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L A Tully

Publications and source records attributed to L A Tully.

6 recordsLinked to original sources
PubMed2000

A sensitive denaturing gradient-Gel electrophoresis assay reveals a high frequency of heteroplasmy in hypervariable region 1 of the human mtDNA control region.

A population study of heteroplasmy in the hypervariable region 1 (HV1) portion of the human mtDNA control region was performed. Blood samples from 253 randomly chosen individuals were examined using a sensitive denaturing gradient-gel electrophoresis (DGGE) system. This method is capable of detecting heteroplasmic proportions as low as 1% and virtually all heteroplasmy where the minor component is > or = 5%. Heteroplasmy was observed in 35 individuals (13.8%; 95% confidence interval [CI] 9.6-18.0). Of these individuals, 33 were heteroplasmic at one nucleotide position, whereas 2 were heteroplasmic at two different positions (a condition known as "triplasmy"). Although heteroplasmy occurred at a total of 16 different positions throughout HV1, it was most frequently observed at positions 16093 (n=13) and 16129 (n=6). In addition, the majority of heteroplasmic variants occurred at low proportions and could not be detected by direct sequencing of PCR products. This study indicates that low-level heteroplasmy in HV1 is relatively common and that it occurs at a broad spectrum of sites. Our results corroborate those of other recent reports indicating that heteroplasmy in the control region is more common than was previously believed-a finding that is of potential importance to evolutionary studies and forensic applications that are based on mtDNA variation.

Base Sequence↗
PubMed2000

The triple P-positive parenting program: a comparison of enhanced, standard, and self-directed behavioral family intervention for parents of children with early onset conduct problems.

Three variants of a behavioral family intervention (BFI) program known as Triple P were compared using 305 preschoolers at high risk of developing conduct problems. Families were randomly assigned to enhanced BFI (EBFI), standard BFI (SBFI), self-directed BFI (SDBFI), or wait list (WL). At postintervention, the 2 practitioner-assisted conditions were associated with lower levels of parent-reported disruptive child behavior, lower levels of dysfunctional parenting, greater parental competence, and higher consumer satisfaction than the SDBFI and WL conditions. Overall, children in EBFI showed greater reliable improvement than children in SBFI, SDBFI, and WL. By 1-year follow-up, children in all 3 conditions achieved similar levels of clinically reliable change in observed disruptive behavior. However, the EBFI and SBFI conditions showed greater reliable improvement on parent-observed disruptive child behavior.

Age of Onset↗
PubMed1999

Comparative identity and homogeneity testing of the mtDNA HV1 region using denaturing gradient gel electrophoresis.

A denaturing gradient gel electrophoresis (DGGE) assay has been developed for comparative identity and homogeneity testing of the mtDNA HV1 region. A total of 49 pairs of sequences, each pair differing by a single unique polymorphism, were tested to verify the reliability of the assay. Discrimination between all pairings was achieved as judged by the resolution of the mismatch-containing heteroduplexes from the fully base-paired homoduplexes. In all but two pairings, resolution of the fully base-paired homoduplexes was also obtained. Sequence pairs differing by multiple polymorphisms were also tested and resulted in a greater separation between the homo- and heteroduplexes. Additional information derived from the technique includes the identification of co-amplifying contaminating or heteroplasmic samples in the independent samples lanes. Thirteen heteroplasmic samples, six at positions distinct from those analyzed in the pairwise comparison study, were analyzed and the heteroplasmic positions identified unambiguously by sequencing the excised bands. The technique constitutes a conceptually simple, accurate, and inexpensive test for determining whether two sequences match within the mtDNA HV1 region, while providing a more definitive control for the identification of co-amplifying contaminating or heteroplasmic sequences than is presently available.

Amino Acid Sequence↗
PubMed1997

Mealtime behavior and parent-child interaction: a comparison of children with cystic fibrosis, children with feeding problems, and nonclinic controls.

Examined the role of family interaction factors in dietary compliance problems reported by parents of children with cystic fibrosis (CF). The family mealtime interactions of children with CF, children with feeding problems and nonclinic controls were observed, and parents monitored children's eating behavior at home. Parents of children with CF reported more concern about feeding problems and recorded more disruptive mealtime behavior than parents of nonclinic children. Observational data showed children with CF to display overall rates of disruptive mealtime behavior not significantly different from either comparison group. Mothers of children with CF were observed to engage in higher rates of aversive interaction with their child than did mothers of nonclinic controls. Fathers of children with CF reported lower marital satisfaction than fathers of controls. Both mothers and fathers of children with CF reported lower parenting self-efficacy than non-CF families. Clinical implications are discussed.

Child↗
PubMed1996

Characterization of mitochondrial DNA using low-stringency single specific primer amplification analyzed by laser induced fluorescence--capillary electrophoresis.

Polymerase chain reaction (PCR)-based DNA typing is routinely used in forensics for identity testing. Those assays that distinguish single nucleotide polymorphisms (SNPs) require other biochemical reactions in addition to PCR to identify the sequence polymorphisms. Low-stringency sequence-specific PCR (LSSP-PCR) is an example of a recent method that does not require additional biochemical treatments. The analysis of LSSP-PCR by capillary electrophoresis (CE) to discriminate the highly polymorphic mitochondrial DNA (mtDNA) D-loop region is described. The DNA from five individuals were amplified (first step) using sequence-specific primers to produce 1021 bp fragments containing the D-loop region. Each fragment was isolated by electroelution using CE and UV detection, and subjected to a second amplification (second step) using a single primer annealed under low stringency conditions. This generated a range or profile of PCR products for each sample, which were resolved and analyzed by CE with the intercalator TOTO-1 and laser-induced fluorescence (LIF) detection. The LSSP-PCR profiles were unique for each individual, indicating that this technique may be applicable for forensic identity testing.

DNA Primers↗