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Objective: We have previously described associations between an allele of the interleukin-1 receptor antagonist gene (IL1RN) and several inflammatory diseases. In this study we tested the IL1RN gene as a possible marker in patients with systemic lupus erythematosus (SLE)., Methods: Eighty-one SLE patients and 261 ethnically matched control subjects were genotyped by polymerase chain reaction., Results: We found an increase in both frequency and carriage rate of IL1RN*2 in the SLE group. This association strengthened with extensive disease and particularly with the presence of photosensitivity and discoid skin lesions., Conclusion: We describe a novel association between IL1RN*2 and SLE. Carriage of the allele seems to influence severity rather than susceptibility to SLE. We postulate that the association of this polymorphism with disease severity is a widespread feature of common inflammatory and autoimmune diseases.

One of the most potent pro-inflammatory mediators is the early-acting cytokine interleukin-1. Its actions are regulated by a structurally related anti-inflammatory cytokine known as the interleukin-1 receptor antagonist. We have previously characterized a DNA polymorphism in this gene (IL-1rn) and have found associations between allele 2 and several chronic inflammatory diseases. In the present study, we tested the frequency of allele 2 of the IL-1rn gene in 90 patients with alopecia areata compared with 261 healthy controls. There was a significant association between allele 2 of the polymorphism and the severity of alopecia areata. The frequency of allele 2 increased from 24.1% in the control population to 25.9% in patchy alopecia areata, 36.1% in alopecia totalis, and 47.2% in alopecia universalis (p = 0.005). This severity association is similar to that found in other epithelial-related diseases, including inflammatory bowel disease, lichen sclerosus, and systemic lupus erythematosus.

A 13-month-old girl presented with red finger marks on both shoulders thought initially to be secondary to child abuse. The appearance of the marks was not typical of bruising of the stated age and there were no social concerns or other medical features of child abuse. Direct questioning revealed that the mother had been gardening on a sunny day and had picked the child up prior to the appearance of the marks. The marks are thought to represent a phytophotodermatitis. Many paediatric skin conditions can mimic child abuse. Recognition of this further possibility will prevent avoidable errors of diagnosis.

Proton nuclear magnetic resonance spectra of ferricytochrome cd1 from the denitrifying bacterium Pseudomonas aeruginosa have been obtained. The normal 0-10-ppm chemical shift range shows many overlapping and nonresolvable peaks, as would be expected for a dimeric protein of molecular weight approximately 120,000. In the downfield region between 10 and 50 ppm, and in the upfield region between 0 and -20 ppm, resolvable resonances corresponding to a small number of protons are observed. The temperature and pH behavior of these resonances have been examined. For some of the resolved resonances, the pH behavior of chemical shifts and intensities indicates that the oxidized form of the enzyme undergoes a structural transition with a pK of 5.8 +/- 0.3. On the basis of several lines of evidence, some assignments are proposed in which resolvable resonances are assigned as originating from either the heme c or the heme d1 prosthetic groups of the enzyme.

Proton nuclear magnetic resonance spectra are reported for cytochrome cd1 from Pseudomonas aeruginosa (ATCC 19429) in several forms including complexes of the ferricytochrome with cyanide, azide, and fluoride, a quasi-apo form in which the noncovalently associated heme d1 has been removed but the covalently bound heme c is retained, and the reduced state of both native and the quasi-apo forms. Comparisons are made to the previously reported spectrum of ferricytochrome cd1. The following points are made. The spectra of the azide and fluoride complexes and the ferric quasi-apo form show perturbation of resonances assignable to the site of heme d1, and leave relatively unperturbed resonances assignable to the site of heme c. The heme d1 associated resonances are at 46.0, 35.4, 23.3, 17.5, -2.9, and 16 ppm, and the heme c associated resonances are at 42.0, 33.7, 15.0, 13.9, -7.5, -14, and -33 ppm in native ferricytochrome cd1. The similarity of the hyperfine resonances of the ferric quasi-apo from to the heme c resonances of intact ferricytochrome cd1 is evidence that removal of heme d1 leaves the heme c binding site relatively unaltered. Linewidths and relaxation times suggest that the relaxation times of the unpaired electron spins of the ferric hemes c and d1 are on the same order of magnitude. Although it is paramagnetic, ferrocytochrome cd1 does not demonstrate an experimentally detectable hyperfine shifted spectrum under present conditions. Possible reasons for this are discussed. The presence of a narrow resonance at -2.8 ppm in both ferrocytochrome cd1 and the reduced state of the quasi-apo form suggests that methionine may be a ligand to heme c.

A complete hematologic remission was achieved in a patient with therapy-related preleukemia and transfusion-dependent pancytopenia after treatment with recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF). The patient remained in remission for nearly 1 year despite the discontinuation of GM-CSF treatment. Several lines of evidence suggest that normal hematopoiesis was restored after GM-CSF treatment. First, the cytogenetic anomaly, which was present before GM-CSF, completely disappeared after three cycles of treatment. Cytogenetic conversion was documented by conventional karyotypic evaluation of mitotic bone marrow cell preparations as well as by premature chromosome condensation analysis of the nonmitotic cells of bone marrow and peripheral blood. Second, the growth pattern and cycle status of bone marrow granulocyte-macrophage (CFU-GM) and erythroid (BFU-E) progenitor cells were found to be normal during remission. Third, X chromosome-linked restriction fragment length polymorphism-methylation analysis of DNA from mononuclear cells (greater than 80% lymphocytes) and mature myeloid elements showed a polyclonal pattern. These findings suggest that restoration of hematopoiesis in this patient after GM-CSF treatment may have resulted from suppression of the abnormal clone and a selective growth advantage of normal elements.

Nitrogen-15 nuclear magnetic resonance (15N NMR) spectroscopy at 30.4 MHz was employed to determine the interaction of the substrate nitrite (97.2% enriched) with bacterial nitrite reductase, denoted cytochrome cd1, from Pseudomonas aeruginosa. The addition of ferric enzyme to nitrite did not alter the chemical shift of the bulk nitrite resonance, nor was it possible to observe a new resonance from a hypothetical bound form. However, the spin-lattice relaxation time (T1) was lowered from 13.2 to 2.7 s, and the spin-spin relaxation time (T2) was halved. Values of T1 were measured by progressive saturation and values of T2 by line widths. Control experiments involving ferric cytochrome c and metmyoglobin demonstrated that the perturbations did not arise from the bulk paramagnetic properties of the protein solutions. Variable enzyme/substrate ratios were measured to assess the strength of interaction. The most reasonable model consistent with the data proposes a weak association between nitrite and ferric reductase with a value of 1.3 M-1 for the association constant.

Cytochrome c-554 from the bacterium Alcaligenes faecalis (ATCC 8750) is a respiratory electron-transport protein homologous to other members of the cytochrome c family. Its structure has been studied by 1H NMR spectroscopy in both the ferric and ferrous states. The ferric spectrum is characterized by downfield hyperfine-shifted heme methyl resonances at 46.25, 43.60, 38.40, and 36.73 ppm (25 degrees C, pH 7.1). Chemical shifts of these resonances change with temperature opposite to expectations derived from Curie's law. The pH behavior of the hyperfine-shifted resonances titrates with a pK of 6.3 that has been interpreted as due to ionization of a heme propionate. In the ferrous state, heme methyl, meso, and thioether bridge resonances have been observed and assigned. All aromatic proteins have been assigned according to the side chain of origin, and the structural environment about the sole tryptophan residue has been examined. The electron-transfer rate between ferric and ferrous forms has been estimated to be on the order of 3 X 10(8) M-1 s-1, which is the largest such self-exchange rate yet observed for a cytochrome.

The magnetic susceptibilities of cytochrome cd1 from Pseudomonas aeruginosa (American Type Culture Collection 19429) have been measured by a nuclear magnetic resonance technique. In the oxidized form both heme c and heme d1 are in the low-spin state with an average magnetic moment of 2.6 Bohr magnetons. At 25 degrees C and pH 8.0, the ascorbate-reduced cytochrome contains one low-spin and one high-spin heme per subunit. Based on previous reports in the literature, the high-spin ferrous heme has been assigned to the heme d1 group. At pH 8.0 the ascorbate-reduced heme d1 has a magnetic moment of 5.3 Bohr magnetons. This value decreases to 4.9 at pH 5.5, but is still indicative of a high-spin ferrous system. The paramagnetic susceptibility of the ferricytochrome demonstrated a temperature dependence consistent with Curie's law, but the ferrocytochrome showed an increase in paramagnetic susceptibility with increasing temperature.

Prognostic factors were identified from the histories of 194 patients diagnosed as having low infiltrate leukemia (LIL) between 1973 and 1981, when the policy was to delay treatment until there was evidence of progressive disease or life-threatening morbidity. Their median age was 59 yr; 63% were male; 30 had had a malignant disease previously. Presenting symptoms included anemia, 82%; infections, 15%; and hemorrhage, 16%. The group's median survival was 42 weeks, with high marrow cellularity and percentage of blasts, impairment of bone marrow, liver or renal function, age over 65 yr and performance status less than 80% associated with poorer survival. Cytogenetic changes associated with poor survival included loss of chromosome 5 or 7, additional chromosome 8, karyotypic instability, and presence of 100% abnormal metaphases. A regression model including terms for blood and bone marrow features, and age at hospital admission was able to stratify patients into prognostic groups in the same population and in an independent population admitted prior to 1973. Further prospective testing of the model is required. Twenty-six of the 78 patients who were eventually treated with combination chemotherapy achieved complete remission. The presence of Auer rods, diagnosis of acute leukemia or refractory anemia with excess blasts, rapid increase in marrow infiltrate and favorable cytogenetic karyotype were associated with response. Delaying treatment in all patients was found to have improved only modestly the survival of patients with LIL.

The 1H NMR spectra of ferri- and ferro-cytochrome c-550 from Paracoccus denitrificans (ATCC 13543) have been investigated at 300 MHz. The ferri-cytochrome c-550 shows hyperfine-shifted heme methyl resonances at 29.90, 29.10, 16.70, and 12.95 ppm and a ligand methionyl methyl resonance at -15.80 ppm (pH 8 and 23 degrees C). Four pH-linked structural transitions were detected in spectra taken as a function of pH. The transitions have been interpreted as loss of the histidine heme ligand (pK less than or equal to 3), ionization of a buried heme propionate (pK = 6.3 +/- 0.2), displacement of the methionine heme ligand by a lysyl amino group (pK congruent to 10.5), and loss of the lysyl ligand (pK greater than or equal to 11.3). The temperature behavior of hyperfine-shifted resonances was determined. Two heme methyl resonances (at 16.70 and 12.95 ppm) showed downfield hyperfine shifts with increasing temperature. The cyanoferricytochrome had methyl resonances at 23.3, 20.1, and 19.4 ppm. NMR spectroscopy did not detect the formation of a complex with azide. The second-order rate constant for electron transfer between ferric and ferrous forms was determined to be 1.6 X 10(4) M-1 s-1. Heme proton resonances were assigned in both oxidation states by cross-saturation and nuclear Overhauser enhancement experiments. Spin-coupling patterns in the aromatic region of the ferro-cytochrome spectrum were investigated.

Normal murine bone marrow was incubated with medium conditioned by liver cells from human fetuses of 11-17 weeks gestational age. This treatment increased the proportion of murine haemopoietic stem cells (CFU-S) which were synthesizing DNA from less than 10% to more than 30%. The human fetal liver cell supernatants were fractionated using Amicon filters to obtain nominal molecular weight ranges of 10-30,000, 30-50,000 and 50-100,000 daltons. The stimulator was present only in the 30-50,000 dalton fraction. When human fetal liver cells were separated by adherence to plastic, medium conditioned by the adherent, but not the non-adherent, cells produced the stimulator. A population of non-cycling GM-CFC was not switched into cycle during incubation with this CFU-S proliferation stimulator. Human fetal livers of all gestational ages tested contain a specific stimulator of CFU-S proliferation. This appears to have properties similar to that demonstrated in murine fetal liver and regenerating murine bone marrow. Human and murine haemopoietic stem cell proliferation may therefore be regulated by similar mechanisms.

A high molecular-weight c-type cytochrome was purified from Alcaligenes faecalis ATCC 8750. Its weight was 40,000 daltons by sodium dodecyl sulfate-gel electrophoresis. Heme content was determined to be one heme per 40,000 daltons. Proton nuclear magnetic resonance-NMR-spectroscopy determined that the ferrous form is low spin. The detection of a methyl resonance at -3 ppm in the ferrous form indicated that methionine is a heme ligand in this state. The NMR spectrum of the ferric form at pH 7.2 revealed hyperfine shifted methyl resonances at 67.79, 63.17, 57.71, and 50.46 ppm. The large downfield shifts observed are indicative of high spin character. The ferric spectrum was pH-sensitive, indicating two pH-linked structural transitions with estimated pKs at 6.0 and 10.5. The first is interpreted as due to the ionization of a heme propionate. The second is interpreted as the acquisition of a strong field ligand and the subsequent conversion to a low spin ferric form. The ferricytochrome did not form complexes with cyanide, azide, or fluoride at pH 5.2 or 7.9.