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A Hell

Publications and source records attributed to A Hell.

15 recordsLinked to original sources

Donor-derived alloantibodies and passenger lymphocyte syndrome in two of four patients who received different organs from the same donor.

BACKGROUND: Reported here is the occurrence of RBC alloimmunization in two of four patients who received different organs from an immunized donor. STUDY DESIGN AND METHODS: The donor, a 58-year-old woman, was group O D+, K-, and Fy(a-). Initially, her serum contained only a K antibody. After blood transfusion, a second antibody (anti-Fy(a)) could also be identified. The liver was given to a group O D+, K-, Fy(a+) patient; the pancreas and one kidney to a group O D+, K-, Fy(a+) patient; the heart to a group A D+, K-, Fy(a-) patient; and the other kidney to a group B D+, K-, Fy(a+) patient. RBC grouping and antibody screening were performed by standard techniques. Lymphoid microchimerism in the peripheral blood of the recipients was analyzed by flow cytometry and nested PCR. RESULTS: None of the recipients had irregular RBC alloantibodies at the time of transplantation. After the transplant, anti-K became detectable in the serum of the liver recipient, and anti-Fy(a) could be eluted from the RBCs of the liver recipient and the pancreas-kidney recipient. The latter patient also developed mild hemolysis, and his Hb dropped to 8 g per dL on posttransplant Day 9. Donor-derived lymphocytes were detectable by flow cytometry in the peripheral blood of the liver recipient and the pancreas-kidney recipient until Days 8 and 63, respectively, whereas no lymphoid chimerism could be demonstrated in the heart recipient. PCR chimerism analyses were positive in all three recipients over the whole observation period of 97 postoperative days. CONCLUSION: The amount of cotransplanted lymphoid tissue may correlate with the extent of peripheral lymphoid microchimerism and the antibody-formation capacity in solid organ transplantation.

Adult↗

Determination and Successful Transfusion of Anti-Gerbich-Positive Red Blood Cells in a Patient with a Strongly Reactive Anti-Gerbich Antibody.

Background: The clinical relevance of antibodies directed against members of the Gerbich (GE) family of antigens is not invariably clear. Given the scarcity of serologically compatible red blood cells (RBC), various methods may have to be applied to assess the safety of transfusing serologically incompatible RBC. Patient and Methods: The serum of a 57-year-old male Caucasian admitted to hospital for gastrectomy was found to contain a highly reactive anti-GE2 antibody (IgG(1)). In addition to a monocyte monolayer assay, 50 ml of GE2-positive RBC were transfused, and blood samples were taken before and 1 and 24 h after transfusion for flow-cytometric determination of transfused cells. Results: Both tests showed no increased destruction of GE2-positive RBC. The transfusion of 4 units of GE2-positive RBC was well tolerated, and hemoglobin increased adequately. Conclusion: This case may extend the information available not only on antibodies directed against members of the GE family of antigens but also on methods to estimate the survival of transfused RBC. Copyright 2000 S. Karger GmbH, Freiburg

Journal Article↗

Fractionation of chromatin by differential solubility in dilute salt.

Chromatin prepared from the livers of rats was fractionated on the basis of solubility in dilute NaCl. Neither of the fractions obtained was enriched in newly synthesized DNA. The salt-soluble fraction had a higher protein content (usually up to 50%) relative to the DNA, and contained 72% or more of the rapidly synthesized RNA. This RNA was found to be complexed with the salt-soluble deoxyribonucleoprotein, not merely co-solubilized with it. Also, polylysine-binding studies showed that about 70% or more of the nucleic acid phosphates were accessible as compared to about 40% in the unfractionated chromatin. These properties suggested that the soluble fraction was enriched in activity transcribed chromatin. In contrast molecular hybridization studies showed that the complexity of the DNA and its homology with cDNA transcribed from rat-liver polysomal mRNA were the same as those of DNA from unfractionated chromatin, or from the salt-insoluble fraction. This suggests that the criteria commonly accepted as distinguishing between euchromatin and heterochromatin in vitro are not invariably valid.

Animals↗

A new estimate of human ribosomal gene number.

Radioactively labelled DNAs (5 X 10(6) cpm/mug) complementary to human 18 S and 28 S ribosomal RNA were synthesized using RNA-directed DNA polymerase (EC 2.7.7.7). These complementary DNAs were used to measure human ribosomal gene numbers by two independent methods, both of which indicated numbers at least four-fold lower than those previously reported. First, the kinetics of the annealing of the complementary DNAs with total human placental DNA indicated that the number of both 18-S and 28-S ribosomal genes per haploid genome is approximately 50. Second, saturation experiments in which a constant amount of DNA was annealed with increasing amounts of complementary DNA also indicated that the number of 28 S ribosomal RNA genes in human placental and spleen DNA is is about 50 per haploid genome.

DNA↗

Synthesis of DNAs complementary to human ribosomal RNAs polyadenylated in vitro.

Conditions are described under which poly(A) polymerase from Escherichia coli ribosomes will catalyse the addition of AMP residues onto the 3'-ends of human 18 S and 28 S ribosomal RNAs at an average rate of 40 AMP residues per 1000 nucleotides in 20 min. Single-stranded complementary DNAs (cDNAs) can then be transcribed from the polyadenylated RNAs with RNA-directed DNA polymerase from avian myeloblastosis virus. All of the sequences in the RNAs are represented in the cDNAs; measurements of the rates at which the cDNAs hybridize with their template RNAs showed that, when appropriate adjustments for differences in lengths and G + C contents of the reacting sequences are taken into account, the Rot 1/2 values of homologous RNA-cDNA hybridization reactions are directly proportional to the base-sequence complexity of the RNAs.

DNA↗