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| High-throughput and single-cell imaging... | Chiropractic and Osteopathy | |
| Background: The nuclear factor-kappaB (NF-kappaB) family of transcription factors plays a role in a wide range of cellular processes including the immune response and cellular growth. In addition, deregulation of the NF-kappaB system has been associated with a number of disease states, including cancer. Therefore, insight into the regulation of NF kappaB activation has crucial medical relevance, holding promise for novel drug target discovery. Transcription of NF-kappaB-induced genes is regulated by differential dynamics of single NF kappaB subunits, but only a few methods are currently being applied to study dynamics. In particular, while oscillations of NF-kappaB activation have been observed in response to the cytokine tumor necrosis factor alpha (TNFalpha), little is known about the occurrence of oscillations in response to bacterial infections. Results: To quantitatively assess NF-kappaB dynamics we generated human and murine monoclonal cell lines that stably express the NF-kappaB subunit p65 fused to GFP. Furthermore, a high-throughput assay based on automated microscopy coupled to image analysis to quantify p65-nuclear translocation was established. Using this assay, we demonstrate a stimulus- and cell line-specific temporal control of p65 translocation, revealing, for the first time, oscillations of p65 translocation in response to bacterial infection. Oscillations were detected at the single-cell level using real-time microscopy as well as at the population level using high-throughput image analysis. In addition, mathematical modeling of NF-kappaB dynamics during bacterial infections predicted masking of oscillations on the population level in asynchronous activations, which was experimentally confirmed. Conclusions: Taken together, this simple and cost effective assay constitutes an integrated approach to infer the dynamics of NF-kappaB kinetics in single cells and cell populations. Using a single system, novel factors modulating NF-kappaB can be identified and analyzed, providing new possibilities for a wide range of applications from therapeutic discovery and understanding of disease to host-pathogen interactions. |
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| A novel link between Sus1 and the cytop... | Chiropractic and Osteopathy | |
| Background: Gene expression is achieved by the coordinated action of multiple factors to ensure a perfect synchrony from chromatin epigenetic regulation through to mRNA export. Sus1 is a conserved mRNA export/transcription factor and is a key player in coupling transcription initiation, elongation and mRNA export. In the nucleus, Sus1 is associated to the transcriptional co-activator SAGA and to the NPC associated complex termed TREX2/THSC. Through these associations, Sus1 mediates the nuclear dynamics of different gene loci and facilitate the export of the new transcripts. Results: In this study, we have investigated whether the yeast Sus1 protein is linked to factors involved in mRNA degradation pathways. We provide evidence for genetic interactions between SUS1 and genes coding for components of P-bodies such as PAT1, LSM1, LSM6 and DHH1. We demonstrate that SUS1 deletion is synthetic lethal with 5'3' decay machinery components LSM1 and PAT1 and has a strong genetic interaction with LSM6 and DHH1. Interestingly, Sus1 overexpression led to an accumulation of Sus1 in cytoplasmic granules, which can co-localise with components of P-bodies and stress granules. In addition, we have identified novel physical interactions between Sus1 and factors associated to P-bodies/stress granules. Finally, absence of LSM1 and PAT1 slightly promotes the Sus1-TREX2 association. Conclusions: In this study, we found genetic and biochemical association between Sus1 and components responsible for cytoplasmic mRNA metabolism. Moreover, Sus1 accumulates in discrete cytoplasmic granules, which partially co-localise with P-bodies and stress granules under specific conditions. These interactions suggest a role for Sus1 in gene expression during cytoplasmic mRNA metabolism in addition to its nuclear function. |
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| Nuclear variants of bone morphogenetic ... | Chiropractic and Osteopathy | |
| Background: Bone morphogenetic proteins (BMPs) contribute to many different aspects of development including mesoderm formation, heart development, neurogenesis, skeletal development, and axis formation. They have previously been recognized only as secreted growth factors, but the present study detected Bmp2, Bmp4, and Gdf5/CDMP1 in the nuclei of cultured cells using immunocytochemistry and immunoblotting of nuclear extracts. Results: In all three proteins, a bipartite nuclear localization signal (NLS) was found to overlap the site at which the proproteins are cleaved to release the mature growth factors from the propeptides. Mutational analyses indicated that the nuclear variants of these three proteins are produced by initiating translation from downstream alternative start codons. The resulting proteins lack N-terminal signal peptides and are therefore translated in the cytoplasm rather than the endoplasmic reticulum, thus avoiding proteolytic processing in the secretory pathway. Instead, the uncleaved proteins (designated nBmp2, nBmp4, and nGdf5) containing the intact NLSs are translocated to the nucleus. Immunostaining of endogenous nBmp2 in cultured cells demonstrated that the amount of nBmp2 as well as its nuclear/cytoplasmic distribution differs between cells that are in M-phase versus other phases of the cell cycle. Conclusions: The observation that nBmp2 localization varies throughout the cell cycle, as well as the conservation of a nuclear localization mechanism among three different BMP family members, suggests that these novel nuclear variants of BMP family proteins play an important functional role in the cell. |
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| Mechanical strain modulates age-related... | Chiropractic and Osteopathy | |
| Background: Previous studies on the effects of aging in human and mouse mesenchymal stem cells suggest that a decline in the number and differentiation potential of stem cells may contribute to aging and aging-related diseases. In this report, we used stromal cells isolated from adipose tissue (ADSCs) of young (8-10 weeks), adult (5 months), and old (21 months) mice to test the hypothesis that mechanical loading modifies aging-related changes in the self-renewal and osteogenic and adipogenic differentiation potential of these cells. Results: We show that aging significantly reduced the proliferation and increased the adipogenesis of ADSCs, while the osteogenic potential is not significantly reduced by aging. Mechanical loading (10% cyclic stretching, 0.5 Hz, 48 h) increased the subsequent proliferation of ADSCs from mice of all ages. Although the number of osteogenic colonies with calcium deposition was increased in ADSCs subjected to pre-strain, it resulted from an increase in colony number rather than from an increase in osteogenic potential after strain. Pre-strain significantly reduced the number of oil droplets and the expression of adipogenic marker genes in adult and old ADSCs. Simultaneously subjecting ADSCs to mechanical loading and adipogenic induction resulted in a stronger inhibition of adipogenesis than that caused by pre-strain. The reduction of adipogenesis by mechanical strain was loading-magnitude dependent: loading with 2% strain only resulted in a partial inhibition, and loading with 0.5% strain could not inhibit adipogenesis in ADSCs. Conclusions: We demonstrate that mechanical stretching counteracts the loss of self-renewal in aging ADSCs by enhancing their proliferation and, at the same time, reduces the heightened adipogenesis of old cells. These findings are important for the further study of stem cell control and treatment for a variety of aging related diseases. |
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| Role of casein kinase 1 in the glucose ... | Chiropractic and Osteopathy | |
| Background: In yeast, glucose-dependent degradation of the Mth1 protein, a corepressor of the glucose transporter gene (HXT) repressor Rgt1, is a crucial event enabling expression of several HXT. This event occurs through a signaling pathway that involves the Rgt2 and Snf3 glucose sensors and yeast casein kinase 1 and 2 (Yck1/2). In this study, we examined whether the glucose sensors directly couple with Yck1/2 to convert glucose binding into an intracellular signal that leads to the degradation of Mth1. Results: High levels of glucose induce degradation of Mth1 through the Rgt2/Snf3 glucose signaling pathway. Fluorescence microscopy analysis indicates that, under glucose-limited conditions, GFP-Mth1 is localized in the nucleus and does not shuttle between the nucleus and cytoplasm. If glucose-induced degradation is prevented due to disruption of the Rgt2/Snf3 pathway, GFP-Mth1 accumulates in the nucleus. When engineered to be localized to the cytoplasm, GFP-Mth1 is degraded regardless of the presence of glucose or the glucose sensors. In addition, removal of Grr1 from the nucleus prevents degradation of GFP-Mth1. These results suggest that glucose-induced, glucose sensor-dependent Mth1 degradation occurs in the nucleus. We also show that, like Yck2, Yck1 is localized to the plasma membrane via C-terminal palmitoylation mediated by the palmitoyl transferase Akr1. However, glucose-dependent degradation of Mth1 is not impaired in the absence of Akr1, suggesting that a direct interaction between the glucose sensors and Yck1/2 is not required for Mth1 degradation. Conclusion: Glucose-induced, glucose sensor-regulated degradation of Mth1 occurs in the nucleus and does not require direct interaction of the glucose sensors with Yck1/2. |
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| Message d?intérêt public : Certaines cl... | Chiroblog | |
| J’ai récemment été étonné de constater que plusieurs cliniques, au Québec, offraient des soins de décompression neuro-vertébrale alors qu?en réalité, il s?agit de traitements de flexion-distraction. La technique « Cox » de flexion-distraction est très répandue en chiropratique et est réalisée grâce à un équipement très différent de celui utilisé en décompression neuro-vertébrale. Mais avant d?entrer dans le [...] |
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| La vérité concernant la décompression n... | Chiroblog | |
| D?abord, il faut que vous sachiez que je suis convaincu que la décompression neurovertébrale peut aider un très grand pourcentage de patients qui souffrent d?une hernie discale, d?un bombement du disque, d?une discopathie causé par la dégénérescence dû à l?arthrose (usure prématurée du disque ou amincissement du disque) et [...] | ||
| Les 7 étapes du blanchiment des dents p... | Chiroblog | |
| SOS Dents Blanches offre un service de blanchiment des dents est à la fine pointe de la technologie, utilisant le même appareil et les même gels blanchissant que les spécialistes utilisent dans leur clinique dentaire. Le blanchiment des dents en 7 étapes Voici comment se déroule le blanchiment des dents de base d’une durée de 15 minutes: Cliquez ici [...] |
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| La Cour de l?Alberta rejette un recours... | Chiroblog | |
| 13 janvier 2010, Edmonton, Alberta. – Dans les motifs de jugement rendu le 11 Janvier 2010, Monsieur le juge Paul Belzil de la Cour l’Alberta a refusé la certification du recours collectif lancé contre le Collège et l’Association des chiropraticiens de l’Alberta (ACAC). L?ACAC a été victorieux sur toutes les questions. L?Honorable Juge Belzil a trouvé [...] |
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| Nouvelle clinique de décompression neur... | Chiroblog | |
| Une nouvelle clinique de décompression neuro vertébrale ouvrira ses portes à Laval en février 2010. Après celle de Saint-Jean-sur-Richelieu et de Granby, la clinique de Laval permettra à la Clinique Tag d’offrir ses services aux citoyens de Laval ainsi que ceux de la Rive-Nord et des Laurentides. Rive-Nord de Montréal – Laval Dr Sylvain Desforges, chiropraticien Centre [...] |
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| La différence entre la chiropratique et... | Chiroblog | |
| Blanchiment des dents à domicile | Chiroblog | |
| Prescription médicale | SOS Hernie Discale | |
| Assurances | SOS Hernie Discale | |
| Décompression neurovertébrale | SOS Hernie Discale | |
| Les infrarouges longs: adieu cellulite ... | Chiroblog | |
| Les Infrarouges Longs (far infrared) et... | Chiroblog | |
| SOS Tunnel Carpien ? La solution sans c... | Chiroblog | |
| Honoraires | SOS Hernie Discale | |
| Comment devenir un patient ? | SOS Hernie Discale | |
| Statistiques concernant les maux de dos | SOS Hernie Discale | |
| Statistiques sur la décompression verté... | SOS Hernie Discale | |
| Diagnostic de la hernie discale | SOS Hernie Discale | |
| Des professionnels dévoués | SOS Hernie Discale | |
| La décompression vertébrale démystifiée | SOS Hernie Discale | |
| American Chiropractic Association Names... | American Chiropractic Association | |
| Anthem Misrepresents ACA Position in Ad... | American Chiropractic Association | |
| Doctors of Chiropractic, Students and S... | American Chiropractic Association | |
| Congressional Chiropractic Supporters P... | American Chiropractic Association | |
| Study Expert Validates Chiropractic Sta... | American Chiropractic Association | |
