10 resultados para Lh
em Queensland University of Technology - ePrints Archive
Resumo:
The gonadotropin hypothesis proposes that elevated serum gonadotropin levels may increase the risk of epithelial ovarian cancer (EOC). We have studied the effect of treating EOC cell lines (OV207 and OVCAR-3) with FSH or LH. Both gonadotropins activated the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase 1/2 (ERK1/2) pathway and increased cell migration that was inhibited by the MAPK 1 inhibitor PD98059. Both extra- and intracellular calcium ion signalling were implicated in gonadotropin-induced ERK1/2 activation as treatment with either the calcium chelator EGTA or an inhibitor of intracellular calcium release, dantrolene, inhibited gonadotropin-induced ERK1/2 activation. Verapamil was also inhibitory, indicating that gonadotropins activate calcium influx via L-type voltage-dependent calcium channels. The cAMP/protein kinase A (PKA) pathway was not involved in the mediation of gonadotropin action in these cells as gonadotropins did not increase intracellular cAMP formation and inhibition of PKA did not affect gonadotropin-induced phosphorylation of ERK1/2. Activation of ERK1/2 was inhibited by the protein kinase C (PKC) inhibitor GF 109203X as well as by the PKCδ inhibitor rottlerin, and downregulation of PKCδ was inhibited by small interfering RNA (siRNA), highlighting the importance of PKCδ in the gonadotropin signalling cascade. Furthermore, in addition to inhibition by PD98059, gonadotropin-induced ovarian cancer cell migration was also inhibited by verapamil, GF 109203X and rottlerin. Similarly, gonadotropin-induced proliferation was inhibited by PD98059, verapamil, GF 109203X and PKCδ siRNA. Taken together, these results demonstrate that gonadotropins induce both ovarian cancer cell migration and proliferation by activation of ERK1/2 signalling in a calcium- and PKCδ-dependent manner.
Resumo:
During growth of antral ovarian follicles granulosa cells first become associated with a novel type of extracellular matrix, focimatrix, and at larger sizes follicles become either subordinate or dominant. To examine this, bovine subordinate (9.0±s.e.m. 0.4 mm; n=16), partially dominant (12.0±0.6 mm; n=18) and fully dominant (15.0±0.4 mm; n=14) follicles were examined by real time RT-PCR analyses of granulosa cells and by immunohistochemistry of focimatrix. Changes in the expression of FSH receptor, LH receptor, cholesterol side-chain cleavage (CYP11A1), 3β-hydroxysteroid dehydrogenase, aromatase (CYP19A1) and inhibin-α and β-B were observed as expected for follicle sizes examined. After adjusting for size differences, only CYP11A1 was significantly different between the groups, and elevated in dominant follicles. Also after adjusting for differences in size there were no significant differences in expression of focimatrix components collagen type IV α-1 (COL4A1), laminin β-2, nidogen 1 (NID1), and perlecan (HSPG2) or the volume density of NID1 and -2 and HSPG2. The volume density of focimatrix components in laminin 111 was significantly elevated in dominant follicles. Adjusting for analysis of more than one follicle per animal and for multiple correlations, CYP11A1 mRNA levels were highly correlated with the focimatrix genes COL4A1, NID1 and -2 and HSPG2. Thus, focimatrix may potentially regulate CYP11A1 expression, and the regulation of both could be important in follicular dominance.
Resumo:
AIM: Zhi Zhu Wan (ZZW) is a classical Chinese medical formulation used for the treatment of functional dyspepsia that attributed to Spleen-deficiency Syndrome. ZZW contains Atractylodes Rhizome and Fructus Citrus Immaturus, the later originates from both Citrus aurantium L. (BZZW) and Citrus sinensis Osbeck (RZZW). The present study is designed to elucidate disparities in the clinical efficacy of two ZZW varieties based on the pharmacokinetics of naringenin and hesperetin. MEHTOD: After oral administration of ZZWs, blood sample was collected from healthy volunteers at designed time points. Naringenin and hesperetin were detected in plasma by RP-HPLC, pharmacokinetic parameters were processed using mode-independent methods with WINNONLIN. RESULTS: After oral administration of BZZW, both naringenin and hesperetin were detected in plasma, and demonstrated similar pharmacokinetic parameters. Ka was 0.384+/-0.165 and 0.401+/-0.159, T(1/2(ke))(h) was 5.491+/-3.926 and 5.824+/-3.067, the AUC (mg/Lh) was 34.886+/-22.199 and 39.407+/-19.535 for naringenin and hesperetin, respectively. However, in the case of RZZW, only hesperetin was found in plasma, but the pharmacokinetic properties for hesperetin in RZZW was different from that in BZZW. T(max) for hesperetin in RZZW is about 8.515h, and its C(max) is much larger than that of BZZW. Moreover, it was eliminated slowly as it possessed a much larger AUC value. CONCLUSION: The distinct therapeutic orientations of the Chinese medical formula ZZWs with different Fructus Citrus Immaturus could be elucidated based on the pharmacokinetic parameters of constituents after oral administration.
Resumo:
Large-scale purification/separation of bio-substances is a key technology required for rapid production of biological substances in bioengineering. Membrane filtration is a new separation process and has potential to be used for concentration (removal of solvent), desalting (removal of low molecular weight compounds), clarification (removal of particles), and fractionation (protein-protein separation). In this study, we developed an efficient membrane for protein separation based on ceramic nanofibers. Alumina nanofibers were prepared on a porous support and formed large flow passages. The radical changes in membrane structure provided new ceramic membranes with a large porosity (more than 70%) due to the replacement of bulk particles with fine fibers as building components. The pore size had an average of 11 nm and pure water flux was approximately 360 L•h-1•m-2•bar-1. Further surface modification with a self-assembled monolayer of (3-aminopropyl) triethoxysilane enhanced the membrane filtration properties. Characterization with SEM, FTIR, contact angle, and proteins separation tests indicated that the fibril layers uniformly spread on the surface of the porous support. Moreover, the membrane surface was changed from hydrophilic to hydrophobic after silane groups were grafted. It demonstrated that the silane-grafted alumina fiber membrane can reject 100% BSA protein and 92% cellulase protein. It was also able to retain 75% trypsin protein while maintaining a permeation flux of 48 L•h-1•m-2•bar-1.
Resumo:
“Made by Motion” is a collaboration between digital artist Paul Van Opdenbosch and performer and choreographer Elise May; a series of studies on captured motion data used to generating experimental visual forms that reverberate in space and time. The project investigates the invisible forces generated by and influencing the movement of a dancer. Along with how the forces can be captured and applied to generating visual outcomes that surpass simple data visualisation, projecting the intent of the performer’s movements. The source or ‘seed’ comes from using an Xsens MVN - Inertial Motion Capture system to capture spontaneous dance movements, with the visual generation conducted through a customised dynamics simulation. In this first series the visual investigation focused on manipulating the movement date at the instance of capture, capture been the recording of three-dimensional movement as ‘seen’ by the hardware and ‘understood’ through the calibration of software. By repositioning the capture hardware on the body we can effectively change how the same sequence of movements is ‘seen’ by the motion capture system thus generating a different visual result from effetely identical movement. The outcomes from the experiments clearly demonstrates the effectiveness of using motion capture hardware as a creative tool to manipulate the perception of the capture subject, in this case been a sequence of dance movements. The creative work exhibited is a cross-section of the experiments conducted in practice with the first animated work (Movement A - Control) using the motion capture hardware in its default ‘normal’ configuration. Following this is the lower body moved to the upper body (Lb-Ub), right arm moved onto the left arm (Ra-La), right leg moved onto the left leg (Rl-Ll) and finally the left leg moved onto a object that is then held in the left hand (Ll-Pf (Lh)).
Resumo:
This research project aimed to explore students’ perspective on an appropriate mix of online and-face-to-face activities in a master’s programme in library and information science at an Australian university. Identifying aspects that students evaluate as supportive, challenging and efficient in their learning is important for the design of an appropriate mix in blended learning courses. Twenty-three master’s students responded to a questionnaire containing 40 open-ended and closed questions. Applying both statistical and content analysis provides a deeper understanding of students’ responses. Students like the flexibility and the convenience of online learning, but also the possibilities of face-to-face interaction with teachers and peers for building personal learning networks. Students expect an equal quality of learning delivery and criticised the quality of online participation and lecture recordings. Blended learning is an approach that supports a range of learning styles and life styles.
Resumo:
How is your academic institution structured? If you work within a university, then no doubt you are familiar with the use of faculties or perhaps colleges. What about departments or schools? Whatever names or structures are employed, how would you describe the working relationship between academics and professional staff members? As a research scientist and academic over the last twenty years, my appointments have almost always been made through academic departments or schools. In each case, the academic unit has been led by a senior academic manager, such as a chair or head, supported by a dedicated team of professional staff. More recently, however, I have had the opportunity of leading an academic discipline and the experience has led me to reflect more broadly about leadership styles and academic structures within the Australian higher education sector. The written record of this reflection was published last year in the Australian Universities Review (Harkin and Healy, 2013), but I’m pleased to be able to provide a brief synopsis here for the readership of Insights.
Resumo:
Managerial changes to Australian universities have had considerable impact on employees. In this paper we consider some of these changes and apply a theory known as the democratic deficit to them. This theory was developed from the democratic critique of managerialism, as it has been applied in the public sector in countries with Westminster-type political systems. This deficit covers the weakening of accountability through politicisation, the denial of public values through the use of private sector performance practices, and the hollowing out of the state through the contracting out and privatisation of public goods and services, and the redefinition of citizens as customers and clients. We suggest that the increased power of managers, expansion of the audit culture, and the extensive use of contract employment seem to be weakening the democratic culture and role of universities in part by replacing accountability as responsibility with accountability as responsiveness.
Resumo:
This study explores the potential use of empty fruit bunch (EFB) residues from palm oil processing residues, as an alternative feedstock for microbial oil production. EFB is a readily available, lignocellulosic biomass that provides cheaper substrates for oil production in comparison to the use of pure sugars. In this study, potential oleaginous microorganisms were selected based on a multi-criteria analysis (MCA) framework which utilised Analytical Hierarchy Process (AHP) with Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) aided by Geometrical Analysis for Interactive Aid (GAIA). The MCA framework was used to evaluate several strains of microalgae (Chlorella protothecoides and Chlorella zofingiensis), yeasts (Cryptococcus albidus and Rhodotorula mucilaginosa) and fungi (Aspergillus oryzae and Mucor plumbeus) on glucose, xylose and glycerol. Based on the results of PROMETHEE rankings and GAIA plane, fungal strains A. oryzae and M. plumbeus and yeast strain R. mucilaginosa showed great promise for oil production from lignocellulosic hydrolysates. The study further cultivated A. oryzae, M. plumbeus and R. mucilaginosa on EFB hydrolysates for oil production. EFB was pretreated with dilute sulfuric acid, followed by enzymatic saccharification of solid residue. Hydrolysates tested in this study are detoxified liquid hydrolysates (LH) and enzymatic hydrolysate (EH).