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Gail Stetten

Publications and source records attributed to Gail Stetten.

8 recordsLinked to original sources
PubMed2007

Use of T-cell antibodies for donor dosaging in a canine model of in utero hematopoietic stem cell transplantation.

AIM: Microchimerism following canine in utero hematopoietic stem cell transplantation (IUHSCT) development of T-cell dosing regimens. OBJECTIVE: To investigate the use of anti-T-cell antibodies for cell dosing of the donor graft in a canine model of IUHSCT. STUDY DESIGN: Canine IUHSCT was performed by ultrasound-guided intraperitoneal injection in days 35-38 of fetal canines with CD34(+) cells at doses of 4.5 x 10(8) to 1.3 x 10(9) cells/kg and T cells (CD3(+) CD5(+)) at doses of 8 x 10(6) to 8.8 x 10(8) cells/kg. Postnatal studies included tissue histology and polymerase chain reaction-based chimerism analysis. RESULTS: Term survival was 86-100%. Microchimerism (0-2%) was detected in five of eight recipients in multiple tissues. Histopathology revealed no evidence of graft-versus-host disease (GVHD). CONCLUSION: Canine IUHSCT is a useful model to investigate the role of donor T cells in engraftment and GVHD. IUHSCT at early gestational ages with high doses of donor T cells in the graft yields microchimerism in multiple tissues without GVHD.

Animals↗
PubMed2005

Autopsy findings of a 37-year-old man with a complex mosaic karyotype involving del(18p), monosomy 13, and trisomy 20.

We report on the autopsy findings of a 37-year-old man with a complex karyotype (mos46,XY,del(18)(p11.1)[14]/46,XY, -13, del (18)(p11.1), +20[8]/47,XY,del(18)(p11.1), +20[8]). He was known to be blind, non-ambulatory, have severe mental retardation, and a seizure disorder. External physical findings at the time of autopsy included micrognathia, short stubby fingers, and rocker bottom feet. Left lobe dominance of the liver and mislocation of the ileocecal junction and appendix were noted on internal examination. The brain was small (700 g) and poorly developed. Microscopically it showed an absence of neurons in the olivary and dentate nuclei, absence of Purkinje cells in the cerebellum, severe depletion of internal granular cells in the cerebellum, and cerebellar dysplasia. Fat infiltration was noted in an unusual distribution in several organs including a pattern in the heart consistent with arrythmogenic right ventricular dysplasia (ARVD). Findings of this mosaic chromosomal karyotype have not been previously described. This report will discuss this individuals physical findings and their relation to similar monochromosomal aberrations.

Abnormalities, Multiple↗
PubMed2005

A reciprocal translocation 46,XY,t(8;9)(p11.2;q13) in a bladder exstrophy patient disrupts CNTNAP3 and presents evidence of a pericentromeric duplication on chromosome 9.

A patient with sporadic bladder exstrophy and de novo apparently balanced chromosomal translocation 46,XY,t(8;9)(p11.2;q13) was analyzed by fluorescence in situ hybridization (FISH) and molecular methods. We were able to map both translocation breakpoints to single genomic clones. The chromosome 8p11.2 breakpoint was mapped to BAC clone RP4-547J18, predicted to contain several hypothetical genes. Characterization of the chromosome 9q13 breakpoint indicated a disruption in the 5' region of CNTNAP3 within BAC RP11-292B8. This observation suggests possible involvement of CNTNAP3 in the etiology of bladder exstrophy. Additionally, FISH analysis identified several genomic copies of CNTNAP3 on both sides of the chromosome 9 centromere flanking the polymorphic heterochromatin. Northern blot analysis of lymphoblast and bladder RNA confirmed CNTNAP3 transcripts in these tissues and did not show abnormal CNTNAP3 expression in the proband and two unrelated patients with bladder exstrophy. The identification of multiple copies of three BAC clones in the proband, his parents, and unrelated controls suggests that duplications of CNTNAP3 and the surrounding genomic region have occurred as a result of repeated events of unequal crossing over and pericentric inversions during chromosome 9 evolution.

Base Sequence↗
PubMed2004

Reevaluating confined placental mosaicism.

Chromosomal mosaicism was found in 38 of 4,000 chorionic villus samples examined from 1998 to 2003. A small fraction of these (5/38) were confirmed as true mosaics by analysis of amniotic fluid. Twenty-nine cases that fit the definition of confined placental mosaicism were followed with clinical and cytogenetic analysis throughout the pregnancy, at birth and in a few cases into infancy. This was done to determine the prognostic interpretation of prenatal cytogenetic results from multiple specimens in a single pregnancy and thus allow for reevaluation of the genetic counseling. In 2 of these 29 cases, low-level mosaicism was found in the neonate, and in 1 of these the chromosome abnormality is probably the cause of the resulting minor phenotypic abnormalities. Families face unique difficulties when confined placental mosaicism is the prenatal diagnosis, and it is extremely important that the counseling they receive takes into consideration the unlikely possibility of the placental abnormality appearing in fetal tissues.

Chorionic Villi Sampling↗
PubMed2004

In utero hematopoietic stem cell transplantation with haploidentical donor adult bone marrow in a canine model.

OBJECTIVE: Chimerism can be achieved in a canine model of in utero bone marrow transplantation with > or =1 x 10(8) CD34(+) haploidentical donor cells per kilogram without graft-versus-host disease. STUDY DESIGN: In utero bone marrow transplantation was performed by ultrasound-guided intraperitoneal infusion in 30- to 41-day-old canines with CD34(+) selected cells from paternal bone marrow at doses of 1.3 x 10(8) to 2.5 x 10(10) CD34(+) cells/kg. A method for marking control littermates was developed with intraperitoneal ethiodol. Postnatal studies included histologic, fluorescent in situ hybridization canine Y probe, and polymerase chain reaction-based chimerism analyses. RESULTS: Term survival was 86% to 100% for transplantations > or =34 days versus 14% and 43% at 30 and 31 days. Microchimerism (<1%) was demonstrated in tissues from 4 informative litters that included thymus, liver, skin, spleen, and intestine. Neither gestational age nor donor CD34 cell dosage altered the level of engraftment in these experiments. There was no evidence of graft-versus-host disease. CONCLUSION: In utero bone marrow transplantation in a canine model achieves microchimerism with high CD34(+) cell doses.

Animals↗
PubMed2004

Transcript level alterations reflect gene dosage effects across multiple tissues in a mouse model of down syndrome.

Human trisomy 21, which results in Down syndrome (DS), is one of the most complicated congenital genetic anomalies compatible with life, yet little is known about the molecular basis of DS. It is generally accepted that chromosome 21 (Chr21) transcripts are overexpressed by about 50% in cells with an extra copy of this chromosome. However, this assumption is difficult to test in humans due to limited access to tissues, and direct support for this idea is available for only a few Chr21 genes or in a limited number of tissues. The Ts65Dn mouse is widely used as a model for studies of DS because it is at dosage imbalance for the orthologs of about half of the 284 Chr21 genes. Ts65Dn mice have several features that directly parallel developmental anomalies of DS. Here we compared the expression of 136 mouse orthologs of Chr21 genes in nine tissues of the trisomic and euploid mice. Nearly all of the 77 genes which are at dosage imbalance in Ts65Dn showed increased transcript levels in the tested tissues, providing direct support for a simple model of increased transcription proportional to the gene copy number. However, several genes escaped this rule, suggesting that they may be controlled by additional tissue-specific regulatory mechanisms revealed in the trisomic situation.

Animals↗
PubMedDate not supplied

Prenatal detection of an interstitial deletion in 4p15 in a fetus with an increased nuchal skin fold measurement.

OBJECTIVES: The detection of an increased nuchal translucency (NT) or nuchal fold (NF) measurement is associated with an increased risk of common aneuploidies. Only rarely is it associated with other types of chromosome abnormalities. We report the prenatal finding of an increased NF in a fetus with an interstitial 4p deletion. METHODS: Standard karyotype analysis was followed by FISH with research generated BAC probes to precisely map the 4p deletion. RESULTS: The karyotype of the fetus was determined to be 46,XX,del(4)(p15.2p16.1) by G-banding analysis and was refined to 46,XX,del(4) (p15.1p15.32) after FISH analysis. The breakpoints were narrowed to 150 kb regions on each side. The deletion is approximately 14.5 Mb, containing approximately 47 genes. CONCLUSIONS: We report a case of an increased NF measurement associated with a 4p deletion. A literature review revealed a previous case of a 4p deletion in a fetus with an increased NT. Since chromosome deletions are rarely associated with an increased NT or NF, we believe it is significant that a 4p deletion has now been found in two unrelated cases. We mapped the deletion with BAC probes, generating a list of possible candidate genes involved in the pathogenesis of increased nuchal skin folds.

Chromosomes, Human, Pair 4↗