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141.
BIM 23014 is a somatostatin analog displaying an increased biological half life due to resistance to enzymatic degradation. This peptide inhibits GH release directly at the level of pituitary somatotrophs. In addition, an action of BIM 23014 at the level of the hypothalamus is possible since somatostatinergic fibers and receptors have been identified on GH-RH neurons. To evaluate the effect of BIM 23014 on GH-RH secretion, hypophysial portal blood (HPB) was continuously collected in conscious sheep. Twelve rams (40-45 kg, 9-month-old) with chronically implanted perihypophysial cannulae were i.v. injected with BIM 23014 (1 mg) or saline. HPB and jugular blood were collected for 3-5 hours before and after the injection for the determinations of GH-RH and GH concentrations respectively. The acute injection of BIM 23014 induced a rapid decrease of plasma GH within the first two hours. Simultaneously, GH-RH in HPB decreased significantly. After reaching a nadir, GH concentrations increased to values greater than baseline. A similar rebound in GH-RH levels in HPB was also observed. These data indicate that BIM 23014 acts at the level of GH-RH hypothalamic neurons, in addition to its well-know effect on the pituitary gland.  相似文献   
142.
The pag gene coding for protective antigen (PA), one of the three toxin components of Bacillus anthracis, has been cloned into the mobilizable shuttle vector pAT187 and transferred by conjugation from Escherichia coli to B. anthracis. Using this strategy, an insertionally mutated pag gene constructed and characterized in E. coli, was introduced into B. anthracis Sterne strain. This transconjugant was used to select a recombinant clone (RP8) carrying the inactivated pag gene on the toxin-encoding plasmid, pXO1. Strain RP8 was deficient for PA while still producing the two other toxin components, i.e. lethal factor (LF) and edema factor (EF). In contrast to spores from the wild-type Sterne strain, spores prepared from RP8 were totally non-lethal in mice. These results clearly establish the central role played by PA in B. anthracis pathogenicity.  相似文献   
143.
A multiparametric analysis of the effects of human recombinant interferon alpha type A on Daudi cells involving flow cytometry and in vitro analysis of alpha and beta DNA polymerase activities has been performed. Results have disclosed (within 60 min of interferon treatment) a decrease of alpha polymerase driven DNA synthesis persisting to at least 24 h, while beta polymerase was poorly affected. Moreover, after 24 h of interferon treatment, a reduction of BrdUrd incorporation per cell, assessed by flow cytometry, was observed suggesting that DNA synthesis in S phase cells is almost completely abolished. The analysis of the effect of interferon on the distribution of cell cycle phases indicated that the G1/S transition is not inhibited by the treatment. These results support the hypothesis that interferon generates a transient initiating signal which quickly reaches the nucleus and produces a rapid inhibition of alpha polymerase activity, leading finally to the slowing of cell cycle progression.  相似文献   
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Olive oil mill wastewater (OMWW) was used as a substrate for the culture of a mixture of edible fungi in order to obtain a potentially useful microbial biomass and to induce a partial bioremediation of this fastidious waste. Before fermentation, the OMWW underwent an alkaline-oxidative treatment with the aim of decreasing the polyphenolic content which is the main cause of its toxicity. The fungal mixture grew fairly well in the treated OMWW and reached a maximum of biomass production within about 14 days of fermentation at room temperature. Up to 150–160 g of wet biomass was obtained per liter of OMWW. Analysis of the partially dehydrated biomass revealed a protein content of about 13 g% and 6 g% of row fiber. A relevant presence of unsaturated fatty acids was found, as well as the presence of significant amounts of vitamins A and E, nicotinic acid, calcium, potassium and iron. The possibility of using the microbial biomass produced from OMWW as an additive to animal feed is discussed.  相似文献   
146.

Introduction

Endometriosis is an estrogen-dependent gynecological disease that causes infertility, and potential metabolomic biomarkers related to ovarian endometriosis and poor outcomes after assisted reproductive treatments are still lacking.

Objectives

The present study analyzed the metabolomic profiling of follicular fluid samples from 40 patients undergoing in vitro fertilization.

Methods

The follicular fluid samples were classified as controls (n = 22) and endometriosis patients (n = 18). The samples were submitted to Bligh and Dyer protocol followed by metabolomics analysis by ultra-performance liquid chromatography mass spectrometry. Clinical data was assessed by Students’ T-test and metabolomics data was analyzed by multivariate statistics by MetaboAnalyst 3.0 to obtain intrinsic characteristics that allowed for groups discrimination. The Receiver Operating Characteristic curve was carried out for the proposed biomarkers, aiming to determine their specificity and sensitivity, as a set and individually.

Results

From the metabolomic analysis, 20 ion masses were selected as potential biomarkers from principal component analysis, which showed that all biomarkers were more abundant in the endometriosis group when compared to controls. Tentative attribution was performed by lipid maps database, demonstrating that these potential biomarkers correspond to fatty acids, carnitines, monoacylglycerols, lysophosphatidic acids, lysophosphatidylglycerols, diacylglycerols, lysophosphatidylcholines, phosphatidylserine, lysophosphatidylinositols and Phosphatidic Acid.

Conclusion

The use of mass spectrometry-based metabolomics allowed for the identification of effective biomarkers for ovarian endometriosis, which may contribute for a better comprehension of the disease and how it affects the ovary, as well as assisting in the development of accessory tools for endometriosis diagnosis and infertility management.
  相似文献   
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148.
The new benthic toxic dinoflagellate, Ostreopsis fattorussoi sp. nov., is described from the Eastern Mediterranean Sea, Lebanon and Cyprus coasts, and is supported by morphological and molecular data. The plate formula, Po, 3′, 7″, 6c, 7s, 5?, 2′′′′, is typical for the Ostreopsis genus. It differs from all other Ostreopsis species in that (i) the curved suture between plates 1′ and 3′ makes them approximately hexagonal, (ii) the 1′ plate lies in the left half of the epitheca and is obliquely orientated leading to a characteristic shape of plate 6″. The round thecal pores are bigger than the other two Mediterranean species (O. cf. ovata and O. cf. siamensis). O. fattorussoi is among the smallest species of the genus (DV: 60.07 ± 5.63 μm, AP: 25.66 ± 2.97 μm, W: 39.81 ± 5.05 μm) along with O. ovata. Phylogenetic analyses based on the LSU and internal transcribed spacer rDNA shows that O. fattorussoi belongs to the Atlantic/Mediterranean Ostreopsis spp. clade separated from the other Ostreopsis species. Ostreopsis fattorussoi produces OVTX‐a and structural isomers OVTX‐d and ‐e, O. cf. ovata is the only other species of this genus known to produce these toxins. The Lebanese O. fattorussoi did not produce the new palytoxin‐like compounds (ovatoxin‐i, ovatoxin‐j1, ovatoxin‐j2, and ovatoxin‐k) that were previously found in O. fattorussoi from Cyprus. The toxin content was in the range of 0.28–0.94 pg · cell?1. On the Lebanon coast, O. fattorussoi was recorded throughout the year 2015 (temperature range 18°C–31.5°C), with peaks in June and August.  相似文献   
149.
Synopsis Fifteen days oldOreochromis niloticus andO. mossambicus juveniles were gradually adapted to 10, 20, 30 and 35 ppt sea water. Kidney morphology was observed after transfer to higher salinities and compared with freshwater controls. Despite differences in salinity tolerance, both species have similar transformations when transferred at high salinity, particularly reduction of the glomerular area after 2 months adaptation to sea water, and change in tubule morphology.  相似文献   
150.
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