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951.
Ambrin Fatima M. Fahad Haroon Gerald Wolf Mario Engelmann Mariarosa G. Spina 《Amino acids》2010,38(5):1407-1414
The presence of both Urocortin 1 (Ucn1) and corticotropin-releasing factor 2 receptors (CRF2R) in the hypothalamic supraoptic nucleus (SON) suggests that endogenous Ucn1 released within this brain area acts as a local
signal that might be involved in the regulation of not only endocrine but also behavioural stress responses. To test this
hypothesis, we monitored the effects induced by the administration of a range of doses of synthetic Ucn1 (0.001–1.0 μg) bilaterally
into the SON of rats in the open field test (OFT). Ucn1 administration produced an inverted U-shaped dose–response curve on
OFT behaviour, in particular the dose of 0.01 μg of Ucn1 significantly increased the number of rearing and grooming episodes
without affecting locomotion. In addition, this dosage augmented also the latency to visit the centre of the open field. Pre-treatment
with the CRF2R antagonist, astressin-2B (0.1 μg) normalized Ucn1 treatment-induced effects. These results suggest that Ucn1 released within
the SON area interacts with CRF2R to control the state of arousal. 相似文献
952.
Yi-Chun Loraine Tung Eduard Ayuso Xiaoye Shan Fatima Bosch Stephen O'Rahilly Anthony P. Coll Giles S. H. Yeo 《PloS one》2010,5(1)
Sequence variants in the first intron of FTO are strongly associated with human obesity and human carriers of the risk alleles show evidence for increased appetite and food intake. Mice globally lacking Fto display a complex phenotype characterised by both increased energy expenditure and increased food intake. The site of action of FTO on energy balance is unclear. Fasting reduces levels of Fto mRNA in the arcuate nucleus (ARC) of the hypothalamus, a site where Fto expression is particularly high. In this study, we have extended this nutritional link by demonstrating that consumption of a high fat diet (45%) results in a 2.5 fold increase in Arc Fto expression. We have further explored the role of hypothalamic Fto in the control of food intake by using stereotactic injections coupled with AAV technology to bi-directionally modulate Fto expression. An over expression of Fto protein by 2.5-fold in the ARC results in a 14% decrease in average daily food intake in the first week. In contrast, knocking down Arc Fto expression by 40% increases food intake by 16%. mRNA levels of Agrp, Pomc and Npy, ARC-expressed genes classically associated with the control of food intake, were not affected by the manipulation of Fto expression. However, over expression of Fto resulted in a 4-fold increase in the mRNA levels of Stat3, a signalling molecule critical for leptin receptor signalling, suggesting a possible candidate for the mediation of Fto''s actions. These data provide further support for the notion that FTO itself can influence key components of energy balance, and is therefore a strong candidate for the mediation of the robust association between FTO intronic variants and adiposity. Importantly, this provide the first indication that selective alteration of FTO levels in the hypothalamus can influence food intake, a finding consistent with the reported effects of FTO alleles on appetite and food intake in man. 相似文献
953.
954.
Tewari S Chauhan PM Bhaduri AP Fatima N Chatterjee RK 《Bioorganic & medicinal chemistry letters》2000,10(13):1409-1412
The syntheses of 7-chloro-4-(substituted amino) quinolines (2-22) and their antifilarial activities are delineated. Some of the screened compounds have shown promising filarial response and sterilization effect on female Acanthocheilonema viteae in rodents. 相似文献
955.
Obermeyer G Gehwolf R Sebesta W Hamilton N Gadermaier G Ferreira F Commandeur U Fischer R Bentrup FW 《Methods (San Diego, Calif.)》2004,32(3):235-240
Recombinant allergens have become a valuable tool for diagnosis and may also be used for therapy in the near future. To supply the required large amounts of functional recombinant proteins on a cost-effective basis, the production of allergens in plants by molecular farming is an alternative to microbial expression systems. Especially as post-translational modifications of the allergens, e.g., phosphorylation and glycosylation, may be important for recognition by the human immune system, the plant-based production of recombinant allergens enables the correct folding, glycosylation, and other modifications of the recombinant allergen. An introduction to the methods for plant transformation via the tumor-inducing bacterium, Agrobacterium tumefaciens, is given in this paper. 相似文献
956.
Nussenzveig Daniel R.; Matos Maria De Fatima C.; Thaw Colette N. 《American journal of physiology. Cell physiology》1998,275(5):C1264
The human calcitonin receptor (hCTR) is expressed in polarizedcells of the kidney, bone, and nervous system. In the kidney, hCTRs arefound in cells of the distal nephron to which blood-borne calcitoninhas access only at the basolateral surface. We expressed hCTR subtypes1 and 2 in Madin-Darby canine kidney (MDCK) cells to establish a cellmodel useful for delineating the molecular mechanisms underlying hCTRpolarity. Selective cell surface incubation demonstrated functionalpolarity of hCTRs by equilibrium binding or cross-linking ofradioiodinated salmon calcitonin(125I-sCT) and cAMP accumulationstimulated by sCT. We estimated that at the steady state there are40-fold more hCTRs on the basolateral than on the apical side.Domain-selective cell surface biotinylation followed by immunoblottingof streptavidin-agarose-fractionated biotinylated glycoproteinsindependently confirmed the polarized distribution of FLAGepitope-tagged hCTR-2 in the basolateral domain. Confocal microscopy ofimmunostained receptors revealed that hCTRs are concentrated on alateral subdomain of the basolateral membrane. Cell surface arrivalassay of newly formed receptors demonstrated that direct delivery tothe basolateral domain is the mechanism by which hCTRs becomepolarized. Measurement of receptor turnover on the basolateral surfaceshowed that retention contributes to hCTR distribution at the steadystate. 相似文献
957.
Frederick H. Kasten L. Fatima R. Pineda Paul E. Schneider H. Ralph Rawls Theda A. Foster 《In vitro cellular & developmental biology. Plant》1989,25(1):57-62
Summary Cell culture is a valuable method of evaluating the biocompatibility of new dental materials. The purpose of this study was
to compare the in vitro biocompatibility of an experimental fluoride composite resin with fluoride and non-fluoride-releasing
materials currently available. The dental materials tested were: MQ Silicate (silicate cement), KETAC-CEM and FUJI (type II
glass ionomer cements), VISIO DISPERS (a light-cured, nonfluoridated, microfilled composite resin), and FR-17 (an experimental
fluoride-releasing composite resin). The Smulow-Glickman (S-G) human, gingival epithelial cell line, which exhibits semidifferentiated
characteristics, was used in the study as a test system. Biocompatibility was quantified by counting the viable cells per
unit area remaining after 24 and 48 h at two radial distances from cured specimens immersed in the cell culture medium. The
test materials were observed to be most toxic to cells nearest the materials. A Time-Distance Cytotoxicity Index (TDCI) was
calculated to relate the percentage of dead cells to viable cells at each diffusion distance for each exposure time compared
to a nontoxic control. The relative toxicity ranking of the materials tested based on the TDCI was VISIO DISPERS (91%), FUJI
(82%), FR-17 (30%), MQ Silicate (23%), and KETAC-CEM (10%), which exhibited the least toxicity. The cytotoxicity of the experimental
resin FR-17 was within the range of cytotoxicity of currently accepted restorative materials.
this study was supported in part by grant R01-DE04749 from the National Institutes of Health, Bethesda, MD, to H. R. R., and
by grant no. S07-RR05704-13 from the Biomedical Research Grant Program, Division of Research Resources, National Institutes
of Health, awarded to the Louisiana State University School of Dentistry. 相似文献
958.
David Schlessinger Randy D. Little Diha Freije Fatima Abidi Ileana Zucchi Giovanni Porta Giuseppe Pilia Ramaiah Nagaraja Sandra K. Johnson Jae-Young Yoon Anand Srivastava Juha Kere Giuseppi Palmieri Alfredo Ciccodicola Vittorio Montanaro Giovanna Romano Amelia Casamassimi Michele D'Urso 《Genomics》1991,11(4)
Yeast artificial chromosomes (YACs) have recently provided a potential route to long-range coverage of complex genomes in contiguous cloned DNA. In a pilot project for 50 Mb (1.5% of the human genome), a variety of techniques have been applied to assemble Xq24–q28 YAC contigs up to 8 Mb in length and assess their quality. The results indicate the relative strength of several approaches and support the adequacy of YAC-based methods for mapping the human genome. 相似文献
959.
Fatima Cvrčková 《Applied microbiology and biotechnology》1991,35(4):515-516
Summary A new selection method based on the use of chlorsulfuron (CS) resistance as the selection marker for protoplast fusion in industrial yeast has been introduced using the system of protoplast fusion. A petite mutant of a spontaneously CS-resistant distiller's Saccharomyces cerevisiae strain and a wild-type CS-sensitive strain of the osmotolerant yeast Zygosaccharomyces mellis were fused in order to obtain a distiller's yeast suitable for fermentations on concentrated molasses. Fusion products were isolated as large colonies on minimal glycerol agar with 0.5 mg ml–1 of the herbicide Glean (75% CS). Following prolonged cultivation on molasses, stable hybrid subxlones were obtained.
Offprint requests to: F. Cvrková 相似文献
960.
DHEA, DHEA sulphate and androstenedione are C19 steroïds secreted by the adrenal cortex. These hormones with a weak androgen activity are precursors of estrogens and androgens. In human and other primates these hormones are produced in important quantities, even though, in domestic and laboratory animals, a few secretion is measured. In this survey, the androstenedione is quantified both in plasma and adrenal gland of young, prepubertal and adult rabbits and the castration effects on adrenal cortex histology are noted too. The absolute weight (AW) of the left adrenal gland is slightly higher than the right (p > 0.05) for all animals and the gland absolute weight (AW) for the adult rabbit is superior to the young and prepubertal rabitts (p < 0.05). The castration effect in adult increases the adrenal weight (p < 0.001). A zonation of adrenal cortex for young rabbits is observed. The zona fasciculata is important for young and prepubertal rabbits whereas, the zona reticularis is thicker for the adults. Thickness of glomerulosa, fasciculata and reticularis zonas increased with 6.55% (p > 0.05), 15.9% (p < 0.01) and 79.21% (p < 0.001) for the castred adult rabbits and histological modifications were observed in the zona reticularis. The plasma androstenedione is negligible for the young (0.060 ± 0.01 ng/mL), weak for the prepubertal (0.152 ± 0.03 ng/mL) and reaches (0.263 ± 0.03 ng/mL) for the adult. The androstenedione relative content (ng/100 mg of adrenal weight) is 2.90 ± 0.30; 4.54 ± 0.82 and 1.34 ± 0.36 for the young, prepubertal and adult rabbits. In this work, an increase of the androstenedione adrenal content is observed for the prepubertal rabbits, which could intervene in the process of puberty. 相似文献