Miracle-dz/UniFAR-FTUs huggingface dataset:
Phenoloxidase activity in the haemolymph and haemocytes of the marine mussel Mytilus edulis

Cytocentrifuge preparations of mussel haemocytes were tested cytochemically, using both light and electron-microscopy, for the presence of phenoloxidase activity which was demonstrated by incubation with the substrate dihydroxyphenylalanine. The blood-cells were also tested for peroxidase activity using the substrate diaminobenzidine. Both enzyme techniques produced a reaction product in the cytoplasmic granules of the eosinophilic cells which varied in its intensity within and between haemolymph samples. The activity was demonstrated to be the result of two distinct enzymes within the same cell type using the following criteria: differential inhibition; contrasting percentages of phenoloxidase and peroxidase-positive cells within pooled samples; variation in numbers of positive cells over time in a seasonal survey; differential localisation of the reaction products in different size granules as seen ultrastructurally. Activation of the phenoloxidase enzyme was demonstrated biochemically using a 96-well microplate reader; preincubation of the cells with 0·025% zymosan-supernatant produced a ten-fold increase in activity as compared with those preincubated in phosphate buffered saline or 0·1% zymosan. The results are discussed in relation to the possible significance of the presence of phenoloxidase in the defence cells of Mytilus edulis and the role of its activation in vivo.
Optimal conditions for the culture of Amphiascoides atopus (Harpacticoida: Miraciidae) from Mazatlan, Sinaloa State, Mexico

Abstract The effects of the most important factors (food quality and quantity, temperature, and salinity) on the production of the harpacticoid copepod Amphiascoides atopus Lotufo & Fleeger, originally described from a mass culture system at the Department of Zoology and Physiology of the Louisiana State University at Baton Rouge, were evaluated to ascertain potential yields. For aquacultural purposes, it is important to assess these factors for laboratory-controlled conditions. Feeding treatments were not significantly different between monospecific (Chaetoceros muelleri, Isochrysis sp., and Nannochloropsis oculata) and mixed diets (all three of the mentioned diets in ratios of 1:1:1) (527.2 ± 68.3 to 404.4 ± 160.6 organisms L−1). Copepods fed diets of 320 cells μL−1 (539.6 ± 115.8 organisms L−1) showed the highest mean egg production. Our results demonstrate that a temperature of less than 20°C (15 ± 3.5 organisms L−1) significantly affected the final mean population counts. No statistical differences were observed at 24, 28, and 32°C with productions varying between 330 ± 67.4 to 527 ± 101.3 organisms L−1. Of all the salinity levels tested, the highest population densities were recorded at 32 psu (983.0 ± 78.8 organisms L−1). Identifying the correct copepod species as live prey for larviculture is also considered important so that the appropriate size and characteristics of the food can be administered. These findings suggest that the copepod A. atopus can serve as a good potential live feed for larviculture.
The Dominant Negative Activity of the Human Glucocorticoid Receptor β Isoform

Alternative splicing of the human glucocorticoid receptor gene generates a nonhormone binding splice variant (hGRβ) that differs from the wild-type receptor (hGRα) only at the carboxyl terminus. Previously we have shown that hGRβ inhibits the transcriptional activity of hGRα, which is consistent with reports of elevated hGRβ expression in patients with generalized and tissue-specific glucocorticoid resistance. The potential role of hGRβ in the regulation of target cell sensitivity to glucocorticoids prompted us to further evaluate its dominant negative activity in other model systems and to investigate its mode of action. We demonstrate in multiple cell types that hGRβ inhibits hGRα-mediated activation of the mouse mammary tumor virus promoter. In contrast, the ability of the progesterone and androgen receptors to activate this promoter is only weakly affected by hGRβ. hGRβ also inhibits hGRα-mediated repression of an NF-κB-responsive promoter but does not interfere with homologous down-regulation of hGRα. We show that hGRβ can associate with the heat shock protein hsp90 although with lower affinity than hGRα. In addition, hGRβ binds GRE-containing DNA with a greater capacity than hGRα in the absence of glucocorticoids. Glucocorticoid treatment enhances hGRα, but not hGRβ, binding to DNA. Moreover, we demonstrate that hGRα and hGRβ can physically associate with each other in a heterodimer. Finally, we show that the dominant negative activity of hGRβ resides within its unique carboxyl-terminal 15 amino acids. Taken together, our results suggest that formation of transcriptionally impaired hGRα-hGRβ heterodimers is an important component of the mechanism responsible for the dominant negative activity of hGRβ.
Precursors of U4 small nuclear RNA

The processing and ribonucleoprotein assembly of U4 small nuclear RNA has been investigated in HeLa cells. After a 45-min pulse label with [3H]uridine, a set of apparently cytoplasmic RNAs was observed migrating just behind the gel electrophoretic position of mature U4 RNA. These molecules were estimated to be one to at least seven nucleotides longer than mature U4 RNA. They reacted with Sm autoimmune patient sera and a monoclonal Sm antibody, indicating their association with proteins characteristic of small nuclear ribonucleoprotein complexes. The same set of RNAs was identified by hybrid selection of pulse-labeled RNA with cloned U4 DNA, confirming that these are U4 RNA sequences. No larger nuclear precursors of these RNAs were detected. Pulse-chase experiments revealed a progressive decrease in the radioactivity of the U4 precursor RNAs coincident with an accumulation of labeled mature U4 RNA, confirming a precursor-product relationship.
Biosynthesis of the modified peptide antibiotic thiostrepton in Streptomyces azureus and Streptomyces laurentii

The biosynthesis of the thiopeptide antibiotic thiostrepton (1) has been investigated by administration of isotopically labeled precursors to cultures of Streptomyces azureus and Streptomyces laurentii. The amino acid origin of all the components of the antibiotic was demonstrated. Experiments with (S)-[1,2- 13 C 2 ]- and (S)-[2,3- 13 C 2 ]serine showed intact incorporation of serine into the thiazoline and thiazole rings as well as the dehydroalanine, alanine, and tetrahydropyridine moieties. (S)-[3- 13 C, 2 H 2 ]Serine and (2S,3S)-[3- 13 C, 2 H 1 ]serine were used to elucidate the stereochemistry of the various transformations of serine
Planting Date Influence on Dual‐Purpose Winter Wheat Forage Yield, Grain Yield, and Test Weight

The use of winter wheat (Triticum aestivum L.) as a dual-purpose forage and grain crop is important to the agricultural economies of the Southern Great Plains of the USA. Planting date is an important management factor in determining the economic success of a dual-purpose winter wheat enterprise. The overall objective of the research reported in this paper is to determine the economic optimal planting date for dual-purpose winter wheat production. The specific objectives are to determine wheat fall-winter forage yield, wheat grain yield, and wheat test weight response to planting date for dual-purpose winter wheat production. Field studies were conducted in north central Oklahoma from 1991-1992 through 1999-2000. The impact of alternative planting dates on dual-purpose wheat fall-winter forage yield, grain yield, and test weight was estimated. Estimated response functions illustrate that delaying the planting date from 10 to 30 September resulted in an 18% increase in expected grain yield, a 68% decrease in expected fall-winter forage yield, and only a 0.5% increase in expected test weight. Optimal planting date is sensitive to the relative value of wheat fall-winter forage and wheat grain, but not sensitive to wheat test weight discount schedules. When the value of wheat forage is high relative to the value of grain, it is more profitable to plant early to increase expected forage yield. Alternatively, when the value of grain is high relative to the value of forage, later planting generates greater net returns.
Insect colour preference compared to flower colours in the Australian Alps

An apparent predominance of plant taxa with pale flowers in the alpine floras of Australia and New Zealand may be due to the prevalence of insects, such as flies, that prefer pale colours and the absence of other types of potential pollinators that are attracted to bright colours such as social bees and birds. In this study, the diversity of flower colours, and the preference of insects for different colours were examined for the largest contiguous alpine area in Australia, around Mt Kosciuszko. Out of an alpine flora of 204 taxa, 127 species were found to have large showy flowers. The most common flower colour among these taxa was white (53.5%), then yellow (21.3%), followed by pink (6.3%), and cream (6.3%). Only a handful of taxa had red, blue, brown, green, orange or purple flowers. When the colour preference of insects was tested using five different coloured traps (white, yellow, orange, red and purple), the most successful traps were white then yellow, with these two colours accounting for 66% of all individual insects collected. Diptera were the most common insects caught (576 insects greater than 4 mm in length, 31 morphotaxa) showing an apparent preference for white and yellow coloured traps over others. Therefore, the results add some support to the proposition that the ‘white’ flora of the Australian Alps may be associated with the colour preference of flies, which have previously been found to be the most common type of pollinators in the Kosciuszko alpine zone.
Factors affecting appressorium development in the vesicular–arbuscular mycorrhizal fungus Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe

SUMMARY Investigations on the luck of appressorium formation in the roots of the non-host plant Lupinus albus L. showed that root exudates do not inhibit mycelial growth of the vesicular-arbuscular mycorrhizal (VAM) fungus Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe, but that they hinder hyphal attachment and fungal recognition of roots. Exudates do not stimulate hyphal proliferation in the rhizosphere. G. mosseae hyphae were able to recognize and attach to excised root of both lupin and host plants, forming swellings resembling apressoria. No growth of G. mosseae hyphae was observed around simulated roots consisting of nylon, silk, polyamide and glass threads, whereas appressoria were formed on heterologous hyphae of VAM fungal species. The hypothesis that a purely thigmotropic stimulate could trigger hyphal attachment and the further differentiation of appressoria was excluded.
The Rieske Fe/S Protein of the Cytochromeb 6 /f Complex in Chloroplasts

The Rieske Fe/S protein, a nuclear-encoded subunit of the cytochromeb 6 /f complex in chloroplasts, is retarded in the stromal space after import into the chloroplast and only slowly translocated further into the thylakoid membrane system. As shown by the sensitivity to nigericin and to specific competitor proteins, thylakoid transport takes place by the ΔpH-dependent TAT pathway. The Rieske protein is an untypical TAT substrate, however. It is only the second integral membrane protein shown to utilize this pathway, and it is the first authentic substrate without a cleavable signal peptide. Transport is instead mediated by the NH2-terminal membrane anchor, which lacks, however, the twin-arginine motif indicative of ΔpH/TAT-dependent transport signals. Furthermore, transport is affected by sodium azide as well as by competitor proteins for the Sec pathway in chloroplasts, demonstrating for the first time some cross-talk of the two pathways. This might take place in the stroma where the Rieske protein accumulates after import in several complexes of high molecular mass, among which the cpn60 complex is the most prominent. These untypical features suggest that the Rieske protein represents an intermediate or early state in the evolution of the thylakoidal protein transport pathways.
Genetic analysis of some flowering time and adaptive traits in wheat

SUMMARY The present understanding of the genetic control of flowering in wheat is reviewed. Although this information will continue to be of value in breeding and in recognizing the role such genes have had in adapting the wheat crop to global agriculture, its use in defining the processes responsible for flowering will be limited. Progress here will depend on developments in model plant systems such as Arabidopsis, where methods for isolating genes are much more advanced than in wheat. These developments, which have already started, will probably be used to establish homologies between the genes for flowering within the cereals, as well as more widely. An understanding of the flowering process in wheat is likely to emerge from this approach. In the meantime, there are some unknowns in the genetics of flowering in wheat which need to be resolved. These include the identification of a gene(s) on the group 4 chromosomes of wheat which is homoeoallelic with the gene Sh in barley. Also, the proposed gene(s) delaying flowering and located on the group 6 chromosomes needs to be recognized and mapped. Similar needs occur for the group 1 chromosomes as well as the resolution of whether or not Vrn5 is correctly positioned on chromosome 7BS.
Effect of Hypoxia on Lipid Accumulation in Cultured Fibroblasts from Normal Rabbit and Watanabe Heritable Hyperlipidemic Rabbit

We studied the effect of hypoxia on lipid accumulation in cultured fibroblasts from normal rabbits (normal fibroblasts) and in low density lipoprotein (LDL) receptor-negative fibroblasts from WHHL (Watanabe heritable hyperlipidemic) rabbits (WHHL fibroblasts). These cells were incubated in medium with normolipemic rabbit serum (NRS) or hyperlipemic rabbit serum (HRS). The cells were incubated in a humidified atmosphere of either 20% O2, 75% N2, and 5% CO2 (control cells) or 2% O2, 93% N2, and 5% CO2 (hypoxic cells). After 48h incubation of normal fibroblasts in medium with 20% NRS, free fatty acid (FFA) levels were increased slightly and the triglyceride (TG) level markedly in hypoxic cells. In the medium with 20% HRS, in addition to the increased FFA and TG levels, the free cholesterol level was increased slightly and the esterified cholesterol level markedly in hypoxic cells. Moreover, in WHHL fibroblasts, which lack LDL receptors, cellular lipid accumulation was also observed after 48h incubation in the medium with 20% HRS, and hypoxic incubation enhanced the cellular cholesterol and TG accumulation, as in normal fibroblasts.These results suggest that under hyperlipemic conditions, non LDL receptor-mediated uptake of lipoproteins plays a major role in cellular lipid deposition and that tissue hypoxia promotes lipid accumulation in peripheral cells by the LDL receptor-independent mechanisms.
Endothelin-induced Endocytosis of Cell Surface ET Receptors

We demonstrate unusual features of the intracellular processing of endothelin-1 (ET-1) and its receptor ETA, the receptor subtype that mediates contraction of vascular smooth muscle cells. First, we show that in stably transfected CHO cells expressing ETA, binding of an ET-1 ligand induces rapid endocytosis of cell surface ETA. Receptor endocytosis was measured both by immunofluorescence and by radioiodinated antibodies specific for ETA. Second, we demonstrate that ET-1 remains intact for up to 2 h after endocytosis and, as judged by co-immunoprecipitation, internalized I-ET-1 remains bound to ETA receptors. We hypothesize that internalized ET-1, bound to ETA receptors, continues to activate a signal-transducing G protein, thus accounting for the prolonged period of contraction induced in smooth muscle cells by a single administration of ET-1.
Plants intertwine fluvial landform dynamics with ecological succession and natural selection : a niche construction perspective for riparian systems.

Aim To contribute to the development of a macroevolutionary framework for riparian systems, reinforcing conceptual linkages between earth surface processes and biological and ecological processes. Location Riparian systems. Methods Literature review leading to an original proposition for perceiving the functioning of riparian systems in a new and different way. Results Riparian systems provide diverse landforms, habitats and resources for animals and plants. Certain organisms, defined as ‘ecosystem engineers’, significantly create and modify the physical components of riparian systems. Many studies have highlighted such engineering effects by animals on riparian systems, but the identification and understanding of the effects and responses of plants within fluvial corridors have emerged only recently. The modulation of matter, resources and energy flows by engineering plants helps establish characteristic sequences of fluvial landform creation and maintenance associated with synergetic ecological successions. We relate this process to the concept of niche construction, developed mainly by evolutionary biologists. Feedbacks between adaptive responses of riparian plants to flow regime and adjusting effects on biostabilization and bioconstruction are discussed in the context of niche construction at the scale of ecological succession and the evolution of organisms. Main conclusions Our conceptualization forges an integrated approach for understanding vegetated fluvial systems from a macroevolutionary perspective, for elucidating riparian ecosystem dynamics and potentially for establishing long-term stream conservation and restoration strategies.
Molecular Modeling of Meta II Rhodopsin

A model believed to be representative for activated class A G protein-coupled receptors is proposed. It consists of rhodopsin and the transducin a C-terminal peptide [Gta(338 -350)] docked to it. The model utilizes the resolved interactions/distances, found to be essential in the activated rhodopsin (RD*) and the structure of Gta(338-350) that is known to stabilize RD*. Long-term molecular dynamics (14.8 ns) in fully hydrated lipid bilayer model is applied to the system to refine and verify conformational changes in rhodopsin itself and the structure of the complex. A concomitant role of Gta and Gtγ C-termini in stabilizing RD* could possibly be resolved assuming a receptor dimer as a requisite for G protein activation.
Use of Otolith Microchemistry to Discriminate Oncorhynchus nerka of Resident and Anadromous Origin

We used a wavelength dispersive microprobe to describe patterns in otolith microchemistry of sockeye salmon (Oncorhyncbus nerka). Patterns in Sr/Ca ratios in transects across otoliths were consistent with changes in environmental chemistry associated with life history. The patterns we observed were consistent with those described for other salmonids. We found that Sr/Ca ratios in otolith primordia of fish of known anadromous origin were significantly higher than those in otolith primordia of fish of known resident origin. However, variation among samples was associated with differences in chemistry of the freshwater environments. These differences could confound attempts to discriminate sympatric resident and anadromous forms in lakes where Sr/Ca ratios are high. Samples used to discriminate origin of emigrants from Redfish Lake, Idaho, confirmed the presence of both resident and anadromous fish, but the two groups were not clearly resolved. Otolith microchemistry has the potential to determine the parent.
CD45 Protein-tyrosine Phosphatase Is Specifically Associated with a 116-kDa Tyrosine-phosphorylated Glycoprotein (*)

CD45 is a protein-tyrosine phosphatase expressed on all cells of hematopoietic origin. In an attempt to further characterize CD45 function, we set out to identify molecule(s) that specifically associate with CD45. A 116-kDa protein was detected in immunoprecipitates from CD45 cells but not CD45 cells. The association between CD45 and this 116-kDa protein can be reconstituted by mixing lysates from CD45 cell lines with purified CD45. p116 appears to associate with CD45 through the external, transmembrane, or membrane-proximal region of CD45 since p116 is associated with a mutant form of CD45 possessing a truncated cytoplasmic domain. The association of p116 with CD45 is not isoform-specific as p116 associates equally well with various CD45 isoforms. We have determined that p116 is a tyrosine-phosphorylated glycoprotein and that it is associated with CD45 in all hematopoietic cells examined. Because of its broad distribution, it is possible that identification of p116 will provide additional insight into the function of CD45 in lymphoid as well as non-lymphoid hematopoietic cells.
Macneill's Sootywing (Hesperopsis gracielae) (Lepidoptera: Hesperiidae) Behaviors Observed Along Transects

Abstract Three transects were monitored to determine frequencies of behaviors of Hesperopsis gracielae (MacNeill) (MacNeill's sootywing) at Cibola National Wildlife Refuge from spring through fall 2006. Based on 1,620 observations, sootywings were observed most frequently flying in Atriplex lentiformis (Torr.) Wats. shrubs (largely mate searching by males), followed by dispersing, chasing or being chased, landing on flowers, basking (with wings open), perching (with wings closed), and ovipositing. Most sootywing behaviors correlated slightly better with sun position than with temperature, while landing on flowers and perching with wings closed correlated best with sun height. Sootywings were observed flying closer to the ground in A. lentiformis shrubs as the day progressed. They were observed feeding on the nectar of inflorescences of six plant species in six families, which changed through the season.
Elastic Mechanisms in the Locomotion of Vertebrates

Elastic mechanisms serve many functions in the locomotion of vertebrate animals. The ligamentum nuchae in the necks of ungulates gives some support to the head while allowing it to be lowered to the ground for feeding. Tendons in the distal parts of the legs of mammals save energy by stretching and recoiling in each step, enabling the animal to bounce along like a child on a pogo-stick. The same tendons aid jumping by recoiling rapidly like a catapult. An aponeurosis in the back serves as a spring in galloping, halting and reversing the swing of the legs. The elastic compliance of paw pads cushions impacts with the ground. The compliance of the tendons that move our fingers makes it easier for us to control the forces exerted by our fingers but harder to control their positions. The elastic properties of the diaphragm and abdominal wall may give resonant properties to the respiratory system, enabling running movements to drive breathing in some mammals. These and other possible functions of elastic mechanisms are reviewed.