A novel extracellular role for tissue transglutaminase in matrix-bound VEGF-mediated angiogenesis

The importance of tissue transglutaminase (TG2) in angiogenesis is unclear and contradictory. Here we show that inhibition of extracellular TG2 protein crosslinking or downregulation of TG2 expression leads to inhibition of angiogenesis in cell culture, the aorta ring assay and in vivo models. In a human umbilical vein endothelial cell (HUVEC) co-culture model, inhibition of extracellular TG2 activity can halt the progression of angiogenesis, even when introduced after tubule formation has commenced and after addition of excess vascular endothelial growth factor (VEGF). In both cases, this leads to a significant reduction in tubule branching. Knockdown of TG2 by short hairpin (shRNA) results in inhibition of HUVEC migration and tubule formation, which can be restored by add back of wt TG2, but not by the transamidation-defective but GTP-binding mutant W241A. TG2 inhibition results in inhibition of fibronectin deposition in HUVEC monocultures with a parallel reduction in matrix-bound VEGFA, leading to a reduction in phosphorylated VEGF receptor 2 (VEGFR2) at Tyr1214 and its downstream effectors Akt and ERK1/2, and importantly its association with b1 integrin. We propose a mechanism for the involvement of matrix-bound VEGFA in angiogenesis that is dependent on extracellular TG2-related activity

Transglutaminase 2 in cartilage homoeostasis: novel links with inflammatory osteoarthritis.

Transglutaminase 2 (TG2) is highly expressed during chondrocyte maturation and contributes to the formation of a mineralised scaffold by introducing crosslinks between extracellular matrix (ECM) proteins. In healthy cartilage, TG2 stabilises integrity of ECM and likely influences cartilage stiffness and mechanistic properties. At the same time, the abnormal accumulation of TG2 in the ECM promotes chondrocyte hypertrophy and cartilage calcification, which might be an important aspect of osteoarthritis (OA) initiation. Although excessive joint loading and injuries are one of the main causes leading to OA development, it is now being recognised that the presence of inflammatory mediators accelerates OA progression. Inflammatory signalling is known to stimulate the extracellular TG2 activity in cartilage and promote TG2-catalysed crosslinking of molecules that promote chondrocyte osteoarthritic differentiation. It is, however, unclear whether TG2 activity aims to resolve or aggravate damages within the arthritic joint. Better understanding of the complex signalling pathways linking inflammation with TG2 activities is needed to identify the role of TG2 in OA and to define possible avenues for therapeutic interventions

A new MRI rating scale for progressive supranuclear palsy and multiple system atrophy: validity and reliability

AIM To evaluate a standardised MRI acquisition protocol and a new image rating scale for disease severity in patients with progressive supranuclear palsy (PSP) and multiple systems atrophy (MSA) in a large multicentre study. METHODS The MRI protocol consisted of two-dimensional sagittal and axial T1, axial PD, and axial and coronal T2 weighted acquisitions. The 32 item ordinal scale evaluated abnormalities within the basal ganglia and posterior fossa, blind to diagnosis. Among 760 patients in the study population (PSP = 362, MSA = 398), 627 had per protocol images (PSP = 297, MSA = 330). Intra-rater (n = 60) and inter-rater (n = 555) reliability were assessed through Cohen's statistic, and scale structure through principal component analysis (PCA) (n = 441). Internal consistency and reliability were checked. Discriminant and predictive validity of extracted factors and total scores were tested for disease severity as per clinical diagnosis. RESULTS Intra-rater and inter-rater reliability were acceptable for 25 (78%) of the items scored (≥ 0.41). PCA revealed four meaningful clusters of covarying parameters (factor (F) F1: brainstem and cerebellum; F2: midbrain; F3: putamen; F4: other basal ganglia) with good to excellent internal consistency (Cronbach α 0.75-0.93) and moderate to excellent reliability (intraclass coefficient: F1: 0.92; F2: 0.79; F3: 0.71; F4: 0.49). The total score significantly discriminated for disease severity or diagnosis; factorial scores differentially discriminated for disease severity according to diagnosis (PSP: F1-F2; MSA: F2-F3). The total score was significantly related to survival in PSP (p<0.0007) or MSA (p<0.0005), indicating good predictive validity. CONCLUSIONS The scale is suitable for use in the context of multicentre studies and can reliably and consistently measure MRI abnormalities in PSP and MSA. Clinical Trial Registration Number The study protocol was filed in the open clinical trial registry (http://www.clinicaltrials.gov) with ID No NCT00211224

p53 and TAp63 promote keratinocyte proliferation and differentiation in breeding tubercles of the zebrafish

p63 is a multi-isoform member of the p53 family of transcription factors. There is compelling genetic evidence that ΔNp63 isoforms are needed for keratinocyte proliferation and stemness in the developing vertebrate epidermis. However, the role of TAp63 isoforms is not fully understood, and TAp63 knockout mice display normal epidermal development. Here, we show that zebrafish mutants specifically lacking TAp63 isoforms, or p53, display compromised development of breeding tubercles, epidermal appendages which according to our analyses display more advanced stratification and keratinization than regular epidermis, including continuous desquamation and renewal of superficial cells by derivatives of basal keratinocytes. Defects are further enhanced in TAp63/p53 double mutants, pointing to partially redundant roles of the two related factors. Molecular analyses, treatments with chemical inhibitors and epistasis studies further reveal the existence of a linear TAp63/p53->Notch->caspase 3 pathway required both for enhanced proliferation of keratinocytes at the base of the tubercles and their subsequent differentiation in upper layers. Together, these studies identify the zebrafish breeding tubercles as specific epidermal structures sharing crucial features with the cornified mammalian epidermis. In addition, they unravel essential roles of TAp63 and p53 to promote both keratinocyte proliferation and their terminal differentiation by promoting Notch signalling and caspase 3 activity, ensuring formation and proper homeostasis of this self-renewing stratified epithelium

After Halberstam : subversion, female masculinity and the subject of heterosexuality

Because female masculinity seems to be at its most threatening whencoupled with lesbian desire, [...]! concentrate on queer female masculinityalmost to the exclusion of heterosexual female masculinity. I have no doubtthat heterosexual female masculinity menaces gender conformity in its ownway, but all too often it represents an acceptable degree of femalemasculinity as compared to the excessive masculinity of the dyke.Judith Halberstam: Female Masculinity.Heterosexuality has been, and continues to be, a controversial subject in feministanalyses surrounding discussions of penetrative sex, marriage, sexual violence, rape,pornography, domestic labour and representation. Although the 1990s and 2000s havewitnessed the proliferation of debates and theorisations of heterosexuality in which itis interrogated and dissected, it is no longer simply condemned and dismissed as itwas by early radical feminism. For early radical feminists, 'heterosexuality was theenemy to be struggled against. Its destruction was a prerequisite for the feministrevolution. Heterosexuality had to go. None of it was retrievable for feministpurposes' (Thompson in Wilkinson & Kitzinger, 1993: 171). Nevertheless, there aretraces of such thought in current theorisations of gender and sexuality.Heterosexuality has not fully shaken its legacy, and is rarely regarded as a source forcelebration and subversion, and/or as exemplary for feminist politics.In this thesis, I look to the work of Lynne Segal, Stevi Jackson and WendyHollway who have contested and problematised radical feminist theorisations ofheterosexuality. There is an emergent desire and call for more celebratorytheorisations of heterosexuality whilst simultaneously there is an ongoing theoreticalscepticism in the emergent queer literature. However, in the 1990s, queer theoryparadoxically began to engage with the subversive potentials of heterosexualityprecisely within the auspices of queer critique, which raised questions on establishedmodels of radicalism. Just as Hollway, Segal and Jackson theorised a feministheterosexuality, ramifications were tangible in queer theory as Calvin Thomas andSegal mobilised a body of work which attempted to theorise subversiveheterosexuality amidst the unproblematised celebration of non-heterosexualities. It ismy intent to conduct this thesis by tracing this simultaneous celebration of nonheterosexualitiesand foreclosure of heterosexuality through the work ofcontemporary queer theory, focussing on the work of Judith 'Jack' Halberstam, authorof the magnificent Female Masculinity (1998). The project intervenes in widerdebates and theoretical developments that seemingly hinder radical readings ofheterosexual identities, and addresses the theoretical discourses of transgression,butchness, queerness and the phallic. Can these tropes be reworked so heterosexualitycan be reconfigured into a sexuality that is tolerated or even viewed as subversive bytheorists, or is heterosexuality doomed to be always theoretically derided?Film: Calamity Jane (1953), Aliens (1986), Johnny Guitar( 1954) and Kill Bill Vol. I& Vol. II (2003 & 2004

Equipping future arts educators for primary schools of the 21st century: an Australian point of view

This article discusses two interrelated themes. First, that arts education plays a valuable role in developing the skills required by successful individuals of an increasingly sophisticated knowledge economy; and second, that arts education programmes in initial primary teacher education courses should be linked to, and compatible with, the needs of future schools. If young people are successfully to develop skills, knowledge and understandings that prepare them as productive citizens of the creative economy, then those enabling that development should understand and in turn be able to demonstrate and foster these capacities