The Experts below are selected from a list of 132360 Experts worldwide ranked by ideXlab platform
Herman Vromans - One of the best experts on this subject based on the ideXlab platform.
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Scale up of Semisolid Dosage Forms Manufacturing Based on Process Understanding: from Lab to Industrial Scale
AAPS PharmSciTech, 2018Co-Authors: A. J.p. Van Heugten, Herman VromansAbstract:The scale up of production processes is a major challenge in pharmaceutical industry. Using a quality by Design approach, upscaling can be based on the Design space, which can be assessed on a small scale. In a previous study, the critical process parameters were identified by a definitive Screening Design on cetomacrogol ointment. In the current study, this lab scale (0.5 kg) study was scaled up to industrial scale (2000 kg, filling 100g tubes at 75 tubes/min). A similar trend for the influence of filling temperature on ointment yield stress was found for lab and industrial scale production. Furthermore, a process window for ointment filling viscosities was established. It was shown that between 26 and 170 Pa.s ointment could be filled into tubes with a low weight variation (
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the influence of cetomacrogol ointment processing on structure a definitive Screening Design
European Journal of Pharmaceutical Sciences, 2017Co-Authors: A. J.p. Van Heugten, C. L. Braal, Herman Vromans, Marjan VersluijshelderAbstract:Batch-to-batch variability is a challenge for the industrial scale production of ointments. Therefore the current investigation focussed on identifying and understanding critical process parameters (CPPs) for cetomacrogol ointment. This was evaluated using a definitive Screening Design (DSD) approach in which fourteen batches were produced under predefined and controlled conditions using the following variables: addition of SiO2 nanoparticles, mixing speed, cooling rate, heating temperature, container filling temperature and isothermal mixing at the filling temperature. Ointment structure was evaluated using a number of rheological parameters. One of these parameters, yield stress was found to be strongly influenced by filling temperature and mixing speed (p=0.0065 and p=0.0013 respectively). Both significantly affect ointment structure and they also have a significant interaction (p<0.05). Understanding the ointment production process can help in defining a processing window to produce ointment of constant quality.
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The influence of cetomacrogol ointment processing on structure: A definitive Screening Design
European Journal of Pharmaceutical Sciences, 2017Co-Authors: A. J.p. Van Heugten, C. L. Braal, Marjan Versluijs-helder, Herman VromansAbstract:Batch-to-batch variability is a challenge for the industrial scale production of ointments. Therefore the current investigation focussed on identifying and understanding critical process parameters (CPPs) for cetomacrogol ointment. This was evaluated using a definitive Screening Design (DSD) approach in which fourteen batches were produced under predefined and controlled conditions using the following variables: addition of SiO2 nanoparticles, mixing speed, cooling rate, heating temperature, container filling temperature and isothermal mixing at the filling temperature. Ointment structure was evaluated using a number of rheological parameters. One of these parameters, yield stress was found to be strongly influenced by filling temperature and mixing speed (p = 0.0065 and p = 0.0013 respectively). Both significantly affect ointment structure and they also have a significant interaction (p
Richard T Scott - One of the best experts on this subject based on the ideXlab platform.
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single nucleotide polymorphism microarray based concurrent Screening of 24 chromosome aneuploidy and unbalanced translocations in preimplantation human embryos
Fertility and Sterility, 2011Co-Authors: Nathan R Treff, Brynn Levy, L E Northrop, Khushabu Kasabwala, Richard T ScottAbstract:Objective To develop, validate, and apply a single nucleotide polymorphism (SNP) microarray–based method for simultaneous preimplantation genetic diagnosis (PGD) of unbalanced inheritance of rearranged chromosomes and 24-chromosome aneuploidy Screening. Design Prospective clinical research study. Setting Academic reproductive medicine center. Patient(s) Eighteen couples carrying a balanced reciprocal or Robertsonian chromosomal rearrangement. Intervention(s) PGD on blastocyst trophectoderm biopsy specimens. Main Outcome Measure(s) Aneuploidy, implantation, pregnancy, and delivery rates after SNP microarray–based aneuploidy and translocation Screening. Result(s) Single nucleotide polymorphism microarray was capable of detecting translocation-associated imbalances as small as 9.0 megabases. In the 12 transfers performed, sustained implantation occurred for 9 (45%) of 20 balanced-normal and euploid embryos replaced. The clinical pregnancy rate in patients receiving a transfer was 75% with six singleton deliveries and three ongoing singleton pregnancies thus far. Significantly fewer embryos were eligible for transfer with the incorporation of simultaneous 24-chromosome aneuploidy Screening. Arrested embryos were also significantly more likely to possess unbalanced chromosomes when compared with developmentally competent blastocysts. Conclusion(s) This SNP microarray–based method provides the first opportunity to improve outcomes through comprehensive identification of euploid embryos from translocation carrier couples.
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accurate single cell 24 chromosome aneuploidy Screening using whole genome amplification and single nucleotide polymorphism microarrays
Fertility and Sterility, 2010Co-Authors: Nathan R Treff, Brynn Levy, X Tao, Richard T ScottAbstract:Objective To develop and validate a whole genome amplification and single nucleotide polymorphism (SNP) microarray protocol for accurate single cell 24 chromosome aneuploidy Screening. Design Prospective, randomized, and blinded study. Setting Academic reproductive medicine center. Patient(s) Multiple euploid and aneuploid cell lines were obtained from a public repository and blastomeres were obtained after biopsy of cleavage stage embryos from 78 patients undergoing IVF. Main Outcome Measure(s) Accuracy of copy number assignment and consistency of individual SNPs, whole chromosomes, and single cell aneuploidy status were determined. Intervention(s) None. Result(s) Single cells extracted from karyotypically defined cell lines provided 99.2% accuracy for individual SNPs, 99.8% accuracy for whole chromosomes, and 98.6% accuracy when applying a quality control threshold for the overall assignment of aneuploidy status. The concurrence for more than 80 million SNPs in 335 single blastomeres was 96.5%. Conclusion(s) We have established and validated a SNP microarray-based single cell aneuploidy Screening technology. Clinical validation studies are underway to determine the predictive value of this methodology.
Mathilde E Boon - One of the best experts on this subject based on the ideXlab platform.
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pobascam a population based randomized controlled trial for implementation of high risk hpv testing in cervical Screening Design methods and baseline data of 44 102 women
International Journal of Cancer, 2004Co-Authors: Nicole W J Bulkmans, Lawrence Rozendaal, Peter J F Snijders, Feja J Voorhorst, Joan A P Boeke, Gladys R J Zandwijken, Folkert J Van Kemenade, Rene H M Verheijen, Krijn V Groningen, Mathilde E BoonAbstract:Cytological cervical Screening is rather inefficient because of relatively high proportions of false negative and false positive smears. To evaluate the efficiency of high-risk human papillomavirus (hrHPV) testing, by GP5+/6+ PCR-enzyme immunoassay (EIA), in conjunction with cytology (Intervention Group) to that of the classical cytology (Control Group), we initiated the Population Based Screening Study Amsterdam (POBASCAM). POBASCAM is a population-based randomized controlled trial for implementation of hrHPV testing in cervical Screening. The outcome measure is the proportion of histologically confirmed > or =CIN3 lesions in each study arm up to and including the next Screening round after 5 years. We present the Design, methods and baseline data of POBASCAM. When, in the next 5 years, the follow-up will be completed, the data obtained will be used in model studies, including a cost-effectiveness study, to advise the Dutch Ministry of Public Health in deciding whether cervical Screening should be based on combined hrHPV and cytology testing instead of cytology alone. Between January 1999 and September 2002, 44,102 women (mean age = 42.8 years; range = 29-61) that participated in the regular Dutch Screening program were included in our study. In the Intervention Group the distribution of cytology and hrHPV by cytology class was as follows: normal cytology 96.6% (3.6% hrHPV positive); borderline and mild dyskaryosis (BMD) 2.5% (34.6% hrHPV positive); and moderate dyskaryosis or worse (>BMD) 0.8% (88.3% hrHPV positive), i.e., 0.4% moderate dyskaryosis (82.9% hrHPV positive), 0.3% severe dyskaryosis (92.5% hrHPV positive), 0.1% carcinoma in situ (95.2% hrHPV positive), BMD, i.e., 0.4% moderate dyskaryosis, 0.3% severe dyskaryosis, 0.1% carcinoma in situ, BMD of 13.7% among women with a positive hrHPV test was not age-dependent. Our study indicates that large-scale hrHPV testing by GP5+/6+ PCR-EIA in the setting of population-based cervical Screening is practically feasible, is accepted by both participating women and general practitioners and yields highly reproducible results.
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pobascam a population based randomized controlled trial for implementation of high risk hpv testing in cervical Screening Design methods and baseline data of 44 102 women
International Journal of Cancer, 2004Co-Authors: Nicole W J Bulkmans, Lawrence Rozendaal, Peter J F Snijders, Feja J Voorhorst, Joan A P Boeke, Gladys R J Zandwijken, Rene H M Verheijen, Krijn V Groningen, Folkert J Van Kemenade, Mathilde E BoonAbstract:Cytological cervical Screening is rather inefficient because of relatively high proportions of false negative and false positive smears. To evaluate the efficiency of high-risk human papillomavirus (hrHPV) testing, by GP5+/6+ PCR-enzyme immunoassay (EIA), in conjunction with cytology (Intervention Group) to that of the classical cytology (Control Group), we initiated the Population Based Screening Study Amsterdam (POBASCAM). POBASCAM is a population-based randomized controlled trial for implementation of hrHPV testing in cervical Screening. The outcome measure is the proportion of histologically confirmed ≥CIN3 lesions in each study arm up to and including the next Screening round after 5 years. We present the Design, methods and baseline data of POBASCAM. When, in the next 5 years, the follow-up will be completed, the data obtained will be used in model studies, including a cost-effectiveness study, to advise the Dutch Ministry of Public Health in deciding whether cervical Screening should be based on combined hrHPV and cytology testing instead of cytology alone. Between January 1999 and September 2002, 44,102 women (mean age = 42.8 years; range = 29–61) that participated in the regular Dutch Screening program were included in our study. In the Intervention Group the distribution of cytology and hrHPV by cytology class was as follows: normal cytology 96.6% (3.6% hrHPV positive); borderline and mild dyskaryosis (BMD) 2.5% (34.6% hrHPV positive); and moderate dyskaryosis or worse (>BMD) 0.8% (88.3% hrHPV positive), i.e., 0.4% moderate dyskaryosis (82.9% hrHPV positive), 0.3% severe dyskaryosis (92.5% hrHPV positive), 0.1% carcinoma in situ (95.2% hrHPV positive), BMD, i.e., 0.4% moderate dyskaryosis, 0.3% severe dyskaryosis, 0.1% carcinoma in situ, BMD of 13.7% among women with a positive hrHPV test was not age-dependent. Our study indicates that large-scale hrHPV testing by GP5+/6+ PCR-EIA in the setting of population-based cervical Screening is practically feasible, is accepted by both participating women and general practitioners and yields highly reproducible results. © 2004 Wiley-Liss, Inc.
Nathan R Treff - One of the best experts on this subject based on the ideXlab platform.
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single nucleotide polymorphism microarray based concurrent Screening of 24 chromosome aneuploidy and unbalanced translocations in preimplantation human embryos
Fertility and Sterility, 2011Co-Authors: Nathan R Treff, Brynn Levy, L E Northrop, Khushabu Kasabwala, Richard T ScottAbstract:Objective To develop, validate, and apply a single nucleotide polymorphism (SNP) microarray–based method for simultaneous preimplantation genetic diagnosis (PGD) of unbalanced inheritance of rearranged chromosomes and 24-chromosome aneuploidy Screening. Design Prospective clinical research study. Setting Academic reproductive medicine center. Patient(s) Eighteen couples carrying a balanced reciprocal or Robertsonian chromosomal rearrangement. Intervention(s) PGD on blastocyst trophectoderm biopsy specimens. Main Outcome Measure(s) Aneuploidy, implantation, pregnancy, and delivery rates after SNP microarray–based aneuploidy and translocation Screening. Result(s) Single nucleotide polymorphism microarray was capable of detecting translocation-associated imbalances as small as 9.0 megabases. In the 12 transfers performed, sustained implantation occurred for 9 (45%) of 20 balanced-normal and euploid embryos replaced. The clinical pregnancy rate in patients receiving a transfer was 75% with six singleton deliveries and three ongoing singleton pregnancies thus far. Significantly fewer embryos were eligible for transfer with the incorporation of simultaneous 24-chromosome aneuploidy Screening. Arrested embryos were also significantly more likely to possess unbalanced chromosomes when compared with developmentally competent blastocysts. Conclusion(s) This SNP microarray–based method provides the first opportunity to improve outcomes through comprehensive identification of euploid embryos from translocation carrier couples.
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accurate single cell 24 chromosome aneuploidy Screening using whole genome amplification and single nucleotide polymorphism microarrays
Fertility and Sterility, 2010Co-Authors: Nathan R Treff, Brynn Levy, X Tao, Richard T ScottAbstract:Objective To develop and validate a whole genome amplification and single nucleotide polymorphism (SNP) microarray protocol for accurate single cell 24 chromosome aneuploidy Screening. Design Prospective, randomized, and blinded study. Setting Academic reproductive medicine center. Patient(s) Multiple euploid and aneuploid cell lines were obtained from a public repository and blastomeres were obtained after biopsy of cleavage stage embryos from 78 patients undergoing IVF. Main Outcome Measure(s) Accuracy of copy number assignment and consistency of individual SNPs, whole chromosomes, and single cell aneuploidy status were determined. Intervention(s) None. Result(s) Single cells extracted from karyotypically defined cell lines provided 99.2% accuracy for individual SNPs, 99.8% accuracy for whole chromosomes, and 98.6% accuracy when applying a quality control threshold for the overall assignment of aneuploidy status. The concurrence for more than 80 million SNPs in 335 single blastomeres was 96.5%. Conclusion(s) We have established and validated a SNP microarray-based single cell aneuploidy Screening technology. Clinical validation studies are underway to determine the predictive value of this methodology.
A. J.p. Van Heugten - One of the best experts on this subject based on the ideXlab platform.
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Scale up of Semisolid Dosage Forms Manufacturing Based on Process Understanding: from Lab to Industrial Scale
AAPS PharmSciTech, 2018Co-Authors: A. J.p. Van Heugten, Herman VromansAbstract:The scale up of production processes is a major challenge in pharmaceutical industry. Using a quality by Design approach, upscaling can be based on the Design space, which can be assessed on a small scale. In a previous study, the critical process parameters were identified by a definitive Screening Design on cetomacrogol ointment. In the current study, this lab scale (0.5 kg) study was scaled up to industrial scale (2000 kg, filling 100g tubes at 75 tubes/min). A similar trend for the influence of filling temperature on ointment yield stress was found for lab and industrial scale production. Furthermore, a process window for ointment filling viscosities was established. It was shown that between 26 and 170 Pa.s ointment could be filled into tubes with a low weight variation (
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the influence of cetomacrogol ointment processing on structure a definitive Screening Design
European Journal of Pharmaceutical Sciences, 2017Co-Authors: A. J.p. Van Heugten, C. L. Braal, Herman Vromans, Marjan VersluijshelderAbstract:Batch-to-batch variability is a challenge for the industrial scale production of ointments. Therefore the current investigation focussed on identifying and understanding critical process parameters (CPPs) for cetomacrogol ointment. This was evaluated using a definitive Screening Design (DSD) approach in which fourteen batches were produced under predefined and controlled conditions using the following variables: addition of SiO2 nanoparticles, mixing speed, cooling rate, heating temperature, container filling temperature and isothermal mixing at the filling temperature. Ointment structure was evaluated using a number of rheological parameters. One of these parameters, yield stress was found to be strongly influenced by filling temperature and mixing speed (p=0.0065 and p=0.0013 respectively). Both significantly affect ointment structure and they also have a significant interaction (p<0.05). Understanding the ointment production process can help in defining a processing window to produce ointment of constant quality.
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The influence of cetomacrogol ointment processing on structure: A definitive Screening Design
European Journal of Pharmaceutical Sciences, 2017Co-Authors: A. J.p. Van Heugten, C. L. Braal, Marjan Versluijs-helder, Herman VromansAbstract:Batch-to-batch variability is a challenge for the industrial scale production of ointments. Therefore the current investigation focussed on identifying and understanding critical process parameters (CPPs) for cetomacrogol ointment. This was evaluated using a definitive Screening Design (DSD) approach in which fourteen batches were produced under predefined and controlled conditions using the following variables: addition of SiO2 nanoparticles, mixing speed, cooling rate, heating temperature, container filling temperature and isothermal mixing at the filling temperature. Ointment structure was evaluated using a number of rheological parameters. One of these parameters, yield stress was found to be strongly influenced by filling temperature and mixing speed (p = 0.0065 and p = 0.0013 respectively). Both significantly affect ointment structure and they also have a significant interaction (p
