Karyotypic evolution in Ph-positive chronic myeloid leukemia in relation to management and disease progression

In a prospective study of 32 patients with chronic myeloid leukemia the frequency of chromosome abnormalities in addition to the Philadelphia chromosome (Ph) increased when the disease progressed. Before metamorphosis, 10 patients (31%) had developed additional abnormalities. Such abnormalities were present in three of them at the time of diagnosis; in the other seven, they were detected late in the chronic phase. New clonal abnormalities heralded or accompanied a more malignant phase of the disorder, usually a blastic leukemia. During metamorphosis, 78% of the patients had additional abnormalities, which in 68% of these cases comprised at least one of +8, +22q- or i(17q). Clones with additional abnormalities disappeared in eight cases, either spontaneously or in association with cytostatic therapy during the chronic or blastic phase. Involvement of chromosome #8, usually in the form of a trisomy, was found in 7 of 12 patients treated with busulfan, but was not found in any of the 10 hydroxyurea-treated patients, of whom 8 were splenectomized early during the chronic phase. Cells from the spleen, obtained by fine needle aspiration or splenectomy were cytogenetically examined in 18 cases during the chronic phase, but abnormalities in addition to the Ph were noted in only one patient, who was examined in the late chronic phase. The same abnormalities were present in bone marrow cells of this patient.     

Induction of immune responsiveness in a genetically low-responsive tumor-host combination by chemical modification of the immunogen

Trinitrophenylated Moloney virus-induced YAC cells induced a higher cytotoxic antibody response and better protection against small tumor cell doses in syngeneic, low-responsive strain A mice than nonmodified YAC cells that had been inactivated by irradiation or mitomycin C treatment. The results indicated that genetically determined low responsiveness to a virally induced antigen can be overcome, at least to some extent, by coupling the immunizing cells to a strong immunogenic hapten.     

Acute pulmonary toxicity of inhaledβ-1,3-glucan and endotoxin

The number of inflammatory cells was studied in lung walls and airways after inhalation of endotoxin or -1,3-glucan. In the water unsoluble form, -1,3-glucan caused a delayed response in terms of a decrease in macrophages and lymphocytes in the lung wall, 1 to 7 days after exposure but no invasion of neutrophils into the airways. When solubilized in 0.02 N NaOH, the cell response was the same as that observed after exposure to endotoxin.     

Myeloperoxidase in human lung lavage

Bronchial wash and bronchoalveolar lavage were performed in 12 healthy subjects (five smokers), in order to elucidate whether or not material of neutrophil origin may be phagocytized by lung macrophages in vivo. Cells from different levels in the bronchial tree were obtained by sequential injection and subsequent aspiration of either four 50-ml or five 10-ml aliquots. Each aliquot was used for the determination of total and differential cell counts. The proportion of myeloperoxidase-positive alveolar macrophages was determined by specific immune histochemical staining. The percentage of myeloperoxidase-positive macrophages was highest (median 94.8%, range 37-98.5%) in the 10-ml aliquots and lowest in the last three 50-ml aliquots (median values 1-2.5%) (P less than 0.001). A significant correlation was obtained between the fraction of myeloperoxidase-positive macrophages and the percentage count of bronchoalveolar lavage neutrophils (r = 0.466, P less than 0.05). Furthermore, the cellular myeloperoxidase showed a significant inverse correlation (r = -0.46, P less than 0.05) to the viability of the bronchoalveolar lavage cells. Our findings are compatible with previous demonstrations in animals of neutrophil phagocytosis by lung macrophages and show that this phenomenon in particular occurs in the more proximal airways. The internalization of neutrophils or neutrophil components by airway macrophages may be an important scavenger mechanism for protection of the lung from the deleterious effects of activated neutrophils.     

Identification of a family with nonspecific mental retardation (MRX79) with the A140V mutation in the MECP2 gene: Is there a need for routine screening?

Mutations in the methyl-CpG-binding protein 2 (MECP2) cause Rett syndrome, a severe neurodevelopmental disorder occurring predominantly in females. Male patients with Rett syndrome are extremely rare, as the Rett-causing mutations in the MECP2 gene are usually lethal in hemizygous males. However, different mutations in the same gene were reported to cause mental retardation, both in sporadic non-syndromic males as well as in syndromic families with disease manifestation in carrier females. The majority of the reported MECP2 mutations in mentally retarded patients cause amino acid substitutions and, especially in isolated cases, discrimination between a disease-causing mutation and a rare polymorphism is not obvious and the significance of each individual variation should be verified. We mapped a new non-syndromic X-linked family (MRX79) to the chromosomal region Xq27.3-Xq28 and identified an A140V mutation in the MEPC2 gene in all patients with the disease haplotype. In addition to data published by others, this suggests that A140V is a recurrent mutation (and not a polymorphism) found in patients with X-linked mental retardation.     

Differences in adsorption of serum proteins and production of IL-1ra by human monocytes incubated in different tissue culture microtiter plates

In vitro cell culture models can be of great value in order to further analyze the regulatory mechanisms underlying the inappropriate function of the immune system in diseases such as autoimmunity and cancer. Cell culture conditions have to be well controlled in a way that they mirror the in vivo situation. The objective of this study was to compare tissue culture microtiter plates from different manufacturers with respect to their ability to support monokine production by human monocytes cultured in human serum. Tissue culture ware, made of polystyrene, undergoes treatment by the manufacturers to make the surface more suitable for culture of adherent cell populations. It is possible that quality differences in this treatment can lead to variations in protein binding properties and thereby influence the adherence and functional properties of monocytes. We measured spontaneous interleukin-1 receptor antagonist (IL-1ra) production by peripheral blood monocytes, cultured in human serum, in five different microtiter plates made for adherent cell culture. Culture in plates from two of the five manufacturers resulted in significantly lower amounts of secreted IL-1ra. IL-1ra release by human monocytes can be induced by adherent IgG cross-linking membrane receptors for the Fc part of IgG (FcgammaR). We found that reduced IL-1ra production coincided with a reduced capacity for binding of serum IgG in one case. Furthermore, this brand of microtiter plate also displayed the lowest level of adsorption of human albumin. We conclude that the protein adsorption properties of the plastic tissue culture ware have to be taken into consideration when assessing monokine production by human monocytes in vitro.     

Cytogenetic studies of bone marrow and extramedullary tissues and clinical course during metamorphosis of chronic myelocytic leukemia

Of 33 consecutive patients with chronic myelocytic leukemia, examined during metamorphosis, 82% showed chromosome abnormalities in addition to the Ph1. Aberrations most frequently encountered were +8 (39%), +22q - (30%), and i(17q) (18%). Translocations other than the Ph1 were observed in four cases and - Y clones in four cases. Discrepancies in the cytogenetic pattern between bone marrow and extramedullary tissues or blood were noted in a total of 15 patients. In six cases, transformation occurred in extramedullary organs at a time when it was not present in the marrow. In three cases the bone marrow transformation was preceded by a lymph node blastic infiltrate; in one case, by a skin infiltrate; and in one case, by a subdural blastoma. Clonal abnormalities additional to the Ph1 were identified in the tumor tissue from all these cases. Patients with primary extramedullary transformation tended to have a lower median age at onset of metamorphosis, shorter survival, and higher incidence of chromosome abnormalities than the cases without extramedullary involvement. Patients with only Ph1-positive cells and no other anomalies had a slightly longer duration of metamorphosis and longer total survival. Basophilia and thrombocytopenia were more marked in cases with i(17q) than in the rest of the series.     

Ectodermal dysplasias: Classification and organization by phenotype,genotype and molecular pathway

An international advisory group met at the National Institutes of Health in Bethesda, Maryland in 2017, to discuss a new classification system for the ectodermal dysplasias (EDs) that would integrate both clinical and molecular information. We propose the following, a working definition of the EDs building on previous classification systems and incorporating current approaches to diagnosis: EDs are genetic conditions affecting the development and/or homeostasis of two or more ectodermal derivatives, including hair, teeth, nails, and certain glands. Genetic variations in genes known to be associated with EDs that affect only one derivative of the ectoderm (attenuated phenotype) will be grouped as non‐syndromic traits of the causative gene (e.g., non‐syndromic hypodontia or missing teeth associated with pathogenic variants of EDA “ectodysplasin”). Information for categorization and cataloging includes the phenotypic features, Online Mendelian Inheritance in Man number, mode of inheritance, genetic alteration, major developmental pathways involved (e.g., EDA, WNT “wingless‐type,” TP63 “tumor protein p63”) or the components of complex molecular structures (e.g., connexins, keratins, cadherins).     

Lactic acidosis in thiamine deficiency

Two chronically ill patients with limited nutritional intake during several weeks developed prolonged lactic acidosis. As no other causes of hyperlactaemia could be identified, thiamine deficiency was suspected. Supplementation of 600 mg thiamine resulted in a rapid normalisation of serum lactate levels (in patient 1 from 10.9-2.4 mmol/l; in patient 2 from 11.8-2.0 mmol/l) and acid base status (patient 1: pH from 7.11-7.30, bicarbonate from 8.6-21.2 mmol/l; patient 2: pH from 7.24-7.46, bicarbonate from 16-28 mmol/l; before and after treatment, respectively). Thiamine deficiency was confirmed by the degree of stimulation of erythrocyte transketolase activation by adding thiamine pyrophosphate, evaluated before and after thiamine replacement therapy. Stimulation decreased in patient 1 from 170% to 17% and in patient 2 from 20% to 0%, respectively. In addition to the metabolic derangement right ventricular heart failure was confirmed by echocardiography in both patients and again this was rapidly reversible by thiamine supplementation. We conclude that in malnourished patients unexplained prolonged lactic acidosis may result from thiamine deficiency, which is rapidly reversible by thiamine replacement therapy.