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1.
Environ Sci Process Impacts ; 25(6): 1094-1101, 2023 Jun 21.
Article in English | MEDLINE | ID: mdl-37162184

ABSTRACT

Addition of microplastics (MP) to soil has the potential to increase soil water repellency. However, coating of MP with soil abundant substances e.g., iron compounds, can reduce this effect. Here, we tested if pre-coating or in situ coating of MP with ferrihydrite (Fh) reduces soil water repellency. We applied hotspots of pristine and coated MP (20-75 µm, PS and PET) to sand and imaged capillary rise via neutron radiography. Capillary rise experiments in wetting-drying cycles were conducted using water and Fh suspension. Pristine MP hotspots were not wettable. Capillary rise of water into coated MP hotspots differed in wettability depending on polymer type. While coated PS was still non-wettable, water imbibed into the coated PET hotspot. Capillary rise of Fh suspensions in wetting and drying cycles also showed varying results depending on polymer type. MP hotspots were still non-wettable and local water content increased only marginally. Our results indicate that Fh coating of MP changes MP surface wettability depending on polymer type and therefore counteracts the hydrophobic properties of pristine MP. However, MP coating is likely to be slowed down by the initial hydrophobicity of pristine MP. Dynamics of MP coating and increasing wettability are key factors for biotic and abiotic degradation processes.


Subject(s)
Microplastics , Soil , Soil/chemistry , Plastics , Water/chemistry
2.
RSC Adv ; 13(6): 4011-4018, 2023 Jan 24.
Article in English | MEDLINE | ID: mdl-36756587

ABSTRACT

This study establishes a preparative route towards a model system for supported catalytically active liquid metal solutions (SCALMS) on nanostructured substrates. This model is characterized by a uniquely precise geometrical control of the gallium particle size distribution. In a SCALMS system, the Ga serves as a matrix material which can be decorated with a catalytically active material subsequently. The corresponding Ga containing precursor is spin-coated on aluminum based substrates, previously nanostructured by electrochemical anodization. The highly ordered substrates are functionalized with distinct oxide coatings by atomic layer deposition (ALD) independently from the morphology. After preparation of the metal particles on the oxide interface, the characterization of our model system in terms of its geometry parameters (droplet diameter, size distribution and population density) points to SiO2 as the best suited surface for a highly controlled geometry. This flexible model system can be functionalized with a dissolved noble metal catalyst for the application chosen.

3.
J Gynecol Surg ; 38(3): 207-213, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35785107

ABSTRACT

Objective: To describe pregnancy outcomes in women who conceived after undergoing transcervical fibroid ablation (TFA) as treatment for symptomatic uterine fibroids. Materials and Methods: TFA was used to treat symptomatic uterine fibroids with radiofrequency energy, both under clinical trial protocol and commercial usage in hospitals in Europe, the United Kingdom, Mexico, and the United States. All women who reported pregnancies to their physicians after undergoing TFA with the Sonata® System and provided consent for use of their data were included. Results: There have been 36 pregnancies representing 20 deliveries among 28 women who were treated with TFA. Five women conceived more than once postablation, and four conceived as a result of assisted reproductive technology (ART). Outcomes include 8 vaginal deliveries, 12 Cesarean sections, 3 therapeutic abortions, and 8 first trimester spontaneous abortions (four occurring in a patient with a history of recurrent pregnancy loss and an immunologic disorder). Five women are currently pregnant, two of whom previously delivered after TFA. There were no 5-minute Apgar scores <7, and all neonates weighed >2500 g. All deliveries occurred at ≥37 weeks except for one delivery at 35 6/7 weeks. There were no uterine ruptures or abnormal placentation and no reports of postpartum hemorrhage or stillbirths. Ablated fibroids included transmural, submucous, and intramural myomata up to 7 cm in diameter. Conclusions: Normal pregnancy outcomes at term have occurred after TFA with the Sonata System, including in women with recurrent abortion and in those undergoing ART. There were no instances of low Apgar scores, low birthweight, stillbirth, postpartum hemorrhage, or uterine rupture (FAST-EU, NCT01226290; SONATA, NCT02228174; SAGE, NCT03 118037). (J GYNECOL SURG 38:207).

4.
Int J Gynaecol Obstet ; 155(1): 79-85, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33544889

ABSTRACT

OBJECTIVE: To examine the role and benefits of transcervical fibroid ablation (TFA) in the treatment of submucous and large uterine fibroids. METHODS: A subgroup of patients with submucous or large fibroids were analyzed from two prospective clinical trials (FAST-EU and SONATA) of sonography-guided TFA with the Sonata® system. Key outcomes were changes in menstrual blood loss, symptom severity and health-related quality of life on the Uterine Fibroid Symptom and Quality-of-Life Questionnaire, health-related quality of life on the EQ-5D questionnaire, and surgical reinterventions for heavy menstrual bleeding. RESULTS: Among 197 women (534 treated fibroids), 86% of women with only submucous fibroids and 81% of women with large fibroids (>5 cm) experienced bleeding reduction within 3 months post-ablation. Overall symptom severity and health-related quality of life showed sustained, significant improvements over 12 months. Additional fibroid mapping of large fibroids with magnetic resonance imaging in the FAST-EU trial showed an average volume reduction of 68%. Among women with only submucous fibroids, the rate of surgical reintervention through 1 year of follow up was 3.7% in FAST-EU and 0.0% in SONATA. CONCLUSION: With the Sonata system, TFA is an effective single-stage treatment option for non-pedunculated submucous myomata, and larger or deeper uterine fibroids (including fibroid clusters) for which hysteroscopic treatment is not suitable. ClinicalTrials.gov: FAST-EU, NCT01226290; SONATA, NCT02228174.


Subject(s)
Leiomyoma , Menorrhagia , Uterine Neoplasms , Female , Humans , Leiomyoma/surgery , Menorrhagia/etiology , Menorrhagia/surgery , Prospective Studies , Quality of Life , Treatment Outcome , Uterine Neoplasms/surgery
5.
J Gynecol Surg ; 35(4): 253-255, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31406455

ABSTRACT

Background: Transcervical radiofrequency (RF) ablation of uterine fibroids is an incisionless procedure to treat nonpedunculated uterine fibroids, including those that are not amenable to operative hysteroscopy. However, its safety and effectiveness regarding fertility and fecundity have not been established, including among women with infertility. Case: A 38-year-old nullipara with infertility since 2008 and a recent complaint of refractory dysmenorrhea in association with a uterine fibroid underwent transcervical RF ablation with the Sonata® System (Gynesonics, Redwood City, CA) to treat the symptomatic myoma. Unsuccessful assisted reproduction (intracytoplasmic sperm injection/embryo transfer) as confirmed by negative pregnancy testing had been attempted 1 month preablation, and a second embryo transfer after thawing the previously cryopreserved pronuclei was performed 7 months postablation. Results: RF ablation with the Sonata System resulted in a 68% reduction in fibroid volume noted on sonography 2 months post-treatment along with resolution of the patient's dysmenorrhea. No residual fibroid was noted on sonography 7 months postablation. A second attempt at assisted reproduction produced an uncomplicated pregnancy that resulted in vacuum-assisted vaginal delivery of a liveborn infant at term weighing 3670 g with Apgar scores of 91/105/1010. Pelvic sonography 4 months postpartum an unremarkable uterus, again, with no evidence of a fibroid remnant. Conclusions: This is the first report of a pregnancy and delivery in an infertile couple who underwent transcervical RF ablation of a uterine fibroid followed by assisted reproduction.

6.
NMR Biomed ; 17(7): 500-6, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15523717

ABSTRACT

The purpose of this study was to study different doses for first-pass and equilibrium phase MRA of aortoiliac vessels with a superparamagnetic iron oxide (SPIO) intravascular MR contrast agent (SH U 555 C) after single i.v. bolus injection. Sixteen healthy volunteers were prospectively enrolled into this single-blind, placebo-controlled clinical trial. SHU 555 C was injected as an i.v. bolus at stepwise increased dose levels of 5, 10, 20 and 40 micromol Fe/kg bodyweight (b.w.) corresponding to injection volumes of 0.01, 0.02, 0.04 and 0.08 ml/kg b.w. Serial high-resolution three-dimensional MRA of the aortoiliac vessels was acquired during first-pass and equilibrium, at 6 min intervals up to 42 min after contrast application using a breath-hold three-dimensional FLASH sequence on a 1.5 T scanner. Intravascular enhancement was calculated within the abdominal aorta and the inferior vena cava and a statistical analysis for significant differences in vessel enhancement was performed during the bolus and equilibrium phases. The visibility of vessels was ranked and effects of potential artifacts on image quality were graded for each time point and dose group. SH U 555 C showed a dose-dependent intravascular enhancement during the observation period (42 min). The highest dose of 40 micromol Fe/kg b.w. revealed the highest image quality during first-pass and equilibrium phases. The intravascular enhancement in the aorta increased dose-dependently from 5 to 40 micromol kg b.w. during first-pass and equilibrium phases (p<0.05). Intravascular signal inhomogeneities were observed at lower doses and decreased with increasing doses. First-pass MRA was diagnostic at doses of 10, 20 and 40 micromol Fe/kg b.w. For equilibrium MRA, a dose of 40 micromol Fe/kg b.w. was considered to be diagnostic. SH U 555 C proved to be a contrast agent with a high T1-effect suitable for both first-pass MRA comparable to gadolinium-enhanced MRA and high resolution equilibrium MRA up to 42 min post-injection (p.i.).


Subject(s)
Aorta/anatomy & histology , Contrast Media , Ferric Compounds , Iliac Artery/anatomy & histology , Image Interpretation, Computer-Assisted/methods , Magnetic Resonance Angiography/methods , Adult , Dose-Response Relationship, Drug , Ferric Compounds/administration & dosage , Humans , Image Enhancement/methods , Male , Single-Blind Method
7.
Radiology ; 231(2): 474-81, 2004 May.
Article in English | MEDLINE | ID: mdl-15044749

ABSTRACT

PURPOSE: To evaluate SH U 555 C for contrast material-enhanced three-dimensional magnetic resonance (MR) angiography of the chest and myocardial perfusion. MATERIALS AND METHODS: For chest MR angiography, SH U 555 C was intravenously injected at four doses (5, 10, 20, and 40 micromol iron [Fe] per kilogram of body weight) into three healthy volunteers per dose group, and placebo (saline) was injected into one additional volunteer per dose group (16 subjects). With a body phased-array coil, serial high-spatial-resolution breath-hold three-dimensional MR angiography of the chest was performed at baseline, first pass, and 6, 12, 18, 24, 30, 36, and 42 minutes after injection. SH U 555 C (40 micromol Fe/kg) was injected into four additional volunteers to evaluate cardiac perfusion. Signal intensity (SI) was measured in vessels, cardiac chambers, and myocardium to calculate relative SI changes during time. Analysis of variance for multiple comparisons was applied for statistical analysis. Two readers assessed image quality. Subjects were monitored for side effects (cardiovascular reactions) for 24 hours. RESULTS: SH U 555 C showed a dose-dependent increase in SI enhancement during first pass and equilibrium phase. SH U 555 C showed dose-dependent increase (range, 259% +/- 160 [SD] at 5 micromol Fe/kg to 907% +/- 370 at 40 micromol Fe/kg) for thoracic aorta during first pass. Intravascular SI did not significantly decrease with time during equilibrium phase within arterial and venous vessels. Image quality remained stable and was diagnostic for highest dose group to 30 minutes, with good to excellent contrast even in smaller blood vessels. For cardiac perfusion, SH U 555 C showed peak enhancement during first pass through right and left ventricles, as well as stable SI during equilibrium phase within cardiac chambers and myocardium. Peak enhancement during first pass was limited due to susceptibility effects, which were more pronounced in right ventricle than in left. Contrast agent was well tolerated, and no cardiovascular reactions occurred. CONCLUSION: SH U 555 C bolus injected at highest dose of 40 micromol Fe/kg has capability for depiction at first-pass MR angiography and for cardiac perfusion.


Subject(s)
Contrast Media , Coronary Circulation , Iron , Magnetic Resonance Angiography , Oxides , Adult , Dextrans , Ferrosoferric Oxide , Humans , Magnetite Nanoparticles , Male , Thorax
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