34 research outputs found

    Hormonal parameters and embryological outcomes of in vitro fertilisation/intra cytoplasmic sperm injection cycles in women using dydrogesterone for the prevention of premature luteinizing hormone surge during ovarian stimulation

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    Aim. To evaluate the hormonal parameters and embryological outcomes of an ovarian stimulation protocol using dydrogesterone to prevent the premature LH surge in IVF/ICSI programmes. Materials and methods. A prospective study randomised, including 79 women with normal ovarian reserve undergoing ovarian stimulation for IVF/ICSI with recombinant FSH (rFSH) from Day 2 or 3 of the menstrual cycle. To prevent the premature LH surge, participants in Group 1 (n=38) received oral dydrogesterone 20 mg/day from the start of ovarian stimulation until the day of ovulation trigger administration. Participants in Group 2 (n=41) received a GnRH antagonist. We evaluated the starting and total dose of gonadotropins, duration of stimulation, serum levels of LH, oestradiol and progesterone on Day 1 and 6 of stimulation and the day of trigger administration, number of retrieved and mature oocytes, fertilization rate, and the number of blastocysts and cryopreserved embryos. Results. There were no significant differences in most hormonal parameters, characteristics of the ovarian stimulation and embryological outcomes between the two groups. Serum levels of progesterone in the dydrogesterone arm were higher than in the GnRH antagonist arm (2.3 nmol/l [2.03.4] vs 1.5 [1.02.4] nmol/l; p=0.026), but without any impact on the embryological outcomes. Conclusion. Prevention of premature LH surge in ovarian stimulation cycles using oral dydrogesterone may represent a convenient alternative to the conventional use of GnRH antagonists, reducing the number of required injections and potentially increasing the convenience in patients who are not planning a fresh embryo transfer

    Signatures of Molecular Unification and Progressive Oxidation Unfold in Dissolved Organic Matter of the Ob-Irtysh River System along Its Path to the Arctic Ocean

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    The Ob-Irtysh River system is the seventh-longest one in the world. Unlike the other Great Siberian rivers, it is only slightly impacted by the continuous permafrost in its low flow. Instead, it drains the Great Vasyugan mire, which is the world largest swamp, and receives huge load of the Irtysh waters which drain the populated lowlands of the East Siberian Plain. The central challenge of this paper is to understand the processes responsible for molecular transformations of natural organic matter (NOM) in the Ob-Irtysh river system along the South-North transect. For solving this task, the NOM was isolated from the water samples collected along the 3,000?km transect using solid-phase extraction. The NOM samples were further analyzed using high resolution mass spectrometry and optical spectroscopy. The obtained results have shown a distinct trend both in molecular composition and diversity of the NOM along the South-North transect: the largest diversity was observed in the Southern “swamp-wetland” stations. The samples were dominated with humic and lignin-like components, and enriched with aminosugars. After the Irtysh confluence, the molecular nature of NOM has changed drastically: it became much more oxidized and enriched with heterocyclic N-containing compounds. These molecular features are very different from the aliphatics-rich permafrost NOM. They witnesses much more conservative nature of the NOM discharged into the Arctic by the Ob-Irtysh river system. In general, drastic reduction in molecular diversity was observed in the northern stations located in the lower Ob flow

    Interactions between Humic Substances and Microorganisms and Their Implications for Nature-like Bioremediation Technologies

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    The state of the art of the reported data on interactions between microorganisms and HSs is presented herein. The properties of HSs are discussed in terms of microbial utilization, degradation, and transformation. The data on biologically active individual compounds found in HSs are summarized. Bacteria of the phylum Proteobacteria and fungi of the phyla Basidiomycota and Ascomycota were found to be the main HS degraders, while Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes were found to be the predominant phyla in humic-reducing microorganisms (HRMs). Some promising aspects of interactions between microorganisms and HSs are discussed as a feasible basis for nature-like biotechnologies, including the production of enzymes capable of catalyzing the oxidative binding of organic pollutants to HSs, while electron shuttling through the utilization of HSs by HRMs as electron shuttles may be used for the enhancement of organic pollutant biodegradation or lowering bioavailability of some metals. Utilization of HSs by HRMs as terminal electron acceptors may suppress electron transfer to CO2, reducing the formation of CH4 in temporarily anoxic systems. The data reported so far are mostly related to the use of HSs as redox compounds. HSs are capable of altering the composition of the microbial community, and there are environmental conditions that determine the efficiency of HSs. To facilitate the development of HS-based technologies, complex studies addressing these factors are in demand

    Interaction of Antibiotics and Humic Substances: Environmental Consequences and Remediation Prospects

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    The occurrence and distribution of antibiotics in the environment has received increasing attention due to their potential adverse effects on human health and ecosystems. Humic substances (HS) influence the mobility, reactivity, and bioavailability of antibiotics in the environment significantly due to their interaction. As a result, HS can affect the dissemination of antibiotic-resistance genes, which is one of the main problems arising from contamination with antibiotics. The review provides quantitative data on the binding of HS with fluoroquinolones, macrolides, sulfonamides, and tetracyclines and reports the proposed mechanisms of their interaction. The main issues of the quantification of antibiotic–HS interaction are discussed, which are a development of standard approaches and the accumulation of a dataset using a standard methodology. This would allow the implementation of a meta-analysis of data to reveal the patterns of the binding of antibiotics to HS. Examples of successful development of humic-based sorbents for fluoroquinolone and tetracycline removal from environmental water systems or polluted wastewaters were given. Data on the various effects of HS on the dissemination of antibiotic-resistance genes (ARGs) were summarized. The detailed characterization of HS properties as a key point of assessing the environmental consequences of the formation of antibiotic–HS complexes, such as the dissemination of antibiotic resistance, was proposed

    Natural complex mixtures unequivocally defined in formulae difference space

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    Direct comparison of high-resolution mass spectrometry (HRMS) data acquired with different instrumentation or parameters remains difficult as the derived lists of molecular species via HRMS, even for the same sample, appear distinct. This inconsistency is the result of inherent inaccuracies caused by instrumental limitations and sample conditions. We propose a method that classifies HRMS data based on the differences in the number of elements between each pair of molecular formulae within the formulae list to preserve the essence of the given sample. The novel metric, Formulae Difference Chains Expected Length (FDCEL), allowed for comparing and classifying samples measured by different instruments. FDCEL metric was implemented for both spectrum quality control and for examination of samples of various nature. We also demonstrate a web application and a prototype for a uniform database for HRMS data serving as a benchmark for future biogeochemical applications

    Humic substances and nature-like technologies: Learning from nature: understanding humic substances structures and interactions for the development of environmentally friendly, nature-like technologies

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    2 páginas.- 11 referencias.- Open Access in Versión de editor https://doi.org/10.1007/s11368-019-02330-6Humic substances (HS) are viewed as an inherent component of soil organic matter, which plays multiple life-sustaining functions in the environment. The complexity of the molecular ensemble of humic substances is reflected in singular physicochemical features and results in uniquely broad and diverse interactions with both abiotic components and living organisms directed towards adaptation of life to its abiotic environment. The reported examples of mediating roles of HS in soil range from the transport of available nutrients in soil solution (Olaetxea et al. 2018) to the remediation of contaminated soils (Perminova and Hatfield 2005). Still, the major problem remains in transferring the molecular engineering of nature into the technology world. This problem gave rise to the topic of the Fourth International Conference on Humic Innovative Technologies (HIT) BFrom molecular analysis of humic substances - to nature-like technologies,^ which was organized by the CIS chapter of the International Humic Substances Society on October 15–20, 2017, in Moscow, Russia (www.humus.ru/hit-2017). The papers presented at that conference formed the basis for this special issue of the Journal of Soils and Sediments.Peer reviewe
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