On two nematodes from Brazilian birds and description of a new species (Acuarioidea, Schistorophinae) parasitizing Laterallus viridis (Müller, 1776) (Gruiformes, Rallidae)

The present paper reports acuarioid nematodes recovered from avian hosts. A new species of the genus Schistorophus Railliet, 1916 is proposed based mainly on findings referring to ptilina, spicules and vagina. Ancyracanthopsis coronata (Molin, 1860) Chabaud & Petter, 1959 is referred again in Brazil since its proposition in 1860, from specimens recovered from a Brazilian bird. A revised key to the species of the genus Schistorophus is also presented.     

Pyrite Suspended in Artificial Sea Water Catalyzes Hydrolysis of Adsorbed ATP: Enhancing Effect of Acetate

Minerals have been implicated in different catalytic processes during chemical evolution. It has been proposed that exergonic synthesis of pyrite (FeS₂) could have served to promote the endergonic synthesis of biomonomers in early stages of life formation on Earth. The present study was aimed to investigate whether pyrite can adsorb nucleotides and oxo acids in the potentially mild prebiotic conditions found away from the hot hydrothermal vents. It is shown that pyrite strongly adsorbs adenosine 5-triphosphate in an artificial medium that simulates primordial aqueous environments, and that adsorption is enhanced in the presence of acetate and in an oxygen-free atmosphere. Moreover, the mineral catalyzes the sequential hydrolysis of the and phosphoanhydride bonds of the nucleotide.     

An Mn2+-stimulated neutral-sphingomyelinase in seminiferous tubules of immature Wistar rats

Mammalian sphingomyelinases have been implicated in many important physiological and pathophysiological processes. The seminiferous tubules of immature (19 day-old) Wistar rats have at least three types of sphingomyelinases, a lysosomal one and two microsomal ones. One of the microsomal sphingomyelinases is active at pH 6.5 and is stimulated by Mn²⁺ > Co²⁺ > Mg²⁺, and the other is active at pH 7.4 and is stimulated by Mn²⁺ > Mg²⁺ and inhibited by Co²⁺. The two microsomal enzymes are only slightly inhibited by EDTA and at pH 7.4 the stimulatory effects of Mn²⁺ and Mg²⁺ are additive. These data characterize the existence of two different membrane-bound sphingomyelinases in the seminiferous tubules of the rat.     

Separate taurine and chloride efflux pathways activated during regulatory volume decrease

Organic osmolyte and halide permeability pathways activated inepithelial HeLa cells by cell swelling were studied by radiotracer efflux techniques and single-cell volume measurements. The replacement of extracellular Cl byanions that are more permeant through the volume-activated Cl channel, as indicated byelectrophysiological measurements, significantly decreasedtaurine efflux. In the presence of less-permeant anions, an increase intaurine efflux was observed. Simultaneous measurement of the¹²⁵I, used as a tracer forCl, and[³H]taurine effluxshowed that the time courses for the two effluxes differed. InCl-rich medium the increasein I efflux was transient,whereas that for taurine was sustained. OsmosensitiveCl conductance, assessed bymeasuring changes in cell volume, increased rapidly after hypotonicshock. The influx of taurine was able to counteractCl conductance-dependentcell shrinkage but only ~4 min after triggering cell swelling. Thistaurine-induced effect was blocked by DIDS. Differences in anionsensitivity, the time course of activation, and sensitivity to DIDSsuggest that the main cell swelling-activated permeability pathways fortaurine and Cl are separate.

     

DNA extraction and PCR amplification method suitable for fresh, herbarium-stored, lichenized, and other fungi

This paper presents a DNA extraction method suitable for fresh, herbarium-stored, lichenized and other fungal specimens. The method is fast and reliable, comparatively inexpensive and is suitable for obtaining PCR amplification quality DNA from large numbers of samples in a short time. The method has been tested with over 300 samples ofAscochyta, Phyllosticta, Ramalina, Parmelia andPhysconia. Amplifiable fungal DNA was extracted from pure cultures, leaf lesions, whole thalli and dissected only-fungal sections of lichenized fungi. In addition, the method has proved suitable for use with herbarium specimens of both lichenized and non-lichenized fungi, stored as dried pure cultures or dried infected plant material.     

Revised structures for the bejarols from Santolina oblongifolia

The ¹³C NMR spectra of the bejarols isolated from Santolina oblongifolia suggest they are nerolidol derivatives with a 2,6-dialkyldihydropyranose structure.     

Differential and common leukemogenic potentials of multiple NUP98-Hox fusion proteins alone or with Meis1

NUP98-Hox fusion genes are newly identified oncogenes isolated in myeloid leukemias. Intriguingly, only Abd-B Hox genes have been reported as fusion partners, indicating that they may have unique overlapping leukemogenic properties. To address this hypothesis, we engineered novel NUP98 fusions with Hox genes not previously identified as fusion partners: the Abd-B-like gene HOXA10 and two Antennepedia-like genes, HOXB3 and HOXB4. Notably, NUP98-HOXA10 and NUP98-HOXB3 but not NUP98-HOXB4 induced leukemia in a murine transplant model, which is consistent with the reported leukemogenic potential ability of HOXA10 and HOXB3 but not HOXB4. Thus, the ability of Hox genes to induce leukemia as NUP98 fusion partners, although apparently redundant for Abd-B-like activity, is not restricted to this group, but rather is determined by the intrinsic leukemogenic potential of the Hox partner. We also show that the potent leukemogenic activity of Abd-B-like Hox genes is correlated with their strong ability to block hematopoietic differentiation. Conversely, coexpression of the Hox cofactor Meis1 alleviated the requirement of a strong intrinsic Hox-transforming potential to induce leukemia. Our results support a model in which many if not all Hox genes can be leukemogenic and point to striking functional overlap not previously appreciated, presumably reflecting common regulated pathways.