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K H Nicolaides - One of the best experts on this subject based on the ideXlab platform.

  • first trimester screening for trisomies 21 18 and 13 by ultrasound and Biochemical Testing
    Fetal Diagnosis and Therapy, 2014
    Co-Authors: David Wright, Argyro Syngelaki, Ian Bradbury, Ranjit Akolekar, K H Nicolaides
    Abstract:

    cutoff of 1: 100, the estimated detection rate (DR) was 87.0% for trisomy 21 and 91.8% for trisomies 18 and 13, at a false- positive rate (FPR) of 2.2%. Addition of PLGF, AFP and DV PIV increased the DR to 93.3% for trisomy 21 and 95.4% for triso- mies 18 and 13 and reduced the FPR to 1.3%. Conclusions: Effective screening for trisomies can be achieved using spe- cific algorithms based on NT, FHR, DV PIV, β-hCG, PAPP-A, PLGF and AFP. Abstract Objective: To examine the performance of screening for tri- somies 21, 18 and 13 at 11-13 weeks' gestation using spe- cific algorithms for these trisomies based on combinations of fetal nuchal translucency thickness (NT), fetal heart rate (FHR), ductus venosus pulsatility index for veins (DV PIV), and serum free β-human chorionic gonadotropin (β-hCG), preg- nancy-associated plasma protein A (PAPP-A), placental growth factor (PLGF) and α-fetoprotein (AFP). Methods: Model-based estimates of screening performance were pro- duced for the distribution of maternal ages in England and Wales in 2011, and prospectively collected data on fetal NT, FHR, DV PIV, β-hCG, PAPP-A, PLGF and AFP from singleton pregnancies undergoing aneuploidy screening. Results: In screening by NT, FHR, free β-hCG and PAPP-A, using specific algorithms for trisomy 21 and trisomies 18 and 13 at the risk

  • two stage first trimester screening for trisomy 21 by ultrasound assessment and Biochemical Testing
    Ultrasound in Obstetrics & Gynecology, 2010
    Co-Authors: K O Kagan, I Staboulidou, Jader De Jesus Cruz, David Wright, K H Nicolaides
    Abstract:

    Objectives This study was carried out to examine the performance of a contingent policy in first-trimester screening for trisomy 21, in which the estimated risk was first derived by a combination of maternal age, fetal nuchal translucency (NT) thickness, presence/absence of the nasal bone, blood flow in the ductus venosus or flow across the tricuspid valve, and Biochemical Testing was carried out only in those who were found to have an intermediate risk. We also examined the performance of a policy in which the estimated risk was first derived by a combination of maternal age and Biochemical Testing, and ultrasound examination was carried out only in those with an intermediate risk. Methods The data for this study were derived from prospective screening for trisomy 21 in singleton pregnancies, using, as markers, a combination of maternal age, fetal NT thickness and maternal-serum free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein-A (PAPP-A), in a onestop clinic for first-trimester assessment of risk at 11 + 0 to 13 + 6 weeks of gestation. Assessment of the fetal nasal bone, ductus venosus flow and tricuspid flow were also routinely performed by appropriately trained sonographers. The performance of different screening policies was examined. Results The study population consisted of 19 614 pregnancies with a normal karyotype or delivery of a phenotypically normal baby (euploid group) and 122 cases of trisomy 21. The best performance was achieved by a contingent policy in which first-stage screening was based on maternal age, fetal NT thickness and either tricuspid valve or ductus venosus blood flow, followed by Biochemical Testing only those with an intermediate risk, of 1 in 51 to 1 in 1000 (which constituted about 20% of the total). The performance of contingent screening in which first-stage Testing relies on biochemistry was poorer than when first-stage screening was performed by ultrasound examination because, in order to achieve the same detection rate, the false-positive rate was twice as high. Conclusion Effective first-trimester screening for trisomy 21 can be achieved by a contingent policy in which first-stage Testing is based on ultrasound examination and second-stage Biochemical Testing is carried out in only 20% of the patients. Copyright  2010 ISUOG. Published by John Wiley & Sons, Ltd.

Matthew D. Collins - One of the best experts on this subject based on the ideXlab platform.

  • Actinomyces vaccimaxillae sp. nov., from the jaw of a cow.
    International Journal of Systematic and Evolutionary Microbiology, 2003
    Co-Authors: Val Hall, Matthew D. Collins, Roger A Hutson, Elisabeth Inganäs, Enevold Falsen, Brian I Duerden
    Abstract:

    A previously undescribed Actinomyces-like bacterium was isolated from a lesion in the jaw of a cow. Based on its cellular morphology and the results of Biochemical Testing, the organism was tentatively identified as a member of the genus Actinomyces. Comparative 16S rRNA gene sequencing studies showed that the bacterium represents a hitherto unknown species within the genus Actinomyces, and is related to a group of species that includes Actinomyces turicensis and its close relatives. It is proposed that the unknown organism be classified as Actinomyces vaccimaxillae sp. nov. (the type strain is CCUG 46091T=CIP 107423T).

  • Actinomyces oricola sp. nov., from a human dental abscess.
    International journal of systematic and evolutionary microbiology, 2003
    Co-Authors: Val Hall, Matthew D. Collins, Roger A Hutson, Elisabeth Inganäs, Enevold Falsen, Brian I Duerden
    Abstract:

    A previously undescribed Actinomyces-like bacterium was isolated from a human dental abscess. Based on its cellular morphology and the results of Biochemical Testing the organism was tentatively identified as a member of the genus Actinomyces, but it did not correspond to any currently recognized species of this genus. Comparative 16S rRNA gene sequencing studies showed the bacterium represents a hitherto unknown subline within the genus Actinomyces, clustering within a group of species, which includes Actinomyces bovis, the type species of the genus. Based on Biochemical and molecular phylogenetic evidence, it is proposed that the unknown organism recovered from a dental abscess be classified as a new species, Actinomyces oricola sp. nov. The type strain of Actinomyces oricola is R5292(T) (=CCUG 46090(T)=CIP 107639(T)).

  • Actinomyces coleocanis sp. nov., from the vagina of a dog.
    International Journal of Systematic and Evolutionary Microbiology, 2002
    Co-Authors: Lesley Hoyles, Geoffrey Foster, Enevold Falsen, Matthew D. Collins
    Abstract:

    A hitherto undescribed Actinomyces-like bacterium was isolated from the vagina of a dog. Biochemical Testing and PAGE analysis of whole-cell proteins indicated that the isolate was phenotypically different from previously described Actinomyces species and related taxa. Sequencing of 165 rRNA showed that the unknown bacterium was distinct from all currently known Actinomyces species. Phylogenetically, the unidentified organism displayed a specific association with Actinomyces europaeus, but a sequence divergence of > 5% demonstrated that it represents a distinct species. Based on both phenotypic and 165 rRNA sequence considerations, it is proposed that the unknown strain from a dog be classified as a novel species, Actinomyces coleocanis sp. nov. The type strain is CCUG 41708T (= CIP 106873T).

  • characterization of actinomyces isolates from infected root canals of teeth description of actinomyces radicidentis sp nov
    Journal of Clinical Microbiology, 2000
    Co-Authors: Matthew D. Collins, Lesley Hoyles, Natalia Nikolaitchouk, Sotos Kalfas, Goran Sundquist, Tor Monsen, Enevold Falsen
    Abstract:

    Two strains of a previously undescribed Actinomyces-like bacterium were recovered in pure culture from infected root canals of teeth. Analysis by Biochemical Testing and polyacrylamide gel electrophoresis of whole-cell proteins indicated that the strains closely resembled each other phenotypically but were distinct from previously described Actinomyces and Arcanobacterium species. Comparative 16S rRNA gene-sequencing studies showed the bacterium to be a hitherto unknown subline within a group of Actinomyces species which includes Actinomyces bovis, the type species of the genus. Based on phylogenetic and phenotypic evidence, we propose that the unknown bacterium isolated from human clinical specimens be classified as Actinomyces radicidentis sp. nov. The type strain of Actinomyces radicidentis is CCUG 36733.

  • Actinomyces canis sp. nov., isolated from dogs.
    International Journal of Systematic and Evolutionary Microbiology, 2000
    Co-Authors: Lesley Hoyles, Geoffrey Foster, Cristina Pascual, Christina Greko, Enevold Falsen, Matthew D. Collins
    Abstract:

    Three strains of a previously undescribed catalase-positive Actinomyces-like bacterium were isolated from dogs. Biochemical Testing and PAGE analysis of whole-cell proteins indicated that the strains were phenotypically highly related to each other but different from previously described Actinomyces and Arcanobacterium species. Sequencing of 16S rRNA showed that the unknown bacterium represents a new subline within a cluster of species which includes Actinomyces hyovaginalis, Actinomyces georgiae, Actinomyces meyeri, Actinomyces odontolyticus, Actinomyces radingae and Actinomyces turicensis. On the basis of phenotypic evidence and 16S rRNA sequence divergence levels (greater than 5% with recognized Actinomyces species) it is proposed that the unknown strains from canine sources be classified as a new species with the name Actinomyces canis sp. nov. The type strain of Actinomyces canis is CCUG 41706T (= CIP 106351T).

K O Kagan - One of the best experts on this subject based on the ideXlab platform.

  • two stage first trimester screening for trisomy 21 by ultrasound assessment and Biochemical Testing
    Ultrasound in Obstetrics & Gynecology, 2010
    Co-Authors: K O Kagan, I Staboulidou, Jader De Jesus Cruz, David Wright, K H Nicolaides
    Abstract:

    Objectives This study was carried out to examine the performance of a contingent policy in first-trimester screening for trisomy 21, in which the estimated risk was first derived by a combination of maternal age, fetal nuchal translucency (NT) thickness, presence/absence of the nasal bone, blood flow in the ductus venosus or flow across the tricuspid valve, and Biochemical Testing was carried out only in those who were found to have an intermediate risk. We also examined the performance of a policy in which the estimated risk was first derived by a combination of maternal age and Biochemical Testing, and ultrasound examination was carried out only in those with an intermediate risk. Methods The data for this study were derived from prospective screening for trisomy 21 in singleton pregnancies, using, as markers, a combination of maternal age, fetal NT thickness and maternal-serum free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein-A (PAPP-A), in a onestop clinic for first-trimester assessment of risk at 11 + 0 to 13 + 6 weeks of gestation. Assessment of the fetal nasal bone, ductus venosus flow and tricuspid flow were also routinely performed by appropriately trained sonographers. The performance of different screening policies was examined. Results The study population consisted of 19 614 pregnancies with a normal karyotype or delivery of a phenotypically normal baby (euploid group) and 122 cases of trisomy 21. The best performance was achieved by a contingent policy in which first-stage screening was based on maternal age, fetal NT thickness and either tricuspid valve or ductus venosus blood flow, followed by Biochemical Testing only those with an intermediate risk, of 1 in 51 to 1 in 1000 (which constituted about 20% of the total). The performance of contingent screening in which first-stage Testing relies on biochemistry was poorer than when first-stage screening was performed by ultrasound examination because, in order to achieve the same detection rate, the false-positive rate was twice as high. Conclusion Effective first-trimester screening for trisomy 21 can be achieved by a contingent policy in which first-stage Testing is based on ultrasound examination and second-stage Biochemical Testing is carried out in only 20% of the patients. Copyright  2010 ISUOG. Published by John Wiley & Sons, Ltd.

David Wright - One of the best experts on this subject based on the ideXlab platform.

  • first trimester screening for trisomies 21 18 and 13 by ultrasound and Biochemical Testing
    Fetal Diagnosis and Therapy, 2014
    Co-Authors: David Wright, Argyro Syngelaki, Ian Bradbury, Ranjit Akolekar, K H Nicolaides
    Abstract:

    cutoff of 1: 100, the estimated detection rate (DR) was 87.0% for trisomy 21 and 91.8% for trisomies 18 and 13, at a false- positive rate (FPR) of 2.2%. Addition of PLGF, AFP and DV PIV increased the DR to 93.3% for trisomy 21 and 95.4% for triso- mies 18 and 13 and reduced the FPR to 1.3%. Conclusions: Effective screening for trisomies can be achieved using spe- cific algorithms based on NT, FHR, DV PIV, β-hCG, PAPP-A, PLGF and AFP. Abstract Objective: To examine the performance of screening for tri- somies 21, 18 and 13 at 11-13 weeks' gestation using spe- cific algorithms for these trisomies based on combinations of fetal nuchal translucency thickness (NT), fetal heart rate (FHR), ductus venosus pulsatility index for veins (DV PIV), and serum free β-human chorionic gonadotropin (β-hCG), preg- nancy-associated plasma protein A (PAPP-A), placental growth factor (PLGF) and α-fetoprotein (AFP). Methods: Model-based estimates of screening performance were pro- duced for the distribution of maternal ages in England and Wales in 2011, and prospectively collected data on fetal NT, FHR, DV PIV, β-hCG, PAPP-A, PLGF and AFP from singleton pregnancies undergoing aneuploidy screening. Results: In screening by NT, FHR, free β-hCG and PAPP-A, using specific algorithms for trisomy 21 and trisomies 18 and 13 at the risk

  • two stage first trimester screening for trisomy 21 by ultrasound assessment and Biochemical Testing
    Ultrasound in Obstetrics & Gynecology, 2010
    Co-Authors: K O Kagan, I Staboulidou, Jader De Jesus Cruz, David Wright, K H Nicolaides
    Abstract:

    Objectives This study was carried out to examine the performance of a contingent policy in first-trimester screening for trisomy 21, in which the estimated risk was first derived by a combination of maternal age, fetal nuchal translucency (NT) thickness, presence/absence of the nasal bone, blood flow in the ductus venosus or flow across the tricuspid valve, and Biochemical Testing was carried out only in those who were found to have an intermediate risk. We also examined the performance of a policy in which the estimated risk was first derived by a combination of maternal age and Biochemical Testing, and ultrasound examination was carried out only in those with an intermediate risk. Methods The data for this study were derived from prospective screening for trisomy 21 in singleton pregnancies, using, as markers, a combination of maternal age, fetal NT thickness and maternal-serum free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein-A (PAPP-A), in a onestop clinic for first-trimester assessment of risk at 11 + 0 to 13 + 6 weeks of gestation. Assessment of the fetal nasal bone, ductus venosus flow and tricuspid flow were also routinely performed by appropriately trained sonographers. The performance of different screening policies was examined. Results The study population consisted of 19 614 pregnancies with a normal karyotype or delivery of a phenotypically normal baby (euploid group) and 122 cases of trisomy 21. The best performance was achieved by a contingent policy in which first-stage screening was based on maternal age, fetal NT thickness and either tricuspid valve or ductus venosus blood flow, followed by Biochemical Testing only those with an intermediate risk, of 1 in 51 to 1 in 1000 (which constituted about 20% of the total). The performance of contingent screening in which first-stage Testing relies on biochemistry was poorer than when first-stage screening was performed by ultrasound examination because, in order to achieve the same detection rate, the false-positive rate was twice as high. Conclusion Effective first-trimester screening for trisomy 21 can be achieved by a contingent policy in which first-stage Testing is based on ultrasound examination and second-stage Biochemical Testing is carried out in only 20% of the patients. Copyright  2010 ISUOG. Published by John Wiley & Sons, Ltd.

Enevold Falsen - One of the best experts on this subject based on the ideXlab platform.

  • Actinomyces vaccimaxillae sp. nov., from the jaw of a cow.
    International Journal of Systematic and Evolutionary Microbiology, 2003
    Co-Authors: Val Hall, Matthew D. Collins, Roger A Hutson, Elisabeth Inganäs, Enevold Falsen, Brian I Duerden
    Abstract:

    A previously undescribed Actinomyces-like bacterium was isolated from a lesion in the jaw of a cow. Based on its cellular morphology and the results of Biochemical Testing, the organism was tentatively identified as a member of the genus Actinomyces. Comparative 16S rRNA gene sequencing studies showed that the bacterium represents a hitherto unknown species within the genus Actinomyces, and is related to a group of species that includes Actinomyces turicensis and its close relatives. It is proposed that the unknown organism be classified as Actinomyces vaccimaxillae sp. nov. (the type strain is CCUG 46091T=CIP 107423T).

  • Actinomyces oricola sp. nov., from a human dental abscess.
    International journal of systematic and evolutionary microbiology, 2003
    Co-Authors: Val Hall, Matthew D. Collins, Roger A Hutson, Elisabeth Inganäs, Enevold Falsen, Brian I Duerden
    Abstract:

    A previously undescribed Actinomyces-like bacterium was isolated from a human dental abscess. Based on its cellular morphology and the results of Biochemical Testing the organism was tentatively identified as a member of the genus Actinomyces, but it did not correspond to any currently recognized species of this genus. Comparative 16S rRNA gene sequencing studies showed the bacterium represents a hitherto unknown subline within the genus Actinomyces, clustering within a group of species, which includes Actinomyces bovis, the type species of the genus. Based on Biochemical and molecular phylogenetic evidence, it is proposed that the unknown organism recovered from a dental abscess be classified as a new species, Actinomyces oricola sp. nov. The type strain of Actinomyces oricola is R5292(T) (=CCUG 46090(T)=CIP 107639(T)).

  • Actinomyces coleocanis sp. nov., from the vagina of a dog.
    International Journal of Systematic and Evolutionary Microbiology, 2002
    Co-Authors: Lesley Hoyles, Geoffrey Foster, Enevold Falsen, Matthew D. Collins
    Abstract:

    A hitherto undescribed Actinomyces-like bacterium was isolated from the vagina of a dog. Biochemical Testing and PAGE analysis of whole-cell proteins indicated that the isolate was phenotypically different from previously described Actinomyces species and related taxa. Sequencing of 165 rRNA showed that the unknown bacterium was distinct from all currently known Actinomyces species. Phylogenetically, the unidentified organism displayed a specific association with Actinomyces europaeus, but a sequence divergence of > 5% demonstrated that it represents a distinct species. Based on both phenotypic and 165 rRNA sequence considerations, it is proposed that the unknown strain from a dog be classified as a novel species, Actinomyces coleocanis sp. nov. The type strain is CCUG 41708T (= CIP 106873T).

  • characterization of actinomyces isolates from infected root canals of teeth description of actinomyces radicidentis sp nov
    Journal of Clinical Microbiology, 2000
    Co-Authors: Matthew D. Collins, Lesley Hoyles, Natalia Nikolaitchouk, Sotos Kalfas, Goran Sundquist, Tor Monsen, Enevold Falsen
    Abstract:

    Two strains of a previously undescribed Actinomyces-like bacterium were recovered in pure culture from infected root canals of teeth. Analysis by Biochemical Testing and polyacrylamide gel electrophoresis of whole-cell proteins indicated that the strains closely resembled each other phenotypically but were distinct from previously described Actinomyces and Arcanobacterium species. Comparative 16S rRNA gene-sequencing studies showed the bacterium to be a hitherto unknown subline within a group of Actinomyces species which includes Actinomyces bovis, the type species of the genus. Based on phylogenetic and phenotypic evidence, we propose that the unknown bacterium isolated from human clinical specimens be classified as Actinomyces radicidentis sp. nov. The type strain of Actinomyces radicidentis is CCUG 36733.

  • Actinomyces canis sp. nov., isolated from dogs.
    International Journal of Systematic and Evolutionary Microbiology, 2000
    Co-Authors: Lesley Hoyles, Geoffrey Foster, Cristina Pascual, Christina Greko, Enevold Falsen, Matthew D. Collins
    Abstract:

    Three strains of a previously undescribed catalase-positive Actinomyces-like bacterium were isolated from dogs. Biochemical Testing and PAGE analysis of whole-cell proteins indicated that the strains were phenotypically highly related to each other but different from previously described Actinomyces and Arcanobacterium species. Sequencing of 16S rRNA showed that the unknown bacterium represents a new subline within a cluster of species which includes Actinomyces hyovaginalis, Actinomyces georgiae, Actinomyces meyeri, Actinomyces odontolyticus, Actinomyces radingae and Actinomyces turicensis. On the basis of phenotypic evidence and 16S rRNA sequence divergence levels (greater than 5% with recognized Actinomyces species) it is proposed that the unknown strains from canine sources be classified as a new species with the name Actinomyces canis sp. nov. The type strain of Actinomyces canis is CCUG 41706T (= CIP 106351T).