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Presents a calculation for the reversible work of embryo formation of a new phase within a uniform macroscopic mother phase. Creation of an expression for the embryo formation; Extension of the Gibbsian formalism to noncritical nuclei; Introduction of a constraint preventing the transfer of matter between embryo and mother phase.

Elevated frequencies of malformations among the offspring of Baltic eelpout (Zoarces viviparus) have been observed in aquatic environments receiving high anthropogenic input suggesting that manmade chemicals could be the causative agent. However, causal links between exposure to chemicals and abnormal development have never been confirmed in laboratory experiments. The purpose of this study was to investigate if exposure to 17β-estradiol (E2) causes abnormal development in larvae of the viviparous eelpout. Wild female eelpout were collected immediately after fertilization and exposed to E2 concentrations ranging from 5.7 to 133 ng L-1 for 6 weeks in a flow through test system. The experiment shows that E2 concentrations of 53.6 and 133 ng L-1 cause severe abnormal development among eelpout embryos. Reduced amount of ovarian fluid and increased weight of the ovarian sac indicate disturbance of ovarian function. Female plasma concentrations of E2 and vitellogenin increase in a monotonic concentration--response relationship with significant induction in the low concentration range. Our findings support the plausibility that the abnormal development among eelpout embryos encountered in monitoring programs may actually be caused by exposure to chemicals in the environment. [ABSTRACT FROM AUTHOR]

In this work we compared the cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) contents of muscle, liver and placenta of gestating females of the viviparous shark Rhizoprionodon longurio and of muscle, liver and umbilical cord of their respective embryos. The higher values of the essential Cu and Zn were in embryonic or embryo-related tissues (placenta and umbilical cord). Maternal muscle and liver had the highest values of Pb and Cd, respectively. There were significant direct correlations between the Zn and Cd concentrations of placenta and umbilical cord, as well as between maternal muscle and embryonic livers for Pb and Cd, but the relation between these tissues was inverse in the case of Zn. All correlations between the metal content of embryonic tissues and size of the embryos were negative, suggesting an inverse relation between the rate of mother-to-embryo metal transfer and embryonic growth. [ABSTRACT FROM AUTHOR]

Numerous studies have evaluated the endocrine effects of UV filters in vertebrates, but little attention has been paid to their possible hormonal activity in invertebrates. We examined the effects of benzophenone-3 (BP-3), one of the most common sunscreen agents, in Chironomus riparius (Insecta), a reference organism in aquatic toxicology. Salivary glands from larvae were treated with either the hormone ecdysone or BP-3 to compare the response of endocrine genes. It was found that BP-3 elicits the same effects as the natural hormone activating the expression of a set of ecdysone responsive genes. BP-3 also activated the stress gene hsp70. Interestingly, similar effects have been confirmed in vivo in embryos. Moreover, BP-3 also altered embryogenesis delaying hatching. This is the first demonstration of hormonal activity of UV filters in invertebrates, showing a mode of action similar to ecdysteroid hormones. This finding highlights the potential endocrine disruptive effects of these emergent pollutants. [ABSTRACT FROM AUTHOR]

Background: Despite the importance of osmoprotectants, no previous in silico evaluation of high throughput data is available for higher plants. The present approach aimed at the identification and annotation of osmoprotectantrelated sequences applied to short transcripts from a soybean HT-SuperSAGE (High Throughput Super Serial Analysis of Gene Expression; 26-bp tags) database, and also its comparison with other transcriptomic and genomic data available from different sources. Methods: A curated set of osmoprotectants related sequences was generated using text mining and selected seed sequences for identification of the respective transcripts and proteins in higher plants. To test the efficiency of the seed sequences, these were aligned against four HT-SuperSAGE contrasting libraries generated by our group using soybean tolerant and sensible plants against water deficit, considering only differentially expressed transcripts (p ⩽ 0.05). Identified transcripts from soybean and their respective tags were aligned and anchored against the soybean virtual genome. Results: The workflow applied resulted in a set including 1,996 seed sequences that allowed the identification of 36 differentially expressed genes related to the biosynthesis of osmoprotectants [Proline (P5CS: 4, P5CR: 2), Trehalose (TPS1: 9, TPPB: 1), Glycine betaine (BADH: 4) and Myo-inositol (MIPS: 7, INPS1: 8)], also mapped in silico in the soybean genome (25 loci). Another approach considered matches using Arabidopsis full length sequences as seed sequences, and allowed the identification of 124 osmoprotectant-related sequences, matching ∼10.500 tags anchored in the soybean virtual chromosomes. Osmoprotectant-related genes appeared clustered in all soybean chromosomes, with higher density in some subterminal regions and synteny among some chromosome pairs. Conclusions: Soybean presents all searched osmoprotectant categories with some important members differentially expressed among the comparisons considered (drought tolerant or sensible vs. control; tolerant vs. sensible), allowing the identification of interesting candidates for biotechnological inferences. The identified tags aligned to corresponding genes that matched 19 soybean chromosomes. Osmoprotectant-related genes are not regularly distributed in the soybean genome, but clustered in some regions near the chromosome terminals, with some redundant clusters in different chromosomes indicating their involvement in previous duplication and rearrangements events. The seed sequences, transcripts and map represent the first transversal evaluation for osmoprotectant-related genes and may be easily applied to other plants of interest. [ABSTRACT FROM AUTHOR]

Metamorphosis is one of the most common, yet dramatic of life history strategies. In insects, complete metamorphosis with morphologically distinct larval stages arose from hemimetabolous ancestors that were more direct developing. Over the past century, several ideas have emerged that suggest the holometabolous pupa is developmentally homologous to the embryonic stages of the hemimetabolous ancestor. Other theories consider the pupal stage to be a modification of a hemimetabolous nymph. To address this question, we have isolated an ortholog of the pupal determinant, broad ( br), from the hemimetabolous milkweed bug and examined its role during embryonic development. We show that Oncopeltus fasciatus br ( Of’br) is expressed in two phases. The first occurs during germ band invagination and segmentation when Of’br is expressed ubiquitously in the embryonic tissues. The second phase of Of’br expression appears during the pronymphal phase of embryogenesis and persists through nymphal differentiation to decline just before hatching. Knock-down of Of’br transcripts results in defects that range from posterior truncations in the least-affected phenotypes to completely fragmented embryonic tissues in the most severe cases. Analysis of the patterning genes engrailed and hunchback reveal loss of segments and a failure in neural differentiation after Of’br depletion. Finally, we show that br is constitutively expressed during embyrogenesis of the ametabolous firebrat, Thermobia domestica. This suggests that br expression is prominent during embryonic development of ametabolous and hemimetabolous insects but was lost with the emergence of the completely metamorphosing insects. [ABSTRACT FROM AUTHOR]

Abstract: The present study was to evaluate the bioavailability of iron (Fe) fortified in parboiled rice grain, expressed as Fe uptake by Caco-2 cells after in vitro digestion. The bioavailability of Fe-fortified in the rice grain was closely and positively correlated with increasing concentrations of Fe in the grains of the three cultivars (r =0.96∗∗). The uptakes of the Fe-fortified in parboiled rice milled for 120s (34.2, 47.7 and 107ng ferritin mg protein−1 in three cultivars, respectively) were well above those of the unfortified raw (6.1, 4.9 and 5.7ng ferritin mg protein−1) or parboiled rice (4.7, 3.6 and 4.4ng ferritin mg protein−1), the high Fe rice line IR68144-2B-3-2-2 (4.0ng ferritin mg protein−1) and popular Jasmine rice cultivar KDML 105 (3.9ng ferritin mg protein−1). Increasing milling time and rinsing the Fe-fortified parboiled rice decreased Fe bioavailability, due to their negative effects on total Fe concentrations in the parboiled rice grains, but uptakes were still well above that of their unfortified raw or parboiled rice grains. Rinsing or washing the Fe-fortified and milled rice grains decreased the bioavailability to 85ng ferritin mg protein−1 in the YRF cultivar, compared to about 100ng ferritin mg protein−1 in its non-rinsed grains. Dilute acid-extractable (DAE) Fe was linearly, positively correlated with the uptake of Fe assessed by the in vitro digestion/Caco-2 cell technique (r =0.90∗∗), which can be used as a rapid method for optimizing levels of bioavailable Fe to be fortified in the parboiled rice by parboiled-rice mills if this Fe-fortification technique should be adopted in south and southeast Asia. [Copyright &y& Elsevier]

Abstract: Conventional measures aimed at tackling the energy and waste issues of island communities focus on technological solutions, such as the introduction of renewable energy sources. There exists a history of technology implementations on small islands that have failed because of a lack of continuing skills and financial resources needed for ongoing operation and maintenance. Despite these experiences, what has received little attention so far are measures aimed at achieving island-friendly solutions by reducing their material metabolism, for example, by recycling and re-use. The two case studies presented in this work show that conservation, efficiency and reductions of the overall material metabolism of economic activity can be as effective as purely technologically driven changes. Both case studies demonstrate exceptional sustainability performance in terms of material flow and greenhouse gas emissions. The income growth scenarios show that – from a sustainability point of view – increasing tourist yield rather than tourist numbers is preferable for coping with price hikes and a finite resource base, and is also more likely to keep within bounds the strain on the island''s people and infrastructure. [Copyright &y& Elsevier]

Abstract: Despite close structural similarity, the ferric and ferrous forms of cytochrome c differ greatly in terms of their ligand binding properties, stability, folding, and dynamics. The reduced heme iron binds diatomic ligands such as CO only under destabilizing conditions that promote weakening or disruption of native methionine–iron linkage. This makes CO a useful conformational probe for detecting partially structured states that cannot be observed in the absence of endogenous ligands. Heme absorbance, circular dichroism, and NMR were used to characterize the denaturant-induced unfolding equilibrium of ferrocytochrome c in the presence and in the absence of CO. In addition to the native state (N), which does not bind CO, and the unfolded CO complex (U-CO), a structurally distinct CO-bound form (M-CO) accumulates to high levels (∼75% of the population) at intermediate guanidine HCl concentrations. Comparison of the unfolding transitions for different conformational probes reveals that M-CO is a compact state containing a native-like helical core and regions of local disorder in the segment containing the native Met80 ligand and adjacent loops. Kinetic measurements of CO binding and dissociation under native, partially denaturing, and fully unfolded conditions indicate that a state M that is structurally analogous to M-CO is populated even in the absence of CO. The binding energy of the CO ligand lowers the free energy of this high-energy state to such an extent that it accumulates even under mildly denaturing equilibrium conditions. The thermodynamic and kinetic parameters obtained in this study provide a fully self-consistent description of the linked unfolding/CO binding equilibria of reduced cytochrome c. [Copyright &y& Elsevier]

Abstract: An increased aldosterone concentration can lead to a progression of heart diseases and to myocardial fibrosis. These fatal processes can be prevented by e.g. inhibiting the mineralocorticoid receptor (MR), which is nowadays part of a commonly applied standard therapy. Moreover, selective inhibition of aldosterone synthase (CYP11B2) is a straightforward goal whereby CYP11B1, a key enzyme in glucocorticoid biosynthesis exhibiting a high structure identity with CYP11B2 should not be inhibited. Therefore, effective test systems have been developed and rather potent and selective CYP11B2 compounds like SIAS-1 have been identified by our group. In addition to finding new inhibitors, we investigated which proteins are directly influenced by aldosterone focussing on non-genomic effects. Schizosaccharomyces pombe was chosen as a model organism, since this yeast does not contain nuclear steroid receptors, but many genes and regulatory mechanisms that are close to those of mammals. Besides creating a reference map for this organism, protein spots affected by aldosterone as well as deoxycorticosterone (DOC) and corticosterone have been identified. In case of aldosterone, a regulatory effect of proteins that are connected with structural proteins, signal cascades, osmoregulation and calcium pathway as well as to general metabolism have been discovered. DOC causes overlapping but also different effects compared with aldosterone. As shown exemplarily for GAPDH, the aldosterone-mediated effects in S. pombe can also be verified in mammalian cells. These and further investigations contribute to a deeper understanding of so-called non-genomic aldosterone effects. [Copyright &y& Elsevier]

Objectives: To compare the salivary receptor activator of NF- κB ligand (RANKL) and osteoprotegerin (OPG) concentrations in smokers versus non-smokers with chronic periodontitis. Material and Methods: Whole saliva samples were obtained from 67 untreated chronic periodontitis patients, of whom 34 were smokers, and from 44 maintenance patients, of whom 22 were smokers. Full-mouth clinical periodontal measurements were recorded. Saliva cotinine, sRANKL and OPG concentrations were determined by ELISA. Statistical analysis was performed using the Mann–Whitney U test, Bonferroni's correction for multiple comparisons and Spearman's correlations. Results: Untreated smokers exhibited significantly higher values of clinical periodontal recordings than untreated non-smokers (all p<0.05). Salivary cotinine level correlated with clinical attachment level ( p=0.023). Smoker versus non-smoker maintenance groups showed no significant differences in clinical parameters. There were significant differences in sRANKL and OPG concentrations between untreated and maintenance groups (all p<0.01). Salivary OPG concentration was significantly lower (all p<0.01) and the sRANKL/OPG ratio was higher (all p<0.01) in smokers than in non-smokers. OPG concentration correlated positively with probing depth, clinical attachment level and bleeding on probing (all p<0.005) and negatively with pack-year, and cotinine level ( p<0.05). Conclusion: Salivary RANKL and OPG concentrations are suggested to be affected by smoking as not only the untreated but also the treated smokers exhibited higher RANKL and lower OPG concentrations than non-smokers. [ABSTRACT FROM AUTHOR]

Noninvasive analysis of metabolism at the single cell level will have many applications in evaluating cellular physiology. One clinically relevant application would be to determine the metabolic activities of embryos produced through assisted reproduction. There is increasing evidence that embryos with greater developmental capacity have distinct metabolic profiles. One of the standard techniques for evaluating embryonic metabolism has been to evaluate consumption and production of several key energetic substrates (glucose, pyruvate, and lactate) using microfluorometric enzymatic assays. These assays are performed manually using constriction pipets, which greatly limits the utility of this system. Through multilayer soft-lithography, we have designed a microfluidic device that can perform these assays in an automated fashion. Following manual loading of samples and enzyme cocktail reagents, this system performs sample and enzyme cock-tail aliquotting, mixing of reagents, data acquisition, and data analysis without operator intervention. Optimization of design and operating regimens has resulted in the ability to perform serial measurements of glucose, pyruvate, and lactate in triplicate with submicroliter sample volumes within 5 mm. The current architecture allows for automated analysis of 10 samples and intermittent calibration over a 3 h period. Standard curves generated for each metabolite have correlation coefficients that routinely exceed 0.99. With the use of a standard epifluorescent microscope and CCD camera, linearity is obtained with metabolite concentrations in the low micromolar range (low femtomoles of total analyte). This system is inherently flexible, being easily adapted for any NAD(P)H-based assay and scaled up in terms of sample ports. Open source JAVA-based software allows for simple alterations in routine algorithms. Furthermore, this device can be used as a standalone device in which media samples are loaded or be integrated into microfluidic culture systems for in line, real time metabolic evaluation. With the improved throughput and flexibility of this system, many barriers to evaluating metabolism of embryos and single cells are eliminated. As a proof of principle, metabolic activities of single murine embryos were evaluated using this device. [ABSTRACT FROM AUTHOR]

A novel ferrocenyl anion receptor N, N, N, N-(dimethyl, ethyl, ferrocenecarboxylic amidodimethylene) ammonium fluoborate 2with multiple binding sites was synthesized. Its anion recognition behaviors were investigated by CV, 1H NMR and UV−vis spectrum. It was found that the combination of two interactions enforced the anion binding ability and the binding selectivity of 2to phosphate anion. The effects of scan rate on the CV curves of 2with phosphate were also investigated. In different scan rate, the CV curves kept stable which indicated the strong binding between 2and phosphate. According to relationships of peak potential, peak currents and scan rate of 2binding with phosphate, the kinetic parameters of electrode process such as diffusion coefficient Dapp, surface transfer coefficient αn α, and standard rate constant k0were calculated. [ABSTRACT FROM AUTHOR]

Summary: The gene clusters of several glycopeptides contain genes that encode COG2120 domain zinc-dependent N-acetylglucosaminyl deacetylases. Recently, a COG2120 protein encoded in the chloroeremomycin gene cluster, Cep15, has been postulated to possess nucleotidyltransferase activity. Here, we demonstrate that Cep15 possesses no catalytic activity and does not have a clear role in chloroeremomycin biosynthesis. This result strongly suggests that cep15 and bal2 are evolutionary artifacts and may be pseudogenes. Comparative sequence analysis with the closely related active Orf2∗ deacetylase (teicoplanin biosynthesis) reveals an asparagine in place of a metal-binding histidine in the “pseudo-active site” of Cep15. Substitution of this histidine by asparagine in Orf2∗ abolishes deacetylase activity. Remarkably, the Cep15 N164H mutant is an active deacetylase. To our knowledge, this is the first example of reactivating an ancestral enzymatic role for a bacterial protein by point mutagenesis. [Copyright &y& Elsevier]

Abstract: Concentrations of polychlorinated biphenyls (PCBs) in blubber of female common dolphins and harbour porpoises from the Atlantic coast of Europe were frequently above the threshold at which effects on reproduction could be expected, in 40% and 47% of cases respectively. This rose to 74% for porpoises from the southern North Sea. PCB concentrations were also high in southern North Sea fish. The average pregnancy rate recorded in porpoises (42%) in the study area was lower than in the western Atlantic but that in common dolphins (25%) was similar to that of the western Atlantic population. Porpoises that died from disease or parasitic infection had higher concentrations of persistent organic pollutants (POPs) than animals dying from other causes. Few of the common dolphins sampled had died from disease or parasitic infection. POP profiles in common dolphin blubber were related to individual feeding history while those in porpoises were more strongly related to condition. [Copyright &y& Elsevier]

Abstract  The common brushtail possum (Trichosurus vulpecula) is a generalist herbivore whose diet includes Eucalyptus leaves that are well defended by plant secondary metabolites (PSM) such as the terpene 1,8-cineole (cineole). We accustomed possums to a terpene-free diet, then challenged them with the addition of 2% cineole to the diet. Initially, there was a 50% reduction in total overnight food consumption associated with a marked decrease in the mass of the major feeding bout. After nine nights, however, cineole tolerance had developed as total food consumption had returned to the control amount. Compared to the control diet, the cineole diet was eaten in a larger number of smaller bouts, which were also eaten at a slower rate. The experiment was repeated with animals that had been accustomed to day-time feeding to take blood samples during feeding sessions. Feeding variables and blood concentration data for cineole were compared on the first and seventh day of the cineole diet. Although the total food consumed increased 2.5-fold after 7 days of the cineole diet, there was no increase in average blood cineole concentration, measured as the area under the concentration–time curve. This indicates that induction of liver enzymes resulted in greater pre-systemic metabolism of cineole and reduced bioavailability. The maximum tolerated blood concentration of cineole also increased, suggesting some adaptation of the central nervous system to the cineole aversive effects. This appears to be the first report in a vertebrate herbivore that consumption of a dietary PSM leads to metabolism induction and that this contributes to development of tolerance to the PSM. Overall, herbivores adapt to newly encountered dietary PSMs by immediate changes in feeding behavior followed by development of increased metabolism of PSM and probably diminished cellular responsiveness to effects. [ABSTRACT FROM AUTHOR]

A first palladium-catalyzed intramolecular diamination of unfunctionalized terminal alkenes has recently been reported. This study investigates the details of its mechanistic course based on NMR titration, kinetic measurements competition experiments, and deuterium labeling. It concludes a two-step procedure consisting of syn-aminopalladation with an unhigated palladium(ll) catalyst state followed by oxidation to palladium(IV) and subsequent C-N bond formation to give the final products as cyclic diamines. Related reactions employing sulfamides give rise to aminoalkoxy-functionalization of alkenes. This process was investigated employing deuterated alkenes and found to follow an identical mechanism where stereo-chemistry is concerned. It exemplifies the importance of cationic palladium(IV) intermediates prior to the final reductive elimination from palladium and proves that the nucelophile for this step stems from the immediate coordination sphere of the palladium(lV) precursor. These results have important implications for the general development of alkene 1,2-difunctionalization and for the individual processes of aminopalladation and palladium-catalyzed CaIkyI-N bond formation. [ABSTRACT FROM AUTHOR]

Three kinds of ampholites, i.e., 3-aminopropionic acid (NH2C2H4COOH), (2-aminoethyl)phosphonic acid (NH2C2H4PO3H2), and 2-aminoethane-1-sulfonic acid (NH2C2H4SO3H), were introduced into an epoxy group-containing polymer brush grafted onto a porous hollow-fiber membrane with a porosity of 70% and pore size of 0.36 m. The amphoteric group density of the hollow-fiber ranged from 0.50 to 0.72 mmol/g. Three kinds of proteins, i.e., lactoferrin (Lf), cytochrome c(Cyt c), and lysozyme (Ly), were captured by the amphoteric polymer brush during the permeation of the protein solution across the ampholite-immobilized porous hollow-fiber membrane. Multilayer binding of the protein to the amphoteric polymer brush, with a degree of multilayer binding of 3.3, 8.6, and 15 for Lf, Cyt c, and Ly, respectively, with the (2-aminoethyl)phosphonic acid-immobilized porous hollow-fiber membrane, was demonstrated with a negligible diffusional mass-transfer resistance of the protein to the ampholite immobilized. The 2-aminoethane-1-sulfonic acid-immobilized porous hollow-fiber membrane exhibited the lowest initial flux of the protein solution, 0.41 m/h at a transmembrane pressure of 0.1 MPa and 298 K, and the highest equilibrium binding capacity of the protein, e.g., 130 mg/g for lysozyme. Extension and shrinkage of the amphoteric polymer brushes were observed during the binding and elution of the proteins. [ABSTRACT FROM AUTHOR]

Abstract: Mandibular advancement devices (MADs) have emerged as a popular alternative for the treatment of sleep-disordered breathing. These devices bring the mandibula forward in order to increase upper airway (UA) volume and prevent total UA collapse during sleep. However, the precise mechanism of action appears to be quite complex and is not yet completely understood; this might explain interindividual variation in treatment success. We examined whether an UA model, that combines imaging techniques and computational fluid dynamics (CFD), allows for a prediction of the treatment outcome with MADs. Ten patients that were treated with a custom-made mandibular advancement device (MAD), underwent split-night polysomnography. The morning after the sleep study, a low radiation dose CT scan was scheduled with and without the MAD. The CT examinations allowed for a comparison between the change in UA volume and the anatomical characteristics through the conversion to three-dimensional computer models. Furthermore, the change in UA resistance could be calculated through flow simulations with CFD. Boundary conditions for the model such as mass flow rate and pressure distributions were obtained during the split-night polysomnography. Therefore, the flow modeling was based on a patient specific geometry and patient specific boundary conditions. The results indicated that a decrease in UA resistance and an increase in UA volume correlate with both a clinical and an objective improvement. The results of this pilot study suggest that the outcome of MAD treatment can be predicted using the described UA model. [Copyright &y& Elsevier]

Summary: Mucins in the gastrointestinal tract of Rhinolophus ferrumequinum were investigated by histochemistry and lectin histochemistry to evaluate morphofunctional variations of different regions and their possible physiological and evolutionary implications. Histochemical methods included periodic acid-Schiff (PAS), Alcian blue (AB) at pH 2.5 and 1.0 and high-iron-diamine AB pH 2.5. Binding of lectins Con A, DBA, WGA, LTA, LFA, PNA and SBA; LFA, PNA and SBA with prior sialidase treatment; and paradoxical Con A were evaluated. The oesophagus lacked glands. The stomach was divided into a short cardias, a wide fundus and a brief pylorus. The surface muciparous cells secreted sulpho- and sialomucins with N-acetylgalactosamine (GalNAc) residues, N-acetyllactosamine and (β1,4 N-acetylglucosamine) n chains. Towards the pylorus, N-acetylgalactosamine residues disappeared and acidity decreased. Cardiac glands, neck cells in the fundic glands, pyloric and duodenal Brunner''s glands all shared neutral, stable class-III mucins, mainly with N-acetylgalactosamine sequences. The intestine was divided into a duodenum, a jejuno-ileum and a short rectum. The goblet cells produced sulpho- and sialomucins with sialylated N-acetylgalactosamine sequences, (β1,4 N-acetylglucosamine) n and N-acetyllactosamine, whose sialylation increased towards the rectum. The main features of the mucins are probably associated with the requirements of fast absorption and food passage and in protection against mechanical and pathogenic injuries. [Copyright &y& Elsevier]

Effects of field application levels of wildfire control chemicals, Phos-Chek® G75-F (PC) and Silv-Ex® (SE), were examined on red-winged blackbird (Agelaius phoeniceus) embryos. Embryos were more sensitive to PC and SE when eggs were immersed for 10s at an early developmental stage (days 3–5 of incubation) than at a later stage (days 6–9 of incubation). The LC50 (concentration causing 50% mortality) for early stage embryos exposed to PC was 213.3g/L (slope=1.6; 95% confidence interval [CI]=129.1–326.1). The no observed effect concentration (NOEC) was below 135g PC/L, which caused a significant increase in embryonic mortality and represents the lowest field coverage level of 1gal/100feet2. The LC50 for early stage embryos exposed to SE was 19.8g/L (slope=1.5; 95% CI=11.7–52.2). Significant mortality was observed at 10g SE/L and marginal at 7.5g SE/L with an apparent NOEC around 5g SE/L. Neither chemical resulted in apparent developmental malformations. [Copyright &y& Elsevier]

BACKGROUND: The aim of the study was to determine the presence of interleukin (IL)-12, IL-15, IL-18 and p40 subunit of IL-12/IL-23 in follicular fluid from spontaneous cycles and the relation between the concentration of selected cytokines and IVF–embryo transfer outcome. METHODS: IVF–embryo transfer and enzyme immunoassay (EIA) (R&D Systems, Minneapolis, MN, USA and MBL, Nagoya, Japan) were used. RESULTS: Follicular fluid of women included in the IVF–embryo transfer procedure contained common p40 subunit of IL-12/IL-23 (median 70.1 pg/ml), IL-15 (median 1.3 pg/ml) and IL-18 (median 38.2 pg/ml). There was a significant negative correlation between follicular fluid concentrations of IL-15 and IL-18 (R = −0.392, P = 0.003). Significantly higher concentrations of common p40 subunit of IL-12/IL-23 (median 79.8 pg/ml) were found in the follicular fluid taken from follicles containing oocytes, when compared with those without an oocyte (median 44.5 pg/ml, P = 0.006). Patients who achieved clinical pregnancy had significantly decreased concentration of IL-15 (median 0.8 pg/ml) compared with patients without successful IVF–embryo transfer outcome (median 1.4 pg/ml, P = 0.047). CONCLUSION: Follicular fluid collected from spontaneous cycles contains detectable levels of p40 subunit of IL-12/IL-23, IL-15 and IL-18. Increased concentrations of p40 subunit of IL-12/IL-23 in follicles containing oocytes suggest an important role of this cytokine in reproduction. Possible negative value of IL-15 as a predictor of IVF–embryo transfer success remains to be determined. [ABSTRACT FROM AUTHOR]

An increasing number of human disorders have been linked to mutations in genes of the secretory pathway. The chemically induced zebrafish crusher variant results in malformed craniofacial skeleton, kinked pectoral fins and a short body length. By positional cloning, we identified a nonsense mutation converting leucine to a stop codon (L402X) in the sec23a gene, an integral component of the COPII complex, which is critical for anterograde protein trafficking between endoplasmic reticulum and Golgi apparatus. Zebrafish crusher mutants develop normally until the onset of craniofacial chondrogenesis. crusher chondrocytes accumulate proteins in a distended endoplasmic reticulum, resulting in severe reduction of cartilage extracellular matrix (ECM) deposits, including type II collagen. We demonstrate that the paralogous gene sec23b is also an essential component of the ECM secretory pathway in chondrocytes. In contrast, knockdown of the COPI complex does not hinder craniofacial morphogenesis. As SEC23A lesions cause the cranio-lenticulo-sutural dysplasia syndrome, crusher provides the first vertebrate model system that links the biology of endoplasmic reticulum to Golgi trafficking with a clinically relevant dysmorphology. [ABSTRACT FROM AUTHOR]

The article explores the putative adaptive advantage of continuous transmission within vivaparous gyrodactylids during colonization of new host sources in the U.S. Experimental results showed that infrapopulations of G. anisopharynx on C. paleatus and C. schwartzi had higher growth when C. ehrhardti showed an opposite trend, although differences in mean duration and maximum abundance were not statistically different. In addition, experimentation with C. paleatus and C. schwartzi support the hypothesis that continuous transmission in vivparous gyrodactylids enhances colonization success.

Mammalian skeletal myogenesis results in the differentiation of myoblasts to mature syncytial myotubes, a process regulated by an intricate genetic network of at least three protein families: muscle regulatory factors, E proteins, and Id proteins. MyoD, a key muscle regulatory factor, and its negative regulator Id1 have both been shown to be degraded by the ubiquitin-proteasome system. Using C2C12 cells and confocal fluorescence microscopy, we showed that MyoD and Id1 co-localize within the nucleus in proliferating myoblasts. In mature myotubes, in contrast, they reside in distinctive subcellular compartments, with MyoD within the nucleus and Id1 exclusively in the cytoplasm. Cellular abundance of Id1 was markedly diminished from the very onset of muscle differentiation, whereas MyoD abundance was reduced to a much lesser extent and only at the later stages of differentiation. These reductions in MyoD and Id1 protein levels seem to result from a change in the rate of protein synthesis rather than the rate of degradation. In vivo protein stability studies revealed that the rates of ubiquitin-proteasome-mediated MyoD and Id1 degradation are independent of myogenic differentiation state. Id1 and MyoD were both rapidly degraded, each with a t½ ≅ 1 h in myoblasts and in myotubes. Furthermore, relative protein synthesis rates for MyoD and Id1 were significantly diminished during myoblast to myotube differentiation. These results provide insight as to the interaction between MyoD and Id1 in the process of muscle differentiation and have implications for the involvement of the ubiquitin-proteasome-mediated protein degradation and protein synthesis in muscle differentiation and metabolism under abnormal and pathological conditions. [ABSTRACT FROM AUTHOR]

Several extracellular matrix (ECM)-degrading proteinases are hypothesised to play important roles during early mammalian development. In particular, urokinase-type plasminogen activator (uPA) and matrix metalloproteinase 9 (MMP-9) are expressed in peri-implantation mouse, sheep, and pig embryos and are implicated in the implantation process. These proteinases are not expressed in early (pre-blastocyst) mouse, sheep or pig embryos. The aim of this study was to establish the gene expression and proteolytic activity of uPA and MMP-9 in in vitro-produced (IVP) cow embryos. Using RT-PCR, mRNA transcripts for uPA and MMP-9 were detected during the first 7 days of development. To investigate the activity of these proteinases, conditioned media from various stages of development (days 2, 3, 4, 5 and 7) were assayed for uPA activity by chromogenic assay and MMP-9 activity by gelatin zymography. Both uPA and MMP-9 activities were detected in the media samples indicating the production and secretion of these proteinases. This pattern of proteinase expression is novel in comparison to the mouse where uPA and MMP-9 are only expressed from the blastocyst stage onwards. The results of this study suggest that these ECM proteinases have a role prior to implantation in the cow, in contrast to that exhibited by mouse, sheep and pig embryos. [ABSTRACT FROM AUTHOR]

Growth hormone (GH) may act as a local growth factor in early embryonic development, since GH- and GH-receptor (GHR) immunoreactivity is present in all tissues and most cells of embryonic chicks during organogenesis. However, as GHR-immunoreactivity could, alternatively, reflect the presence of GH-binding proteins (GHBPs) rather than authentic receptors linked to signal transduction mechanisms, GHR immunoreactivity may not be indicative of GH target sites. The possibility that GH may act as an autocrine or paracrine factor during embryogenesis was therefore assessed in the present study by determining the presence and cellular localization of mRNA for a GH-responsive gene. The mechanism of GH action involves the induction of a number of specific GH-response genes. In chickens a novel GH-responsive gene (GHRG-1) has been identified as a marker of GH action. In situ hybridization, using a 860 bp probe for GHRG-1 mRNA, demonstrated widespread expression of the GHRG-1 gene in embryonic tissues known to contain GH- and GHR-immunoreactivity (e.g. in the spinal cord, skin, heart, liver, muscle, bone and lung). GHRG-1 mRNA was not, however, present in all cells of each tissue. It was, furthermore, not present in subepithelial cells of the esophagus and bronchus and was lacking in many spinal cord ependyma, which are also known to lack GH immunoreactivity. These results therefore support the possibility that GH acts as an autocrine/paracrine factor during early chick embryogenesis, which was hitherto thought to be a ”growth-without-GH” syndrome. [ABSTRACT FROM AUTHOR]

The thiourea insecticide/acaricide diafenthiuron represents a biologically inactive propesticide that requires transformation into the active carbodiimide derivative. The carbodiimide inhibits mitochondrial respiration by selective and covalent binding to the proteolipid (8 kDa) of F [ABSTRACT FROM AUTHOR]

Chemical embryology was born in 1931 with the publication of Chemical Embryology by Joseph Needham. In the following two decades it became an innovative research project aiming at the description of the construction of the embryological structure and differentiation in biochemical terms. This research programme produced a vast amount of experimental evidence and theories on the chemical dynamics of the embryo: particularly chemical characterization of the zygote and the developing embryo, the chemical exchanges between the nucleus and the cytoplasm, the significance of subcellular structures, and the role and distribution of nucleic acids within the cell. From the 1950s on, a large part of these results came to be integrated into the empirical basis of molecular biology. However, the shift from chemical embryology to molecular embryology was not just a semantic shift but a deep theoretical change, produced by the introduction of a new model of scientific explanation, based on the transmission and expression of genetic information and opposed to the biochemical definition of life. [ABSTRACT FROM AUTHOR]

Presents research which analyzed the role of inositol 1,4,5-triphosphate (IP3)-induced Ca2+ release (IICR) on patterning of the embryonic body by producing monoclonal antibodies that inhibit IICR. Role of IP3; Injection of blocking antibodies into early Xenopus embryos; Correlation between IICR blocking potencies and ectopic dorsal axis induction frequency.

Focuses on transient changes in intracellular calcium that punctuate the cell cycle in various types of cells in culture and in early embryos. Correlation with cell-cycle events; Inducement of mitotic events by calcium injection into sea urchin embryos; Oscillation of the phosphoinositide messenger system during the early embryonic cell cycle in the sea urchin.

Enhancers are often located many tens of kilobases away from the promoter they regulate, sometimes residing closer to the promoter of a neighboring gene. How do they know which gene to activate? We have used homing P[en] constructs to study the enhancer-promoter communication at the engrailed locus. Here we show that engrailed enhancers can act over large distances, even skipping over other transcription units, choosing the engrailed promoter over those of neighboring genes. This specificity is achieved in at least three ways. First, early acting engrailed stripe enhancers exhibit promoter specificity. Second, a proximal promoter-tethering element is required for the action of the imaginal disc enhancer(s). Our data suggest that there are two partially redundant promoter-tethering elements. Third, the long-distance action of engrailed enhancers requires a combination of the engrailed promoter and sequences within or closely linked to the promoter proximal Polycomb-group response elements. These data show that multiple mechanisms ensure proper enhancer-promoter communication at the Drosophila engrailed locus. [ABSTRACT FROM AUTHOR]

Summary The effect of edoferon kappa A (E-KA), a non-specific immunomodulatory and anti-neoplastic chemical substance derived from the methyl form of salicylate (acetyl salicylic acid; ASA), on mammalian embryos was studied and compared to the effects of ASA. Rat embryos were cultured in vitro from 9.5 days of gestation for 48 h. E-KA (0.1–12.8 mg/ml) and ASA (0.1–0.6 mg/ml) were added to the whole rat serum. To investigate the interaction of these molecules with antioxidant agents, the lowest effective concentrations of E-KA (0.6 mg/ml) and ASA (0.3 mg/ml) for all parameters were added to the culture media in the presence of superoxide dismutase (SOD) (30 U/ml) or glutathione (0.5 μmol/ml). The growth and development of embryos was compared and each embryo was evaluated for the presence of any malformations. E-KA and ASA decreased growth and development in a concentration-responsive manner. There was also a concentration-related increase in overall dysmorphology (haematoma in the yolk sac and neural system, open neural tube, abnormal tail torsion and the absence of fore limb bud). There were no statistically significant differences between the control and embryos grown in the presence of 0.1–0.4 mg/ml E-KA, although the effects of ASA started at a concentration of 0.2 mg/ml. Embryos showed significant growth retardation in all scoring criteria and severe malformations when 0.5–3.2 mg/ml E-KA and 0.3–0.6 mg/ml ASA were added. When SOD was added, there was a significant decrease in the incidence of malformations and growth and developmental parameters were increased but this decrease never reached the control level. We concluded that E-KA has direct toxic effects on the developing embryo but at much higher concentrations than ASA, and the teratogenic effects of these molecules might be related to free oxygen radicals. [ABSTRACT FROM AUTHOR]