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Functional implications of B lymphocytes in the development of rheumatoid arthritis
María-Carolina Páez Leal,Luis Miguel Gómez,Juan-Manuel Anaya
MedUNAB , 2006,
Abstract: B cells play a key role in regulating the immune system by producingantibodies, acting as antigen-presenting cells, providing support toother mononuclear cells, and contributing directly to inflammatorypathways. Accumulating evidence indicates that there is a disruptionof these regulated processes in the pathogenesis of autoimmunediseases, including rheumatoid arthritis (RA). In RA there is a chronic inflammation in the affected joints leading to the development of ectopic germinal centers. A micro-environment is established which supports B cell activation and differentiation. Plasma cells may develop which secrete autoantibodies of high affinity directly into the synovial tissue. As a result, antigen/antibody complex formation, the activation of the complement cascade and the stimulation of macrophages may contribute to the destruction of joints. B cells also play a pivotal role in the activation of synovial T cells and the induction of cytokine secretion. Finally, the success of B cell depletion therapy by using monoclonal antibodies against CD20 further emphasized the importance of B cells in the pathogenesis of RA
Sleep in brain development
PEIRANO,PATRICIO D; ALGARíN,CECILIA R;
Biological Research , 2007, DOI: 10.4067/S0716-97602007000500008
Abstract: with the discovery of rapid eye movement (rem) sleep, sleep was no longer considered a homogeneous state of passive rest for the brain. on the contrary, sleep, and especially rem sleep, appeared as an active condition of intense cerebral activity. the fact that we get large amounts of sleep in early life suggested that sleep may play a role in brain maturation. this idea has been investigated for many years through a large number of animal and human studies, but evidence remains fragmented. the hypothesis proposed was that rem sleep would provide an endogenous source of activation, possibly critical for structural maturation of the central nervous system. this proposal led to a series of experiments looking at the role of rem sleep in brain development. in particular, the influence of sleep in developing the visual system has been highlighted. more recently, non-rem (nrem) sleep state has become a major focus of attention. the current data underscore the importance of both rem sleep and nrem sleep states in normal synaptic development and lend support to their functional roles in brain maturation. both sleep states appear to be important for neuronal development, but the corresponding contribution is likely to be different
Sleep in brain development
PATRICIO D PEIRANO,CECILIA R ALGARíN
Biological Research , 2007,
Abstract: With the discovery of rapid eye movement (REM) sleep, sleep was no longer considered a homogeneous state of passive rest for the brain. On the contrary, sleep, and especially REM sleep, appeared as an active condition of intense cerebral activity. The fact that we get large amounts of sleep in early life suggested that sleep may play a role in brain maturation. This idea has been investigated for many years through a large number of animal and human studies, but evidence remains fragmented. The hypothesis proposed was that REM sleep would provide an endogenous source of activation, possibly critical for structural maturation of the central nervous system. This proposal led to a series of experiments looking at the role of REM sleep in brain development. In particular, the influence of sleep in developing the visual system has been highlighted. More recently, non-REM (NREM) sleep state has become a major focus of attention. The current data underscore the importance of both REM sleep and NREM sleep states in normal synaptic development and lend support to their functional roles in brain maturation. Both sleep states appear to be important for neuronal development, but the corresponding contribution is likely to be different
Development of an Online Sleep Diary for Physician and Patient Use  [cached]
Jacqueline Blake,Don Kerr
Knowledge Management & E-Learning : an International Journal , 2010,
Abstract: This paper describes the development of an electronic sleep diary and outlines its advantages over the traditional paper based approach still used by many sleep centres throughout the world. A sleep diary is a record of sleep details filled in by a patient normally over a period of two weeks. This information is then used by a physician as a diagnostic tool for identify sleep disorders in the patient. The development method used was convergent interviews with sleep specialists in order to establish initial requirements. This was followed by a rapid prototyping approach in order to produce the final specification. This paper concludes that an online sleep diary is a low cost, viable alternative offering benefits to both patients and physicians. The benefits to patients include the ability to perform functional analysis of their own sleep habits (referred to as sleep hygiene) and to determine factors affecting their sleep patterns. This knowledge leads to greater patient understanding of their circumstances and can lead to a potential increase in patient, physician collaboration. The physician gains access to timely accessible patient information as well as to an evidence database that will allow for greater analysis of sleep disorders throughout the general public over time.
The Implications of Complicated Grief for the Sleep
Thiago De Almeida
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1104572
Abstract:
Complicated grief is a situation in which the individual, faced with a loss, does not present adaptive responses in dealing with this stimulus. This study aimed to understand how Complicated Grief may be a factor that may interfere in the sleep process, seeking possible relationships between these two themes. Thus, a review of the literature dealing with complicated grief and the sleep process has been done. It can be observed in cases of Complicated Grief, individuals tended to present problems related to sleep, either alterations in the amount of sleeping hours or greater difficulty in getting to sleep. Further researches are needed to relate Complicated Grief to the sleep process since those are two aspects that can be related.
Functional Relationship between Skull Form and Feeding Mechanics in Sphenodon, and Implications for Diapsid Skull Development  [PDF]
Neil Curtis, Marc E. H. Jones, Junfen Shi, Paul O'Higgins, Susan E. Evans, Michael J. Fagan
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0029804
Abstract: The vertebrate skull evolved to protect the brain and sense organs, but with the appearance of jaws and associated forces there was a remarkable structural diversification. This suggests that the evolution of skull form may be linked to these forces, but an important area of debate is whether bone in the skull is minimised with respect to these forces, or whether skulls are mechanically “over-designed” and constrained by phylogeny and development. Mechanical analysis of diapsid reptile skulls could shed light on this longstanding debate. Compared to those of mammals, the skulls of many extant and extinct diapsids comprise an open framework of fenestrae (window-like openings) separated by bony struts (e.g., lizards, tuatara, dinosaurs and crocodiles), a cranial form thought to be strongly linked to feeding forces. We investigated this link by utilising the powerful engineering approach of multibody dynamics analysis to predict the physiological forces acting on the skull of the diapsid reptile Sphenodon. We then ran a series of structural finite element analyses to assess the correlation between bone strain and skull form. With comprehensive loading we found that the distribution of peak von Mises strains was particularly uniform throughout the skull, although specific regions were dominated by tensile strains while others were dominated by compressive strains. Our analyses suggest that the frame-like skulls of diapsid reptiles are probably optimally formed (mechanically ideal: sufficient strength with the minimal amount of bone) with respect to functional forces; they are efficient in terms of having minimal bone volume, minimal weight, and also minimal energy demands in maintenance.
Fetal Functional Brain Age Assessed from Universal Developmental Indices Obtained from Neuro-Vegetative Activity Patterns  [PDF]
Dirk Hoyer, Florian Tetschke, Susan Jaekel, Samuel Nowack, Otto W. Witte, Ekkehard Schleu?ner, Uwe Schneider
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0074431
Abstract: Fetal brain development involves the development of the neuro-vegetative (autonomic) control that is mediated by the autonomic nervous system (ANS). Disturbances of the fetal brain development have implications for diseases in later postnatal life. In that context, the fetal functional brain age can be altered. Universal principles of developmental biology applied to patterns of autonomic control may allow a functional age assessment. The work aims at the development of a fetal autonomic brain age score (fABAS) based on heart rate patterns. We analysed n = 113 recordings in quiet sleep, n = 286 in active sleep, and n = 29 in active awakeness from normals. We estimated fABAS from magnetocardiographic recordings (21.4–40.3 weeks of gestation) preclassified in quiet sleep (n = 113, 63 females) and active sleep (n = 286, 145 females) state by cross-validated multivariate linear regression models in a cross-sectional study. According to universal system developmental principles, we included indices that address increasing fluctuation range, increasing complexity, and pattern formation (skewness, power spectral ratio VLF/LF, pNN5). The resulting models constituted fABAS. fABAS explained 66/63% (coefficient of determination R2 of training and validation set) of the variance by age in quiet, while 51/50% in active sleep. By means of a logistic regression model using fluctuation range and fetal age, quiet and active sleep were automatically reclassified (94.3/93.1% correct classifications). We did not find relevant gender differences. We conclude that functional brain age can be assessed based on universal developmental indices obtained from autonomic control patterns. fABAS reflect normal complex functional brain maturation. The presented normative data are supplemented by an explorative study of 19 fetuses compromised by intrauterine growth restriction. We observed a shift in the state distribution towards active awakeness. The lower WGA dependent fABAS values found in active sleep may reflect alterations in the universal developmental indices, namely fluctuation amplitude, complexity, and pattern formation that constitute fABAS.
Development of Brain EEG Connectivity across Early Childhood: Does Sleep Play a Role?  [PDF]
Salome Kurth,Peter Achermann,Thomas Rusterholz,Monique K. LeBourgeois
Brain Sciences , 2013, DOI: 10.3390/brainsci3041445
Abstract: Sleep has beneficial effects on brain function and learning, which are reflected in plastic changes in the cortex. Early childhood is a time of rapid maturation in fundamental skills—e.g., language, cognitive control, working memory—that are predictive of future functioning. Little is currently known about the interactions between sleep and brain maturation during this developmental period. We propose coherent electroencephalogram (EEG) activity during sleep may provide unique insight into maturational processes of functional brain connectivity. Longitudinal sleep EEG assessments were performed in eight healthy subjects at ages 2, 3 and 5 years. Sleep EEG coherence increased across development in a region- and frequency-specific manner. Moreover, although connectivity primarily decreased intra-hemispherically across a night of sleep, an inter-hemispheric overnight increase occurred in the frequency range of slow waves (0.8–2 Hz), theta (4.8–7.8 Hz) and sleep spindles (10–14 Hz), with connectivity changes of up to 20% across a night of sleep. These findings indicate sleep EEG coherence reflects processes of brain maturation— i.e., programmed unfolding of neuronal networks—and moreover, sleep-related alterations of brain connectivity during the sensitive maturational window of early childhood.
Humans Lack iGb3 Due to the Absence of Functional iGb3-Synthase: Implications for NKT Cell Development and Transplantation  [PDF]
Dale Christiansen,Julie Milland,Effie Mouhtouris,Hilary Vaughan,Daniel G. Pellicci,Malcolm J. McConville,Dale I. Godfrey,Mauro S. Sandrin
PLOS Biology , 2012, DOI: 10.1371/journal.pbio.0060172
Abstract: The glycosphingolipid isoglobotrihexosylceramide, or isogloboside 3 (iGb3), is believed to be critical for natural killer T (NKT) cell development and self-recognition in mice and humans. Furthermore, iGb3 may represent an important obstacle in xenotransplantation, in which this lipid represents the only other form of the major xenoepitope Galα(1,3)Gal. The role of iGb3 in NKT cell development is controversial, particularly with one study that suggested that NKT cell development is normal in mice that were rendered deficient for the enzyme iGb3 synthase (iGb3S). We demonstrate that spliced iGb3S mRNA was not detected after extensive analysis of human tissues, and furthermore, the iGb3S gene contains several mutations that render this product nonfunctional. We directly tested the potential functional activity of human iGb3S by expressing chimeric molecules containing the catalytic domain of human iGb3S. These hybrid molecules were unable to synthesize iGb3, due to at least one amino acid substitution. We also demonstrate that purified normal human anti-Gal immunoglobulin G can bind iGb3 lipid and mediate complement lysis of transfected human cells expressing iGb3. Collectively, our data suggest that iGb3S is not expressed in humans, and even if it were expressed, this enzyme would be inactive. Consequently, iGb3 is unlikely to represent a primary natural ligand for NKT cells in humans. Furthermore, the absence of iGb3 in humans implies that it is another source of foreign Galα(1,3)Gal xenoantigen, with obvious significance in the field of xenotransplantation.
Humans Lack iGb3 Due to the Absence of Functional iGb3-Synthase: Implications for NKT Cell Development and Transplantation  [PDF]
Dale Christiansen,Julie Milland,Effie Mouhtouris,Hilary Vaughan,Daniel G Pellicci,Malcolm J McConville,Dale I Godfrey,Mauro S Sandrin
PLOS Biology , 2008, DOI: 10.1371/journal.pbio.0060172
Abstract: The glycosphingolipid isoglobotrihexosylceramide, or isogloboside 3 (iGb3), is believed to be critical for natural killer T (NKT) cell development and self-recognition in mice and humans. Furthermore, iGb3 may represent an important obstacle in xenotransplantation, in which this lipid represents the only other form of the major xenoepitope Galα(1,3)Gal. The role of iGb3 in NKT cell development is controversial, particularly with one study that suggested that NKT cell development is normal in mice that were rendered deficient for the enzyme iGb3 synthase (iGb3S). We demonstrate that spliced iGb3S mRNA was not detected after extensive analysis of human tissues, and furthermore, the iGb3S gene contains several mutations that render this product nonfunctional. We directly tested the potential functional activity of human iGb3S by expressing chimeric molecules containing the catalytic domain of human iGb3S. These hybrid molecules were unable to synthesize iGb3, due to at least one amino acid substitution. We also demonstrate that purified normal human anti-Gal immunoglobulin G can bind iGb3 lipid and mediate complement lysis of transfected human cells expressing iGb3. Collectively, our data suggest that iGb3S is not expressed in humans, and even if it were expressed, this enzyme would be inactive. Consequently, iGb3 is unlikely to represent a primary natural ligand for NKT cells in humans. Furthermore, the absence of iGb3 in humans implies that it is another source of foreign Galα(1,3)Gal xenoantigen, with obvious significance in the field of xenotransplantation.
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