bluuebunny/crossref_metadata_2025_split huggingface dataset:
A monoclonal antibody to mammalian angiotensin II AT1 receptor recognizes one of the angiotensin II receptor isoforms expressed by the eel (Anguilla anguilla)
Authors: Marsigliante S , Muscella A , Vilella S , Nicolardi G , Ingrosso L , Ciardo V , Zonno V , Vinson G P , Ho M M , Storelli C 
Published: December 2008

ABSTRACT
Using labelled ligand-binding methods, previous studies have identified specific angiotensin II receptors (Ang II-Rs) in eel liver, kidney and intestine membranes. Isoelectric focusing on polyacrylamide gels also showed that there are two Ang II-R isoforms in eel liver, focusing at isoelectric points (pI) 6·5 and 6·7. These may have different functions. In contrast, eel enterocyte plasma membrane and renal brush border membranes contain only the pI 6·5 form.
To characterize the eel receptors more fully, a newly developed monoclonal antibody (6313/G2) which selectively recognizes the AT1 subtype of mammalian Ang II-R was used. In ligand-binding experiments, the preincubation of eel liver membranes with 6313/G2 antibody eliminated the specific [3,5-3H]Tyr4-Ile5-Ang II binding. Moreover, Ang II—receptor complexes from solubilized liver membranes, which were immunoprecipitated by 6313/G2-coated beads, had a pI of 6·5. In immunoblotting experiments, the antibody recognized the isoform focusing at pI 6·5 in eel intestine and liver preparations, but not the liver pI 6·7 isoform. Immunoblotting of SDS gels showed that the antibody bound to a single protein of molecular mass of 75 kDa in eel liver, gill and kidney and to a doublet of molecular mass of about 74 and 75 kDa in intestinal membrane preparations. Immunocytochemistry of paraffin-embedded and cryostat sections of eel liver, kidney, intestine and gill showed that antibody 6313/G2 bound to uniformly distributed intracellular sites and cell surface membranes in proximal tubular cells, absorptive intestinal cells, hepatocytes and chloride cells. It also stained endothelium and both the longitudinal and circular layers of smooth muscle cells in the intestine.
The data suggest that the previously described Ang II-R from eel liver, kidney and intestine may be similar to the mammalian AT1 subtype.
Molecular cloning and characterization of the yellowtail GH gene and its promoter: a consensus sequence for teleost and avian Pit-1/GHF-1 binding sites
Authors: Ohkubo T , Araki M , Tanaka M , Sudo S , Nakashima K 
Published: December 2008

ABSTRACT
The gene and 5′ flanking promoter region for yellowtail (Seriola quinqueradiata) GH (yGH) have been cloned, sequenced and characterized. The yGH gene spans approximately 4·6 kb and consists of six exons and five introns, as has been observed with rainbow trout, Atlantic salmon and tilapia GH genes. This result suggests that the structure of six exons and five introns is a dominant form in fish GH genes. A typical TATA box exists 26 bp upstream from the transcription start site, and Pit-1/GHF-1 (Pit-1) binding site-homologous regions were found in the promoter region of the yGH gene. In a gel shift assay, however, a single shifted band was detected with the fragments containing a region from −128 to −90 of the yGH 5′ flanking region when they were incubated with yellowtail pituitary nuclear extracts. The bound fragments contained an octamer base sequence similar, but not identical, to mammalian consensus Pit-1 binding element. A consensus octamer sequence is also proposed in this report for the binding of teleost and avian Pit-1 transcription factors.
Cloning of a gar (Lepisosteus osseus) GH cDNA: trends in actinopterygian GH structure
Authors: Rubin D A , Youson J H , Marra L E , Dores R M 
Published: December 2008

ABSTRACT
A cDNA containing the sequence of GH was cloned and sequenced from a pituitary cDNA library for the holostean fish Lepisosteus osseus (common name: gar). The gar GH cDNA contained an open reading frame of 633 nucleotides and a 3′ untranslated region (including the terminal codon TAG) of 1058 nucleotides. The overall length of the gar GH cDNA including leader sequence, signal sequence, hormone sequence and 3′ untranslated region was 1713 nucleotides. Thus, the gar GH cDNA is the largest vertebrate GH cDNA yet cloned. A comparison of GH sequences from ancient (holostean fishes — gar and bowfin; one chondrostean fish — the Russian sturgeon) and more modern (27 species of teleosts) members of class Actinopterygii indicate that members of this class have maintained many of the invariant residues deemed necessary for GH folding motifs (intramolecular relationships) observed in mammals.
The roles of adenosine 3′,5′-cyclic monophosphate-dependent protein kinase A and protein kinase C in stimulus-secretion coupling in AtT-20 cells
Authors: McFerran B W , Guild S B 
Published: December 2008

ABSTRACT
The ACTH-secreting mouse AtT-20/D16–16 anterior pituitary tumour cell line was used to study adenosine 3′,5′-cyclic monophosphate (cAMP)-dependent protein kinase A (PKA) and protein kinase C (PKC) involvement in stimulus-secretion coupling pathways. In permeabilised AtT-20 cells under calcium ion-free conditions, forskolin (10 μm), CRH-41 (100 nm), guanosine 5′-O-(3-thiotriphosphate) (GTP-γ-S; 100 μm) but not mastoparan (10 μm) stimulated cAMP accumulation. Measurement of ACTH secretion under identical incubation conditions revealed that GTP-γ-S and mastoparan significantly stimulated ACTH secretion but forskolin and CRH-41 did not. This dissociates cAMP accumulation from ACTH secretion under calcium ion-free conditions and indicated that the effects of mastoparan and GTP-γ-S on ACTH secretion are not mediated by cAMP production. Calcium ions (1 nm to 1 mm) stimulated ACTH secretion from electrically permeabilised cells in a concentration-dependent manner. cAMP (100μm) and phorbol 12-myristate 13-acetate (PMA; 100 nm) synergistically enhanced the response to calcium ions. cAMP did not stimulate ACTH secretion in the absence of calcium ions nor did it alter the concentrations at which calcium stimulated ACTH secretion. This suggests that stimulation of ACTH secretion via the calcium-dependent pathway is necessary before any cAMP-mediated enhancement of secretion is manifest. PMA, however, did stimulate ACTH secretion in the absence of calcium ions, indicating distinct mechanisms for PKC-evoked secretion. Co-incubation with cAMP and PMA did not exceed the secretory response obtained with the combination of PMA and calcium ions. CRH-41 (1 pm to 100 nm) and forskolin (1 nm to 100μm) stimulated ACTH secretion from intact cells in a concentration-dependent manner. Co-incubation with PMA (100 nm) further enhanced the ACTH response to CRH-41 and forskolin; the effects were simply additive. The present study indicates that there are distinct roles for PKA and PKC in stimulussecretion coupling in AtT-20 cells. The PKA-dependent pathway, acting in concert with the calcium messenger system, serves as part of the stimulus-secretion coupling pathway by which activation of CRH-41 receptors control ACTH secretion. The PKC-dependent pathway, in contrast, seems to be independent of the calcium messenger system and may represent a separate control mechanism of ACTH secretion.
Insect cells infected with a recombinant baculovirus express both O- and N-glycosylated forms of the rat glycoprotein hormone α-subunit
Authors: Delahaye R , Berreur P , Salesse R , Counis R 
Published: December 2008

ABSTRACT
Glycoprotein hormones LH, FSH, TSH and chorionic gonadotrophin are heterodimers composed of two non-covalently associated subunits, a common α- and a specific β-subunit. A recombinant baculo-virus containing a cDNA encoding the α-subunit of rat glycoprotein hormones was constructed. Viral-infected cells expressed, 48 h post infection, 7–10mg immunoreactive α-glycopolypeptide/6×108 cells, of which 65·6% was able to associate with native LHβ and formed a biologically active heterodimeric hormone that bound to testicular receptors. The treatment with specific glycanases showed that the recombinant α-subunit was produced as two differently glycosylated forms; an Mr 23 000 form which contained exclusively N-linked carbohydrate units and another of Mr 25 000 which appeared to contain additional O-linked carbohydrate. Data demonstrated that the α-subunit was expressed by insect cells in a manner similar to that by mammalian pituitary gonadotropes producing both the N- and O-glycosylated forms although only the N-glycosylated α-subunit is known to be capable of associating with the β-subunit.
The growth hormone-dependent decrease in hepatic fatty acid synthase mRNA is the result of a decrease in gene transcription
Authors: Donkin S S , McNall A D , Swencki B S , Peters J L , Etherton T D 
Published: December 2008

ABSTRACT
The present study was conducted to determine the chronic effects of porcine growth hormone administration on fatty acid synthase (FAS) mRNA abundance and gene transcription in growing rats. Growth hormone treatment increased growth rate approximately 27% (P<0·01). Porcine growth hormone decreased FAS mRNA levels by 55%. The reduction in FAS mRNA was due to a marked decrease in transcription of the FAS gene (decreased by 80%). In contrast, porcine growth hormone did not affect mRNA abundance or transcription rate of another insulin-regulated gene, phosphoenolpyruvate carboxykinase. In summary, our results have established that chronic treatment with growth hormone decreases FAS mRNA by decreasing the transcription rate of the gene. Furthermore, they suggest that the effects of growth hormone are specific and are not mediated by general changes in insulin-responsive gene expression in liver.
Molecular cloning of the cDNAs encoding pituitary glycoprotein hormone α- and gonadotropin IIβ-subunits of the Japanese eel, Anguilla japonica, and increase in their mRNAs during ovarian development induced by injection of chum salmon pituitary homogenate
Authors: Nagae M , Todo T , Gen K , Kato Y , Young G , Adachi S , Yamauchi K 
Published: December 2008

ABSTRACT
cDNAs encoding the glycoprotein hormone α- and gonadotropin (GTH) IIβ-subunits of Japanese eel (Anguilla japonica) pituitary were cloned using the polymerase chain reaction. The nucleotide sequence of the glycoprotein hormone α-subunit cDNA was 364 base pairs (bp) long, encoding 117 amino acids, and that of the GTH IIβ-subunit cDNA was 433 bp long, encoding 140 amino acids. The deduced amino acid sequence of each mature subunit showed high homology with those of other teleosts, indicating that the structure of GTH subunits has been conserved during the evolution of teleosts. Changes in the expression of these subunit genes during ovarian development induced artificially by the injection of chum salmon pituitary homogenate were examined using Northern blot analysis. Glycoprotein hormone α-subunit mRNA increased almost linearly during ovarian development, whereas GTH IIβ-subunit mRNA was detected only at the late vitellogenic and migratory nucleus stages. These data indicate that eel GTH II is synthesized mainly at the late vitellogenic and migratory nucleus stages, and suggest that GTH II plays an important role in final oocyte maturation of Japanese eel. Changes in the expression of glycoprotein hormone α- and GTH IIβ-subunits mRNA correlate with the serum estradiol-17β (E2) and testosterone profile during ovarian development. The increase in mRNA of both subunits is probably due to positive feedback of E2 and testosterone produced by ovarian follicles in response to the GTH contained in chum salmon pituitary homogenate.
Novel and sensitive detection systems for the vitamin D receptor — in situ-reverse transcriptase-polymerase chain reaction and immunogold cytochemistry
Authors: Mee A P , Davenport L K , Hoyland J A , Davies M , Mawer E B 
Published: December 2008

ABSTRACT
The receptor for the active metabolite of vitamin D, 1,25(OH)2D3, known as the vitamin D receptor (VDR), belongs to the steroid hormone nuclear receptor superfamily. We have developed novel methods for detection of VDR mRNA and protein within a human promyelomonocytic cell line, HL-60.
Using the newly developed technique of in situ-reverse transcriptase-polymerase chain reaction (IS-RT-PCR), low levels of VDR mRNA could be amplified and demonstrated unequivocally within these cells, and also within a human kidney proximal tubule cell line, CL-8. Use of a novel immunogold cytochemical technique has allowed clear and sensitive detection of VDR protein expression within the HL-60 cells.
Further development of IS-RT-PCR has allowed us to apply this technique to tissue sections. We have shown clear amplification of VDR transcripts within sections of formalin-fixed paraffin-embedded human kidney and liver.
These techniques will be useful to localise specifically the VDR within cell types that contain low levels of mRNA and protein, and will permit further investigation of the role played by 1,25(OH)2D3 in cellular regulatory mechanisms.
An alternative splice variant of the mouse TRH receptor mRNA is the major form expressed in the mouse pituitary gland
Authors: Jones K E , Brubaker J H , Chin W W 
Published: December 2008

ABSTRACT
The sequences of the mouse and rat TRH receptors (TRH-Rs) show 94% similarity at the protein level. However, they differ significantly at their carboxy terminals, i.e. the mouse TRH-R ends with an asparagine at position 393 while, in the rat, residue 393 is lysine and an additional 19 amino acids are added before the first stop codon. In the mouse cDNA, the sequence encoding these additional amino acids is located 224 bp downstream in the 3′ untranslated region (3′UT). As the mouse TRH-R was cloned from thyrotrope-derived TtT97 tissue and the rat TRH-R from lactotrope-derived GH cell lines, we have investigated whether this difference at the carboxyterminus represents a species-specific or cell type-specific pattern of TRH-R expression. Total RNA was isolated from mouse pituitary and TtT97 tissue, and rat pituitary and GH3 cells. Reverse transcription PCR analysis was performed using primers that would generate DNA fragments including the stop codon in either the mouse or the rat TRH-R and, in the mouse form, the extra 224 bp of 3′UT. This would generate a product of 234 bp from the rat sequence and 441 bp from the mouse sequence. In rat pituitary and GH3 cDNA, PCR generated the expected 234 bp product but not a band representing the mouse sequence. In both mouse pituitary and TtT97 cDNA, neither the expected 441 bp nor the 234 bp fragments were amplified; instead a larger, 829 bp, product was generated. Sequence analysis revealed a 388 bp insertion at position 1663 in the 3′UT compared with the published mouse TRH-R sequence. Ribonuclease protection analysis using this 829 bp fragment as a probe showed that this sequence represented the major TRH-R mRNA species in mouse pituitary and TtT97 RNA. A genomic clone containing this region of the mouse TRH-R gene was isolated and analysis of the sequence in this region revealed that this longer form of the mouse TRH-R could be generated by alternative splicing.
In summary, we have shown that the carboxyterminal differences between the mouse and rat TRH-Rs are species-specific rather than cell typespecific, and that the major TRH-R mRNA expressed in mouse pituitary contains an additional 388 bp of 3′UT compared with the published sequence. As a region in the 3′UT of the published mTRH-R sequence has been shown to be important for stability of this mRNA, this additional 3′UT sequence could have major effects on the regulation and stability of the mouse TRH-R mRNA.
Selenoenzyme expression in thyroid and liver of second generation selenium- and iodine-deficient rats
Authors: Mitchell J H , Nicol F , Beckett G J , Arthur J R 
Published: December 2008

ABSTRACT
The stimulation of thyroid hormone synthesis in iodine deficiency may increase the requirement for the selenoproteins which are involved in thyroid hormone synthesis in the thyroid gland. Selenoenzyme activity and expression were investigated in the thyroid and liver of second generation selenium-and/or iodine-deficient rats. Selenium deficiency caused substantial decreases in hepatic seleniumcontaining type I iodothyronine deiodinase (ID-I) and cytosolic glutathione peroxidase (cGSHPx) activities and mRNA abundances, but phospholipid hydroperoxide glutathione peroxidase (phGSHPx) activity was only 55% of selenium-supplemented control levels, despite the absence of change in its mRNA abundance. Selenoenzyme mRNA concentrations were maintained at control levels in thyroid glands from the selenium-deficient rat pups. Despite this, a differential effect was observed in selenoenzyme activities: ID-I activity was decreased to 61%, cGSHPx activity to 45% and phGSHPx to 29% of that in selenium-adequate controls. In iodine-deficient thyroid glands, mRNA levels were increased 2·2, 50 and 2·8 times for ID-I, cGSHPx and phGSHPx respectively. ID-I and cGSHPx enzyme activities were also increased but the activity of phGSHPx was decreased despite the high mRNA abundance. Thyroid selenoprotein mRNA levels were also increased in combined selenium and iodine deficiency but again there were differential effects on enzyme activities, with ID-I activity increased, cGSHPx unchanged and phGSHPx decreased. Thus, iodine deficiency may produce an oxidant stress on the thyroid gland, increasing the requirement for selenium to maintain selenoenzyme activity. When dietary supplies of selenium are limiting, thyroid selenoprotein mRNA levels are increased to compensate for overall lack of the micronutrient. Furthermore, there is a preferential supply of available selenium to ID-I and cGSHPx to allow maintenance of thyroid function.
Regulation of 11β-hydroxysteroid dehydrogenase type 2 activity and mRNA in human choriocarcinoma cells
Authors: Pasquarette M M , Stewart P M , Ricketts M L , Imaishi K , Mason J I 
Published: December 2008

ABSTRACT
The type 2 isoform of 11 β-hydroxysteroid dehydrogenase (11β-HSD2), which catalyzes the conversion of cortisol to hormonally inactive cortisone in man, is principally expressed in the placenta and mineralocorticoid target tissues, kidney and colon. To date, few studies have addressed the regulation of this novel 11β-HSD2 isoform. We have characterized the nature and regulation of the 11β-HSD activity expressed in a human cytotrophoblastic cell line, the JEG-3 choriocarcinoma cell. The 11β-HSD activity in JEG-3 cell homogenates required NAD+ as cofactor with NADP ineffective and demonstrated a high affinity for cortisol (apparent Km 31 nm). Incubation of JEG-3 cells with forskolin and dibutyryl cyclic AMP increased 11β-HSD2 activity several-fold in a time-dependent manner, while treatment with phorbol ester had little, if any, effect on 11β-HSD2 activity. Northern blot analysis of RNA isolated from JEG-3 cells after these treatments demonstrated a marked increase in a 1·9 kb 11β-HSD2 mRNA species in cells treated with forskolin for 24 h. We conclude that 11β-HSD2 is regulated by activation of the protein kinase A pathway, but not the protein kinase C pathway in human choriocarcinoma cells, and that this regulation occurs at a pretranslational level. JEG-3 cells provide an excellent model for further studies on the regulation of 11β-HSD2 gene expression in human trophoblast tissue.
Non-linear electrooptic effect in antiferroelectric liquid crystal
Authors: Dardas D. , Kuczyński W. , Hoffmann J. , Jeżewski W. , Nowicka K. , Małecki J. 
Published: December 2008

AbstractElectrooptic phenomena caused by weak electric fields, much lower than those needed for the helix unwinding, in helical smectic liquid crystals were studied in thin planar samples. The investigations were performed in chiral liquid crystal 4-(1-methyl-heptyloxycarbonyl) phenyl 4′-(3-butanoyloxy propyl-1-oxy) biphenyl-4-carboxylate which exhibits antiferro-electric properties. We have found that electric field applied to a helical smectic liquid crystal caused two effects. First, the helix was deformed and the position of effective optic axis changed by an angle proportional to the field strength. The second effect, quadratic in field, causes the change in the shape of the indicatrix. As a consequence, the relative changes in the light intensity caused by external electric field consist of two components. The first component represents the modulation with the fundamental frequency and the second one with the doubled frequency (second harmonic of the electrooptic effect). The ab- solute values of the first- and second-order electrooptic coefficients have been determined and their temperature dependence discussed.
Mesomorphic and dielectric properties of esters useful for formulation of nematic mixtures for dual frequency addressing system
Authors: Ziobro D. , Kula P. , Dziaduszek J. , Filipowicz M. , DĄbrowski R. , Parka J. , Czub J. , Urban S. , Wu S.T. 
Published: December 2008

AbstractMesomorphic and dielectric properties of three homologous series of two and three ring fluorosubstituted esters are described. They are 4-cyano-3-fluorophenyl 4-alkyloxy-2-fluorobenzoates, 4-cyano-3-fluorophenyl 4-(4-alkylbenzoyloxy)-2-fluorobenzoates and 3-fluoro-4-cyanophenyl, or 3-fluoro-4-isothiocyanatophenyl or 3,4-difluorophenyl 4′-alkyl-2,3-difluoro-biphenyl-4-carboxylates. The compounds exhibit the nematic mesophase accompanied by the smectic A or smectic C mesophase in some cases. Most of them show strong dependence of the dielectric anisotropy Δε upon frequency, at low frequencies Δε reaches a value ∼200, while at high frequencies a small negative dielectric anisotropy appears.
Preparation and characterization of transparent Nd:YAG ceramics
Authors: Librant Z. , Jabczyński J.K. , Węglarz H. , Wajler A. , Tomaszewski H. , Łukasiewicz T. , Żendzian W. , Kwiatkowski J. 
Published: December 2008

AbstractTransparent Nd:YAG ceramics were produced by solid.state reaction of high.purity (4N) nanometric oxides powders, i.e., Al2O3, Y2O3 and Nd2O3. After sintering, mean grain sizes of 2% Nd:YAG samples were about 20 μm and their transparency were a bit worse than that of 0.9% Nd:YAG single crystal. Two types of active elements: rods and slabs were fabricated and characterized in several diode pumping schemes. In end pumping configuration as a pump source 20.W fiber coupled laser diode operating in low duty cycle regime (1 ms pump duration/20 Hz) was deployed. In the best case, 3.7 W of output power for 18 W of absorbed pump power, M2 < 1.4 were demonstrated for uncoated ceramics Nd:YAG rod of ϕ 4×3mm size in preliminary experiments. For the ceramics of two times lower Nd dopant level above 30% slope efficiency was achieved. In case of Nd:YAG ceramic slab side pumped by 600.W laser diode stack above 12 W was demonstrated with slope efficiency of 3.5%.
Route‐Independent Analysis of Available Capacity in Flexible Manufacturing Systems
Authors: Koltai Tamás , Stecke Kathryn E. 
Published: December 2008

In a job shop, because of large setup times, each operation is assigned to only one machine. There is no alternative routing. In a flexible manufacturing system, each manufacturing operation can often be performed on several machines. Therefore, with automated equipment, the capacity of a machine to perform certain operations is not independent of the capacity of other machines. Often, however, operations managers can use a route‐independent answer to production planning questions. For example, how much can be produced of a certain part type and when are important capacity questions in business negotiations, when the detailed routing and scheduling are not yet of interest or cannot be known. This paper provides a mathematical model for the route‐independent analysis of the capacity of flexible manufacturing systems based on a concept of operation types. An example is provided both to illustrate the use of operation types and to highlight the differences between the traditional route‐dependent and the proposed route‐independent formulations of capacity constraints. Some computational results are also given. Finally, a sensitivity analysis is developed to analyze the feasibility of production plans when production requirements and machine capacities can change.