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At least 217 records · Page 12Linked to original sources
PubMed1988

Four-year experience with exclusive use of cytomegalovirus antibody (CMV-Ab)-negative donors for CMV-Ab-negative kidney recipients.

Because of unacceptable CMV related morbidity, mortality, and graft loss, we adopted a policy that (-) patients would receive renal allografts only from (-) donors. This policy has resulted in a significant decrease in (1) morbidity (10.6% v 1.7%, P less than .0001), (2) mortality (3.7%) v 0%, P = .002), and (3) graft loss (2.5% v 0%, P = .016). CMV-Ab-negative patients (1) constitute 26% of all patients tested (compared with 36% of all donors tested), (2) receive transplants at the same rate as (+) patients, (3) do not have a prolonged waiting time, and (4) received greater HLA-A, B, -DR mismatched kidneys (3.6 v 3.1, P less than .01).

Antibodies, Viral↗
PubMed1994

GPI phospholipase C from Trypanosoma brucei causes a GPI-negative phenotype in Leishmania major: I. Implications for GPI-negative mammalian cells; II. Compartmentalization of two GPI biosynthetic pathways.

The major surface macromolecules of the protozoan parasite Leishmania major, gp63 (a metalloprotease), and lipophosphoglycan (a polysaccharide) are glycosylphosphatidylinositol (GPI)-anchored. We expressed a cytoplasmic glycosylphosphatidylinositol phospholipase C (GPIPLC) in L. major in order to examine the topography of the protein-GPI and polysaccharide-GPI pathways. In L. major cells expressing GPIPLC cell-associated gp63 could not be detected in immunoblots. gp63 was secreted into the culture medium without ever receiving a GPI anchor. Putative protein-GPI intermediates LP-1 and LP-2 decreased about 10-fold. In striking contrast, lipophosphoglycan levels were unaltered. We conclude that reactions specific to the polysaccharide-GPI pathway are compartmentalized within the endoplasmic reticulum, thereby sequestering those intermediates from GPIPLC cleavage. Protein-GPI synthesis, at least up to production of Man(1 alpha 6)Man(1 alpha 4)GlcN(1 alpha 6)-myo-inositol-1-phospholipid, is cytosolic. To our knowledge, this represents the first use of a catabolic enzyme, in vivo, to elucidate the topography of biosynthetic pathways. Intriguingly, the phenotype of GPIPLC-expressing L. major, secretion of proteins with GPI addition signals, and depletion of protein-GPI anchor precursors, is similar to that of some protein-GPI mutants in higher eukaryotes. These findings have implications for paroxysmal nocturnal hemoglobinuria and Thy-1-negative T-lymphoma.

Animals↗
PubMed1991

Molecular diagnosis of Philadelphia negative CML using the polymerase chain reaction and DNA analysis: clinical features and course of M-bcr negative and M-bcr positive CML.

The Philadelphia chromosome (Ph) is the cytogenetic hallmark of chronic myeloid leukemia (CML) and as such has been used to confirm the diagnosis of CML based on morphological and clinical criteria. We have investigated 12 patients who were considered to have clinical and morphological features of CML and who did not have detectable abnormalities of chromosomes 9q34 or 22q11. In six of the 12 patients, rearrangement within the 5.8 kb major breakpoint region (M-bcr) and amplification of CML specific M-bcr-ABL cDNA sequences by the polymerase chain reaction (PCR) was demonstrated. Six other CML patients did not have rearrangement of the M-bcr gene or amplification of BCR-ABL by PCR. These patients had atypical CML. They were significantly older, most had less than 10% immature granulocytic cells (metamyelocytes, myelocytes and promyelocytes) and had various degrees of marrow fibrosis. Three of these six patients died of blastic transformation at 4, 15 and 54 months from diagnosis.

Adult↗
PubMed2002

Factor XIII deficiency mistaken for battered child syndrome: case of "correct" test ordering negated by a commonly accepted qualitative test with limited negative predictive value.

We report herein a case of Factor XIII deficiency that remained undiagnosed until 2 years of age. Part of the delay in diagnosis was a consequence of testing that was performed on a blood sample obtained after plasma transfusion therapy for a life-threatening bleeding episode. Due to insufficient family follow-up after discharge from the hospital, the diagnosis was delayed 1 year until the child was rehospitalized and a pre-transfusion plasma sample was tested. The commonly accepted approach of using only a qualitative test for the diagnosis of factor XIII deficiency is challenged by this case report.

Battered Child Syndrome↗
PubMed1988

Relationship of molecular radical anion abundance and calculated lowest unoccupied molecular orbital energies for polychlorinated dibenzofurans and dibenzodioxins in electron capture negative ion mass spectrometry: evidence for negative metastable ions.

Relationships were found between experimentally measured molecular radical anion abundances and calculated lowest unoccupied molecular orbital energies (epsilon LUMO) for polychlorodibenzofurans and polychlorodibenzo-p-dioxins. Anion abundances were measured using standard mass spectrometric techniques, while epsilon LUMO were calculated by the 'Complete Neglect of Differential Overlap' method. Polychlorodibenzofurans with calculated epsilon LUMO greater than or equal to 1.6 eV show 0% molecular radical anion and those with epsilon LUMO less than or equal to 1.4 eV show greater than or equal to 80% molecular radical anion abundance. Similarly, the molecular radical anion is absent for polychlorodibenzo-p-dioxins with calculated epsilon LUMO greater than or equal to 2.0 eV. A trend towards greater molecular radical ion relative abundance appears for 2.0 eV greater than or equal to epsilon LUMO greater than or equal to 1.0 eV and a maximum is reached around 1 eV, whereupon the molecular ion abundance diminishes with lower epsilon LUMO. B/E linked scan analysis indicates that chlorodioxins with epsilon LUMO less than 1 eV give increasing amounts of metastable anions.

Benzofurans↗