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T Gleeson

Publications and source records attributed to T Gleeson.

9 recordsLinked to original sources
PubMed2005

Comparative performance evaluation of the HIV-1 LiPA protease and reverse transcriptase resistance assay on clinical isolates.

BACKGROUND: Assays that provide information regarding HIV-1 resistance to antiretroviral drugs are widely used to help manage antiretroviral treatment. The most commonly used HIV genotypic resistance assays are based on DNA sequencing (TRUGENE, ViroSeq, and home-brew) or reverse hybridization (LiPA). OBJECTIVES: This study compares the results from clinical specimens using two assay methods: the LiPA HIV-1 protease (PR) and reverse transcriptase (RT) resistance assay and DNA sequencing. STUDY DESIGN: Operators at each of three sites tested 10-20 randomly selected clinical specimens using LiPA (three strips total with probes for PR codons 30, 46, 48, 50, 54, 82, 84, and 90, and RT codons 41, 69, 70, 74, 75, 103, 106, 151, 181, 184, and 215) and DNA sequencing (TRUGENE) HIV-1 Genotyping Assay or home-brew methodology). Results from the two methods were categorized for each codon as follows: (i) concordant (LiPA and sequencing having the same result for wild-type (WT), mutant, and mixture); (ii) partially concordant (mixture by one method and not by the other); (iii) indeterminate (no result by LiPA); and (iv) discordant (LiPA and sequencing detecting different amino acids). RESULTS: A total of 50 clinical specimens were tested using the LiPA PR strip; 40 of these were also tested using the LiPA RT strip. For PR, 91.3% of the codon results were concordant, 3.0% were partially concordant, 4.5% were indeterminate by LiPA, and 1.3% were discordant. For RT, 88.0% of the codon results were concordant, 5.9% were partially concordant, 5.2% were indeterminate, and 0.9% were discordant. LiPA detected 3.0% (PR) and 6.4% (RT) WT/mutant mixtures, compared to 0.5% (PR) and 3.2% (RT) mixtures by sequencing. CONCLUSIONS: More WT/mutant mixtures were detected using LiPA, possibly indicating increased sensitivity. Relatively high concordance and low discordance rates were observed between LiPA and DNA sequencing. The indeterminate rate for LiPA was moderately high and may limit the clinical utility of this assay.

Codon↗
PubMed2005

A comparison of whole-body MRI and CT for the staging of lymphoma.

OBJECTIVE: Our objective was to compare whole-body MRI and CT for the staging of lymphoma. CONCLUSION: Whole-body MRI represents an alternative to CT in the staging of lymphoma, with an ability to stage disease, identify lymph nodes greater than 1.2 cm, and the additional ability to evaluate for the presence or absence of disease spread to bone marrow. CT allows detection of more nodes (< 1.2 cm) than MRI but this does not alter tumor stage.

Adult↗
PubMed2001

Identification of a new plasmid-encoded sec-dependent bacteriocin produced by Listeria innocua 743.

Listeria innocua 743 produces an inhibitory activity demonstrating broad-spectrum inhibition of Listeria monocytogenes isolates. Gel-electrophoretic analysis of culture supernatants indicated that two inhibitors with different molecular weights were produced by this strain. Insertion of Tn917 into a 2.9 Kb plasmid (pHC743) generated mutants with either an impaired ability or a loss in ability to produce one of the inhibitors. Sequence analysis of the transposon insertion regions revealed the presence of two continuous open reading frames, the first encoding a new pediocin-like bacteriocin (lisA) and the second encoding a protein homologous with genes involved in immunity toward other bacteriocins (lisB). Translation of the bacteriocin gene (lisA) initiates from a noncanonical start codon and encodes a 71-amino-acid prebacteriocin which lacked the double glycine leader peptidase processing site common in other type II bacteriocins. Alignment of the sequence with the processed N termini of related bacteriocins suggests that the mature bacteriocin consists of 43 amino acids, with a predicted molecular mass of 4,484 Da. Mutants containing insertions into lisA were sensitive to the inhibitor, indicating that lisAB forms a single operon and that lisB represents the immunity protein. Cloning of an amplicon containing the lisAB operon into Escherichia coli resulted in expression and export of the bacteriocin. This finding confirms that the phenotype is dependent on the structural and immunity gene only and that export of this bacteriocin is sec dependent. This is the first confirmation of bacteriocin production in a Listeria spp., and it is of interest that this bacteriocin is closely related to the pediocin family of bacteriocins produced by lactic acid bacteria.

Amino Acid Sequence↗
PubMed1997

Use of ultrasound to determine need for laparotomy in trauma patients.

STUDY OBJECTIVE: To determine whether abdominal ultrasound can be used routinely as the primary screening test to identify the need for laparotomy in trauma patients. METHODS: Ultrasound was used at a Level II trauma center as a primary screening test for evaluation of intraabdominal injury. We reviewed the charts of all patients from trauma codes presenting between January 1, 1991, and December 31, 1993, to determine the results of abdominal ultrasound evaluation and to learn whether laparotomy was required. RESULTS: A total of 2,013 trauma patients presented during the study interval. Ultrasound was performed in 1,631 patients as the primary screening test for abdominal injury (mean time after arrival, 22.9 minutes), abdominal computed tomography (CT) was performed as the primary screen on 8 (mean time, 68.6 minutes), and 93 patients underwent both ultrasound and CT of the abdomen. Of 86 patients requiring laparotomy who were screened by ultrasound, 80 had positive diagnostic findings, for a sensitivity of 93.0%. Of the 1,545 ultrasound-screened patients who did not require laparotomy, 1,390 had negative findings, for a specificity of 90.0%. None of the patients with negative ultrasound results died or sustained identifiable mortality as a consequence of their negative scans. CONCLUSION: Ultrasound is a sensitive and specific test with which to evaluate trauma patients for abdominal injury requiring surgery. Routine abdominal ultrasound can be performed at the bedside in the emergency department as a timely, noninvasive diagnostic test. This use of a screening abdominal ultrasound examination can improve clinical decision-making for the use of emergency laparotomy. Ultrasound may be a better alternative to CT or diagnostic peritoneal lavage for the initial screening evaluation of abdominal trauma.

Abdominal Injuries↗
PubMed1995

Expression of clusterin (testosterone-repressed prostate message-2) mRNA during growth and regeneration of rat liver.

Clusterin has been used as a marker for apoptosis (often denoted "active" "or programmed" cell death) in the prostate, mammary gland and other solid organs. The protein is thought to be involved in membrane remodelling during separation of apoptotic cells from their vital neighbours and fragmentation into apoptotic bodies. In the present study, we have looked at the expression of clusterin during the growth and regression of rat liver induced by short term administration of the hepatomitogen, cyproterone acetate. The steady state level of clusterin mRNA, as measured by Northern and slot blot analysis, is low in control hepatocytes. Following administration of cyproterone acetate, the clusterin mRNA level is increased during both liver growth and regression. In situ hybridization reveals that clusterin is expressed in all hepatocytes, indicating that it is not confined to cell death by apoptosis. These results suggest that the gene product may be involved in maintaining membrane integrity, which is necessary during both mitosis and apoptosis. To determine whether clusterin mRNA is induced by membrane remodelling independent of either mitosis or apoptosis, we examined the expression of clusterin mRNA in the liver after a necrogenic dose of carbon tetrachloride. During the first 24-48 h of this time period, necrosis is the predominant form of cell death and liver regeneration starts after approximately 24 h. Elevated levels of clusterin mRNA are found as early as 12 h after carbon tetrachloride administration and persist for at least 72 h.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Developmental expression of the S35-S45/SGP-2/TRPM-2 gene in rat testis and epididymis.

Testosterone-repressed prostate message-2 (TRPM-2) was originally isolated and cloned from the regressing ventral prostate of the rat. In this tissue, and in other hormone-dependent tissues such as the mammary gland, this gene is induced in the absence of the appropriate trophic hormone. Sequence analysis of the cDNA and genomic clones of TRPM-2 have demonstrated that the coding sequence of this gene is identical to S35-S45 (also known as SGP-2 and clusterin), which is constitutively expressed by the Sertoli cells of the adult testis. Using Northern, slot blot, S1-nuclease analysis, and in situ hybridization, we have investigated the regulation of TRPM-2 expression in the testis and epididymis during development. Slot blot analysis of RNA extracted from the testis and epididymis of 7-, 14-, 28-, 35-, and 91-day-old rats demonstrates that the gene is induced to detectable levels between days 7 and 14 and that the relative level of expression does not change significantly after day 14. In situ hybridization using frozen sections of testis from day 2-, 7-, 14-, 28-, 35-, and 91-day-old rats confirms that there is little expression of TPRM-2 in the seminiferous epithelium of 7-day-old rats, but this increases considerably after 14 days, primarily in Sertoli cells but also in association with meiotic developing spermatogenic cells. However, TRPM-2 mRNA is expressed in the rete testis at 2 days of age, reaches a peak at 35 days of age, and continues to be expressed in the adult. Slot blot analysis demonstrates that TRPM-2 is also induced in the epididymis between 7 and 14 days of age, although, as has been demonstrated by in situ hybridization, TRPM-2 mRNA is detectable in the epithelial cells in the head of the epididymis but is barely detectable in the midportion or tail regions. Northern analysis suggests that the size of the TRPM-2 transcript in the testis also changes during development. In the early stages of testicular development, the TRPM-2 transcript appears to be a broad band of approximately 1.5 kb, while the transcript in the adult appears to be approximately 1.8 kb in length. S1-nuclease protection assays suggest that this increase in size is not due to differential splicing of the first exon of TRPM-2/SGP-2 and most probably reflects a difference in the polyadenylation of the mRNA in the testis at different times during development.

Animals↗
PubMed1991

A trace display and editing program for data from fluorescence based sequencing machines.

'Ted' (Trace editor) is a graphical editor for sequence and trace data from automated fluorescence sequencing machines. It provides facilities for viewing sequence and trace data (in top or bottom strand orientation), for editing the base sequence, for automated or manual trimming of the head (vector) and tail (uncertain data) from the sequence, for vertical and horizontal trace scaling, for keeping a history of sequence editing, and for output of the edited sequence. Ted has been used extensively in the C.elegans genome sequencing project, both as a stand-alone program and integrated into the Staden sequence assembly package, and has greatly aided in the efficiency and accuracy of sequence editing. It runs in the X windows environment on Sun workstations and is available from the authors. Ted currently supports sequence and trace data from the ABI 373A and Pharmacia A.L.F. sequencers.

Animals↗