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61.
Nikolaos P Polyzos Human M Fatemi Apostolos Zavos Grigoris Grimbizis Dimitra Kyrou Juan-Garcia Velasco Paul Devroey Basil Tarlatzis Evangelos G Papanikolaou 《Reproductive biology and endocrinology : RB&E》2011,9(1):1-5
Background
Serum anti-Mullerian hormone (AMH) is currently considered the best marker of ovarian reserve and of ovarian responsiveness to gonadotropins in in-vitro fertilization (IVF). AMH assay, however, is not available in all IVF Units and is quite expensive, a reason that limits its use in developing countries. The aim of this study is to assess whether the "ovarian sensitivity index" precisely reflects AMH so that this index may be used as a surrogate for AMH in prediction of ovarian response during an IVF cycle.Methods
AMH serum levels were measured in 61 patients undergoing IVF with a "long" stimulation protocol including the GnRH agonist buserelin and recombinant follicle-stimulating hormone (rFSH). Patients were divided into four subgroups according to the percentile of serum AMH and their ovarian stimulation was prospectively followed. Ovarian sensitivity index (OSI) was calculated dividing the total administered FSH dose by the number of retrieved oocytes.Results
AMH and OSI show a highly significant negative correlation (r = -0.67; p = 0.0001) that is stronger than the one between AMH and the total number of retrieved oocytes and than the one between AMH and the total FSH dose.Conclusions
OSI reflects quite satisfactory the AMH level and may be proposed as a surrogate of AMH assay in predicting ovarian responsiveness to FSH in IVF. Being very easy to calculate and costless, its use could be proposed where AMH measurement is not available or in developing countries where limiting costs is of primary importance. 相似文献62.
Gkikas M Iatrou H Thomaidis NS Alexandridis P Hadjichristidis N 《Biomacromolecules》2011,12(6):2396-2406
l-Proline is the only, out of 20 essential, amino acid that contains a cyclized substituted α-amino group (is formally an imino acid), which restricts its conformational shape. The synthesis of well-defined homo- and copolymers of l-proline has been plagued either by the low purity of the monomer or the inability of most initiating species to polymerize the corresponding N-carboxy anhydride (NCA) because they require a hydrogen on the 3-N position of the five-member ring of the NCA, which is missing. Herein, highly pure l-proline NCA was synthesized by using the Boc-protected, rather than the free amino acid. The protection of the amine group as well as the efficient purification method utilized resulted in the synthesis of highly pure l-proline NCA. The high purity of the monomer and the use of an amino initiator, which does not require the presence of the 3-N hydrogen, led for the first time to well-defined poly(l-proline) (PLP) homopolymers, poly(ethylene oxide)-b-poly(l-proline), and poly(l-proline)-b-poly(ethylene oxide)-b-poly(l-proline) hybrids, along with poly(γ-benzyl-l-glutamate)-b-poly(l-proline) and poly(Boc-l-lysine)-b-poly(l-proline) copolypeptides. The combined characterization (NMR, FTIR, and MS) that results for the l-proline NCA revealed its high purity. In addition, all synthesized polymers exhibit high molecular and compositional homogeneity. 相似文献
63.
Spagou K Theodoridis G Wilson I Raikos N Greaves P Edwards R Nolan B Klapa MI 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(17-18):1467-1475
Metabolic profiling of biofluids, based on the quantitative analysis of the concentration profile of their free low molecular mass metabolites, has been playing increasing role employed as a means to gain understanding of the progression of metabolic disorders, including obesity. Chromatographic methods coupled with mass spectrometry have been established as a strategy for metabolic profiling. Among these, GC-MS, targeting mainly the primary metabolism intermediates, offers high sensitivity, good peak resolution and extensive databases. However, the derivatization step required for many involatile metabolites necessitates specific data validation, normalization and analysis protocols to ensure accurate and reproducible performance. In this study, the GC-MS metabolic profiles of plasma samples from mice maintained on 12- or 15-month long low (10 kcal%) or high (60 kcal%) fat diets were obtained. The profiles of the trimethylsilyl(TMS)-methoxime(MeOx) derivatives of the free polar metabolites were acquired through GC-(ion trap)MS, using [U-(13)C]-glucose as the internal standard. After the application of a recently developed data correction and normalization/filtering protocol for GC-MS metabolomic datasets, the profiles of 48 out of the 77 detected metabolites were used in multivariate statistical analysis. Data mining suggested a decrease in the activity of the energy metabolism with age. In addition, the metabolic profiles indicated the presence of subpopulations with different physiology within the high- and low-fat diet mice, which correlated well with the difference in body weight among the animals and current knowledge about hyperglycemic conditions. 相似文献
64.
65.
Nikolaos A. Skondras Christos A. Karavitis Ippokratis I. Gkotsis P.J.B. Scott Ursula L. Kaly Stavros G. Alexandris 《Ecological Indicators》2011,11(6):1699-1706
The Environmental Vulnerability Index (EVI) was developed by the Pacific Islands Applied Geoscience Commission as a global composite index that quantifies the vulnerability of an area's environment. Greece has been selected as reference area due to its current physical and anthropogenic conditions that may lead to environmental instabilities in the natural, social, and economic infrastructure environment. Hence, in the present approach, using data on Greece, an effort to define the range of information that the EVI may provide for the pertinent country is presented and a discussion on whether the index may be further developed is conveyed. Advantages as well as shortcomings of the Index are also delineated. 相似文献
66.
Maastrichtian Foraminifera from the sedimentary beds at Ain Mdeker are recorded and identified. The fauna examined is found to be clearly Tethyan in composition. On the basis of this fauna, four planktic foraminiferal zones, the Globotruncana falsostuarti Zone, the Rugotruncana gansseri Zone, the Abathomphalus mayaroensis Zone and the Globotruncana falsocalcarata Zone are distinguished in the Maastrichtian of the sequence studied. These zones are futher compared with the zones established in equivalent strata in the sequence at El Kef, the most complete sequence in Tunisia. In addition to the index species only the biostratigraphically most important species from the fauna studied are illustrated. 相似文献
67.
Malamitsi-Puchner A Economou E Boutsikou T Nikolaou KE Vrachnis N 《Mediators of inflammation》2005,2005(1):53-56
Our aim is to determine--in 30 healthy full-term infants and their mothers--circulating levels of neurotrophin-3 (NT-3) (important for antenatal and postnatal brain development and implicated in the immune response) and FLT3 tyrosine kinase receptor (FLT3) (controlling hematopoiesis and found in the nervous tissue), in the fetal and neonatal life. NT-3 levels, in contrast to FLT3 ones, increased significantly on the fourth postnatal day in relation to the low levels found in the mother, fetus, and day 1 neonate (P = .03, respectively). Maternal and umbilical NT3 levels positively correlated with respective FLT3 levels (P = .003 and P = .03). Circulating NT-3 levels increased in early neonatal life, possibly due to exposure to various stimuli soon after birth. FLT3 levels do not seem to behave accordingly, although these two substances probably synergize. 相似文献
68.
Luminita A Stanciu Kevan Roberts Nikolaos G Papadopoulos Sang-Heon Cho Stephen T Holgate Anthony J Coyle Sebastian L Johnston 《Respiratory research》2005,6(1):67
Background
Virus infections are the major cause of asthma exacerbations. CD8+ T cells have an important role in antiviral immune responses and animal studies suggest a role for CD8+ T cells in the pathogenesis of virus-induced asthma exacerbations. We have previously shown that the presence of IL-4 during stimulation increases the frequency of IL-5-positive cells and CD30 surface staining in CD8+ T cells from healthy, normal subjects. In this study, we investigated whether excess IL-4 during repeated TCR/CD3 stimulation of CD8+ T cells from atopic asthmatic subjects alters the balance of type 1/type 2 cytokine production in favour of the latter.Methods
Peripheral blood CD8+ T cells from mild atopic asthmatic subjects were stimulated in vitro with anti-CD3 and IL-2 ± excess IL-4 and the expression of activation and adhesion molecules and type 1 and type 2 cytokine production were assessed.Results
Surface expression of very late antigen-4 [VLA-4] and LFA-1 was decreased and the production of the type 2 cytokines IL-5 and IL-13 was augmented by the presence of IL-4 during stimulation of CD8+ T cells from mild atopic asthmatics.Conclusion
These data suggest that during a respiratory virus infection activated CD8+ T cells from asthmatic subjects may produce excess type 2 cytokines and may contribute to asthma exacerbation by augmenting allergic inflammation. 相似文献69.
Glutathione S-transferases (GSTs, EC 2.5.1.18) are a multigene family of detoxification enzymes that biotransform a wide variety of endogenous and exogenous electrophilic substrates, including herbicides. The isozyme GST I from maize exhibits significant catalytic activity for the chloroacetanilide herbicide alachlor and appears to be involved in its detoxifying process. To establish the in planta ability of GST I to detoxify from alachlor, transgenesis studies were carried out. The gene gstI-6His, which encodes for 6His-tagged GST I, was used for the construction of a binary vector suitable for genetic engineering of tobacco plants (Nicotiana tabacum). Through biolistic method transgenic tobacco plants were obtained. Integration of gstI-6His gene in transgenic tobacco plants genome was confirmed by polymerase chain reaction and Southern blot hybridization. The expression of active GST I was established by Western blot analysis, using anti-6His antibody, and by direct purification of 6-His tagged GST I on Ni-NTA agarose. Primary transformed plants harboring the gstI-6His gene were transferred to MS medium supplemented with alachlor and their phenotype was evaluated. The transgenic plants showed substantially higher tolerance to alachlor compared to non-transgenic plants in terms of root, leaves and vigorous development. These transgenic plants are potentially useful biotechnological tools for the development of phytoremediation system for the degradation of herbicide pollutants in agricultural fields. 相似文献
70.
Apostolos Bossios Stelios Psarras Dimitrios Gourgiotis Chrysanthi L Skevaki Andreas G Constantopoulos Photini Saxoni-Papageorgiou Nikolaos G Papadopoulos 《Respiratory research》2005,6(1):114