996 resultados para prostate size


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This review outlines current international patterns in prostate cancer incidence and mortality rates and survival, including recent trends and a discussion of the possible impact of prostate-specific antigen (PSA) testing on the observed data. Internationally, prostate cancer is the second most common cancer diagnosed among men (behind lung cancer), and is the sixth most common cause of cancer death among men. Prostate cancer is particularly prevalent in developed countries such as the United States and the Scandinavian countries, with about a six-fold difference between high-incidence and low-incidence countries. Interpretation of trends in incidence and survival are complicated by the increasing impact of PSA testing, particularly in more developed countries. As Western influences become more pronounced in less developed countries, prostate cancer incidence rates in those countries are tending to increase, even though the prevalence of PSA testing is relatively low. Larger proportions of younger men are being diagnosed with prostate cancer and living longer following diagnosis of prostate cancer, which has many implications for health systems. Decreasing mortality rates are becoming widespread among more developed countries, although it is not clear whether this is due to earlier diagnosis (PSA testing), improved treatment, or some combination of these or other factors.

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There is evidence that many heating, ventilating & air conditioning (HVAC) systems, installed in larger buildings, have more capacity than is ever required to keep the occupants comfortable. This paper explores the reasons why this can occur, by examining a typical brief/design/documentation process. Over-sized HVAC systems cost more to install and operate and may not be able to control thermal comfort as well as a “right-sized” system. These impacts are evaluated, where data exists. Finally, some suggestions are developed to minimise both the extent of, and the negative impacts of, HVAC system over-sizing, for example: • Challenge “rules of thumb” and/or brief requirements which may be out of date. • Conduct an accurate load estimate, using AIRAH design data, specific to project location, and then resist the temptation to apply “safety factors • Use a load estimation program that accounts for thermal storage and diversification of peak loads for each zone and air handling system. • Select chiller sizes and staged or variable speed pumps and fans to ensure good part load performance. • Allow for unknown future tenancies by designing flexibility into the system, not by over-sizing. For example, generous sizing of distribution pipework and ductwork will allow available capacity to be redistributed. • Provide an auxiliary tenant condenser water loop to handle high load areas. • Consider using an Integrated Design Process, build an integrated load and energy use simulation model and test different operational scenarios • Use comprehensive Life Cycle Cost analysis for selection of the most optimal design solutions. This paper is an interim report on the findings of CRC-CI project 2002-051-B, Right-Sizing HVAC Systems, which is due for completion in January 2006.

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Brand loyalty is a concept that has garnered considerable interest over recent years from both marketing practitioners and academics alike. While marketers are primarily interested in ways they can generate and increase brand loyalty from their customers, academics strive to conducts research which investigates the antecedents and consequences of customer loyalty (See DeWitt, Nguyen and Marshall 2008; Russell-Bennett, McColl-Kennedy and Coote 2007).

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Bag sampling techniques can be used to temporarily store an aerosol and therefore provide sufficient time to utilize sensitive but slow instrumental techniques for recording detailed particle size distributions. Laboratory based assessment of the method were conducted to examine size dependant deposition loss coefficients for aerosols held in VelostatTM bags conforming to a horizontal cylindrical geometry. Deposition losses of NaCl particles in the range of 10 nm to 160 nm were analysed in relation to the bag size, storage time, and sampling flow rate. Results of this study suggest that the bag sampling method is most useful for moderately short sampling periods of about 5 minutes.

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First-degree relatives of men with prostate cancer have a higher risk of being diagnosed with prostate cancer than men without a family history. The present review examines the prevalence and predictors of testing in first-degree relatives, perceptions of risk, prostate cancer knowledge and psychological consequences of screening. Medline, PsycInfo and Cinahl databases were searched for articles examining risk perceptions or screening practices of first-degree relatives of men with prostate cancer for the period of 1990 to August 2007. Eighteen studies were eligible for inclusion. First-degree relatives participated in prostate-specific antigen (PSA) testing more and perceived their risk of prostate cancer to be higher than men without a family history. Family history factors (e.g. being an unaffected son rather than an unaffected brother) were consistent predictors of PSA testing. Studies were characterized by sampling biases and a lack of longitudinal assessments. Prospective, longitudinal assessments with well-validated and comprehensive measures are needed to identify factors that cue the uptake of screening and from this develop an evidence base for decision support. Men with a family history may benefit from targeted communication about the risks and benefits of prostate cancer testing that responds to the implications of their heightened risk.

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The anti-estrogen treatment for hormone-sensitive breast cancer and the androgen deprivation therapy for prostate cancer can lead to the development of osteoporosis and bone fractures. Metastases associated with prostate and breast cancer can also occur in bone. Bisphosphonates are used in these types of bone dysfunction. Zoledronic acid is the most potent bisphosphonate. In osteoporosis, zoledronic acid inhibits bone reabsorption and increases bone mineral density for at least a year after intravenous administration. The efficacy and safety of zoledronic acid in osteoporosis secondary to hormone-sensitive cancers (prostate and breast), and in the bone metastases associated with these cancers are reviewed.

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Two areas of particular importance in prostate cancer progression are primary tumour development and metastasis. These processes involve a number of physiological events, the mediators of which are still being discovered and characterised. Serine proteases have been shown to play a major role in cancer invasion and metastasis. The recently discovered phenomenon of their activation of a receptor family known as the protease activated receptors (PARs) has extended their physiological role to that of signaling molecule. Several serine proteases are expressed by malignant prostate cancer cells, including members of the kallikreinrelated peptidase (KLK) serine protease family, and increasingly these are being shown to be associated with prostate cancer progression. KLK4 is highly expressed in the prostate and expression levels increase during prostate cancer progression. Critically, recent studies have implicated KLK4 in processes associated with cancer. For example, the ectopic over-expression of KLK4 in prostate cancer cell lines results in an increased ability of these cells to form colonies, proliferate and migrate. In addition, it has been demonstrated that KLK4 is a potential mediator of cellular interactions between prostate cancer cells and osteoblasts (bone forming cells). The ability of KLK4 to influence cellular behaviour is believed to be through the selective cleavage of specific substrates. Identification of relevant in vivo substrates of KLK4 is critical to understanding the pathophysiological roles of this enzyme. Significantly, recent reports have demonstrated that several members of the KLK family are able to activate PARs. The PARs are relatively new members of the seven transmembrane domain containing G protein coupled receptor (GPCR) family. PARs are activated through proteolytic cleavage of their N-terminus by serine proteases, the resulting nascent N-terminal binds intramolecularly to initiate receptor activation. PARs are involved in a number of patho-physiological processes, including vascular repair and inflammation, and a growing body of evidence suggests roles in cancer. While expression of PAR family members has been documented in several types of cancers, including prostate, the role of these GPCRs in prostate cancer development and progression is yet to be examined. Interestingly, several studies have suggested potential roles in cellular invasion through the induction of cytoskeletal reorganisation and expression of basement membrane-degrading enzymes. Accordingly, this program of research focussed on the activation of the PARs by the prostate cancer associated enzyme KLK4, cellular processing of activated PARs and the expression pattern of receptor and agonist in prostate cancer. For these studies KLK4 was purified from the conditioned media of stably transfected Sf9 insect cells expressing a construct containing the complete human KLK4 coding sequence in frame with a V5 epitope and poly-histidine encoding sequences. The first aspect of this study was the further characterisation of this recombinant zymogen form of KLK4. The recombinant KLK4 zymogen was demonstrated to be activatable by the metalloendopeptidase thermolysin and amino terminal sequencing indicated that thermolysin activated KLK4 had the predicted N-terminus of mature active KLK4 (31IINED). Critically, removal of the pro-region successfully generated a catalytically active enzyme, with comparable activity to a previously published recombinant KLK4 produced from S2 insect cells. The second aspect of this study was the activation of the PARs by KLK4 and the initiation of signal transduction. This study demonstrated that KLK4 can activate PAR-1 and PAR-2 to mobilise intracellular Ca2+, but failed to activate PAR-4. Further, KLK4 activated PAR-1 and PAR-2 over distinct concentration ranges, with KLK4 activation and mobilisation of Ca2+ demonstrating higher efficacy through PAR-2. Thus, the remainder of this study focussed on PAR-2. KLK4 was demonstrated to directly cleave a synthetic peptide that mimicked the PAR-2 Nterminal activation sequence. Further, KLK4 mediated Ca2+ mobilisation through PAR-2 was accompanied by the initiation of the extra-cellular regulated kinase (ERK) cascade. The specificity of intracellular signaling mediated through PAR-2 by KLK4 activation was demonstrated by siRNA mediated protein depletion, with a reduction in PAR-2 protein levels correlating to a reduction in KLK4 mediated Ca2+mobilisation and ERK phosphorylation. The third aspect of this study examined cellular processing of KLK4 activated PAR- 2 in a prostate cancer cell line. PAR-2 was demonstrated to be expressed by five prostate derived cell lines including the prostate cancer cell line PC-3. It was also demonstrated by flow cytometry and confocal microscopy analyses that activation of PC-3 cell surface PAR-2 by KLK4 leads to internalisation of this receptor in a time dependent manner. Critically, in vivo relevance of the interaction between KLK4 and PAR-2 was established by the observation of the co-expression of receptor and agonist in primary prostate cancer and prostate cancer bone lesion samples by immunohistochemical analysis. Based on the results of this study a number of exciting future studies have been proposed, including, delineating differences in KLK4 cellular signaling via PAR-1 and PAR-2 and the role of PAR-1 and PAR-2 activation by KLK4 in prostate cancer cells and bone cells in prostate cancer progression.

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Although systemic androgen deprivation prolongs life in advanced prostate cancer, remissions are temporary because patients almost uniformly progress to a state of a castration-resistant prostate cancer (CRPC) as indicated by recurring PSA. This complex process of progression does not seem to be stochastic as the timing and phenotype are highly predictable, including the observation that most androgen-regulated genes are reactivated despite castrate levels of serum androgens. Recent evidence indicates that intraprostatic levels of androgens remain moderately high following systemic androgen deprivation therapy, whereas the androgen receptor (AR) remains functional, and silencing the AR expression following castration suppresses tumor growth and blocks the expression of genes known to be regulated by androgens. From these observations, we hypothesized that CRPC progression is not independent of androgen-driven activity and that androgens may be synthesized de novo in CRPC tumors leading to AR activation. Using the LNCaP xenograft model, we showed that tumor androgens increase during CRPC progression in correlation to PSA up-regulation. We show here that all enzymes necessary for androgen synthesis are expressed in prostate cancer tumors and some seem to be up-regulated during CRPC progression. Using an ex vivo radiotracing assays coupled to high-performance liquid chromatography-radiometric/mass spectrometry detection, we show that tumor explants isolated from CRPC progression are capable of de novo conversion of [(14)C]acetic acid to dihydrotestosterone and uptake of [(3)H]progesterone allows detection of the production of six other steroids upstream of dihydrotestosterone. This evidence suggests that de novo androgen synthesis may be a driving mechanism leading to CRPC progression following castration.

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Visiting a modern shopping center is becoming vital in our society nowadays. The fast growth of shopping center, transportation system, and modern vehicles has given more choices for consumers in shopping. Although there are many reasons for the consumers in visiting the shopping center, the influence of travel time and size of shopping center are important things to be considered towards the frequencies of visiting customers in shopping centers. A survey to the customers of three major shopping centers in Surabaya has been conducted to evaluate the Ellwood’s model and Huff’s model. A new exponent value N of 0.48 and n of 0.50 has been found from the Ellwood’s model, while a coefficient of 0.267 and an add value of 0.245 have been found from the Huff’s model.

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This research quantitatively examines the determinants of board size and the consequence it has on the performance of large companies in Australia. In line with international and the prevalent United States research the results suggest that there is no significant relationship between board size and their subsequent performance. In examining whether more complex operations require larger boards it was found that larger firms or firms with more lines of business tended to have more directors. Data analysis from the research supports the proposition that blockholders could affect management practices and that they enhances performance as measured by shareholder return.