Lifestyle intervention prior to IVF does not improve embryo utilization rate and cumulative live birth rate in women with obesity: a nested cohort study

Study Question: Does lifestyle intervention consisting of an energy-restricted diet, enhancement of physical activity and motivational counseling prior to IVF improve embryo utilization rate (EUR) and cumulative live birth rate (CLBR) in women with obesity? Summary Answer: A 6-month lifestyle intervention preceding IVF improved neither EUR nor CLBR in women with obesity in the first IVF treatment cycle where at least one oocyte was retrieved. What Is Known Already: A randomized controlled trial (RCT) evaluating the efficacy of a low caloric liquid formula diet (LCD) preceding IVF in women with obesity was unable to demonstrate an effect of LCD on embryo quality and live birth rate: in this study, only one fresh embryo transfer (ET) or, in case of freeze-all strategy, the first transfer with frozen-thawed embryos was reported. We hypothesized that any effect on embryo quality of a lifestyle intervention in women with obesity undergoing IVF treatment is better revealed by EUR and CLBR after transfer of all fresh and frozen-thawed embryos. Study Design, Size, Duration: This is a nested cohort study within an RCT, the LIFEstyle study. The original study examined whether a 6-month lifestyle intervention prior to infertility treatment in women with obesity improved live birth rate, compared to prompt infertility treatment within 24 months after randomization. In the original study between 2009 and 2012, 577 (three women withdrew informed consent) women with obesity and infertility were assigned to a lifestyle intervention followed by infertility treatment (n = 289) or to prompt infertility treatment (n = 285). Participants/Materials, Setting, Methods: Only participants from the LIFEstyle study who received IVF treatment were eligible for the current analysis. In total, 137 participants (n = 58 in the intervention group and n = 79 in the control group) started the first cycle. In 25 participants, the first cycle was cancelled prior to oocyte retrieval mostly due to poor response. Sixteen participants started a second or third consecutive cycle. The first cycle with successful oocyte retrieval was used for this analysis, resulting in analysis of 51 participants in the intervention group and 72 participants in the control group. Considering differences in embryo scoring methods and ET day strategy between IVF centers, we used EUR as a proxy for embryo quality. EUR was defined as the proportion of inseminated/injected oocytes per cycle that was transferred or cryopreserved as an embryo. Analysis was performed per cycle and per oocyte/embryo. CLBR was defined as the percentage of participants with at least one live birth from the first fresh and subsequent frozen-thawed ET(s). In addition, we calculated the Z-score for singleton neonatal birthweight and compared these outcomes between the two groups. Main Results and the Role Of Chance: The overall mean age was 31.6 years and the mean BMI was 35.4 ± 3.2 kg/m2 in the intervention group, and 34.9 ± 2.9 kg/m2 in the control group. The weight change at 6 months was in favor of the intervention group (mean difference in kg vs the control group: −3.14, 95% CI: −5.73 to −0.56). The median (Q25; Q75) number of oocytes retrieved was 4.00 (2.00; 8.00) in the intervention group versus 6.00 (4.00; 9.75) in the control group, and was not significantly different, as was the number of oocytes inseminated/injected (4.00 [2.00; 8.00] vs 6.00 [3.00; 8.75]), normal fertilized embryos (2.00 [0.50; 5.00] vs 3.00 [1.00; 5.00]) and the number of cryopreserved embryos (2.00 [1.25; 4.75] vs 2.00 [1.00; 4.00]). The median (Q25; Q75) EUR was 33.3% (12.5%; 60.0%) in the intervention group and 33.3% (16.7%; 50.0%) in the control group in the per cycle analysis (adjusted B: 2.7%, 95% CI: −8.6% to 14.0%). In the per oocyte/embryo analysis, in total, 280 oocytes were injected or inseminated in the intervention group, 113 were utilized (transferred or cryopreserved, EUR = 40.4%); in the control group, EUR was 30.8% (142/461). The lifestyle intervention did not significantly improve EUR (adjusted odds ratio [OR]: 1.36, 95% CI: 0.94–1.98) in the per oocyte/embryo analysis, taking into account the interdependency of the oocytes per participant. CLBR was not significantly different between the intervention group and the control group after adjusting for type of infertility (male factor and unexplained) and smoking (27.5% vs 22.2%, adjusted OR: 1.03, 95% CI: 0.43–2.47). Singleton neonatal birthweight and Z-score were not significantly different between the two groups. Limitations, Reasons for Caution: This study is a nested cohort study within an RCT, and no power calculation was performed. The randomization was not stratified for indicated treatment, and although we corrected our analyses for baseline differences, there may be residual confounding. The limited absolute weight loss and the short duration of the lifestyle intervention might be insufficient to affect EUR and CLBR. Wider Implications of the Findings: Our data do not support the hypothesis of a beneficial short-term effect of lifestyle intervention on EUR and CLBR after IVF in women with obesity, although more studies are needed as there may be a potential clinically relevant effect on EUR.Zheng Wang, Henk Groen, Koen C. Van Zomeren, Astrid E.P. Cantineau, Anne Van Oers, Aafke P.A. Van Montfoort, Walter K.H. Kuchenbecker, Marie J. Pelinck, Frank J.M. Broekmans, Nicole F. Klijn, Eugenie M. Kaaijk, Ben W.J. Mol, Annemieke Hoek, and Jannie Van Echten-Arend

New sulfide catalysts for the hydroliquefaction of coal

Possibilities for the preparation of new metal sulfide catalyst systems based on carbon carriers having favourable textural and surface properties have been explored, and attention has been given to the characterization (structure) and evaluation (hydrosulfurization activity) of these catalysts. Two different types of carbon carriers were prepared viz., carbon black composite and carbon-covered alumina. The influence of various carbon carrier oxidative treatments on the activity of the supported sulfide phase has been studied. For the characterization of the structure of the active (Mo) sulfide phase deposited on an (activated) carbon carrier a combination of dynamic oxygen chemisorption, thiophene hydro desulfurization and X-ray photoelectron spectroscopy measurements was applied. Carbon black composites having outstanding textural properties for the application as support material for molybdenum sulfide catalysts could be prepared. The Inertness of their surface appeared to be a drawback for obtaining h'igh catalytic activity. However, catalytic activity was considerably improved after the reactivity of the carbon surface towards the molybdenum phase was Increased by means of an oxidative treatment. The carbon-covered aluminas prepared had promising textural properties. Covering the alumina surface by a layer of pyrolitlc carbon was found to improve the activity of supported (cobalt) sulfide phase. In none of the carboncovered aluminas prepared the alumina surface was completely covered since the carbon was not uniformly deposited. Therefore the maximum effect of the carbon coverage on the catalytic activity was never reached. However, heat treatment of the pyrolitic carbon appeared beneficial in this case. The results of dynamic oxygen chemisorption measurements showed that the molybdenum sulfide phase supported on active carbon had a high density of only one type of active site with a high turn over frequency. The alumina supported molybdenum phase had a lower active site density and different types of sites seemed to be present at low and high molybdenum concentration. For both the Mo/C and Mo/¿-Al2O3 catalysts, the decline in activity with run time was not reproduced by the oxygen chemisorption capacities. Thus Initial deactivation was neither caused by sintering of the active phase nor by pore blocking

Characterization of silica-supported molybdenum oxide and tungsten oxide. Reducibility of the oxidic state versus hydrodesulfurization activity of the sulfided state

Thiophene hydrodesulfurization and butene hydrogenation have been studied for presulfided MoO3/SiO2 and WO3/SiO2 catalysts using a micro-flow reactor operating at atmospheric pressure. The catalysts have been prepared by dry as well as wet impregnation. The oxidic precursor catalysts were characterized by X-ray diffraction, surface area and pore volume measurements, and temperature-programmed reduction. Catalysts prepared by dry or wet impregnation are essentially the same. At low metal oxide contents the catalysts are of the monolayer type. At higher metal oxide contents also bulk compounds are present, which is demonstrated by means of X-ray diffraction as well as temperature-programmed reduction. The maximum concentration of monolayer-type compounds corresponds to approximately one transition metal atom per square nanometer of the carrier. A correlation could be established between reducibility of the oxidic monolayer-type catalysts and the activity for thiophene hydrodesulfurization. This correlation appears to be in good agreement with the one reported earlier for the analogous ¿-alumina-based catalysts. Butene hydrogenation activity of the sulfided MoO3/SiO2 and WO3/SiO2 monolayer-type catalysts also correlates with reducibility of the oxidic systems. Due to the presence of bulk compounds the turnover frequency in hydrodesulfurization as well as hydrogenation decreases at higher metal oxide contents

Study of porous structure of pillared clays: 1. Montmorillonite fixed by chromium (III) oxide

The porous structure of montmorillonite fixed by chromium oxide was studied by nitrogen, water vapor, and benzene adsorption.The adsorption data obtained were analyzed in detail by the cr"-method and the theory of volume fllling of micropores. The fixation of acid-treated montmorillonite K 10 by hydroxochromium cations resulted in the formation of the pillared clay with considerable mesoporosity. Additional micropores appeared, and new polar adsorption sites were formed. The role of new absorption sites belongs to hydroxochromium cations or chromium oxide clusters localized in the interlayer space of the pillared clay. A microporous material was found to be formed mostly by the fixation of Oglanli bentonite. Thecalcination of the synthesized pillared clays at 673 K resulted in an increase in the average width of their micropores and mesoporosity. The porous montmorillonite structure fixed by chromium oxide can be purposefully formed using clays of different chemical composition and physical and chemical properties

Chromia- and chromium sulfide-pillared clays : preparation, characterization, and catalytic activity for thiophene hydrodesulfurization

Chromia-pillared clay has been synthesized from naturally occurring montmorillonite through exchange of interlamellar ions with hydroxychromium polycations. Sulfidation of the heat-treated precursor with an H2S–H2mixture at 673 K results in the formation of chromium sulfide-pillared clay. The materials were characterized by X-ray diffraction, thermogravimetric analysis, nitrogen adsorption, scanning electron microscopy, electron probe microanalysis, and X-ray photoelectron spectroscopy. These methods showed that heat treatment of chromia-pillared clay under the conditions applied did not drastically change the pore structure or the chromium oxidation state and the distribution of pillars, but strongly influenced its aggregate morphology. Sulfide-pillared material has an interlamellar distance of 1.01 nm, a BET surface area of 256 m2g-1, a micropore volume of 0.082 cm3g-1, and a pore slitwidth of 1.24 nm. The sulfidation procedure does not significantly change the pillared structure or the chromium oxidation state. Sulfur is found to be present as practically uniformly distributed S2-species. The chromium sulfide phase in the finely dispersed and well-distributed state that is reached in sulfide-pillared clay is of primary importance to the high thiophene conversion over this catalyst. In the presence of this catalyst, thiophene hydrodesulfurization results exclusively in the formation of butane and butene. The distribution of hydrocarbons depends on the reaction temperature, with a higher butane yield at lower temperature

Chromia- and chromium sulfide-pillared clays : preparation, characterization, and catalytic activity for thiophene hydrodesulfurization

Chromia-pillared clay has been synthesized from naturally occurring montmorillonite through exchange of interlamellar ions with hydroxychromium polycations. Sulfidation of the heat-treated precursor with an H2S–H2mixture at 673 K results in the formation of chromium sulfide-pillared clay. The materials were characterized by X-ray diffraction, thermogravimetric analysis, nitrogen adsorption, scanning electron microscopy, electron probe microanalysis, and X-ray photoelectron spectroscopy. These methods showed that heat treatment of chromia-pillared clay under the conditions applied did not drastically change the pore structure or the chromium oxidation state and the distribution of pillars, but strongly influenced its aggregate morphology. Sulfide-pillared material has an interlamellar distance of 1.01 nm, a BET surface area of 256 m2g-1, a micropore volume of 0.082 cm3g-1, and a pore slitwidth of 1.24 nm. The sulfidation procedure does not significantly change the pillared structure or the chromium oxidation state. Sulfur is found to be present as practically uniformly distributed S2-species. The chromium sulfide phase in the finely dispersed and well-distributed state that is reached in sulfide-pillared clay is of primary importance to the high thiophene conversion over this catalyst. In the presence of this catalyst, thiophene hydrodesulfurization results exclusively in the formation of butane and butene. The distribution of hydrocarbons depends on the reaction temperature, with a higher butane yield at lower temperature