CFU-gm assay, cytochemical and electron microscopic studies in agar in patients with preleukemic syndrome and aplastic anemia

Thirty-seven patients with chronic cytopenia were studied using a CFU-gm assay in agar. Cell proliferation was evaluated on days 2, 3, 5, 7, and 10 of incubation. Growth patterns were different in cultures of hematologically healthy persons versus patients with preleukemic syndrome (PL) and aplastic anemia (AA). Three types of PL syndrome and two types of AA (C1 and C2) were distinguished. Bone marrow dysfunction was evaluated further using cytochemistry and electron microscopy to morphologically study cell proliferation in vitro. Cytochemical staining performed in agar demonstrated well-defined maturation defects in myelopoietic precursor cells from the bone marrow of PL patients. Electron microscopic findings of Auer-body-like inclusions in "statu nascendi" in the vacuoles of preleukemic cells supported our results. PL patient groups at high risk for development of overt leukemia and patients with grave prognosis in AA were distinguished. Our results are relevant for the clinical diagnosis and prognosis of patients with cytopenia.     

The distribution of fatty acids including petroselinic and tariric acids in the fruit and seed oils of the Pittosporaceae, Araliaceae, Umbelliferae, Simarubaceae and Rutaceae

The fatty acid composition of the fruit oils or seed oils of Pittosporaceae (eight genera, 10 species), Araliaceae (two species), Simarubaceae (three species), and of one umbelliferous and one rutaceous species were determined by gas chromatography, argentation TLC and ozonolysis. In the Pittosporaceae, in which the major C₁₈ fatty acid of all species was either oleic acid (18:1, 9c) or linoleic acid (18:2, 9c, 12c), large amounts of C₂₀ and C₂₂ fatty acids seem to occur regularly. Petroselinic (18:1, 6c) and tariric (18:1, 6a) acids were absent. However, petroselinic acid was the major fatty acid in the Araliaceae and Umbelliferae. In these two families only small amounts of C₂₀ and C₂₂ acids were detected and tariric acid was absent. The Rutales contained relatively high amounts of trans-octadecenoic acids (18:1, 9t). Tariric acid was the major fatty acid in the two species of Picramnia (Simarubraceae), which also contained small amounts of petroselinic acid. The major fatty acids in Ailanthus glandulosa (Simarubaceae) and Phellodendron amurense (Rutaceae) were linoleic or linolenic acid (18:3, 9c, 12c, 15c); these species contained neither tariric nor petroselinic acid and the levels of C₂₀ and C₂₂ fatty acids were low. The appearance of schizogenous resin canals and polyacetylenes and the absence of iridoids and petroselinic acid allows the Pittosporaceae to be separated from the Rutales and Araliales and to be placed in an independent order, the Pittosporales. Arguments for a rather close relationship of the Pittosporales to the Araliales and Cornales (including the Escalloniaceae) are presented.     

Animal community structure as a function of stream size

The species-area relationship of the island biogeography theory was calculated for macroinvertebrates in 22 coastal, adjacent streams. A z-value of 0.19 was obtained. The low z-value was probably a consequence of the short distances between streams as well as high dispersal rates. In addition, a cluster analysis based on the dissimilarity of species assemblages showed that stream size was of prime importance in categorizing the streams. To a smaller extent water quality affected the community structure in the streams.     

An examination of the factors involved in determining phosphatase activities in estuarine water. 1: Analytical procedures

The effects of assay pH, magnesium addition, temperature, sodium azide, and of sample storage and filtration on the apparent phosphatase activities in natural water bodies, and in particular estuaries, have been examined. Phosphatase activity was assessed by monitoring the cleavage of p-nitrophenol from p-nitrophenyl phosphate (pNPP). Magnesium concentrations in natural waters were found to be generally in excess of the requirement of the assay procedure. Several pH maxima occurred for phosphatase activities in the estuarine waters examined. These optima were not constant with respect to sampling stations or sampling time. This was considered to be, in part, the result of differences in the biomass composition. Sample storage times and temperatures employed in the present study did not influence the phosphatase activities of these low biomass waters. Phosphatase activities increased with increased incubation temperature. The rate of orthophosphate release from pNPP during incubation was linear over time to 120 h. Sodium azide was found to be an adequate preservative when long incubation times were required. The effects of assay conditions are discussed in relation to the assay procedures and data interpretation.     

Anti-predator adaptations in a neustonic insect (Velia caprai)

Summary The risk of a Velia caprai (Heteroptera: Veliidae) individual to fall victim to brown trout (Salmo trutta) was demonstrated experimentally to be markedly lower when several bugs were simultaneously exposed to the trout. V. caprai was found distasteful to brown trout, and a high proportion was ejected alive after being captured. We suggest that school formation in V. caprai lowers the risk of predation because frequent predator-prey encounters may assist in retention of the avoidance learned by the predator. Individual behavioural responses to attacks were variable and the frequency of expansion skating and thanatosis was temperature dependent. Thanatosis postures were either symmetric with the legs pressed to the body or irregular.     

The meaning and measurement of size hierarchies in plant populations

Summary The term size hierarchy has been used frequently by plant population biologists but it has not been defined. Positive skewness of the size distribution, which has been used to evaluate size hierarchies, is inappropriate. We suggest that size hierarchy is equivalent to size inequality. Methods developed by economists to evaluate inequalities in wealth and income, the Lorenz curve and Gini Coefficient, provide a useful quantification of inequality and allow us to compare populations. A measure of inequality such as the Gini Coefficient will usually be more appropriate than a measure of skewness for addressing questions concerning plant population structure.     

Immunocytochemical localization of microtubule-associated protein 1 in rat cerebellum using monoclonal antibodies

Immunohistochemical staining with monoclonal antibodies showed that microtubule-associated protein 1 (MAP1) has a restricted cellular distribution in the rat cerebellum. Anti-MAP1 staining was found only in neurons, where it was much stronger in dendrites than in axons. There were striking variations in the apparent concentration of MAP1 in different classes of neurons. Purkinje cells were the most strongly labeled, while granule cell neurons gave a faint, threshold-level reaction with the antibody. The reaction of Golgi neurons was intermediate between these two extremes. Equivalent results were obtained using two different methods of tissue preparation. Thus MAP1 appears to be a neuron-specific protein that is highly concentrated in dendrites and occurs at markedly different levels in different types of neurons. These observations provide further indications of heterogeneity among brain microtubules.     

Selective activation by thymus-dependent antigens of distinct B cell subpopulations expressing a major cross-reactive idiotype

We determined the B cell subpopulations that produce the major cross-reactive idiotype (CRIA) associated with the anti-phenylarsonate (ARS) antibody response of A/J mice. Specifically, we examined the B2 subpopulation found in normal mice which, in H-2b mice, bears the I-Ab-encoded determinant Ia.W39; the B1 subpopulation found in mice expressing the CBA/N X-linked immunodeficiency trait (xid); and the B1 subpopulation found in normal mice after the cytotoxic elimination of B2 cells with anti-Ia. W39 and complement. CRIA is expressed in each of these B cell subpopulations. Antigen plays a selective role in the stimulation of distinct B cell sets. ARS conjugates of keyhole limpet hemocyanin (KLH) can activate both the B1 and B2 subpopulations. In contrast, ARS conjugates of synthetic polypeptides under Ir gene control selectively activate the B2 subpopulation in strains that are genetic responders to the carrier. This leads to the establishment of CRIA dominance where CRIA+ anti-ARS antibody is 70 to 95% of the total anti-arsonate antibody response. This class of antigens fails to activate the B1 cells in either normal or xid mice. We compared the CRIA+ antibody produced by selectively activated B2 cells to that produced by the B1 subpopulation in xid mice. For these comparisons, we used competitive radioimmunoassays that employed polyspecific anti-CRIA antiserum or monoclonal anti-CRIA antibodies specific for distinct idiotopes on the heavy chain of CRIA+ antibody. B2 cells produce a CRIA+ anti-ARS antibody that is idiotopically uniform among individual mice, and that closely approximates the hybridoma protein 36-65 (the heavy chain of 36-65 represents the germ line-encoded sequence of the unique CRIA structural gene (25]. In contrast, the CRIA+ antibody produced by the B1 cell subset of xid mice is idiotopically diverse among individual mice, and differs markedly from the 36-65 hybridoma protein. The extent of diversification found in CRIA+ antibody depends on the B cell subpopulation that produces it.     

Infectious diarrhea of infant rats produced by a rotavirus-like agent.

During the investigation of an outbreak of diarrhea in suckling rats, a virus morphologically identical to but antigenically distinct from rotaviruses was identified. The disease was characterized clinically by erythema and cracking and bleeding of the perianal skin associated with the excretion of poorly formed fecal pellets, liquid, and gas. Light microscopy-observable changes consisted of small intestinal villous atrophy, villous epithelial necrosis, and villous epithelial syncytial cell formation. The cytoplasm of the epithelial syncytial cells contained large numbers of 80-nm viral particles that were often associated with reticular aggregates of electron-dense material. Viral infection principally involved the luminal one-fourth to one-third of the intestinal villi as determined by indirect immunofluorescence. This rotavirus-like agent contained 11 double-stranded RNA segments; however, the migration pattern of these segments in polyacrylamide gels differed from the electrophoretic pattern which is characteristic of the typical rotaviruses. The agent had a buoyant density in CsCl of 1.36 to 1.4 g/cm3 and was labile at pH 3 and at 56 degrees C; however, infectivity of viral inocula was not altered by extensive treatment with ether or by pH 5 buffers. This disease, which we have named infectious diarrhea of infant rats, is the first recognized viral diarrhea of rats and appears to be a good model for the study of the recently recognized group of atypical rotaviruses.     

Prostaglandin 12 reduces activation of human arterial smooth muscle cells in-vivo

Patients suffering from peripheral vascular disease have been “ultima ratio”-treated with PGI2 at a rate of 5 ng/kg/min for 6 hours a day and 5 consecutive days i.v. 20 of them underwent surgery thereafter as therapy was not sufficient. A histological examination and quantification of vascular tissue revealed that the number of activated smooth muscle cells was significantly lower in treated patients vascular segments than in untreated ones in all the different age groups. A comparable suppression was found in the intima and the media as well. It is thus concluded, that PGI2 inhibits smooth muscle cell proliferation most probably by inhibiting PDGF-release from the platelets and stimulation of smooth muscle cell cAMP. To achieve a more beneficial PGI2-effect at the vascular level, a prolonged PGI2-therapy looks rather promising.