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E Hume

Publications and source records attributed to E Hume.

10 recordsLinked to original sources

MRI in patients with intraspinal bullets.

The purpose of this study was to determine whether neurologic sequelae occur in patients with intraspinal bullets or bullet fragments who undergo magnetic resonance imaging (MRI). Nineteen patients with bullets or bullet fragments adjacent to the cord or nerve roots underwent clinical MRI studies at 1.5 T. Sequences included conventional spin echo, fast spin echo, gradient-recalled echo, and inversion recovery. Patients were queried during scanning for symptoms of discomfort, pain, or change in neurologic status. Detailed neurologic examinations were performed prior to MRI (baseline), post MRI, and at the patients' discharge. Sixteen patients were completely paralyzed (ASIA-A), and three were not paralyzed. The length of time from injury was 2-24 months. No patients experienced pain or discomfort during the procedure. No change in neurologic status occurred. Follow-up radiographic studies showed no bullet movement following the scanning. We conclude that in patients with complete spinal cord injury, MRI in patients with intraspinal bullets may be performed.

Adult

CpG-rich sequences close to the site of duplication within the human IGH constant region.

Human immunoglobulin heavy chains are encoded by a highly complex locus, IGH, which encompasses many transcriptional units, including nine alternative constant region genes. Much of the constant region gene cluster was duplicated during hominoid evolution. In rodents, IGH is known to be regulated by multiple elements, including several enhancers 3' of the alpha chain-encoding A constant region gene, CA, the last transcribed region. Sequences downstream of the two human CA genes, possibly containing homologous enhancer elements, have not yet been reported. By long-range mapping of genomic DNA, a cluster of unmethylated rare restriction sites, representing a potential CpG island, was previously reported downstream of each CA gene, close to the 3' end of the duplicated region. Such potential CpG islands are candidates for additional IGH regulatory elements. We isolated bacteriophage clones containing these clusters of methylation-sensitive restriction sites, which lie within short CpG-rich stretches. Some of these sites showed tissue-specific methylation. 3' of the unmethylated CpG-rich sequences, clones derived from the 5' (telomeric) copy of the duplicated region, contained, in order, endogenous retroviral sequences, a processed ELK1 pseudogene, and the pseudogene IGHGP. Comparison with the presumed 3' (centromeric) copy of the duplicated region showed that similarity was lost exactly at the end of the retroviral long terminal repeat sequences. These results imply that an endogenous retroviral integration was present immediately 3' of IGH in the common hominoid ancestor and suggest models for the duplication of the region.

Base Sequence

BCL6 encodes a sequence-specific DNA-binding protein.

Chromosomal rearrangements of BCL6 are commonly associated with diffuse large-cell lymphomas. We set out to determine the DNA-binding site of a glutathione-S-transferase fusion protein containing the BCL6 zinc finger region by employing cyclic amplification and selection of targets (CASTing). From oligonucleotides containing 16 central random bases, sequences binding to the protein on glutathione-coated beads were repeatedly selected and amplified by polymerase chain reaction (PCR). The binding sites were cloned and sequenced. A consensus, TTTNNNGNNATNCTTT, was obtained. Protein binding studies of double-stranded oligomers containing point mutations within the 3' CTTT confirmed the binding specificity of this part of the consensus. In addition, evidence indicated that some of the base pairs held constant in the oligonucleotides used for CASTing also contributed to binding.

Base Sequence

Genomic structure of the candidate proto-oncogene BCL3.

We previously reported the identification of a novel candidate proto-oncogene involved in the translocation t(14;19)(q32;q13) found in some cases of human B-cell chronic lymphocytic leukemia. This gene, BCL3, is a member of the I kappa B family, whose encoded proteins regulate the NF-kappa B family of transcription factors. Here we describe the genomic structure of BCL3. The gene contains nine exons, spanning 11.5 kb. In comparison to other members of the I kappa B family, there is a remarkable conservation of the exon-intron boundaries in relation to the coding sequences, consistent with an origin from a common ancestral gene. BCL3 is unusual in containing two CpG islands, a 5' island encompassing the first exon, the other lying within the gene. Southern blot analysis using methylation-sensitive restriction enzymes revealed that while the 5' CpG is unmethylated in all tissues tested, the degree of methylation of the internal CpG island varies.

Amino Acid Sequence

Mutation analysis of coding sequences for type I procollagen in individuals with low bone density.

Mutations in one of the two genes encoding type I procollagen (COL1A1 and COL1A2) are frequently the cause of osteogenesis imperfecta (OI), a disorder characterized by brittle bones. Here we tested whether patients with low bone density also have mutations in these genes. The 26 patients studied had no apparent metabolic bone disease, but most had a positive family history of osteopenia or osteoporosis. Although a diagnosis of OI was considered by the clinician in some cases, the clinical criteria for OI were not satisfied. Our strategy for mutation analysis consisted of PCR amplification of cDNA made to fibroblast mRNA using primers specific for the coding regions of COL1A1 and COL1A2. The PCR products were then sequenced directly with primers located within each PCR product. We found that 3 of 26 patients had mutations that altered the encoded amino acid. One mutation, at position alpha 2(I)-661 has been reported (Spotila et al. 1991 Proc Natl Acad Sci USA PNAS 88:5423). The other 2 patients, who were not related to each other, had a mutation that altered the proline codon at alpha 1(I)-27 to alanine. This mutation was not found in 81 normal individuals or in 37 additional osteopenic individuals. However, its effect on the biologic function of type I collagen, as well as its role in osteopenia, is uncertain. In addition to the two mutations, we found a polymorphism in codon alpha 2(I)-459. Although this polymorphism involved an amino acid substitution, it was present with equal frequency in the patient and the normal population. By analyzing this and previously reported neutral sequence variants in the COL1A2 gene, we determined that all patients expressed both alleles of the COL1A2 gene. The 12 patients who were heterozygous for a COL1A1 neutral sequence variant also expressed both alleles. Here we present all PCR primer and sequencing primer information. The results suggest that surveying a larger group of similarly selected individuals may reveal additional mutations in the COL1A1 or COL1A2 genes.

Adolescent

Osteomyelitis of the pelvis/hips in paralyzed patients: accuracy and clinical utility of MRI.

PURPOSE: The goal of our study was to determine the accuracy and clinical utility of MRI in the diagnosis of osteomyelitis of the pelvis/hips in paralyzed patients. METHOD: In 44 paralyzed patients, 59 consecutive MR examinations of the pelvis/hips were evaluated prospectively. Criteria for diagnosis of osteomyelitis were based on those established in previous studies of complex, nonhematogenous osteomyelitis (diabetic foot). Average follow-up was 3 years. The standard of reference for the diagnosis of osteomyelitis was histologic/microbiologic results of surgical biopsy specimens or clinical follow-up. Note was made if decubitus ulcers, sinus tract, fistula, fluid collection, abscess, septic arthritis, joint effusion, bursitis, or heterotopic ossification was present on MRI. Comparison of the extent of infection by MRI and surgical margins was performed. Effect on surgical treatment was defined by absence of recurrent infection at the surgical site within 6 weeks of limited resection. RESULTS: The criteria for diagnosis of osteomyelitis were fulfilled in 49 of 57 MR studies for an overall accuracy of 97%. There was one false-negative MR study. MRI for the diagnosis of osteomyelitis yielded a sensitivity of 98% and a specificity of 89%. There were 41 decubitus ulcers, 28 sinus tracts, 2 fistulae, 14 fluid collections, 15 abscesses, 9 hips with septic arthritis, 10 "bland" hip effusions, 5 cases of trochanteric bursitis, and 30 patients with heterotopic ossification. Twenty-one patients underwent limited surgical resection guided by MR findings in which only the enhancing area was resected. There was only one recurrence of osteomyelitis at the surgical margins. CONCLUSION: MRI is accurate in the diagnosis of osteomyelitis and associated soft tissue abnormalities in spinal cord-injured patients. MRI can delineate the extent of infection in guiding limited surgical resection and preserving viable tissue.

Abscess