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The first 25 amino acids of brome mosaic virus (BMV) coat protein include 8 basic and no acidic residues and are implicated in binding the encapsidated RNA. Using infectious transcripts from BMV RNA3 cDNA clones, we modified this region of the coat gene. A coat protein mutant with the first 25 amino acids deleted failed to direct either packaging of viral RNA in protoplasts or systemic infection of whole barley plants. Neither symptoms, virions, nor viral RNA was detectable in plants inoculated with this mutant or a mutant with a frameshift mutation in the coat gene. Mutants with the normal start codon changed to AAG or with the first eight codons deleted allowed translation to start at a downstream AUG, resulting in a deletion of the first 7 amino acids of the mature wild-type coat protein. These mutants not only packaged viral RNA in protoplasts but directed symptomatic, systemic infections that developed with normal speed and degree of spread within the host. The AUG-to-AAG point substitution did not revert to the wild type after long-term culture in planta. Wild-type BMV virions were also found to contain small amounts of a protein that coelectrophoresed with the truncated coat protein produced by the viable AAG and eight-codon-deletion mutants. This minor coat protein species presumably arose by infrequent translation initiation at the second AUG in the wild-type coat protein gene. Absence of encapsidation-competent coat protein appeared to stimulate production of nonstructural proteins in protoplast infections.

The finding of thrombocytopenia with normal or increased megakaryocytes on bone marrow aspirate supports the diagnosis of ITP. It is essential, however, that every effort be made to exclude other causes of the consumption of platelets. Most cases of chronic ITP are immune in origin; consequently, steroid therapy is the initial treatment of choice, followed by splenectomy if indicated. Twenty-five per cent of patients fail to respond to either treatment modality; however, bleeding manifestations are often mild even when a response in the platelet count is not achieved. Although acute ITP is often self-limiting, exacerbations and remissions may occur in both acute and chronic types of ITP.

We have instituted hospital-wide proficiency testing of nursing personnel who operate glucose-monitoring instruments. Whole blood samples with known glucose levels were distributed to all nursing units for analysis on a biweekly basis. Measurements obtained by nurses on glucose meters were compared with one another and with true glucose levels to identify discrepant performance and institute corrective action. After 10 months of operation, we found that the nursing units using glucose meters daily showed mean absolute variation from true glucose of 12.7% (range, 10.0% to 17.7%), whereas intermittent users showed mean absolute variation of 15.3% (range, 10.7% to 24.0%). Of 552 total paired determinations, 199 (36.9%) differed from true glucose by greater than 15%. This program was successful in establishing uniform quality control procedures among nonlaboratory personnel who had no previous experience in laboratory measurements.

Idiopathic thrombocytopenic purpura (ITP) occurs more commonly in young women and is one of the commonest immune mediated disorders in pregnancy. It may exist as an incidental finding in an otherwise healthy pregnant woman or may be associated with symptomatic reduction in the platelet count and varying degrees of clinical hemorrhage. The condition termed incidental thrombocytopenia of pregnancy is invariably associated with a platelet count of greater than 100 x 10(9)/L and a very low incidence of fetal thrombocytopenia. Symptomatic thrombocytopenia is more commonly associated with low platelet counts in the fetus (estimated between 20%-40%). It has recently been suggested that the incidence of fetal thrombocytopenia is substantially lower than this figure. The management of ITP in pregnancy is complicated by the fact that fetal thrombocytopenia is difficult to diagnose and carries substantial risks during the delivery process with rare cases of fetal hemorrhage occurring spontaneously in utero. Unfortunately there are no laboratory studies that can be performed precisely in the mother that may predict the occurrence of fetal thrombocytopenia. Maternal management is usually directed towards treatment of maternal symptoms. Maternal treatment or response to treatment is inconsistently associated with predictable changes in the fetal platelet count. Obstetric management is aimed at reducing the risks of life threatening fetal hemorrhage occurring at the time of delivery, and fetal management is directed towards the obtaining of fetal platelet samples in order to plan an appropriate strategy for obstetrical delivery. Fetal blood samples are obtained either by a scalp vein puncture at the time of delivery or earlier in gestation by the use of the newer technique termed percutaneous umbilical blood sampling. Fetuses with platelet counts of less then 50 x 10(9)/L are generally delivered by cesarean section whereas those with counts greater than 50 x 10(9)/L are allowed to proceed with vaginal delivery assuming no obstetrical contraindications exist. The use of IVIgG therapy during pregnancy has theoretical implications on improving platelet counts in the mother in situations of severe hemorrhage, however cannot be considered to be appropriate treatment for the prevention of fetal thrombocytopenia, since the exogenous transport of IVIgG across the placenta appears to be inconsistent and unpredictable.(ABSTRACT TRUNCATED AT 400 WORDS)

Tomato (Lycopersicon esculentum Mill. cv New Yorker) plants subjected to 100 millimolar NaCl plus Hoagland nutrients exhibited a pattern of wilting, recovery of turgor, and finally recovery of growth at a reduced level, which required 3 days. During the nongrowing, adaptation phase there were immediate increases in free hexoses and sucrose which declined to near control levels as growth resumed. There was a steady increase in myo-inositol content which reached its maximal level at the time of growth resumption. The myo-inositol level then remained elevated for the remainder of the experiment. Myo-inositol constituted two-thirds of the soluble carbohydrate in leaves and three-fourths of the soluble carbohydrate in roots of salt-adapted plants. Plants which were alternated daily between salt and control solutions accumulated less myo-inositol and exhibited less growth than the continuously salt-treated plants. In L. pennellii and in salt-tolerant and salt-sensitive breeding lines selected from L. esculentum x L. pennellii BC(1) and F(8), myo-inositol content was highest in the most tolerant genotypes, intermediate in the normal cultivar, and lowest in the sensitive genotype after treatment with salt.

Interferon alfa-2b (Intron A; Schering Plough) has been shown to be active in advanced previously treated multiple myeloma (MM). Recent in vitro evidence has suggested synergy between cytotoxic agents and interferon alfa-2b. This phase I-II protocol was initiated to study interferon alfa-2b in combination with melphalan and prednisone. Groups of five patients received interferon alfa-2b twice-weekly for two weeks at dose levels of 0.5, 1.0, 2.0, 5.0 and 10.0 X 10(6) IU/m2. During week 2, melphalan (9 mg/m2) and prednisone (40 mg/m2) were administered concurrently with interferon alfa-2b followed by a rest period during nadir myelosuppression, the cycles being repeated every 28 days. Thirty patients were entered of whom 21 were Stage III, 3 Stage II and 6 Stage I. Median nadir WBC/mm3 and platelets/mm3 at the various dose levels are given in the table. Serious adverse reactions while on study included myocardial infarction, renal failure and leukopenia-related sepsis. Early response information is available. Twenty-six patients are evaluable for response. Seven have had progressive disease and 19 (69%) a partial response, the median duration was 11+ months. Interferon alfa-2b does not appear to antagonize melphalan/prednisone effectiveness and may be additive or synergistic. Full evaluation of this combination will be undertaken in randomized controlled trials which are now underway.

Four pregnancies managed with erythrocyte membrane oral therapy because of severe Rh disease are presented. Reduction in anti-(D) production was the goal of the study. A patient was classified as having severe Rh immunization if there was a history of fetal loss due to erythroblastosis fetalis prior to 26 weeks.

A woman with metastatic breast carcinoma developed acute haemolytic anaemia on two occasions following treatment with methotrexate (MTX) and 5-fluorouracil (5-FU). The direct antiglobulin test was positive. Compatible control cells were pretreated with either MTX or 5-FU and subsequently incubated with patient and control sera. Agglutination in the indirect antiglobulin test was observed only in the presence of patient serum and MTX, and did not occur following pretreatment with 5-FU, folic acid, folinic acid or triamterene. There was no evidence of complement binding to the red cell surface. A macrophage assay showed increased phagocytic uptake of MTX-treated cells in the presence of patient serum. This phagocytosis was not enhanced by the addition of complement. The antibody subclass was predominantly IgG-3. The 51Cr red cell survival of autologous MTX cells was markedly shortened, indicating rapid in vivo destruction. These studies demonstrate the occurrence of acute haemolytic anaemia due to an IgG-3 antibody that reacts with erythrocytes in the presence of methotrexate. This antibody does not fix complement, but sensitizes red blood cells to phagocytosis by macrophages.

Brome mosaic virus (BMV) is an icosahedral virus with a tripartite RNA genome which infects monocotyledonous plants, while the cowpea or legume strain of tobacco mosaic virus (CcTMV) is a rod-shaped virus with a single component RNA genome which infects dicotyledonous plants. To examine the potential for exchanging entire genes between RNA viruses, biologically active cDNA clones were used to replace the natural coat gene of BMV RNA3 with the coat gene and encapsidation origin of CcTMV. In protoplasts coinoculated with BMV RNAs 1 and 2, the resulting hybrid RNA3 was replicated by BMV trans-acting factors but was packaged in TMV coat protein to give rod-shaped particles rather than the usual BMV icosahedra. When the CcTMV encapsidation origin was suitably inserted in derivatives of BMV RNAs 1 and 2, these RNAs were also packaged in a ribonuclease-resistant form in protoplasts coinoculated with the hybrid RNA3 expressing TMV rather than BMV coat protein. Thus, despite the markedly divergent nature of BMV and TMV, replicating hybrids bearing characters derived from both parent viruses were produced. Such hybrid viruses could be of considerable value for studying specific steps in infection and for assigning functions to particular virus genes.

The complete primary structure of the cytoplasmically synthesized polypeptide IV from beef heart cytochrome oxidase was determined via isolation and sequencing of overlapping methionine, tryptophan, and arginine fragments. The protein consists of 147 amino acids (Mr 17153). It is characterized as a part of a membrane protein complex by a hydrophobic segment consisting of 19 residues. It is suggested that this segment contacts the lipids of the inner mitochondiral membrane. Additional specific contacts may result from pairwise formation of salt bridges between ionic groups of the protein and the phospholipids. The function of this component of the terminal oxidase is yet unknown.

Alpha-2-interferon (IFN) has demonstrable activity in advanced, relapsing, or refractory multiple myeloma. Because of the in vitro synergism between the IFNs and cytotoxic agents, we conducted a trial of 30 previously untreated patients with multiple myeloma utilizing various doses of alpha-2-IFN in combination with standard oral doses of melphalan and prednisone. The combination was well-tolerated without unusual or unexpected toxic effects. The limiting toxicity included dose-related myelosuppression, and alpha-2-IFN induced flu-like symptoms and fatigue. Response was seen in at least as many patients as would be expected with melphalan and prednisone alone. The maximal tolerated dose for a phase II-III trial was 5.0 X 10(6) IU/m2 of alpha-2-IFN in combination with standard doses of melphalan and prednisone. Future trials should utilize this dose of alpha-2-IFN with dose de-escalation according to tolerance.

An IgG1 monoclonal antibody, 31D8, that recognizes normal neutrophil (PMN) membranes, was used to study PMN from patients with chronic myelogenous leukemia (CML). Nineteen patients with Philadelphia chromosome positive CML were followed over a ten-month period and compared with 23 normals, six patients with leukemoid reactions, and eight patients with phagocytic cell defects. The percentage of PMN binding of 31D8 among normal subjects was variable about a normal distribution with an average of 95 +/- 2% of cells binding 31D8. In contrast, there were two groups of CML patients: in 14 patients 88 +/- 3% PMN bound 31D8 while in the remaining five patients only 6 +/- 6% PMN bound 31D8. PMN 31D8 binding was normal in the control patient groups. Control antibodies 7C3 (binds to PMN precursors) and OKM1 (binds to the CR3 (iC3b) receptor) bound normally to CML neutrophils. Functionally, CML cells had normal chemotaxis to several stimuli and normal superoxide generation to phorbol myristate acetate. However, superoxide production in response to fmet-leu-phe was significantly less in 31D8 negative CML PMN than both 31D8 positive CML PMN and normal PMN which contained 85% 31D8 positive and 15% 31D8 negative PMN. Clinically, 2 of 14 CML patients with 31D8 positive PMN were in blast crisis (one extramedullary) at the time of study and the other 12 patients remained clinically stable in the chronic phase during the ten months of study. In contrast, one of five patients with 31D8 negative PMN was in blast crisis at the time of study and all four of the remaining patients progressed to either the accelerated phase or blast crisis. Three of these patients died of their disease eight to ten months after their initial study. Thus, failure of CML cells to bind 31D8 may be useful for predicting which patients are likely to progress to the accelerated phase or blast crisis.

In its clinical presentation, malignant histiocytosis may mimic infections or hematologic neoplasms, and pathologically it may be mistaken for Hodgkin's disease, histiocytic lymphoma, or viral lymphadenitis. The case histories of three patients in whom malignant histiocytosis clinically and pathologically simulated granulomatous diseases are reported. Erythrophagocytosis was not present in the initial bone marrow aspirates from two of the patients. One patient was considered to hve sarcoidosis or Wegener's granulomatosis; the second patient, Weber-Christian disease, and the third patient, a granulomatous disease of infectious origin. Granulomas have been found in tissues of patients who have Hodgkin's disease, but have been found only rarely in association with malignant histocytosis. An explanation for the presence of granulomas in association with malignant histiocytosis is offered: they may represent a phase in the evolution of the disease.

An ostensibly normal 43-year-old man had intermittent fever, erythema multiforme, and leukopenia that evolved into fulminant hepatic and bone marrow necrosis. The cause of his illness was compatible with cytomegalovirus (CMV) infection since there was a fourfold increase in immunofluorescent antibody titer. This report suggests that CMV can produce a rapidly progressive and overwhelming infection in an apparently healthy adult.

A 73-year-old man with myelodysplastic syndrome developed during the course of his illness auto-immune hemolytic anemia. The association between auto-immune hemolysis and myeloproliferative disease is extremely rare. An even more unique finding is the nature of the antibody which demonstrated single specificity against the U antigen.

Waldenström's or primary macroglobulinaemia has rarely been documented in Black Africans. Six South African Negro patients with Waldenströms macroglobulinaemia were assessed and followed during a 10-year period from 1966 to 1976. The hyperviscosity syndrome was the presenting feature in four patients and one patient each presented with the nephrotic syndrome and a lacrimal mass respectively. On initial evaluation of the six patients, the serum IgM varied from 1.3 to 4.8 g% and in two patients cryoglobulinaemia was found. The patients received supportive treatment, chemotherapy, and when necessary, plasmaphoresis. One patient was lost to follow-up, one patient died 7 years after the onset of his illness, but the remaining four patients are alive 18 months to 5 years after presenting with their disease. Although the disease occurred in a younger age group (mean age 43 years) than in Caucasians it did not differ in clinical features or response to treatment from other parts of the world.

Essential to the management of the sick, low birth weight infant is maintenance of a neutral thermal environment by use of convection incubators and radiant warmers. Manipulation of the infant in preparation for transfusion and the transfusion of cold blood could theoretically lower the infant's body temperature, subsequently contribute to cold stress, and concomitantly increase metabolic demands and oxygen requirements. The authors evaluated different pretransfusion manipulations of syringe aliquots and bags of blood in an effort to provide a clinically acceptable product for transfusion to sick, very low birth weight infants.