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Khan AS Fiorotto ML Cummings KK Pope MA Brown PA Draghia-Akli R 《American journal of physiology. Endocrinology and metabolism》2003,285(1):E224-E231
Previous studies from our laboratory have demonstrated that administration of a myogenic plasmid that encodes a protease-resistant growth hormone-releasing hormone (HV-GHRH) to pregnant rat dams augmented long-term growth in first-generation progeny. In the present study, gilts were injected intra-muscularly at day 85 of gestation with 0, 0.1, 0.5, 1, or 5 mg of the HV-GHRH-expressing plasmid and were then electroporated. Piglets were weighed and bled periodically from birth to 100 kg. Piglets from gilts treated with 1 and 5 mg of HV-GHRH plasmid were larger at birth and weaning compared with controls. These two groups reached 100 kg 9 days earlier than the other groups. GHRH levels were increased at birth in piglets from treated gilts. IGF-I levels were significantly increased in the 5-mg group beginning at 21 days of age compared with controls. Pituitaries from the 5-mg group contained a significantly increased number of somatotrophs and lactotrophs from birth to 100 kg. This study confirms that enhanced maternal GHRH production results in intergenerational growth augmentation and that the magnitude of the response is dose dependent. The similarity of the response across species suggests that the effect is likely exerted as a fundamental component of gestational and developmental physiology. 相似文献
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del Campo R Criado JJ Gheorghe R González FJ Hermosa MR Sanz F Manzano JL Monte E Rodríguez-Fernández E 《Journal of inorganic biochemistry》2004,98(8):1307-1314
The thiourea derivatives of N-butylmethylamine (3-benzoyl-1-butyl-1-methyl-thiourea) (1), N-ethylisopropylamine (3-benzoyl-1-ethyl-1-isopropyl-thiourea) (2) and the corresponding complexes of 1 and 2 with Ni(II), Co(III) and Pt(II) have been synthesized. The compounds obtained were characterized by elemental analysis, spectroscopic methods (FT-IR, UV-Vis and NMR) and mass spectrometry. Compound 1, crystallized in the triclinic space group. The antifungal activities of compounds 1 and 2 and their corresponding complexes against the fungus Penicillium digitatum and against the yeast Saccharomyces cerevisiae were investigated. In general, fungal growth inhibition was higher with compound 1 and its complexes than with compound 2, except for the Co(III) complex of 2. 相似文献
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Diaconu CC Bleotu C Chivu M Alexiu I Petrusca D Anton G Achim R Ruta SM Cernescu C 《Journal of cellular and molecular medicine》2004,8(1):93-101
There are few information concerning the changes associated with the transition interval when slow growing, primary explanted human cancer cells are displaced by new selected faster growing cells and became an immortal cell line. In a previous paper ( J. Cell. Mol. Med. , 5 : 49–59, 2001) we described the TV cell line derived from a laryngeal tumor which harbors human papillomavirus (HPV) gene sequences throughout more than sixty in vitro passages. In this paper we analyze the modifications observed during the crisis interval when significant amount of cells senesce but occasional cells acquire some mutations that make them immortal. Confocal microscopy analysis revealed the heterogeneity of the cells in terms of their size and nucleus/cell ratio. Proliferation capacity was assessed by flow cytometry analyzing DNA content and expression of transferrin receptor (CD71). We discussed the possibility that HPV genome sequences alleviate a proliferation block during the crisis growth arrest of human larynx carcinoma cell line and the possibility that the cells monitor their size and growth by measuring the levels of some protein whose synthesis is coupled to cell development. 相似文献
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Quantitative analysis reveals dominance of gliogenesis over neurogenesis in an adult brainstem oscillator
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Ruxandra F. Sîrbulescu Iulian Ilieş Günther K.H. Zupanc 《Developmental neurobiology》2014,74(9):934-952
Neural stem/progenitor cells in the neurogenic niches of the adult brain are widely assumed to give rise predominantly to neurons, rather than glia. Here, we performed a quantitative analysis of the resident neural progenitors and their progeny in the adult pacemaker nucleus (Pn) of the weakly electric fish Apteronotus leptorhynchus. Approximately 15% of all cells in this brainstem nucleus are radial glia‐like neural stem/progenitor cells. They are distributed uniformly within the tissue and are characterized by the expression of Sox2 and Meis 1/2/3. Approximately 2–3% of them are mitotically active, as indicated by expression of proliferating cell nuclear antigen. Labeling of proliferating cells with a single pulse of BrdU, followed by chases of up to 100 days, revealed that new cells are generated uniformly throughout the nucleus and do not undergo substantial migration. New cells differentiate into S100+ astrocytes and Hu C/D+ small interneurons at a ratio of 4:1, reflecting the proportions of the total glia and neurons in this brain region. The continuous addition of new cells leads to a diffuse growth of the Pn, which doubles in volume and total cell number over the first 2 years following sexual maturation of the fish. However, the number of pacemaker and relay cells, which constitute the oscillatory neural network, remains constant throughout adult life. We hypothesize that the dominance of gliogenesis is an adaptation to the high‐frequency firing of the oscillatory neurons in this nucleus. © 2014 Wiley Periodicals, Inc. Develop Neurobiol 74: 934–952, 2014 相似文献
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Patricia A Brown Angela M Bodles-Brakhop Melissa A Pope Ruxandra Draghia-Akli 《BMC biotechnology》2009,9(1):4
Background
Growth hormone-releasing hormone (GHRH) plasmid-based therapy for the treatment of chronic renal failure and its complications was examined. Companion dogs (13.1 ± 0.8 years, 29.4 ± 5.01 kg) and cats (13.2 ± 0.9 years, 8.5 ± 0.37 kg) received a single 0.4 mg or 0.1 mg species-specific plasmid injection, respectively, intramuscularly followed by electroporation, and analyzed up to 75 days post-treatment; controls underwent electroporation without plasmid administration. 相似文献78.
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