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Baldewijns K, Vandenhoudt H, Nijst P, Vercammen J, Van Laethem M, Haumont L, Vandepoel I, Moldenaers I, Brunner La-Rocca HP, Smeets M. enhancing primary Care: development of a Training for primary care nurses in heart failure Education. Eur J Cardiovasc Nurs 2022. [DOI: 10.1093/eurjcn/zvac060.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): King Baudouin Foundation Belgium
Background, Self-care in Heart Failure (HF) is important to prevent rehospitalisation and to improve Quality of Life (QoL).1, 2 Therefore, it is necessary that HF-patients receive continuous education and self-care support, both in the hospital as at home.3 In Belgium, multidisciplinary (Mdisc-) HF-programmes are not yet broadly implemented, nor does a national HF-DMP exists. Specialist HF-nurses are not readily available and GPs report that they do not have time for patient education . 4,5 GPs identified trained primary care nurses (PCN) as their preferred partner to take on patient education and self-care support.5 However, currently, these nurses are not trained to take on this role.5
Purpose
To develop an evidence-based HF-educator training for primary care nurses.
Methods
The training was developed in 10 consecutive steps:
Step 1, a working group with representatives of Belgian HF-cardiologists, HF-nurses, PCN and the nursing department of a university of applied sciences was established.
Step 2, in preparation of this working group, M., a PCN and primary care HF-nurse, reviewed the curriculum of the specialist HF-nurse training to identify the (non-) relevant topics for PCN training. She presented her findings during working group 1 in which we decided to consult the primary health care professionals.
Step 3, one group interview with PCN, one interview with a GP and a diabetes educator took place. A short interview guide was developed. The main conclusions were that PCN have limited awareness for HF, it should be a short in time training, psychosocial aspects are very important, PCN should be able to detect signs and symptoms of HF, a basic module on HF must be included.
Step 4, presentation of these results to the working group.
Step 5, development of an organisational framework
Step 6, a subgroup consisting of one specialist HF-nurse, one HF-educator- and HF-nurse in primary care developed a programme based on the results of the interviews, the HFA-curriculum and the organisational framework.
Step 7, this programme was presented to and approved by the working group
Step 8, representatives of the university of applied sciences will implement the programme as part of their life-long learning programme.
Step 9 and 10: pilot and evaluation.
Results
The PCN HF-educator education will take 20h in 3 consecutive weeks. Participants will receive a theoretical introduction in HF followed by intensive practical training on patient-education, self-care and psychosocial support. In March 2022 the first pilot will take place.
Conclusions
Continuous education is important to support patients in their self-care and self-management. Therefore, it is necessary to train and support primary health care professionals in order to prepare them for this tasks. We presented a co-creative methodology to develop and implement a training for health care professionals.
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Affiliation(s)
| | - H Vandenhoudt
- Thomas More University of applied sciences , Health Care Department , Turnhout , Belgium
| | - P Nijst
- Hospital Oost-Limburg (ZOL) , Genk , Belgium
| | - J Vercammen
- Hospital Oost-Limburg (ZOL) , Genk , Belgium
| | - M Van Laethem
- Wit-Gele Kruis, Afdeling Oost-Vlaanderen , Dendermonde , Belgium
| | - L Haumont
- University College Leuven Limburg, Nursing Department , Genk , Belgium
| | - I Vandepoel
- University College Leuven Limburg, Nursing Department , Leuven , Belgium
| | - I Moldenaers
- University College Leuven Limburg, Nursing Department , Genk , Belgium
| | - H P Brunner La-Rocca
- Maastricht University Medical Centre (MUMC), Department of Cardiology , Maastricht , Netherlands (The)
| | - M Smeets
- University of Leuven, Academic Centre for General Practice , Leuven , Belgium
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Daenens V, Vercammen J, Debrock S, Bafort C, Meuleman C, D’Hooghe T, Va. Calster B, Tomassetti C. P–330 Live birth after ART in patients with treated endometriosis versus those without endometriosis at laparoscopy. Hum Reprod 2021. [DOI: 10.1093/humrep/deab130.329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Study question
Is endometriosis related to worse outcome of assisted reproductive techniques (ART)?
Summary answer
Cumulative incidence of live birth in patients with and without endometriosis at laparoscopy was similar, although deep endometriosis and adenomyosis were negative prognostic factors.
What is known already
Whether endometriosis has a negative impact on the outcome of ART is still a matter of debate. Most published data report on one fresh cycle only, usually without taking frozen embryos into account. Further, a large heterogeneity in study population has been acknowledged by several meta-analyses, as in the control groups endometriosis was not always excluded by laparoscopy, and in case of endometriosis the prior treatment history was variable or unclear.
Study design, size, duration
Retrospective longitudinal cohort study of 1462 patients (779 with laparoscopically treated endometriosis of any rASRM stage, and 683 without endometriosis at laparoscopy) undergoing ART treatment between July 2003 and December 2014. Primary outcome studied was time to ART live birth. Secondary outcomes include -amongst others- number of cycles needed per ART live birth, time to ART or spontaneous live birth, cycle cancellation rate, and pregnancy outcomes like miscarriage and ectopic pregnancy, and per cycle analyses.
Participants/materials, setting, methods
All patients with a history of laparoscopy prior to the start of their first ART were included for analysis. The ART was performed in a tertiary referral center of a large University Hospital. Primary outcome studied was the time from initiation of the first ART cycle to delivery of the first live born. Survival analysis was conducted using cumulative incidence functions and cause-specific hazards regression.
Main results and the role of chance
The study included 1462 patients who initiated 4537 ART cycles, of which 3672 (81%) fresh and 857 (19%) frozen cycles. The unadjusted hazard ratio (HR) of live birth was 1.01 (95% CI 0.88–1.16). After adjustment for potential confounders (age, maternal BMI, maternal smoking, secondary infertility, duration of infertility, anovulation, reduced ovarian reserve, tubal factor, male factor and therapy started before 2007) the HR was 0.99 (95% CI 0.86–1.14). Within the endometriosis population (n = 779), covariate-adjusted analyses suggested that presence of adenomyosis (HR = 0.54; 95% CI 0.34–0.86) and a history of deep endometriosis (HR = 0.74 – 95% CI 0.58–0.94) were associated with a lower cumulative incidence of live birth. In contrast, there was little support of an association with diagnosis of stage III/IV (HR = 1.15; 95% CI 0.84–1.59) or a history of ovarian endometriosis (HR = 0.97; 95% CI 0.72–1.30). Beside the effect of the different variables directly linked to endometriosis, maternal BMI (HR = 0.80; 95%CI 0.71–0.91) and smoking (HR = 0.69; 95%CI 0.52–0.92) also negatively affected live birth delivery rate per patient.
Limitations, reasons for caution
Practices and success rates of ART may have changed during the 11-year recruitment period. Restricting to women who underwent laparoscopy, while providing evidence of the presence or absence of endometriosis, may have induced selection bias. However, the advantage of this time period, was the high rate of pre-ART laparoscopy (+/–50%).
Wider implications of the findings: As deep endometriosis and adenomyosis represent negative prognostic factors within the endometriosis population, future studies should focus on optimalisation of ART in these subgroups.
Trial registration number
S57393
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Affiliation(s)
- V Daenens
- UZ Leuven, Obstetrics and Gynaecology, Leuven, Belgium
| | - J Vercammen
- Heilig Hartziekenhuis Mol, Obstetrics and Gynaecology, Mol, Belgium
| | - S Debrock
- UZ Leuven, Obstetrics and Gynaecology, Leuven, Belgium
| | - C Bafort
- UZ Leuven, Obstetrics and Gynaecology- Department of Development and Regeneration, Leuven, Belgium
| | - C Meuleman
- UZ Leuven, Obstetrics and Gynaecology- Department of Development and Regeneration, Leuven, Belgium
| | - T D’Hooghe
- UZ Leuven, Development and Regeneration, Leuven, Belgium
| | - B Va. Calster
- UZ Leuven, Development and Regeneration, Leuven, Belgium
| | - C Tomassetti
- UZ Leuven, Obstetrics and Gynaecology- Department of Development and Regeneration, Leuven, Belgium
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Ceulemans D, Thijs I, Schreurs A, Vercammen J, Lannoo L, Deprest J, Richter J, De Catte L, Devlieger R. Screening for COVID-19 at childbirth: is it effective? Ultrasound Obstet Gynecol 2020; 56:113-114. [PMID: 32449230 DOI: 10.1002/uog.22099] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 05/12/2020] [Accepted: 05/16/2020] [Indexed: 06/11/2023]
Affiliation(s)
- D Ceulemans
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium
- Department of Obstetrics and Gynaecology, University Hospitals Leuven, Leuven, Belgium
| | - I Thijs
- Department of Obstetrics and Gynaecology, AZ Diest, Diest, Belgium
| | - A Schreurs
- Department of Obstetrics and Gynaecology, Jessa Hospital, Hasselt, Belgium
| | - J Vercammen
- Department of Obstetrics and Gynaecology, Heilig Hartziekenhuis Mol, Mol, Belgium
| | - L Lannoo
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium
- Department of Obstetrics and Gynaecology, University Hospitals Leuven, Leuven, Belgium
| | - J Deprest
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium
- Department of Obstetrics and Gynaecology, University Hospitals Leuven, Leuven, Belgium
- Department of Obstetrics and Gynaecology, Fetal Medicine Unit, University College London Hospital, London, UK
- Institute for Women's Health, University College London, London, UK
| | - J Richter
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium
- Department of Obstetrics and Gynaecology, University Hospitals Leuven, Leuven, Belgium
| | - L De Catte
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium
- Department of Obstetrics and Gynaecology, University Hospitals Leuven, Leuven, Belgium
| | - R Devlieger
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium
- Department of Obstetrics and Gynaecology, University Hospitals Leuven, Leuven, Belgium
- Department of Obstetrics, Gynaecology and Fertility, Gasthuiszusters Antwerpen, Wilrijk, Belgium
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Buts K, Hertog ML, Ho QT, America AH, Cordewener J, Vercammen J, Carpentier SC, Nicolai B. Influence of pre-harvest calcium, potassium and triazole application on the proteome of apple at harvest. J Sci Food Agric 2016; 96:4984-4993. [PMID: 26865255 DOI: 10.1002/jsfa.7664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 08/24/2015] [Accepted: 02/02/2016] [Indexed: 06/05/2023]
Abstract
BACKGROUND Braeburn browning disorder is a storage disease characterised by flesh browning and lens-shaped cavities. The incidence of this postharvest disorder is known to be affected by pre-harvest application of fertilisers and triazole-based fungicides. Recent work has shown that calcium and potassium reduced the incidence of Braeburn browning disorder, while triazoles had the opposite effect. This study addresses the hypothesis of an early proteomic imprint in the apple fruit at harvest induced by the pre-harvest factors applied. If so, this could be used for an early screening of apple fruit at harvest for their postharvest susceptibility to flesh browning. RESULTS Calcium and triazole had significant effects, while potassium did not. One hundred and thirty protein families were identified, of which 29 were significantly altered after calcium and 63 after triazole treatment. Up-regulation of important antioxidant enzymes was correlated with calcium fertilisation, while triazole induced alterations in the levels of respiration and ethylene biosynthesis related proteins. CONCLUSION Pre-harvest fertiliser and fungicide application had considerable effects on the apple proteome at harvest. These changes, together with the applied storage conditions will determine whether or not BBD develops. © 2016 Society of Chemical Industry.
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Affiliation(s)
- Kim Buts
- BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, 3001, Heverlee, Belgium
| | | | - Quang Tri Ho
- BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, 3001, Heverlee, Belgium
| | | | - Jan Cordewener
- WUR, PRI, Droevendaalsesteeg 1, 6708, PB, Wageningen, The Netherlands
| | - Jef Vercammen
- pcfruit vzw, Fruittuinweg 1, 3800, Sint-Truiden, Belgium
| | - Sebastien C Carpentier
- SYBIOMA, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
- BIOSYST-Crop Biotechnics, KU Leuven, Willem de Croylaan 42, 3001, Heverlee, Belgium
| | - Bart Nicolai
- BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, 3001, Heverlee, Belgium
- VCBT, Willem de Croylaan 42, 3001, Heverlee, Belgium
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5
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Vandermarken T, De Galan S, Croes K, Van Langenhove K, Vercammen J, Sanctorum H, Denison MS, Goeyens L, Elskens M, Baeyens W. Characterisation and implementation of the ERE-CALUX bioassay on indoor dust samples of kindergartens to assess estrogenic potencies. J Steroid Biochem Mol Biol 2016; 155:182-9. [PMID: 25595043 DOI: 10.1016/j.jsbmb.2015.01.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 12/18/2014] [Accepted: 01/11/2015] [Indexed: 11/24/2022]
Abstract
Estrogen-like endocrine disrupting chemicals (EEDCs) can be found abundantly in the environment. Due to their low-dose effects and the large amount of unknown EEDCs, it is difficult to assess and manage possible human health risks. For young children, who are particularly vulnerable to endocrine disruption due to their development rate, indoor dust is one of the main routes of exposure. In this study, an estrogen responsive elements chemically activated luciferase gene expression (ERE-CALUX) bioassay was characterized and implemented for the analysis of 12 dust samples from kindergartens in Flanders and Brussels (Belgium). The human ovarian carcinoma BG 1CALUX cell line showed reproducible results and a low limit of detection (LOD). The effective concentration at 50% of the maximum response (EC50) yielded 497 fg/well, while the LOD was 16 fg/well. For all dust samples, full dose-response curves and their corresponding EC50 values could be calculated. All samples yielded bio-analytical equivalent concentrations (BEQs) that were significantly higher than the procedural blank level and ranged from 426 to 8710 pg E2 equivalents/g dust. A clear relationship was observed between a semi-quantitative interior score and the ERE-CALUX response of the samples. In addition, the concentration of phthalates, a major group of EEDCs used as plasticizers in plastics, was determined in the samples by GC-MS. Diisoheptyl phthalate (DiHP) and di(2-ethylhexyl) phthalate (DEHP) were present in every dust sample. A good correlation was found between ERE-CALUX activities and phthalate concentrations, when all phthalates except diisononyl phthalate (DiNP) and diisodecyl phthalate (DiDP), which do not bind to the estrogen receptor, were taken into account. This shows that the ERE-CALUX can provide relevant results concerning exposure to EEDCs from indoor dust. This article is part of a Special Issue entitled 'Endocrine disruptors & steroids'.
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Affiliation(s)
- T Vandermarken
- Vrije Universiteit Brussel, Department of Analytical, Environmental and Geo-Chemistry, Pleinlaan 2, 1050 Brussels, Belgium.
| | - S De Galan
- Vrije Universiteit Brussel, Department of Analytical, Environmental and Geo-Chemistry, Pleinlaan 2, 1050 Brussels, Belgium
| | - K Croes
- Vrije Universiteit Brussel, Department of Analytical, Environmental and Geo-Chemistry, Pleinlaan 2, 1050 Brussels, Belgium
| | - K Van Langenhove
- Vrije Universiteit Brussel, Department of Analytical, Environmental and Geo-Chemistry, Pleinlaan 2, 1050 Brussels, Belgium
| | - J Vercammen
- Interscience, Avenue J.E. Lenoir 2, 1348 Louvain-la-Neuve, Belgium
| | - H Sanctorum
- Vrije Universiteit Brussel, Department of Analytical, Environmental and Geo-Chemistry, Pleinlaan 2, 1050 Brussels, Belgium
| | - M S Denison
- Department of Environmental Toxicology, University of California at Davis, Davis, CA 95616, USA
| | - L Goeyens
- Vrije Universiteit Brussel, Department of Analytical, Environmental and Geo-Chemistry, Pleinlaan 2, 1050 Brussels, Belgium
| | - M Elskens
- Vrije Universiteit Brussel, Department of Analytical, Environmental and Geo-Chemistry, Pleinlaan 2, 1050 Brussels, Belgium
| | - W Baeyens
- Vrije Universiteit Brussel, Department of Analytical, Environmental and Geo-Chemistry, Pleinlaan 2, 1050 Brussels, Belgium
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Verbrugge FH, Nijst P, Van Herendael H, De Vusser P, Jacobs L, Vercammen J, Verhaert D, Vandervoort P, Dupont M, Mullens W, Rivero-Ayerza M. Asymptomatic episodes of device-registered atrial tachyarrhythmia are not associated with worse cardiac resynchronization therapy response. Europace 2014; 16:1197-204. [DOI: 10.1093/europace/eut434] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Claeys W, Baert K, Mestdagh F, Vercammen J, Daenens P, De Meulenaer B, Maghuin-Rogister G, Huyghebaert A. Assessment of the acrylamide intake of the Belgian population and the effect of mitigation strategies. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2010; 27:1199-207. [PMID: 20589545 DOI: 10.1080/19440049.2010.489577] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The acrylamide (AA) intake of the Belgian consumer was calculated based on AA monitoring data of the Belgian Federal Agency for the Safety of the Food Chain (FASFC) and consumption data of the Belgian food consumption survey coordinated by the Scientific Institute for Public Health (3214 participants of 15 years or older). The average AA exposure, calculated probabilistically, was 0.4 microg kg(-1) body weight (bw) day(-1) (P97.5 = 1.6 microg kg(-1) bw day(-1)), the main contributors to the average intake being chips (23%), coffee (19%), biscuits (13%), and bread (12%). Additionally, the impact of a number of AA mitigation scenarios was evaluated (German minimization concept, scenarios for mitigation from the literature, signal values), which is an important issue for public health as well as for policy-makers. Specific actions in cooperation with the food industry to reduce the AA content of foods seems to be a more efficient strategy than mere implementation of signal values. Considering that an important share of the AA intake is due to prepared meals, the catering industry as well as consumers need to be better informed on the various possibilities for keeping the AA content of meals as low as possible.
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Affiliation(s)
- W Claeys
- DG Control Policy, Federal Agency for the Safety of the Food Chain, Boulevard du Jardin botanique 55, Brussels, Belgium.
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Ho QT, Verboven P, Verlinden BE, Schenk A, Delele MA, Rolletschek H, Vercammen J, Nicolaï BM. Genotype effects on internal gas gradients in apple fruit. J Exp Bot 2010; 61:2745-55. [PMID: 20448049 DOI: 10.1093/jxb/erq108] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A permeation-diffusion-reaction model was applied to study gas exchange of apple fruit (Kanzi, Jonagold, and Braeburn) as effected by morphology and respiratory metabolism. The gas exchange properties and respiration parameters of the fruit organ tissues were measured. The actual internal tissue geometry of the fruit was reconstructed from digital fruit images and the model was solved over this geometry using the finite element method. The model was validated based on measurements of internal gas concentrations and the gas flux of the fruit to its environment. Both measurements and an in silico study revealed that gradients of metabolic gases exist in apple fruit, depending on diffusion properties and respiration of the different cultivars. Macroscale simulation confirmed that Jonagold has large potential for controlled atmosphere (CA) storage while low diffusion properties of cortex tissue in Braeburn indicated a risk of storage disorder development. Kanzi had less O(2) anoxia at CA storage compared with Braeburn.
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Affiliation(s)
- Q Tri Ho
- Flanders Centre of Postharvest Technology/BIOSYST-MeBioS, Faculty of Bioscience Engineering, Katholieke Universiteit Leuven, Willem de Croylaan 42, Leuven, Belgium
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9
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Hombrouck A, Hantson A, van Remoortel B, Michiels M, Vercammen J, Rhodes D, Tetz V, Engelborghs Y, Christ F, Debyser Z, Witvrouw M. Selection of human immunodeficiency virus type 1 resistance against the pyranodipyrimidine V-165 points to a multimodal mechanism of action. J Antimicrob Chemother 2007; 59:1084-95. [PMID: 17470918 DOI: 10.1093/jac/dkm101] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
OBJECTIVES We have previously identified the pyranodipyrimidines (PDPs) as a new class of integrase (IN) inhibitors. The most potent congener V-165 inhibits HIV-1 integration at low micromolar concentrations by inhibiting the binding of IN to the DNA. As part of pre-clinical studies with PDP, we wanted to investigate HIV resistance development against V-165 and to further characterize the physicochemical properties of the compound. METHODS We selected PDP-resistant HIV-1 strains by growing the virus in the presence of increasing concentrations of V-165. The selected strains were analysed genotypically and phenotypically. Mutant IN enzymes were generated and evaluated in an enzymatic oligonucleotide-based assay for their activity and sensitivity to the different IN inhibitors. In addition, the antiviral effect of the compound on viral entry and integration was measured using quantitative PCR. RESULTS Numerous mutations were detected in the RT, IN and env genes of the virus selected in the presence of V-165. Although V-165 inhibited integration in vivo as indicated by a decrease in the number of integrated proviruses, the compound also inhibited viral entry at a concentration of 19 microM. V-165 was poorly recovered from human hepatic microsomal matrix and 1% BSA. CONCLUSIONS These data point to a multimodal mechanism of action. A quest for derivatives of V-165 that specifically target IN should be pursued.
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Affiliation(s)
- A Hombrouck
- Laboratory for Molecular Virology and Drug Discovery, Katholieke Universiteit Leuven, Leuven, Flanders, Belgium
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Melese Endalew A, Hertog M, Delele MA, Baetens K, Vercammen J, Gomand A, Baelmans M, Ramon H, Nicolaï BM, Verboven P. 3D measurement and representation of pear canopy for modelling air-assisted orchard spraying. Commun Agric Appl Biol Sci 2007; 72:245-248. [PMID: 18018896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Affiliation(s)
- A Melese Endalew
- Faculty of Bioscience Engineering, BIOSYST - MeBioS, Katholieke Universiteit Leuven Willem de Croylaan 42, BE-3001 Leuven, Belgium
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11
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Geys J, Coenegrachts L, Vercammen J, Engelborghs Y, Nemmar A, Nemery B, Hoet PHM. In vitro study of the pulmonary translocation of nanoparticles: a preliminary study. Toxicol Lett 2005; 160:218-26. [PMID: 16137845 DOI: 10.1016/j.toxlet.2005.07.005] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2005] [Revised: 07/13/2005] [Accepted: 07/13/2005] [Indexed: 11/25/2022]
Abstract
Recent studies indicate that inhaled ultrafine particles can pass into the circulation. To study this translocation in an in vitro model three types of pulmonary epithelial cells were examined. The integrity of the cell monolayer was verified by measuring the transepithelial electrical resistance (TEER) and passage of sodium fluorescein. TEER was too low in A549 cells. In these preliminary experiments, TEER values of 1007+/-300 and 348+/-62 Omega cm2 were reached for the Calu-3 cell line, using permeable membranes of 0.4 and 3 microm pore size, respectively. Growing primary rat type II pneumocytes on 0.4 microm pores, a TEER value of 241+/-90 Omega cm2 was reached on day 5; on 3 microm pores, no acceptable high TEER value was obtained. Translocation studies were done using 46 nm fluorescent polystyrene particles. When incubating polystyrene particles on membranes without a cellular monolayer, significant translocation was only observed using 3 microm pores: 67.5% and 52.7% for carboxyl- and amine-modified particles, respectively. Only the Calu-3 cell line was used in an initial experiment to investigate the translocation: on 0.4 microm pores no translocation was observed, on 3 microm pores approximately 6% translocation was observed both for carboxyl- and amine-modified particles.
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Affiliation(s)
- J Geys
- Laboratory of Pneumology, Unit of Lung Toxicology, K.U. Leuven, Herestraat 49, Leuven 3000, Belgium
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12
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Witvrouw M, Fikkert V, Vercammen J, Maele B, Engelborghs Y, Debyser Z. Identification of Authentic Inhibitors of HIV-1 Integration. ACTA ACUST UNITED AC 2005. [DOI: 10.2174/1568012053507007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Abstract
Human immunodeficiency virus (HIV) is the etiological agent of the acquired immune deficiency syndrome (AIDS). The current strategy for the treatment of HIV infection is called Highly Active Antiretroviral Therapy (HAART) and is based on cocktails of drugs that are currently approved by the Food and Drug Administration. These drugs include compounds that target the viral entry step and the enzymes reverse transcriptase or protease. The introduction of HAART has dramatically changed the landscape of HIV disease. Death from AIDS-related diseases has been reduced significantly since HAART came into use. Nevertheless it is not clear how long clinical benefit will last taking into account the emergence of multiple drug-resistant viral strains. Addition of new anti-HIV drugs targeting other steps of the viral replication cycle may increase the potency of inhibition and delay resistance development. HIV integrase is an essential enzyme in the HIV life cycle and is an attractive target for new drug development. Despite years of intensive research, only two classes of compounds that inhibit integration have been identified until now, namely the diketo acids and the pyranodipyrimidines. In this review we will point to new potential antiviral targets related to retroviral integration that are amenable to drug development. We will describe the pitfalls of currently used integrase assays and propose new strategies and technologies for the discovery of HIV integration inhibitors. Furthermore, we will describe the two classes of integrase inhibitors and discuss their antiviral activity, molecular mechanism of anti-HIV action and the selection of HIV resistance against these drugs.
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Affiliation(s)
- M Witvrouw
- Rega Institute for Medical Research, Minderbroedersstraat 10, B-3000 Leuven, Flanders, Belgium
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Poelmans S, De Wasch K, De Brabander H, Van De Wiele M, Courtheyn D, van Ginkel L, Sterk S, Delahaut P, Dubois M, Schilt R, Nielen M, Vercammen J, Impens S, Stephany R, Hamoir T, Pottie G, Van Poucke C, Van Peteghem C. Analytical possibilities for the detection of stanozolol and its metabolites. Anal Chim Acta 2002. [DOI: 10.1016/s0003-2670(02)00672-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Courtheyn D, Le Bizec B, Brambilla G, De Brabander H, Cobbaert E, Van de Wiele M, Vercammen J, De Wasch K. Recent developments in the use and abuse of growth promoters. Anal Chim Acta 2002. [DOI: 10.1016/s0003-2670(02)00753-5] [Citation(s) in RCA: 182] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Abstract
An automated system for continuous on-line monitoring of biogenic emissions is presented. The system is designed in such a way that volatiles, emitted as reaction to biotic or abiotic stress, can be unequivocally elucidated. Two identical sampling units, named target and reference bulb, are therefore incorporated into the system and consecutively analyzed in monitoring experiments. A number of precautions were considered during these experiments to avoid the application of unwanted stress onto both organisms. Firstly, the system is constructed in such a way that both bulbs are continuously flushed, i.e. before, during and after analysis, with high purity air to avoid any accumulation of emitted volatiles. Moreover, the air is pre-humidified by bubbling it through water to sustain the biological samples for longer periods in the in vitro environment. Sorptive enrichment on polydimethylsiloxane (PDMS) was used to trap the headspace volatiles. The hydrophobic nature of this material permitted easy removal of trapped moisture by direct flushing of the sampling cartridge with dry air before desorption. The system was used to monitor the emissions from in vitro mechanically wounded ivy (Hedera helix) and of in vitro grown tomato plants (Lycopersicon esculentum Mill.) upon cotton leafworm (Spodoptera littoralis) feeding. Differences in light and dark floral emissions of jasmine (Jasminum polyanthum) were also studied.
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Affiliation(s)
- J Vercammen
- Department of Organic Chemistry, Ghent University, Belgium
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17
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Sandra P, Tienpont B, Vercammen J, Tredoux A, Sandra T, David F. Stir bar sorptive extraction applied to the determination of dicarboximide fungicides in wine. J Chromatogr A 2001; 928:117-26. [PMID: 11589467 DOI: 10.1016/s0021-9673(01)01113-x] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The dicarboximide fungicides vinclozolin, iprodione and procymidone were analyzed in white wines using stir bar sorptive extraction (SBSE) in combination with thermal desorption-capillary GC-MS analysis (TD-cGC-MS). The method was optimized using spiked water samples in a concentration range between 0.5 and 100 microg/l. Iprodione was measured as its degradation product 3,5-dichlorophenyl hydantoin. Limits of quantification in the full scan MS mode are 0.5 microg/l for vinclozolin and procymidone and 5 microg/l for iprodione. In the ion monitoring mode, concentrations 100 times lower can be dosed. Because of wine matrix effects on the recoveries, quantification of the target fungicides in wine had to be carried out by standard addition. For the thermolabile iprodione, the accuracy of SBSE-TD-cGC-MS was verified using SBSE followed by liquid desorption and analysis by liquid chromatography-atmospheric pressure chemical ionization mass spectroscopy. Procymidone and iprodione were detected in wines in concentrations up to 65 microg/l while the highest concentration of vinclozolin detected was smaller than 3 microg/l.
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Affiliation(s)
- P Sandra
- Department of Organic Chemistry, University of Gent, Ghent, Belgium.
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18
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De Wasch K, De Brabander HF, Van de Wiele M, Vercammen J, Courtheyn D, Impens S. Differentiation between dexamethasone and betamethasone in a mixture using multiple mass spectrometry. J Chromatogr A 2001; 926:79-86. [PMID: 11554421 DOI: 10.1016/s0021-9673(01)00744-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The objective of this study was to provide LC and GC-multiple mass spectrometry (MSn) data in positive and negative ion modes to prove the distinction between dexamethasone and betamethasone in a mixture of both components. Using GC-MS, the differentiation was based on a difference in the ratio of the ion traces of the two chromatographic peaks of the alpha and beta epimer with m/z 310 and 330. A minimum of 15% dexamethasone should be present in a mixture of both to detect it as present with a probability of 95%. In the same way betamethasone can be detected from 15% on. Because of the very similar structures of the dexamethasone and betamethasone epimers, no reversed-phase (RP) separations have been reported. Normal-phase separations have been reported in other studies. However because of the compatibility of RP mobile phases in the coupling with MS, the latter was the method of choice. In LC-MSn positive ion mode the product ion 355 was plotted against the sum of 337 and 319. With this combination dexamethasone and betamethasone could be discriminated in a mixture of 20 to 80% of each combination of analytes. In negative ion mode only two product ions were formed from the fragmentation of the acetate adduct, [M-H]- and [M-H-CH2O]-. The intensity of the fragment 391 ([M-H]-) was determined in the discrimination of the two epimers.
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Affiliation(s)
- K De Wasch
- Faculty of Veterinary Medicine of the University of Ghent, Department of Veterinary Food Inspection, Merelbeke, Belgium.
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19
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Van Gysel WD, Vercammen J, Debruyne F. Voice similarity in identical twins. Acta Otorhinolaryngol Belg 2001; 55:49-55. [PMID: 11256192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
If people are asked to discriminate visually the two individuals of a monozygotic twin (MT), they mostly get into trouble. Does this problem also exist when listening to twin voices? Twenty female and 10 male MT voices were randomly assembled with one "strange" voice to get voice trios. The listeners (10 female students in Speech and Language Pathology) were asked to label the twins (voices 1-2, 1-3 or 2-3) in two conditions: two standard sentences read aloud and a 2.5-second midsection of a sustained /a/. The proportion correctly labelled twins was for female voices 82% and 63% and for male voices 74% and 52% for the sentences and the sustained /a/ respectively, both being significantly greater than chance (33%). The acoustic analysis revealed a high intra-twin correlation for the speaking fundamental frequency (SFF) of the sentences and the fundamental frequency (F0) of the sustained /a/. So the voice pitch could have been a useful characteristic in the perceptual identification of the twins. We conclude that there is a greater perceptual resemblance between the voices of identical twins than between voices without genetic relationship. The identification however is not perfect. The voice pitch possibly contributes to the correct twin identifications.
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Affiliation(s)
- W D Van Gysel
- Department of ENT, Head and Neck Surgery, U.Z. St. Rafaël, Kapucijnenvoer 33, B-3000 Leuven
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Benijts T, Vercammen J, Dams R, Tuan HP, Lambert W, Sandra P. Stir bar sorptive extraction-thermal desorption-capillary gas chromatography-mass spectrometry applied to the analysis of polychlorinated biphenyls in human sperm. J Chromatogr B Biomed Sci Appl 2001; 755:137-42. [PMID: 11393697 DOI: 10.1016/s0378-4347(01)00048-2] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Stir bar sorptive extraction (SBSE) on polydimethylsiloxane (PDMS) was applied to the enrichment of polychlorinated biphenyls (PCBs) from human sperm. The seven Ballschmiter PCBs were used as model compounds. The extracted PCBs were then thermally desorbed from the stir bar and analysed on-line by capillary gas chromatography (CGC) with mass spectrometric detection (MS). Method development started with the analysis of PCBs spiked in water. Methanol had to be added to the samples in order to reduce the influence of glass adsorption on recovery and reproducibility. Recoveries in water for all PCBs varied around 50-60% and were limited for low molecular mass (MM) PCBs by polarity changes in the sample due to methanol addition and for high MM PCBs by non-equilibrium conditions. Matrix suppression by the lipophilic medium lowered the recoveries in the sperm samples proportional with PCB polarity. The method was validated and although limits of detection (LOD) for the individual congeners were in the sub-ppt level (<pg/ml), the limit of quantification (LOQ) was set at 10 ppt (10 pg/ml).
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Affiliation(s)
- T Benijts
- Laboratory of Toxicology, Ghent University, Belgium
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21
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Maes K, Vercammen J, Pham-Tuan H, Sandra P, Debergh PC. Critical aspects for the reliable headspace analysis of plants cultivated in vitro. Phytochem Anal 2001; 12:153-158. [PMID: 11705019 DOI: 10.1002/pca.579] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Various factors controlling the recoveries of volatile organic compounds in vitro headspace analysis of tomato plants (Lycopersicon esculentum Mill. 'Moneymaker'), sampled using solid phase micro-extraction, were evaluated and optimised. The variations in composition of the headspaces were determined as a function of time, and following in vitro wounding of the plant.
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Affiliation(s)
- K Maes
- Department of Plant Production-Horticulture, Ghent University, Coupure links 653, B-9000 Ghent, Belgium.
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22
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Vercammen J, Pham-Tuan H, Arickx I, Van der Straeten D, Sandra P. Monitoring of isothiocyanates emanating from Arabidopsis thaliana upon paraquat spraying. J Chromatogr A 2001; 912:127-34. [PMID: 11307975 DOI: 10.1016/s0021-9673(01)00558-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Arabidopsis thaliana plants were sprayed with the superoxide-generating herbicide paraquat. The headspace of sprayed plants was characterized by a number of compounds, which were absent in the headspace of untreated plants. They were identified as isothiocyanates (ITCs) with 4-methylthiobutyl isothiocyanate as main compound. After identification, a GC-system, based on PDMS sorption, was used to continuously monitor the ITC emissions. The specificity of isothiocyanate emission was also determined by subjecting the Arabidopsis thaliana plants to in vitro mechanical wounding. Again, 4-methylthiobutyl isothiocyanate was the main component, but the emission profile was completely different since the compound was emitted immediately, i.e., during wounding itself.
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Affiliation(s)
- J Vercammen
- Department of Organic Chemistry, Ghent University, Gent, Belgium
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23
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Van Craenenbroeck E, Vercammen J, Matthys G, Beirlant J, Marot C, Hoebeke J, Strobbe R, Engelborghs Y. Heuristic Statistical Analysis of Fluorescence Fluctuation Data with Bright Spikes: Application to Ligand Binding to the Human Serotonin Receptor Expressed in Escherichia coli Cells. Biol Chem 2001; 382:355-61. [PMID: 11347881 DOI: 10.1515/bc.2001.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractA statistical method for the analysis of fluorescence fluctuation amplitudes including bright spikes is presented. This situation arises e. g. when fluorescent ligands interact with receptors carrying multiple binding sites. The technique gives information on the amount of bound ligand in solution, making it a complementary technique to fluorescence correlation spectroscopy analysis, which cannot be applied in this situation. Two simple statistical tests are proposed that can discriminate between fluorescence intensities originating from free ligands or complexes. The performance of the two tests is evaluated and compared on mixtures of a fluorophore and fluorophore coated beads that mimic the behaviour of multiliganded complexes. An application to ligand binding to the serotonin receptor, expressed on Escherichia coli cells, is also provided. Specific binding of a fluorophore to this receptor, as well as competition with several ligands, is assessed.
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Affiliation(s)
- E Van Craenenbroeck
- Laboratory of Biomolecular Dynamics, Katholieke Universiteit Leuven, Belgium
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24
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Van De Wiele M, De Wasch K, Vercammen J, Courtheyn D, De Brabander H, Impens S. Determination of 16beta-hydroxystanozolol in urine and faeces by liquid chromatography-multiple mass spectrometry. J Chromatogr A 2000; 904:203-9. [PMID: 11204235 DOI: 10.1016/s0021-9673(00)00945-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This paper describes the optimisation of the detection of stanozolol and its major metabolite 16beta-hydroxystanozolol in faeces and urine from cattle. Faeces are extracted directly with diisopropyl ether. Urine is first submitted to an enzymatic hydrolysis and then extracted over a modified diatomaceous earth column (Chem-Elut) with a mixture of diisopropyl ether-isooctane. In a final step an acidic back extraction is performed. For the LC-MS-MS detection two approaches are discussed. In a first approach the final extract is detected without derivatization, while the second approach makes use of a derivatization step for 16beta-hydroxystanozolol. While the MS-MS spectrum without derivatization exhibits extensive fragmentation, the spectrum of the derivative shows two abundant diagnostic ions with much more reproducible ion ratios. The derivatization method and the method without derivatization enable the detection of 16beta-hydroxystanozolol up to 0.03 microg l(-1) in urine and 0.07 microg kg(-1) in faeces. Until now there is no literature available for the detection of 16beta-hydroxystanozolol in faeces and urine at the ppt level.
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Abstract
An automated capillary gas chromatographic system to measure ethylene emitted from biological materials is presented. The system consists of an on-line sampling device, a thermodesorption preconcentration apparatus and a capillary gas chromatograph with a flame ionization detection system. The limit of detection achievable on the GC system alone is 5 pg ethylene. The use of the strong Carboxen 1000 adsorbent at a sampling temperature as low as -50 degrees C allows sampling of volumes up to a few liters. Ethylene concentrations at low ppt levels can be accurately and reproducibly determined.
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Affiliation(s)
- H Pham-Tuan
- Department of Organic Chemistry, University of Ghent, Belgium
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26
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Courtheyn D, Vercammen J, Logghe M, Seghers H, De Wasch K, De Brabander H. Determination of betamethasone and triamcinolone acetonide by GC-NCI-MS in excreta of treated animals and development of a fast oxidation procedure for derivatisation of corticosteroids. Analyst 1998; 123:2409-14. [PMID: 10435270 DOI: 10.1039/a804921a] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The use of corticosteroids in combination with other hormonal substances has long been known to result in increased mass gain with bovines. Practice has demonstrated, however, that even the single use of a glucocorticoid may result in growth promoting effects. In addition to the popular dexamethasone, more recently other corticosteroids have also been misused for fattening purposes. The first part of this study deals with the detection of two of them, namely betamethasone and triamcinolone acetonide. Betamethasone was administered orally to a cow at a dose of 50 mg d-1 for 5 d, then later the same cow was injected intramuscularly with a dose of 50 mg of betamethasone dipropionate. Excretion in urine and faeces was followed with both HPLC-enzyme immunoassay and a previously described method based on negative chemical ionization mass spectrometry (NCI-MS) after oxidation. For the triamcinolone acetonide study a cow was treated with 50 mg d-1 of the drug during a 7 d period. Excretion in faeces was followed with GC-NCI-MS. As triamcinolone acetonide is resistant to the previously described oxidation procedure, however, a hydrolysis step had to be introduced prior to oxidation. In addition to this specific modification necessary for triamcinolone acetonide, in a subsequent part of this study the original oxidation procedure with pyridinium chlorochromate was re-investigated especially to shorten the procedure. With the introduction of potassium dichromate the reaction time could be decreased from 3 h to 10 min.
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De Brabander HF, De Wasch K, van Ginkel LA, Sterk SS, Blokland MH, Delahaut P, Taillieu X, Dubois M, Arts CJ, van Baak MJ, Gramberg LG, Schilt R, van Bennekom EO, Courtheyn D, Vercammen J, Witkamp RF. Multi-laboratory study of the analysis and kinetics of stanozolol and its metabolites in treated calves. Analyst 1998; 123:2599-604. [PMID: 10435307 DOI: 10.1039/a805110k] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The European Union banned the use of anabolic steroids for cattle fattening in 1988. Analytical techniques able to detect trace amounts of the parent drugs and their metabolites are mandatory for the control of abuse. Stanozolol (Stan) is an anabolic steroid that is often found in injection sites and cocktails. However, it has never been detected in tissues (kidney fat, meat) or excreta (urine, faeces) taken during regulatory inspection. The difference between the structure of Stan and the other steroids (a pyrazole ring fused to the androstane ring system) is probably the cause of this phenomenon. In the multi-laboratory study described here, veal calves were treated with intramuscular doses of Stan. In the excreta of these calves the presence, absence and/or concentration of Stan and of its major metabolites 16 beta-hydroxystanozolol and 3'-hydroxystanozolol were determined. For the determination of these analytes the different laboratories used different extraction and clean-up procedures and also evaluated different analytical techniques such as GC-MS (negative chemical ionization) and LC-MS-MS. The aim of this investigation was to explore which analyte should be validated for veterinary inspection purposes.
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Affiliation(s)
- H F De Brabander
- RUG, Faculty of Veterinary Medicine, Department of Veterinary Food Inspection, Merelbeke, Belgium.
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De Witte K, Vercammen J, van Daele G, Keulemans J. FRUIT SET, SEED SET AND FRUIT WEIGHT IN APPLE AS INFLUENCED BY EMASCULATION, SELF-POLLINATION AND CROSS-POLLINATION. ACTA ACUST UNITED AC 1996. [DOI: 10.17660/actahortic.1996.423.23] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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29
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De Brabander HF, Batjoens P, Courtheyn D, Vercammen J, De Wasch K. Comparison of the possibilities of gas chromatography-mass spectrometry and tandem mass spectrometry systems for the analysis of anabolics in biological material. J Chromatogr A 1996; 750:105-14. [PMID: 8938384 DOI: 10.1016/0021-9673(96)00411-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Chromatographic techniques such as GC-MS play a most important role in modern multi-residue analysis of anabolic steroids. The major difference between GC-MS apparatus from different manufacturers is the way of detection and recording. Most apparatus use selected-ion monitoring (SIM) for the determination of low concentrations. Systems based on ion trap technology record in full-scan to even picogram concentrations using a computer algorithm to compare the most important peaks of the mass spectrum of the unknown to those of the standard. In this investigation the possibilities of ion trap GC-MS and the recently released GCQ MS and MS2 for the analysis of anabolics in biological material are compared.
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Affiliation(s)
- H F De Brabander
- Department of Veterinary Food Inspection, Faculty of Veterinary Medicine, University of Ghent, Merelbeke, Belgium
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30
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Batjoens P, Courtheyn D, De Brabander HF, Vercammen J, De Wasch K, Logghe M. Gas chromatographic-tandem mass spectrometric analysis of clenbuterol residues in faeces. J Chromatogr A 1996; 750:133-9. [PMID: 8938386 DOI: 10.1016/0021-9673(96)00465-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In all EU member states, the use in livestock farming of certain substances having a hormonal action is prohibited. Clenbuterol, the beta-adrenergic agonist, has some growth promoting characteristics. Screening for clenbuterol can be carried out by an immunoassay. Gas chromatography-mass spectrometry (GC-MS) is very valuable for confirmatory purposes. In full scan MS it is impossible to fulfil the EU criteria of four diagnostic ions with one single ionisation mode. Some alternative possibilities are: (1) the use of two different ionisation modes, (2) the use of different derivatization methods or (3) the use of tandem MS. Each derivatisation or ionisation mode on its own did not give a sufficient number of ions. By combining these different possibilities we were able to obtain four ions, fulfilling the EU criteria.
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Affiliation(s)
- P Batjoens
- Department of Veterinary Food Inspection, Faculty of Veterinary Medicine, University of Ghent, Merelbeke, Belgium
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31
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Courtheyn D, Vercammen J, De Brabander H, Vandenreyt I, Batjoens P, Vanoosthuyze K, Van Peteghem C. Determination of dexamethasone in urine and faeces of treated cattle with negative chemical ionization-mass spectrometry. Analyst 1994; 119:2557-64. [PMID: 7879854 DOI: 10.1039/an9941902557] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
For several years, the misuse of dexamethasone and its esters in livestock production has been clearly demonstrated. The first part of the present study deals with the elaboration of a sensitive and specific method for the determination of residues of dexamethasone in excreta at the ppb level. Sample preparation for urine and faeces, including high-performance liquid chromatography (HPLC) fractionation, was carried out. The detection was based on established methodology employing negative chemical ionization-mass spectrometry (NCI-MS) after oxidation of the dexamethasone. In comparison with previous literature, the yield of oxidized dexamethasone was substantially improved and the oxidation procedure was made more simple and robust. In the second part of the study, the relationship between the dose of dexamethasone administered and the levels of the drug in excreta was investigated using this method, as was the ratio between drug levels in urine and faeces. Treatment was carried out for 7 d with an oral dose of 50 mg d-1, the maximum levels found in urine and faeces were 980 and 744 ppb, respectively. While the elimination via faeces responded much slower at the start and the end of treatment, the final part of both excretion profiles were very similar and a level of 1 ppb was reached in both matrices 9 d after the end of treatment. Gas chromatography-mass spectrometry (GC-MS) results obtained for the urine samples were compared with those obtained with direct enzyme immunoassay.
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32
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Vanoosthuyze K, Van Peteghem C, Courtheyn D, Vercammen J. Use of an immunomagnetic separation‐ELISA technique for the fast detection of growth promoters in cattle urine. FOOD AGR IMMUNOL 1994. [DOI: 10.1080/09540109409354835] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Duprez DA, De Buyzere M, De Sutter J, Vercammen J, Clement DL. Skin capillary erythrocyte velocity and mean 24 hour ambulatory blood pressure level. Int J Microcirc Clin Exp 1993; 12:193-8. [PMID: 8500978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This study aimed to examine the relation between capillary dynamics and parameters of ambulatory blood pressure (BP) recordings in a range covering very low to high BP (mean arterial BP: 70-140 mm Hg). A total number of 45 subjects underwent a 24 h ambulatory BP recording at 30 min intervals. The subjects did not receive any medication. Then the subjects were subdivided in 5 categories along their mean 24 h arterial BP values < 80, 80-90, 91-105, 106-115, > 115 mm Hg. Nailfold capillaries were examined at the level of the fourth finger using TV-microscopy. Our results demonstrate that erythrocyte velocity could be maintained relatively constant (mean velocities 700-800 microns/s) within the ambulatory mean arterial blood pressure range of 80-115 mm Hg. For very low and high blood pressures significant decreases (p < 0.01) were noted. Using office mean arterial blood pressure comparable results were obtained.
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Affiliation(s)
- D A Duprez
- Department of Cardiology and Angiology, University Hospital, Gent, Belgium
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Abstract
OBJECTIVE The aim of this study was to correlate capillary morphology and erythrocyte velocity to blood pressure in mild-to-moderate essential arterial hypertension. DESIGN Ambulatory blood pressure measurement may provide more precise information about a patient's mean blood pressure than office measurements. METHODS Fifteen patients with recently diagnosed, previously untreated mild-to-moderate essential hypertension underwent 24-h ambulatory blood pressure recording and a capillaroscopic examination of finger microcirculation. Erythrocyte velocity was determined by the flying spot technique. RESULTS Both mean 24-h ambulatory systolic blood pressure (SBP) and mean 24-h ambulatory diastolic blood pressure (DBP) were significantly inversely correlated with capillary erythrocyte velocity. However, the correlation between erythrocyte velocity and office SBP and office DBP was less significant. Capillary length was related to 24-h ambulatory DBP but not to office DBP. Capillary number was not related to any blood pressure parameter. CONCLUSIONS These results indicate that, in patients with mild-to-moderate essential hypertension, erythrocyte velocity is significantly lower than for matched controls. It is also inversely related to mean 24-h ambulatory SBP and 24-h ambulatory DBP.
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Affiliation(s)
- D Duprez
- Department of Cardiology and Angiology, University Hospital, Gent, Belgium
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35
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Duprez D, De Buyzere M, De Backer T, Vercammen J, Brusselmans F, Clement DL. Impaired microcirculation in moderate essential hypertension. J Hypertens Suppl 1991; 9:S128-9. [PMID: 1818910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- D Duprez
- Department of Cardiology and Angiology, University Hospital, Gent, Belgium
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36
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Duprez D, De Buyzere M, De Backer T, Vercammen J, Kaufman JM, Van Hoecke M, Vermeulen A, Clement D. Influence of nonhemodynamic factors on the microcirculation in moderate arterial essential hypertension. Am J Hypertens 1991; 4:885-9. [PMID: 1789951 DOI: 10.1093/ajh/4.11.885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
This study is aimed at examining the role of non-hemodynamic factors on the impaired microcirculation in patients with moderate essential hypertension. In a series of 31 patients (mean age, 47.8 +/- 1.1 years) with newly diagnosed untreated moderate essential hypertension (mean systolic blood pressure 161.7 +/- 2.0 mm Hg, mean diastolic blood pressure 102.4 +/- 1.5 mm Hg), parameters of the capillaroscopic examination of the finger microcirculation (mean number of capillaries, NRCAP), length of the capillaries (LECAP, microns), diameter micron) of the efferent (EFDI) and afferent (AFDI) apillaries, and mean red blood cell velocity (RBCV, microns/sec), which was measured by the flying spot technique, were correlated with a number of hormones (sampled after an overnight fast) including: plasma renin activity, aldosterone, and parathyroid hormone (PTH). A significant correlation (P less than .05) could be obtained between several parameters of the microcirculation and PTH:PTH (23.8 +/- 1.4 pg/mL)-NRCAP (14.9 +/- 0.5): r = -0.440, P = .013; PTH-AFDI (4.0 +/- 0.5 microns): r = 0.442, P = .012; PTH-EFDI (2.8 +/- 0.5 microns): r = 0.416, P = .019; PTH-RBCV (711 +/- 69 microns/sec): r = -0.351, P = .05. Furthermore, 24-h urinary norepinephrine (U-NOR) and afferent and efferent diameter of the capillaries intercorrelated significantly: U-NOR (46.0 +/- 6.2 micrograms/24 h)-AFDI: r = 0.439, P = .034; U-NOR-EFDI; r = 0.462, P = .025. This study shows that in patients with moderate essential arterial hypertension nonhemodynamic factors have an influence at the level of the microcirculation.
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Affiliation(s)
- D Duprez
- Department of Cardiology-Angiology, University Hospital, Gent, Belgium
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37
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Vermoesen A, Vercammen J, Sanders C, Courtheyn D, De Brabander HF. Comparison of two mass-selective detectors with special reference to the analysis of residues of anabolics. J Chromatogr 1991; 564:385-91. [PMID: 1874843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In the analysis of residues of anabolic agents the use of combined techniques, especially gas chromatography-mass spectrometry, is of increasing interest. When this method is used for the analysis of residues of anabolics it is very important to have a knowledge of the characteristics of the different types of apparatus on the market and to be sure that the results are not "apparatus-dependent". In this study two mass-selective detectors, the Hewlett-Packard 5970 and the ion trap detector 800, were compared by injecting the same samples of derivatized anabolics (standard solutions) into the two systems.
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Affiliation(s)
- A Vermoesen
- Rijksontledingslaboratorium, Ghentbrugge, Belgium
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