348 research outputs found
Applying mass spectrometric methods to study androgen biosynthesis and metabolism in prostate cancer
Recent development of gas chromatography and liquid chromatography-tandem mass spectrometry (GC-MS/MS, LC-MS/MS) has provided novel tools to define sex steroid concentrations. These new methods overcome several of the problems associated with immunoassays for sex steroids. With the novel MS-based applications we are now able to measure small concentrations of the steroid hormones reliably and with high accuracy in both body fluids and tissue homogenates. The sensitivity of the tandem mass spectrometry assays allows us also for the first time to reliably measure picomolar or even femtomolar concentrations of estrogens and androgens. Furthermore, due to a high sensitivity and specificity of MS technology, we are also able to measure low concentrations of steroid hormones of interest in the presence of pharmacological concentration of other steroids and structurally closely related compounds. Both of these features are essential for multiple preclinical models for prostate cancer. The MS assays are also valuable for the simultaneous measurement of multiple steroids and their metabolites in small sample volumes in serum and tissue biopsies of prostate cancer patients before and after drug interventions. As a result, novel information about steroid hormone synthesis and metabolic pathways in prostate cancer has been obtained. In our recent studies, we have extensively applied a GC-MS/MS method to study androgen biosynthesis and metabolism in VCaP prostate cancer xenografts in mice. In the present review, we shortly summarize some of the benefits of the GC-MS/MS and novel LC-MS/MS assays, and provide examples of their use in defining novel mechanisms of androgen action in prostate cancer.Peer reviewe
Ikääntyneiden asumisratkaisut vuoden 2004 asumis- ja varallisuustutkimuksen valossa
Poikkeavatko ikääntyneiden asuminen ja asumistavoitteet muusta väestöstä: Millaisissa asunnoissa he asuvat? Miten tyytyväisiä he ovat nykyiseen asuntoonsa? Millaisessa asunnossa ikääntyneet haluavat asua ja millaisia tulevaisuuden suunnitelmia heillä on asumisensa suhteen? Ikääntyneiden asumistilannetta ja asumista koskevia ratkaisuja tarkastellaan Tilastokeskuksen vuoden 2004 asumis- ja varallisuustutkimuksen pohjalta. Ikääntyneeksi henkilöksi ymmärretään 55 vuotta täyttäneet sekä yksin että parisuhteessa elävät henkilöt. Asumista tarkastellaan hyvinvoinnin keskeisenä osana ja toisaalta ikääntymistä elämänkaaren aktiivisena vaiheena, jolloin tehdään merkittäviä asumisratkaisuja.
Ikääntyneiden asumistavoitteet ovat monessa suhteessa samankaltaisia kuin muulla väestöllä. Tutkimuksen mukaan varsin monet ikääntyneiden kotitalouksista suunnittelevat muuttoa lähivuosien aikana. Aktiivisimmillaan muuton suunnittelu ajoittuu aiemman yleisen eläkeiän tuntumaan ja 70 ikävuoden myöhäisemmälle puolelle. Muuton kautta ei haeta enää tavoiteasuntoa, vaan muutto voi johtua esimerkiksi lisääntyneestä palvelujen tarpeesta
Uncertainty of Radiometer Calibration Loads and Its Impact on Radiometric Measurements
We present an uncertainty analysis of radiometer calibration.
The procedure can be used to determine the uncertainty
in the nominal brightness temperature of the unknown scene. A
total power radiometer requires frequent calibration with known
reference loads that are connected to the radiometer. Our analysis
includes uncertainties from the radiometer calibration loads and
from the connecting network (CN) that is required to multiplex
calibration loads and scene to the radiometer input. We show the
design and analysis of three calibration loads and how their uncertainties
propagate from load terminals to the radiometer calibration
plane and to the scene. All three loads, including a cryogenic
load, are simple, inexpensive, and show great stability and
accuracy. We give an uncertainty calculation example for our three
calibration loads and for the CN. We validate our model and the
long-term stability of the loads through measurements. The analysis
is done at 52 GHz, but the analysis and the construction of the
loads are generic and easily scalable to other frequencies.</div
Extragonadal LH/hCG action-Not yet time to rewrite textbooks
Gonadotropins are indispensable in both sexes in the regulation of gonadal sex steroid production and gametogenesis. In addition to their well-established classical actions, numerous recent publications have indicated the presence and function of luteinizing hormone/chorionic gonadotropin receptors (LH/hCG-R) in a variety of extragonadal tissues. However, the physiological significance of such effects has remained unclear. We have generated two genetically modified mouse models, one with excessive production of hCG and the other with targeted disruption of LH/hCG-R gene, and used them to address the functions of LH and hCG. Numerous gonadal and extragonadal phenotypes were found in the models with the two extremes of LH/hCG action. However, when the extragonadal effects were scrutinized in greater detail, they all appeared to arise through modification of gonadal function, either through enhanced or inhibited response to LH/hCG stimulation. Hence, further evidence is needed before the extragonadal LH/hCG-R expression can be considered functionally significant.Fil: Pakarainen, Tomi. University of Turku; FinlandiaFil: Ahtiainen, Petteri. University of Turku; FinlandiaFil: Zhang, Fu Ping. University of Helsinki; FinlandiaFil: Rulli, Susana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Poutanen, Matti. University of Turku; FinlandiaFil: Huhtaniemi, Ilpo. University of Turku; Finlandia. IMperial College London; Reino Unid
Analytical dual-link MIMO channel model using correlated correlation matrices
Analytical Multiple-Input Multiple-Output (MIMO) models are often attractive due to their low complexity when analyzing possibilities and limitations in the system. In this paper we outline a a possible dual link extension of an analytical MIMO channel model and investigate its suitability based on measurements of a dual link MIMO scenario. The extension is based on the correlation matrix distance (CMD) as a gauge to generate correlation matrices for the additional links of the multi-link scenario
Radiometric Resolution Analysis and a Simulation Model
Total power radiometer has a simple configuration and the best theoretical resolution. Gain fluctuations and calibration errors, however, can induce severe errors in the solved scene brightness temperature. To estimate the overall radiometer performance we present a numerical simulation tool that can be used to determine the radiometric resolution. Our model considers three main components that degrade the radiometric resolution: thermal noise, 1/f noise and calibration errors. These error sources have long been known to exist, but comprehensive models able to account all these effects quantitatively and accurately in a practical manner have been missing. We have developed a radiometer simulation model that is able to produce radiometer signals that incorporate realistic radiometer effects that show up as noise and other errors in the radiometer video signal. Our simulation tool integrates the fundamental radiometer theories numerically and allows the investigation of different calibration schemes and receiver topologies. The model can be used as a guide for design and optimization as well as for verification of the radiometer performance. Moreover, it can be extended to a much larger and more complex radiometer systems allowing better system level performance estimation and optimization with minimal bread-board implementations. The model mimics real radiometer video data and thus the complete data analysis pipeline can be developed and verified before the real video data is available. In this paper, the model has been applied to a total power radiometer operating in the 52 GHz frequency range.</p
Hyperprolactinemia induced by hCG leads to metabolic disturbances in female mice
The metabolic syndrome is a growing epidemic; it increases the risk for diabetes, cardiovascular disease, fatty liver, and several cancers. Several reports have indicated a link between hormonal imbalances and insulin resistance or obesity. Transgenic (TG) female mice overexpressing the human chorionic gonadotropin β-subunit (hCGβ+ mice) exhibit constitutively elevated levels of hCG, increased production of testosterone, progesterone and prolactin, and obesity. The objective of this study was to investigate the influence of hCG hypersecretion on possible alterations in the glucose and lipid metabolism of adult TG females. We evaluated fasting serum insulin, glucose, and triglyceride levels in adult hCGβ+ females and conducted intraperitoneal glucose and insulin tolerance tests at different ages. TG female mice showed hyperinsulinemia, hypertriglyceridemia, and dyslipidemia, as well as glucose intolerance and insulin resistance at 6 months of age. A 1-week treatment with the dopamine agonist cabergoline applied on 5-week-old hCGβ+ mice, which corrected hyperprolactinemia, hyperandrogenism, and hyperprogesteronemia, effectively prevented the metabolic alterations. These data indicate a key role of the hyperprolactinemia-induced gonadal dysfunction in the metabolic disturbances of hCGβ+ female mice. The findings prompt further studies on the involvement of gonadotropins and prolactin on metabolic disorders and might pave the way for the development of new therapeutic strategies.Fil: Ratner, Laura Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Stevens, Guillermina. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Bonaventura, Maria Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Lux, Victoria Adela R.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Poutanen, Matti. University of Turku; FinlandiaFil: Calandra, Ricardo Saul. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Huhtaniemi, Ilpo T.. University of Turku; FinlandiaFil: Rulli, Susana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentin
Senioritalo ikääntyneen asumisvaihtoehtona. Kysely- ja haastattelututkimus Joensuussa, Kuopiossa ja Tampereella vuonna 2005
Onko senioritalo rakennusalan uusi markkinarako? Mitä se tarjoaa asukkailleen? Ovatko he tyytyväisiä valintaansa? Senioritalot suunnitellaan ikäihmisen esteetöntä liikkumista ja heikentyvää toimintakykyä ajatellen. Senioritaloasumisen lähtökohtana on pyrkimys tukea ikääntyneiden asukkaidensa selviytymistä kodissaan senkin jälkeen, kun tarvitaan liikkumista tukevia apuvälineitä ja kotiin tuotavia palveluja, vaikka taloissa itsessään ei yleensä ole jurikaan palveluja. Ne rakennetaan kuitenkin useimmiten palvelujen läheisyyteen.
Tässä raportissa kuvataan kyselyn ja haastattelujen avulla kolmen erilaisen senioritalon asukkaiden asunnon valintaa ja kokemuksia sekä viihtymistä: Tampereelta on omistusasuntokohde, Kuopiosta asumisoikeustalo ja Joensuusta vuokratalo
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