Publications by authors named "Stephanie Ehlers"

5 Publications

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[Epidemiology and treatment of retinopathy of prematurity. The Hannover data in the Retina.net ROP registry from 2001-2017].

Ophthalmologe 2021 Nov 22. Epub 2021 Nov 22.

Universitätsklinik für Augenheilkunde, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Deutschland.

Background: The Retina.net ROP registry documents data of preterm infants developing stages of retinopathy of prematurity (ROP) that need ROP treatment. The aim of this analysis was to investigate data regarding epidemiology, therapy and changes over time (15 years) in a single participating center (Hannover Medical School, MHH).

Methods: Analysis of data of infants treated for ROP at a single center over time (birth 2001-2016, ROP treatment in 2002-2017).

Results: Overall, 65 infants were treated (23 female). In 11 infants (16.9%) ROP screening was conducted externally and infants were transferred to the MHH for ROP treatment. Between 2006 and 2016, incidence of ROP requiring treatment among infants screened for the development of ROP was 4.1%. Mean gestational age was 25.7 weeks (standard deviation, SD 1.8), mean birth weight 763 g (SD 235), postmenstrual age at treatment 38.2 weeks (SD 3.2), postnatal age 12.4 weeks (SD 3.2). There was no significant change in parameters over time. ROP zone II, stage 3+ was most frequently treated (57 eyes of 31 infants). 58 infants were treated with laser (114 eyes), 7 infants were treated with anti-VEGF (bevacizumab, bilateral, 14 eyes) from 2014 onwards. Retreatment due to recurrence of ROP was necessary in one infant after initial laser coagulation. Infants with ROP requiring treatment often presented with neonatal comorbidities, ventilation in more than 90%, bronchopulmonary dysplasia, and received transfusions.

Conclusion: This is the first monocentric analysis over 15 years originating from the Retina.net ROP registry. In this cohort we see a change in ROP therapy from laser coagulation to anti-VEGF (bevacizumab) from 2014 onwards, demographic data and treatment parameters remained relatively stable over time.
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http://dx.doi.org/10.1007/s00347-021-01528-9DOI Listing
November 2021

Identification and Composition of Clasper Scent Gland Components of the Butterfly Heliconius erato and Its Relation to Mimicry.

Chembiochem 2021 Dec 8;22(23):3300-3313. Epub 2021 Oct 8.

Technische Universität Braunschweig, Hagenring 30, 38106, Braunschweig, Germany.

The butterfly Heliconius erato occurs in various mimetic morphs. The male clasper scent gland releases an anti-aphrodisiac pheromone and additionally contains a complex mixture of up to 350 components, varying between individuals. In 114 samples of five different mimicry groups and their hybrids 750 different compounds were detected by gas chromatography/mass spectrometry (GC/MS). Many unknown components occurred, which were identified using their mass spectra, gas chromatography/infrared spectroscopy (GC/IR)-analyses, derivatization, and synthesis. Key compounds proved to be various esters of 3-oxohexan-1-ol and (Z)-3-hexen-1-ol with (S)-2,3-dihydrofarnesoic acid, accompanied by a large variety of other esters with longer terpene acids, fatty acids, and various alcohols. In addition, linear terpenes with up to seven uniformly connected isoprene units occur, e. g. farnesylfarnesol. A large number of the compounds have not been reported before from nature. Discriminant analyses of principal components of the gland contents showed that the iridescent mimicry group differs strongly from the other, mostly also separated, mimicry groups. Comparison with data from other species indicated that Heliconius recruits different biosynthetic pathways in a species-specific manner for semiochemical formation.
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http://dx.doi.org/10.1002/cbic.202100372DOI Listing
December 2021

Extending the Salinilactone Family.

Chembiochem 2020 06 10;21(11):1629-1632. Epub 2020 Mar 10.

Institut für Organische Chemie, TU Braunschweig, Hagenring 30, 38106, Braunschweig, Germany.

Five new members of the salinilactone family, salinilactones D-H, are reported. These bicyclic lactones are produced by Salinispora bacteria and display extended or shortened alkyl side chains relative to the recently reported salinilactones A-C. They were identified by GC/MS, gas chromatographic retention index, and comparison with synthetic samples. We further investigated the occurrence of salinilactones across six newly proposed Salinispora species to gain insight into how compound production varies among taxa. The growth-inhibiting effect of this compound family on multiple biological systems including non-Salinispora actinomycetes was analyzed. Additionally, we found strong evidence for significant cytotoxicity of the title compounds.
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http://dx.doi.org/10.1002/cbic.201900764DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7317194PMC
June 2020

Ring-Opening Reactions of Donor-Acceptor Cyclobutanes with Electron-Rich Arenes, Thiols, and Selenols.

Org Lett 2019 Aug 5;21(16):6315-6319. Epub 2019 Aug 5.

Donor-acceptor (D-A) cyclobutanes with two geminal ester groups as acceptors are reacted with electron-rich arenes as nucleophiles to afford ring-opened products. AlCl mediates this Friedel-Crafts-type reaction. A variety of donors and electron-rich arenes are used. Nucleophilic thiols and selenols also trigger this ring-opening reaction. Furthermore, a comparison of various physical parameters has been carried out for several D-A cyclobutanes.
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http://dx.doi.org/10.1021/acs.orglett.9b02197DOI Listing
August 2019

Granulocyte colony-stimulating factor (G-CSF) treatment of childhood acute myeloid leukemias that overexpress the differentiation-defective G-CSF receptor isoform IV is associated with a higher incidence of relapse.

J Clin Oncol 2010 May 20;28(15):2591-7. Epub 2010 Apr 20.

Department of Pediatric Hematology and Oncology, Medical School Hannover, Hannover, Germany.

Purpose: This prospective, multicenter Acute Myeloid Leukemia Berlin-Frankfurt-Muenster (AML-BFM) 98 study randomly tested the ability of granulocyte colony-stimulating factor (G-CSF) to reduce infectious complications and to improve outcomes in children and adolescents with acute myeloid leukemia (AML). However, a trend toward an increased incidence of relapses in the standard-risk (SR) group after G-CSF treatment was observed.

Patients And Methods: Of 154 SR patients in the AML-BFM 98 cohort, 50 patients were tested for G-CSF receptor (G-CSFR) RNA isoform I and IV expression, G-CSFR cell surface expression, and acquired mutations in the G-CSFR gene.

Results: In patients randomly assigned to receive G-CSF after induction, 16 patients overexpressing the G-CSFR isoform IV showed an increased 5-year cumulative incidence of relapse (50% +/- 13%) compared with 14 patients with low-level isoform IV expression (14% +/- 10%; log-rank P = .04). The level of G-CSFR isoform IV had no significant effect in patients not receiving G-CSF (P = .19). Multivariate analyses of the G-CSF-treated subgroup, including the parameters G-CSFR isoform IV overexpression, sex, and favorable cytogenetics as covariables, revealed the prognostic relevance of G-CSFR isoform IV overexpression for 5-year event-free survival (P = .031) and the 5-year cumulative incidence of relapse (P = .049).

Conclusion: Our results demonstrate that children and adolescents with AMLs that overexpress the differentiation-defective G-CSFR isoform IV respond to G-CSF administration after induction, but with a significantly higher incidence of relapse.
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http://dx.doi.org/10.1200/JCO.2009.25.9010DOI Listing
May 2010
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