Helen Lawce | Oregon Health & Science University (original) (raw)

Papers by Helen Lawce

Research paper thumbnail of Human chromosomes: identification and variations

John Wiley & Sons, Inc. eBooks, Mar 4, 2017

Research paper thumbnail of The cell and cell division

John Wiley & Sons, Inc. eBooks, Mar 4, 2017

Research paper thumbnail of Interphase FISH for Residual Disease: Proposal for a Qualitative Determination of Rare Events

PubMed, 2019

Interphase fluorescence in situ hybridization (FISH) cutoff values are calculated using various m... more Interphase fluorescence in situ hybridization (FISH) cutoff values are calculated using various mathematical methods to determine whether abnormalities seen are at reportable (statistically significant) levels. However, for interphase FISH studies of samples obtained from oncology patients who have been transplanted or treated, these cutoff values may result in reporting a false negative result due to the small percentage of residual disease that falls below such a cutoff value. Failure to detect the rare abnormal cells may impact patient care and prognosis. For such situations, the two questions are: is the disease still present, and if so, how prevalent is it? The first question is qualitative and the second is quantitative. Traditionally, only the quantitative parameters have been used for determining reportability. Here we propose a method to account for both qualitative and quantitative evaluations of interphase FISH results.

Research paper thumbnail of Technical Problem with Amniotic Fluid Cultures

Research paper thumbnail of Cytogenetics: an overview

John Wiley & Sons, Inc. eBooks, Mar 4, 2017

Research paper thumbnail of Chromosome stains

John Wiley & Sons, Inc. eBooks, Mar 4, 2017

Research paper thumbnail of X-autosome translocation with a 47,XXXY qs,t(9p-;Xq+) karyotype

PubMed, 1975

A male with a karyotype 47,XXXY qs,t(9p-;Xq+) was ascertained utilizing ASG-banding. The karyotyp... more A male with a karyotype 47,XXXY qs,t(9p-;Xq+) was ascertained utilizing ASG-banding. The karyotype was repeated because the original diagnosis of Klinefelter syndrome (47,XXY) was inconsistent with many of the stigmata present. It is suggested that many karyotypes completed prior to the advent of banding techniques will be repeated in an attempt to provide more accurate diagnosis, describe more aberrations, and possibly establish new syndromes.

Research paper thumbnail of Fluorescence in situ hybridization (FISH)

John Wiley & Sons, Inc. eBooks, Mar 4, 2017

Research paper thumbnail of Microscopy and imaging

Research paper thumbnail of Karyological and biochemical evidence for chromosomal dedifferentiation in neoplasia

In Vitro Cellular & Developmental Biology – Plant, Feb 1, 1972

Research paper thumbnail of Chromosome analysis guidelines – preliminary report

Cytogenetic and Genome Research, 1990

Research paper thumbnail of Bone Marrow Transfusions in Previously Irradiated, Hematologically Normal Syngeneic Mice

Experimental Biology and Medicine, Mar 1, 1981

Transfusion of syngeneic marrow into normal, nonirradiated recipients results only in minimal pro... more Transfusion of syngeneic marrow into normal, nonirradiated recipients results only in minimal proliferation of donor cells. However, irradiated recipients, restored to hematologic normalcy by an initial marrow transfusion, subsequently sustain proliferation which replaces approximately 10% of endogenous marrow after a single transfusion of 4 x 10⁷ marrow cells of the same strain as the host. Cells from histoincompatible donors proliferate

Research paper thumbnail of Prenatal diagnosis of 45,X/46,XX mosaicism: True mosaicism in only one of four primary cultures

Prenatal Diagnosis, Mar 1, 1984

45,X/46,XX mosaicism was found in only one of four primary amniotic fluid cultures. Repeat amnioc... more 45,X/46,XX mosaicism was found in only one of four primary amniotic fluid cultures. Repeat amniocentesis revealed 45,X/46,XX mosaicism in all four primary cultures. Mosaicism was confirmed in tissues from the abortus.

Research paper thumbnail of The AGT Cytogenetics Laboratory Manual

John Wiley & Sons, Inc. eBooks, Apr 12, 2017

Research paper thumbnail of Bone Marrow Transfusions in Previously Irradiated, Hematologically Normal Syngeneic Mice

Experimental Biology and Medicine, 1981

Transfusion of syngeneic marrow into normal, nonirradiated recipients results only in minimal pro... more Transfusion of syngeneic marrow into normal, nonirradiated recipients results only in minimal proliferation of donor cells. However, irradiated recipients, restored to hematologic normalcy by an initial marrow transfusion, subsequently sustain proliferation which replaces approximately 10% of endogenous marrow after a single transfusion of 4 x 10⁷ marrow cells of the same strain as the host. Cells from histoincompatible donors proliferate

Research paper thumbnail of Technical Problem with Amniotic Fluid Cultures

Journal of the Association of Genetic Technologists, Feb 1, 2003

Research paper thumbnail of Interphase FISH for Residual Disease: Proposal for a Qualitative Determination of Rare Events

OBJECTIVES Interphase fluorescence in situ hybridization (FISH) cutoff values are calculated usin... more OBJECTIVES Interphase fluorescence in situ hybridization (FISH) cutoff values are calculated using various mathematical methods to determine whether abnormalities seen are at reportable (statistically significant) levels. However, for interphase FISH studies of samples obtained from oncology patients who have been transplanted or treated, these cutoff values may result in reporting a false negative result due to the small percentage of residual disease that falls below such a cutoff value. Failure to detect the rare abnormal cells may impact patient care and prognosis. For such situations, the two questions are: is the disease still present, and if so, how prevalent is it? The first question is qualitative and the second is quantitative. Traditionally, only the quantitative parameters have been used for determining reportability. Here we propose a method to account for both qualitative and quantitative evaluations of interphase FISH results.

Research paper thumbnail of Split centromeric alpha-satellite FISH signals in a whole arm translocation 5p;10p: consequences and implications for interphase FISH studies

This is a case report of an apparently balanced whole arm translocation between the short arms of... more This is a case report of an apparently balanced whole arm translocation between the short arms of chromosomes 5 and 10 in which the centromeric alpha-satellite DNA is split between both derivative chromosomes for both probes, leading to abnormal signal patterns. The patient requested preimplantation genetic testing for the unbalanced products of the translocation. However, using centromeric alpha-satellite DNA probes as controls for the subtelomeric-specific probes in interphase was not informative because of the split signals. The ramifications of such variation in the alpha-satellite regions of chromosomes for other interphase FISH tests are discussed.

Research paper thumbnail of The role for preimplantation genetic diagnosis in balanced translocation carriers

Research paper thumbnail of A New Rhesus Macaque Karyotype Based on Human-rhesus Synteny

Journal of the Association of Genetic Technologists, 2016

Rhesus macaque (Macaca mulatta), because of their similarity to humans, are often used to study c... more Rhesus macaque (Macaca mulatta), because of their similarity to humans, are often used to study complex neurobiology and anatomy, cardiovascular disease, and in vaccine development. While the rhesus genome is studied on its own by primatologists, the grand majority of rhesus macaque research is done with the intention of extrapolating the findings to human diseases and traits. As such, it makes sense that the rhesus genome and karyotype be arranged based on homology to human chromosomes in an effort to ease the comparisons between the two, and aide in interpreting data generated using rhesus macaque model systems. Various approaches have been utilized, including linkage analyses using radiation hybrid markers and human microsatellite loci, and next generation sequencing, to create a comprehensive rhesus genome. Here, we present for the first time, the rhesus macaque karyotype adjusted and renumbered to reflect human homology, and to complement the newly completed sequencing data.

Research paper thumbnail of Human chromosomes: identification and variations

John Wiley & Sons, Inc. eBooks, Mar 4, 2017

Research paper thumbnail of The cell and cell division

John Wiley & Sons, Inc. eBooks, Mar 4, 2017

Research paper thumbnail of Interphase FISH for Residual Disease: Proposal for a Qualitative Determination of Rare Events

PubMed, 2019

Interphase fluorescence in situ hybridization (FISH) cutoff values are calculated using various m... more Interphase fluorescence in situ hybridization (FISH) cutoff values are calculated using various mathematical methods to determine whether abnormalities seen are at reportable (statistically significant) levels. However, for interphase FISH studies of samples obtained from oncology patients who have been transplanted or treated, these cutoff values may result in reporting a false negative result due to the small percentage of residual disease that falls below such a cutoff value. Failure to detect the rare abnormal cells may impact patient care and prognosis. For such situations, the two questions are: is the disease still present, and if so, how prevalent is it? The first question is qualitative and the second is quantitative. Traditionally, only the quantitative parameters have been used for determining reportability. Here we propose a method to account for both qualitative and quantitative evaluations of interphase FISH results.

Research paper thumbnail of Technical Problem with Amniotic Fluid Cultures

Research paper thumbnail of Cytogenetics: an overview

John Wiley & Sons, Inc. eBooks, Mar 4, 2017

Research paper thumbnail of Chromosome stains

John Wiley & Sons, Inc. eBooks, Mar 4, 2017

Research paper thumbnail of X-autosome translocation with a 47,XXXY qs,t(9p-;Xq+) karyotype

PubMed, 1975

A male with a karyotype 47,XXXY qs,t(9p-;Xq+) was ascertained utilizing ASG-banding. The karyotyp... more A male with a karyotype 47,XXXY qs,t(9p-;Xq+) was ascertained utilizing ASG-banding. The karyotype was repeated because the original diagnosis of Klinefelter syndrome (47,XXY) was inconsistent with many of the stigmata present. It is suggested that many karyotypes completed prior to the advent of banding techniques will be repeated in an attempt to provide more accurate diagnosis, describe more aberrations, and possibly establish new syndromes.

Research paper thumbnail of Fluorescence in situ hybridization (FISH)

John Wiley & Sons, Inc. eBooks, Mar 4, 2017

Research paper thumbnail of Microscopy and imaging

Research paper thumbnail of Karyological and biochemical evidence for chromosomal dedifferentiation in neoplasia

In Vitro Cellular & Developmental Biology – Plant, Feb 1, 1972

Research paper thumbnail of Chromosome analysis guidelines – preliminary report

Cytogenetic and Genome Research, 1990

Research paper thumbnail of Bone Marrow Transfusions in Previously Irradiated, Hematologically Normal Syngeneic Mice

Experimental Biology and Medicine, Mar 1, 1981

Transfusion of syngeneic marrow into normal, nonirradiated recipients results only in minimal pro... more Transfusion of syngeneic marrow into normal, nonirradiated recipients results only in minimal proliferation of donor cells. However, irradiated recipients, restored to hematologic normalcy by an initial marrow transfusion, subsequently sustain proliferation which replaces approximately 10% of endogenous marrow after a single transfusion of 4 x 10⁷ marrow cells of the same strain as the host. Cells from histoincompatible donors proliferate

Research paper thumbnail of Prenatal diagnosis of 45,X/46,XX mosaicism: True mosaicism in only one of four primary cultures

Prenatal Diagnosis, Mar 1, 1984

45,X/46,XX mosaicism was found in only one of four primary amniotic fluid cultures. Repeat amnioc... more 45,X/46,XX mosaicism was found in only one of four primary amniotic fluid cultures. Repeat amniocentesis revealed 45,X/46,XX mosaicism in all four primary cultures. Mosaicism was confirmed in tissues from the abortus.

Research paper thumbnail of The AGT Cytogenetics Laboratory Manual

John Wiley & Sons, Inc. eBooks, Apr 12, 2017

Research paper thumbnail of Bone Marrow Transfusions in Previously Irradiated, Hematologically Normal Syngeneic Mice

Experimental Biology and Medicine, 1981

Transfusion of syngeneic marrow into normal, nonirradiated recipients results only in minimal pro... more Transfusion of syngeneic marrow into normal, nonirradiated recipients results only in minimal proliferation of donor cells. However, irradiated recipients, restored to hematologic normalcy by an initial marrow transfusion, subsequently sustain proliferation which replaces approximately 10% of endogenous marrow after a single transfusion of 4 x 10⁷ marrow cells of the same strain as the host. Cells from histoincompatible donors proliferate

Research paper thumbnail of Technical Problem with Amniotic Fluid Cultures

Journal of the Association of Genetic Technologists, Feb 1, 2003

Research paper thumbnail of Interphase FISH for Residual Disease: Proposal for a Qualitative Determination of Rare Events

OBJECTIVES Interphase fluorescence in situ hybridization (FISH) cutoff values are calculated usin... more OBJECTIVES Interphase fluorescence in situ hybridization (FISH) cutoff values are calculated using various mathematical methods to determine whether abnormalities seen are at reportable (statistically significant) levels. However, for interphase FISH studies of samples obtained from oncology patients who have been transplanted or treated, these cutoff values may result in reporting a false negative result due to the small percentage of residual disease that falls below such a cutoff value. Failure to detect the rare abnormal cells may impact patient care and prognosis. For such situations, the two questions are: is the disease still present, and if so, how prevalent is it? The first question is qualitative and the second is quantitative. Traditionally, only the quantitative parameters have been used for determining reportability. Here we propose a method to account for both qualitative and quantitative evaluations of interphase FISH results.

Research paper thumbnail of Split centromeric alpha-satellite FISH signals in a whole arm translocation 5p;10p: consequences and implications for interphase FISH studies

This is a case report of an apparently balanced whole arm translocation between the short arms of... more This is a case report of an apparently balanced whole arm translocation between the short arms of chromosomes 5 and 10 in which the centromeric alpha-satellite DNA is split between both derivative chromosomes for both probes, leading to abnormal signal patterns. The patient requested preimplantation genetic testing for the unbalanced products of the translocation. However, using centromeric alpha-satellite DNA probes as controls for the subtelomeric-specific probes in interphase was not informative because of the split signals. The ramifications of such variation in the alpha-satellite regions of chromosomes for other interphase FISH tests are discussed.

Research paper thumbnail of The role for preimplantation genetic diagnosis in balanced translocation carriers

Research paper thumbnail of A New Rhesus Macaque Karyotype Based on Human-rhesus Synteny

Journal of the Association of Genetic Technologists, 2016

Rhesus macaque (Macaca mulatta), because of their similarity to humans, are often used to study c... more Rhesus macaque (Macaca mulatta), because of their similarity to humans, are often used to study complex neurobiology and anatomy, cardiovascular disease, and in vaccine development. While the rhesus genome is studied on its own by primatologists, the grand majority of rhesus macaque research is done with the intention of extrapolating the findings to human diseases and traits. As such, it makes sense that the rhesus genome and karyotype be arranged based on homology to human chromosomes in an effort to ease the comparisons between the two, and aide in interpreting data generated using rhesus macaque model systems. Various approaches have been utilized, including linkage analyses using radiation hybrid markers and human microsatellite loci, and next generation sequencing, to create a comprehensive rhesus genome. Here, we present for the first time, the rhesus macaque karyotype adjusted and renumbered to reflect human homology, and to complement the newly completed sequencing data.