Synthesis, Reactivity and Biological Activity of 17β-HSD1 Inhibitors Based on a Thieno[2,3-d]pryrimidin-4(3H)-one Core

Breast cancer is the most common cancer in women in Western countries. In the early stages of development most breast cancers are hormone-dependent, and estrogens, especially estradiol, have a pivotal role in their development and progression. One approach to the treatment of hormone-dependent breast cancers is to block the formation of the active estrogens by inhibiting the action of the steroid metabolising enzymes. 17beta-Hydroxysteroid dehydrogenase type 1 (17beta-HSD1) is a key enzyme in the biosynthesis of estradiol, the most potent female sex hormone. The 17beta-HSD1 enzyme catalyses the final step and converts estrone into the biologically active estradiol. Blocking 17beta-HSD1 activity with a specific enzyme inhibitor could provide a means to reduce circulating and tumour estradiol levels and thus promote tumour regression. In recent years 17beta-HSD1 has been recognised as an important drug target. Some inhibitors of 17beta-HSD1 have been reported, however, there are no inhibitors on the market nor have clinical trials been announced. The majority of known 17beta-HSD1 inhibitors are based on steroidal structures, while relatively little has been reported on non-steroidal inhibitors. As compared with 17beta-HSD1 inhibitors based on steroidal structures, non-steroidal compounds could have advantages of synthetic accessibility, drug-likeness, selectivity and non-estrogenicity. This study describes the synthesis of large group of novel 17beta-HSD1 inhibitors based on a non-steroidal thieno[2,3-d]pyrimidin-4(3H)-one core. An efficient synthesis route was developed for the lead compound and subsequently employed in the synthesis of thieno[2,3-d]pyrimidin-4(3H)-one based molecule library. The biological activities and binding of these inhibitors to 17beta-HSD1 and, finally, the quantitative structure activity relationship (QSAR) model are also reported. In this study, several potent and selective 17beta-HSD1 inhibitors without estrogenic activity were identified. This establishment of a novel class of inhibitors is a progressive achievement in 17beta-HSD1 inhibitor development. Furthermore, the 3D-QSAR model, constructed on the basis of this study, offers a powerful tool for future 17beta-HSD1 inhibitor development. As part of the fundamental science underpinning this research, the chemical reactivity of fused (di)cycloalkeno thieno[2,3-d]pyrimidin-4(3H)-ones with electrophilic reagents, i.e. Vilsmeier reagent and dimethylformamide dimethylacetal, was investigated. These findings resulted in a revision of the reaction mechanism of Vilsmeier haloformylation and further contributed to understanding the chemical reactivity of this compound class. This study revealed that the reactivity is dependent upon a stereoelectronic effect arising from different ring conformations.

Susceptibility to sulfuryl fluoride and lack of cross-resistance to phosphine in developmental stages of the red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae)

BACKGROUND Our aim was to ascertain the potential of sulfuryl fluoride (SF) as an alternative fumigant to manage phosphine-resistant pests. We tested the susceptibility of all life stages of red flour beetle, Tribolium castaneum (Herbst), to SF and assessed the presence of cross-resistance to this fumigant in phosphine-resistant strains of this species. RESULTS Analysis of dose–response data indicated that the egg was the stage most tolerant to SF under a 48 h exposure period. At LC50, eggs were 29 times more tolerant than other immature stages and adults, and required a relatively high concentration of 48.2 mg L−1 for complete mortality. No significant differences in tolerance to SF were observed among the three larval instars, pupae and adults, and all of these stages were controlled at a low concentration of 1.32 mg L−1. Phosphine-resistant strains did not show cross-resistance to SF. CONCLUSION Our research concluded that the current maximum registered rate of SF, 1500 gh m−3, is adequate to control all the post-embryonic life stages of T. castaneum over a 48 h fumigation period, but it will fail to achieve complete mortality of eggs, indicating the risk of some survival of eggs under this short exposure period. As there is no cross-resistance to SF in phosphine-resistant insects, it will play a key role in managing phosphine resistance in stored-grain insect pests. © 2014 Commonwealth of Australia. Pest Management Science © 2014 Society of Chemical Industry

Measuring the multidimensions of symptoms in people with advanced stages of chronic kidney disease

Chronic kidney disease (CKD) is increasing globally and in Saudi Arabia it affects approximately 8% annual increment of dialysis population. It is associated with a high symptom burden. Previous studies have largely reported on the prevalence of symptoms only in the haemodialysis population. This study examined symptom burden across disease stages and treatment groups in advanced CKD, and their correlation with demographic and clinical factors. Using a cross-sectional design, a convenience sample of 436 patients with CKD was recruited from three hospitals in Saudi Arabia. The CKD Symptom Burden Index (CKD-SBI) was used to measure 32 CKD symptoms. Demographic and clinical data were also collected. Of the sample 75.5% were receiving dialysis (haemodialysis, n = 287; peritoneal dialysis, n = 42) and 24.5% were non-dialysis (CKD stage 4, n = 69; CKD stage 5, n = 38). Average symptom reported was 13.01 ± 7.67. Fatigue and pain were common and burdensome across all symptom dimensions.Approximately one-third of participants experienced sexual symptoms. Dialysis patients reported greater symptom burden, especially patients on haemodialysis. Haemodialysis treatment, older age and being female were independently associated with greater total symptom burden. In conclusion, symptom burden is high among advanced stages of CKD, particularly among those receiving dialysis. Although fatigue, pain and sexual dysfunction are key contributors to symptom burden in CKD, these symptoms are often under-recognised and warrant routine assessment. The CKD-SBI offers a valuable tool to assess symptom burden, leading to the commencement of timely and appropriate interventions.

Insight into the early stages of thermal unfolding of peanut agglutinin by molecular dynamics simulations

Peanut agglutinin is a homotetrameric nonglycosylated protein. The protein has a unique open quaternary structure. Molecular dynamics simulations have been employed follow the atomistic details of its unfolding at different temperatures. The early events of the deoligomerization of the protein have been elucidated in the present study. Simulation trajectories of the monomer as well as those of the tetramer have been compared and the tetramer is found to be substantially more stable than its monomeric counterpart. The tetramer shows retention of most of its.. secondary structure but considerable loss of the tertiary structure at high temperature. e generation of a This observation impies the molten globule-like intermediate in the later stages of deoligomerization. The quaternary structure of the protein has weakened to a large extent, but none of the subunits are separated. In addition, the importance of the metal-binding to the stability of the protein structure has also been investigated. Binding of the metal ions not only enhances the local stability of the metal-ion binding loop, but also imparts a global stability to the overall structure. The dynamics of different interfaces vary significantly as probed through interface clusters. The differences are substantially enhanced at higher temperatures. The dynamics and the stability of the interfaces have been captured mainly by cluster analysis, which has provided detailed information on the thermal deoligomerization of the protein.

Evolution of isolated streamwise vortices in the late stages of boundary layer transition

Experiments were conducted with two, smooth hills, lying well within the boundary layer over a flat plate mounted in a wind tunnel. One hill was shallow, with peak height 1.5 mm and width 50 mm; the other, steep, 3 mm high and 30 mm wide. Since the hills occupied one-half of the tunnel span, streamwise vorticity formed near the hills' edge. At a freestream speed of 3.5 m/s, streaks formed with inflectional wall-normal and spanwise velocity profiles but without effecting transition. Transition, observed at 7.5 m/s, took different routes with the two hills. With the steep hill, streamwise velocity signals exhibited the passage of a wave packet which intensified before breakdown to turbulence. With the shallow hill there was a broad range of frequencies present immediately downstream of the hill. These fluctuations grew continuously and transition occurred within a shorter distance. Since the size of the streamwise vorticity generated at the hill edge is of the order of the hill height, the shallow hill generates vorticity closer to the wall and supports an earlier transition, whereas the steep hill creates a thicker vortex and associated streaks which exhibit oscillations due to their own instability as an additional precursor stage before transition.

Molecular line and continuum studies of the early stages of star formation

New stars form in dense interstellar clouds of gas and dust called molecular clouds. The actual sites where the process of star formation takes place are the dense clumps and cores deeply embedded in molecular clouds. The details of the star formation process are complex and not completely understood. Thus, determining the physical and chemical properties of molecular cloud cores is necessary for a better understanding of how stars are formed. Some of the main features of the origin of low-mass stars, like the Sun, are already relatively well-known, though many details of the process are still under debate. The mechanism through which high-mass stars form, on the other hand, is poorly understood. Although it is likely that the formation of high-mass stars shares many properties similar to those of low-mass stars, the very first steps of the evolutionary sequence are unclear. Observational studies of star formation are carried out particularly at infrared, submillimetre, millimetre, and radio wavelengths. Much of our knowledge about the early stages of star formation in our Milky Way galaxy is obtained through molecular spectral line and dust continuum observations. The continuum emission of cold dust is one of the best tracers of the column density of molecular hydrogen, the main constituent of molecular clouds. Consequently, dust continuum observations provide a powerful tool to map large portions across molecular clouds, and to identify the dense star-forming sites within them. Molecular line observations, on the other hand, provide information on the gas kinematics and temperature. Together, these two observational tools provide an efficient way to study the dense interstellar gas and the associated dust that form new stars. The properties of highly obscured young stars can be further examined through radio continuum observations at centimetre wavelengths. For example, radio continuum emission carries useful information on conditions in the protostar+disk interaction region where protostellar jets are launched. In this PhD thesis, we study the physical and chemical properties of dense clumps and cores in both low- and high-mass star-forming regions. The sources are mainly studied in a statistical sense, but also in more detail. In this way, we are able to examine the general characteristics of the early stages of star formation, cloud properties on large scales (such as fragmentation), and some of the initial conditions of the collapse process that leads to the formation of a star. The studies presented in this thesis are mainly based on molecular line and dust continuum observations. These are combined with archival observations at infrared wavelengths in order to study the protostellar content of the cloud cores. In addition, centimetre radio continuum emission from young stellar objects (YSOs; i.e., protostars and pre-main sequence stars) is studied in this thesis to determine their evolutionary stages. The main results of this thesis are as follows: i) filamentary and sheet-like molecular cloud structures, such as infrared dark clouds (IRDCs), are likely to be caused by supersonic turbulence but their fragmentation at the scale of cores could be due to gravo-thermal instability; ii) the core evolution in the Orion B9 star-forming region appears to be dynamic and the role played by slow ambipolar diffusion in the formation and collapse of the cores may not be significant; iii) the study of the R CrA star-forming region suggests that the centimetre radio emission properties of a YSO are likely to change with its evolutionary stage; iv) the IRDC G304.74+01.32 contains candidate high-mass starless cores which may represent the very first steps of high-mass star and star cluster formation; v) SiO outflow signatures are seen in several high-mass star-forming regions which suggest that high-mass stars form in a similar way as their low-mass counterparts, i.e., via disk accretion. The results presented in this thesis provide constraints on the initial conditions and early stages of both low- and high-mass star formation. In particular, this thesis presents several observational results on the early stages of clustered star formation, which is the dominant mode of star formation in our Galaxy.

Pressure and thermally induced stages of wear in dry sliding of a steel ball against an aluminium-silicon alloy flat

Wear of etched near-eutectic aluminium silicon alloy slid against a steel ball under ambient is explored. The sliding velocity is kept low (0.01 m/s) and the nominal contact pressure is varied in a 15-40 MPa range. Four stages of wear are identified; ultra mild wear, mild wear, severe wear and post severe oxidative wear. The first transition is controlled by the protrusions of silicon particles, projecting out of the aluminium alloy matrix. Once these protrusions disappear under pressure and sliding, oxidation and bulk energy dissipation mechanisms take over to institute transitions to other stages of wear. The phenomenological characteristics of wear stages are explored using a variety of techniques including nanoindentation, focused ion beam milling, electron microscopy, X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS) and optical interferometry. (c) 2010 Elsevier B.V. All rights reserved.

Carotenoids In 3 Stages Of Ripening Of Mango

The distribution of carotenoids, both qualitative and quantitative, during 3 stages of ripening of mango has been studied using chromatographic, spectroscopic and chemical methods. There was an increase in content as well as in number of carotenoids during ripening. The present study showed there were 15, 14 and 17 different carotenoids in the unripe, partially ripe and fully ripe mangoes, respectively. Even though phytofluene (39.26%) was the major carotenoid in the partially ripe mango, β-carotene constituted the major carotenoid in the unripe (37.47%) and fully ripe mango (50.64%). cis-β-Carotene was present only in the fully ripe mango. Only the unripe mango contained ζ-carotene, whereas γ-carotene was present in all the 3 stages of ripening. The major xanthophyll present in the unripe mango was mutatoxanthin (9.44%), whereas auroxanthin constituted the major hydroxylated carotenoid of the partially ripe (5.07%) and fully ripe (10.40%) mangoes. The percent of cryptoxanthin dropped to lower levels during ripening. As ripening proceeded, lutein completely is appeared. There were significant quantities of eaxanthin in the partially ripe and fully ripe mango. Epoxy carotenoids such as 5,6-monoepoxy-β-carotene, mutatochrome, cis-violaxanthin, luteoxanthin, mutatoxanthin and auroxanthin were observed in all 3 stages of ripening.

The RATAS-project, in the Light of 25 Years of Development Towards Computer-Integrated Construction

In smaller countries where the key players in construction IT development tend to know each other personally and where public R&D funding is concentrated to a few channels, IT roadmaps and strategies would seem to have a better chance of influencing development than in the bigger industrial countries. In this paper Finland and the RATAS-project is presented as a historical case illustrating such impact. RATAS was initiated as a construction IT roadmap project in 1985, involving many of the key organisations and companies active in construction sector development. Several of the individuals who took an active part in the project have played an important role in later developments both in Finland and on the international scene. The central result of RATAS was the identification of what is nowadays called Building Information Modelling (BIM) technology as the central issue in getting IT into efficient use in the construction sector. BIM, which earlier was referred to as building product modelling, has been a key ingredient in many roadmaps since and the subject of international standardisation efforts such as STEP and IAI/IFCs. The RATAS project can in hindsight be seen as a forerunner with an impact which also transcended national borders.

Studies on hypomethylation of liver DNA during early stages of chemical carcinogenesis in rat liver

Our finding that the inhibitors of DNA methylation, 5-azacytidine, 5-azadeoxycytidine or adenosine dialdehyde, given after a carcinogen all potentiated initiation suggested that hypomethylation of DNA during repair synthesis of DNA might play a role in the initiation of the carcinogenic process. To examine this aspect further, we have asked the question, do the nodules which develop from initiated cells after promotion with 1% orotic acid exhibit an altered methylation pattern in their DNA? The methylation status of the DNA from nodules has been examined using the restriction endonucleases HpaII/MspI and HhaI which distinguish between methylated and unmethylated cytosines in their nucleotide recognition DNA 5'-CCGG and 5'-GCGC respectively. The proto-oncogenes, c-myc, c-fos and c-Ha-ras, in the DNA were primarily studied in this investigation because of their possible involvement in cell proliferation and/or in cell transformation and tumorigenesis. The results indicate that in the nodule DNA, c-myc and c-fos are hypomethylated in the sequence of CCGG while the c-Ha-ras shows hypomethylation in the alternating GCGC sequence. This methylation pattern seen in the nodule DNA is not found in the DNA of the non-nodular surrounding liver or liver tissue after exposure to promoter or carcinogen alone. It is also not found in the DNA of regenerating liver. It is particularly significant that the methylation patterns in the c-myc and c-Ha-ras regions are similar to those found in several cancer tissues. The results suggest that this methylation pattern is acquired early in the carcinogenic process and raises the question whether it has any bearing on the process.

The effects of organic environmental toxicants on hard tissue formation in developing tooth : An in vitro study in mice

Dioxins are organic toxicants that are known to impair tooth development, especially dental hard tissue formation. The most toxic dioxin congener is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Further, clinical studies suggest that maternal smoking during pregnancy can affect child s tooth development. One of the main components of tobacco smoke is the group of non-halogenated polycyclic aromatic hydrocarbons (PAHs), a representative of which is 7,12-dimethylbenz[a]anthracene (DMBA). Tributyltin (TBT), an organic tin compound, has been shown to impair bone mineralization in experimental animals. In addition to exposure to organic toxicants, a well-established cause for enamel hypomineralization is excess fluoride intake. The principal aim of this thesis project was to examine in vitro if, in addition to dioxins, other organic environmental toxicants, like PAHs and organic tin compounds, have adverse effects on tooth development, specifically on formation and mineralization of the major dental hard tissues, the dentin and the enamel. The second aim was to investigate in vitro if fluoride could intensify the manifestation of the detrimental developmental dental effects elicited by TCDD. The study was conducted by culturing mandibular first and second molar tooth germs of E18 NMRI mouse embryos in a Trowell-type organ culture and exposing them to DMBA, TBT, and sodium fluoride (NaF) and/or TCDD at various concentrations during the secretory and mineralization stages of development. Specific methods used were HE-staining for studying cell and tissue morphology, BrdU-staining for cell proliferation, TUNEL-staining for apoptosis, and QPCR, in situ hybridization and immunohistochemistry for the expressions of selected genes associated with mineralization. This thesis work showed that DMBA, TBT, TCDD and NaF interfere with dentin and enamel formation of embryonic mouse tooth in vitro, and that fluoride can potentiate the harmful effect of TCDD. The results suggested that adverse effects of TBT involve altered expression of genes associated with mineralization, and that DMBA and TBT as well as NaF and TCDD together primarily affect dentin mineralization. Since amelogenesis does not start until mineralization of dentin begins, impaired enamel matrix secretion could be a secondary effect. Dioxins, PAHs and organotins are all liposoluble and can be transferred to the infant by breast-feeding. Since doses are usually very low, developmental toxicity on most of the organs is difficult to indentify clinically. However, tooth may act as an indicator of exposure, since the major dental hard tissues, the dentin and the enamel, are not replaced once they have been formed. Thus, disturbed dental hard tissue formation raises the question of more extensive developmental toxicity.

Developmental analysis of a female-specific 16S rRNA gene from mycetome-associated endosymbionts of a mealybug, Planococcus lilacinus

A clone showing female-specific expression was identified from an embryonic cDNA library of a mealybug, Planococcus lilacinus, In Southern blots this clone (P7) showed hybridization to genomic DNA of females, but not to that of males, However, P7 showed no hybridization to nuclei of either sex, raising the possibility that it was extrachromosomal in origin, In sectioned adult females P7 hybridized to an abdominal organ called the mycetome. The mycetome is formed by mycetocytes, which are polyploid cells originating from the polar bodies and cleavage nuclei that harbour maternally transmitted, intracellular symbionts. Electron microscopy confirmed the presence of symbionts within the mycetocytes, Sequence analysis showed that P7 is a 16S rRNA gene, confirming its prokaryotic origin, P7 transcripts are localized to one pole in young embryos but are found in the pole as well as in the germ band during later stages of development, P7 expression is detectable in young embryos of both sexes but the absence of P7 in third instar and adult males suggests that this gene, and hence the endosymbionts, are subject to sex-specific elimination. Copyright (C) 1997 Elsevier Science Ltd.

Nucleation and growth characteristics of cavities during the early stages of tensile creep deformation in a superplastic zirconia-20 wt% alumina composite

Constant-stress tensile creep experiments on a superplastic 3-mol%-yttria-stabilized tetragonal zirconia composite with 20 wt% alumina revealed that cavities nucleate relatively early during tensile deformation. The number of cavities nucleated increases with increasing imposed stress. The cavities nucleate at triple points associated largely with an alumina grain, and then grow rapidly in a cracklike manner to attain dimensions on the order of the grain facet size. It is suggested that coarser-grained superplastic ceramics exhibit lower ductility due to the ease in formation of such grain boundary facet-cracks and their interlinkage to form a macroscopic crack of critical dimensions.

Differential expression of estrogen receptor alpha in the embryonic adrenal-kidney-gonadal complex of the oviparous lizard, Calotes versicolor (Daud.)

Estrogen signalling is critical for ovarian differentiation in reptiles with temperature-dependent sex determination (TSD). To elucidate the involvement of estrogen in this process, adrenal-kidney-gonadal (AKG) expression of estrogen receptor (ER alpha) was studied at female-producing temperature (FPT) in the developing embryos of the lizard, Calotes versicolor which exhibits a distinct pattern of TSD. The eggs of this lizard were incubated at 31.5 +/- 0.5 degrees C (100% FPT). The torso of embryos containing adrenal-kidney-gonadal complex (AKG) was collected during different stages of development and subjected to Western blotting and immunohistochemistry analysis. The ER alpha, antibody recognized two protein bands with apparent molecular weight similar to 55 and similar to 45 kDa in the total protein extracts of embryonic AKG complex of C. versicolor. The observed results suggest the occurrence of isoforms of ER alpha. The differential expression of two different protein isoforms may reveal their distinct role in cell proliferation during gonadal differentiation. This is the first report to reveal two isoforms of the ER alpha in a reptile during development. Immunohistochemical studies reveal a weak, but specific, cytoplasmic ER alpha immunostaining exclusively in the AKG during late thermo-sensitive period suggesting the responsiveness of AKG to estrogens before gonadal differentiation at FPT. Further, cytoplasmic as well as nuclear expression of ER alpha in the medulla and in oogonia of the cortex (faint activity) at gonadal differentiation stage suggests that the onset of gonadal estrogen activity coincides with sexual differentiation of gonad. Intensity and pattern of the immunoreactions of ER alpha in the medullary region at FPT suggest endogenous production of estrogen which may act in a paracrine fashion to induce neighboring cells into ovarian differentiation pathway. (C) 2014 Elsevier Inc. All rights reserved.