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A novel Lozenge gene in silkworm, Bombyx mori regulates the melanization response of hemolymphXu, M., Wang, X., Tan, J., Zhang, K., Guan, X., Patterson, Laurence H., Ding, H., Cui, H. 07 September 2015 (has links)
No / Runt-related (RUNX) transcription factors are evolutionarily conserved either in vertebrate or invertebrate. Lozenge (Lz), a members of RUNX family as well as homologue of AML-1, functions as an important transcription factor regulating the hemocytes differentiation. In this paper, we identified and characterized RUNX family especially Lz in silkworm, which is a lepidopteran model insect. The gene expression analysis illustrated that BmLz was highly expressed in hemocytes throughout the whole development period, and reached a peak in glutonous stage. Over-expression of BmLz in silkworm accelerated the melanization process of hemolymph, and led to instantaneously up-regulation of prophenoloxidases (PPOs), which were key enzymes in the melanization process. Further down-regulation of BmLz expression by RNA interference resulted in the significant delay of melanization reaction of hemolymph. These findings suggested that BmLz regulated the melanization process of hemolymph by inducing PPOs expression, and played a critical role in innate immunity defense in silkworm.
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Samverkan med vårdnadshavare : I dag- och i dygnet-runt-öppna förskoleverksamheter / Collaboration with parents : At day-open and 24-hour child care centerHaddad, Nasim, Lind, Sara January 2013 (has links)
BakgrundSamverkan med vårdnadshavare är en viktig del av förskolans uppdrag. Förskollärarna ska enligt läroplanen för förskolan (Lpfö 98 rev. 2010, s. 13) utveckla förtroendefulla relationer till vårdnadshavarna och verksamheterna komplettera hemmen. Hemmets och familjernas behov är föränderliga. I studiens bakgrund återfinns en historisk tillbakablick på svenska förskolans framväxt. I bakgrunden lyfts även samverkans betydelse, pedagogernas roll, vårdnadshavares önskemål, dygnet-runt-öppna förskoleverksamheter samt vägar till samverkan och vägarnas innehåll.SyfteStudiens syfte är att ge en bild av förskollärares berättelser kring hur samverkan med vårdnadshavare sker i dygnet-runt-öppna samt i dagöppna förskoleverksamheter.MetodUndersökningen är en kvalitativ studie, som genomförts med halvstrukturerad parintervju som redskap. I undersökningen deltog sex stycken förskollärare från respektive verksamhetsform.ResultatI studien framkom både likheter och skillnader inom samverkan med vårdnadshavare i dagöppna och dygnet-runt-öppna förskoleverksamheter. Viktigaste samverkansformen anses vara den dagliga kontakten och familjernas känsla av trygghet ses som ytterst viktig. Dock finns olika förutsättningar för hur samverkan utformas och till viss del hur mycket tid som kan avsättas. I dygnet-runt-öppna verksamheter ses ibland exempelvis den tidsmässiga fördelen av att kunna förbereda under nätter då barnen sover. / Program: Lärarutbildningen
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Nattens betydelse för barns anknytning : en kvalitativ studie om barns anknytningsmönster på dygnet-runt-förskola. / The importance of the night for children's attachment : a qualitative study about children’s attachment patterns on day and night preschools.Hansson, Lovisa January 2018 (has links)
Inledning Sedan 2005 har antalet kommuner som erbjuder dygnet-runt-förskola fördubblats och antalet barn som behöver omsorg på obekväma tider på dygnet ökar (Skolverket 2017). Många barn som är inskrivna på dygnet-runt-förskolor tillbringar långa dagar och ibland flera dygn utan att komma hem emellan och frågan är om de påverkas av så långa vistelsetider på förskolan. Den teori som har legat till grund i studien är John Bowlbys anknytningsteori som säger att små barn är i behov av sina primära anknytningspersoner och ej bör separeras från dessa under längre tidsperioder. Studien undersöker vilka faktorer som påverkar 0–3 åriga barns anknytning på dygnet-runt-förskolor. Syfte Syftet med denna studie är att undersöka ett antal förskollärares erfarenheter och upplevelser av barn som sover på en dygnet-runt-förskola. Fokus kommer att ligga på de barn som sover nätter på förskolan och på vilket sätt förskollärarna anser att deras anknytning påverkas. Metod En kvalitativ metod har använts där fyra semistrukturerade intervjuer har genomförts. Förskollärare på två olika dygnet-runt-förskolor har deltagit där alla har minst tre års erfarenhet från att arbeta på dygnet-runt-förskola. Resultat Resultatet visar att de förskollärare som intervjuats anser att de barn som sover flera dygn på förskolan utan att komma hem till sina primära anknytningspersoner mår sämre och visar tecken på ett undvikande anknytningsmönster. Barn som sover sällan på förskolan upplevs antingen sova sämre och vara ledsnare eller klara det bra vilket tyder på att det inte finns någon färdig mall som fungerar för alla barn. Barn som regelbundet sover två till tre nätter i veckan anser förskollärarna mår bra, har lättare att anpassa sig till situationen och tenderar att ha ett tryggt anknytningsmönster. Vidare är det bättre att lämna barn över två år på dygnet-runt-förskola då barn under två år anses vara för små och kan inte verbalt påverka sin situation. Undersökningen visar också att de stora personalgrupperna som arbetar med barnen upplevs påverka några av de yngsta barnen negativt men att det går bra för de flesta barnen. Även barnens hemsituation påverkar barnens trygghet på förskolan och barn med trygga hemsituationer tenderar att ha det lättare och vara trygga individer även på förskolan. Barn med otrygga hemsituationer upplever förskollärarna sover sämre och är otrygga barn även på förskolan.
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Forshaga kommuns potential att bli en året runt-destination : Sett till nuvarande utbud och marknadsföringHalvardsson, Tanja, Stedt, Hampus January 2020 (has links)
No description available.
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Genetic and Functional Characterization of RUNX2Stephens, Alexandre, N/A January 2007 (has links)
RUNX2 belongs to the RUNT domain family of transcription factors of which three have been identified in humans (RUNX1, RUNX2 and RUNX3). RUNX proteins are vital for metazoan development and participate in the regulation of cellular differentiation and cell cycle progression (Coffman, 2003). RUNX2 is required for proper bone formation by driving the differentiation of osteoblasts from mesenchymal progenitors during development (Ducy et al, 1997; Komori et al, 1997; Otto et al, 1997). RUNX2 is also vital for chondrocyte maturation by promoting the differentiation of chondrocytes to the hypertrophic phenotype (Enomoto et al, 2000). The consequences of completely disrupting the RUNX2 locus in mice provided compelling and conclusive evidence for the biological importance of RUNX2 where knockout mice died shortly after birth with a complete lack of bone formation (Komori et al, 1997; Otto et al, 1997). A further indication of the requisite role of RUNX2 in skeletal development was the discovery that RUNX2 haploinsufficiency in humans and mice caused the skeletal syndrome Cleidocranial Dysplasia (CCD) (Mundlos et al, 1997; Lee et al, 1997). A unique feature of RUNX2 is the consecutive polyglutamine and polyalanine tracts (Q/A domain). Mutations causing CCD have been observed in the Q/A domain of RUNX2 (Mundlos et al, 1997). The Q/A domain is an essential part of RUNX2 and participates in transactivation function (Thirunavukkarasu et al, 1998). Previous genotyping studies conducted in our laboratory identified several rare RUNX2 Q/A variants in addition to a frequently occurring 18 base pair deletion of the polyalanine tract termed the 11Ala allele. Analysis of serum parameters in 78 Osteoarthritis patients revealed the 11Ala allele was associated with significantly decreased osteocalcin. Furthermore, analysis of 11Ala allele frequencies within a Geelong Osteoporosis Study (GOS) fracture cohort and an appropriate age matched control group revealed the 11Ala allele was significantly overrepresented in fracture cases indicating an association with increased fracture risk. To further investigate the 11Ala allele and rare Q/A variants, 747 DNA samples from the Southeast Queensland bone study were genotyped using PCR and PAGE. The experiment served two purposes: 1) to detect additional rare Q/A variants to enrich the population of already identified mutants and 2) have an independent assessment of the effect of the 11Ala allele on fracture to either support or refute our previous observation which indicated the 11Ala allele was associated with an increased risk of fracture in the GOS. From the 747 samples genotyped, 665 were WT, 76 were heterozygous for the 11Ala allele, 5 were homozygous for the 11Ala allele and 1 was heterozygous for a rare 21 bp deletion of the polyglutamine tract. Chi-square analysis of RUNX2 genotype distributions within fracture and non-fracture groups in the Southeast Queensland bone study revealed that individuals that carried at least one copy of the 11Ala allele were enriched in the fracture group (p = 0.16, OR = 1.712). The OR of 1.712 was of similar magnitude to the OR observed in the GOS case-control investigation (OR = 1.9) providing support for the original study. Monte-Carlo simulations were used to combine the results from the GOS and the Southeast Queensland bone study. The simulations were conducted with 10000 iterations and demonstrated that the maximum probability of obtaining both study results by chance was less than 5 times in two hundred (p < 0.025) suggesting that the 11Ala allele of RUNX2 was associated with an increased fracture risk. The second element of the research involved the analysis of rare RUNX2 Q/A variants identified from multiple epidemiological studies of bone. Q/A repeat variants were derived from four populations: the GOS, an Aberdeen cohort, CAIFOS and a Sydney twin study. Collectively, a total of 20 rare glutamine and one alanine variants were identified from 4361 subjects. All RUNX2 Q/A variants were heterozygous for a mutant allele and a wild type allele. Analysis of incident fracture during a five year follow up period in the CAIFOS revealed that Q-variants (n = 8) were significantly more likely to have fractured compared to non-carriers (p = 0.026, OR 4.932 95% CI 1.2 to 20.1). Bone density data as measured by quantitative ultrasound was available for CAIFOS. Analysis of BUA and SOS Z-scores revealed that Q-repeat variants had significantly lower BUA (p = 0.031, mean Z-score of -0.79) and a trend for lower SOS (p = 0.190, mean Z-score of -0.69). BMD data was available for all four populations. To normalize the data across the four studies, FN BMD data was converted into Z-scores and the effect of the Q/A variants on BMD was analysed using a one sample approach. The analysis revealed Q/A variants had significantly lower FN BMD (p = 0.0003) presenting with a 0.65 SD decrease. Quantitative transactivation analysis was conducted on RUNX2 proteins harbouring rare glutamine mutations and the 11Ala allele. RUNX2 proteins containing a glutamine deletion (16Q), a glutamine insertion (30Q) and the 11Ala allele were overexpressed in NIH3T3 and HEK293 cells and their ability to transactivate a known target promoter was assessed. The 16Q and 30Q had significantly decreased reporter activity compared to WT in NIH3T3 cells (p = 0.002 and 0.016, for 16Q and 30Q, respectively). In contrast 11Ala RUNX2 did not show significantly different promoter activation potential (p = 0.54). Similar results were obtained in HEK293 cells where both the 16Q and 30Q RUNX2 displayed decreased reporter activity (p=0.007 and 0.066 for 16Q and 30Q respectively) whereas the 11Ala allele had no material effect on RUNX2 function (p = 0.20). The RUNX2 gene target reporter assay provided evidence to suggest that variation within the glutamine tract of RUNX2 was capable of altering the ability of RUNX2 to activate a known target promoter. In contrast, the 11Ala allele showed no variation in RUNX2 activity. The third feature of the research served the purpose of identifying potential RUNX2 gene targets with particular emphasis on discovering genes cooperatively regulated by RUNX2 and the powerful bone promoting agent BMP2. The experiment was conducted by creating stably transfected NIH3T3 cells lines overexpressing RUNX2 or BMP2 or both RUNX2 and BMP2. Microarray analysis revealed very few genes were differentially regulated between standard NIH3T3 cells and cells overexpressing RUNX2. The results were confirmed via RT-PCR analysis which demonstrated that the known RUNX2 gene targets Osteocalcin and Matrix Metalloproteinase-13 were modestly induced 2.5 fold (p = 0.00017) and 2.1 fold (p = 0.002) respectively in addition to identifying only two genes (IGF-II and SCYA11) that were differentially regulated greater than 10 fold. IGF-II and SYCA11 were significantly down-regulated 27.6 fold (p = 1.95 x 10-6) and 10.1 fold (p = 0.0002) respectively. The results provided support for the notion that RUNX2 on its own was not sufficient for optimal gene expression and required the presence of additional factors. To discover genes cooperatively regulated by RUNX2 and BMP2, microarray gene expression analysis was performed on standard NIH3T3 cells and NIH3T3 cells stably transfected with both RUNX2 and BMP2. Comparison of the gene expression profiles revealed the presence of a large number of differentially regulated genes. Four genes EHOX, CCL9, CSF2 and OSF-1 were chosen to be further characterized via RT-PCR. Sequential RT-PCR analysis on cDNA derived from control cells and cells stably transfected with either RUNX2, BMP2 or both RUNX2/BMP2 revealed that EHOX and CSF2 were cooperatively induced by RUNX2 and BMP2 whereas CCL9 and OSF-1 were suppressed by BMP2. The overexpression of both RUNX2 and BMP2 in NIH3T3 fibroblasts provided a powerful model upon which to discover potential RUNX2 gene targets and also identify genes synergistically regulated by BMP2 and RUNX2. The fourth element of the research investigated the role of RUNX2 in the ascorbic acid mediated induction of MMP-13 mRNA. The study was carried out using NIH3T3 cell lines stably transfected with BMP2, RUNX2 and both BMP2 and RUNX2. The cell lines were grown to confluence and subsequently cultured for a further 12 days in standard media or in media supplemented with AA. RT-PCR analysis was used to assess MMP-13 mRNA expression. The RT-PCR results demonstrated that AA was not sufficient for inducing MMP-13 mRNA in NIH3T3 cells. In contrast RUNX2 significantly induced MMP-13 levels 85 fold in the absence of AA (p = 0.0055) and upregulated MMP-13 mRNA levels 254 fold in the presence of AA (p = 0.0017). The results demonstrated that RUNX2 was essential for the AA mediated induction of MMP-13 mRNA in NIH3T3 cells. The effect of BMP2 on MMP-13 expression was also investigated. BMP2 induced MMP-13 mRNA transcripts a modest 3.8 fold in the presence of AA (p = 0.0027). When both RUNX2 and BMP2 were overexpressed in the presence of AA, MMP-13 mRNA levels were induced a massive 4026 fold (p = 8.7 x 10-4) compared to control cells. The investigation revealed that RUNX2 was an essential factor for the AA mediated induction of MMP-13 and that RUNX2 and BMP2 functionally cooperated to regulate MMP-13 mRNA levels.
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Identifying Genes Influencing Bone Mineral DensityVaughan, Tanya, n/a January 2004 (has links)
Bone mineral density (BMD) is a reflection of the action of osteoblasts compared to osteoclasts. An imbalance in the activity of osteoblasts or osteoclasts, results in bone disease such as osteoporosis caused by overactive osteoclasts. BMD is influenced by genetic and environmental factors as demonstrated through twin studies, association studies and linkage analysis (Ralston, 1999). Several polymorphisms involved in the determination of BMD have been identified, with Vitamin D receptor and Collagen Type 1 showing reproducible associations. To identify genes influencing BMD two distinct strategies have been employed: 1) To determine if DNA polymorphism within the runt related transcription factor (RUNX2) gene is a determinant of BMD and fracture in women. 2) The identification of RANKL target genes in osteoclastogenesis. RUNX2 is a runt domain transcription factor (Werner et al., 1999) essential for osteoblast differentiation (Lee et al., 1997). RUNX2 gene knock-out mice have no osteoblasts due to a failure in osteoblast differentiation and consequently unmineralised skeletons, (Komori et al., 1997; Otto et al., 1997). In humans, mutations in RUNX2 cause cleidocranial dysplasia (CCD), a disorder characterised by hypoplasia or aplasia of the clavicles, short stature, supernumerary teeth, patent fontanelles and other changes in skeletal patterning and growth (Mundlos et al., 1997). RUNX2 contains a poly-glutamine poly-alanine (polyQ/polyA) repeat where mutations causing cleidocranial dysplasia have been observed. BMD has not been routinely examined in CCD, two studies have identified CCD patients with lower BMD with one fracture case identified (Quack et al., 1999; Bergwitz et al., 2001). The central role of RUNX2 in determining osteoblast differentiation makes RUNX2 a prime candidate gene for regulating adult bone density. To determine if polymorphism was present in the polyQ/polyA tract the repeat was amplified within the upper and lower deciles of femoral neck (FN) BMD in the Geelong Osteoporosis study (GOS). The upper and lower deciles of FN BMD acted as a surrogate for genotyping the entire cohort. This study identified two common variants within the polyA repeat: an 18 base pair deletion (11Ala) and a synonymous alanine codon polymorphism with alleles, GCA and GCG (noted as A and G alleles, respectively). The 11Ala and SNP polymorphism are found on codon 64 and 66 respectively (RUNX2 MRIPV variant). A allele frequencies were significantly different in a comparison of the upper and lower deciles of FN BMD (p=0.019). In 495 randomly selected women of the Geelong Osteoporosis Study (GOS), the A allele was associated with higher BMD at all sites tested. The association was maximal at the ultra-distal radius (p=0.001). In a separate fracture study, the A allele was significantly protective against Colles' fracture in elderly women but not spine and hip fracture. The 11Ala polymorphism was not related to BMD in GOS. To further decipher the role of the RUNX2 A allele we genotyped 992 women from a Scottish cohort. The alleles of RUNX2 within the glutamine/alanine repeat were determined by MspA1I restriction digest. To examine the possible influence on estrogen related therapies or estrogen status on the potential genetic effect conferred by RUNX2, we divided the cohort by menopausal and hormone replacement therapy status. Within postmenopausal Scottish women the RUNX2 A allele was associated with significantly higher FN BMD (p=0.028, n=312) but not lumbar spine (LS) BMD. The A allele was associated with higher FN BMD (p=0.035) within a postmenopausal subgroup of the population (n=312). To investigate the effect of weight on the RUNX2 alleles the Scottish cohort was segregated into thin/normal (BMI ≥ 25 kg/m2) and overweight /obese (BMI > 25 kg/m2). RUNX2 A allele showed a stronger effect on FN BMD in postmenopausal women above the median BMI. The 11Ala RUNX2 deletion allele was significantly associated with decreased LS BMD (p=0.018) within overweight/obese women (n=546). The 11Ala allele was significantly associated with increased levels of pyridinoline (p=0.014) and deoxypyridinoline (p=0.038) in the HRT treated subgroup of the population (n=492). Glutamine variants and an alanine insertion were identified within the group. These data suggest that the RUNX2 11Ala and A alleles exert differing affects on BMD showing preference for different skeletal sites in a weight dependent manner. We genotyped 78 individuals from an osteoarthritic population to elucidate the role of the RUNX2 alleles on markers of bone turnover and inflammation. The RUNX2 11Ala allele was significantly associated with decreased osteocalcin (OC) serum levels (p = 0.01). The RUNX2 A allele was significantly related to reduced tumor necrosis factor alpha (TNF-alpha) serum levels (p = 0.004). RUNX2 is known to bind to the OC promoter. An OC promoter polymorphism is found 7bp upstream from a putative RUNX2 binding site. We hypothesized that OC polymorphism may effect the RUNX2 transactivation of the OC gene and thus affect OC serum levels. OC promoter polymorphism was not related to OC serum levels (n=78). These data present a novel link between RUNX2 alleles and OC and TNF serum levels, providing putative mechanisms of action for the RUNX2 alleles. Further studies in larger populations are required to confirm these findings. Ten individuals within the GOS and the Scottish cohort were found to carry rare mutations of the polyQ/polyA repeat. All polyQ variants had a normal polyA repeat (17 amino acids) and were heterozygous for a normal 23Q/17A allele. Variants observed were 15, 16, 24 and 30Q. One individual was observed with an extended polyA repeat (24A). Patient records indicated otherwise unremarkable clinical history except for fracture in 4/10 individuals from GOS (hip and spine). BMD data from the LS and the FN were expressed as T-scores, a measure that relates BMD in terms of standard deviations below the young normal value. In addition, BMD data were also expressed as Z-scores around the age-mean. Under the null hypothesis, where RUNX2 Q repeat variation has no effect on BMD, Z scores would be expected to be distributed around a mean of zero. However, when all variants were pooled the BMD was significantly lower than expected. This effect persisted when deletion variants were considered alone. The effect was stronger on FN BMD (p=0.001) rather than LS BMD (p=0.096), reflecting either difference in precision of BMD measurements at these sites or perhaps a differential genetic effect on different skeletal sites. These data suggest that polyQ and polyA variants are associated with significantly lower BMD, and may be an important determinant for fracture. Glutamine variants exist at high frequency (~0.7%): this rate of mutation could be important when considering large populations at risk of age related osteoporosis. Considering that these subjects are heterozygous for a normal allele, it suggests that a more severe phenotype might be expected in rare subjects homozygous for glutamine repeat variants. In summary, this study investigated the role of novel polymorphisms and rare variants of the RUNX2 gene in influencing BMD, fracture and markers of bone turnover. Two common polymorphisms were identified within the polyA repeat: an 18 base pair deletion and a synonymous alanine codon polymorphism with alleles, A and G. The A allele was associated with increased BMD and was protective against a common form of osteoporotic fracture within a Geelong population. To verify these findings the RUNX2 alleles were genotyped in 992 women from a Scottish cohort. The magnitude and the direction of the effect of the A allele was maintained in the Scottish cohort. Interestingly, the A allele was shown to exert a menopause specific effect, with postmenopausal women showing the strongest effect. On re-analysis of the GOS data the post-menopausal women were found to drive the significance identified in the cohort. The magnitude of the effect of the A allele on BMD was greater in overweight/obese postmenopausal women indicating a gene-weight interaction for RUNX2. The RUNX2 11Ala allele showed a significant relationship with decreased LS BMD in overweight/obese Scottish women. The 11Ala allele was also associated with higher levels of urinary PYD and DPD in women treated with HRT, indicating higher levels of bone turnover in carriers of the 11Ala allele. In contrast to the Scottish cohort, no significant association with heterozygous carriers of 11Ala was observed in GOS, although a significant association was detected for homozygous carriers and LS BMAD. The 11 Ala RUNX2 allele was significantly associated with decreased serum osteocalcin levels and the A allele was significantly associated with TNF in OA patients. Glutamine variants and an alanine insertion were identified within Geelong and Scottish cohorts, which showed low Z and T scores suggesting that RUNX2 variants may be related to genetic effects on BMD and osteoporosis. Polymorphism of the polyQ/polyA region of RUNX2 were identified within this study were shown to associate with significant differences in BMD. The A allele showed a significant association with increased BMD in postmenopausal women from a Geelong and Scottish cohort, with a decreased frequency of the A allele observed in Colles' fracture patients from Geelong. The 11Ala deletion allele was significantly associated with decreased LS BMD and increases in markers of bone turnover in the Scottish cohort. A significant decrease in OC serum levels was observed in OA patients suggesting a direct effect of the allele on the transactivation of the RUNX2 gene. Rare variants of RUNX2 were identified which showed low BMD. These studies have provided insight into the role of RUNX2 in influencing BMD, further studies are required to verify the role of the A allele on BMD and fracture, the role of the rare variants and to identify the precise mechanisms behind the observed changes in BMD. - 2) The identification of RANKL target genes in osteoclastogenesis. Osteoclastogenesis is regulated in vivo by the action of osteoblast/stromal cells that express membrane bound, receptor activator of NF-kB ligand (RANKL). Monocytes treated in vitro with a soluble form of RANKL and macrophage colony stimulating factor (M-CSF) differentiate to osteoclasts, whereas monocytes treated with M-CSF alone differentiate to macrophage-like cells. The gene expression profile of human osteoclasts has not been extensively explored. Genes highly expressed by rabbit osteoclasts were identified through random sequencing of an osteoclast cDNA library (Sakai et al., 1995). Differential gene expression of mouse osteoclastogenesis was elucidated by array analysis (Cappellen et al., 2002). To identify genes important for human osteoclastogenesis, total RNA was isolated from monocytes treated for three weeks with either M-CSF alone or with RANKL and M-CSF. RANKL treatment for 3 weeks and 12 hours was investigated in this study, to complement previous data. Differential display was performed on RNA (12 hour treatment with RANKL) and differential gene expression profiles examined. The differential display products were pooled to generate a probe for screening a gene array system derived from a human osteoclast cDNA library. cDNA (3 week treatment with RANKL) hybridisation experiments against the array revealed additional regulated genes. Gene clones that showed significant regulation in M-CSF and RANKL treated cells compared M-CSF treated cells represent genes that are targets for RANKL-specific regulation. Osteopontin, creatine kinase and various mitochondrial genes were up regulated by the treatment of RANKL. Changes in gene expression observed in the array data were confirmed with real-time PCR using mRNA derived from in vitro induced osteoclasts. Cathepsin K gene expression was more than 300 fold greater in osteoclasts compared to macrophage-like cells after one week treatment with RANKL and M-CSF. Cystatin C expression showed a six-fold induction at two weeks of RANKL and M-CSF treatment and cystatin B showed a steady increase in expression. Some of these regulated genes may provide useful targets for influencing BMD.
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Vascular calcification in rat cultured smooth muscle cells : a role for nitric oxideAlsabeelah, Nimer Fehaid N. January 2016 (has links)
The underlying inflammatory storm in renal or diabetic disease may induce expression of inducible nitric oxide synthase (iNOS). Similarly, expression of iNOS or nitric oxide (NO) production in vascular smooth muscle cells (VSMCs) in a calcifying environment, may promote vascular calcification (VC) (Zaragoza et al., 2006). However, emerging data suggests that NO generated by either endothelial nitric oxide synthase (eNOS) or iNOS may protect VSMCs from VC (Kanno et al., 2008). Thus, the role of NO and its associated enzymes in the development of VC is unclear. The aim of this study was to identify whether NO produced by iNOS regulates calcification in VSMCs, and to further understanding of potential mechanisms that may mediate the actions of NO/iNOS. A significant and sustained production of NO by iNOS, which peaked at day 3 and declined thereafter was found in rat aortic smooth muscle cells (RASMCs) that were preactivated with lipopolysaccharide (LPS; 100μg ml-1) and interferon gamma (IFN-γ;100U ml-1) in the presence of calcification buffer (CB) containing calcium chloride (CaCl2; 7mM) and β-glycerophosphate (β-GP; 7mM). This was associated with formation of hydroxyapatite crystals (HA) or calcification plaques, observed via alizarin red staining (ARS) and/or fourier transform infrared (FT-IR) analysis. However, when RASMCs were incubated with the iNOS inhibitor GW274150 at 10 μM, together with LPS + IFN-γ + CB, HA crystal formation was abolished. When RASMCs were pretreated with diethylenetriamine/nitric oxide adduct (NOC 18) at either 30 or 50 μM for an hour prior to addition of CB, to generate NO; calcium levels were elevated leading to form HA crystals. However, the elevation of calcium caused by the presence of NO generated via iNOS, did not result in phosphorylation of mitogen activated protein kinases (p38 MAPK), extracellular signal-regulated kinases (Erks), and protein kinase B. Furthermore, there was a reduction of Runx2 levels (pro-calcific factor) which could be another pro-calcific factor involved in this mechanism. These findings suggest that NO may indeed play a fundamental role in calcification, enhancing mineralisation of smooth muscle cells. Furthermore, the expression of iNOS/ NO appears to be enhanced under conditions that favour calcification and these together may contribute to enhanced calcification with potential detrimental consequences in vivo.
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The hematopoietic transcription factor RUNX1 : a structural viewBäckström, Stefan January 2004 (has links)
<p>The malfunction of the transcriptional regulator RUNX1 is the major cause of several variants of acute human leukemias and its normal function is to regulate the development of the blood system in concert with other transcriptional co-regulators. RUNX1 belongs to a conserved family of heterodimeric transcription factors that share a conserved DNA binding domain, the Runt domain (RD), named after the first member of this group – Runt - found in Drosophila melanogaster. The binding partner CBFβ serves as a regulator of RUNX by enhancing its DNA binding affinity through an allosteric mechanism.</p><p>The main focus ofo my thesis work has been the crystallization and structural analysis of the RUNX1 RD and involved also more technical methodological aspects that can be applied to X-ray crystallography in general.</p><p>The high resolution crystal structure of the free RD shows that this immunoglobulin-like molecule undergoes significant structural changes upon binding to both CBFβ and DNA. This involves a large flip of the L11 loop from a closed conformation in the free protein to an open conformation when CBFβ and/or DNA are bound. We refer to this transition as the “S-switch”. Smaller but significant conformational changes in other parts of the RD accompany the “S-switch”. We suggest that CBFβ triggers and stabilizes the “S-switch” which leads to the conversion of the RD into a conformation enhanced for DNA binding.</p><p>During the structural analysis of the RD we identified two chloride ions that are coordinated by residues otherwise involved in DNA binding. In electrophoretic mobility-shift analyses (EMSA) we demonstrated a chloride ion concentration dependent stimulation of the DNA binding affinity of RUNX1. We further showed by NMR line width broadening experiments that the chloride binding occurred within the physiological range. A comparable DNA binding stimulation of RUNX1 was seen in the presence of negative amino acids. This suggests a regulation of the DNA binding activity of RUNX1 proteins through acidic amino acid residues possibly provided by activation domains of transcriptional co-regulators that interact with RUNX1.</p><p>The use of the anomalous signal from halide ions has become a powerful technique for obtaining phase information. By replacing the sodium chloride with potassium bromide in the crystallisation conditions of the RD, we could demonstrate in a single wavelength anomalous diffraction (SAD) experiment that the anomalous signal from 2 bromide ions were sufficient to phase a 16 kDa protein. Due to lack of completeness in the low-resolution shells caused by overloaded intensities, density modification schemes failed and the resulting electron density maps were not interpretable. By combining the highresolution</p><p>synchrotron data with low-resolution data from a native data set collected on a home X-ray source, the density modified bromide phases gave easily traceable maps.</p>
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The hematopoietic transcription factor RUNX1 : a structural viewBäckström, Stefan January 2004 (has links)
The malfunction of the transcriptional regulator RUNX1 is the major cause of several variants of acute human leukemias and its normal function is to regulate the development of the blood system in concert with other transcriptional co-regulators. RUNX1 belongs to a conserved family of heterodimeric transcription factors that share a conserved DNA binding domain, the Runt domain (RD), named after the first member of this group – Runt - found in Drosophila melanogaster. The binding partner CBFβ serves as a regulator of RUNX by enhancing its DNA binding affinity through an allosteric mechanism. The main focus ofo my thesis work has been the crystallization and structural analysis of the RUNX1 RD and involved also more technical methodological aspects that can be applied to X-ray crystallography in general. The high resolution crystal structure of the free RD shows that this immunoglobulin-like molecule undergoes significant structural changes upon binding to both CBFβ and DNA. This involves a large flip of the L11 loop from a closed conformation in the free protein to an open conformation when CBFβ and/or DNA are bound. We refer to this transition as the “S-switch”. Smaller but significant conformational changes in other parts of the RD accompany the “S-switch”. We suggest that CBFβ triggers and stabilizes the “S-switch” which leads to the conversion of the RD into a conformation enhanced for DNA binding. During the structural analysis of the RD we identified two chloride ions that are coordinated by residues otherwise involved in DNA binding. In electrophoretic mobility-shift analyses (EMSA) we demonstrated a chloride ion concentration dependent stimulation of the DNA binding affinity of RUNX1. We further showed by NMR line width broadening experiments that the chloride binding occurred within the physiological range. A comparable DNA binding stimulation of RUNX1 was seen in the presence of negative amino acids. This suggests a regulation of the DNA binding activity of RUNX1 proteins through acidic amino acid residues possibly provided by activation domains of transcriptional co-regulators that interact with RUNX1. The use of the anomalous signal from halide ions has become a powerful technique for obtaining phase information. By replacing the sodium chloride with potassium bromide in the crystallisation conditions of the RD, we could demonstrate in a single wavelength anomalous diffraction (SAD) experiment that the anomalous signal from 2 bromide ions were sufficient to phase a 16 kDa protein. Due to lack of completeness in the low-resolution shells caused by overloaded intensities, density modification schemes failed and the resulting electron density maps were not interpretable. By combining the highresolution synchrotron data with low-resolution data from a native data set collected on a home X-ray source, the density modified bromide phases gave easily traceable maps.
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Exploration of the next generation of green electricity procurement strategies : Evaluation of 24/7 carbon-free electricity and emissionality and their implications for carbon accounting / Utforskning av upphandlingar för nästa generations gröna el : Utvärdering av 24/7 koldioxidfri el och dess utsläpp samt deras konsekvenser för koldioxidredovisningFàbrega Ferrer, Eloi January 2022 (has links)
Under the current climate emergency, the electricity industry is taking quick steps to introduce new technology and market processes that could contribute to the decarbonization of the power system. The creation of the energy attribute certificates more than two decades ago has allowed consumers to choose the origin of their electricity. This market instrument has provided a new tool for tracking carbon-free electricity. It is how corporates can reduce their market-based emissions under the Scope 2 Green House Gas Protocol, a practice called annual matching of certificates. However, there are new trends in green electricity procurement that intend to improve the current system. These are called 24/7 carbon-free electricity and emissionality. To bring added value, these new methodologies require more granularity, hourly or less, for both electricity market data and energy attribute certificates. This can be achieved with so-called granular certificates. This thesis intends to provide some answers to the implications at a corporate level, specifically for their carbon accounting exercises, of adopting these practices. Different industrial and commercial electricity consumer profiles are analyzed in several European countries for 2021 under four different scenarios: base, RE100, 24/7, and emissionality. The results show that using hourly grid carbon intensity, location-based emission can differ from annual calculations up to 7%. In addition, it exemplifies some of the inefficiencies of the current practice of yearly matching of certificates. In 2021, it required less than 1% of a company’s total electricity sourcing costs to certify that they are 100 % renewable, acquiring mainly unbundled certificates. For the case of bundled certificates linked to a specific technology, these costs increased to 2,60 % for the case of the Dutch wind. The 24/7 scenario shows the actual coverage of the renewable contracted sources after the implementation of 24/7 carbon-free electricity matching, ranging from values between 48% and 99 %, depending on the consumption profile, the location, and the contracted renewable sources portfolio. Finally, the emissionality scenario provides the tools to determine where to locate new renewable generation capacity to decrease the emissions as much as possible. The results show that, under specific circumstances, these values can be three times higher. This thesis promotes adopting 24/7 carbon-free electricity practices for attributional carbon accounting methodologies. Nevertheless, its definition should be reviewed to easily include emissionality studies when new carbon-free renewable capacity construction comes from corporations’ green procurement decisions. / Under den rådande klimatkrisen vidtar elbranschen snabba åtgärder för att introducera ny teknik och nya marknadsprocesser som kan bidra till minskade koldioxitutsläpp från elsystemet. Införandet av energiattributcertifikat för mer än tjugo år sedan har gjort det möljigt för konsumenterna att välja vad de vill köpa för el. Detta marknadsinstrument har tillhandahållit ett nytt verktyg för att spåra koldioxidfri el. Det är så företag kan minska sina marknadsbaserade utsläpp enligt Scope 2 Green House Gas Protocol, en praxis som kallas årlig matchning av certifikat. Det finns dock nya trender inom upphandling av grön el som avser att förbättra det nuvarande systemet. Dessa kallas 24/7 koldioxidfri el och emissionalitet. För att skapa ett mervärde kräver dessa nya metoder en ökad granularitet, timbasis eller mindre, för både elmarknadsdata och energiattributcertifikat. Detta kan åstadkommas med så kallade granulära certifikat. Denna rapport avser att ge några svar på konsekvenserna på företagsnivå, specifikt för deras koldioxidredovisningar, av att anta dessa metoder. Olika industriella och kommersiella elkonsumentprofiler analyseras i flera europeiska länder för 2021 under fyra olika scenarier: bas, RE100, 24/7 och emissionalitet. Resultaten visar att då man använder koldioxidsintensitet för elnätet kan de platsberoende utsläppen skilja sig från de årliga beräkningarna med upp till 7%. Dessutom visas exempel på några av ineffektiviteterna i det nuvarande systemet med årlig matchning av certifikat. År 2021 krävdes det mindre än 1% av ett företags totala elkostnad för att intyga att de är 100% förnybara, huvudsakligen med separata certifikat. För paketerade certifikat kopplade till en specifik teknik ökade dessa kostnader till 2,60 % för fallet med holländska vindkraft. 24/7-scenariot visar att efter man implementerat 24/7 koldioxidfri elmatchning så varierar den faktiska täckningen av kontrakterad förnybar produktion mellan 48% och 99% beroende på förbrukningsprofil, lokalisering och vilka förnybara källor som kontrakterats. Slutligen tillhandahåller emissionalitetsscenariet verktygen för att bestämma var ny förnybar produktionskapacitet ska placeras för att minska koldioxidutsläppen så mycket som möjligt. Resultaten visar att under specifika omständigheter kan dessa värden vara tre gånger större. Det här examensarbetet främjar användningen av systemet för 24/7 koldioxidfri el för attributionella koldixodidredovisningsmetoder. Dess definition bör dock ses över för att enkelt inkludera emissionalitetsstudier då ny koldioxidfri av förnybar produktionskapacitet baserat på företags gröna upphandlingsbeslut.
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