Serum thrombopoietin levels in acute myeloid leukaemia.

To improve our understanding of the regulation of circulating platelet counts (PC) by thrombopoietin (TPO), we studied serum TPO levels and PC before and after myelosuppressive chemotherapy in 12 patients with acute myeloid leukaemia (AML). Serum TPO levels were measured by the quantitative sandwich enzyme-linked immunosorbent assay (Quantikine, RD Systems). At the start of the induction chemotherapy, the patients had a median serum TPO level of 199 pg/ml (range 120-2,150 pg/ml), while 10 to 12 days after the end of chemotherapy, their TPO levels were substantially increased, the median value being 1,907 pg/ml (range 1,049-4,194 pg/ml). The correlation between PC and TPO was statistically significant prior to chemotherapy (p < 0.03) and insignificant after chemotherapy. As a result of chemotherapy, the patients developed aplasia; after the administration of platelet transfusions, their median PC increased to 21 x 10(9)/l (range 5-55 x 10(9)/l), while the median TPO value decreased by 300 pg/ml (range 11-1,125 pg/ml). Our results suggest that platelet mass directly regulates serum TPO levels in acute leukaemia patients prior to chemotherapy and after the administration of platelet transfusions. Serum TPO levels may also be influenced by the cytokine response during complicating infections in patients with chemotherapy-induced cytopenia.

The behavioral detection of binary mixtures of amino acids and their individual components by catfish.

The question of whether a binary mixture of amino acids is detected by fish as a unique odor or whether the qualities of the individual components are retained within the mixture was investigated in channel (Ictalurus punctatus) and brown bullhead (Ameiurus nebulosus) catfish, species that are highly similar in their olfactory receptor and behavioral responses to amino acid odorants. Catfish respond with greater appetitive food-searching (swimming) behavior to amino-acid-conditioned olfactory stimuli than to non-conditioned amino acids. In the present study, appetitive food-searching behavior was measured by counting the number of turns of the fish greater than 90 degrees within 90 s of stimulus onset and, in some tests, by video tracking. The two methods yielded highly correlated results. Channel catfish conditioned to a binary mixture composed of equimolar amino acids responded with searching behavior to the amino acid that produced the larger-amplitude electro-olfactogram (EOG) response as they did to the conditioned stimulus. In further studies, bullhead catfish were conditioned either to a binary mixture or to a single amino acid and tested to determine whether a binary mixture was detected as the component evoking the larger EOG response. In all initial tests (trials 1-3), the more stimulatory component of a binary mixture was not discriminated from the binary mixture; however, the less stimulatory component and all other amino acids tested were discriminated from the mixture. By increasing the concentration of the originally less potent component in a binary mixture, making it the more stimulatory compound, it was now detected as not significantly different from the binary mixture; however, the original more potent component (i.e. now the less potent stimulus) was detected as significantly different from the mixture. However, with 5-10 additional discrimination training trials, the less stimulatory component in a binary mixture influenced the perception of the binary mixture because the binary mixture was no longer detected only as its more stimulatory component. The data suggest that a two-step learning process occurs within the olfactory bulb and possibly higher-order telencephalic nuclei.

Learned olfactory discrimination of amino acids and their binary mixtures in bullhead catfish (Ameiurus nebulosus).

The question of whether bullhead catfish can discriminate binary mixtures of amino acids from the individual components of the mixture was investigated. Two groups of catfish were conditioned to different binary mixtures of L-norvaline (NVAL) and L-leucine (LEU). The concentrations of the amino acids in the conditioned mixtures were adjusted so that in different mixtures either NVAL or LEU was the more stimulatory component. Bullhead catfish were unable to discriminate the more stimulatory components, but were able to discriminate the less stimulatory components and other amino acids from the conditioned mixtures. The third group of bullhead catfish was conditioned to L-proline (PRO) and the responses to different mixtures of PRO and NVAL were subsequently evaluated. Behavioral and electrophysiological (EOG) experiments indicated that the difference in relative stimulatory effectiveness levels between NVAL and PRO is > 30,000 times. For subsequent tests, the concentrations of PRO and NVAL were adjusted to form binary mixtures in which PRO and NVAL, respectively, were the more stimulatory components. Bullhead catfish conditioned to PRO discriminated the mixture if NVAL was the more stimulatory component, but did not discriminate PRO from the mixture if PRO was the more stimulatory component. These results suggest that binary mixtures of amino acids are initially perceived as the more stimulatory components of the mixture.

Monitoring the remission induction therapy of acute nonlymphoblastic leukemia by bone marrow cell culture criteria.

In 31 cases of acute nonlymphoblastic leukemia, bone marrow cells were serially cultured in semi-solid agar during the remission induction therapy. A normal in vitro cell growth pattern returned in 15 out of 22 patients up to 77 days before a complete remission was established by clinical and hematological criteria. In 6 cases the return of normal colonies coincided with clinical and hematological evidence of a complete remission. Nine patients failed to attain a remission and died from complications of bone marrow aplasia. Only one had a normal number of colonies and a normal cluster/colony ratio in cultures prepared 11 days after the completion of the first course of chemotherapy. At this time, his platelet count increased to normal level, possibly indicating a developing remission. Bone marrow cell culture criteria are useful in monitoring the remission induction therapy in patients with acute nonlymphoblastic leukemia. An early return of normal in vitro cell growth pattern suggests an approaching remission, which may be achieved several weeks later.

[Immunologic function of the tonsils in relation to immune competent T and B cells in children]. / Immunologische Funktion der Tonsillen in bezug auf immun-kompetente T- und B-Zellen bei Kindern.

The authors introduced a E and EAC rosette-forming cell technique with semiquantitative evaluation of T and B lymphocytes in the peripheral blood of 56 healthy persons of both sexes and of different ages. The percentages of T and B lymphocytes in the peripheral blood and tonsils of 31 children was also calculated. The percentage of rosette forming cells in E and EAC suspensions appeared to be independent of age and sex. The percentage of T lymphocytes in the peripheral blood is significantly higher than in the tonsils, whereas the percentage of B lymphocytes is significantly higher in the tonsils than in the peripheral blood. The percentage of T lymphocytes was found to be significantly higher in hypertrophic as the mean percentage of T lymphocytes in tonsils of 31 children. Also in tonsils with adhesions there was a statistically significant higher percentage of EAC rosettes than in tonsils free of adhesions.

T and B lymphocyte rosettes in tonsils of atopic and non-atopic children.

This investigation was carried out to determine the immunological function of the human tonsils, especially the role of lymphocytes of atopic and non-atopic children. An E- and EAC-rosette forming technique is introduced, with semiquantitative evaluation of T and B lymphocytes in the peripheral blood of 56 normal subjects, 28 atopic and 5 non-atopic children of both sexes and different ages. The percentage of T and B lymphocytes in removed palatine tonsils in 28 atopic and 5 non-atopic children was calculated. The percentage of rosette-forming cells in E and EAC suspensions appeared to be independent of age and sex. The percentage of T lymphocytes in peripheral blood was significantly higher than in the palatine tonsils, whereas the percentage of B lymphocytes was significantly higher in the tonsils of atopic and non-atopic children than in the peripheral blood. The mean percentage of B lymphocytes in the tonsils of atopic children was significantly higher than in non-atopic children. The percentage of B lymphocytes was found to be significantly higher in hypertrophic than in small tonsils. Also, in the tonsils with adhesions there was a statistically significantly higher percentage of EAC rosettes than in the tonsils free of adhesions. The percentage of T lymphocytes was statistically significantly higher in the small tonsils.

Immunological function of tonsils in atopic and nonatopic children, with special reference to E- and EAC-binding lymphocytes.

This investigation was carried out to determine the immunological function of the human tonsils, especially the role of lymphocytes of the atopic and nonatopic children. Authors introduced E- and EAC-rosettes forming technique with semi-quantitative evaluation of T and B lymphocytes in peripheral blood of 56 normal subjects, 28 atopic and 5 nonaptoic children of both sexes and different age. The percentage of T and B lymphocytes in removed palatine tonsils in 28 atopic and 5 nonatopic children was calculated. The percentage of rosettes forming cells in E and EAC suspensions appeared to be independent of age and sex. The percentage of T lymphocytes in peripheral blood is significantly higher than in the palatine tonsils whereas the percentage of B lymphocytes is significantly higher in the tonsils of atopic and nonatopic children than in the peripheral blood. The mean percentage of B lymphocytes in the tonsils of atopic children is significantly higher than in nonatopic children. The percentage of B lymphocytes was found to be significantly higher in hypertrophic than in small tonsils. Also, in the tonsils with adhesions there was a statistically significant higher percentage of EAC rosettes than in the tonsils free of adhesions. The percentage of T lymphocytes is statistically significant higher in the small tonsils.