143 research outputs found
BubR1 promotes Bub3-dependent APC/C inhibition during Spindle Assembly Checkpoint signaling.
The spindle assembly checkpoint (SAC) prevents premature sister chromatid separation during mitosis. Phosphorylation of unattached kinetochores by the Mps1 kinase promotes recruitment of SAC machinery that catalyzes assembly of the SAC effector mitotic checkpoint complex (MCC). The SAC protein Bub3 is a phospho-amino acid adaptor that forms structurally related stable complexes with functionally distinct paralogs named Bub1 and BubR1. A short motif ("loop") of Bub1, but not the equivalent loop of BubR1, enhances binding of Bub3 to kinetochore phospho-targets. Here, we asked whether the BubR1 loop directs Bub3 to different phospho-targets. The BubR1 loop is essential for SAC function and cannot be removed or replaced with the Bub1 loop. BubR1 loop mutants bind Bub3 and are normally incorporated in MCC in vitro but have reduced ability to inhibit the MCC target anaphase-promoting complex (APC/C), suggesting that BubR1:Bub3 recognition and inhibition of APC/C requires phosphorylation. Thus, small sequence differences in Bub1 and BubR1 direct Bub3 to different phosphorylated targets in the SAC signaling cascade
Osteogenesis imperfecta: pregled suvremenih spoznaja o radiologiji koštanoga sustava i nove genetske spoznaje
Osteogenesis imperfecta is a genetically and clinically heterogeneous disorder of bone and connective tissue characterized by osteoporosis, fragile bones, hyperextensible joints, dentinogenesis imperfecta, bluish coloration of the sclerae, and adult-onset hearing loss. Medical history, careful physical examination, radiographic features of fractures, and biochemical analysis of skin collagen are the four cornerstones of accurate diagnosis. As osteogenesis imperfecta affects the whole skeleton, radiologic diagnostic features could be seen on any bone at any age of the patient. A radiology specialist should be aware of subtle changes seen on radiographs of axial skeleton (i.e. skull, spine and pelvic bones) and appendicular skeleton (i.e. long and short bones of extremities) as well as of specific osteogenesis features (i.e. “popcorn” calcifications) and difficult differential diagnosis (i.e. hypertrophic callus formation versus osteosarcoma; child abuse fractures versus true osteogenesis imperfecta). About 300 different mutations have been identified within COL1A1 and COL1A2 genes that encode the chains of type I collagen. More than 90% of these are heterozygous single base pair mutations unique to the affected individuals within families. Depending on the location of the mutation within the collagen gene, these produce a variety of clinical pictures which range from mild (OI type 1), lethal (OI type 2) to severely deforming (OI type 3) and mildly deforming (OI type 4). Each of the four types has a common radiologic appearance that helps in establishing the diagnosis. However, recent findings have confirmed that new genes other than type I collagen could be responsible for three new types of OI (OI type 5; OI type 6 and rhizomelic OI). Here we describe the complexity of the phenotype-genotype correlation in OI, and the recently proposed new classification.Osteogenesis imperfecta (OI) je genetski i klinički heterogena bolest kosti i vezivnoga tkiva s odrednicama: osteoporoza; lomljivost kostiju; labavost zglobova, dentinogenesis imperfecta; plavičaste bjeloočnice i nagluhost u odrasloj dobi. Ključ točne dijagnoze su četiri bitna postupka: precizna anamneza; pažljiv fizikalni pregled; uočavanje radioloških značajka prijeloma i promjena kostiju i biokemijska analiza kolagena kože. Uobičajena je podjela na četiri tipa OI: od blagog (tip 1), letalnog (tip 2) do teško deformirajućeg (tip 3) i umjereno deformirajućeg oblika (tip 4). Svaki od četiri tipa ima zasebne radiološke značajke koje pomažu kod postavljanja točne dijagnoze i klasificiranja. Dijagnostičko-radiološki znaci postoje na cijelom mišićno koštanom sustavu od novorođenačke do kasne životne dobi. Za radiologa je važno prepoznati brojne sićušne i specifične promjene na rendgenogramima aksijalnog (lubanja, kralješnica, zdjelica) i apendikularnog (kosti udova) skeleta. Znaci korisni u diferenciranju osteosarkoma prema stvaranju hipertrofičnog koštanog kalusa kod OI i drugi posebni znaci bolesti, primjerice metafizne “popcorn” kalcifikacije, prepoznaju se dobrom radiološkom obradom. Dosad je otkriveno oko 300 različitih mutacija na COL1A1 i COL1A2 genima odgovornima za oblikovanje lanaca kolagena tip I. Klinička slika OI razlikuje se prema mjestu mutacije na genu za kolagen. Nedavni nalazi su potvrdili da i drugi geni, uz kolagen tip 1, mogu biti odgovorni za nastanak tri nova tipa OI: tip 5; tip 6 i rizomelični tip OI. Nadalje, u tekstu je opisana složenost fenotipske i genotipske korelacije, kao i nedavno predložena nova klasifikacija OI
Osteogenesis imperfecta: pregled suvremenih spoznaja o radiologiji koštanoga sustava i nove genetske spoznaje
Osteogenesis imperfecta is a genetically and clinically heterogeneous disorder of bone and connective tissue characterized by osteoporosis, fragile bones, hyperextensible joints, dentinogenesis imperfecta, bluish coloration of the sclerae, and adult-onset hearing loss. Medical history, careful physical examination, radiographic features of fractures, and biochemical analysis of skin collagen are the four cornerstones of accurate diagnosis. As osteogenesis imperfecta affects the whole skeleton, radiologic diagnostic features could be seen on any bone at any age of the patient. A radiology specialist should be aware of subtle changes seen on radiographs of axial skeleton (i.e. skull, spine and pelvic bones) and appendicular skeleton (i.e. long and short bones of extremities) as well as of specific osteogenesis features (i.e. “popcorn” calcifications) and difficult differential diagnosis (i.e. hypertrophic callus formation versus osteosarcoma; child abuse fractures versus true osteogenesis imperfecta). About 300 different mutations have been identified within COL1A1 and COL1A2 genes that encode the chains of type I collagen. More than 90% of these are heterozygous single base pair mutations unique to the affected individuals within families. Depending on the location of the mutation within the collagen gene, these produce a variety of clinical pictures which range from mild (OI type 1), lethal (OI type 2) to severely deforming (OI type 3) and mildly deforming (OI type 4). Each of the four types has a common radiologic appearance that helps in establishing the diagnosis. However, recent findings have confirmed that new genes other than type I collagen could be responsible for three new types of OI (OI type 5; OI type 6 and rhizomelic OI). Here we describe the complexity of the phenotype-genotype correlation in OI, and the recently proposed new classification.Osteogenesis imperfecta (OI) je genetski i klinički heterogena bolest kosti i vezivnoga tkiva s odrednicama: osteoporoza; lomljivost kostiju; labavost zglobova, dentinogenesis imperfecta; plavičaste bjeloočnice i nagluhost u odrasloj dobi. Ključ točne dijagnoze su četiri bitna postupka: precizna anamneza; pažljiv fizikalni pregled; uočavanje radioloških značajka prijeloma i promjena kostiju i biokemijska analiza kolagena kože. Uobičajena je podjela na četiri tipa OI: od blagog (tip 1), letalnog (tip 2) do teško deformirajućeg (tip 3) i umjereno deformirajućeg oblika (tip 4). Svaki od četiri tipa ima zasebne radiološke značajke koje pomažu kod postavljanja točne dijagnoze i klasificiranja. Dijagnostičko-radiološki znaci postoje na cijelom mišićno koštanom sustavu od novorođenačke do kasne životne dobi. Za radiologa je važno prepoznati brojne sićušne i specifične promjene na rendgenogramima aksijalnog (lubanja, kralješnica, zdjelica) i apendikularnog (kosti udova) skeleta. Znaci korisni u diferenciranju osteosarkoma prema stvaranju hipertrofičnog koštanog kalusa kod OI i drugi posebni znaci bolesti, primjerice metafizne “popcorn” kalcifikacije, prepoznaju se dobrom radiološkom obradom. Dosad je otkriveno oko 300 različitih mutacija na COL1A1 i COL1A2 genima odgovornima za oblikovanje lanaca kolagena tip I. Klinička slika OI razlikuje se prema mjestu mutacije na genu za kolagen. Nedavni nalazi su potvrdili da i drugi geni, uz kolagen tip 1, mogu biti odgovorni za nastanak tri nova tipa OI: tip 5; tip 6 i rizomelični tip OI. Nadalje, u tekstu je opisana složenost fenotipske i genotipske korelacije, kao i nedavno predložena nova klasifikacija OI
Comparison of three methods of DNA extraction from human bones with different degrees of degradation
There is a necessity for deceased identification as a result of many accidents and sometimes bones are the only accessible source of DNA. So far, a universal method that allows for extraction of DNA from materials at different stages of degradation does not exist. The aims of this study were: the comparison of three methods of DNA extraction from bones with different degree of degradation and an evaluation of the usefulness of these methods in forensic genetics. The efficiency of DNA extraction, the degree of extract contamination by polymerase chain reaction (PCR) inhibitors and the possibility of determining the STR loci profile were especially being compared. Nuclear DNA from bones at different states of degradation was isolated using three methods: classical, organic phenol–chloroform extraction, DNA extraction from crystal aggregates and extraction by total demineralisation. Total demineralisation is the best method for most cases of DNA extraction from bones, although it does not provide pure DNA. DNA extraction from aggregates removes inhibitors much better and is also a good method of choice when identity determination of exhumed remains is necessary. In the case of not buried bones (remains found outside) total demineralisation or phenol–chloroform protocols are more efficient for successful DNA extraction
Omics\u27 biomarkers associated with chronic low back pain: Protocol of a retrospective longitudinal study
Introduction
Chronic low back pain (CLBP) produces considerable direct costs as well as indirect burdens for society, industry and health systems. CLBP is characterised by heterogeneity, inclusion of several pain syndromes, different underlying molecular pathologies and interaction with psychosocial factors that leads to a range of clinical manifestations. There is still much to understand in the underlying pathological processes and the non-psychosocial factors which account for differences in outcomes. Biomarkers that may be objectively used for diagnosis and personalised, targeted and cost-effective treatment are still lacking. Therefore, any data that may be obtained at the-omics\u27 level (glycomics, Activomics and genome-wide association studies-GWAS) may be helpful to use as dynamic biomarkers for elucidating CLBP pathogenesis and may ultimately provide prognostic information too. By means of a retrospective, observational, case-cohort, multicentre study, we aim to investigate new promising biomarkers potentially able to solve some of the issues related to CLBP.
Methods and analysis
The study follows a two-phase, 1:2 case-control model. A total of 12 000 individuals (4000 cases and 8000 controls) will be enrolled; clinical data will be registered, with particular attention to pain characteristics and outcomes of pain treatments. Blood samples will be collected to perform-omics studies. The primary objective is to recognise genetic variants associated with CLBP; secondary objectives are to study glycomics and Activomics profiles associated with CLBP.
Ethics and dissemination
The study is part of the PainOMICS project funded by European Community in the Seventh Framework Programme. The study has been approved from competent ethical bodies and copies of approvals were provided to the European Commission before starting the study. Results of the study will be reviewed by the Scientific Board and Ethical Committee of the PainOMICS Consortium. The scientific results will be disseminated through peer-reviewed journals.
Trial registration number
NCT02037789; Pre-results
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