Triplet morbidity and mortality in a large case series.

OBJECTIVE: A significant increase in the triplet birth rate has occurred recently. This rise is of concern, as these infants are historically reported to be at risk of adverse outcome. Thus, we examined the outcome of triplet births in a large contemporary case series. STUDY DESIGN: Since 1993, detailed clinical data have been collected on all patients admitted to our Neonatal Intensive Care Unit. We retrospectively analyzed this database to examine triplet outcome. RESULTS: A total of 51 consecutive sets of triplets were born over a 9-year period. The mean birth weight for triplets was 1789+/-505 g, mean gestational age was 32.6+/-2.7 weeks, with discordancy present in 17.6% of neonates. Complications of prematurity were infrequent. Triplet survival to discharge was 96%. CONCLUSIONS: This large contemporary case series of triplets demonstrates excellent survival with low associated morbidity. These data suggest that there may no longer be medical justification for offering selective fetal reduction to parents with triplet pregnancies.     

Thymic origin of some natural killer cells: clonal proliferation of human CD3-16+ cells from CD3-4-8- thymocyte precursors requires the presence of H9 leukemic cells.

Purified CD3-4- thymocyte populations were cultured in the presence of interleukin-2 (IL-2) and peripheral blood lymphocytes (PBL) and/or tumor cell lines as a source of irradiated feeder cells. Maximal cell proliferation was obtained in the presence of a mixture of H9 leukemic cells and normal PBL. More importantly, under these culture conditions, 30%-50% of these cells were found to express CD16 surface antigen after 1-2 weeks of culture. Similar proportions of CD16+ cells could be detected in CD3-4- thymocyte populations that had been further depleted of CD16+ cells. Cloning of CD3-4-16- thymocytes under limiting dilution conditions resulted, in the presence of H9 cells, in more than 50% of CD16+ clones (cloning efficiency 3%-8%). Since some of the surface CD3- clones expressed cytoplasmic CD3 antigen, it has been possible to identify four distinct phenotypic groups of clones (CD16+cyCD3+, CD16+cyCD3-, CD16-cyCD3+, CD16-cyCD3-). Independently of their phenotype, all thymus-derived CD3- clones expressed a strong cytolytic activity against natural killer (NK)-sensitive and NK-resistant tumour target cells. In addition, following stimulation with phytohemagglutinin (PHA) and phorbol 12-myristate 13-acetate (or PHA alone) all clones released interferon-gamma and tumour necrosis factor-alpha, but not IL-2. Taken together, our data provide evidence that cells which share their phenotypic and functional properties with CD3-CD16+ NK cells can be derived from thymic precursors.     

Hb-M "Hyde Park": a de novo mutation, identified by mass spectrometry and DNA analysis.

BACKGROUND. Structural hemoglobinopathies usually are inherited as autosomic dominant traits; de novo mutations are uncommon. Analytical and preparative procedures for the characterization of an abnormal hemoglobin are complex and time-consuming. Mass spectrometer analysis allows a rapid identification of the amino acid substitution. METHODS AND RESULTS. A cyanotic 7-year-old girl was found to have 16% methemoglobin. Laboratory data showed the presence of an abnormal hemoglobin, which was isolated by collecting the abnormal peak from DEAE and globin chains from CM52. The amino acid substitution was rapidly identified by FAB mass spectroscopic analysis, leading to the recognition of HbM Hyde Park. These data were confirmed by molecular analysis (Southern blot and DNA sequencing). Neither the parents nor a sister showed any abnormality; non-paternity was excluded by blood group serology and HLA typing. CONCLUSIONS. This is a case of HbM Hyde-Park arising as a de novo mutation. FAB mass spectroscopic analysis is a rapid and useful analytical method for identifying aminoacid substitution.     

Kidney transplant monitoring by anti donor specific antibodies

Donor-specific anti-HLA antibodies were studied by cytotoxicity crossmatching (CTXM) and flow cytometry crossmatching (FCXM) in 117 kidney transplant candidates; the same study was carried out in 33 cadaver-donor kidney recipients, during the first 3 post-transplant months, for which donor cells were available. Pre-transport evaluation showed that 82.9 % of subjects were CTXM negative/FCXM negative, 6.8 % of patients were positive in both tests, and 10.3 % were CTXM negative/FCCM positive. Post-transplant monitoring for donor-specific antibodies (Abs-DS) showed that nine recipients (27.3 %) were FCXM positive; six of them were IgG + and three IgM +. In comparing these results with the clinical course, a significant association between FCXM IgG + and rejection episodes was observed (P < 0.01).     

Personality variables as moderators between hassles and subjective indications of distress

The research was designed to investigate the moderating effect of some personality traits on subjective distress caused by daily hassles. The traits were internal locus of control, repression, ego strength, and barrier (as studied and defined by S. Fisher). The last two variables were negatively correlated both with the somatic and emotional distress indications and with the frequency of hassles reportED; internal locus of control showed an inverse relationship only with frequency of hassles. The hypothesis is formulated that ego strength and barrier are personality factors influencing not only the outcomes of coping (ie the stress response), but also event appraisal.     

Severe glomerular epithelial cell damage does not prevent passive Heyman nephritis in rats.

Analysis of the local cell-mediated immunity within the central nervous system is limited by the small amount of material available. In the present report we describe that T lymphocyte clones can be expanded directly from the cerebrospinal fluid (CSF) using T cell growth factor and irradiated feeder cells. Without in vitro restimulation such clones can reproducibly be generated from fresh or cryopreserved CSF lymphocytes. From a patient with tuberculous meningitis, T lymphocyte clones were obtained that showed tuberculin (PPD) specific proliferative responses restricted by a single HLA-DR antigen. One of these clones was restricted by an antigen different from the serologically defined HLA-DR since this clone recognized PPD only on autologous but not on HLA-DR matched monocytes. These experiments show that T lymphocytes involved in the in situ immune response can be cloned directly from the site of inflammation.     

Detection of Trypanosoma cruzi and Trypanosoma rangeli infection by duplex PCR assay based on telomeric sequences

We used the species specificity and repetitious nature of subtelomeric kinetoplastida sequences to generate a duplex PCR assay for the simultaneous detection of Trypanosoma cruzi and Trypanosoma rangeli in experimentally and naturally infected triatomine (Reduviid) bugs and in infected human subjects. The assay was species specific and was capable of detecting 1/20th of T. cruzi and 1/4th of T. rangeli cell equivalents without complementary hybridization. In addition, the PCR-based assay was robust enough for direct application to difficult biological samples such as Reduviid feces or guts and was capable of recognizing all T. cruzi and T. rangeli strains and lineages. Because the assay primers amplify entirely different target sequences, no reaction interference was observed, facilitating future adaptation of this assay to an automated format.     

PG-M1: A New Monoclonal Antibody Directed against a Fixative-Resistant Epitope on the Macrophage-Restricted Form of the CD68 Molecule

A new anti-macrophage monoclonal antibody (PG-M1) was produced by immunizing BALB/c mice with fresh spleen cells from a patient with Gaucher's disease. PG-M1 reacts strongly with a fixative-resistant epitope of an intracytoplasmic molecule, selectively expressed by virtually all macrophages of the human body. Although attempts to immunoprecipitate the molecule recognized by PG-M1 have failed so far, the reactivity of the antibody with COS-1 and WOP cells transfected with a human complementary DNA clone encoding for the CD68 antigen suggests that PG-M1 is a new member of the CD68 cluster. However, unlike other CD68 antibodies (KP1, EBM11, etc.), which react with both macrophages and myeloid cells, PG-M1 detects a fixative-resistant epitope on the macrophage-restricted form of the CD68 antigen. In 957 routinely fixed, paraffin-embedded samples, PG-M1 showed a more restricted reactivity with elements of the monocyte/macrophage lineage than the previously described monoclonal antibodies MAC-387 (anti-calgranulins), KP1 (CD68) and Ki-M1P. Among hematological malignancies, PG-M1 only labels acute leukemias of M4 and M5 type and rare examples of malignant histiocytosis/true histiocytic sarcoma. In contrast, acute leukemias of the M1, M2, M3, M6, M7, and L1-L3 types, non-Hodgkin's lymphomas, and Hodgkin and Reed-Sternberg cells of Hodgkin's disease are consistently PG-M1-negative. In the daily diagnostic practice, PG-M1 seems to be particularly valuable for the diagnosis of myelomonocytic or monocytic leukemia and neoplasms of true histiocytic origin in routine paraffin sections.