 7.5 kBT. Because MSD refolding may turn off GPIb-IX’s mechanosensory signals, our results provide a mechanism for the requirement of a continuous pulling force of >15 pN to fully activate GPIb-IX.  相似文献   
75.
Biomanufacturing exhibits inherent variability that can lead to variation in performance attributes and batch failure. To help ensure process consistency and product quality the development of predictive models and integrated control strategies is a promising approach. In this study, a feedback controller was developed to limit excessive lactate production, a widespread metabolic phenomenon that is negatively associated with culture performance and product quality. The controller was developed by applying machine learning strategies to historical process development data, resulting in a forecast model that could identify whether a run would result in lactate consumption or accumulation. In addition, this exercise identified a correlation between increased amino acid consumption and low observed lactate production leading to the mechanistic hypothesis that there is a deficiency in the link between glycolysis and the tricarboxylic acid cycle. Using the correlative process parameters to build mechanistic insight and applying this to predictive models of lactate concentration, a dynamic model predictive controller (MPC) for lactate was designed. This MPC was implemented experimentally on a process known to exhibit high lactate accumulation and successfully drove the cell cultures towards a lactate consuming state. In addition, an increase in specific titer productivity was observed when compared with non-MPC controlled reactors.  相似文献   
76.

BACKGROUND

There is a high and rising rate of immune-mediated diseases in the Western world. Immigrants from South Asia have been reported to be at higher risk upon arrival to the West. We determined the risk of immune-mediated diseases in South Asian and other immigrants to Ontario, Canada, and their Ontario-born children.

METHODS

Population-based cohorts of patients with asthma, type 1 diabetes (T1DM), type 2 diabetes (T2DM), and inflammatory bowel disease (IBD) were derived from health administrative data. We determined the standardized incidence, and the adjusted risk of these diseases in immigrants from South Asia, immigrants from other regions, compared with non-immigrant residents of Ontario. The risk of these diseases in the Ontario-born children of immigrants were compared to the children of non-immigrants.

RESULTS

Compared to non-immigrants, adults from South Asia had higher risk of asthma (IRR 1.56, 95%CI 1.51-1.61) and T2DM (IRR 2.59, 95%CI 2.53-2.65). Adults from South Asia had lower incidence of IBD than non-immigrants (IRR 0.32, 95%CI 0.22-0.49), as did immigrants from other regions (IRR 0.29, 95%CI 0.20-0.42). Compared to non-immigrant children, the incidence of asthma (IRR 0.66, 95%CI 0.62-0.71) and IBD (IRR 0.47, 95%CI 0.33-0.67) was low amongst immigrant children from South Asia. However, the risk in Ontario-born children of South Asian immigrants relative to the children of non-immigrants was higher for asthma (IRR 1.75, 95%CI 1.69-1.81) and less attenuated for IBD (IRR 0.90, 95%CI 0.65-1.22).

CONCLUSION

Early-life environmental exposures may trigger a genetic predisposition to the development of asthma and IBD in South Asian immigrants and their Canada-born children.  相似文献   
77.

Background

The aim of this study was to understand online public perceptions of the debate surrounding the choice of annual influenza vaccinations or wearing masks as a condition of employment for healthcare workers, such as the one enacted in British Columbia in August 2012.

Methods

Four national and 82 local (British Columbia) Canadian online news sites were searched for articles posted between August 2012 and May 2013 containing the words “healthcare workers” and “mandatory influenza vaccinations/immunizations” or “mandatory flu shots and healthcare workers.” We included articles from sources that predominantly concerned our topic of interest and that generated reader comments. Two researchers coded the unedited comments using thematic analysis, categorizing codes to allow themes to emerge. In addition to themes, the comments were categorized by: 1) sentiment towards influenza vaccines; 2) support for mandatory vaccination policies; 3) citing of reference materials or statistics; 4) self-identified health-care worker status; and 5) sharing of a personal story.

Results

1163 comments made by 648 commenters responding to 36 articles were analyzed. Popular themes included concerns about freedom of choice, vaccine effectiveness, patient safety, and distrust in government, public health, and the pharmaceutical industry. Almost half (48%) of commenters expressed a negative sentiment toward the influenza vaccine, 28% were positive, 20% were neutral, and 4% expressed mixed sentiment. Of those who commented on the policy, 75% did not support the condition to work policy, while 25% were in favour. Of the commenters, 11% self-identified as healthcare workers, 13% shared personal stories, and 18% cited a reference or statistic.

Interpretation

The perception of the influenza vaccine in the comment sections of online news sites is fairly poor. Public health agencies should consider including online forums, comment sections, and social media sites as part of their communication channels to correct misinformation regarding the benefits of HCW influenza immunization and the effectiveness of the vaccine.  相似文献   
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The ability of HDL to support macrophage cholesterol efflux is an integral part of its atheroprotective action. Augmenting this ability, especially when HDL cholesterol efflux capacity from macrophages is poor, represents a promising therapeutic strategy. One approach to enhancing macrophage cholesterol efflux is infusing blood with HDL mimics. Previously, we reported the synthesis of a functional mimic of HDL (fmHDL) that consists of a gold nanoparticle template, a phospholipid bilayer, and apo A-I. In this work, we characterize the ability of fmHDL to support the well-established pathways of cellular cholesterol efflux from model cell lines and primary macrophages. fmHDL received cell cholesterol by unmediated (aqueous) and ABCG1- and scavenger receptor class B type I (SR-BI)-mediated diffusion. Furthermore, the fmHDL holoparticle accepted cholesterol and phospholipid by the ABCA1 pathway. These results demonstrate that fmHDL supports all the cholesterol efflux pathways available to native HDL and thus, represents a promising infusible therapeutic for enhancing macrophage cholesterol efflux. fmHDL accepts cholesterol from cells by all known pathways of cholesterol efflux: unmediated, ABCG1- and SR-BI-mediated diffusion, and through ABCA1.  相似文献   
80.
Only single cells in the carrier fish species Carassius carassius (Linnaeus, 1758) for koi herpesvirus (KHV) are infected in contrast to large numbers in the susceptible species common carp Cyprinus carpio (Linnaeus 1758). Several species of the family Cyprinidae have been described as virus carrier species, showing no clinical signs of a KHV disease but able to transmit the virus to other susceptible fish. In this study, 72 common carp Cyprinus carpio (Linnaeus, 1758), 36 tench Tinca tinca (Linnaeus, 1758), 36 crucian carp Carassius carassius (Linnaeus, 1758) and 36 common roach Rutilus rutilus (Linnaeus, 1758) were experimentally infected with KHV (isolate “Israel”) by immersion and kept at 20°C. The fish were euthanized at 12 timepoints over a period of 90 days and virus DNA was quantified in tissues by a real‐time TaqMan PCR. Whereas KHV‐DNA was found in Cyprinus carpio for up to 90 days, the virus DNA was detectable only in single individuals of Rutilus rutilus, Tinca tinca and Carassius carassius for up to 25 days after experimental virus exposure. Tissue samples of Cyprinus carpio and Carassius carassius were screened by in‐situ hybridization. Positive signals were found in various organs of the common carp tested crucian carp. In the latter species a much smaller number of virus‐positive stained cells was detected compared to the infected carp.  相似文献   
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