870 research outputs found

    Elevated expression of type VII collagen in the skin of patients with systemic sclerosis. Regulation by transforming growth factor-beta.

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    A hallmark of systemic sclerosis (SSc) is the development of tissue fibrosis. Excessive production of several connective tissue components normally present in the dermis, including type I, III, V, and VI collagens as well as fibronectin and proteoglycans, is a consistent finding in the skin of SSc patients. Type VII collagen is a major constituent of anchoring fibrils, present in the skin at the dermal-epidermal basement membrane zone. TGF-beta has been shown to upregulate the expression of the type VII collagen gene. In this study, we assessed the expression of type VII collagen and TGF-beta in the skin of patients with SSc. Indirect immunofluorescence showed an abundance of type VII collagen in the patients\u27 skin, including the dermis. Ultrastructural analysis of SSc skin revealed an abundance of fibrillar material, possibly representing type VII collagen. The increased expression of type VII collagen epitopes was accompanied by the elevated expression of immunodetectable TGF-beta 1 and TGF-beta 2. Dermal fibroblasts cultured from the affected individuals showed a statistically significant (P \u3c 0.02) increase in the expression of type VII collagen at the mRNA level, as detected by reverse transcription-PCR with a mutated cDNA as an internal standard, and increased deposition of the protein as assessed by indirect immunofluorescence. Thus, type VII collagen is abundantly present in SSc patients\u27 dermis, a location not characteristic of its normal distribution, and its aberrant expression may relate to the presence of TGF-beta in the same topographic distribution. The presence of type VII collagen in the dermis may contribute to the tightly bound and indurated appearance of the affected skin in SSc patients

    Elevated Expression of the Genes for Transforming Growth Factor-β1 and Type VI Collagen in Diffuse Fasciitis Associated with the Eosinophilia-Myalgia Syndrome

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    Full-thickness skin biopsies obtained from four patients with rapidly progressive diffuse fasciitis associated with the Eosinophilia-Myalgia syndrome (EMS) were examined for the ex- pression of transforming growth factor-β1 (TGF-β1), type VI collagen, and fibronectin genes employing immunohistochemistry and in situ hybridizations. The immunohistochemical studies demonstrated increased deposition of TGF-β, type VI collagen, and fibronectin epitopes in the extracellular matrix of the fascia in comparison to the adjacent dermis in the same specimens. Increased levels of type VI collagen mRNA, as evidenced by positive in situ hybridization signals with an α2(VI) collagen cDNA, were also found in the fascia in comparison with the dermis. In situ hybridizations of affected fascia with a human sequence-specific TGF-β1 cDNA demonstrated numerous fibroblasts displaying positive hybridization signals indicative of high levels of transcripts for this cytokine. In contrast, no hybridization signal for TGF-β1 was detected in fibroblasts in the adjacent dermis. These findings suggest that TGF-β1 may play an important role in the development of the connective tissue alterations present in EMS-associated diffuse fasciitis

    Etidronate prevents, but does not reverse, ectopic mineralization in a mouse model of pseudoxanthoma elasticum (

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    Pseudoxanthoma elasticum (PXE) and generalized arterial calcification of infancy (GACI) are heritable disorders manifesting with ectopic tissue mineralization. Most cases of PXE and some cases of GACI are caused by mutations in the ABCC6 gene, resulting in reduced plasma pyrophosphate (PPi) levels. There is no effective treatment for these disorders. It has been suggested that administration of bisphosphonates, stable and non-hydrolyzable PPi analogs, could counteract ectopic mineralization in these disorders. In this study we tested the potential efficacy of etidronate, a first generation bisphosphonate, on ectopic mineralization in the muzzle skin of Abcc6-/- mice, a model of PXE. The Abcc6-/- mice received subcutaneous injections of etidronate, 0.283 and 3.40 mg/kg per injection (0.01Ă— and 0.12Ă—), twice a week, in both prevention and reversal studies. Ectopic mineralization in the dermal sheath of vibrissae in muzzle skin was determined by histopathologic analysis and by direct chemical assay for calcium content. Subcutaneous injection of etidronate prevented ectopic mineralization but did not reverse existing mineralization. The effect of etidronate was accompanied by alterations in the trabecular bone microarchitecture, determined by micro-computed tomography. The results suggest that etidronate may offer a potential treatment modality for PXE and GACI caused by ABCC6 mutations. Etidronate therapy should be initiated in PXE patients as soon as the diagnosis is made, with careful monitoring of potential side effects

    Amlexanox Enhances Premature Termination Codon Read-Through in COL7A1 and Expression of Full Length Type VII Collagen: Potential Therapy for Recessive Dystrophic Epidermolysis Bullosa.

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    Recessive dystrophic epidermolysis bullosa (RDEB) is a rare monogenic blistering disorder caused by the lack of functional type VII collagen, leading to skin fragility and subsequent trauma-induced separation of the epidermis from the underlying dermis. A total of 46% of patients with RDEB harbor at least one premature termination codon (PTC) mutation in COL7A1, and previous studies have shown that aminoglycosides are able to overcome RDEB PTC mutations by inducing read-through and incorporation of an amino acid at the PTC site. However, aminoglycoside toxicity will likely prevent widespread clinical application. Here the FDA-approved drug amlexanox was tested for its ability to read-through PTC mutations in cells derived from patients with RDEB. Eight of 12 different PTC alleles responded to treatment and produced full length protein, in some cases more than 50% relative to normal controls. Read-through type VII collagen was readily detectable in cell culture media and also localized to the dermal-epidermal junction in organotypic skin culture. Amlexanox increased COL7A1 transcript and the phosphorylation of UPF-1, an RNA helicase associated with nonsense-mediated mRNA decay, suggesting that amlexanox inhibits nonsense-mediated mRNA decay in cells from patients with RDEB that respond to read-through treatment. This preclinical study demonstrates the potential of repurposing amlexanox for the treatment of patients with RDEB harboring PTC mutation in COL7A1

    Mouse models for pseudoxanthoma elasticum: Genetic and dietary modulation of the ectopic mineralization phenotypes

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    Pseudoxanthoma elasticum (PXE), a heritable ectopic mineralization disorder, is caused by mutations in the ABCC6 gene. Null mice ( Abcc6 -/-) recapitulate the genetic, histopathologic and ultrastructural features of PXE, and they demonstrate early and progressive mineralization of vibrissae dermal sheath, which serves as a biomarker of the overall mineralization process. Recently, as part of a mouse aging study at The Jackson Laboratory, 31 inbred mouse strains were necropsied, and two of them, KK/HlJ and 129S1/SvImJ, were noted to have vibrissae dermal mineralization similar to Abcc6-/- mice. These two strains were shown to harbor a single nucleotide polymorphism (rs32756904) in the Abcc6 gene, which resulted in out-of-frame splicing and marked reduction in ABCC6 protein expression in the liver of these mice. The same polymorphism is present in two additional mouse strains, DBA/2J and C3H/HeJ, with similar reduction in Abcc6 protein levels, yet these mice did not demonstrate tissue mineralization when kept on standard rodent diet. However, all four mouse strains, when placed on experimental diet enriched in phosphate and low in magnesium, developed extensive ectopic mineralization. These results indicate that the genetic background of mice and the mineral composition of their diet can profoundly modulate the ectopic mineralization process predicated on mutations in the Abcc6 gene. These mice provide novel model systems to study the pathomechanisms and the reasons for strain background on phenotypic variability of PXE. © 2014 Li et al

    Recessive mutation in tetraspanin CD151 causes Kindler syndrome-like epidermolysis bullosa with multi-systemic manifestations including nephropathy

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    Epidermolysis bullosa (EB) is caused by mutations in as many as 19 distinct genes. We have developed a next-generation sequencing (NGS) panel targeting genes known to be mutated in skin fragility disorders, including tetraspanin CD151 expressed in keratinocytes at the dermal-epidermal junction. The NGS panel was applied to a cohort of 92 consanguineous families of unknown subtype of EB. In one family, a homozygous donor splice site mutation in CD151 (NM_139029; c.351 + 2T > C) at the exon 5/intron 5 border was identified, and RT-PCR and whole transcriptome analysis by RNA-seq confirmed deletion of the entire exon 5 encoding 25 amino acids. Immunofluorescence of proband's skin and Western blot of skin proteins with a monoclonal antibody revealed complete absence of CD151. Transmission electron microscopy showed intracellular disruption and cell-cell dysadhesion of keratinocytes in the lower epidermis. Clinical examination of the 33-year old proband, initially diagnosed as Kindler syndrome, revealed widespread blistering, particularly on pretibial areas, poikiloderma, nail dystrophy, loss of teeth, early onset alopecia, and esophageal webbing and strictures. The patient also had history of nephropathy with proteinuria. Collectively, the results suggest that biallelic loss-of-function mutations in CD151 underlie an autosomal recessive mechano-bullous disease with systemic features. Thus, CD151 should be considered as the 20th causative, EB-associated gene

    Mediatuen vaikuttavuuden ennakkoarviointi : Loppuraportti

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    Mediatuen vaikuttavuuden ennakkoarviointi -hankkeen tavoitteena on ollut tehdä ennakkoarvio mediatukityöryhmän loppuraportissaan esittämien tukimuotojen vaikuttavuudesta. Arviointi on rajattu kolmeen tukimuotoon: toimituksellinen tuotantotuki, innovaatiotuki ja yhteisömedian tuki. Samalla arviointikysymykset ovat tarkentuneet kolmeen laajempaan kysymykseen: Mitkä ovat olleet mediatuen vaikutukset muissa Pohjoismaissa? Jos Pohjoismainen mediatuki sovelletaan Suomeen, mikä olisi maksetun tuen määrä ja arvioidut vaikutukset? Mitä voidaan oppia tukimuodoista ja niiden teknisistä yksityiskohdista? Arvioinnin yleishavaintona voidaan todeta, että eri tukimuotojen tarkastelu yleisillä elinkeinopoliittisilla yritystuen kriteereillä ei välttämättä johda sidosryhmien kannalta haluttuun lopputulokseen. Pohjoismainen vertailu antaa vahvasti viitteitä, että mediatuet nykyisellä tasolla eivät ole vaikuttavia tai tehokkaita tavanomaisilla yritystalouden mittareilla (mm. liikevaihto, työllisyys ja nimikkeiden määrä). Aineisto kokonaisuutena viittaa vahvasti siihen, että tuet eivät ole vaikuttavia tai tehokkaita, ja niiden kohdistaminen varsinaiseen ongelmaan on hyvin vaikeaa. Näin mediatukia on vaikea perustella tavanomaisilla elinkeinopolitiisilla yritystuen kriteereillä. Tuki voi kuitenkin olla perusteltu muiden yhteiskunnallisten tavoitteiden näkökulmasta

    Regulation of Collagen Gene Expression in Cutaneous Diseases With Dermal Fibrosis: Evidence for Pretranslational Control

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    Dermal fibrosis, characterized by collagen accumulation, is the hallmark of several cutaneous diseases. To examine the mechanisms of collagen deposition in fibrotic skin diseases, fibroblast cultures were established from the skin of patients with progressive systemic sclerosis, morphea, scleredema, familial cutaneous collagenoma, connective tissue nevi of the collagen type, or keloids; these patients served as prototypes of fibrotic skin diseases with varying clinical features and potentially different etiologic factors. Collagen production was assayed by the synthesis of [3H]hydroxyproline, and types I and III procollagen messenger RNA (mRNA) levels were determined by dot blot hybridizations using human type I and type III procollagen-specific cDNA probes. The collagen production in fibroblast cultures from the fibrotic diseases was increased up to 6-fold over the controls, and a relatively good correlation between the collagen production and type I collagen mRNA. levels was noted. The type I/III procollagen mRNA ratio in control fibroblast cultures was 5.9 ± 1.6 (mean ± SD). The corresponding ratio in keloid cell culture was markedly increased, while slightly decreased values were noted in the case of morphea and familial cutaneous collagenoma; the values in other cultures were within the normal range. The results suggest that procollagen production in fibroblast cultures derived from fibrotic skin diseases reflects elevated levels of the corresponding procollagen mRNA. The increased mRNA abundance, suggesting pretranslational control, may result from enhanced transcriptional activity of the corresponding gene or alternatively reflects increased stability of the mRNA molecule

    Financial crises and the attainment of the SDGs: an adjusted multidimensional poverty approach

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    This paper analyses the impact of financial crises on the Sustainable Development Goal of eradicating poverty. To do so, we develop an adjusted Multidimensional Poverty Framework (MPF) that includes 15 indicators that span across key poverty aspects related to income, basic needs, health, education and the environment. We then use an econometric model that allows us to examine the impact of financial crises on these indicators in 150 countries over the period 1980–2015. Our analysis produces new estimates on the impact of financial crises on poverty’s multiple social, economic and environmental aspects and equally important captures dynamic linkages between these aspects. Thus, we offer a better understanding of the potential impact of current debt dynamics on Multidimensional Poverty and demonstrate the need to move beyond the boundaries of SDG1, if we are to meet the target of eradicating poverty. Our results indicate that the current financial distress experienced by many low-income countries may reverse the progress that has been made hitherto in reducing poverty. We find that financial crises are associated with an approximately 10% increase of extreme poor in low-income countries. The impact is even stronger in some other poverty aspects. For instance, crises are associated with an average decrease of government spending in education by 17.72% in low-income countries. The dynamic linkages between most of the Multidimensional Poverty indicators, warn of a negative domino effect on a number of SDGs related to poverty, if there is a financial crisis shock. To pre-empt such a domino effect, the specific SDG target 17.4 on attaining long-term debt sustainability through coordinated policies plays a key role and requires urgent attention by the international community
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