Leucostasis, an underestimated cause of death in leukaemia

Massive sludging of leukaemic cells in blood vessels is a frequent and often lethal complication of leukaemia. In a retrospective clinicopathological study on the causes of death in 52 patients with acute myeloid leukaemia and myeloproliferative disease, pulmonary leucostasis was found in 40% of the patients. In many of these patients the vessels of the heart, brain and testes were also involved. In search for signs and symptoms specific for leucostasis, the clinical records of the 21 patients with leucostasis (the study group) were compared to those of 20 patients without leucostasis (the control group). Dysfunction of the organs most affected by leucostasis, namely lungs, heart and brain, was found more often in the study group than in the controls, but the combination of unexplained fever with cardiopulmonary and/or central nervous system failure occurred almost exclusively and in half of the patients with leucostasis. Leucostasis occurs predominantly, but not exclusively, in patients with high leucocyte counts, and especially, but again not exclusively, when the leucocyte counts rise sharply.     

Initial decomposition ofNymphoides peltata (Gmel.) O. Kuntze (Menyanthaceae), as studied by the leaf-marking method

Summary In this paper the leaf-marking method as used for the study of the development and initial decomposition of floating leaves is described and the reliability of the various measurements is tested and/or discussed. Some general results obtained withNymphoides peltata (Gmel.) O. Kuntze in tanks and in the field are presented and crltically discussed. Autolysis followed by microbial decay was in all cases the most important factor by which leaves disintegrated. In the field plots animals were responsible for the disappearance of 22% of the total leaf area produced during a growth season. This is, however, the combined effect of consumption and damage succeeded by microbial decay. Real grazing can be estimated to be no more than 10% of the production of floating leaves. Fungi can have an important role in initial decomposition, especially after the flowering period, as is demonstrated forSeptoria villarsiae Desm. All damage types show temporal and, in the case of animals, also spatial distribution patterns.     

Cytokinetic analysis of lung cancer by bromodeoxyuridine labeling of cytology specimens

Recent flow cytometric (FCM) studies have indicated the prognostic value of S-phase cells (SPF) in lung cancer. More refined cytokinetic analysis can be obtained by dual-parameter FCM, labeling S-phase cells with 5-bromodeoxyuridine (BrdUrd), which can be detected using a monoclonal antibody (MoAb) to BrdUrd. Tumor cells obtained through bronchoscopic brush were incubated for 1 hr in RPMI 1640 medium with 10% fetal calf serum and 10 microM BrdUrd. After fixation in ethanol, pepsin treatment, and DNA denaturation, the nuclei were stained with anti-BrdUrd MoAb and propidium iodide. From 14 of 20 patients, sufficient material was obtained (three adenocarcinoma and seven squamous cell, one giant cell, and three small cell carcinoma). The measured SPF ranged from 5.2% to 26%. The labeling index (LI), calculated as the ratio of the number of BrdUrd-labeled cells to the total number of aneuploid cells, or diploid cells in the case of a diploid tumor, ranged from 1.2% to 16.7%; LI and SPF correlated significantly (r = 0.69). In this study, we have demonstrated the feasibility of determining the actively DNA-synthesizing cells on brush material from lung cancer cells. In addition, some extra information can be obtained about the SPF population, including the fraction of unlabeled SPF, which could be of prognostic significance.     

Electron microscopy of the germ cells and the ovarian wall in Xiphinema (Nematoda)

The ovary of Xiphinema theresiae is studied ultrastructurally. It consists of two cell types, the ovarian epithelial cells and the germ cells. The ovarian epithelial cells form a thin layer around the germ cells. Their nuclei are located in between the germ cells. At some sites, processes of the ovarian epithelial cells migrate inward and form a central cytoplasmic mass. The germ cells have a large lobated nucleus, with an eccentric nucleolus, and are considered to represent young previtellogenic oocytes. In contact with the central cytoplasmic mass, the germ cells develop two membrane derived features, the villi and the small coated bulges, which most probably play a role in transport.     

Evidence for the involvement of a SchistoFLRF-amide-like peptide in the neural control of locust oviduct

Summary The presence of a SchistoFLRFamide-like peptide associated with the oviducts of Locusta migratoria has been shown using sequential reversed-phase high performance liquid chromatography separation coupled with radioimmunoassay and bioassay. The peptide is present in areas of the oviduct which receive extensive innervation, with sixfold less peptide in areas that receive little innervation. Material with FMRFamide-like immunoreactivity (determined by radioimmunoassay) is also present in the oviducal nerve and VIIth abdominal ganglion.SchistoFLRFamide is a potent modulator of contraction of this visceral muscle, inhibiting or reducing the amplitude and frequency of spontaneous contractions, relaxing basal tonus, and reducing the amplitude of neurally-evoked, proctolin-induced, glutamate-induced and high potassium-induced contractions. The FMRFamide-like immunoreactivity within the oviducts which co-elutes with SchistoFLRFamide on two separations is also capable of reducing the amplitude of neurally-evoked and proctolin-induced contractions, and of inhibiting spontaneous contractions and relaxing basal tonus.The effects of SchistoFLRFamide upon this visceral muscle are not abolished by the -adrenergic receptor antagonist phentolamine and do not appear to be mediated by cyclic AMP. Thus the receptors for Schisto-FLRFamide are distinct from those of octopamine which mediate similar physiological effects but which are blocked by phentolamine and which are coupled to adenylate cyclase.The results indicate that SchistoFLRFamide, or a very similar peptide, which has previously been identified as a modulator of locust heart beat, is also associated with visceral muscle of the reproductive system, and may play a neural role in concert with octopamine, at modulating muscular activity.Abbreviations BPP Bovine pancreatic polypeptide - BSA Bovine serum albumin - EJP Excitatory junctional potential - FaRPs FMRFamide-related peptides - FLI FMRFamide-like immuno-reactivity - LMS Leucomyosuppressin - RIA Radioimmunoassay - RP-HPLC Reversed-phase high performance liquid chromatography - TFA Trifluoroacetic acid     

Induction of lymphokine-activated killer activity in rat splenocyte cultures: The importance of 2-mercaptoethanol and indomethacin

Summary The role of 2-mercaptoethanol and indomethacin in the induction of lymphokine-activated killer (LAK) activity by interleukin-2 (IL-2) in rat splenocyte cultures was investigated. Spleens from 4-month-old male rats of five different strains were tested. Splenocytes were cultured for 3–5 days in the presence of IL-2 (1000 U/ml) and LAK activity was assessed by 4-h⁵¹Cr release assays with P815 and YAC-1 cells as targets. LAK activity could be induced by IL-2 in splenocytes from all rat strains, but only when 2-mercaptoethanol was present in the culture medium. Optimal LAK activity was induced when the 2-mercaptoethanol concentration in splenocyte cultures was at least 5 µM. Different rat strains showed differences in levels of in vitro induction of LAK activity. In the presence of 2-mercaptoethanol the level of LAK activity induced by IL-2 was high in BN and Lewis rats, intermediate in Wistar and Wag rats, and low in DZB rats. In the absence of 2-mercaptoethanol no or minimal LAK activity was induced. Furthermore we observed that addition of 50 µm indomethacin to the culture medium in the presence of 2-mercaptoethanol augmented the induction of LAK activity to some extent. In the absence of 2-mercaptoethanol, addition of indomethacin resulted only in low levels or no induction of LAK activity. We conclude that for optimal induction of LAK activity by IL-2 in rat splenocyte cultures 2-mercaptoethanol is essential, while indomethacin can only marginally further improve this induction.     

Observations on the seasonal and yearly occurrence and the distribution ofAtyaephyra desmaresti (Millet, 1831) (Crustacea,Decapoda, Natantia) in The Netherlands

Summary The seasonal occurrence ofAtyaephyra desmaresti in The Netherlands has been studied by sampling the cooling-water filtering screens of power stations situated along the rivers Rhine and Meuse. The shrimps were only found in large numbers at the two power stations with vegetation in the cooling-water intake areas. Fluctuations in the seasonal occurrence showed great similarity for these two localities. Highest numbers of shrimps were impinged in November. High numbers also occurred in September, while a lower peak in numbers was found in May.Changes in the numbers of records during the last 30 years in The Netherlands were compared with climatological fluctuations (severe or mild winters), indicating that this mainly southern-European species is living here at the limits of its ecological and geographical range.The distribution in The Netherlands reveals thatAtyaephyra desmaresti mainly occurs in freshwater habitats, although it tolerates higher chlorinities.     

Release of dopamine, noradrenaline and dopamine B-hydroxylase from mouse neuroblastoma

The murine C1300 neuroblastoma tumor was found to secrete dopamine, noradrenaline and dopamine B-hydroxylase into the circulation of tumor-bearing A/J mice. The plasma levels of dopamine, noradrenaline and dopamine B-hydroxylase increased with the size of the tumor, and the increase in noradrenaline paralleled the increase in dopamine B-hydroxylase (r = 0.86). The vesicular storage of dopamine and noradrenaline in the tumor was evidenced by a decrease of the tissue content of dopamine and noradrenaline 24 hours after the administration of reserpine (5 micrograms/g) respectively to 17.6% and 7.8% of control values. A similar observation could be made for the levels of dopamine and noradrenaline in the plasma of reserpinized C1300 mice. The total activity of dopamine B-hydroxylase in the tumor and in plasma was unaffected by the reserpine treatment. Chronic administration of 6-hydroxydopamine (100 micrograms/g for 8 days) had no effect on the tissue contents of dopamine, noradrenaline or dopamine B-hydroxylase. The release of catecholamines and dopamine B-hydroxylase from the C1300 neuroblastoma was studied in vitro on superfused tumor slices. Stimulation of these slices with 56 mM KC1 or with 5.10(-5) M tyramine failed to induce the release of endogenous dopamine, noradrenaline or dopamine B-hydroxylase above the basal outflow levels. These results are suggestive for a non-exocytotic release of catecholamines and dopamine B-hydroxylase from the neuroblastoma tumor.     

“Unblocking” Serum Activity <Emphasis Type="Italic">in vitro</Emphasis> in the Polyoma System may Correlate with Antitumour Effects of Antiserum <Emphasis Type="Italic">in vivo</Emphasis>

In a variety of tumour systems, individuals carrying progressively growing neoplasms have lymphoid cells with a specific cytotoxic effect on cultured tumour cells from the same individual^1–4. Since the sera of tumour-bearing individuals have been shown to prevent tumour cell destruction by immune lymphocytes in vitro^2,5–8 and since this serum blocking activity appears early in primary and transplant tumour development^5,7, it has been suggested that the appearance of this serum blocking activity might be responsible for the progressive growth of tumours in individuals having cytotoxic lymphocytes. Counteraction of this blocking activity would thus be of primary importance in facilitating the function of an already existing or bolstered cell-mediated immunity. The serum blocking activity might be inhibited in various ways, by preventing the formation of blocking antibody or by interfering with its action (“unblocking”), as demonstrated in Moloney sarcoma regressor sera⁹. This type of serum also has a therapeutic effect on Moloney sarcomas in vivo^10,11, which has been tentatively attributed to its unblocking activity^8,9 or, possibly, to a complement-dependent cytotoxicity¹⁰. Tumour growth in the Moloney sarcoma system, however, might be due in part to continuous recruitment of neoplastic cells by virus-induced transformation and so the therapeutic effect could be due to a virus-neutralizing serum activity^9,10.