Complex Ph1 translocation in chronic myeloid leukemia

This report describes a new case of chronic myeloid leukemia with an unusual Philadelphia chromosome translocation involving chromosomes No. 4,9, and 22; t(4,9,22) (q31;q34;q11).     

Chronic myelogenous leukemia (CML) with translocation (8;22): a new variant

A case of chronic myelogenous leukemia (CML) in a young woman with a new variant Ph1-translocation--i.e., t(8;22) (q24;q12)--is described. The clinical and biological aspects of the disease did not seem to differ from those of the usual cases of CML.     

Cytogenetic studies in a case of T-cell prolymphocytic leukemia

The authors describe cytogenetic aberrations observed in a case of T prolymphocytic leukemia. C11 deletion (q14) B5 deletion (pter), D14q⁺, E20 trisomy, and two markers are the main anomalies of the complement.     

Functioning microvillous adenoma of the parathyroid gland containing nuclear pores and annulate lamellae

The cytoplasmic membranes of chief cells in parathyroid adenomas from patients with primary hyperparathyroidism associated with either severe or mild hypercalcemia were examined in an attempt to correlate ultrastructural changes and biochemical findings. In the case involving the highest serum calcium level (17.5 mg/dl), the cytoplasmic membrane exhibited numerous long cytoplasmic processes (microvilli) that extended into wide intercellular spaces. In this respect this tumor, associated with severe hypercalcemia, was different from previously described parathyroid adenomas and from the adenomas of the present study that were associated with mild hypercalcemia (12.4 +/- 0.5 mg/dl); the active chief cells of the latter were characterized by a relatively straight plasmalemma with interdigitations and narrow intercellular spaces. Also of interest in the case involving severe hypercalcemia was the presence of numerous nuclear pores and annulate lamellae as well as an inconspicuous Golgi apparatus. These ultrastructural features would seem to indicate the existence of further morphologic parameters for the evaluation of chief cell activity.     

Isolation and culture of Methanobrevibacter smithii by co-culture with hydrogen-producing bacteria on agar plates

ObjectivesMethanogenic Archaea are considered as extremely oxygen-sensitive organisms, and their culture is fastidious, requiring specific equipment. We report here conditions allowing the cultivation of Methanobrevibacter smithii in an anaerobic chamber without the addition of hydrogen.MethodsWe first enriched the stool sample in an anaerobic liquid medium. To cultivate M. smithii with Bacteroides thetaiotaomicron and other hydrogen-producing bacteria on solid medium in an anaerobic chamber, we divided the agar plates into two compartments and seeded each strain on each compartment. Methane production was assessed by gas chromatography, and the growing colonies were authenticated by MALDI-TOF MS.ResultsWe successfully cultured M. smithii from a liquid culture medium inoculated with stool collected from a healthy donor in an anaerobic chamber. The isolation in pure culture permitted successful culture on agar medium by our performing a co-culture with B. thetaiotaomicron. We also successfully tested the co-cultivation of M. smithii with other known hydrogen-producing bacteria. Gas chromatographic tests showed that these strains produced hydrogen in different amounts. Agar colonies of methanogens were obtained by co-culture with these bacteria, and methane production was detected.ConclusionsWe propose a new approach to isolate and cultivate new strains of M. smithii by using a co-culture–based technique that can facilitate and make available the isolation of new methanogenic Archaea strains in clinical microbiology laboratories.     

Genetic diversity and deletion of Plasmodium falciparum histidine-rich protein 2 and 3: a threat to diagnosis of P. falciparum malaria

BackgroundPfHRP2-based rapid diagnostic tests (RDTs), based on the recognition of the Plasmodium falciparum histidine-rich protein 2, are currently the most used tests in malaria detection. Most of the antibodies used in RDTs also detect PfHRP3. However, false-negative results were reported. Significant variation in the pfhrp2 gene could lead to the expression of a modified protein that would no longer be recognized by the antibodies used in PfHRP2-based RDTs. Additionally, parasites lacking the PfHRP2 do not express the protein and are, therefore, not identifiable.AimsThis review aims to assess the pfhrp2 and pfhrp3 genetic variation or the prevalence of gene deletion in areas where malaria is endemic and describe its implications on RDT use.SourcesPublications of interest were identified using PubMed, Google Scholar and Google.ContentMore than 18 types of amino acid repeats were identified from the PfHRP2 sequences. Sequencing analysis revealed high-level genetic variation in the pfhrp2 and pfhrp3 genes (>90% of variation in Madagascar, Nigeria or Senegal) both within and between countries. However, genetic variation of PfHRP2 and PfHRP3 does not seem to be a major cause of false-negative results. The countries that showed the highest proportions of pfhrp2-negative parasites were Peru (20%–100%) and Guyana (41%) in South America, Ghana (36%) and Rwanda (23%) in Africa. High prevalence of pfhrp2 deletion causes a high rate of false-negatives results.ImplicationsPresence of parasites lacking the pfhrp2 gene may pose a major threat to malaria control programmes because P. falciparum-infected individuals are not diagnosed and properly treated.     

Voluntary heart rate lowering following a cardiovascular arousing task

The purpose of the research was to evaluate the effect of feedback-assisted voluntary control to lower heart rate (HR), following a non-somatic mediated task designed to induce cardio-vascular activation. Twenty-seven male subjects participated in this study and were randomly divided into three groups. All subjects were submitted to an arousing mental arithmetic task for a 1 min period, followed either by a feedback-assisted HR lowering task (FG), by an unassisted HR lowering task (ICG), or by a relaxation period (RCG). During this period (2 min duration), ICG and RCG subjects were required, as a help for HR deceleration or relaxation, to track visually a sweeping line similar in form to the continuous analogue feedback of the FG subjects. This sequence, interspaced by a 1 min rest period, was repeated 10 times. Results showed that the mental arithmetic task was effective in producing consistent and repetitive HR acceleration. All three groups showed significative HR lowering during the following voluntary HR control or relaxation period. However, there was no difference in the speed or depth of HR lowering. It appeared that continuous-analogue feedback was not more effective than instructions to relax to assist HR return to lower levels.     

Selective changes in the metabolism of biogenic amines after successive discrimination training in cats

This study was undertaken to show whether in cats successive discrimination training is accompanied by changes in monoamine concentrations and turnover rates. Training was continued until animals showed significantly correct performance. Two control groups were used: one non-manipulated baseline group, and one manipulated non-learning group which was put through the experimental procedure but did not learn the discrimination task. Noradrenaline and serotonin levels were determined in brain tissue from several regions, and dopamine β-hydroxylase activity was also measured. No difference whatever in the levels of biogenic amines or of enzyme activity was observed between baseline and manipulated controls. Learning animals showed increased levels of serotonin in the neostriatum and the mesencephalon (excluding the raphe nuclei), diminished noradrenaline levels in the piriform lobe, mesencephalon and thalamus and increased noradrenaline in the neostriatum. The falls in noradrenaline levels were mirrored by increased dopamine β-hydroxylase activity in the same regions.Learning animals attained ‘criterion’ after successfully overcoming a tenacious position habit: the biochemical changes observed could therefore be related to suppression of the incorrect strategy, a crucial element in the learning of the successive discrimination. These results contrast markedly with earlier work where in a different situation (delayed-response learning). changes in monoaminergic functions were found in quite different anatomical structures.     

Cytogenetic study of 88 cases of refractory anemia

Data obtained on 88 patients with refractory anemia or preleukemia, without previous cytotoxic treatment, showed medullar chromosomal abnormalities in 32%. In 45% of the cases, the disease had progressed to acute nonlymphocytic leukemia. A high frequency of acute transformation (78%) was observed in patients with abnormal clones. These results are different from those of the Second International Workshop on chromosomes in Leukemia. The discrepancies may be related to the difference between the cases selected for submission to the workshop and those of this study. Serial studies on 28 patients with abnormal karyotypes showed that two different populations of patients were investigated: one with a terminal smoldering phase of leukemia and the other with true preleukemic disease. In the latter group, no predictive karyotype evolution was seen.     

Chromosome studies in polycythemia vera patients

One hundred thirty-five polycythemia vera (PV) patients (30 untreated by chemotherapy and 105 treated) were studied cytogentically. The incidence of clonal chromosomal abnormalities was 20.7% (28 patients in nonleukemic phase). The incidence of 20q? was 3.7% (5 patients). The presence of cytogenetically abnormal clones did not allow prediction of the evolution of the disease. In a few cases, abnormal clones disappeared at the time of later studies. Although nonrandom, the majority of clonal chromosomal abnormalities are believed to be secondary events in PV patients.     

Cytogenetic studies on acute nonlymphocytic leukemias following polycythemia vera

Chromosome studies were performed on 15 patients suffering from acute nonlymphocytic leukemia (ANLL) and in one patient in a preleukemic state following polycythemia vera (PV). Clonal chromosome abnormalities that were present in all cases were clearly nonrandom and involved chromosomes #1, #5, #7, #8, #9, #11, and #21. A subdivision of ANLL into two categories occurring in the course of PV is proposed from the clinical, hematologic, and cytogenetic data: one resembling de novo ANLL with rapid initial evolution, easy classification into one group of the FAB nomenclature, and simple chromosome abnormalities; the other resembling induced leukemia, often with more progressive initial evolution, difficulty or impossibility of classification into one group of the FAB nomenclature, and complex chromosome abnormalities. The consequences for the commitment level of progenitor cell from which the leukemic clones originate are discussed.     

The role of T-agglutinin in the disappearance of erythrocytes artificially aged by desialylation

The chance discovery of two mouse strains, one with and one without a high presence of serum T-agglutinin, permitted the investigation of the role of this antibody in the disappearance of desialylated erythrocytes, which may be regarded as a model for ageing. The proportional relationship between the quantity of sialic acid removed and the diminution of half-life is not affected by the presence or absence of T-agglutinin. Opsonization by T-agglutinin would therefore appear to be an improbable mechanism. Other possible theories are discussed.     

Variant translocation in Burkitt's lymphoma: 8;22 translocation in a French patient with an Epstein-Barr virus-associated tumor

A variant translocation t(8;22)(q23;q11) has been found in tumor cells from a 19-year-old white man with an Epstein-Barr virus-associated Burkitt's lymphoma (BL). The tumor, which appeared 2 years after the patient had infectious mononucleosis, bore histopathological features characteristic of BL, although only the lymph nodes in the cervical region were involved. This case and some other recent cytogenetic observations of nonendemic BL emphasize the importance of chromosome #8 rearrangement in this B-cell-type lymphoma.