Isolation and molecular characterization of a mouse renal microvascular endothelial cell line

Murine endothelial cells (ECs) have proven difficult to obtain and maintain in culture. Long-term maintenance of normal ECs remains a difficult task. In this article we report the establishment of the first cellular line of renal microvascular endothelium obtained from normal tissue. Cells were isolated, cloned, and maintained by serial passages for longer than 24 mo, using endothelial cell growth supplement (ECGS) and gelatin-coated plates. Their morphology and ultrastructure, expression of von Willebrand factor, presence of smooth muscle alpha-actin, vimentin, cytokeratin filaments, capillary structures formed on Matrigel, and some typical ECs surface molecules were the criteria used to characterize cultured ECs. When examined for responsiveness to Shiga toxin-1, 13-20% of cytotoxicity was observed when coincubated with lipopolysaccharides. This cytotoxicity was not observed for normal lung ECs (1G11). Consequently, REC-A4 line retains characteristics of resting microvascular ECs and represents a useful in vitro model to study biological and physiopathological properties of renal endothelium.     

Effect of some pharmaceutical excipients on the survival of probiotic vaginal lactobacilli

Lactobacilli are the predominant microorganisms of the vaginal bacterial microbiota, and they play a major role in the maintenance of a healthy urogenital tract. In consequence, the interest in their potential use as probiotics has significantly increased during the last decade. In the present study we assessed the influence of different excipients on the survival of 4 probiotic vaginal lactobacilli incorporated into glycerinated gelatin ovules and stored at 5 degrees C for 60 d. Results showed that viability after storage was a strain-dependent characteristic, but inclusion of ascorbic acid significantly increased survival in 3 of the 4 strains tested. The best survival was observed for Lactobacillus salivarius CRL 1328 in ovules containing skimmed milk. No significant differences in viability were observed between control ovules (glycerogelatin base without excipients) and those containing lactose or Tween 80 for any of the strains tested. Lactobacillus acidophilus CRL 1259 and Lactobacillus crispatus CRL 1266 were, respectively, the most resistant and sensitive strains to the storage with the different substances. In conclusion, these results provide a basis for selecting excipients to improve the survival of lactobacilli in a probiotic product, in an attempt to ensure the delivery of an adequate number of viable cells to the urogenital tract.     

A model-independent algorithm to derive Ca2+ fluxes underlying local cytosolic Ca2+ transients

Local intracellular Ca(2+) signals result from Ca(2+) flux into the cytosol through individual channels or clusters of channels. To gain a mechanistic understanding of these events we need to know the magnitude and spatial distribution of the underlying Ca(2+) flux. However, this is difficult to infer from fluorescence Ca(2+) images because the distribution of Ca(2+)-bound dye is affected by poorly characterized processes including diffusion of Ca(2+) ions, their binding to mobile and immobile buffers, and sequestration by Ca(2+) pumps. Several methods have previously been proposed to derive Ca(2+) flux from fluorescence images, but all require explicit knowledge or assumptions regarding these processes. We now present a novel algorithm that requires few assumptions and is largely model-independent. By testing the algorithm with both numerically generated image data and experimental images of sparklets resulting from Ca(2+) flux through individual voltage-gated channels, we show that it satisfactorily reconstructs the magnitude and time course of the underlying Ca(2+) currents.     

New Host and Locality Records for the Ixodes Auritulus (Acari: Ixodidae) Species Group, with a Review of Host Relationships and Distribution in the Neotropical Zoogeographic Region

New Neotropical records are presented for ticks belonging to the Ixodes auritulus Neumann, 1904, species group, together with a review of hosts and localities from which members of this complex have previously been collected. The range of the I. auritulus species group is now understood to include Colombia, and 15 bird species are listed as new hosts. From Guatemala to southern Argentina and Chile, specimens of the I. auritulus group have been found on birds belonging to the orders Ciconiiformes, Columbiformes, Falconiformes, Galliformes, Passeriformes, Piciformes, Procellariiformes and Tinamiformes. Passeriform birds are probably the principal hosts, sustaining tick populations throughout the Neotropics. Collection data have yielded four areas – southern South America (from 56° S to 51° S), southern Brazil (25° S–22° S), south-central Peru (14° S–10° S) and Central America (10° N–15° N) – where the I. auritulus group appears to commonly parasitize birds, but additional collections may show that the range of this complex is less discontinuous than currently perceived. Several morphological differences are described for ticks within and among these areas, but it is still unclear whether the I. auritulus group comprises more than one species.     

The crystal structure and physicochemical characteristics of 2-hydroxy-N-[3(5)-pyrazolyl]-1,4-naphthoquinone-4-imine,a new antitrypanosomal compound

This study was designed to investigate the physical characteristics and crystalline structure of 2-hydroxy-N-[3(5)-pyrazolyl]-1,4-naphthoquinone-4-imine (PNQ), a new active compound against Trypanosoma cruzi, the causative agent of American trypanosomiasis. Methods used included differential scanning calorimetry, thermogravimetry, hot stage microscopy, polarized light microscopy (PLM), Fourier-transform infrared (FTIR) spectroscopy, and high-resolution X-ray powder diffraction (HR-XRPD). According to PLM and HR-XRPD data, PNQ crystallized as red oolitic crystals (absolute methanol) or prisms (dimethyl sulfoxide [DMSO]-water) with the same internal structure. The findings obtained with HR-XRPD data (applying molecular location methods) showed a monoclinic unit cell [a = 18.4437(1) A, b = 3.9968(2) A, c = 14.5304(1) A, alpha = 90 degrees , beta = 102.71(6) degrees , gamma = 90 degrees , V = 1044.9(1) A(3), Z = 4, space group P2(1)/c], and a crystal structure (excluding H-positions) described by parallel layers in the direction of the b-axis, with molecules held by homochemical (phenyl-phenyl and pyrazole-pyrazole) van der Waals interactions. In addition, FTIR spectra displayed the NH-pyrazole stretch overlapped with the OH absorption at 3222 cm(-1), typical of -NH and -OH groups associated through H-bondings; and a carbonyl stretching absorption at 1694 cm(-1), indicating a nonextensively H-bonded quinonic C=O, which was in accordance with the solved crystal structure of PNQ. The existence of such cohesive forces shed light on the thermoanalytical data, which revealed that PNQ is a stable solid, unaffected by oxygen that decomposed without melting above 260 degrees C.     

Bog bursts

Variously attributed to earthquakes, lightening strikes, Acts of God, witchcraft, the wrath of the fairies, or the fertile Irish imagination, bog bursts are dramatic but poorly understood natural phenomena. This article attempts a scientific appraisal.     

Correlation of Increased Grooming Behavior and Motor Activity with Alterations in Nigrostriatal and Mesolimbic Catecholamines After α-Melanotropin and Neuropeptide Glutamine–Isoleucine Injection in the Rat Ventral Tegmental Area

1. We wished to further study the behavioral effects of -melanotropin (-MSH), melanin-concentrating hormone (MCH), and neuropeptide glutamine–isoleucine (NEI).2. To this effect we administered -MSH, MCH, and NEI in the ventral tegmental area of the rat, a structure where these neuropeptides are highly concentrated. To further elucidate the biochemical mechanisms of the behavioral effect of these neuropeptides, we determined the degree of grooming behavior and the levels of catecholamines, after neuropeptide administration.3. We preselected those animals responding to the central injection of -MSH with excessive grooming behavior. We administered the neuropeptides at the dose of 1 g/0.5 L, in each side of the ventral tegmental area, bilaterally. We studied grooming behavior, locomotor activity, and total behavior scores, 30 and 65 min after administration of the peptides.4. Three groups of animals were decapitated immediately after the injection of the neuropeptides, and 30 or 65 min after injection. We measured dopamine (DA), noradrenaline (NA), and the dopac/dopamine ratio (DOPAC/DA) to determine steady state levels of catecholamines and an indirect measure of DA release and metabolism, respectively.5. Injections of -MSH produced significant elevations in grooming behavior, locomotor activity, and total behavior scores, both 30 and 65 min after peptide administration. This was correlated with significant decreases in DA content, increases in DOPAC content, and increases in the DOPAC/DA ratio. In the caudate putamen, changes in catecholamines occurred both at 30 and 65 min after injection. In the nucleus accumbens, changes were present at 65 min after injection. Conversely, there were no alterations in NA content, either in the caudate putamen or in the nucleus accumbens, at any time after the injection.6. Injections of NEI resulted in significant elevations in grooming behavior, locomotor activity, and total behavior scores, both 30 and 65 min after peptide administration. This was correlated with increased DOPAC/DA ratio in the nucleus caudatus but not in the nucleus accumbens. Conversely, NEI produced increased NA concentrations in the nucleus accumbens, but not in the nucleus caudatus.7. Injections of MCH did not produce significant changes in behavior or significant changes in nucleus caudatus or nucleus accumbens catecholamines.8. Our results indicate (a) There is a correlation with alterations in behavior as induced for the neuropeptides injected here, and changes in extrapyramidal catecholamines. (b) There is a correlation between alterations in behavior and increases in DOPAC/DA ratio in the nucleus caudatus. (c) There is a correlation between alterations in behavior and alterations in catecholamines in the nucleus accumbens. In the nucleus accumbens, DOPAC/DA ratio is changed after -MSH, and NA ratio is changed after NEI injection. (d) Absence of alterations in extrapyramidal catecholamines, and in particular in catecholamines in the nucleus accumbens, correlates with absence of behavioral alterations after neuropeptide administration to the ventral tegmental area.9. In conclusion, the behavioral effect of exogenous administration of neuropeptides in the ventral tegmental area is peptide-specific, and is probably associated with alterations in catecholamine metabolism and release in the nucleus caudatus and the nucleus accumbens. Both -MSH and NEI seem to stimulate the nigrostriatal DA system. While -MSH appears to stimulate the mesolimbic DA system as well, NEI may exert its actions not through the DA, but through the NA mesolimbic system. The precise contribution of DA and NA, and the relative role of the nucleus caudatus and nucleus accumbens in these behaviors remain to be elucidated.     

Ancestral covariance and the Bulmer effect

Summary An n-generation pedigree is set up and selection is carried out generation by generation. The influence of this procedure on the covariances in subsequent generations is assessed and, ultimately, Bulmer's general recursion formula for the reduction in genetic variance due to selection is obtained. The results are extended to assess the effect of selection of one or more characters on the genetic covariance matrix of a number of characters. The concept of ancestral regression is also used to provide a different insight into the selection process and to justify some models used in the analysis of assortative mating.     

An Updated Review of the Avian Footprint Record from the Yacoraite Formation (Maastrichtian-Danian), Northwestern Argentina

Abstract

The Yacoraite Formation (Maastrichtian–Danian; Balbuena Subgroup; Salta Group), from Northwestern Argentina, represents a shallow epeiric unit which is the result of transgressions in the Andean basin of South America. Herein, we study the avian footprints from the Maimará locality, Jujuy province, and Quebrada del Tapón ichnosite, Salta province. The avian footprints from the Maimará locality is less diverse, made up: cf. Alaripeda isp., Avipeda isp., cf. Gruipeda filiportatis, and cf. Gruipeda isp. The avian track record from the Quebrada del Tapón ichnosite is composed of: cf. Alaripeda isp., Ardeipeda cf. egretta., Gruipeda filiportatis (=Yacoraitichnus avis) and others Gruipeda or compared to this ichnogenus, cf. Uhangrichnus isp., and several indetermined avian footprints. Both ichnological assemblages have tracks assigned to shorebirds or Charadriiformes. The facies distribution of trace fossils reinforces the overall model of a shorebird tracks dominance in moderate to low energy settings. This distribution can be divided into three sub-environments: (1) a moderate to high energy shoreline under wave action, (2) a supratidal body of ephemeral ponds, far away from direct wave influence and (3) a landward position, beyond the ephemeral ponds system. We have included all the ichnoassemblages within the shorebird ichnosubfacies as a subset of the Scoyenia Ichnofacies.