Analysis of the subcellular distribution and trafficking of the insulin-responsive glucose transporter, GLUT4

The translocation of a facilitative glucose transporter, GLUT4, from an intracellular site to the cell surface accounts for the large insulin-dependent increase in glucose transport observed in muscle and adipose tissue. Recent studies have indicated that a large proportion of intracellular GLUT4 is segregated from the recycling endosomal system in a post-endocytic storage compartment in 3T3-L1 adipocytes. However, the nature of this GLUT4 storage compartment, and the mechanism by which GLUT4 reaches the cell surface upon insulin stimulation are poorly understood. Here, I have used Tf-HRP-mediated endosomal ablation analysis to examine the protein composition of the post-endocytic compartment with the aim of further defining the relationship of this compartment to other, well characterised, intracellular membrane structures. The results provide further evidence for the existence of a GLUT4 compartment segregated from the endosomal system, which is devoid of cell surface to endosome recycling markers including the TfR and SCAMPs. The observation that within this compartment, GLUT4 co-localises with TGN marker proteins, gamma-adaptin and the CD-M6PR, suggests that GLUT4 traffics through the TGN as part of its recycling itinerary. I further exploited this technique to examine the translocation of GLUT4 to the cell surface in response to insulin and GTPgammaS. The results indicate that insulin is still capable of stimulating GLUT4 translocation following endosomal ablation under conditions where GTPgammaS-stimulated GLUT4 translocation was effectively inhibited. In addition, both insulin- and GTPgammaS-stimulated GLUT1 translocation were blocked following ablation of the recycling endosomal system. On the basis of these and other data, I propose that insulin stimulates the exocytosis of two distinct compartments, one being the post-endocytic storage compartment and the other being the endosomal system, which may also be stimulated by GTPgammaS. Recent studies have implicated ARF proteins to function as regulators of regulated exocytosis. To investigate the role of ARF proteins in insulin-stimulated GLUT4 translocation, we examined the effect of myristoylated ARF peptides on insulin-stimulated GLUT4 translocation and glucose transport in permeabilised 3T3-L1 adipocytes. A myristoylated peptide corresponding to the N-terminus of ARF6 markedly inhibited insulin-stimulated GLUT4 translocation and 2-deoxy-D-glucose transport, whereas ARF5 and ARF1 peptides were without effect. In addition, an effective inhibitor of PLD, butan-1-ol was observed to have no effect on insulin-stimulated GLUT4 translocation and glucose transport. These results suggest that ARF6 plays a crucial role in insulin-stimulated GLUT4 translocation. However, PLD does not appear to function as a downstream effector of ARF in this event. Finally, I have shown that a chimeric protein comprising the signal sequence of the human growth hormone and HRP (ssHRP) may be targeted to the exocytic pathway and secreted from 3T3-L1 adipocytes. However, due to the time constraints of this study, I was unable to use this HRP probe to ablate the TGN, thus enabling me to investigate the role of this sorting compartment in GLUT4 trafficking

Treatment of periscapular tendinopathy with radiofrequency coblation: a case report

Overuse injuries of the tendon – ‘tendinopathy’ – account for 30%–50% of all sporting injuries and a high proportion of orthopaedic referrals from primary care physicians. Tendinopathies often have a multifactorial aetiology and injury can be due to a combination of both acute and chronic trauma which contributes to loss of tissue integrity and eventual rupture. Our incomplete understanding of the mechanisms surrounding tendon pathophysiology continues to cause difficulties in treatments beyond loading regimes which can be unsuccessful in up to 30% of cases. We describe an uncommon case of tendinopathy affecting the periscapular muscle/tendon unit in a 35-year-old female with persistent pain around the inferior posterior pole of her right scapula. Magnetic resonance imaging findings confirmed oedema of the muscles around the inferior scapular margin in keeping with enthesopathy/tendinopathy and she was treated with radiofrequency coblation to the area. This case highlights radiofrequency ablation as a surgical option should non-operative treatments fail in the rare diagnosis of periscapular tendinopathy

Systematics of the green macroalgal genus Chamaedoris Montague (Siphonocladales), with an emended description of the genus Struvea Sonder

Critical reinvestigation of the four presently recognised species of the green macroalgal genus Chamaedoris (C. auriculata, C. delphinii, C. peniculum and C. orientalis) based on morphological and molecular data reveals that at least one species, C. orientalis, is actually a member of the genus Struvea and is herein transferred to that genus as S. okamurae nom. nov. This has also necessitated a revised circumscription of the genus Struvea. Morphological features traditionally used to delimit the three other species of Chamaedoris (shape of capitulum and number of cells split off from the distal pole of the stipe) are not diagnostic, and the traditional species delineations need to be reassessed. Detailed morphological and morphometric analyses reveal that more subtle differences exist among the three species, including cell dimensions and crystalline cell inclusions. Observations and molecular phylogenetic analyses of new collections over the past 27 years allow us to update knowledge of their biogeographic distributions and determine their relationships with species of the closely related genera Apjohnia, Boodlea, Cladophoropsis, Phyllodictyon and Struvea

Sulfur compounds: From plants to humans and their role in chronic disease prevention

Sulfur is essential for the health of plants and is an indispensable dietary component for human health and disease prevention. Its incorporation into our food supply is heavily reliant upon the uptake of sulfur into plant tissue and our subsequent intake. Dietary requirements for sulfur are largely calculated based upon requirements for the sulfur-containing amino acids (SAA), cysteine and methionine, to meet the demands for synthesis of proteins, enzymes, co-enzymes, vitamins, and hormones. SAA are found in abundance in animal sources and are relatively low in plants. However, some plants, particularly cruciferous and allium vegetables, produce many protective sulfur-containing secondary metabolites, such as glucosinolates and cysteine sulfoxides. The variety and quantity of these sulfur-containing metabolites are extensive and their effects on human health are wide-reaching. Many benefits appear to be related to sulfur’s role in redox biochemistry, protecting against uncontrolled oxidative stress and inflammation; features consistent within cardiometabolic dysfunction and many chronic metabolic diseases of aging. This narrative explores the origins and importance of sulfur, its incorporation into our food supply and dietary sources. It also explores the overarching potential of sulfur for human health, particularly around the amelioration of oxidative stress and chronic inflammation, and subsequent chronic disease prevention

“I\u27m making a positive change in my life”: A mixed method evaluation of a well-being tertiary education unit

Issue Addressed: Mental health disorders (MHDs) are prevalent amongst university students with detrimental impacts on individual students, universities and the wider community. There is an urgent need for proactive and preventative strategies to address the mental health crisis in the university population. This study evaluated the efficacy of a 13-week unit developed to directly educate university students about ways to improve and maintain well-being. Methods: Fifty-eight university students from five disciplines participated in a 13-week elective undergraduate unit “Well-Being Fundamentals for Success” as part of their degree. The Act Belong Commit mental health promotion campaign framework formed the basis of teaching materials. Outcome well-being measures were self-assessed at weeks 1, 6 and 12 using four scales: (1) Warwick-Edinburgh Mental Well-being Scale (WEMWBS); (2) Perceived Stress Scale (PSS); (3) Brief Resilience Scale (BRS) and (4) Mindful Attention Awareness Scale (MAAS). Post-unit group interviews (n = 11) were analysed for key themes. Results: Linear mixed models demonstrated a significant improvement in BRS over the semester; well-being (WEMBS) and mindful attention (MAAS) did increase but not significantly. There was a significant increase in stress (PSS) over the semester. Key themes that emerged from the group interviews were that (1) University life contributes to well-being; (2) University life contributes to stress; (3) The well-being unit helped students see and do things differently; (4) An overall endorsement of the unit. Conclusion: University students’ resilience increased over the semester following participation in a curriculum focused on well-being which featured a combination of theoretical content and experiential workshops. So what? Incorporating mental well-being curriculum into tertiary education is proactive preventive health strategy which may assist with the increasing prevalence of MHD in Australia

Proline-rich tyrosine kinase 2 mediates gonadotropin-releasing hormone signaling to a specific extracellularly regulated kinase-sensitive transcriptional locus in the luteinizing hormone beta-subunit gene

G protein-coupled receptor regulation of gene transcription primarily occurs through the phosphorylation of transcription factors by MAPKs. This requires transduction of an activating signal via scaffold proteins that can ultimately determine the outcome by binding signaling kinases and adapter proteins with effects on the target transcription factor and locus of activation. By investigating these mechanisms, we have elucidated how pituitary gonadotrope cells decode an input GnRH signal into coherent transcriptional output from the LH β-subunit gene promoter. We show that GnRH activates c-Src and multiple members of the MAPK family, c-Jun NH(2)-terminal kinase 1/2, p38MAPK, and ERK1/2. Using dominant-negative point mutations and chemical inhibitors, we identified that calcium-dependent proline-rich tyrosine kinase 2 specifically acts as a scaffold for a focal adhesion/cytoskeleton-dependent complex comprised of c-Src, Grb2, and mSos that translocates an ERK-activating signal to the nucleus. The locus of action of ERK was specifically mapped to early growth response-1 (Egr-1) DNA binding sites within the LH β-subunit gene proximal promoter, which was also activated by p38MAPK, but not c-Jun NH(2)-terminal kinase 1/2. Egr-1 was confirmed as the transcription factor target of ERK and p38MAPK by blockade of protein expression, transcriptional activity, and DNA binding. We have identified a novel GnRH-activated proline-rich tyrosine kinase 2-dependent ERK-mediated signal transduction pathway that specifically regulates Egr-1 activation of the LH β-subunit proximal gene promoter, and thus provide insight into the molecular mechanisms required for differential regulation of gonadotropin gene expression

Studi Volume Lalu Lintas di Jalan Raya Narogong Cileungsi, Kabupaten Bogor, Periode Agustus 2011

Survey of traffic volume is one of the simplest methods to obtain traffic data in order to better understand optimalisation andefficiency so that it can minimize vehicle traffic congestion problems on the highway. The method used is based on descriptive andanalytical methods, which is done is to classify the vehicles in classes manually by counting the number of vehicles per time unitbased on class - class. The purpose of the volume of traffic surveys carried out in the classified Narogong Cullinan Road, Bogorregency during the period August, 2011, results that can be found is the degree of saturation of the highway is still in an acceptablelevel. Analysis of traffic flow at the study site is still under the limit congestion. It is suggested that to reduce the traffic density, thetype of heavy vehicles such as out of the factory operates around the study site between the hours of 10:00 pm to 3:00 am

Treatment outcomes in 1p19q co-deleted/partially deleted gliomasa

AbstractBackground:Radiotherapy with procarbazine, lomustine, and vincristine improves overall survival (OS) in patients with 1p19q co-deleted anaplastic oligodendroglioma/anaplastic oligoastrocytoma.Methods:This retrospective analysis investigated outcomes in patients with 1p19q co-deleted/partially deleted oligodendroglioma, oligoastrocytoma, anaplastic oligodendroglioma, or anaplastic oligoastrocytoma. OS and progression-free survival (PFS) were analyzed using the Kaplan-Meier method and prognostic factors using the Cox proportional hazard model.Results:A total of 106 patients (between December 1997 and December 2013) were included. Median age was 40 years (19-66), 58 were male (55%), Eastern Cooperative Oncology Group performance status was 0 in 80 patients (75%). 1p19q status was co-deleted in 66 (62%), incompletely co-deleted in 27 (25%), and 1p or 19q loss alone in four (4%) and nine (8%) patients, respectively. Isocitrate dehydrogenase-1 R132H mutation was found in 67 of 85 patients with sufficient material. Upfront treatment was given in 72 (68%) patients and temozolomide alone in 52 (49%). Median time to radiotherapy in 47 patients (44%) was 34.7 months and 41.2 months in 9 patients with co-deleted/incompletely co-deleted anaplastic oligodendroglioma/anaplastic oligoastrocytoma who received upfront temozolomide alone. Median OS was not reached and 5-year OS was 91% for all groups (median follow-up, 5.1 years). On multivariable analysis for all patients, receipt of therapy upfront versus none (p=0.04), PS 1 versus 0 (p&lt;0.001) and 1p19q co-deletion/incomplete deletion versus 1p or 19q loss alone (p=0.005) were prognostic for PFS. Isocitrate dehydrogenase-1 status was not prognostic for PFS.Conclusions:With similar survival patterns in low-grade/anaplastic gliomas, molecular characteristics may be more important than histological grade. Longer follow-up and results of prospective trials are needed for definitive guidance on treatment of these patients.</jats:p