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1.
Z Geburtshilfe Neonatol ; 227(5): 390-397, 2023 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-37130551

RESUMEN

Adnexal masses affect 2-10% of all pregnancies. The highest incidence of 1-6% can be seen in the first trimester, with a high rate of spontaneous remission. Two percent of these masses are malignant neoplasms or borderline tumors. A rare benign mass of the adnexa in pregnancy is hyperreactio luteinalis characterised by bilateral, multicystic ovaries with a frequent occurrence in the 3rd trimester. Clinical signs include maternal hyperandrogenaemia with virilisation, hyperemesis, nonspecific abdominal pain or laboratory findings of hyperthyroidism and elevated ß-HCG. Hyperreactio luteinalis does not require therapy due to complete spontaneous remission postpartum, but is often treated surgically in graviditate. In our case we report a first-time gravida in the 31st week of pregnancy with a symptomatic 25-cm multicystic, partly solid mass. After antenatal corticosteroid therapy, an exploratory laparotomy with right adnexectomy was performed on suspicion of malignancy. Histology revealed a hyperreactio luteinalis with an incidental finding of a serous borderline tumor of the ovary (FIGO IIIB). At 33 weeks of gestation, a pathological CTG was observed, and an urgent secondary caesarean section by re-longitudinal laparotomy was performed. Postpartum completion surgery revealed no further neoplastic cells.

2.
ACS Omega ; 4(2): 2649-2660, 2019 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-31459500

RESUMEN

The assembly of peptides and proteins into nanoscale amyloid fibrils via formation of intermolecular ß-sheets not only plays an important role in the development of degenerative diseases but also represents a promising approach for the synthesis of functional nanomaterials. In many biological and technological settings, peptide assembly occurs in the presence of organic and inorganic interfaces with different physicochemical properties. In an attempt to dissect the relative contributions of the different molecular interactions governing amyloid assembly at interfaces, we here present a systematic study of the effects of terminal modifications on the adsorption and assembly of the human islet amyloid polypeptide fragment hIAPP(20-29) at organic self-assembled monolayers (SAMs) presenting different functional groups (cationic, anionic, polar, or hydrophobic). Using a selection of complementary in situ and ex situ analytical techniques, we find that even this well-defined and comparatively simple model system is governed by a rather complex interplay of electrostatic interactions, hydrophobic interactions, and hydrogen bonding, resulting in a plethora of observations and dependencies, some of which are rather counterintuitive. In particular, our results demonstrate that terminal modifications can have tremendous effects on peptide adsorption and assembly dynamics, as well as aggregate morphology and molecular structure. The effects exerted by the terminal modifications can furthermore be modulated in nontrivial ways by the physicochemical properties of the SAM surface. Therefore, terminal modifications are an important factor to consider when conducting and comparing peptide adsorption and aggregation studies and may represent an additional parameter for guiding the assembly of peptide-based nanomaterials.

3.
Eng Life Sci ; 18(7): 510-519, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32624932

RESUMEN

Membrane bioreactors (MBRs) augmented with terrestrial white-rot basidiomycetes have already been tested for the removal of pharmaceutically active compounds (PhACs) from wastewaters. Within the present study, an aquatic ascomycete (Phoma sp.) was initially demonstrated to efficiently remove several PhACs at their real environmental trace concentrations from nonsterile municipal wastewater on a laboratory scale. Then, a pilot MBR was bioaugmented with Phoma sp. and successively operated in two configurations (first treating full-scale MBR effluent as a posttreatment, and then treating raw municipal wastewater). Treatment of influent wastewater by the Phoma-bioaugmented pilot MBR was more efficient than influent treatment by a concomitantly operated full-scale MBR lacking Phoma sp and posttreatment of full-scale MBR permeate using the pilot MBR. A stable removal of the PhACs carbamazepine (CBZ) and diclofenac (DF) (39 and 34% on average, respectively) could be achieved throughout the pilot MBR influent treatment period of 51 days, without the need for additional nutrient supplementation (full-scale MBR: on average, 15% DF but no CBZ removed during 108 days). The long-term presence of Phoma sp. in the pilot MBR could be demonstrated using fluorescence in situ hybridization analysis, but still open questions regarding its long-term activity maintenance remain to be answered.

4.
Appl Microbiol Biotechnol ; 100(5): 2381-99, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26536880

RESUMEN

The environmentally widespread micropollutants bisphenol A (BPA), carbamazepine (CBZ), 17α-ethinylestradiol (EE2), diclofenac (DF), sulfamethoxazole (SMX), technical nonylphenol (t-NP) and triclosan (TCS) were used to assess the potential of the laccase-producing freshwater ascomycete Phoma sp. strain UHH 5-1-03 for micropollutant removal and to provide quantitative insights into the mechanisms involved. Biotransformation rates observed with whole fungal cells followed the rank order EE2 ≫ BPA > TCS > t-NP > DF > SMX > CBZ. Biosorption onto fungal mycelia was prominent for BPA, EE2, TCS and t-NP and insignificant for CBZ, DF and SMX. Enzymatic removal rates investigated with cell-free, laccase-containing culture supernatants of Phoma sp. followed the rank order EE2 > BPA > DF > t-NP > TCS and were insignificant for SMX and CBZ. Mass spectrometry-assisted investigations addressing metabolite formation from unlabelled and (13)C6-labelled DF and SMX yielded DF metabolites indicating hydroxylation, cyclisation and decarboxylation reactions, as well as oxidative coupling typical for laccase reactions. For SMX, several products characterised by lower molecular masses than the parent compound were found, and indications for deamination and formamide formation were obtained. Summarising, the obtained results suggest that the extracellular laccase of Phoma sp. largely contributes to fungal biotransformation of EE2, BPA, DF, TCS and t-NP, together with cell-associated enzymes such as, e.g. cytochrome P450 monooxygenases suggested by the appearance of hydroxylated metabolites from DF. Laccase does not seem to play any role in the metabolisation of SMX and CBZ, where yet to be identified cell-associated enzymes have to be considered instead.


Asunto(s)
Ascomicetos/metabolismo , Fenómenos Químicos , Disruptores Endocrinos/metabolismo , Agua Dulce/microbiología , Contaminantes Químicos del Agua/metabolismo , Adsorción , Biotransformación , Agua Dulce/química , Espectrometría de Masas , Redes y Vías Metabólicas
5.
PLoS One ; 10(7): e0131773, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26147966

RESUMEN

Synthetic polymers often pose environmental hazards due to low biodegradation rates and resulting accumulation. In this study, a selection of wood-rotting fungi representing different lignocellulose decay types was screened for oxidative biodegradation of the polymer polystyrene sulfonate (PSS). Brown-rot basidiomycetes showed PSS depolymerisation of up to 50 % reduction in number-average molecular mass (Mn) within 20 days. In-depth investigations with the most efficient depolymeriser, a Gloeophyllum trabeum strain, pointed at extracellular hydroquinone-driven Fenton chemistry responsible for depolymerisation. Detection of hydroxyl radicals present in the culture supernatants showed good compliance with depolymerisation over the time course of PSS degradation. 2,5-Dimethoxy-1,4-hydroquinone (2,5-DMHQ), which was detected in supernatants of active cultures via liquid chromatography and mass spectrometry, was demonstrated to drive the Fenton processes in G. trabeum cultures. Up to 80% reduction in Mn of PSS where observed when fungal cultures were additionally supplemented with 2,5-dimethoxy benzoquinone, the oxidized from of 2,5-DMHQ. Furthermore, 2,5-DMHQ could initiate the Fenton's reagent-mediated PSS depolymerisation in cell-free systems. In contrast, white-rot fungi were unable to cause substantial depolymerising effects despite the expression of lignin-modifying exo-enzymes. Detailed investigations with laccase from Trametes versicolor revealed that only in presence of certain redox mediators limited PSS depolymerisation occurred. Our results indicate that brown-rot fungi might be suitable organisms for the biodegradation of recalcitrant synthetic polymeric pollutants.


Asunto(s)
Basidiomycota/química , Hongos/química , Peróxido de Hidrógeno/química , Hidroquinonas/química , Hierro/química , Poliestirenos/química , Madera/microbiología , Benzoquinonas/química , Biodegradación Ambiental , Sistema Libre de Células/química , Lignina/química , Oxidación-Reducción , Polimerizacion
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