43 resultados para Selective Delivery


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Post-testicular sperm maturation occurs in the epididymis. The ion concentration and proteins secreted into the epididymal lumen, together with testicular factors, are believed to be responsible for the maturation of spermatozoa. Disruption of the maturation of spermatozoa in the epididymis provides a promising strategy for generating a male contraceptive. However, little is known about the proteins involved. For drug development, it is also essential to have tools to study the function of these proteins in vitro. One approach for screening novel targets is to study the secretory products of the epididymis or the G protein-coupled receptors (GPCRs) that are involved in the maturation process of the spermatozoa. The modified Ca2+ imaging technique to monitor release from PC12 pheochromocytoma cells can also be applied to monitor secretory products involved in the maturational processes of spermatozoa. PC12 pheochromocytoma cells were chosen for evaluation of this technique as they release catecholamines from their cell body, thus behaving like endocrine secretory cells. The results of the study demonstrate that depolarisation of nerve growth factor -differentiated PC12 cells releases factors which activate nearby randomly distributed HEL erythroleukemia cells. Thus, during the release process, the ligands reach concentrations high enough to activate receptors even in cells some distance from the release site. This suggests that communication between randomly dispersed cells is possible even if the actual quantities of transmitter released are extremely small. The development of a novel method to analyse GPCR-dependent Ca2+ signalling in living slices of mouse caput epididymis is an additional tool for screening for drug targets. By this technique it was possible to analyse functional GPCRs in the epithelial cells of the ductus epididymis. The results revealed that, both P2X- and P2Y-type purinergic receptors are responsible for the rapid and transient Ca2+ signal detected in the epithelial cells of caput epididymides. Immunohistochemical and reverse transcriptase-polymerase chain reaction (RTPCR) analyses showed the expression of at least P2X1, P2X2, P2X4 and P2X7, and P2Y1 and P2Y2 receptors in the epididymis. Searching for epididymis-specific promoters for transgene delivery into the epididymis is of key importance for the development of specific models for drug development. We used EGFP as the reporter gene to identify proper promoters to deliver transgenes into the epithelial cells of the mouse epididymis in vivo. Our results revealed that the 5.0 kb murine Glutathione peroxidase 5 (GPX5) promoter can be used to target transgene expression into the epididymis while the 3.8 kb Cysteine-rich secretory protein-1 (CRISP-1) promoter can be used to target transgene expression into the testis. Although the visualisation of EGFP in living cells in culture usually poses few problems, the detection of EGFP in tissue sections can be more difficult because soluble EGFP molecules can be lost if the cell membrane is damaged by freezing, sectioning, or permeabilisation. Furthermore, the fluorescence of EGFP is dependent on its conformation. Therefore, fixation protocols that immobilise EGFP may also destroy its usefulness as a fluorescent reporter. We therefore developed a novel tissue preparation and preservation techniques for EGFP. In addition, fluorescence spectrophotometry with epididymal epithelial cells in suspension revealed the expression of functional purinergic, adrenergic, cholinergic and bradykinin receptors in these cell lines (mE-Cap27 and mE-Cap28). In conclusion, we developed new tools for studying the role of the epididymis in sperm maturation. We developed a new technique to analyse GPCR dependent Ca2+ signalling in living slices of mouse caput epididymis. In addition, we improved the method of detecting reporter gene expression. Furthermore, we characterised two epididymis-specific gene promoters, analysed the expression of GPCRs in epididymal epithelial cells and developed a novel technique for measurement of secretion from cells.

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The primary objective of this thesis was to research delivery reliability of mill business unit of a forest industry company, especially timely and quantitative accuracy of sales orders. Delivery reliability is an important factor of customer satisfaction, which has a great influence for success of a company. The secondary objective was to find out reasons for possible problems of delivery reliability and give propositions for improvable performances. The empirical part of the thesis based on reporting database of the forest industry company’s ERP-software and detailed information of the mill system. The delivery reliability results of the mill business unit were compared to delivery reliability of similar mill business unit inside the forest industry company. The research results expressed problems in the supply chain. The delivery reliability reporting should be also developed further. This would advance delivery reliability monitoring. The improvement propositions of the thesis were logistic operation mode estimation, particular benchmarking of the compared mill business unit and more detailed survey on production delivery reliability.

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Human papillomavirus (HPV) infections in mothers are important to consider since pregnancy may affect the outcome of the infection and the mother may transmit HPV to the child. This thesis is part of the 3-year Finnish Family HPV Study on HPV infection dynamics within 329 families. The presence of maternal HPV antibodies and HPV DNA in placenta, umbilical cord blood and breast milk was examined. In addition, genital and oral HR-HPV carriage was studied among mothers with one or two pregnancies. At enrollment, seropositivity to HPV 6, 11, 16, 18 and 45 was recorded in 53 %, 21 %, 35 %, 21 % and 9 % of the mothers, respectively. Age at sexual debut, number of sexual partners, a history of genital warts and antibodies to LR/HR-HPV predicted HR/LR-HPV-seropositivity. During follow-up 27 %, 14 %, 17 %, 17 % and 7 % of the mothers seroconverted to the tested HPV-types, respectively. Decay of HPV-antibodies was rare. The mother’s new pregnancy was of minor impact in the outcome of oral and cervical HR-HPV infections. HPV-DNA was present in 4.2 % and 3.5 % of the placentas and umbilical cord blood samples, and in 4.5 % and 19.7 % of the breast milk samples collected at day 3 and month 2 postpartum, respectively. HPV-positivity in placenta/cord blood was related to a history of abnormal pap-smears or genital warts, and raised the risk of the neonate being HPV-positive at birth. The mode of delivery did not predict the HPVstatus of neonate, placenta, or cord blood. HPV DNA in breast milk was associated with oral HPV status of the father, but not with HPV status of the neonate. The results indicate that exposure to HPV is common and that part of the exposure might take place already early in life. Contrary to the common claim, pregnancy is not a risk factor for HPV.

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This thesis was made for a large forest industry company’s business segment. The purpose of the study was to improve the performance of the order-to-delivery process of the business segment. The study proceeded in three phases. The first phase was to define customer expectations in the market. The second phase was to analyse the performance and the operations of the order-to-delivery process, and to define any challenges or problems in serving the customers. The third and final phase was improving the performance of the order-to-delivery process, within the scope defined by the first two phases. The analysis showed that the delivery reliability is an essential but a challenging issue in the case company’s markets. On delivery reliability standpoint, the most challenging factors were the detected information flow distortions within the company as well as in the whole supply chain, and the lack of horizontal control over the multi-stage process.

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The goal of the study was to analyse orthodontic care in Finnish health centres with special reference to the delivery, outcome and costs of treatment. Public orthodontic care was studied by two questionnaires sent to the chief dental officers of all health centres (n = 276) and to all specialist orthodontists in Finland (n = 146). The large regional variation was mentioned by the orthodontists as the most important factor requiring improvement. Orthodontic practices and outcome were studied in eight Finnish municipal health centres representing early and late timing of treatment. A random sample of 16- and 18-year-olds (n = 1109) living in these municipalities was examined for acceptability of occlusion with the Occlusal Morphology and Function Index (OMFI). In acceptability of occlusion, only minor differences were found between the two timing groups. The percentage of subjects with acceptable morphology was higher among untreated than among treated adolescents. The costs of orthodontic care were estimated among the adolescents with a treatment history. The mean appliance costs were higher in the late, and the mean visit costs higher in the early timing group. The cost-effectiveness of orthodontic services differed among the health centres, but was almost equal in the two timing groups. National guidelines and delegation of orthodontic tasks were suggested as the tools for reducing the variation among the health centres. In the eight health centres, considerable variation was found in acceptability of occlusion and in cost-effectiveness of services. The cost-effectiveness was not directly connected with the timing of treatment.

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The purpose of this thesis is to study organizational core values and their application in practice. With the help of literature, the thesis discusses the implementation of core values and the benefits that companies can gain by doing it successfully. Also, ways in which companies can improve their values’ application to their everyday work are presented. The case company’s value implementation is evaluated through a survey research conducted on their employees. The true power of values lies in their application, and therefore, core values should be the basis for all organizational behavior, integrated into everything a company does. Applying values in practice is an ongoing process and companies should continuously work towards creating a more value-based organizational culture. If a company does this effectively, they will most likely become more successful with stakeholders as well as financially. Companies looking to turn their values into actions should start with a self-assessment. Employee surveys are effective in assessing the current level of value implementation, since employees have valuable, first-hand information regarding the situations and behaviors they face in their everyday work. After the self-assessment, things like management commitment, communication, training, and support are key success factors in value implementation.

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The use of intensity-modulated radiotherapy (IMRT) has increased extensively in the modern radiotherapy (RT) treatments over the past two decades. Radiation dose distributions can be delivered with higher conformality with IMRT when compared to the conventional 3D-conformal radiotherapy (3D-CRT). Higher conformality and target coverage increases the probability of tumour control and decreases the normal tissue complications. The primary goal of this work is to improve and evaluate the accuracy, efficiency and delivery techniques of RT treatments by using IMRT. This study evaluated the dosimetric limitations and possibilities of IMRT in small (treatments of head-and-neck, prostate and lung cancer) and large volumes (primitive neuroectodermal tumours). The dose coverage of target volumes and the sparing of critical organs were increased with IMRT when compared to 3D-CRT. The developed split field IMRT technique was found to be safe and accurate method in craniospinal irradiations. By using IMRT in simultaneous integrated boosting of biologically defined target volumes of localized prostate cancer high doses were achievable with only small increase in the treatment complexity. Biological plan optimization increased the probability of uncomplicated control on average by 28% when compared to standard IMRT delivery. Unfortunately IMRT carries also some drawbacks. In IMRT the beam modulation is realized by splitting a large radiation field to small apertures. The smaller the beam apertures are the larger the rebuild-up and rebuild-down effects are at the tissue interfaces. The limitations to use IMRT with small apertures in the treatments of small lung tumours were investigated with dosimetric film measurements. The results confirmed that the peripheral doses of the small lung tumours were decreased as the effective field size was decreased. The studied calculation algorithms were not able to model the dose deficiency of the tumours accurately. The use of small sliding window apertures of 2 mm and 4 mm decreased the tumour peripheral dose by 6% when compared to 3D-CRT treatment plan. A direct aperture based optimization (DABO) technique was examined as a solution to decrease the treatment complexity. The DABO IMRT technique was able to achieve treatment plans equivalent with the conventional IMRT fluence based optimization techniques in the concave head-and-neck target volumes. With DABO the effective field sizes were increased and the number of MUs was reduced with a factor of two. The optimality of a treatment plan and the therapeutic ratio can be further enhanced by using dose painting based on regional radiosensitivities imaged with functional imaging methods.

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In development of human medicines, it is important to predict early and accurately enough the disease and patient population to be treated as well as the effective and safe dose range of the studied medicine. This is pursued by using preclinical research models, clinical pharmacology and early clinical studies with small sample sizes. When successful, this enables effective development of medicines and reduces unnecessary exposure of healthy subjects and patients to ineffectice or harmfull doses of experimental compounds. Toremifene is a selective estrogen receptor modulator (SERM) used for treatment of breast cancer. Its development was initiated in 1980s when selection of treatment indications and doses were based on research in cell and animal models and on noncomparative clinical studies including small number of patients. Since the early development phase, the treatment indication, the patient population and the dose range were confirmed in large comparative clinical studies in patients. Based on the currently available large and long term clinical study data the aim of this study was to investigate how the early phase studies were able to predict the treatment indication, patient population and the dose range of the SERM. As a conclusion and based on the estrogen receptor mediated mechanism of action early studies were able to predict the treatment indication, target patient population and a dose range to be studied in confirmatory clinical studies. However, comparative clinical studies are needed to optimize dose selection of the SERM in treatment of breast cancer.

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Att övervaka förekomsten av giftiga komponenter i naturliga vattendrag är nödvändigt för människans välmående. Eftersom halten av föroreningar i naturens ekosystem bör hållas möjligast låg, pågår en ständig jakt efter kemiska analysmetoder med allt lägre detektionsgränser. I dagens läge görs miljöanalyser med dyr och sofistikerad instrumentering som kräver mycket underhåll. Jonselektiva elektroder har flera goda egenskaper som t.ex. bärbarhet, låg energiförbrukning, och dessutom är de relativt kostnadseffektiva. Att använda jonselektiva elektroder vid miljöanalyser är möjligt om deras känslighetsområde kan utvidgas genom att sänka deras detektionsgränser. För att sänka detektionsgränsen för Pb(II)-selektiva elektroder undersöktes olika typer av jonselektiva membran som baserades på polyakrylat-kopolymerer, PVC och PbS/Ag2S. Fast-fas elektroder med membran av PbS/Ag2S är i allmänhet enklare och mer robusta än konventionella elektroder vid spårämnesanalys av joniska föroreningar. Fast-fas elektrodernas detektionsgräns sänktes i detta arbete med en nyutvecklad galvanostatisk polariseringsmetod och de kunde sedan framgångsrikt användas för kvantitativa bestämningar av bly(II)-halter i miljöprov som hade samlats in i den finska skärgården nära tidigare industriområden. Analysresultaten som erhölls med jonselektiva elektroder bekräftades med andra analytiska metoder. Att sänka detektionsgränsen m.hj.a. den nyutvecklade polariseringsmetoden möjliggör bestämning av låga och ultra-låga blyhalter som inte kunde nås med klassisk potentiometri. Den verkliga fördelen med att använda dessa blyselektiva elektroder är möjligheten att utföra mätningar i obehandlade miljöprov trots närvaron av fasta partiklar vilket inte är möjligt att göra med andra analysmetoder. Jag väntar mig att den nyutvecklade polariseringsmetoden kommer att sätta en trend i spårämnesanalys med jonselektiva elektroder.

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The impact of menopausal hormone therapy (MHT) on increasing the risk for breast cancer (BC) remains controversial. To understand MHT-elicited cellular breast effects and the potential risks, included with using this therapy, a further investigation into this controversy is the subject of this thesis. In this thesis, to study the effects of estrogen, progestin, androgens and selective estrogen receptor modulators (SERMs), a modified tissue explant culture system was used. The different types of human breast tissues (HBTs) used in this study were normal HBTs, obtained from reduction mammoplasties of premenopausal women (prem-HBTs) or postmenopausal (postm-HBTs) women and peritumoral HBTs (peritum-HBTs) which were obtained from surgeries on postmenopausal BC patients. The explants were cultured up to three weeks in the presence or absence of estradiol (E2), medroxyprogesterone acetate (MPA), testosterone (T), dihydrotestosterone (DHT) and SERMs - ospemifene (OSP), raloxifene (RAL) and tamoxifen (TAM). The cultured HBTs maintained morphological integrity and responded to hormonal treatment in vitro. E2, MPA or E2/MPA increased proliferative activity and was associated with increased cyclin-D1 and caused changes in the cell cycle inhibitors p21 and p27, whereas the androgens T and DHT inhibited proliferation and increased apoptosis in HBT epithelia and opposed E2-stimulated proliferation and cell survival. The postm-HBTs were more sensitive to E2 than prem-HBTs. The effects of OSP, RAL and TAM on HBT epithelium were antiproliferative. E2, androgens and SERMs were associated with marked changes in the proportions of epithelial cells expressing steroid hormone receptors: E2 increased ERα expressing cells and decreased androgen receptor (AR) positive cells, whereas T and DHT had opposite effects. The OSP, RAL and TAM, also decreased a proportion of ERα positive cells in HBT epithelium. At 100 nM, these compounds maintained the relative number of AR positive cells, present at control level, which may partly explain proliferative inhibition. In conclusion, the proliferative activity of E2, in the epithelium of postm-HBTs, is opposed by T and DHT, which suggests that the inclusion of androgens in MHT may decrease the risk for developing BC.

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The evolution of our society is impossible without a constant progress in life-important areas such as chemical engineering and technology. Innovation, creativity and technology are three main components driving the progress of chemistry further towards a sustainable society. Biomass, being an attractive renewable feedstock for production of fine chemicals, energy-rich materials and even transportation fuels, captures progressively new positions in the area of chemical technology. Knowledge of heterogeneous catalysis and chemical technology applied to transformation of biomass-derived substances will open doors for a sustainable economy and facilitates the discovery of novel environmentally-benign processes which probably will replace existing technologies in the era of biorefinary. Aqueous-phase reforming (APR) is regarded as a promising technology for production of hydrogen and liquids fuels from biomass-derived substances such as C3-C6 polyols. In the present work, aqueous-phase reforming of glycerol, xylitol and sorbitol was investigated in the presence of supported Pt catalysts. The catalysts were deposited on different support materials, including Al2O3, TiO2 and carbons. Catalytic measurements were performed in a laboratory-scale continuous fixedbed reactor. An advanced analytical approach was developed in order to identify reaction products and reaction intermediates in the APR of polyols. The influence of the substrate structure on the product formation and selectivity in the APR reaction was also investigated, showing that the yields of the desired products varied depending on the substrate chain length. Additionally, the influence of bioethanol additive in the APR of glycerol and sorbitol was studied. A reaction network was advanced explaining the formation of products and key intermediates. The structure sensitivity in the aqueous-phase reforming reaction was demonstrated using a series of platinum catalysts supported on carbon with different Pt cluster sizes in the continuous fixed-bed reactor. Furthermore, a correlation between texture physico-chemical properties of the catalysts and catalytic data was established. The effect of the second metal (Re, Cu) addition to Pt catalysts was investigated in the APR of xylitol showing a superior hydrocarbon formation on PtRe bimetallic catalysts compared to monometallic Pt. On the basis of the experimental data obtained, mathematical modeling of the reaction kinetics was performed. The developed model was proven to successfully describe experimental data on APR of sorbitol with good accuracy.

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Tankyrases belong to the Diphtheria toxin-like ADP-ribosyltransferase (ARTD) enzyme superfamily, also known as poly(ADP-ribose) polymerases (PARPs). They catalyze a covalent post-translational modification reaction where they transfer ADP-ribose units from NAD+ to target proteins. Tankyrases are involved in many cellular processes and their roles in telomere homeostasis, Wnt signaling and in several diseases including cancers have made them interesting drug targets. In this thesis project, selective inhibition of human tankyrases was studied. A homogeneous fluorescence-based assay was developed to screen the compound libraries. The assay is inexpensive, operationally easy, and performs well according to the statistical analysis. Assay suitability was confirmed by screening a natural product library. Flavone was identified as the most potent inhibitor in the library and this motivated us to screen a larger flavonoid library. Results showed that flavones were indeed the best inhibitor of tankyrases among flavonoids. To further study the structure-activity relationship, a small library of flavones containing single substitution was screened and potency measurements allowed us to generate structure-activity relationship. Compounds containing substitutions at 4´-position were more potent in comparison to other substitutions, and importantly, hydrophobic groups improved isoenzyme selectivity as well as the potency. A flavone derivative containing a hydrophobic isopropyl group (compound 22), displayed 6 nM potency against TNKS1, excellent isoenzyme selectivity and Wnt signaling inhibition. Protein interactions with compounds were studied by solving complex crystal structures of the compounds with TNKS2 catalytic domain. A novel tankyrase inhibitor (IWR-1) was also crystallized in complex with TNKS2 catalytic domain. The crystal structure of TNKS2 in complex with IWR-1 showed that the compound binds to adenosine site and it was the first known ARTD inhibitor of this kind. To date, there is no structural information available about the substrate binding with any of the ARTD family members; therefore NAD+ was soaked with TNKS2 catalytic domain crystals. However, analysis of crystal structure showed that NAD+ was hydrolyzed to nicotinamide. Also, a co-crystal structure of NAD+ mimic compound, EB-47, was solved which was used to deduce some insights about the substrate interactions with the enzyme. Like EB-47, other ARTD1 inhibitors were also shown to inhibit tankyrases. It indicated that selectivity of the ARTD1 inhibitors should be considered as some of the effects in cells could come from tankyrase inhibition. In conclusion, the study provides novel information on tankyrase inhibition and presents new insight into the selectivity and potency of compounds.

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The focus of this thesis is the issues related to the operational purchasing level supply chain process. Due to this limitation, the physical product quality issues do not belong to the primary concerns of this thesis, whereas the bilateral processes between the supplier and the purchasing organizations are of interest. Also, the issues related to the delivery timing are excluded from the study. Because the perspective is on the issues involved in the supply chain operations, the bilateral communication issues between supplier representative and purchaser are also considered.

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Cesarean section (CS) is the most common major surgery performed on women worldwide. CS can save the life of the mother or the fetus, but is associated with the typical complications of any major surgery: hemorrhage, infection, venous thromboembolism and complications of anesthesia, sometimes leading to maternal death. Recently there have been several reports from well resourced countries on increased severe maternal morbidity and even mortality. Increased rates of CS, obesity and older mothers may explain this rise. The aim of this thesis is to study the rates and risk factors of short term maternal complications associated with CS. Also, we compared maternal morbidity by mode of delivery and over time. The complication rates were assessed in a prospective study involving 2496 CS performed in the 12 largest delivery units in Finland in 2005. The rates of severe complications were studied by mode of delivery in a register-based study comparing national cohorts in 1997 and 2002. The impact of several risk factors on severe maternal morbidity by mode of delivery was studied in a register-based study of all singleton deliveries in 2007-2011. In the prospective study, 27% of the women who underwent CS had one or more intraoperative or postoperative complications during their hospital stay, and 10% had a severe complication. In the register-based study the incidence of life-threatening maternal complications was 7.6 in 1000 deliveries. The incidence was lowest for vaginal delivery (VD), followed by instrumental VD and elective CS, and highest in emergency CS. An attempt of VD, including the risks associated with emergency CS, seems to be the safest mode of delivery, even for most high-risk women.

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Depletion of high grade mineral resources, tightening of environmental regulations and the environmental impact of acid mine drainage caused by sulfidic minerals continuously increase the interest in processing tailings and other mine waste. Treating waste requires additional capital and operational input, but the decrease in size and need of tailings ponds and permits decrease the overall costs. Treatment and utilization of the tailings could also bring added revenue by the recovery of valuables. Leaching of metal sulfides is very demanding and time consuming and hence process conditions need to be carefully optimized. The leaching of sulfides is affected by for example the choice of leaching agent, its concentration and temperature, pH, the redox potential, pressure, pulp density and particle size distribution. With reference to the mine case study the leaching of nickel and copper sulfides, especially the primary minerals pentlandite and chalcopyrite were investigated. Leaching behavior and recoveries for nickel, copper and iron were found out by sulfuric and citric acid leaching experiments using tailings samples of high and low sulfur content. Moderate recoveries were obtained and citric acid seemed more attractive. Increase in temperature and decrease in pulp density had positive effect on the recovery and pH was also proven to have a significant effect on the recovery of valuables. The rate determining step was determined through kinetic modeling in case of all valuables separately. Leaching was controlled by diffusion. The investigated multimetal tailing showed moderate potential in recovering of metal valuables from low grade tailing deposits. The process conditions should however be further optimized.