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The efficacy and safety of a 12-month treatment with recombinant human growth hormone from mammalian cells (r-hGH, Saizen) in growth hormone neurosecretory dysfunction (GHND) are evaluated in this study. r-hGH was administered subcutaneously, at a dosage of 0.5 IU/kg/week divided into 6 equal daily doses. A total of 16 (12 M and 4 F) poorly growing patients, height -2.3 SD or more below the mean for chronological age and sex, were included in the study. r-hGH therapy significantly increased the growth velocity; from 3.57 +/- 0.85 cm/year, before therapy, to 7.09 +/- 2.29 cm/year after 12 months (p less than 0.001). Patients' height SD score rose from -3.40 +/- 0.84 SDS to -2.98 +/- 0.69 SDS (p less than 0.01). Somatomedin C increased significantly from a baseline value of 0.59 +/- 0.32 U/ml to 1.26 +/- 0.66 U/ml after therapy (p less than 0.01). Finally, r-hGH therapy improved the pretreatment adult height prediction; from an initial prognosis of -2.66 +/- 0.79 SDS to -2.17 +/- 0.81 SDS after treatment (p less than 0.01). No side effects or adverse reactions were observed during treatment. Anti-r-hGH antibody formation was not found in any of the patients included in the study. 相似文献
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The effects of subcutaneous (s.c.), intrathecal (i.t.) and intracerebroventricular (i.c.v.) injection of fentanyl and D-Ala2,D-Leu5-enkephalin (DADLE) on intestinal myoelectrical activity were examined in fed rats. In rats with chronically implanted electrodes on the small and large bowel, i.c.v. fentanyl and DADLE restored the 'fasted' pattern of duodenal activity, i.e. the migrating myoelectric complex (MMC) for 8-12 h at a dose as small as 1 nM/kg. In addition, the colonic pattern of activity evaluated as the number of migrating spike bursts (MSB) per min was nearly halved for 1 h following i.c.v. fentanyl (10 nM/kg). Pretreatment with naloxone, but not methylnaloxone prevented these effects on the small and large bowel. Fentanyl (100 nM/kg s.c.) significantly reduced small and large bowel motility, but DADLE (100 nM/kg s.c.) which induced a transient 'fasted pattern' on the duodenum strongly stimulated colonic motor activity. Pretreatment with methylnaloxone prevented the inhibitory effects of s.c. fentanyl but not the colonic excitatory effects of DADLE. The i.t. administration of fentanyl and DADLE did not modify the activity pattern of the bowel. Again, i.t. DADLE stimulated the colon, even after methylnaloxone treatment and at doses 100 times less than the smallest active s.c. dose. The long-lasting changes in small bowel motility and the important delay following DADLE and fentanyl i.c.v., reinforces the hypothesis of a central opioid control of the gastrointestinal motor pattern with possible involvement of released substances.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Maria Lázaro-Berenguer Francisco Paredes-Martínez Yolanda Bel Rafael Núñez-Ramírez Ernesto Arias-Palomo Patricia Casino Juan Ferré 《Microbial biotechnology》2022,15(10):2607-2618
Vip3 proteins are produced by Bacillus thuringiensis and are toxic against lepidopterans, reason why the vip3Aa gene has been introduced into cotton and corn to control agricultural pests. Recently, the structure of Vip3 proteins has been determined and consists of a tetramer where each monomer is composed of five structural domains. The transition from protoxin to the trypsin-activated form involves a major conformational change of the N-terminal Domain I, which is remodelled into a tetrameric coiled-coil structure that is thought to insert into the apical membrane of the midgut cells. To better understand the relevance of this major change in Domain I for the insecticidal activity, we have generated several mutants aimed to alter the activity and remodelling capacity of this central region to understand its function. These mutants have been characterized by proteolytic processing, negative staining electron microscopy, and toxicity bioassays against Spodoptera exigua. The results show the crucial role of helix α1 for the insecticidal activity and in restraining the Domain I in the protoxin conformation, the importance of the remodelling of helices α2 and α3, the proteolytic processing that takes place between Domains I and II, and the role of the C-t Domains IV and V to sustain the conformational change necessary for toxicity. 相似文献
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Amelia Tan Suet May Suaberon Ferr Angelus C. Vad Johanne Fahmi Afiq Durrani Mohd Saludes Jonel P. Bhubalan Kesaven 《Marine biotechnology (New York, N.Y.)》2022,24(3):492-512
Marine Biotechnology - Many industrially significant compounds have been derived from natural products in the environment. Research efforts so far have contributed to the discovery of beneficial... 相似文献
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Marraccini P Vinecky F Alves GS Ramos HJ Elbelt S Vieira NG Carneiro FA Sujii PS Alekcevetch JC Silva VA DaMatta FM Ferrão MA Leroy T Pot D Vieira LG da Silva FR Andrade AC 《Journal of experimental botany》2012,63(11):4191-4212
The aim of this study was to investigate the molecular mechanisms underlying drought acclimation in coffee plants by the identification of candidate genes (CGs) using different approaches. The first approach used the data generated during the Brazilian Coffee expressed sequence tag (EST) project to select 13 CGs by an in silico analysis (electronic northern). The second approach was based on screening macroarrays spotted with plasmid DNA (coffee ESTs) with separate hybridizations using leaf cDNA probes from drought-tolerant and susceptible clones of Coffea canephora var. Conilon, grown under different water regimes. This allowed the isolation of seven additional CGs. The third approach used two-dimensional gel electrophoresis to identify proteins displaying differential accumulation in leaves of drought-tolerant and susceptible clones of C. canephora. Six of them were characterized by MALDI-TOF-MS/MS (matrix-assisted laser desorption-time of flight-tandem mass spectrometry) and the corresponding proteins were identified. Finally, additional CGs were selected from the literature, and quantitative real-time polymerase chain reaction (qPCR) was performed to analyse the expression of all identified CGs. Altogether, >40 genes presenting differential gene expression during drought acclimation were identified, some of them showing different expression profiles between drought-tolerant and susceptible clones. Based on the obtained results, it can be concluded that factors involved a complex network of responses probably involving the abscisic signalling pathway and nitric oxide are major molecular determinants that might explain the better efficiency in controlling stomata closure and transpiration displayed by drought-tolerant clones of C. canephora. 相似文献
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The C-function, according to the ABC model of floral organ identity, is required for stamen and carpel development and to provide floral meristem determinacy. Members of the AG lineage of the large MADS box gene family specify the C-function in a broadly conserved manner in angiosperms. In core eudicots, two sub-lineages co-exist, euAG and PLE, which have been extensively characterized in Antirrhinum majus and Arabidopsis thaliana, where strong sub-functionalization has led to highly divergent contributions of the respective paralogs to the C-function. Various scenarios have been proposed to reconstruct the evolutionary history of the euAG and PLE lineages in eudicots, but detailed functional analyses of the roles of these genes in additional representative species to validate evolutionary hypotheses are scarce. Here, we report functional characterization of euAG- and PLE-like genes in Nicotiana benthamiana through expression analyses and phenotypic characterization of the defects caused by their specific down-regulation. We show that both paralogs redundantly contribute to the C-function in this species, providing insights on the likely evolution of these gene lineages following divergence of the major groups within the eudicots (rosids and asterids). Moreover, we have demonstrated a conserved role for the PLE-like genes in controlling fruit dehiscence, which strongly supports the ancestral role of PLE-like genes in late fruit development and suggests a common evolutionary origin of late developmental processes in dry (dehiscent) and fleshy (ripening) fruits. 相似文献