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L Flaherty

Publications and source records attributed to L Flaherty.

At least 55 records · Page 3Linked to original sources
PubMed1997

Reln(rl-Alb2), an allele of reeler isolated from a chlorambucil screen, is due to an IAP insertion with exon skipping.

The reeler Albany2 mutation (Reln(rl-Alb2) in the mouse is an allele of reeler isolated during a chlorambucil mutagenesis screen. Homozygous animals had drastically reduced concentrations of reelin mRNA, in which an 85-nt exon was absent. At the genomic level, the mutation was shown to be due to an intracisternal A-particle insertion leading to exon skipping. This appears to be the first observation of retrotransposon insertion during chlorambucil mutagenesis.

Alleles↗
PubMed1997

A high-resolution genetic map around waltzer on mouse chromosome 10 and identification of a new allele of waltzer.

A new autosomal recessive mouse mutation characterized by deafness and circling behavior was recovered during mutagenesis experiments with chlorambucil (CHL). On the basis of allelism tests and linkage analyses, this mutation appears to represent a new allele of waltzer (v) that maps to mouse Chromosome (Chr) 10. We have designated this new allele, Albany waltzer (vAlb). A high-resolution map of the region around v was constructed from data from two intersubspecific backcrosses involving Mus musculus castaneus. The analysis of 648 backcross mice has allowed vAlb to be localized 1.1 +/- 0.4 cM distal to D10Mit60 and 0.2 +/- 0.2 cM proximal to a cluster of four markers, D10Mit172, D10Mit112, D10Mit48, and D10Mit196. An independent backcross was used to confirm the map order and distances in the vAlb backcross. The two linkage maps were consistent, indicating that the lesion in vAlb, which is presumed to be a deletion based on the known action of CHL, is small and has not significantly altered the map at this level of detection. Additionally, three genes (Ros1, Grik2, and Zfa) were eliminated as possible candidates for vAlb, and several SSLP markers were separated genetically.

Alleles↗
PubMed1997

IAP insertion in the murine LamB3 gene results in junctional epidermolysis bullosa.

The laminin-5 molecule functions in the attachment of various epithelia to basement membranes. Mutations in the laminin-5-coding genes have been associated with Herlitz junctional epidermolysis bullosa (HJEB), a severe and often lethal blistering disease of humans. Here we report the characterization of a spontaneous mouse mutant with an autosomal recessive blistering disease. These mice exhibit sub-epithelial blisters of the skin and mucosal surfaces and abnormal hemidesmosomes lacking sub-basal dense plates. By linkage analysis the genetic defect was localized to a 2-cM region on distal Chromosome (Chr) 1 where a laminin-5 subunit gene, LamB3, was previously localized. LamB3 mRNA and laminin-5 protein were undetectable by Northern blot analysis and immunohistochemical methods, respectively. DNA sequence analysis indicated that the LamB3 genetic defect resulted from disruption of the coding sequence by insertion of an intracisternal-A particle (IAP) at an exon/intron junction. These findings suggest a role for laminin-5 in hemidesmosome formation and indicate that the LamB3(IAP) mutant is a useful mouse model for HJEB.

Animals↗
PubMed1997

Quantitative trait loci analysis affecting contextual conditioning in mice.

In an extensive backcross of mice between C3H/HeJ (C3H) and C57BL/6J (B6), we sought to map genes that influence learning and memory as measured by performance in a contextual fear-conditioning paradigm. Our results indicate that there are several genetic regions that have a strong influence on performance in this paradigm. The strongest influences map to the proximal and distal ends of chromosome 1 (lod scores of 5.14 and 4.76, respectively). Other chromosomal regions (chromosomes 3, 7, 8, 9 and 18) were also identified as candidates for regions containing genes influencing contextual fear conditioning, with lod scores ranging from 1.8 to 2.7.

Animals↗
PubMed1997

Increased survival of patients treated with a vaccinia melanoma oncolysate vaccine: second interim analysis of data from a phase III, multi-institutional trial.

OBJECTIVE: The efficacy of vaccinia melanoma oncolysate (VMO) vaccine to increase overall survival and disease-free survival of patients with surgically resected International Union Against Cancer (UICC) stage II melanoma was studied in a phase III, randomized, multi-institutional trial. SUMMARY BACKGROUND DATA: Phase I and II trials with VMO showed minimal toxicity and clinical efficacy in patients with melanoma. In a recently completed phase III VMO trial, the first interim analysis performed in April 1994 showed an increasing trend in the survival of patients treated with VMO. The second interim analysis was performed in April 1995. METHODS: Patients with surgically resected stage II (UICC) melanoma were treated with VMO (N = 104) or placebo vaccinia vaccine virus (V) (N = 113) once a week for 13 weeks and then once every 2 weeks for a total of 12 months. Patients' clinical data were collected as of May 1995 and analyzed for survival. RESULTS: In this second interim analysis, the mean follow-up time is 42.28 months. No survival difference was observed between VMO and V treatments. However, in a retrospective subset analysis, a subset of males between the ages of 44 and 57 years and having one to five positive nodes (at 2-, 3-, and 5-year intervals, 13.6%, 15.9%, and 20.3% difference insurvival in favor of VMO [N = 20] when compared to V [N = 18] [p = 0.037]) and another subset of patients with clinical stage I (at 3- and 5-year intervals, 30% and 7% difference in survival in favor of VMO [N = 20] when compared to V [N = 23], [p = 0.05]) showed significant survival advantage with VMO. CONCLUSIONS: Although VMO vaccine therapy in surgical adjuvant setting did not produce a significant survival benefit to all patients with melanoma, patients from the above two subsets had significant survival benefit.

Adult↗
PubMed1997

Treatment of malignant melanoma with interleukin-2.

Treatment of metastatic malignant melanoma with recombinant interleukin-2 (rIL-2) represents one of the earliest attempts at systemic immunomodulation as a therapy for cancer. Initial reports showed objective response rates with single-agent rIL-2 therapy in the range of 15% to 20% with some durable responses; however, the overall response rates were lower than originally anticipated. In addition, in contrast to animal models, it appears that coadministration of lymphokine-activated killer (LAK) cells, generated ex vivo with rIL-2, does not enhance the response rates achieved with single-agent rIL-2. Despite a multitude of studies with various rIL-2 regimens, with and without coadministration of LAK cells or tumor-infiltrating lymphocytes, the optimum dose and treatment schedule for rIL-2-based therapy in metastatic melanoma remains a topic of controversy. To date, there are also no clear immunologic parameters that can predict biologic response to rIL-2-based therapy.

Clinical Trials as Topic↗
PubMed1996

Fine genetic map of mouse chromosome 10 around the polycystic kidney disease gene, jcpk, and ankyrin 3.

A chlorambucil (CHL)-induced mutation of the jcpk (juvenile congenital polycystic kidney disease) gene causes a severe early onset polycystic kidney disease. In an intercross involving Mus musculus castaneus, jcpk was precisely mapped 0.2 cM distal to D10Mit115 and 0.8 cM proximal to D10Mit173. In addition, five genes, Cdc2a, Col6a1, Col6a2, Bcr, and Ank3 were mapped in both this jcpk intercross and a (BALB/c x CAST/Ei)F1 x BALB/c backcross. All five genes were eliminated as possible candidates for jcpk based on the mapping data. The jcpk intercross allowed the orientation of the Ank3 gene relative to the centromere to be determined. D10Mit115, D10Mit173, D10Mit199, and D10Mit200 were separated genetically in this cross. The order and genetic distances of all markers and gene loci mapped in the jcpk intercross were consistent with those derived from the BALB/c backcross, indicating that the CHL-induced lesion has not generated any gross chromosomal abnormalities detectable in these studies.

Animals↗
PubMed1996

Recovery of probes linked to the jcpk locus on mouse chromosome 10 by the use of an improved representational difference analysis technique.

Representational difference analysis (RDA) is a subtractive hybridization technique by which the differences between two complex genomes can be isolated. An improved version of this technique was used to isolate DNA segments that map to a narrow genetic region adjacent to the jcpk locus on Chromosome 10 of the mouse. A mutation at this locus acts recessively and causes an early onset polycystic kidney disease. Genomic subtractions involving DNA from C57BL/6 (B6) and its partially congenic partner, B6-jcpk/jcpk, produced 39 restriction fragments (difference products), 25 of which were unique and represented differences in BglII sites between these two strains. Although none identified the jcpk locus itself, 7 of these were mapped to an interval between 3.4 and 6.5 cM distal to the jcpk locus. Five of these 7 difference products were developed by subtracting B6-jcpk/jcpk from B6 DNA, but only 1 of the 5 was isolated using the original RDA technique. The other 4 were obtained by an improved technique that included size selection of difference products after the third round of subtractive hybridization and amplification. The remaining 2 of the mapped products resulted from the reciprocal subtraction experiment using the improvements. Thus, by this improved technique and two-way subtraction, we were able to add seven new markers to a relatively small genetic region on Chromosome 10.

Animals↗
PubMed1996

Phase I trial of Adozelesin using the treatment schedule of daily x5 every 3 weeks.

CC-1065 is a unique alkylating agent that preferentially binds in the minor groove of double-stranded DNA at adenine-thymine-rich sites. Although it has broad antitumor activity in preclinical models its development was discontinued because of deaths observed during preclinical toxicology studies. Adozelesin is a potent synthetic analog that was chosen for clinical development because it had a similar preclinical antitumor spectrum, but did not produce deaths similar to CC-1065 at therapeutic doses. Phase I evaluations using a variety of Adozelesin treatment schedules have been conducted. This report describes our experience using a multiple dose treatment schedule. Endpoints including antitumor response, maximum tolerated dose, dose limiting toxicity as well as other toxicities and the recommended Phase II starting dose were determined. Adozelesin was given as a 10 minute IV infusion for 5 consecutive days every 21 days or upon recovery from toxicity. The dose range evaluated was 6-30 mcg/m2/day. All patients had refractory solid tumors and had received prior cytotoxic treatment. Thirty-three patients (22 men: 11 women) were entered onto the study and 87 courses were initiated. Dose limiting toxicity was cumulative myelosuppression (leucopenia, thrombocytopenia). The maximum tolerated dose was 30 mcg/m2/day. The only other significant toxicity was an anaphylactoid syndrome that occurred in 2 patients. A partial response was observed in a patient with refractory soft tissue sarcoma. The recommended Phase II starting dose of Adozelesin using a 10 minute IV infusion for 5 consecutive days is 25 mcg/m2/day to be repeated every 4-6 weeks to allow recovery from myelotoxicity, based on our experience. Additional Phase I and II studies with Adozelesin are recommended.

Adult↗
PubMed1996

Evidence that two phenotypically distinct mouse PKD mutations, bpk and jcpk, are allelic.

Numerous mouse models of polycystic kidney disease (PKD) have been described. All of these diseases are transmitted as single recessive traits and in most, the phenotypic severity is influenced by the genetic background. However, based on their genetic map positions, none of these loci appears to be allelic and none are candidate modifier loci for any other mouse PKD mutation. Previously, we have described the mouse bpk mutation, a model that closely resembles human autosomal recessive polycystic kidney disease. We now report that the bpk mutation maps to a 1.6 CM interval on mouse Chromosome 10, and that the renal cystic disease severity in our intersubspecific intercross progeny is influenced by the genetic background. Interestingly, bpk co-localizes with jcpk, a phenotypically-distinct PKD mutation, and complementation testing indicates that the bpk and jcpk mutations are allelic. These data imply that distinct PKD phenotypes can result from different mutations within a single gene. In addition, based on its map position, the bpk locus is a candidate genetic modifier for jck, a third phenotypically-distinct PKD mutation.

Alleles↗
PubMed1996

Developmental expression of the mouse MHC Q genes.

To investigate the role of class Ib genes in the Q region of the mouse major histocompatibility complex (MHC), the developmental expression and foetal tissue distribution of the Q genes were studied in the C57BL/6 mouse. Using RNase protection assays, we examined Q gene expression in a wide spectrum of foetal tissues at different stages of gestation, Q4, Q6 and Q8 were widely expressed in a variety of tissues. In contrast, the expression of Q1 was restricted to the thymus and intestinal epithelium.

Animals↗
PubMed1995

MHC class I gene organization in > 1.5-Mb YAC contigs from the H2-M region.

Sixteen yeast artificial chromosome (YAC) clones have been mapped to the H2-M region at the distal end of the mouse major histocompatibility complex (MHC) on chromosome 17. Analysis of the YACs with single- and multicopy probes yielded a proximal contig spanning a minimum of 800 kb and a distal contig of 700 kb. A probe for the conserved fourth exon of MHC class I genes detected 19 restriction fragments, including 6 of the 8 previously characterized H2-M class I genes, in the proximal contig. This contig spans the gap from the M to the T region and includes the T1 gene. By contrast, only two class I genes, M2 and M3, were found in the distal contig. These two genes, which are both expressed, may mark the end of the MHC. The order among nine class I genes and seven other markers was determined in the cloned DNA from the centromere as T1, Tu32A, (M1-M7-M8), Tu32B, B30, M6, M4, M5, Mog, Tu42A parallel M2, Leh525, M3, Tu42B, where the orientation with respect to the centromere is unknown for M1-M7-M8.

Animals↗