Antimicrobial activity of fractions and subfractions of Elaeagia utilis against microorganisms of importance in dental caries.

PubMed

Aldana, Jennyfer; Téllez, Nohemí; Gamboa, Fredy

2013-01-01

Dental caries is a multifactorial infectious disease that leads to the destruction of dental hard tissue. The main goal of research into medicinal plants is to seek compounds with antimicrobial activity for subsequent use in prevention strategies and control of infectious diseases. The aim of this study was to evaluate the antimicrobial activity of fractions and subfractions obtained from Elaeagia utilis against Streptococcus mutans, Streptococcus sobrinus and Lactobacillus acidophilus. The plant material was collected in the town of Alban (Cundinamarca, Colombia), which is located at an altitude of 2245 meters above sea level. Two extracts were obtained by cold maceration of E. utilis leaves in (a) petroleum ether extract and (b) ethanol extract. Fractions were obtained from the petroleum ether extract by column vacuum chromatography, and from the ethanol extract by continuous liquid/liquid partitioning. The antimicrobial activity of fractions and subfractions was evaluated by the well diffusion method. At a concentration of 10 mg/well, several fractions from both extracts showed antimicrobial activity against S. mutans, S. sobrinus and L. acidophilus. Among the ethanol extract fractions, the dichloromethane fraction had notably greater antimicrobial activity. It was sub-partitioned, yielding three subfractions with inhibitory activity, of which the most active was MeOH: H2O (Bp) with minimum inhibitory concentration 0.1 mg/well on the 3 study bacteria. Terpenes, sesquiterpenlactones and simple phenolic compounds were identified in it. In conclusion, this study shows the antimicrobial potential of fractions and subfractions obtained from extracts of E. utilis leaves against bacteria that are important in dental caries.

Seipin is required for converting nascent to mature lipid droplets

PubMed Central

Wang, Huajin; Becuwe, Michel; Housden, Benjamin E; Chitraju, Chandramohan; Porras, Ashley J; Graham, Morven M; Liu, Xinran N; Thiam, Abdou Rachid; Savage, David B; Agarwal, Anil K; Garg, Abhimanyu; Olarte, Maria-Jesus; Lin, Qingqing; Fröhlich, Florian; Hannibal-Bach, Hans Kristian; Upadhyayula, Srigokul; Perrimon, Norbert; Kirchhausen, Tomas; Ejsing, Christer S; Walther, Tobias C; Farese, Robert V

2016-01-01

How proteins control the biogenesis of cellular lipid droplets (LDs) is poorly understood. Using Drosophila and human cells, we show here that seipin, an ER protein implicated in LD biology, mediates a discrete step in LD formation—the conversion of small, nascent LDs to larger, mature LDs. Seipin forms discrete and dynamic foci in the ER that interact with nascent LDs to enable their growth. In the absence of seipin, numerous small, nascent LDs accumulate near the ER and most often fail to grow. Those that do grow prematurely acquire lipid synthesis enzymes and undergo expansion, eventually leading to the giant LDs characteristic of seipin deficiency. Our studies identify a discrete step of LD formation, namely the conversion of nascent LDs to mature LDs, and define a molecular role for seipin in this process, most likely by acting at ER-LD contact sites to enable lipid transfer to nascent LDs. DOI: http://dx.doi.org/10.7554/eLife.16582.001 PMID:27564575

How Messenger RNA and Nascent Chain Sequences Regulate Translation Elongation.

PubMed

Choi, Junhong; Grosely, Rosslyn; Prabhakar, Arjun; Lapointe, Christopher P; Wang, Jinfan; Puglisi, Joseph D

2018-06-20

Translation elongation is a highly coordinated, multistep, multifactor process that ensures accurate and efficient addition of amino acids to a growing nascent-peptide chain encoded in the sequence of translated messenger RNA (mRNA). Although translation elongation is heavily regulated by external factors, there is clear evidence that mRNA and nascent-peptide sequences control elongation dynamics, determining both the sequence and structure of synthesized proteins. Advances in methods have driven experiments that revealed the basic mechanisms of elongation as well as the mechanisms of regulation by mRNA and nascent-peptide sequences. In this review, we highlight how mRNA and nascent-peptide elements manipulate the translation machinery to alter the dynamics and pathway of elongation.

Relationship between lipoprotein subfraction cholesterol and residual risk for cardiovascular outcomes: A post hoc analysis of the AIM-HIGH trial.

PubMed

Toth, Peter P; Jones, Steven R; Slee, April; Fleg, Jerome; Marcovina, Santica M; Lacy, Megan; McBride, Ruth; Boden, William E

2018-03-09

The AIM-HIGH (Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides and Impact on Global Health Outcomes) trial failed to demonstrate incremental clinical benefit of extended-release niacin (ERN) in 3414 statin-treated patients with established cardiovascular (CV) disease who had low baseline levels of high-density lipoprotein cholesterol (HDL-C) as compared to placebo. A previous secondary analysis suggested that ERN provided outcome benefits in ERN-treated patients with high triglycerides (TGs; >200 mg/dL) and very low HDL-C (<32 mg/dL) at baseline. The current analysis sought to ascertain how changes in TG-enriched lipoproteins and HDL subfractions impact residual risk in the comparator treatment arms. We evaluated the relationship between niacin treatment, lipoproteins and their subfractions, and CV outcomes in a non-prespecified, post hoc analysis of the AIM-HIGH trial. Lipoprotein subfraction analysis was performed with zonal ultracentrifugation in 2457 AIM-HIGH participants at baseline and 1 year of treatment. Hazard ratios were estimated using Cox proportional hazards models for relationships between lipoproteins and the composite primary endpoint of CV death, myocardial infarction, acute coronary syndrome, ischemic stroke, or symptom-driven revascularization. Analyses were performed for the entire cohort and in participants with TGs > 200 mg/dL and HDL-C < 32 mg/dL. Apoprotein B-containing lipoproteins and their subfractions decreased significantly in both treatment arms but decreased more with ERN treatment. HDL-C and its subfractions increased significantly in both treatment groups, but more so in patients treated with ERN. For the entire study population, neither apoB- nor apoA1-containing lipoprotein subfractions predicted risk at baseline or at 1 year of follow-up. In the high TG and low HDL-C subgroup treated with placebo, changes at 1 year in HDL 2 -C, total cholesterol/HDL 2 -C, and non-HDL-C/HDL 2 -C may be

Anticancer Activity of Chloroform Extract and Sub-fractions of Nepeta deflersiana on Human Breast and Lung Cancer Cells: An In vitro Cytotoxicity Assessment.

PubMed

Al-Oqail, Mai M; Al-Sheddi, Ebtesam S; Siddiqui, Maqsood A; Musarrat, Javed; Al-Khedhairy, Abdulaziz A; Farshori, Nida N

2015-10-01

Cancer is one of the major causes of death worldwide. The plant-derived natural products have received considerable attention in recent years due to their diverse pharmacological properties including anticancer effects. Nepeta deflersiana (ND) is used in the folk medicine as antiseptic, carminative, antimicrobial, antioxidant, and for treating rheumatic disorders. However, the anticancer activity of ND chloroform extract has not been explored so far. The present study was aimed to investigate the anticancer activities of chloroform Nepeta deflersiana extract and various sub-fractions (ND-1-ND-15) of ND against human breast cancer cells (MCF-7) and human lung cancer cells (A-549). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and neutral red uptake assays, and cellular morphological alterations using phase contrast light microscope were studied. Cells were exposed with 10-1000 μg/ml of sub-fractions of ND for 24 h. Results showed that selected sub-fractions of the chloroform extract significantly reduced the cell viability of MCF-7 and A-549 cells, and altered the cellular morphology in a concentration-dependent manner. Among the sub-fractions, ND-10 fraction showed relatively higher cytotoxicity compared to other fractions whereas, ND-1 did not cause any cytotoxicity even at higher concentrations. The A-549 cells were found to be more sensitive to growth inhibition by all the extracts as compared to the MCF-7 cells. The present study provides preliminary screening of anticancer activities of chloroform extract and sub-fractions of ND, which can be further used for the development of a potential therapeutic anticancer agent. Nepeta deflersiana extract exhibit cytotoxicity and altered the cellular morphology. Sub-fractions of the chloroform extract of Nepeta deflersiana reduced the cell viability of MCF-7 and A-549 cells. Among the sub-fractions, ND-10 fraction showed relatively higher cytotoxicity. The A-549 cells were found to be more sensitive

Pervasive Targeting of Nascent Transcripts by Hfq.

PubMed

Kambara, Tracy K; Ramsey, Kathryn M; Dove, Simon L

2018-05-01

Hfq is an RNA chaperone and an important post-transcriptional regulator in bacteria. Using chromatin immunoprecipitation coupled with high-throughput DNA sequencing (ChIP-seq), we show that Hfq associates with hundreds of different regions of the Pseudomonas aeruginosa chromosome. These associations are abolished when transcription is inhibited, indicating that they reflect Hfq binding to transcripts during their synthesis. Analogous ChIP-seq analyses with the post-transcriptional regulator Crc reveal that it associates with many of the same nascent transcripts as Hfq, an activity we show is Hfq dependent. Our findings indicate that Hfq binds many transcripts co-transcriptionally in P. aeruginosa, often in concert with Crc, and uncover direct regulatory targets of these proteins. They also highlight a general approach for studying the interactions of RNA-binding proteins with nascent transcripts in bacteria. The binding of post-transcriptional regulators to nascent mRNAs may represent a prevalent means of controlling translation in bacteria where transcription and translation are coupled. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Comparative study of the effects of solid-state fermentation with three filamentous fungi on the total phenolics content (TPC), flavonoids, and antioxidant activities of subfractions from oats (Avena sativa L.).

PubMed

Cai, Shengbao; Wang, Ou; Wu, Wei; Zhu, Songjie; Zhou, Feng; Ji, Baoping; Gao, Fengyi; Zhang, Di; Liu, Jia; Cheng, Qian

2012-01-11

The aim of present work was to investigate the effect of solid-state fermentation with filamentous fungi (Aspergillus oryzae var. effuses, Aspergillus oryzae, and Aspergillus niger) on total phenolics content (TPC), flavonoids, and antioxidant activities of four subfractions of oat, namely, n-hexane, ethyl acetate (EA), n-butanol, and water, and compare them to their corresponding subfractions of unfermented oat. The TPC and total flavonoids increased dramatically, especially in EA subfractions (p < 0.05). The levels of antioxidant activity of subfractions were also significantly enhanced (p < 0.05). The highest antioxidant activities were also found in the EA subfractions. The polyphenols in EA were analyzed by high-performance liquid chromatography at 280 nm. Most polyphenols were increased remarkably, especially ferulic and caffeic acids. There was a clear correlation between the TPC and antioxidant activity. In conclusion, fungi fermentation is a potential bioprocess for increasing the TPC, flavonoids, and antioxidant activities of oat-based food.

Evaluation of Antiradical and Anti-Inflammatory Activities of Ethyl Acetate and Butanolic Subfractions of Agelanthus dodoneifolius (DC.) Polhill & Wiens (Loranthaceae) Using Equine Myeloperoxidase and Both PMA-Activated Neutrophils and HL-60 Cells

PubMed Central

Boly, Rainatou; Franck, Thierry; Kohnen, Stephan; Lompo, Marius; Guissou, Innocent Pierre; Dubois, Jacques; Serteyn, Didier; Mouithys-Mickalad, Ange

2015-01-01

The ethyl acetate and n-butanolic subfractions of Agelanthus dodoneifolius were investigated for their antioxidant and antimyeloperoxidase (MPO) activities. The reactive oxygen species (ROS) generation was assessed by lucigenin-enhanced chemiluminescence (CL) and dichlorofluorescein- (DCF-) induced fluorescence techniques from phorbol myristate acetate- (PMA-) stimulated equine neutrophils and human myeloid cell line HL-60, respectively. In parallel, the effects of the tested subfractions were evaluated on the total MPO release by stimulated neutrophils and on the specific MPO activity by means of immunological assays. The results showed the potent activity of the butanolic subfraction, at least in respect of the chemiluminescence test (IC50 = 0.3 ± 0.1 µg/mL) and the ELISA and SIEFED assays (IC50 = 2.8 ± 1.2 µg/mL and 1.3 ± 1.0 µg/mL), respectively. However, the ethyl acetate subfraction was found to be the most potent in the DCF assay as at the highest concentration, DCF fluorescence intensity decreases of about 50%. Moreover, we demonstrated that the ethyl acetate subfraction was rich in catechin (16.51%) while it was not easy to identify the main compounds in the butanolic subfraction using the UPLC-MS/MS technique. Nevertheless, taken together, our results provide evidence that Agelanthus dodoneifolius subfractions may represent potential sources of natural antioxidants and of antimyeloperoxidase compounds. PMID:25821497

Purification of high-molecular-weight subfraction from porcine skin inhibiting proliferation of A431 human carcinoma epidermoid cells.

PubMed

Belova, O V; Sergienko, V I; Arion, V Ya; Lukanidina, T A; Moskvina, S N; Zimina, I V; Borisenko, G G; Lutsenko, G V; Grechikhina, M V; Kovaleva, E V; Klyuchnikova, Zh I

2014-07-01

Subfraction with a molecular weight >250 kDa isolated from porcine skin and inhibiting the proliferation of A431 human carcinoma epidermoid cells was purified by DEAE 32 anion exchange chromatography with NaCl concentration step-gradient. The effects of the initial subfraction and fractions obtained by separation in DEAE 32 on the proliferation of A431 human carcinoma epidermoid cells were studied in vitro in two tests (MTT and fluorescent test). The more sensitive fluorescent test showed the highest inhibitory activity of fraction No. 2 released from the column at 0.15 M NaCl. One major protein component and a series of minor protein components were detected in this fraction by vertical PAAG-SDS electrophoresis.

Cotranslational structure acquisition of nascent polypeptides monitored by NMR spectroscopy.

PubMed

Eichmann, Cédric; Preissler, Steffen; Riek, Roland; Deuerling, Elke

2010-05-18

The folding of proteins in living cells may start during their synthesis when the polypeptides emerge gradually at the ribosomal exit tunnel. However, our current understanding of cotranslational folding processes at the atomic level is limited. We employed NMR spectroscopy to monitor the conformation of the SH3 domain from alpha-spectrin at sequential stages of elongation via in vivo ribosome-arrested (15)N,(13)C-labeled nascent polypeptides. These nascent chains exposed either the entire SH3 domain or C-terminally truncated segments thereof, thus providing snapshots of the translation process. We show that nascent SH3 polypeptides remain unstructured during elongation but fold into a compact, native-like beta-sheet assembly when the entire sequence information is available. Moreover, the ribosome neither imposes major conformational constraints nor significantly interacts with exposed unfolded nascent SH3 domain moieties. Our data provide evidence for a domainwise folding of the SH3 domain on ribosomes without significant population of folding intermediates. The domain follows a thermodynamically favorable pathway in which sequential folding units are stabilized, thus avoiding kinetic traps during the process of cotranslational folding.

DYNAMICS OF NASCENT AND ACTIVE ZONE ULTRASTRUCTURE AS SYNAPSES ENLARGE DURING LTP IN MATURE HIPPOCAMPUS

PubMed Central

Bell, Maria Elizabeth; Bourne, Jennifer N.; Chirillo, Michael A.; Mendenhall, John M.; Kuwajima, Masaaki; Harris, Kristen M.

2014-01-01

Nascent zones and active zones are adjacent synaptic regions that share a postsynaptic density, but nascent zones lack the presynaptic vesicles found at active zones. Here dendritic spine synapses were reconstructed through serial section electron microscopy (3DEM) and EM tomography to investigate nascent zone dynamics during long-term potentiation (LTP) in mature rat hippocampus. LTP was induced with theta-burst stimulation and comparisons were made to control stimulation in the same hippocampal slices at 5 minutes, 30 minutes, and 2 hours post-induction and to perfusion-fixed hippocampus in vivo. Nascent zones were present at the edges of ~35% of synapses in perfusion-fixed hippocampus and as many as ~50% of synapses in some hippocampal slice conditions. By 5 minutes, small dense core vesicles known to transport active zone proteins moved into more presynaptic boutons. By 30 minutes, nascent zone area decreased without significant change in synapse area, suggesting that presynaptic vesicles were recruited to pre-existing nascent zones. By 2 hours, both nascent and active zones were enlarged. Immunogold labeling revealed that glutamate receptors can be found in nascent zones; however, average distances from nascent zones to docked presynaptic vesicles ranged from 170±5 nm in perfusion-fixed hippocampus to 251±4 nm at enlarged synapses by 2 hours during LTP. Prior stochastic modeling suggests that falloff in glutamate concentration reduces the probability of glutamate receptor activation from 0.4 at the center of release to 0.1 just 200 nm away. Thus, conversion of nascent zones to functional active zones likely requires the recruitment of presynaptic vesicles during LTP. PMID:25043676

Characterization of a novel isoform of alpha-nascent polypeptide-associated complex as IgE-defined autoantigen.

PubMed

Mossabeb, Roschanak; Seiberler, Susanne; Mittermann, Irene; Reininger, Renate; Spitzauer, Susanne; Natter, Susanne; Verdino, Petra; Keller, Walter; Kraft, Dietrich; Valenta, Rudolf

2002-10-01

The nascent polypeptide-associated complex is required for intracellular translocation of newly synthesized polypeptides in eukaryotic cells. It may also act as a transcriptional coactivator in humans and various eukaryotic organisms and binds to nucleic acids. Recently, we provided evidence that a component of nascent polypeptide-associated complex, alpha-nascent polypeptide-associated complex, represents an IgE-reactive autoantigen for atopic dermatitis patients. By oligonucleotide screening we isolated a complete cDNA coding for a so far unknown alpha-nascent polypeptide-associated complex isoform from a human epithelial cDNA library. Southern blot hybridization experiments provided further evidence that alpha-nascent polypeptide-associated complex is encoded by a gene family. Recombinant alpha-nascent polypeptide-associated complex was expressed in Escherichia coli as a soluble, His-tagged protein, and purified via nickel affinity chromatography. By circular dichroism analysis it is demonstrated that purified recombinant alpha-nascent polypeptide-associated complex represents a folded protein of mixed alpha-helical and beta-sheet conformation with unusual high thermal stability and remarkable refolding capacity. Complete recombinant alpha-nascent polypeptide-associated complex (215 amino acids) and its 86 amino acid C-terminal fragment specifically bound IgE autoantibodies. Recombinant alpha-nascent polypeptide-associated complex also inhibited IgE binding to natural alpha-nascent polypeptide-associated complex, demonstrating the presence of common IgE epitopes between the recombinant and natural protein. Furthermore, recombinant alpha-nascent polypeptide-associated complex induced specific lymphoproliferative responses in peripheral blood mononuclear cells of a sensitized atopic dermatitis patient. As has been proposed for environmental allergens it is possible that T cell responses to IgE-defined autoantigens may contribute to the chronic skin manifestations

Lipoprotein Subfractions in Metabolic Syndrome and Obesity: Clinical Significance and Therapeutic Approaches

PubMed Central

Nikolic, Dragana; Katsiki, Niki; Montalto, Giuseppe; Isenovic, Esma R.; Mikhailidis, Dimitri P.; Rizzo, Manfredi

2013-01-01

Small, dense low density lipoprotein (sdLDL) represents an emerging cardiovascular risk factor, since these particles can be associated with cardiovascular disease (CVD) independently of established risk factors, including plasma lipids. Obese subjects frequently have atherogenic dyslipidaemia, including elevated sdLDL levels, in addition to elevated triglycerides (TG), very low density lipoprotein (VLDL) and apolipoprotein-B, as well as decreased high density lipoprotein cholesterol (HDL-C) levels. Obesity-related co-morbidities, such as metabolic syndrome (MetS) are also characterized by dyslipidaemia. Therefore, agents that favourably modulate LDL subclasses may be of clinical value in these subjects. Statins are the lipid-lowering drug of choice. Also, anti-obesity and lipid lowering drugs other than statins could be useful in these patients. However, the effects of anti-obesity drugs on CVD risk factors remain unclear. We review the clinical significance of sdLDL in being overweight and obesity, as well as the efficacy of anti-obesity drugs on LDL subfractions in these individuals; a short comment on HDL subclasses is also included. Our literature search was based on PubMed and Scopus listings. Further research is required to fully explore both the significance of sdLDL and the efficacy of anti-obesity drugs on LDL subfractions in being overweight, obesity and MetS. Improving the lipoprotein profile in these patients may represent an efficient approach for reducing cardiovascular risk. PMID:23507795

Genetic associations with lipoprotein subfraction measures differ by ethnicity in the multi-ethnic study of atherosclerosis (MESA)

USDA-ARS?s Scientific Manuscript database

A recent genome-wide association study associated 62 single nucleotide polymorphisms (SNPs) from 43 genomic loci, with fasting lipoprotein subfractions in European–Americans (EAs) at genome-wide levels of significance across three independent samples. Whether these associations are consistent across...

Stable isotopic carbon composition of apples and their subfractions--juice, seeds, sugars, and nonvolatile acids.

PubMed

Lee, H S; Wrolstad, R E

1988-01-01

The 13C:12C ratios of 8 authentic apple juice samples and their subfractions were determined by mass spectrometry. Apples from Argentina, Mexico, New Zealand, and the United States were processed into juice; pulp was collected from the milled fruit and seeds were collected from the press-cake. Sugars, nonvolatile acids, and phenolics were isolated from the juice by treatment with ion-exchange resins and polyvinylpyrrolidone (PVPP). The mean value for all juice samples was -24.2% which is close to the values reported by other investigators. Juice from apples grown in Argentina, Mexico, and New Zealand did not differ from U.S. samples. The isotopic composition of the subfractions ranged from -22.0 to -31.0%. The values for the pulp were essentially the same as for juice. The sugar fraction was slightly less negative than the juice; the nonvolatile acid and phenolic fractions were more negative. The levels of nonvolatile acids and phenolics in apple juice are low, however, so these compounds contribute little to overall delta 13C values in juice.

A law of iterated logarithm for the subfractional Brownian motion and an application.

PubMed

Qi, Hongsheng; Yan, Litan

2018-01-01

Let [Formula: see text] be a sub-fractional Brownian motion with Hurst index [Formula: see text]. In this paper, we give a local law of the iterated logarithm of the form [Formula: see text] almost surely, for all [Formula: see text], where [Formula: see text] for [Formula: see text]. As an application, we introduce the [Formula: see text]-variation of [Formula: see text] driven by [Formula: see text] [Formula: see text] with [Formula: see text].

Experimental Investigation of Nascent Soot Physical Properties and The Influence on Particle Morphology and Growth

NASA Astrophysics Data System (ADS)

Lieb, Sydnie Marie

Soot released to the atmosphere is a dangerous pollutant for human health and the environment. Understanding the physical properties and surface properties of these particles is important to properly explaining the growth of soot particles in flames as well as their interactions with other particles and gases in the environment. Particles below 15 nm in diameter, nascent soot particles, dominate the early growth stages of soot formation; previously these particles were characterized as hard graphitic spheres. New evidence derived from the current dissertation work, to a large extent, challenges this prior characterization. This dissertation study begins by revisiting the use of atomic force microscope (AFM) as a tool to investigate the structural properties of nascent soot. The impact of tip artifacts, which are known to complicate measurements of features below 10 nm in diameter, are carefully considered so as to provide a concise interpretation of the morphology of nascent soot as seen by AFM. The results of the AFM morphology collaborate with earlier photo- and thermal-fragmentation particle mass spectrometry and Fourier transform infrared spectroscopy that nascent soot is not a graphitized carbon material and that they are not spherical. Furthermore, phase mode imaging is introduced as a method to investigate the physical properties of nascent soot particles in a greater detail and finer resolution. The helium ion microscope (HIM) has been identified as a useful technique for the imaging of nascent soot. Using this imaging method nascent soot particles were imaged with a high resolution that had not been obtained by prior techniques. The increased contrast provides a closer look at the nascent soot particles and further suggested that these particles are not as structurally homogeneous as previously thought. Geometric shape analysis was performed to characterize the particles in terms of sphericity, circularity, and fractal dimension. The geometric analysis

Nascent-Seq reveals novel features of mouse circadian transcriptional regulation

PubMed Central

Menet, Jerome S; Rodriguez, Joseph; Abruzzi, Katharine C; Rosbash, Michael

2012-01-01

A substantial fraction of the metazoan transcriptome undergoes circadian oscillations in many cells and tissues. Based on the transcription feedback loops important for circadian timekeeping, it is commonly assumed that this mRNA cycling reflects widespread transcriptional regulation. To address this issue, we directly measured the circadian dynamics of mouse liver transcription using Nascent-Seq (genome-wide sequencing of nascent RNA). Although many genes are rhythmically transcribed, many rhythmic mRNAs manifest poor transcriptional rhythms, indicating a prominent contribution of post-transcriptional regulation to circadian mRNA expression. This analysis of rhythmic transcription also showed that the rhythmic DNA binding profile of the transcription factors CLOCK and BMAL1 does not determine the transcriptional phase of most target genes. This likely reflects gene-specific collaborations of CLK:BMAL1 with other transcription factors. These insights from Nascent-Seq indicate that it should have broad applicability to many other gene expression regulatory issues. DOI: http://dx.doi.org/10.7554/eLife.00011.001 PMID:23150795

Nascent RNA kinetics: Transient and steady state behavior of models of transcription

NASA Astrophysics Data System (ADS)

Choubey, Sandeep

2018-02-01

Regulation of transcription is a vital process in cells, but mechanistic details of this regulation still remain elusive. The dominant approach to unravel the dynamics of transcriptional regulation is to first develop mathematical models of transcription and then experimentally test the predictions these models make for the distribution of mRNA and protein molecules at the individual cell level. However, these measurements are affected by a multitude of downstream processes which make it difficult to interpret the measurements. Recent experimental advancements allow for counting the nascent mRNA number of a gene as a function of time at the single-inglr cell level. These measurements closely reflect the dynamics of transcription. In this paper, we consider a general mechanism of transcription with stochastic initiation and deterministic elongation and probe its impact on the temporal behavior of nascent RNA levels. Using techniques from queueing theory, we derive exact analytical expressions for the mean and variance of the nascent RNA distribution as functions of time. We apply these analytical results to obtain the mean and variance of nascent RNA distribution for specific models of transcription. These models of initiation exhibit qualitatively distinct transient behaviors for both the mean and variance which further allows us to discriminate between them. Stochastic simulations confirm these results. Overall the analytical results presented here provide the necessary tools to connect mechanisms of transcription initiation to single-cell measurements of nascent RNA.

Topographic control on the nascent Mediterranean outflow

NASA Astrophysics Data System (ADS)

Gasser, M.; Pelegrí, J. L.; Nash, J. D.; Peters, H.; García-Lafuente, J.

2011-12-01

Data collected during a 12-day cruise in July 2009 served to examine the structure of the nascent Mediterranean Outflow Water (MOW) immediately west of the Espartel Sill, the westernmost sill in the Strait of Gibraltar. The MOW is characterized by high salinities (>37.0 and reaching 38.3) and high velocities (exceeding 1 m s-1 at 100 m above the seafloor), and follows a submerged valley along a 30 km stretch, the natural western extension of the strait. It is approx. 150 m thick and 10 km wide, and experiences a substantial drop from 420 to 530 m over a distance of some 3 km between two relatively flat regions. Measurements indicate that the nascent MOW behaves as a gravity current with nearly maximal traveling speed; if this condition is maintained, then the maximum MOW velocity would decrease slowly with distance from the Espartel Sill, remaining significantly high until the gravity current excess density is only a small fraction of its original value. The sharp pycnocline between the Mediterranean and the overlying North Atlantic Central waters is dynamically unstable, particularly where the flow interacts with the 100 m decrease in bottom depth. Here, subcritical gradient Richardson numbers coincide with the development of large interfacial undulations and billows. The very energetic downslope flow is likely responsible for the development of a narrow V-shaped channel downstream of the seafloor drop along the axis of the submerged valley, this probably being the very first erosional scour produced by the nascent MOW. The coincidence of subcritical gradient Richardson numbers with relatively high turbidity values above the channel flanks suggests it may be undergoing upstream erosion.

High-density lipoprotein-cholesterol, its subfractions, and responses to exercise training are dependent on endothelial lipase genotype.

PubMed

Halverstadt, Amy; Phares, Dana A; Ferrell, Robert E; Wilund, Kenneth R; Goldberg, Andrew P; Hagberg, James M

2003-11-01

Plasma high-density lipoprotein cholesterol (HDL-C) levels are an important independent risk factor for cardiovascular disease (CVD) that can be modified through exercise training. However, levels of HDL-C and its subfractions and their response to standardized exercise training are highly variable among individuals. Such variability suggests that levels of HDL-C, its subfractions, and their response to exercise training may be influenced by genetic variation and the interaction of that genetic variation with physical activity. The endothelial lipase gene (LIPG) may influence HDL-C metabolism and has several recently identified genetic variants. We hypothesized that the LIPG Thr111Ile polymorphism would be associated with variation in HDL-C levels and its subfractions and their response to exercise training. Eighty-three sedentary, healthy 50- to 75-year-old subjects were weight-maintained on an American Heart Association Step 1 Diet and then studied before and after aerobic exercise training. Sample size varied according to outcome measure as complete data was not available for all subjects. Initial age, body composition, and maximum oxygen consumption (V02max) did not differ between LIPG genotype groups (CC, n=41 to 44; CT/TT, n=37 to 39). Initial total cholesterol, low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) levels were not significantly different between groups. The CT/TT group had lower initial HDL(2NMR)-C (12 +/- 1.0 v 17 +/- 1.1 mg/dL; P =.002) and integrated HDL(1,2NMR)-C (13 +/- 1.0 v 18 +/- 1.1 mg/dL; P=.002) levels and somewhat higher initial levels of integrated HDL(3,4,5)-C (31 +/- 2.2 v 25 +/- 2.3 mg/dL; P=.06). With exercise training, Vo2max increased, and body weight, total body fat, and visceral adipose tissue decreased similarly in both groups. With training, HDL-C levels increased twice as much (4.4 +/- 0.8 v 1.9 +/- 0.9 mg/dL; P=.04), HDL3-C levels increased almost 2-fold greater (3.8 +/- 0.7 v 2.2 +/- 0.6 mg/dL; P=.07

Entrepreneurial Identity and Role Expectations in Nascent Entrepreneurship

ERIC Educational Resources Information Center

Lundqvist, Mats; Middleton, Karen Williams; Nowell, Pamela

2015-01-01

Entrepreneurship has been defined as an individual?new value creation dialogic. To study how entrepreneurial identity evolves, this article, drawing on entrepreneurial learning theory, adds an entrepreneurial role expectations dialogic. Longitudinal evidence from nascent entrepreneurs working in venture teams on invention disclosures offers an…

Effect of insulin analog initiation therapy on LDL/HDL subfraction profile and HDL associated enzymes in type 2 diabetic patients.

PubMed

Aslan, Ibrahim; Kucuksayan, Ertan; Aslan, Mutay

2013-04-24

Insulin treatment can lead to good glycemic control and result in improvement of lipid parameters in type 2 diabetic patients. This study was designed to evaluate the effect of insulin analog initiation therapy on low-density lipoprotein (LDL)/ high-density lipoprotein (HDL) sub-fractions and HDL associated enzymes in type 2 diabetic patients during early phase. Twenty four type 2 diabetic patients with glycosylated hemoglobin (HbA1c) levels above 10% despite ongoing combination therapy with sulphonylurea and metformin were selected. Former treatment regimen was continued for the first day followed by substitution of sulphonylurea therapy with different insulin analogs (0.4 U/kg/day) plus metformin. Glycemic profiles were determined over 72 hours by continuous glucose monitoring system (CGMS) and blood samples were obtained from all patients at 24 and 72 hours. Plasma levels of cholesteryl ester transfer protein (CETP), lecithin-cholesterol acyltransferase (LCAT), apolipoprotein B (apoB) and apolipoprotein A-1 (apoA-I) were determined by enzyme-linked immunosorbent assay (ELISA). Measurement of CETP and LCAT activity was performed via fluorometric analysis. Paraoxonase (PON1) enzyme activity was assessed from the rate of enzymatic hydrolysis of phenyl acetate to phenol formation. LDL and HDL subfraction analysis was done by continuous disc polyacrylamide gel electrophoresis. Mean blood glucose, total cholesterol (TC), triglyceride (TG) and very low-density lipoprotein cholesterol (VLDL-C) levels were significantly decreased while HDL-C levels were significantly increased after insulin treatment. Although LDL-C levels were not significantly different before and after insulin initiation therapy a significant increase in LDL-1 subgroup and a significant reduction in atherogenic LDL-3 and LDL-4 subgroups were observed. Insulin analog initiation therapy caused a significant increase in HDL-large, HDL- intermediate and a significant reduction in HDL-small subfractions

Accelerators as Authentic Training Experiences for Nascent Entrepreneurs

ERIC Educational Resources Information Center

Miles, Morgan P.; de Vries, Huibert; Harrison, Geoff; Bliemel, Martin; de Klerk, Saskia; Kasouf, Chick J.

2017-01-01

Purpose: The purpose of this paper is to address the role of accelerators as authentic learning-based entrepreneurial training programs. Accelerators facilitate the development and assessment of entrepreneurial competencies in nascent entrepreneurs through the process of creating a start-up venture. Design/methodology/approach: Survey data from…

Oxidation-labile subfraction of human plasma low density lipoprotein isolated by ion-exchange chromatography.

PubMed

Shimano, H; Yamada, N; Ishibashi, S; Mokuno, H; Mori, N; Gotoda, T; Harada, K; Akanuma, Y; Murase, T; Yazaki, Y

1991-05-01

We isolated subfractions of human plasma low density lipoprotein (LDL) using ion-exchange chromatography. Plasma LDL from normolipidemic subjects were applied to a DEAE Sepharose 6B column. After elution of the bulk of LDL at 150 mM NaCl (the major fraction), the residual LDL was eluted at 500 mM NaCl and designated as the minor fraction. The minor fraction, only less than 1% of total LDL, tended to be somewhat similar in certain properties to oxidized LDL, e.g., an increased negative charge, higher protein/cholesterol ratio, and a higher flotation density than native LDL. These results were consistent with data reported by Avogaro et al. (1988. Arteriosclerosis. 8: 79-87). However, assays of 125I-labeled LDL binding activity for LDL receptors equal to that of the major fraction. Incorporation of [14C]oleate into cholesteryl ester [acyl-CoA:cholesterol acyltransferase (ACAT) activity] in mouse peritoneal macrophages incubated with the minor fraction was only slightly greater than that with the major fraction. Incubation of the minor fraction with 0.5 microM Cu2+ caused a remarkable stimulation of ACAT activity, while stimulation by the major fraction required incubation with 5 microM Cu2+, suggesting that the minor fraction was relatively labile to oxidation. The minor but definite presence of a plasma LDL subfraction more negative and susceptible to oxidation implicates the possibility of its association with atherogenesis.

Nonenzymatic Role for WRN in Preserving Nascent DNA Strands after Replication Stress

DOE PAGES

Su, Fengtao; Mukherjee, Shibani; Yang, Yanyong; ...

2014-11-20

WRN, the protein defective in Werner syndrome (WS), is a multifunctional nuclease involved in DNA damage repair, replication, and genome stability maintenance. It was assumed that the nuclease activities of WRN were critical for these functions. Here, we report a nonenzymatic role for WRN in preserving nascent DNA strands following replication stress. We found that lack of WRN led to shortening of nascent DNA strands after replication stress. Furthermore, we discovered that the exonuclease activity of MRE11 was responsible for the shortening of newly replicated DNA in the absence of WRN. Mechanistically, the N-terminal FHA domain of NBS1 recruits WRNmore » to replication-associated DNA double-stranded breaks to stabilize Rad51 and to limit the nuclease activity of its C-terminal binding partner MRE11. Thus, this previously unrecognized nonenzymatic function of WRN in the stabilization of nascent DNA strands sheds light on the molecular reason for the origin of genome instability in WS individuals.« less

A Randomized Study Comparing the Effects of a Low-Carbohydrate Diet and a Conventional Diet on Lipoprotein Subfractions and C-reactive Protein Levels in Patients With Severe Obesity.

PubMed

Moretti, Laura; Canada, Todd

2006-04-01

To compare the effects of a low-carbohydrate diet and a conventional (fat- and calorie-restricted) diet on lipoprotein subfractions and inflammation in severely obese subjects. We compared changes in lipoprotein subfractions and C-reactive protein levels in 78 severely obese subjects, including 86% with either diabetes or metabolic syndrome, who were randomly assigned to either a low-carbohydrate or conventional diet for 6 months. Subjects on a low-carbohydrate diet experienced a greater decrease in large very low-density lipoprotein (VLDL) levels (difference =-0.26 mg/dL, p = .03) but more frequently developed detectable chylomicrons (44% vs 22%, p = .04). Both diet groups experienced similar decreases in the number of low-density lipoprotein (LDL) particles (difference = -30 nmol/L, p = .74) and increases in large high-density lipoprotein (HDL) concentrations (difference = 0.70 mg/dL, p = .63). Overall, C-reactive protein levels decreased modestly in both diet groups. However, patients with a high-risk baseline level (>3 mg/dL, n = 48) experienced a greater decrease in C-reactive protein levels on a low-carbohydrate diet (adjusted difference = -2 mg/dL, p = .005), independent of weight loss. In this 6-month study involving severely obese subjects, we found an overall favorable effect of a low-carbohydrate diet on lipoprotein subfractions and on inflammation in high-risk subjects. Both diets had similar effects on LDL and HDL subfractions. ( Am J Med. 2004;117:398-405.).

A randomized study comparing the effects of a low-carbohydrate diet and a conventional diet on lipoprotein subfractions and C-reactive protein levels in patients with severe obesity.

PubMed

Seshadri, Prakash; Iqbal, Nayyar; Stern, Linda; Williams, Monica; Chicano, Kathryn L; Daily, Denise A; McGrory, Joyce; Gracely, Edward J; Rader, Daniel J; Samaha, Frederick F

2004-09-15

To compare the effects of a low-carbohydrate diet and a conventional (fat- and calorie-restricted) diet on lipoprotein subfractions and inflammation in severely obese subjects. We compared changes in lipoprotein subfractions and C-reactive protein levels in 78 severely obese subjects, including 86% with either diabetes or metabolic syndrome, who were randomly assigned to either a low-carbohydrate or conventional diet for 6 months. Subjects on a low-carbohydrate diet experienced a greater decrease in large very low-density lipoprotein (VLDL) levels (difference = -0.26 mg/dL, P = 0.03) but more frequently developed detectable chylomicrons (44% vs. 22%, P = 0.04). Both diet groups experienced similar decreases in the number of low-density lipoprotein (LDL) particles (difference = -30 nmol/L, P = 0.74) and increases in large high-density lipoprotein (HDL) concentrations (difference = 0.70 mg/dL, P = 0.63). Overall, C-reactive protein levels decreased modestly in both diet groups. However, patients with a high-risk baseline level (>3 mg/dL, n = 48) experienced a greater decrease in C-reactive protein levels on a low-carbohydrate diet (adjusted difference = -2.0 mg/dL, P = 0.005), independent of weight loss. In this 6-month study involving severely obese subjects, we found an overall favorable effect of a low-carbohydrate diet on lipoprotein subfractions, and on inflammation in high-risk subjects. Both diets had similar effects on LDL and HDL subfractions. Copyright 2004 Elsevier Inc.

Cloning of nascent monkey DNA synthesized early in the cell cycle.

PubMed

Kaufmann, G; Zannis-Hadjopoulos, M; Martin, R G

1985-04-01

To study the structure and complexity of animal cell replication origins, we have isolated and cloned nascent DNA from the onset of S phase as follows: African green monkey kidney cells arrested in G1 phase were serum stimulated in the presence of the DNA replication inhibitor aphidicolin. After 18 h, the drug was removed, and DNA synthesis was allowed to proceed in vivo for 1 min. Nuclei were then prepared, and DNA synthesis was briefly continued in the presence of Hg-dCTP. The mercury-labeled nascent DNA was purified in double-stranded form by extrusion (M. Zannis-Hadjopoulos, M. Perisco, and R. G. Martin, Cell 27:155-163, 1981) followed by sulfhydryl-agarose affinity chromatography. Purified nascent DNA (ca. 500 to 2,000 base pairs) was treated with mung bean nuclease to remove single-stranded ends and inserted into the NruI site of plasmid pBR322. The cloned fragments were examined for their time of replication by hybridization to cellular DNA fractions synthesized at various intervals of the S phase. Among five clones examined, four hybridized preferentially with early replicating fractions.

Elastic Coupling of Nascent apCAM Adhesions to Flowing Actin Networks

PubMed Central

Mejean, Cecile O.; Schaefer, Andrew W.; Buck, Kenneth B.; Kress, Holger; Shundrovsky, Alla; Merrill, Jason W.; Dufresne, Eric R.; Forscher, Paul

2013-01-01

Adhesions are multi-molecular complexes that transmit forces generated by a cell’s acto-myosin networks to external substrates. While the physical properties of some of the individual components of adhesions have been carefully characterized, the mechanics of the coupling between the cytoskeleton and the adhesion site as a whole are just beginning to be revealed. We characterized the mechanics of nascent adhesions mediated by the immunoglobulin-family cell adhesion molecule apCAM, which is known to interact with actin filaments. Using simultaneous visualization of actin flow and quantification of forces transmitted to apCAM-coated beads restrained with an optical trap, we found that adhesions are dynamic structures capable of transmitting a wide range of forces. For forces in the picoNewton scale, the nascent adhesions’ mechanical properties are dominated by an elastic structure which can be reversibly deformed by up to 1 µm. Large reversible deformations rule out an interface between substrate and cytoskeleton that is dominated by a number of stiff molecular springs in parallel, and favor a compliant cross-linked network. Such a compliant structure may increase the lifetime of a nascent adhesion, facilitating signaling and reinforcement. PMID:24039928

Nascent body ego: metapsychological and neurophysiological aspects.

PubMed

Lehtonen, Johannes; Partanen, Juhani; Purhonen, Maija; Valkonen-Korhonen, Minna; Kononen, Mervi; Saarikoski, Seppo; Launiala, Kari

2006-10-01

For Freud, body ego was the organizing basis of the structural theory. He defined it as a psychic projection of the body surface. Isakower's and Lewin's classical findings suggest that the body surface experiences of nursing provide the infant with sensory-affective stimulation that initiates a projection of sensory processes towards the psychic realm. During nursing, somato-sensory, gustatory and olfactory modalities merge with a primitive somatic affect of satiation, whereas auditory modality is involved more indirectly and visual contact more gradually. Repeated regularly, such nascent experiences are likely to play a part in the organization of the primitive protosymbolic mental experience. In support of this hypothesis, the authors review findings from a neurophysiological study of infants before, during and after nursing. Nursing is associated with a significant amplitude change in the newborn electroencephalogram (EEG), which wanes before the age of 3 months, and is transformed at the age of 6 months into rhythmic 3-5 Hz hedonic theta-activity. Sucking requires active physiological work, which is shown in a regular rise in heart rate. The hypothesis of a sensory-affective organization of the nascent body ego, enhanced by nursing and active sucking, seems concordant with neurophysiological phenomena related to nursing.

Structure of nascent replicative form DNA of coliphage M13

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dasgupta, S.; Mitra, S.

Nascent replicative form type II (RFII) DNA of coliphage M13 synthesized in an Escherichia coli mutant deficient in the 5' ..-->.. 3' exonuclease associated with DNA polymerase I contains ribonucleotides that are retained in the covalently closed RFI DNA sealed in vitro by the joint action of T5 phage DNA polymerase and T4 phage DNA ligase. These RFI molecules are labile to alkali and RNase H, unlike the RFI produced either in vivo or from RFII with E. coli DNA polymerase I and E. coli DNA ligase. The ribonucleotides are located at one site and predominantly in one strand ofmore » the nascent RF DNA. Furthermore, these molecules contain multiple small gaps, randomly located, and one large gap in the intracistronic region.« less

Protein Molecular Structures, Protein SubFractions, and Protein Availability Affected by Heat Processing: A Review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu,P.

2007-01-01

The utilization and availability of protein depended on the types of protein and their specific susceptibility to enzymatic hydrolysis (inhibitory activities) in the gastrointestine and was highly associated with protein molecular structures. Studying internal protein structure and protein subfraction profiles leaded to an understanding of the components that make up a whole protein. An understanding of the molecular structure of the whole protein was often vital to understanding its digestive behavior and nutritive value in animals. In this review, recently obtained information on protein molecular structural effects of heat processing was reviewed, in relation to protein characteristics affecting digestive behaviormore » and nutrient utilization and availability. The emphasis of this review was on (1) using the newly advanced synchrotron technology (S-FTIR) as a novel approach to reveal protein molecular chemistry affected by heat processing within intact plant tissues; (2) revealing the effects of heat processing on the profile changes of protein subfractions associated with digestive behaviors and kinetics manipulated by heat processing; (3) prediction of the changes of protein availability and supply after heat processing, using the advanced DVE/OEB and NRC-2001 models, and (4) obtaining information on optimal processing conditions of protein as intestinal protein source to achieve target values for potential high net absorbable protein in the small intestine. The information described in this article may give better insight in the mechanisms involved and the intrinsic protein molecular structural changes occurring upon processing.« less

Concentration, composition and apolipoprotein B species of very low density lipoprotein subfractions from normolipidemic and hypertriglyceridemic humans.

PubMed

Bittolo Bon, G; Cazzolato, G; Zago, S; Avogaro, P

1985-01-01

Lipoproteins in the d less than 1.006 g/ml density range obtained form 13 healthy normolipidemic subjects and from 15 patients affected by primary endogenous hypertriglyceridemia after 14-h fasting were subfractionated by filtration in Biogel A-15 M columns. The mass values and chemical composition of very low density lipoprotein (VLDL) subfractions 1 and 2 thus obtained were studied. In each subfraction the behavior of apolipoprotein B (Apo B) was tested by sodium dodecyl-sulfate polyacrylamide gel electrophoresis. VLDL2 was higher and richer in cholesterol and proteins than VLDL1, while the percentage content of triglycerides was lower. In hypertriglyceridemic patients both VLDL1 and VLDL2 were higher than in normolipidemic subjects, the difference being particularly evident for VLDL1. In both VLDL1 and VLDL2 of nearly all the subjects studied the presence in electrophoretic gels of a large Apo B-100 band and of a minor Apo B-48 band with the appropriate mobility of lymph chylomicrons was detected. The Apo B-100/Apo B-48 ratio was about 6 in VLDL1 and 24 in VLDL2. A trend of a reduced Apo B-100/Apo B-48 ratio was observed in VLDL1 of hypertriglyceridemic patients.

CAT-tailing as a fail-safe mechanism for efficient degradation of stalled nascent polypeptides

PubMed Central

Kostova, Kamena K.; Hickey, Kelsey L.; Osuna, Beatriz A.; Hussmann, Jeffrey A.; Frost, Adam; Weinberg, David E.; Weissman, Jonathan S.

2017-01-01

Ribosome stalling leads to recruitment of the Ribosome Quality control Complex (RQC), which targets the partially synthesized polypeptide for proteasomal degradation through the action of the ubiquitin ligase Ltn1p. A second core RQC component, Rqc2p, modifies the nascent polypeptide by adding a Carboxy-terminal Alanine and Threonine (CAT) tail through a non-canonical elongation reaction. Here we explore the role of CATtailing in nascent-chain degradation in budding yeast. We show that Ltn1p can efficiently access only nascent chain lysines immediately proximal to the ribosome exit tunnel. For substrates without Ltn1p-accessible lysines, CAT-tailing enables degradation by exposing lysines sequestered in the ribosome exit tunnel. Thus, CAT-tails do not serve as a degron, but rather provide a fail-safe mechanism that expands the range of RQC-degradable substrates. PMID:28751611

Three-dimensional organization of nascent rod outer segment disk membranes.

PubMed

Volland, Stefanie; Hughes, Louise C; Kong, Christina; Burgess, Barry L; Linberg, Kenneth A; Luna, Gabriel; Zhou, Z Hong; Fisher, Steven K; Williams, David S

2015-12-01

The vertebrate photoreceptor cell contains an elaborate cilium that includes a stack of phototransductive membrane disks. The disk membranes are continually renewed, but how new disks are formed remains poorly understood. Here we used electron microscope tomography to obtain 3D visualization of the nascent disks of rod photoreceptors in three mammalian species, to gain insight into the process of disk morphogenesis. We observed that nascent disks are invariably continuous with the ciliary plasma membrane, although, owing to partial enclosure, they can appear to be internal in 2D profiles. Tomographic analyses of the basal-most region of the outer segment show changes in shape of the ciliary plasma membrane indicating an invagination, which is likely a first step in disk formation. The invagination flattens to create the proximal surface of an evaginating lamella, as well as membrane protrusions that extend between adjacent lamellae, thereby initiating a disk rim. Immediately distal to this initiation site, lamellae of increasing diameter are evident, indicating growth outward from the cilium. In agreement with a previous model, our data indicate that mature disks are formed once lamellae reach full diameter, and the growth of a rim encloses the space between adjacent surfaces of two lamellae. This study provides 3D data of nascent and mature rod photoreceptor disk membranes at unprecedented z-axis depth and resolution, and provides a basis for addressing fundamental questions, ranging from protein sorting in the photoreceptor cilium to photoreceptor electrophysiology.

Prefoldin–Nascent Chain Complexes in the Folding of Cytoskeletal Proteins

PubMed Central

Hansen, William J.; Cowan, Nicholas J.; Welch, William J.

1999-01-01

In vitro transcription/translation of actin cDNA and analysis of the translation products by native-PAGE was used to study the maturation pathway of actin. During the course of actin synthesis, several distinct actin-containing species were observed and the composition of each determined by immunological procedures. After synthesis of the first ∼145 amino acids, the nascent ribosome-associated actin chain binds to the recently identified heteromeric chaperone protein, prefoldin (PFD). PFD remains bound to the relatively unfolded actin polypeptide until its posttranslational delivery to cytosolic chaperonin (CCT). We show that α- and β-tubulin follow a similar maturation pathway, but to date find no evidence for an interaction between PFD and several noncytoskeletal proteins. We conclude that PFD functions by selectively targeting nascent actin and tubulin chains pending their transfer to CCT for final folding and/or assembly. PMID:10209023

Long-read sequencing of nascent RNA reveals coupling among RNA processing events.

PubMed

Herzel, Lydia; Straube, Korinna; Neugebauer, Karla M

2018-06-14

Pre-mRNA splicing is accomplished by the spliceosome, a megadalton complex that assembles de novo on each intron. Because spliceosome assembly and catalysis occur cotranscriptionally, we hypothesized that introns are removed in the order of their transcription in genomes dominated by constitutive splicing. Remarkably little is known about splicing order and the regulatory potential of nascent transcript remodeling by splicing, due to the limitations of existing methods that focus on analysis of mature splicing products (mRNAs) rather than substrates and intermediates. Here, we overcome this obstacle through long-read RNA sequencing of nascent, multi-intron transcripts in the fission yeast Schizosaccharomyces pombe Most multi-intron transcripts were fully spliced, consistent with rapid cotranscriptional splicing. However, an unexpectedly high proportion of transcripts were either fully spliced or fully unspliced, suggesting that splicing of any given intron is dependent on the splicing status of other introns in the transcript. Supporting this, mild inhibition of splicing by a temperature-sensitive mutation in prp2 , the homolog of vertebrate U2AF65, increased the frequency of fully unspliced transcripts. Importantly, fully unspliced transcripts displayed transcriptional read-through at the polyA site and were degraded cotranscriptionally by the nuclear exosome. Finally, we show that cellular mRNA levels were reduced in genes with a high number of unspliced nascent transcripts during caffeine treatment, showing regulatory significance of cotranscriptional splicing. Therefore, overall splicing of individual nascent transcripts, 3' end formation, and mRNA half-life depend on the splicing status of neighboring introns, suggesting crosstalk among spliceosomes and the polyA cleavage machinery during transcription elongation. © 2018 Herzel et al.; Published by Cold Spring Harbor Laboratory Press.

Early-stage atherosclerosis in poloxamer 407-induced hyperlipidemic mice: pathological features and changes in the lipid composition of serum lipoprotein fractions and subfractions.

PubMed

Korolenko, Tatyana A; Johnston, Thomas P; Tuzikov, Fedor V; Tuzikova, Natalia A; Pupyshev, Alexandr B; Spiridonov, Victor K; Goncharova, Natalya V; Maiborodin, Igor V; Zhukova, Natalia A

2016-01-22

The aims of this study were to evaluate the effect of poloxamer 407 administration on atherogenic serum lipoprotein fractions and subfractions associated with cholesterol, triglycerides and phospholipids, as well as the onset of early atherosclerosis, in mice. Mice were administered either sterile saline or poloxamer 407 (to induce a dose-controlled hyperlipidemia) for 1 month and then sacrificed at 1, 4 and 10 days after the last dose of poloxamer 407. Systolic and diastolic blood pressure, the activity of a cysteine protease (cathepsin B) in cardiac and liver tissue, and histological/morphological examination of heart and liver specimens was performed for each group of mice at each time point. Lastly, small angle X-ray scattering was utilized to analyze the lipoprotein fractions and subfractions associated with cholesterol, triglycerides and phospholipids for both groups of mice at each time point. Statistical analysis was performed using one-way, analysis-of-variance with post hoc analysis to determine significantly different mean values, while correlation analysis employed the Spearman test. Poloxamer 407-treated mice revealed significant hyperlipidemia, moderately elevated blood pressure, general lipidosis in liver cells, increased cysteine protease activity in heart tissue, and contractile-type changes in cardiomyocytes. Similar to humans, the onset of atherosclerosis in poloxamer 407-treated mice was characterized by a steady increase in serum low-density, intermediate-density and very-low-density lipoprotein fractions, as well as very-low-density lipoprotein subfractions. We would propose that the sustained elevation of serum atherogenic lipoprotein fractions and subfractions induced by the administration of poloxamer 407 to mice resulted in the morphological changes we observed in both heart and liver cells, which are suggested to precede atherosclerosis, since this is a well-established mouse model of atherosclerosis. Since most of the cellular

High-density lipoprotein cholesterol subfractions HDL2 and HDL3 are reduced in women with rheumatoid arthritis and may augment the cardiovascular risk of women with RA: a cross-sectional study.

PubMed

Arts, Elke; Fransen, Jaap; Lemmers, Heidi; Stalenhoef, Anton; Joosten, Leo; van Riel, Piet; Popa, Calin D

2012-05-14

Higher levels of high density lipoprotein (HDL) subfractions HDL3-chol and particularly HDL2-chol protect against cardiovascular disease (CVD), but inflammation reduces the HDL level and may impair its anti-atherogenic effect. Changed HDL composition through the impact of inflammation on HDL subfractions may contribute to the excess risk of CVD in rheumatoid arthritis (RA). In this study, we investigated whether HDL2-chol and HDL3-chol concentrations differ between RA patients and healthy controls, and whether these levels are related to the level of RA disease activity. Non-fasting blood samples were collected from 45 RA patients and 45 healthy controls. None of the participants had a history of CVD, diabetes, or used lipid-lowering drugs. HDL2-chol and HDL3-chol concentrations were obtained by ultracentrifugation. Regression modeling was used to compare HDL subfraction levels between RA patients and healthy controls, and to analyze the effect of disease activity on HDL2-chol and HDL3-chol. HDL2-chol and HDL3-chol were significantly lower in RA patients compared to healthy controls (P = 0.01, P = 0.005, respectively). The HDL2:HDL3 ratio was significantly lower in patients compared to controls (P = 0.04). Reduced HDL2-chol and HDL3-chol levels were primarily present in female RA patients and not in male RA patients. A modest effect of the disease activity score in 28 joins ( DAS28) on HDL2-chol concentrations was found, after correction for disease duration, glucocorticosteroid use and body mass index (BMI), with a 0.06 mmol/L decrease with every point increase in DAS28 (P = 0.05). DAS28 did not significantly affect HDL3-chol concentrations (P = 0.186). Both HDL subfractions but particularly HDL2-chol concentrations were decreased in RA, primarily in women. This seems to be associated with disease activity and is of clinical relevance. The reduction of the HDL subfraction concentrations, particularly the supposedly beneficial HDL2-chol, may negatively impact the

CAT-tailing as a fail-safe mechanism for efficient degradation of stalled nascent polypeptides.

PubMed

Kostova, Kamena K; Hickey, Kelsey L; Osuna, Beatriz A; Hussmann, Jeffrey A; Frost, Adam; Weinberg, David E; Weissman, Jonathan S

2017-07-28

Ribosome stalling leads to recruitment of the ribosome quality control complex (RQC), which targets the partially synthesized polypeptide for proteasomal degradation through the action of the ubiquitin ligase Ltn1p. A second core RQC component, Rqc2p, modifies the nascent polypeptide by adding a carboxyl-terminal alanine and threonine (CAT) tail through a noncanonical elongation reaction. Here we examined the role of CAT-tailing in nascent-chain degradation in budding yeast. We found that Ltn1p efficiently accessed only nascent-chain lysines immediately proximal to the ribosome exit tunnel. For substrates without Ltn1p-accessible lysines, CAT-tailing enabled degradation by exposing lysines sequestered in the ribosome exit tunnel. Thus, CAT-tails do not serve as a degron, but rather provide a fail-safe mechanism that expands the range of RQC-degradable substrates. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Inhibition of lipid peroxidation by extracts/subfractions of Chickrassy ( Chukrasia tabularis A. Juss.)

NASA Astrophysics Data System (ADS)

Kaur, Rajbir; Thind, Tarunpreet Singh; Singh, Bikram; Arora, Saroj

2009-01-01

Polyphenols and polyphenol-rich fractions of plants have been reported to have protective effects against lipid peroxidation, most probably by serving as scavengers of free radicals and/or by chelating metal ions. In the present study, the effect of different extracts/subfractions of Chickrassy ( Chukrasia tabularis) on peroxyl radical mediated damage to the polyunsaturated fatty acids was investigated. Liver homogenate was used as experimental material. The production of malondialdehyde served as a marker of lipid peroxidation and oxidative stress. It was observed that polyphenol-rich fractions, particularly the ethyl acetate fractions of bark and leaves, showed the highest protective activity of 83.02% and 88.62% inhibition, respectively. This study will help in knowing the scientific validation of this plant, for its use in ayurvedic formulations.

A strategy for co-translational folding studies of ribosome-bound nascent chain complexes using NMR spectroscopy.

PubMed

Cassaignau, Anaïs M E; Launay, Hélène M M; Karyadi, Maria-Evangelia; Wang, Xiaolin; Waudby, Christopher A; Deckert, Annika; Robertson, Amy L; Christodoulou, John; Cabrita, Lisa D

2016-08-01

During biosynthesis on the ribosome, an elongating nascent polypeptide chain can begin to fold, in a process that is central to all living systems. Detailed structural studies of co-translational protein folding are now beginning to emerge; such studies were previously limited, at least in part, by the inherently dynamic nature of emerging nascent chains, which precluded most structural techniques. NMR spectroscopy is able to provide atomic-resolution information for ribosome-nascent chain complexes (RNCs), but it requires large quantities (≥10 mg) of homogeneous, isotopically labeled RNCs. Further challenges include limited sample working concentration and stability of the RNC sample (which contribute to weak NMR signals) and resonance broadening caused by attachment to the large (2.4-MDa) ribosomal complex. Here, we present a strategy to generate isotopically labeled RNCs in Escherichia coli that are suitable for NMR studies. Uniform translational arrest of the nascent chains is achieved using a stalling motif, and isotopically labeled RNCs are produced at high yield using high-cell-density E. coli growth conditions. Homogeneous RNCs are isolated by combining metal affinity chromatography (to isolate ribosome-bound species) with sucrose density centrifugation (to recover intact 70S monosomes). Sensitivity-optimized NMR spectroscopy is then applied to the RNCs, combined with a suite of parallel NMR and biochemical analyses to cross-validate their integrity, including RNC-optimized NMR diffusion measurements to report on ribosome attachment in situ. Comparative NMR studies of RNCs with the analogous isolated proteins permit a high-resolution description of the structure and dynamics of a nascent chain during its progressive biosynthesis on the ribosome.

Bioorthogonal Metabolic Labeling of Nascent RNA in Neurons Improves the Sensitivity of Transcriptome-Wide Profiling.

PubMed

Zajaczkowski, Esmi L; Zhao, Qiong-Yi; Zhang, Zong Hong; Li, Xiang; Wei, Wei; Marshall, Paul R; Leighton, Laura J; Nainar, Sarah; Feng, Chao; Spitale, Robert C; Bredy, Timothy W

2018-06-15

Transcriptome-wide expression profiling of neurons has provided important insights into the underlying molecular mechanisms and gene expression patterns that transpire during learning and memory formation. However, there is a paucity of tools for profiling stimulus-induced RNA within specific neuronal cell populations. A bioorthogonal method to chemically label nascent (i.e., newly transcribed) RNA in a cell-type-specific and temporally controlled manner, which is also amenable to bioconjugation via click chemistry, was recently developed and optimized within conventional immortalized cell lines. However, its value within a more fragile and complicated cellular system such as neurons, as well as for transcriptome-wide expression profiling, has yet to be demonstrated. Here, we report the visualization and sequencing of activity-dependent nascent RNA derived from neurons using this labeling method. This work has important implications for improving transcriptome-wide expression profiling and visualization of nascent RNA in neurons, which has the potential to provide valuable insights into the mechanisms underlying neural plasticity, learning, and memory.

The recruitment of the U5 snRNP to nascent transcripts requires internal loop 1 of U5 snRNA.

PubMed

Kim, Rebecca; Paschedag, Joshua; Novikova, Natalya; Bellini, Michel

2012-12-01

In this study, we take advantage of the high spatial resolution offered by the nucleus and lampbrush chromosomes of the amphibian oocyte to investigate the mechanisms that regulate the intranuclear trafficking of the U5 snRNP and its recruitment to nascent transcripts. We monitor the fate of newly assembled fluorescent U5 snRNP in Xenopus oocytes depleted of U4 and/or U6 snRNAs and demonstrate that the U4/U6.U5 tri-snRNP is not required for the association of U5 snRNP with Cajal bodies, splicing speckles, and nascent transcripts. In addition, using a mutational analysis, we show that a non-functional U5 snRNP can associate with nascent transcripts, and we further characterize internal loop structure 1 of U5 snRNA as a critical element for licensing U5 snRNP to target both nascent transcripts and splicing speckles. Collectively, our data support the model where the recruitment of snRNPs onto pre-mRNAs is independent of spliceosome assembly and suggest that U5 snRNP may promote the association of the U4/U6.U5 tri-snRNP with nascent transcripts.

Mediterranean diet supplemented with nuts reduces waist circumference and shifts lipoprotein subfractions to a less atherogenic pattern in subjects at high cardiovascular risk.

PubMed

Damasceno, Nagila R T; Sala-Vila, Aleix; Cofán, Montserrat; Pérez-Heras, Ana M; Fitó, Montserrat; Ruiz-Gutiérrez, Valentina; Martínez-González, Miguel-Ángel; Corella, Dolores; Arós, Fernando; Estruch, Ramon; Ros, Emilio

2013-10-01

The PREDIMED trial showed that Mediterranean diets supplemented with either extra-virgin olive oil or nuts reduced incident cardiovascular events compared to a control diet. Consumption of both supplemental foods has been associated with reduced LDL-cholesterol, but it is unknown whether they can shift lipoprotein subfractions to a less atherogenic pattern. We investigated changes in adiposity and lipoprotein subfractions after consumption of the PREDIMED diets. In a PREDIMED sub-cohort (n = 169), lipoprotein subclasses (particle concentrations and size) were determined by nuclear magnetic resonance spectroscopy at baseline and after intervention for 1 year. Participants allocated to the Mediterranean diet supplemented with nuts showed significant reductions from baseline of waist circumference (mean [95% CI]; -5 cm [-7; -3]) and concentrations of medium-small (-27 nmol/l [-46; -8]) and very small LDL (-111 nmol/l [-180; -42]); decreased LDL particle number (a nuclear magnetic resonance-specific measurement) (-98 nmol/l [-184; -11]); and an increase of large LDL concentrations (54 nmol/l [18; 90]), with a net increase (0.2 nmol/l [0.1; 0.4]) of LDL size. The Mediterranean diets with olive oil and nuts increased large HDL concentrations (0.6 μM [0.0; 1.1] and 1.0 μM [0.4; 1.5], respectively). Compared to the other two intervention groups, participants in the nut-enriched diet showed significantly reduced waist circumference (p ≤ 0.006, both) and increased LDL size (p < 0.05, both). Lipoprotein subfractions are shifted to a less atherogenic pattern by consumption of Mediterranean diets enriched with nuts. The results contribute mechanistic evidence for the reduction of cardiovascular events observed in the PREDIMED trial. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

A Possible Role of the Full-Length Nascent Protein in Post-Translational Ribosome Recycling.

PubMed

Das, Debasis; Samanta, Dibyendu; Bhattacharya, Arpita; Basu, Arunima; Das, Anindita; Ghosh, Jaydip; Chakrabarti, Abhijit; Das Gupta, Chanchal

2017-01-01

Each cycle of translation initiation in bacterial cell requires free 50S and 30S ribosomal subunits originating from the post-translational dissociation of 70S ribosome from the previous cycle. Literature shows stable dissociation of 70S from model post-termination complexes by the concerted action of Ribosome Recycling Factor (RRF) and Elongation Factor G (EF-G) that interact with the rRNA bridge B2a/B2b joining 50S to 30S. In such experimental models, the role of full-length nascent protein was never considered seriously. We observed relatively slow release of full-length nascent protein from 50Sof post translation ribosome, and in that process, its toe prints on the rRNA in vivo and in in vitro translation with E.coli S30 extract. We reported earlier that a number of chemically unfolded proteins like bovine carbonic anhydrase (BCA), lactate dehydrogenase (LDH), malate dehydrogenase (MDH), lysozyme, ovalbumin etc., when added to free 70Sin lieu of the full length nascent proteins, also interact with identical RNA regions of the 23S rRNA. Interestingly the rRNA nucleotides that slow down release of the C-terminus of full-length unfolded protein were found in close proximity to the B2a/B2b bridge. It indicated a potentially important chemical reaction conserved throughout the evolution. Here we set out to probe that conserved role of unfolded protein conformation in splitting the free or post-termination 70S. How both the RRF-EFG dependent and the plausible nascent protein-EFG dependent ribosome recycling pathways might be relevant in bacteria is discussed here.

A Possible Role of the Full-Length Nascent Protein in Post-Translational Ribosome Recycling

PubMed Central

Das, Debasis; Samanta, Dibyendu; Bhattacharya, Arpita; Basu, Arunima; Das, Anindita; Ghosh, Jaydip; Chakrabarti, Abhijit; Das Gupta, Chanchal

2017-01-01

Each cycle of translation initiation in bacterial cell requires free 50S and 30S ribosomal subunits originating from the post-translational dissociation of 70S ribosome from the previous cycle. Literature shows stable dissociation of 70S from model post-termination complexes by the concerted action of Ribosome Recycling Factor (RRF) and Elongation Factor G (EF-G) that interact with the rRNA bridge B2a/B2b joining 50S to 30S. In such experimental models, the role of full-length nascent protein was never considered seriously. We observed relatively slow release of full-length nascent protein from 50Sof post translation ribosome, and in that process, its toe prints on the rRNA in vivo and in in vitro translation with E.coli S30 extract. We reported earlier that a number of chemically unfolded proteins like bovine carbonic anhydrase (BCA), lactate dehydrogenase (LDH), malate dehydrogenase (MDH), lysozyme, ovalbumin etc., when added to free 70Sin lieu of the full length nascent proteins, also interact with identical RNA regions of the 23S rRNA. Interestingly the rRNA nucleotides that slow down release of the C-terminus of full-length unfolded protein were found in close proximity to the B2a/B2b bridge. It indicated a potentially important chemical reaction conserved throughout the evolution. Here we set out to probe that conserved role of unfolded protein conformation in splitting the free or post-termination 70S. How both the RRF-EFG dependent and the plausible nascent protein–EFG dependent ribosome recycling pathways might be relevant in bacteria is discussed here. PMID:28099529

Role of the visual experience-dependent nascent proteome in neuronal plasticity

PubMed Central

Liu, Han-Hsuan; McClatchy, Daniel B; Schiapparelli, Lucio; Shen, Wanhua; Yates, John R

2018-01-01

Experience-dependent synaptic plasticity refines brain circuits during development. To identify novel protein synthesis-dependent mechanisms contributing to experience-dependent plasticity, we conducted a quantitative proteomic screen of the nascent proteome in response to visual experience in Xenopus optic tectum using bio-orthogonal metabolic labeling (BONCAT). We identified 83 differentially synthesized candidate plasticity proteins (CPPs). The CPPs form strongly interconnected networks and are annotated to a variety of biological functions, including RNA splicing, protein translation, and chromatin remodeling. Functional analysis of select CPPs revealed the requirement for eukaryotic initiation factor three subunit A (eIF3A), fused in sarcoma (FUS), and ribosomal protein s17 (RPS17) in experience-dependent structural plasticity in tectal neurons and behavioral plasticity in tadpoles. These results demonstrate that the nascent proteome is dynamic in response to visual experience and that de novo synthesis of machinery that regulates RNA splicing and protein translation is required for experience-dependent plasticity. PMID:29412139

Theory of Force Regulation by Nascent Adhesion Sites

PubMed Central

Bruinsma, Robijn

2005-01-01

The mechanical coupling of a cell with the extracellular matrix relies on adhesion sites, clusters of membrane-associated proteins that communicate forces generated along the F-Actin filaments of the cytoskeleton to connecting tissue. Nascent adhesion sites have been shown to regulate these forces in response to tissue rigidity. Force-regulation by substrate rigidity of adhesion sites with fixed area is not possible for stationary adhesion sites, according to elasticity theory. A simple model is presented to describe force regulation by dynamical adhesion sites. PMID:15849245

Heat-induced Protein Structure and Subfractions in Relation to Protein Degradation Kinetics and Intestinal Availability in Dairy Cattle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doiron, K.; Yu, P; McKinnon, J

2009-01-01

The objectives of this study were to reveal protein structures of feed tissues affected by heat processing at a cellular level, using the synchrotron-based Fourier transform infrared microspectroscopy as a novel approach, and quantify protein structure in relation to protein digestive kinetics and nutritive value in the rumen and intestine in dairy cattle. The parameters assessed included (1) protein structure a-helix to e-sheet ratio; (2) protein subfractions profiles; (3) protein degradation kinetics and effective degradability; (4) predicted nutrient supply using the intestinally absorbed protein supply (DVE)/degraded protein balance (OEB) system for dairy cattle. In this study, Vimy flaxseed protein wasmore » used as a model feed protein and was autoclave-heated at 120C for 20, 40, and 60 min in treatments T1, T2, and T3, respectively. The results showed that using the synchrotron-based Fourier transform infrared microspectroscopy revealed and identified the heat-induced protein structure changes. Heating at 120C for 40 and 60 min increased the protein structure a-helix to e-sheet ratio. There were linear effects of heating time on the ratio. The heating also changed chemical profiles, which showed soluble CP decreased upon heating with concomitant increases in nonprotein nitrogen, neutral, and acid detergent insoluble nitrogen. The protein subfractions with the greatest changes were PB1, which showed a dramatic reduction, and PB2, which showed a dramatic increase, demonstrating a decrease in overall protein degradability. In situ results showed a reduction in rumen-degradable protein and in rumen-degradable dry matter without differences between the treatments. Intestinal digestibility, determined using a 3-step in vitro procedure, showed no changes to rumen undegradable protein. Modeling results showed that heating increased total intestinally absorbable protein (feed DVE value) and decreased degraded protein balance (feed OEB value), but there were no

Rqc2p and 60S ribosomal subunits mediate mRNA-independent elongation of nascent chains

PubMed Central

Shen, Peter S.; Park, Joseph; Qin, Yidan; Li, Xueming; Parsawar, Krishna; Larson, Matthew H.; Cox, James; Cheng, Yifan; Lambowitz, Alan M.; Weissman, Jonathan S.; Brandman, Onn; Frost, Adam

2015-01-01

In Eukarya, stalled translation induces 40S dissociation and recruitment of the Ribosome Quality control Complex (RQC) to the 60S subunit, which mediates nascent chain degradation. Here, we report cryoEM structures revealing that the RQC components Rqc2p (YPL009C/Tae2) and Ltn1p (YMR247C/Rkr1) bind to the 60S at sites exposed after 40S dissociation, placing the Ltn1p RING domain near the exit channel and Rqc2p over the P-site tRNA. We further demonstrate that Rqc2p recruits alanine and threonine charged tRNA to the A-site and directs elongation of nascent chains independently of mRNA or 40S subunits. Our work uncovers an unexpected mechanism of protein synthesis in which a protein—not an mRNA—determines tRNA recruitment and the tagging of nascent chains with Carboxy-terminal Ala and Thr extensions (“CAT tails”). PMID:25554787

Association of protein structure, protein and carbohydrate subfractions with bioenergy profiles and biodegradation functions in modeled forage

NASA Astrophysics Data System (ADS)

Ji, Cuiying; Zhang, Xuewei; Yu, Peiqiang

2016-03-01

The objectives of this study were to detect unique aspects and association of forage protein inherent structure, biological compounds, protein and carbohydrate subfractions, bioenergy profiles, and biodegradation features. In this study, common available alfalfa hay from two different sourced-origins (FSO vs. CSO) was used as a modeled forage for inherent structure profile, bioenergy, biodegradation and their association between their structure and bio-functions. The molecular spectral profiles were determined using non-invasive molecular spectroscopy. The parameters included: protein structure amide I group, amide II group and their ratios; protein subfractions (PA1, PA2, PB1, PB2, PC); carbohydrate fractions (CA1, CA2, CA3, CA4, CB1, CB2, CC); biodegradable and undegradable fractions of protein (RDPA2, RDPB1, RDPB2, RDP; RUPA2 RUPB1, RUPB2, RUPC, RUP); biodegradable and undegradable fractions of carbohydrate (RDCA4, RDCB1, RDCB2, RDCB3, RDCHO; RUCA4, RUCB1; RUCB2; RUCB3 RUCC, RUCHO) and bioenergy profiles (tdNDF, tdFA, tdCP, tdNFC, TDN1 ×, DE3 ×, ME3 ×, NEL3 ×; NEm, NEg). The results show differences in protein and carbohydrate (CHO) subfractions in the moderately degradable true protein fraction (PB1: 502 vs. 420 g/kg CP, P = 0.09), slowly degraded true protein fraction (PB2: 45 vs. 96 g/kg CP, P = 0.02), moderately degradable CHO fraction (CB2: 283 vs. 223 g/kg CHO, P = 0.06) and slowly degraded CHO fraction (CB3: 369 vs. 408 g/kg CHO) between the two sourced origins. As to biodegradable (RD) fractions of protein and CHO in rumen, there were differences in RD of PB1 (417 vs. 349 g/kg CP, P = 0.09), RD of PB2 (29 vs. 62 g/kg CP, P = 0.02), RD of CB2 (251 vs. 198 g/kg DM, P = 0.06), RD of CB3 (236 vs. 261 g/kg CHO, P = 0.08). As to bioenergy profile, there were differences in total digestible nutrient (TDN: 551 vs. 537 g/kg DM, P = 0.06), and metabolic bioenergy (P = 0.095). As to protein molecular structure, there were differences in protein structure 1st

An Annotation Agnostic Algorithm for Detecting Nascent RNA Transcripts in GRO-Seq.

PubMed

Azofeifa, Joseph G; Allen, Mary A; Lladser, Manuel E; Dowell, Robin D

2017-01-01

We present a fast and simple algorithm to detect nascent RNA transcription in global nuclear run-on sequencing (GRO-seq). GRO-seq is a relatively new protocol that captures nascent transcripts from actively engaged polymerase, providing a direct read-out on bona fide transcription. Most traditional assays, such as RNA-seq, measure steady state RNA levels which are affected by transcription, post-transcriptional processing, and RNA stability. GRO-seq data, however, presents unique analysis challenges that are only beginning to be addressed. Here, we describe a new algorithm, Fast Read Stitcher (FStitch), that takes advantage of two popular machine-learning techniques, hidden Markov models and logistic regression, to classify which regions of the genome are transcribed. Given a small user-defined training set, our algorithm is accurate, robust to varying read depth, annotation agnostic, and fast. Analysis of GRO-seq data without a priori need for annotation uncovers surprising new insights into several aspects of the transcription process.

Interplay of signal recognition particle and trigger factor at L23 near the nascent chain exit site on the Escherichia coli ribosome

PubMed Central

Ullers, Ronald S.; Houben, Edith N.G.; Raine, Amanda; ten Hagen-Jongman, Corinne M.; Ehrenberg, Måns; Brunner, Joseph; Oudega, Bauke; Harms, Nellie; Luirink, Joen

2003-01-01

As newly synthesized polypeptides emerge from the ribosome, they interact with chaperones and targeting factors that assist in folding and targeting to the proper location in the cell. In Escherichia coli, the chaperone trigger factor (TF) binds to nascent polypeptides early in biosynthesis facilitated by its affinity for the ribosomal proteins L23 and L29 that are situated around the nascent chain exit site on the ribosome. The targeting factor signal recognition particle (SRP) interacts specifically with the signal anchor (SA) sequence in nascent inner membrane proteins (IMPs). Here, we have used photocross-linking to map interactions of the SA sequence in a short, in vitro–synthesized, nascent IMP. Both TF and SRP were found to interact with the SA with partially overlapping binding specificity. In addition, extensive contacts with L23 and L29 were detected. Both purified TF and SRP could be cross-linked to L23 on nontranslating ribosomes with a competitive advantage for SRP. The results suggest a role for L23 in the targeting of IMPs as an attachment site for TF and SRP that is close to the emerging nascent chain. PMID:12756233

Subfractions of high-density lipoprotein (HDL) and dysfunctional HDL in chronic kidney disease patients.

PubMed

Rysz-Górzyńska, Magdalena; Banach, Maciej

2016-08-01

A number of studies have shown that chronic kidney disease (CKD) is associated with increased risk for cardiovascular disease (CVD). Chronic kidney disease is characterized by significant disturbances in lipoprotein metabolism, including differences in quantitative and qualitative content of high-density lipoprotein (HDL) particles. Recent studies have revealed that serum HDL cholesterol levels do not predict CVD in CKD patients; thus CKD-induced modifications in high-density lipoprotein (HDL) may be responsible for the increase in CV risk in CKD patients. Various methods are available to separate several subclasses of HDL and confirm their atheroprotective properties. However, under pathological conditions associated with inflammation and oxidation, HDL can progressively lose normal biological activities and be converted into dysfunctional HDL. In this review, we highlight the current state of knowledge on subfractions of HDL and HDL dysfunction in CKD.

Atherogenic Lipoprotein Subfractions Determined by Ion Mobility and First Cardiovascular Events After Random Allocation to High-Intensity Statin or Placebo: The Justification for the Use of Statins in Prevention: An Intervention Trial Evaluating Rosuvastatin (JUPITER) Trial.

PubMed

Mora, Samia; Caulfield, Michael P; Wohlgemuth, Jay; Chen, Zhihong; Superko, H Robert; Rowland, Charles M; Glynn, Robert J; Ridker, Paul M; Krauss, Ronald M

2015-12-08

Cardiovascular disease (CVD) can occur in individuals with low low-density lipoprotein (LDL) cholesterol (LDL-C). We investigated whether detailed measures of LDL subfractions and other lipoproteins can be used to assess CVD risk in a population with both low LDL-C and high C-reactive protein who were randomized to high-intensity statin or placebo. In 11 186 Justification for the Use of Statins in Prevention: An Intervention Trial Evaluating Rosuvastatin (JUPITER) participants, we tested whether lipids, apolipoproteins, and ion mobility-measured particle concentrations at baseline and after random allocation to rosuvastatin 20 mg/d or placebo were associated with first CVD events (n=307) or CVD/all-cause death (n=522). In placebo-allocated participants, baseline LDL-C was not associated with CVD (adjusted hazard ratio [HR] per SD, 1.03; 95% confidence interval [CI], 0.88-1.21). In contrast, associations with CVD events were observed for baseline non-high-density lipoprotein (HDL) cholesterol (HR, 1.18; 95% CI, 1.01-1.38), apolipoprotein B (HR, 1.28; 95% CI, 1.11-1.48), and ion mobility-measured non-HDL particles (HR, 1.19; 95% CI, 1.05-1.35) and LDL particles (HR, 1.21; 95% CI, 1.07-1.37). Association with CVD events was also observed for several LDL and very-low-density lipoprotein subfractions but not for ion mobility-measured HDL subfractions. In statin-allocated participants, CVD events were associated with on-treatment LDL-C, non-HDL cholesterol, and apolipoprotein B; these were also associated with CVD/all-cause death, as were several LDL and very-low-density lipoprotein subfractions, albeit with a pattern of association that differed from the baseline risk. In JUPITER, baseline LDL-C was not associated with CVD events, in contrast with significant associations for non-HDL cholesterol and atherogenic particles: apolipoprotein B and ion mobility-measured non-HDL particles, LDL particles, and select subfractions of very-low-density lipoprotein particles and

Mechanisms of nascent fiber formation during avian skeletal muscle hypertrophy

NASA Technical Reports Server (NTRS)

McCormick, K. M.; Schultz, E.

1992-01-01

This study examined two putative mechanisms of new fiber formation in postnatal skeletal muscle, namely longitudinal fragmentation of existing fibers and de novo formation. The relative contributions of these two mechanisms to fiber formation in hypertrophying anterior latissimus dorsi (ALD) muscle were assessed by quantitative analysis of their nuclear populations. Muscle hypertrophy was induced by wing-weighting for 1 week. All nuclei formed during the weighting period were labeled by continuous infusion of 5-bromo-2'-deoxyuridine (BrdU), a thymidine analog, and embryonic-like fibers were identified using an antibody to ventricular-like embryonic (V-EMB) myosin. The number of BrdU-labeled and unlabeled nuclei in V-EMB-positive fibers were counted. Wing-weighting resulted in significant muscle enlargement and the appearance of many V-EMB+ fibers. The majority of V-EMB+ fibers were completely independent of mature fibers and had a nuclear density characteristics of developing fibers. Furthermore, nearly 100% of the nuclei in independent V-EMB+ fibers were labeled. These findings strongly suggest that most V-EMB+ fibers were nascent fibers formed de novo during the weighting period by satellite cell activation and fusion. Nascent fibers were found primarily in the space between fascicles where they formed a complex anastomosing network of fibers running at angles to one another. Although wing-weighting induced an increase in the number of branched fibers, there was no evidence that V-EMB+ fibers were formed by longitudinal fragmentation. The location of newly formed fibers in wing-weighted and regenerating ALD muscle was compared to determine whether satellite cells in the ALD muscle were unusual in that, if stimulated to divide, they would form fibers in the inter- and intrafascicular space. In contrast to wing-weighted muscle, nascent fibers were always found closely associated with necrotic fibers. These results suggest that wing-weighting is not simply another

The Fate of Nascent APP in Hippocampal Neurons: A Live Cell Imaging Study.

PubMed

DelBove, Claire E; Deng, Xian-Zhen; Zhang, Qi

2018-06-21

Amyloid precursor protein (APP) is closely associated with Alzheimer's disease (AD) because its proteolytic products form amyloid plaques and its mutations are linked to familial AD patients. As a membrane protein, APP is involved in neuronal development and plasticity. However, it remains unclear how nascent APP is distributed and transported to designated membrane compartments to execute its diverse functions. Here, we employed a dual-tagged APP fusion protein in combination with a synaptic vesicle marker to study the surface trafficking and cleavage of APP in hippocampal neurons immediately after its synthesis. Using long-term time-lapse imaging, we found that a considerable amount of nascent APP was directly transported to the somatodendritic surface, from which it propagates to distal neurites. Some APP in the plasma membrane was endocytosed and some was cleaved by α-secretase. Hence, we conclude that surface transportation of APP is a major step preceding its proteolytic processing and neuritic distribution.

RNA polymerase pausing and nascent RNA structure formation are linked through clamp domain movement

PubMed Central

Hein, Pyae P.; Kolb, Kellie E.; Windgassen, Tricia; Bellecourt, Michael J.; Darst, Seth A.; Mooney, Rachel A.; Landick, Robert

2014-01-01

The rates of RNA synthesis and nascent RNA folding into biologically active structures are linked via pausing by RNA polymerase (RNAP). Structures that form within the RNA exit channel can increase pausing by interacting with bacterial RNAP or decrease pausing by preventing backtracking. Conversely, pausing is required for proper folding of some RNAs. Opening of the RNAP clamp domain is proposed to mediate some effects of nascent RNA structures. However, the connections among RNA structure formation, clamp movement, and catalytic activity remain uncertain. We assayed exit-channel structure formation in Escherichia coli RNAP together with disulfide crosslinks that favor closed or open clamp conformations and found that clamp position directly influences RNA structure formation and catalytic activity. We report that exit-channel RNA structures slow pause escape by favoring clamp opening and through interactions with the flap that slow translocation. PMID:25108353

Binding of Signal Recognition Particle Gives Ribosome/Nascent Chain Complexes a Competitive Advantage in Endoplasmic Reticulum Membrane Interaction

PubMed Central

Neuhof, Andrea; Rolls, Melissa M.; Jungnickel, Berit; Kalies, Kai-Uwe; Rapoport, Tom A.

1998-01-01

Most secretory and membrane proteins are sorted by signal sequences to the endoplasmic reticulum (ER) membrane early during their synthesis. Targeting of the ribosome-nascent chain complex (RNC) involves the binding of the signal sequence to the signal recognition particle (SRP), followed by an interaction of ribosome-bound SRP with the SRP receptor. However, ribosomes can also independently bind to the ER translocation channel formed by the Sec61p complex. To explain the specificity of membrane targeting, it has therefore been proposed that nascent polypeptide-associated complex functions as a cytosolic inhibitor of signal sequence- and SRP-independent ribosome binding to the ER membrane. We report here that SRP-independent binding of RNCs to the ER membrane can occur in the presence of all cytosolic factors, including nascent polypeptide-associated complex. Nontranslating ribosomes competitively inhibit SRP-independent membrane binding of RNCs but have no effect when SRP is bound to the RNCs. The protective effect of SRP against ribosome competition depends on a functional signal sequence in the nascent chain and is also observed with reconstituted proteoliposomes containing only the Sec61p complex and the SRP receptor. We conclude that cytosolic factors do not prevent the membrane binding of ribosomes. Instead, specific ribosome targeting to the Sec61p complex is provided by the binding of SRP to RNCs, followed by an interaction with the SRP receptor, which gives RNC–SRP complexes a selective advantage in membrane targeting over nontranslating ribosomes. PMID:9436994

Substantial Goodness and Nascent Human Life.

PubMed

Floyd, Shawn

2015-09-01

Many believe that moral value is--at least to some extent--dependent on the developmental states necessary for supporting rational activity. My paper rejects this view, but does not aim simply to register objections to it. Rather, my essay aims to answer the following question: if a human being's developmental state and occurrent capacities do not bequeath moral standing, what does? The question is intended to prompt careful consideration of what makes human beings objects of moral value, dignity, or (to employ my preferred term) goodness. Not only do I think we can answer this question, I think we can show that nascent human life possesses goodness of precisely this sort. I appeal to Aquinas's metaethics to establish the conclusion that the goodness of a human being--even if that being is an embryo or fetus--resides at the substratum of her existence. If she possesses goodness, it is because human existence is good.

Decreased APOE-containing HDL subfractions and cholesterol efflux capacity of serum in mice lacking Pcsk9

PubMed Central

2013-01-01

Background Studies in animals showed that PCSK9 is involved in HDL metabolism. We investigated the molecular mechanism by which PCSK9 regulates HDL cholesterol concentration and also whether Pcsk9 inactivation might affect cholesterol efflux capacity of serum and atherosclerotic fatty streak volume. Methods Mass spectrometry and western blot were used to analyze the level of apolipoprotein E (APOE) and A1 (APOA1). A mouse model overexpressing human LDLR was used to test the effect of high levels of liver LDLR on the concentration of HDL cholesterol and APOE-containing HDL subfractions. Pcsk9 knockout males lacking LDLR and APOE were used to test whether LDLR and APOE are necessary for PCSK9-mediated HDL cholesterol regulation. We also investigated the effects of Pcsk9 inactivation on cholesterol efflux capacity of serum using THP-1 and J774.A1 macrophage foam cells and atherosclerotic fatty streak volume in the aortic sinus of Pcsk9 knockout males fed an atherogenic diet. Results APOE and APOA1 were reduced in the same HDL subfractions of Pcsk9 knockout and human LDLR transgenic male mice. In Pcsk9/Ldlr double-knockout mice, HDL cholesterol concentration was lower than in Ldlr knockout mice and higher than in wild-type controls. In Pcsk9/Apoe double-knockout mice, HDL cholesterol concentration was similar to that of Apoe knockout males. In Pcsk9 knockout males, THP-1 macrophage cholesterol efflux capacity of serum was reduced and the fatty streak lesion volume was similar to wild-type controls. Conclusions In mice, LDLR and APOE are important factors for PCSK9-mediated HDL regulation. Our data suggest that, although LDLR plays a major role in PCSK9-mediated regulation of HDL cholesterol concentration, it is not the only mechanism and that, regardless of mechanism, APOE is essential. Pcsk9 inactivation decreases the HDL cholesterol concentration and cholesterol efflux capacity in serum, but does not increase atherosclerotic fatty streak volume. PMID:23883163

Reactive uptake of HOCl to laboratory generated sea salt particles and nascent sea-spray aerosol

NASA Astrophysics Data System (ADS)

Campbell, N. R.; Ryder, O. S.; Bertram, T. H.

2013-12-01

Field observations suggest that the reactive uptake of HOCl on marine aerosol particles is an important source of chlorine radicals, particularly under low NOx conditions. However to date, laboratory measurements disagree on the magnitude of the reactive uptake coefficient for HOCl by a factor of 5 (γ(HOCl) ranges between 0.0004 and 0.0018), and there are no measurements of γ(HOCl) on nascent sea-spray aerosol. Here, we present measurements of the reactive uptake of HOCl to laboratory generated sodium chloride and sea-spray aerosol particles generated in a novel Marine Aerosol Reference Tank (MART), coupled to an entrained aerosol flow reactor and Chemical Ionization Mass Spectrometer (CIMS). Measurements of γ(HOCl) retrieved here are compared against those in the literature, and the role of organic coatings on nascent sea-spray aerosol is explored.

Randomized Comparison of 3 High-Level Disinfection and Sterilization Procedures for Duodenoscopes.

PubMed

Snyder, Graham M; Wright, Sharon B; Smithey, Anne; Mizrahi, Meir; Sheppard, Michelle; Hirsch, Elizabeth B; Chuttani, Ram; Heroux, Riley; Yassa, David S; Olafsdottir, Lovisa B; Davis, Roger B; Anastasiou, Jiannis; Bapat, Vijay; Bidari, Kiran; Pleskow, Douglas K; Leffler, Daniel; Lane, Benjamin; Chen, Alice; Gold, Howard S; Bartley, Anthony; King, Aleah D; Sawhney, Mandeep S

2017-10-01

Duodenoscopes have been implicated in the transmission of multidrug-resistant organisms (MDRO). We compared the frequency of duodenoscope contamination with MDRO or any other bacteria after disinfection or sterilization by 3 different methods. We performed a single-center prospective randomized study in which duodenoscopes were randomly reprocessed by standard high-level disinfection (sHLD), double high-level disinfection (dHLD), or standard high-level disinfection followed by ethylene oxide gas sterilization (HLD/ETO). Samples were collected from the elevator mechanism and working channel of each duodenoscope and cultured before use. The primary outcome was the proportion of duodenoscopes with an elevator mechanism or working channel culture showing 1 or more MDRO; secondary outcomes included the frequency of duodenoscope contamination with more than 0 and 10 or more colony-forming units (CFU) of aerobic bacterial growth on either sampling location. After 3 months of enrollment, the study was closed because of the futility; we did not observe sufficient events to evaluate the primary outcome. Among 541 duodenoscope culture events, 516 were included in the final analysis. No duodenoscope culture in any group was positive for MDRO. Bacterial growth of more than 0 CFU was noted in 16.1% duodenoscopes in the sHLD group, 16.0% in the dHLD group, and 22.5% in the HLD/ETO group (P = .21). Bacterial growth or 10 or more CFU was noted in 2.3% of duodenoscopes in the sHLD group, 4.1% in the dHLD group, and 4.2% in the HLD/ETO group (P = .36). MRDOs were cultured from 3.2% of pre-procedure rectal swabs and 2.5% of duodenal aspirates. In a comparison of duodenoscopes reprocessed by sHLD, dHLD, or HLD/ETO, we found no significant differences between groups for MDRO or bacteria contamination. Enhanced disinfection methods (dHLD or HLD/ETO) did not provide additional protection against contamination. However, insufficient events occurred to assess our primary study end

Rad51 recombinase prevents Mre11 nuclease-dependent degradation and excessive PrimPol-mediated elongation of nascent DNA after UV irradiation

PubMed Central

Vallerga, María Belén; Mansilla, Sabrina F.; Federico, María Belén; Bertolin, Agustina P.; Gottifredi, Vanesa

2015-01-01

After UV irradiation, DNA polymerases specialized in translesion DNA synthesis (TLS) aid DNA replication. However, it is unclear whether other mechanisms also facilitate the elongation of UV-damaged DNA. We wondered if Rad51 recombinase (Rad51), a factor that escorts replication forks, aids replication across UV lesions. We found that depletion of Rad51 impairs S-phase progression and increases cell death after UV irradiation. Interestingly, Rad51 and the TLS polymerase polη modulate the elongation of nascent DNA in different ways, suggesting that DNA elongation after UV irradiation does not exclusively rely on TLS events. In particular, Rad51 protects the DNA synthesized immediately before UV irradiation from degradation and avoids excessive elongation of nascent DNA after UV irradiation. In Rad51-depleted samples, the degradation of DNA was limited to the first minutes after UV irradiation and required the exonuclease activity of the double strand break repair nuclease (Mre11). The persistent dysregulation of nascent DNA elongation after Rad51 knockdown required Mre11, but not its exonuclease activity, and PrimPol, a DNA polymerase with primase activity. By showing a crucial contribution of Rad51 to the synthesis of nascent DNA, our results reveal an unanticipated complexity in the regulation of DNA elongation across UV-damaged templates. PMID:26627254

Genetic differentiation and forensic efficiency evaluation for Chinese Salar ethnic minority based on a 5-dye multiplex insertion and deletion panel.

PubMed

Ma, Ruilin; Shen, Chunmei; Wei, Yuanyuan; Jin, Xiaoye; Guo, Yuxin; Mu, Yuling; Sun, Siqi; Chen, Chong; Cui, Wei; Wei, Zhaoming; Lian, Zhenmin

2018-06-20

The present study investigated the genetic diversities of 30 autosomal insertion and deletion (InDel) loci of Investigator DIPplex kit (Qiagen) in Chinese Salar ethnic minority and explored the genetic relationships between the studied Salar group and other populations. The allelic frequencies of deletion alleles at the 30 InDel loci were in the range of 0.1739 (HLD64) to 0.8478 (HLD39). The discrimination power, polymorphism information content and probability of exclusion ranged from 0.4101 (HLD39) to 0.6447 (HLD136), 0.2247 (HLD39) to 0.3750 (HLD92) and 0.0400 (HLD39) to 0.2806 (HLD92), respectively. The observed and expected heterozygosity were in the range of 0.2348 (HLD39) to 0.5913 (HLD92), and 0.2580 (HLD39) to 0.5000 (HLD92), respectively. The cumulative discrimination power and probability of exclusion of the 30 loci reached 0.999999999993418 and 0.99039, respectively. The results of population genetic differentiation comparisons revealed that Salar group had similar allele distributions with Qinghai Tibetan, Xibe and Yi groups. Population Bayesian cluster analysis showed that there were similar ancestry components between Salar group and most Chinese populations. Besides, the principal components analysis and phylogenetic reconstructions further indicated that Salar group had intimate genetic relationships with Qinghai Tibetan and Xibe groups. In short, the results of the current studies indicated the genetic distributions of the 30 InDel loci in Salar group were relatively high genetic polymorphisms, which could be used in forensic individual identifications and as a supplementary tool for complex paternity testing. Copyright © 2018 Elsevier B.V. All rights reserved.

Nascent starbursts: a missing link in galaxy evolution

NASA Astrophysics Data System (ADS)

Roussel, Helene; Beck, Rainer; Condon, Jim; Helou, George; Smith, John-David

2005-06-01

We have identified a rare category of galaxies characterized by an extreme deficiency in synchro- tron radiation, relative to dust emission, and very high dust temperatures. We studied in detail the most extreme such object, and concluded in favor of a starburst just breaking out, less than one megayear old, in a galaxy having undergone no major star formation episode in the last 100 Myr. Such systems offer a perfect setting to study the initial conditions and early dynamics of starbursts and understand better the regulation of the infrared-radio continuum correlation in galaxies. For the prototypical nascent starburst, the mid-infrared spectrum is quite peculiar, suggesting tran- sient dust species and high optical depth; tracers of dust and molecular gas are the only indicators of unusual activity, and the active regions are likely very compact and dust-bounded, suppressing ionization. Only Spitzer data can provide the needed physical diagnostics for such regions. A sample of 25 nascent starbursts was drawn from the cross-correlation of the IRAS Faint Source Catalog and the NVSS VLA radio survey, and carefully selected based on our multi-wavelength VLA maps to span a range of infrared to radio ratios and luminosities. This sample allows a first step beyond studying prototypes toward a statistical analysis addressing systematic physical pro- perties, classification and search for starburst development sequences. We propose imaging and spectroscopic observations from 3 to 160 microns to characterize the state of the interstellar medium and the gas and dust excitation origin. Our aim is to learn from these unique systems how a star formation burst may develop in its very earliest phases, how it affects the fueling material and the host galaxy. Acquired observations of the radio continuum, cold molecular gas and tracers of shocks and HII regions will help us interpret the rich Spitzer data set and extract a coherent picture of the interstellar medium in our targets.

A voxel-based asymmetry study of the relationship between hemispheric asymmetry and language dominance in Wada tested patients.

PubMed

Keller, Simon S; Roberts, Neil; Baker, Gus; Sluming, Vanessa; Cezayirli, Enis; Mayes, Andrew; Eldridge, Paul; Marson, Anthony G; Wieshmann, Udo C

2018-03-23

Determining the anatomical basis of hemispheric language dominance (HLD) remains an important scientific endeavor. The Wada test remains the gold standard test for HLD and provides a unique opportunity to determine the relationship between HLD and hemispheric structural asymmetries on MRI. In this study, we applied a whole-brain voxel-based asymmetry (VBA) approach to determine the relationship between interhemispheric structural asymmetries and HLD in a large consecutive sample of Wada tested patients. Of 135 patients, 114 (84.4%) had left HLD, 10 (7.4%) right HLD, and 11 (8.2%) bilateral language representation. Fifty-four controls were also studied. Right-handed controls and right-handed patients with left HLD had comparable structural brain asymmetries in cortical, subcortical, and cerebellar regions that have previously been documented in healthy people. However, these patients and controls differed in structural asymmetry of the mesial temporal lobe and a circumscribed region in the superior temporal gyrus, suggesting that only asymmetries of these regions were due to brain alterations caused by epilepsy. Additional comparisons between patients with left and right HLD, matched for type and location of epilepsy, revealed that structural asymmetries of insula, pars triangularis, inferior temporal gyrus, orbitofrontal cortex, ventral temporo-occipital cortex, mesial somatosensory cortex, and mesial cerebellum were significantly associated with the side of HLD. Patients with right HLD and bilateral language representation were significantly less right-handed. These results suggest that structural asymmetries of an insular-fronto-temporal network may be related to HLD. © 2018 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

High-density lipoprotein cholesterol subfractions and lecithin: cholesterol acyltransferase activity in collegiate soccer players.

PubMed

Imamura, H; Nagata, A; Oshikata, R; Yoshimura, Y; Miyamoto, N; Miyahara, K; Oda, K; Iide, K

2013-05-01

Many of the published data on the lipid profile of athletes is based on studies of endurance athletes. The data on soccer players are rare. The purpose of this study was to examine serum high-density lipoprotein cholesterol subfractions and lecithin:cholesterol acyltransferase activity in collegiate soccer players. 31 well-trained male collegiate soccer players were divided into 2 groups: 16 defenders and 15 offenders. They were compared with 16 sedentary controls. Dietary information was obtained with a food frequency questionnaire. The subjects were all non-smokers and were not taking any drug known to affect the lipid and lipoprotein metabolism. The offenders had significantly higher high-density lipoprotein cholesterol, high-density lipoprotein2 cholesterol, and apolipoprotein A-I than the defenders and controls, whereas the defenders had the significantly higher high-density lipoprotein2 cholesterol than the controls. Both groups of athletes had significantly higher lecithin:cholesterol acyltransferase activity than the controls. The results indicate that favorable lipid and lipoprotein profile could be obtained by vigorous soccer training. © Georg Thieme Verlag KG Stuttgart · New York.

Protective Effect of High Molecular Weight Protein Sub-fraction of Calotropis procera Latex in Monoarthritic Rats.

PubMed

Chaudhary, Priyanka; Ramos, Marcio V; Vasconcelos, Mirele da Silveira; Kumar, Vijay L

2016-05-01

Proteins present in the latex of Calotropis procera have been shown to produce anti-inflammatory effect and to afford protection in various disease models. To determine the efficacy of high molecular weight protein sub-fraction (LPPI) of latex of C. procera in ameliorating joint inflammation and hyperalgesia in a preclinical model of arthritis. Monoarthritis was induced in rats by intra-articular injection of Freund's complete adjuvant (FCA) and the effect of two doses of LPPI (5 and 25 mg/kg) and diclofenac (5 mg/kg) was evaluated on joint swelling, stair climbing ability, motility, and dorsal flexion pain on day 3. The rats were sacrificed on day 3 to measure tissue levels of reduced glutathione (GSH) and thiobarbituric acid reactive substances (TBARS). Evaluation of joint histology was also made. Intra-articular injection of FCA produced joint swelling and difficulty in stair climbing ability, motility, and pain on flexion of the joint as revealed by scores obtained for these functional parameters. LPPI produced a dose-dependent decrease in joint swelling and improved joint functions. Arthritic rats also revealed altered oxidative homeostasis where joint tissue GSH levels were decreased and TBARS levels were increased as compared to normal rats. The levels of these oxidative stress markers were near normal in arthritic rats treated with LPPI. Moreover, treatment with LPPI also maintained the structural integrity of the joint. The protective effect of LPPI was comparable to the standard anti-inflammatory drug, diclofenac. The findings of the present study show that LPPI fraction comprising high molecular weight proteins could be used for the alleviation of arthritic symptoms. High molecular weight protein sub-fraction of latex of Calotropis procera (LPPI) reduced joint swelling and hyperalgesia in arthritic ratsLPPI produced a significant improvement in stair climbing ability and motility in arthritic ratsLPPI normalized the levels of oxidative stress markers in

Viability of randomized skin flaps-an experimental study in rats.

PubMed

António, Nsingi N; Monte Alto Costa, Andréa; Marques, Ruy G

2017-01-01

Randomized skin flaps are extensively used in plastic surgery, but the possibility of necrosis has challenged their use. Several studies have been conducted aiming to find ways to reduce the occurrence of necrosis. We evaluated the effects of pentoxifylline (PTX) and hyaluronidase (HLD), each alone or combined, on randomized rat skin flaps. Fifty male Wistar rats were divided into five groups of 10 animals each: control I, control II, PTX, HLD, PTX-HLD. Substances were administered from the first to the 14th postoperative day. The necrotic area was measured on the seventh and 14th postoperative day; the animals were killed on the 14th day, when samples were collected for histologic and immunohistochemical examination. On the seventh day, percentage of the necrotic area was significantly reduced in PTX, HLD, and PTX-HLD animals compared with control groups. On 14th day, percentage of the necrotic area in PTX, HDL, and PTX-HLD groups was also significantly reduced compared with control groups. PTX and PTX-HLD showed a significant reduction in dermis cellularity, V V of macrophages, and myofibroblasts compared with control groups; PTX showed a significant enhancement of L V of blood vessels compared with all other groups. The use of each substance alone or combined increased flap viability compared with control groups. On the seventh day, PTX exhibited lower viability than HLD, whereas on the 14th day there was no difference between treated groups. PTX alone enhanced the L V of blood vessels, whereas PTX-HLD did not. However, PTX-HLD was more effective in decreasing the dermis cellularity and macrophage V V than HLD alone. Copyright © 2016 Elsevier Inc. All rights reserved.

The Fluid Dynamics of Nascent Biofilms

NASA Astrophysics Data System (ADS)

Farthing, Nicola; Snow, Ben; Wilson, Laurence; Bees, Martin

2017-11-01

Many anti-biofilm approaches target mature biofilms with biochemical or physio-chemical interventions. We investigate the mechanics of interventions at an early stage that aim to inhibit biofilm maturation, focusing on hydrodynamics as cells transition from planktonic to surface-attached. Surface-attached cells generate flow fields that are relatively long-range compared with cells that are freely-swimming. We look at the effect of these flows on the biofilm formation. In particular, we use digital inline holographic microscopy to determine the three-dimensional flow due to a surface-attached cell and the effect this flow has on both tracers and other cells in the fluid. We compare experimental data with two models of cells on boundaries. The first approach utilizes slender body theory and captures many of the features of the experimental field. The second model develops a simple description in terms of singularity solutions of Stokes' flow, which produces qualitatively similar dynamics to both the experiments and more complex model but with significant computational savings. The range of validity of multiple cell arrangements is investigated. These two descriptions can be used to investigate the efficacy of actives developed by Unilever on nascent biofilms.

SWI/SNF Associates with Nascent Pre-mRNPs and Regulates Alternative Pre-mRNA Processing

PubMed Central

Tyagi, Anu; Ryme, Jessica; Brodin, David; Östlund Farrants, Ann Kristin; Visa, Neus

2009-01-01

The SWI/SNF chromatin remodeling complexes regulate the transcription of many genes by remodeling nucleosomes at promoter regions. In Drosophila, SWI/SNF plays an important role in ecdysone-dependent transcription regulation. Studies in human cells suggest that Brahma (Brm), the ATPase subunit of SWI/SNF, regulates alternative pre-mRNA splicing by modulating transcription elongation rates. We describe, here, experiments that study the association of Brm with transcribed genes in Chironomus tentans and Drosophila melanogaster, the purpose of which was to further elucidate the mechanisms by which Brm regulates pre-mRNA processing. We show that Brm becomes incorporated into nascent Balbiani ring pre-mRNPs co-transcriptionally and that the human Brm and Brg1 proteins are associated with RNPs. We have analyzed the expression profiles of D. melanogaster S2 cells in which the levels of individual SWI/SNF subunits have been reduced by RNA interference, and we show that depletion of SWI/SNF core subunits changes the relative abundance of alternative transcripts from a subset of genes. This observation, and the fact that a fraction of Brm is not associated with chromatin but with nascent pre-mRNPs, suggest that SWI/SNF affects pre-mRNA processing by acting at the RNA level. Ontology enrichment tests indicate that the genes that are regulated post-transcriptionally by SWI/SNF are mostly enzymes and transcription factors that regulate postembryonic developmental processes. In summary, the data suggest that SWI/SNF becomes incorporated into nascent pre-mRNPs and acts post-transcriptionally to regulate not only the amount of mRNA synthesized from a given promoter but also the type of alternative transcript produced. PMID:19424417

Probing the Role of Nascent Helicity in p27 Function as a Cell Cycle Regulator

PubMed Central

Otieno, Steve; Kriwacki, Richard

2012-01-01

p27 regulates the activity of Cdk complexes which are the principal governors of phase transitions during cell division. Members of the p27 family of proteins, which also includes p21 and p57, are called the Cip/Kip cyclin-dependent kinase regulators (CKRs). Interestingly, the Cip/Kip CKRs play critical roles in cell cycle regulation by being intrinsically unstructured, a characteristic contrary to the classical structure-function paradigm. They exhibit nascent helicity which has been localized to a segment referred to as sub-domain LH. The nascent helicity of this sub-domain is conserved and we hypothesize that it is an important determinant of their functional properties. To test this hypothesis, we successfully designed and prepared p27 variants in which domain LH was either more or less helical with respect to the wild-type protein. Thermal denaturation experiments showed that the ternary complexes of the p27 variants bound to Cdk2/Cyclin A were less stable compared to the wild-type complex. Isothermal titration calorimetry experiments showed a decrease in the enthalpy of binding for all the mutants with respect to p27. The free energies of binding varied within a much narrower range. In vitro Cdk2 inhibition assays showed that the p27 variants exhibited disparate inhibitory potencies. Furthermore, when over-expressed in NIH 3T3 mouse fibroblast cells, the less helical p27 variants were less effective in causing cell cycle arrest relative to the wild-type p27. Our results indicate that the nascent helicity of sub-domain LH plays a key role mediating the biological function of p27. PMID:23071750

Live Cell Imaging of the Nascent Inactive X Chromosome during the Early Differentiation Process of Naive ES Cells towards Epiblast Stem Cells

PubMed Central

Guyochin, Aurélia; Maenner, Sylvain; Chu, Erin Tsi-Jia; Hentati, Asma; Attia, Mikael; Avner, Philip; Clerc, Philippe

2014-01-01

Random X-chromosome inactivation ensures dosage compensation in mammals through the transcriptional silencing of one of the two X chromosomes present in each female cell. Silencing is initiated in the differentiating epiblast of the mouse female embryos through coating of the nascent inactive X chromosome by the non-coding RNA Xist, which subsequently recruits the Polycomb Complex PRC2 leading to histone H3-K27 methylation. Here we examined in mouse ES cells the early steps of the transition from naive ES cells towards epiblast stem cells as a model for inducing X chromosome inactivation in vitro. We show that these conditions efficiently induce random XCI. Importantly, in a transient phase of this differentiation pathway, both X chromosomes are coated with Xist RNA in up to 15% of the XX cells. In an attempt to determine the dynamics of this process, we designed a strategy aimed at visualizing the nascent inactive X-chromosome in live cells. We generated transgenic female XX ES cells expressing the PRC2 component Ezh2 fused to the fluorescent protein Venus. The fluorescent fusion protein was expressed at sub-physiological levels and located in nuclei of ES cells. Upon differentiation of ES cell towards epiblast stem cell fate, Venus-fluorescent territories appearing in interphase nuclei were identified as nascent inactive X chromosomes by their association with Xist RNA. Imaging of Ezh2-Venus for up to 24 hours during the differentiation process showed survival of some cells with two fluorescent domains and a surprising dynamics of the fluorescent territories across cell division and in the course of the differentiation process. Our data reveal a strategy for visualizing the nascent inactive X chromosome and suggests the possibility for a large plasticity of the nascent inactive X chromosome. PMID:25546018

A Primer on the Pathway to Scholarly Writing: Helping Nascent Writers to Unlearn Conditioned Habits

ERIC Educational Resources Information Center

McDougall, Dennis; Ornelles, Cecily; Rao, Kavita

2015-01-01

In this article, we identify eight common error patterns of nascent writers when they attempt to navigate the pathway to scholarly writing. We illustrate each error pattern via examples and counter-examples (corrections). We also describe how to identify such patterns, why those patterns might occur and persist, and why each pattern is…

Revised Healthy Lifestyle-Diet Index and associations with obesity and iron deficiency in schoolchildren: The Healthy Growth Study.

PubMed

Manios, Y; Moschonis, G; Papandreou, C; Politidou, E; Naoumi, A; Peppas, D; Mavrogianni, C; Lionis, C; Chrousos, G P

2015-02-01

The Healthy Lifestyle-Diet Index (HLD-index), previously developed to assess the degree of adherence to dietary and lifestyle guidelines for primary schoolchildren, was revised according to updated recommendations. Τhe association of the revised HLD-index (R-HLD-index) with obesity and iron deficiency (ID) was also examined. A representative sample of 2660 primary schoolchildren from Greece (9-13 years old) participating in the 'Healthy Growth Study' was examined. Twelve components related to dietary and lifestyle patterns were used to develop the R-HLD-index. Scores from 0 up to 4 were assigned to each one of these components, giving a total score ranging from 0 to 48. The associations between the R-HLD-index, obesity and ID were examined via logistic regression analysis. The total score of the R-HLD-index calculated for each one of the study participants was found to range between 2 and 32 units, with higher scores being indicative of a healthier lifestyle and better diet quality. After adjusting for potential confounders, logistic regression analysis showed that an increase in the R-HLD-index score by one unit was associated with 6% lower odds for obesity. However, no significant association was observed between the R-HLD-index score and ID. The R-HLD-index may be a useful tool for public health policy makers and healthcare professionals when assessing diet quality and lifestyle patterns of primary schoolchildren. Identification of children with lower scores in the R-HLD-index and its individual components could guide tailored made interventions targeting specific children and behaviors. © 2013 The British Dietetic Association Ltd.

A novel compound inhibits rHDL assembly and blocks nascent HDL biogenesis downstream of apoAI binding to ABCA1 expressing cells

PubMed Central

Lyssenko, Nicholas N.; Brubaker, Gregory; Smith, Bradley D.; Smith, Jonathan D.

2011-01-01

Objective Nascent high-density lipoprotein (HDL) particles form from cellular lipids and extracellular lipid-free apolipoprotein AI (apoAI) in a process mediated by ATP-binding cassette transporter A1 (ABCA1). We have sought out compounds that inhibit nascent HDL biogenesis without affecting ABCA1 activity. Methods and Results Reconstituted HDL (rHDL) formation and cellular cholesterol efflux assays were used to show that two compounds that bond via hydrogen with phospholipids inhibit rHDL and nascent HDL production. In rHDL formation assays, the inhibitory effect of compound 1 (methyl 3α-acetoxy-7α,12α-di[(phenylaminocarbonyl)amino]-5β-cholan-24-oate), the more active of the two, depended on its ability to associate with phospholipids. In cell assays, compound 1 suppressed ABCA1-mediated cholesterol efflux to apoAI, the 18A peptide, and taurocholate with high specificity, without affecting ABCA1-independent cellular cholesterol efflux to HDL and endocytosis of acetylated low-density lipoprotein (AcLDL) and transferrin. Furthermore, compound 1 did not affect ABCA1 activity adversely, as ABCA1-mediated shedding of microparticles proceeded unabated and apoAI binding to ABCA1-expressing cells increased in its presence. Conclusions The inhibitory effects of compound 1 support a three-step model of nascent HDL biogenesis: plasma membrane remodeling by ABCA1, apoAI binding to ABCA1, and lipoprotein particle assembly. The compound inhibits the final step, causing accumulation of apoAI in ABCA1-expressing cells. PMID:21836073

Splicing-independent loading of TREX on nascent RNA is required for efficient expression of dual-strand piRNA clusters in Drosophila

PubMed Central

Hur, Junho K.; Luo, Yicheng; Moon, Sungjin; Ninova, Maria; Marinov, Georgi K.; Chung, Yun D.; Aravin, Alexei A.

2016-01-01

The conserved THO/TREX (transcription/export) complex is critical for pre-mRNA processing and mRNA nuclear export. In metazoa, TREX is loaded on nascent RNA transcribed by RNA polymerase II in a splicing-dependent fashion; however, how TREX functions is poorly understood. Here we show that Thoc5 and other TREX components are essential for the biogenesis of piRNA, a distinct class of small noncoding RNAs that control expression of transposable elements (TEs) in the Drosophila germline. Mutations in TREX lead to defects in piRNA biogenesis, resulting in derepression of multiple TE families, gametogenesis defects, and sterility. TREX components are enriched on piRNA precursors transcribed from dual-strand piRNA clusters and colocalize in distinct nuclear foci that overlap with sites of piRNA transcription. The localization of TREX in nuclear foci and its loading on piRNA precursor transcripts depend on Cutoff, a protein associated with chromatin of piRNA clusters. Finally, we show that TREX is required for accumulation of nascent piRNA precursors. Our study reveals a novel splicing-independent mechanism for TREX loading on nascent RNA and its importance in piRNA biogenesis. PMID:27036967

Gravitational radiation from rapidly rotating nascent neutron stars

NASA Technical Reports Server (NTRS)

Lai, Dong; Shapiro, Stuart L.

1995-01-01

We study the secular evolution and gravitational wave signature of a newly formed, rapidly rotating neutron star. The neutron star may arise from core collapse in a massive star or from the accretion-induced collapse of a white dwarf. After a brief dynamical phase, the nascent neutron star settles into an axisymmetric, secularly unstable state. Gravitational radiation drives the star to a nonaxisymmetric, stationary equilibrium configuration via the bar-mode instability. The emitted quasi-periodic gravitational waves have a unique signature: the wave frequency sweeps downward from a few hundred Hertz to zero, while the wave amplitude increase from zero to a maximum and then decays back to zero. Such a wave signal could detected by broadband gravitational wave interferometers currently being constructed. We also characterize two other types of gravitational wave signals that could arise in principle from a rapidly rotating, secularly unstable neutron star: a high-frequency (f greater than or approximately = 1000 Hz) wave which increases the pattern-speed of the star, and a wave that actually increases the angular momentum of the star.

Does Ethicality Wane with Adulthood? A Study of the Ethical Values of Entrepreneurship Students and Nascent Entrepreneurs

ERIC Educational Resources Information Center

Lourenço, Fernando; Sappleton, Natalie; Cheng, Ranis

2015-01-01

The authors examined the following questions: Does gender influence the ethicality of enterprise students to a greater extent than it does nascent entrepreneurs? If this is the case, then is it due to factors associated with adulthood such as age, work experience, marital status, and parental status? Sex-role socialization theory and moral…

Effects of short-term modest weight loss on fasting and post-prandial lipoprotein sub-fractions in type 2 diabetes mellitus patients.

PubMed

Ybarra, J; James, R W; Makoundou, V; Bioletto, S; Golay, A

2001-12-01

We assessed the efficacy of a modest weight loss (1.5 +/- 0.3 kg) and simultaneous rapid improvement in glycemic control on fasting an post-prandial lipoprotein sub-fractions in nine overweight (BMI=28 +/- 1.7 kg/m(2)) well controlled Type 2 diabetic patients (HbA(1c)=7.3 +/- 0.1%). They followed a non-drastical hypocaloric balanced diet (1 561 +/- 39 kcal/day) over ten days in hospital. The fat content of the diet was significantly lowered from 96 +/- 12 g/day to 62 +/- 4 g/day (p<0.03). Plasma lipid and lipoprotein levels were measured in fasting and four hours after standard breakfast and four hours after standard lunch twice before and after ten days of hospitalization. The sub-fractions of very low density and low density lipoprotein were obtained by cumulative flotation ultracentrifugation. This weight loss reduced two well known independent cardiovascular risk factors such as the post-prandial glycemic excursions (p<0.05) and the post-prandial lipemia (p<0.05). Multiple linear regression analyses identified weight loss as an independent variable accounting for the ability to predict post-prandial capillary triglyceride clearance (p<0.05). Improvements in post-prandial glycemic excursions which was also entered as a parameter did not appear as a variable being able to predict these changes (p=0.4). In addition to the 23% improvement in post-prandial capillary triglyceride clearance (p<0.02), a decrement in post-prandial VLDL-2 triglyceride enrichment was found (p<0.05). Finally, fasting and post-prandial LDL-3 cholesterol levels were diminished (p<0.05) and the LDL-2/LDL-3 mass ratio post-prandial kinetics were improved (p<0.05). Even a modest weight loss in overweight, average controlled type 2 diabetic patients can achieve a significant improvement in two cardiovascular risk factors, namely post-prandial triglyceride excursions and the LDL-2/LDL-3 mass ratio kinetics independently from glycemic control improvements.

Treatment patterns in hyperlipidaemia patients based on administrative claim databases in Japan.

PubMed

Wake, Mayumi; Onishi, Yoshie; Guelfucci, Florent; Oh, Akinori; Hiroi, Shinzo; Shimasaki, Yukio; Teramoto, Tamio

2018-05-01

Real-world evidence on treatment of hyperlipidaemia (HLD) in Japan is limited. We aimed to describe treatment patterns, persistence with, and adherence to treatment in Japanese patients with HLD. Retrospective analyses of adult HLD patients receiving drug therapy in 2014-2015 were conducted using the Japan Medical Data Center (JMDC) and Medical Data Vision (MDV) databases. Depending on their HLD treatment history, individuals were categorised as untreated (UT) or previously treated (PT), and were followed for at least 12 months. Outcomes of interest included prescribing patterns of HLD drug classes, persistence with treatment at 12 months, and adherence to treatment. Data for 49,582 and 53,865 patients from the JMDC and MDV databases, respectively, were analysed. First-line HLD prescriptions for UT patients were predominantly for moderate statins (JMDC: 75.9%, MDV: 77.0%). PT patients most commonly received combination therapy (JMDC: 43.9%, MDV: 52.6%). Approximately half of the UT patients discontinued treatment during observation. Within each cohort, persistence rates were lower in UT patients than in PT patients (JMDC: 45.0% vs. 77.5%; MDV: 51.9% vs. 85.3%). Adherence was ≥80% across almost all HLD drug classes, and was slightly lower in the JMDC cohort than MDV cohort. Most common prescriptions were moderate statins in UT patients and combination therapy in PT patients. The high discontinuation rate of HLD therapy in UT patients warrants further investigation and identification of methods to encourage and support long-term persistence. Copyright © 2018. Published by Elsevier B.V.

Self-assembly of marine exudate particles and their impact on the CCN properties of nascent marine aerosol

NASA Astrophysics Data System (ADS)

Schill, S.; Zimmermann, K.; Ryder, O. S.; Campbell, N.; Collins, D. B.; Gianneschi, N.; Bertram, T. H.

2013-12-01

Spontaneous self-assembly of marine exudate particles has previously been observed in filtered seawater samples. The chemicophysical properties of these particles may alter the chemical composition and CCN properties of nascent marine aerosol, yet to date simultaneous measurement of seawater exudate particle formation rates and number distributions, with aerosol particle formation rates and CCN activity are lacking. Here, we use a novel Marine Aerosol Reference Tank (MART) system to experimentally mimic a phytoplankton bloom via sequential addition of biological surrogates, including sterol, galactose, lipopolysaccharide, BSA protein, and dipalmitoylphosphatidylcholine. Nascent sea-spray aerosol are generated in the MART system via a continuous plunging waterfall. Exudate particle assembly in the water is monitored via dynamic light scattering (DLS) and transmission electron microscopy (TEM) to obtain both the assembly kinetics of the particles as well as particle number distributions Simultaneous characterization of both particle production rates and super-saturated particle hygroscopicity are also discussed. This study permits analysis of the controlling role of the molecular composition of dissolved organic carbon in setting the production rates of colloidal material in the surface oceans.

The Exosome Associates Cotranscriptionally with the Nascent Pre-mRNP through Interactions with Heterogeneous Nuclear Ribonucleoproteins

PubMed Central

Hessle, Viktoria; Björk, Petra; Sokolowski, Marcus; de Valdivia, Ernesto González; Silverstein, Rebecca; Artemenko, Konstantin; Tyagi, Anu; Maddalo, Gianluca; Ilag, Leopold; Helbig, Roger; Zubarev, Roman A.

2009-01-01

Eukaryotic cells have evolved quality control mechanisms to degrade aberrant mRNA molecules and prevent the synthesis of defective proteins that could be deleterious for the cell. The exosome, a protein complex with ribonuclease activity, is a key player in quality control. An early quality checkpoint takes place cotranscriptionally but little is known about the molecular mechanisms by which the exosome is recruited to the transcribed genes. Here we study the core exosome subunit Rrp4 in two insect model systems, Chironomus and Drosophila. We show that a significant fraction of Rrp4 is associated with the nascent pre-mRNPs and that a specific mRNA-binding protein, Hrp59/hnRNP M, interacts in vivo with multiple exosome subunits. Depletion of Hrp59 by RNA interference reduces the levels of Rrp4 at transcription sites, which suggests that Hrp59 is needed for the exosome to stably interact with nascent pre-mRNPs. Our results lead to a revised mechanistic model for cotranscriptional quality control in which the exosome is constantly recruited to newly synthesized RNAs through direct interactions with specific hnRNP proteins. PMID:19494042

Binding of transcription termination protein nun to nascent RNA and template DNA.

PubMed

Watnick, R S; Gottesman, M E

1999-12-17

The amino-terminal arginine-rich motif of coliphage HK022 Nun binds phage lambda nascent transcript, whereas the carboxyl-terminal domain interacts with RNA polymerase (RNAP) and blocks transcription elongation. RNA binding is inhibited by zinc (Zn2+) and stimulated by Escherichia coli NusA. To study these interactions, the Nun carboxyl terminus was extended by a cysteine residue conjugated to a photochemical cross-linker. The carboxyl terminus contacted NusA and made Zn2+-dependent intramolecular contacts. When Nun was added to a paused transcription elongation complex, it cross-linked to the DNA template. Nun may arrest transcription by anchoring RNAP to DNA.

Moist and dry heating-induced changes in protein molecular structure, protein subfractions, and nutrient profiles in camelina seeds.

PubMed

Peng, Quanhui; Khan, Nazir A; Wang, Zhisheng; Yu, Peiqiang

2014-01-01

The objectives of the present study were to investigate the nutritive value of camelina seeds (Camelina sativa L. Crantz) in ruminant nutrition and to use molecular spectroscopy as a novel technique to quantify the heat-induced changes in protein molecular structures in relation to protein digestive behavior in the rumen and intestine of dairy cattle. In this study, camelina seeds were used as a model for feed protein. The seeds were kept as raw (control) or heated in an autoclave (moist heating) or in an air-draft oven (dry heating) at 120°C for 60 min. The parameters evaluated were (1) chemical profiles, (2) Cornell Net Protein and Carbohydrate System protein subfractions, (3) nutrient digestibilities and estimated energy values, (4) in situ rumen degradation and intestinal digestibility, and (5) protein molecular structures. Compared with raw seeds, moist heating markedly decreased (52.73 to 20.41%) the content of soluble protein and increased (2.00 to 9.01%) the content of neutral detergent insoluble protein in total crude protein (CP). Subsequently, the rapidly degradable Cornell Net Protein and Carbohydrate System CP fraction markedly decreased (45.06 to 16.69% CP), with a concomitant increase in the intermediately degradable (45.28 to 74.02% CP) and slowly degradable (1.13 to 8.02% CP) fractions, demonstrating a decrease in overall protein degradability in the rumen. The in situ rumen incubation study revealed that moist heating decreased (75.45 to 57.92%) rumen-degradable protein and increased (43.90 to 82.95%) intestinal digestibility of rumen-undegradable protein. The molecular spectroscopy study revealed that moist heating increased the amide I-to-amide II ratio and decreased α-helix and α-helix-to-β-sheet ratio. In contrast, dry heating did not significantly change CP solubility, rumen degradability, intestinal digestibility, and protein molecular structures compared with the raw seeds. Our results indicated that, compared with dry heating, moist

Effect of Heating Method on Alteration of Protein Molecular Structure in Flaxseed: Relationship with Changes in Protein Subfraction Profile and Digestion in Dairy Cows.

PubMed

Ahmad Khan, Nazir; Booker, Helen; Yu, Peiqiang

2015-02-04

This study evaluated the effect of heating methods on alteration of protein molecular structure in flaxseed (Linum usitatissimum L.) in relation to changes in protein subfraction profile and digestion in dairy cows. Seeds from two flaxseed varieties, sampled from two replicate plots at two locations, were evaluated. The seeds were either maintained in their raw state or heated in an air-draft oven (dry heating) or autoclave (moist heating) for 60 min at 120 °C or by microwave irradiation (MIR) for 5 min. Compared to raw seeds, moist heating decreased (P < 0.05) soluble protein (SP) content [56.5 ± 5.55 to 25.9 ± 6.16% crude protein (CP)] and increased (P < 0.05) rumen undegraded protein (RUP) content (36.0 ± 5.19 to 46.9 ± 2.72% CP) and intestinal digestibility of RUP (61.0 ± 2.28 to 63.8 ± 2.67% RUP). Dry heating did not alter (P > 0.05) the protein subfraction profile and rumen degradation kinetics, whereas MIR increased (P < 0.05) the RUP content from 36.0 ± 5.19 to 40.4 ± 4.67% CP. The MIR and dry heating did not alter (P > 0.05) the amide I to amide II ratio, but moist heating decreased (P < 0.05) both the amide I to amide II ratio and α-helix-to-β-sheet ratio. Regression equations based on protein molecular spectral intensities provided high prediction power for estimation of heat-induced changes in SP (R 2 = 0.62), RUP (R 2 = 0.71), and intestinal digestibility of RUP (R 2 = 0.72). Overall, heat-induced changes in protein nutritive value and digestion were strongly associated with heat-induced alteration in protein molecular structures.

Performance Optimization of Irreversible Air Heat Pumps Considering Size Effect

NASA Astrophysics Data System (ADS)

Bi, Yuehong; Chen, Lingen; Ding, Zemin; Sun, Fengrui

2018-06-01

Considering the size of an irreversible air heat pump (AHP), heating load density (HLD) is taken as thermodynamic optimization objective by using finite-time thermodynamics. Based on an irreversible AHP with infinite reservoir thermal-capacitance rate model, the expression of HLD of AHP is put forward. The HLD optimization processes are studied analytically and numerically, which consist of two aspects: (1) to choose pressure ratio; (2) to distribute heat-exchanger inventory. Heat reservoir temperatures, heat transfer performance of heat exchangers as well as irreversibility during compression and expansion processes are important factors influencing on the performance of an irreversible AHP, which are characterized with temperature ratio, heat exchanger inventory as well as isentropic efficiencies, respectively. Those impacts of parameters on the maximum HLD are thoroughly studied. The research results show that HLD optimization can make the size of the AHP system smaller and improve the compactness of system.

The relationship between migraine and lipid sub-fractions among individuals without cardiovascular disease: A cross-sectional evaluation in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

PubMed

Goulart, Alessandra C; Lotufo, Paulo A; Santos, Itamar S; Bittencourt, Márcio S; Santos, Raul D; Blaha, Michael J; Jones, Steven; Toth, Peter P; Kulkarni, Krishnaji; Benseñor, Isabela M

2018-03-01

Introduction Recent studies have explored the relationship between dyslipidemia and migraine in a cardiovascular context. Thus, we aimed to evaluate the possible association between lipids, lipoprotein subfractions and migraine according to aura symptoms in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Methods 1,560 women and 1,595 men, without CVD or lipid disorders requiring medication, underwent a baseline clinical assessment. Total-cholesterol and its sub-fractions (LDL, VLDL and HDL subclass cholesterol); triglycerides and triglyceride-rich lipoprotein cholesterol [TRL-C (VLDL 1+2 -C VLDL 3 -C + IDL-C)] were determined by vertical auto profile (VAP). We also calculated logarithmic LDL density ratio [LLDR = ln ((LDL 3 -C + LDL 4 -C)/(LDL 1 -C + LDL 2 -C))], T-Chol/HDL-C and triglycerides/HDL-C ratios. Odds ratios (OR) with 95% confidence intervals (CI) were obtained to evaluate the relationship between lipids tertiles and migraine for both sexes. Results Main findings revealed positive associations between migraine without aura (MO) and the highest tertiles of VLDL-C (OR, 1.61; 95%CI, 1.07-2.40) and TRL-C (OR, 1.55; 95% CI, 1.03-2.34) in women. In men, the highest tertile of VLDL 3 -C (OR, 3.87; 95%CI, 1.23-12.19) was positively associated with MO, as well. Conclusions In middle-aged participants without CVD or lipid disorders requiring medication, the worst lipid profile was determined by the highest levels of TRL-C and their cholesterol-rich remnants in migraineurs without aura for both sexes.

Eccentricity Evolution of Extrasolar Multiple Planetary Systems Due to the Depletion of Nascent Protostellar Disks

NASA Astrophysics Data System (ADS)

Nagasawa, M.; Lin, D. N. C.; Ida, S.

2003-04-01

Most extrasolar planets are observed to have eccentricities much larger than those in the solar system. Some of these planets have sibling planets, with comparable masses, orbiting around the same host stars. In these multiple planetary systems, eccentricity is modulated by the planets' mutual secular interaction as a consequence of angular momentum exchange between them. For mature planets, the eigenfrequencies of this modulation are determined by their mass and semimajor axis ratios. However, prior to the disk depletion, self-gravity of the planets' nascent disks dominates the precession eigenfrequencies. We examine here the initial evolution of young planets' eccentricity due to the apsidal libration or circulation induced by both the secular interaction between them and the self-gravity of their nascent disks. We show that as the latter effect declines adiabatically with disk depletion, the modulation amplitude of the planets' relative phase of periapsis is approximately invariant despite the time-asymmetrical exchange of angular momentum between planets. However, as the young planets' orbits pass through a state of secular resonance, their mean eccentricities undergo systematic quantitative changes. For applications, we analyze the eccentricity evolution of planets around υ Andromedae and HD 168443 during the epoch of protostellar disk depletion. We find that the disk depletion can change the planets' eccentricity ratio. However, the relatively large amplitude of the planets' eccentricity cannot be excited if all the planets had small initial eccentricities.

A Proteomic Characterization of Factors Enriched at Nascent DNA Molecules

PubMed Central

Lopez-Contreras, Andres J.; Ruppen, Isabel; Nieto-Soler, Maria; Murga, Matilde; Rodriguez-Acebes, Sara; Remeseiro, Silvia; Rodrigo-Perez, Sara; Rojas, Ana M.; Mendez, Juan; Muñoz, Javier; Fernandez-Capetillo, Oscar

2013-01-01

SUMMARY DNA replication is facilitated by multiple factors that concentrate in the vicinity of replication forks. Here, we developed an approach that combines the isolation of proteins on nascent DNA chains with mass spectrometry (iPOND-MS), allowing a comprehensive proteomic characterization of the human replisome and replisome-associated factors. In addition to known replisome components, we provide a broad list of proteins that reside in the vicinity of the replisome, some of which were not previously associated with replication. For instance, our data support a link between DNA replication and the Williams-Beuren syndrome and identify ZNF24 as a replication factor. In addition, we reveal that SUMOylation is wide-spread for factors that concentrate near replisomes, which contrasts with lower UQylation levels at these sites. This resource provides a panoramic view of the proteins that concentrate in the surroundings of the replisome, which should facilitate future investigations on DNA replication and genome maintenance. PMID:23545495

Sorption mechanisms of sulfamethazine to soil humin and its subfractions after sequential treatments.

PubMed

Guo, Xiaoying; Shen, Xiaofang; Zhang, Meng; Zhang, Haiyun; Chen, Weixiao; Wang, Hui; Koelmans, A A; Cornelissen, Gerard; Tao, Shu; Wang, Xilong

2017-02-01

Sorption mechanisms of an antibiotic sulfamethazine (SMT) to humin (HM) isolated from a peat soil and its subfractions after sequential treatments were examined. The treatments of HM included removal of ash, O-alkyl carbon, lipid, and lignin components. The HF/HCl de-ashing treatment removed a large amount of minerals (mainly silicates), releasing a fraction of hydrophobic carbon sorption domains that previously were blocked, increasing the sorption of SMT by 33.3%. The de-O-alkyl carbon treatment through acid hydrolysis greatly reduced polarity of HM samples, thus weakening the interaction between sorbents with water at the interfaces via H-bonding, leaving more effective sorption sites. Sorption of SMT via mechanisms such as van der Waals forces and π-π interactions was enhanced by factors of 2.04-2.50. After removing the lipid/lignin component with the improved Soxhlet extraction/acid hydrolysis, the organic carbon content-normalized sorption enhancement index E oc was calculated. The results demonstrated that the E oc-lipid for SMT (16.9%) was higher than E oc-lignin (10.1%), implying that removal of unit organic carbon mass of lipid led to a higher increase in sorption strength than that of lignin. As each component was progressively removed from HM, the sorption strength and isotherm nonlinearity of the residual HM samples for SMT were gradually enhanced. The K oc values of SMT by HM samples were positively correlated with their aromatic carbon contents, implying that π-π electron donor-acceptor interactions between the benzene ring of sorbate and the aromatic domains in HM played a significant role in their interactions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Subcategory learning in normal and language learning-disabled adults: how much information do they need?

PubMed

Richardson, Jessica; Harris, Laurel; Plante, Elena; Gerken, Louann

2006-12-01

The purpose of this experiment was to determine if nonreferential morphophonological information was sufficient to facilitate the learning of gender subcategories (i.e., masculine vs. feminine) in individuals with normal language (NL) and those with a history of language-based learning disabilities (HLD). Thirty-two adults listened for 18 min to a familiarization set of Russian words that included either 1 (single-marked) or 2 (double-marked) morphophonological markers indicating gender. Participants were then tested on their knowledge of both trained and untrained members of each gender subcategory. Testing indicated that morphophonological information is sufficient for lexical subcategory learning in both NL and HLD groups, although the HLD group had lower overall accuracy. The HLD group benefited from double-marking relative to single-marking for subcategory learning. The results demonstrated that learning through implicit mechanisms occurred after a relatively brief exposure to the language stimuli. In addition, the weaker overall learning by the HLD group was facilitated when multiple cues to linguistic subcategory were available in the input group members received.

Adenosine triphosphate bioluminescence for bacteriological surveillance and reprocessing strategies for minimizing risk of infection transmission by duodenoscopes

PubMed Central

Sethi, Saurabh; Huang, Robert J.; Barakat, Monique T.; Banaei, Niaz; Friedland, Shai; Banerjee, Subhas

2017-01-01

Background/Aims Recent outbreaks of duodenoscope-transmitted infections underscore the importance of adequate endoscope reprocessing. Adenosine triphosphate (ATP) bioluminescence testing allows rapid evaluation of endoscopes for bacteriological/biological residue. In this prospective study we evaluate the utility of ATP in bacteriological surveillance, and the effects of endoscopy staff education and dual cycles of cleaning and high-level disinfection (HLD) on endoscope reprocessing. Methods ATP bioluminescence was measured after pre-cleaning, manual cleaning and HLD on rinsates from suction-biopsy channels of all endoscopes and elevator channels of duodenoscopes/linear echoendoscopes after use. ATP bioluminescence was re-measured in duodenoscopes (1) after re-education and competency testing of endoscopy staff, and subsequently (2) after 2 cycles of pre-cleaning and manual cleaning and single cycle of HLD, or (3) after 2 cycles of pre-cleaning, manual cleaning and HLD. Results The ideal ATP bioluminescence benchmark of <200 relative light units (RLUs) after manual cleaning was achieved from suction-biopsy channel rinsates of all endoscopes, but 9 of 10 duodenoscope elevator channel rinsates failed to meet this benchmark. Re-education reduced RLUs in duodenoscope elevator channel rinsates after pre-cleaning (23218.0 vs 1340.5 RLUs, p<0.01) and HLD (177.0 vs 12.0 RLUs, p<0.01). After 2 cycles of manual cleaning/HLD, duodenoscope elevator channel RLUs achieved levels similar to sterile water, with corresponding negative cultures. Conclusions ATP testing offers a rapid, inexpensive alternative for detection of endoscope microbial residue. Re-education of endoscopy staff and 2 cycles of cleaning and HLD decrease elevator channel RLUs to levels similar to sterile water and may therefore minimize the risk of transmission of infections by duodenoscopes. PMID:27818222

Sall1 Maintains Nephron Progenitors and Nascent Nephrons by Acting as Both an Activator and a Repressor

PubMed Central

Kanda, Shoichiro; Tanigawa, Shunsuke; Ohmori, Tomoko; Taguchi, Atsuhiro; Kudo, Kuniko; Suzuki, Yutaka; Sato, Yuki; Hino, Shinjiro; Sander, Maike; Perantoni, Alan O.; Sugano, Sumio; Nakao, Mitsuyoshi

2014-01-01

The balanced self-renewal and differentiation of nephron progenitors are critical for kidney development and controlled, in part, by the transcription factor Six2, which antagonizes canonical Wnt signaling-mediated differentiation. A nuclear factor, Sall1, is expressed in Six2-positive progenitors as well as differentiating nascent nephrons, and it is essential for kidney formation. However, the molecular functions and targets of Sall1, especially the functions and targets in the nephron progenitors, remain unknown. Here, we report that Sall1 deletion in Six2-positive nephron progenitors results in severe progenitor depletion and apoptosis of the differentiating nephrons in mice. Analysis of mice with an inducible Sall1 deletion revealed that Sall1 activates genes expressed in progenitors while repressing genes expressed in differentiating nephrons. Sall1 and Six2 co-occupied many progenitor-related gene loci, and Sall1 bound to Six2 biochemically. In contrast, Sall1 did not bind to the Wnt4 locus suppressed by Six2. Sall1-mediated repression was also independent of its binding to DNA. Thus, Sall1 maintains nephron progenitors and their derivatives by a unique mechanism, which partly overlaps but is distinct from that of Six2: Sall1 activates progenitor-related genes in Six2-positive nephron progenitors and represses gene expression in Six2-negative differentiating nascent nephrons. PMID:24744442

Simultaneous observation of nascent plasma and bubble induced by laser ablation in water with various pulse durations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tamura, Ayaka, E-mail: atamura@hiroshima-u.ac.jp; Matsumoto, Ayumu; Nishi, Naoya

2015-05-07

We investigate the effects of pulse duration on the dynamics of the nascent plasma and bubble induced by laser ablation in water. To examine the relationship between the nascent plasma and the bubble without disturbed by shot-to-shot fluctuation, we observe the images of the plasma and the bubble simultaneously by using two intensified charge coupled device detectors. We successfully observe the images of the plasma and bubble during the pulsed-irradiation, when the bubble size is as small as 20 μm. The light-emitting region of the plasma during the laser irradiation seems to exceed the bubble boundary in the case of themore » short-pulse (30-ns pulse) irradiation, while the size of the plasma is significantly smaller than that of the bubble in the case of the long-pulse (100-ns pulse) irradiation. The results suggest that the extent of the plasma quenching in the initial stage significantly depends on the pulse duration. Also, we investigate how the plasma-bubble relationship in the very early stage affects the shape of the atomic spectral lines observed at the later delay time of 600 ns. The present work gives important information to obtain high quality spectra in the application of underwater laser-induced breakdown spectroscopy, as well as to clarify the mechanism of liquid-phase laser ablation.« less

Hypomyelinating leukodystrophy-associated missense mutation in HSPD1 blunts mitochondrial dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miyamoto, Yuki; Eguchi, Takahiro; Kawahara, Kazuko

Myelin-forming glial cells undergo dynamic morphological changes in order to produce mature myelin sheaths with multiple layers. In the central nervous system (CNS), oligodendrocytes differentiate to insulate neuronal axons with myelin sheaths. Myelin sheaths play a key role in homeostasis of the nervous system, but their related disorders lead not only to dismyelination and repeated demyelination but also to severe neuropathies. Hereditary hypomyelinating leukodystrophies (HLDs) are a group of such diseases affecting oligodendrocytes and are often caused by missense mutations of the respective responsible genes. Despite increasing identification of gene mutations through advanced nucleotide sequencing technology, studies on the relationshipsmore » between gene mutations and their effects on cellular and subcellular aberrance have not followed at the same rapid pace. In this study, we report that an HLD4-associated (Asp-29-to-Gly) mutant of mitochondrial heat shock 60-kDa protein 1 (HSPD1) causes short-length morphologies and increases the numbers of mitochondria due to their aberrant fission and fusion cycles. In experiments using a fluorescent dye probe, this mutation decreases the mitochondrial membrane potential. Also, mitochondria accumulate in perinuclear regions. HLD4-associated HSPD1 mutant blunts mitochondrial dynamics, probably resulting in oligodendrocyte malfunction. This study constitutes a first finding concerning the relationship between disease-associated HSPD1 mutation and mitochondrial dynamics, which may be similar to the relationship between another disease-associated HSPD1 mutation (MitCHAP-60 disease) and aberrant mitochondrial dynamics. - Highlights: • The HLD4 mutant of HSPD1 decreases mitochondrial fission frequency. • The HLD4 mutant decreases mitochondrial fusion frequency. • Mitochondria harboring the HLD4 mutant exhibit slow motility. • The HLD4 mutant of HSPD1 decreases mitochondrial membrane potential. • HLD4-related

Adenosine triphosphate bioluminescence for bacteriologic surveillance and reprocessing strategies for minimizing risk of infection transmission by duodenoscopes.

PubMed

Sethi, Saurabh; Huang, Robert J; Barakat, Monique T; Banaei, Niaz; Friedland, Shai; Banerjee, Subhas

2017-06-01

Recent outbreaks of duodenoscope-transmitted infections underscore the importance of adequate endoscope reprocessing. Adenosine triphosphate (ATP) bioluminescence testing allows rapid evaluation of endoscopes for bacteriologic/biologic residue. In this prospective study we evaluate the utility of ATP in bacteriologic surveillance and the effects of endoscopy staff education and dual cycles of cleaning and high-level disinfection (HLD) on endoscope reprocessing. ATP bioluminescence was measured after precleaning, manual cleaning, and HLD on rinsates from suction-biopsy channels of all endoscopes and elevator channels of duodenoscopes/linear echoendoscopes after use. ATP bioluminescence was remeasured in duodenoscopes (1) after re-education and competency testing of endoscopy staff and subsequently (2) after 2 cycles of precleaning and manual cleaning and single cycle of HLD or (3) after 2 cycles of precleaning, manual cleaning, and HLD. The ideal ATP bioluminescence benchmark of <200 relative light units (RLUs) after manual cleaning was achieved from suction-biopsy channel rinsates of all endoscopes, but 9 of 10 duodenoscope elevator channel rinsates failed to meet this benchmark. Re-education reduced RLUs in duodenoscope elevator channel rinsates after precleaning (23,218.0 vs 1340.5 RLUs, P < .01) and HLD (177.0 vs 12.0 RLUs, P < .01). After 2 cycles of manual cleaning/HLD, duodenoscope elevator channel RLUs achieved levels similar to sterile water, with corresponding negative cultures. ATP testing offers a rapid, inexpensive alternative for detection of endoscope microbial residue. Re-education of endoscopy staff and 2 cycles of cleaning and HLD decreased elevator channel RLUs to levels similar to sterile water and may therefore minimize the risk of transmission of infections by duodenoscopes. Copyright © 2017 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

A two-way street: regulatory interplay between RNA polymerase and nascent RNA structure

PubMed Central

Zhang, Jinwei; Landick, Robert

2016-01-01

The vectorial (5′-to-3′ at varying velocity) synthesis of RNA by cellular RNA polymerases creates a rugged kinetic landscape, demarcated by frequent, sometimes long-lived pauses. In addition to myriad gene-regulatory roles, these pauses temporally and spatially program the co-transcriptional, hierarchical folding of biologically active RNAs. Conversely, these RNA structures, which form inside or near the RNA exit channel, interact with the polymerase and adjacent protein factors to influence RNA synthesis by modulating pausing, termination, antitermination, and slippage. Here we review the evolutionary origin, mechanistic underpinnings, and regulatory consequences of this interplay between RNA polymerase and nascent RNA structure. We categorize and attempt to rationalize the extensive linkage between the transcriptional machinery and its product, and provide a framework for future studies. PMID:26822487

A Two-Way Street: Regulatory Interplay between RNA Polymerase and Nascent RNA Structure.

PubMed

Zhang, Jinwei; Landick, Robert

2016-04-01

The vectorial (5'-to-3' at varying velocity) synthesis of RNA by cellular RNA polymerases (RNAPs) creates a rugged kinetic landscape, demarcated by frequent, sometimes long-lived, pauses. In addition to myriad gene-regulatory roles, these pauses temporally and spatially program the co-transcriptional, hierarchical folding of biologically active RNAs. Conversely, these RNA structures, which form inside or near the RNA exit channel, interact with the polymerase and adjacent protein factors to influence RNA synthesis by modulating pausing, termination, antitermination, and slippage. Here, we review the evolutionary origin, mechanistic underpinnings, and regulatory consequences of this interplay between RNAP and nascent RNA structure. We categorize and rationalize the extensive linkage between the transcriptional machinery and its product, and provide a framework for future studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Alterations in protein and amino acid metabolism in rats fed a branched-chain amino acid- or leucine-enriched diet during postprandial and postabsorptive states.

PubMed

Holecek, Milan; Siman, Pavel; Vodenicarovova, Melita; Kandar, Roman

2016-01-01

Many people believe in favourable effects of branched-chain amino acids (BCAAs; valine, leucine, and isoleucine), especially leucine, on muscle protein balance and consume BCAAs for many years. We determined the effects of the chronic intake of a BCAA- or leucine-enriched diet on protein and amino acid metabolism in fed and postabsorptive states. Rats were fed a standard diet, a diet with a high content of valine, leucine, and isoleucine (HVLID), or a high content of leucine (HLD) for 2 months. Half of the animals in each group were sacrificed in the fed state on the last day, and the other half were sacrificed after overnight fast. Protein synthesis was assessed using the flooding dose method (L-[3,4,5-(3)H]phenylalanine), proteolysis on the basis of chymotrypsin-like activity (CHTLA) of proteasome and cathepsin B and L activities. Chronic intake of HVLID or HLD enhanced plasma levels of urea, alanine and glutamine. HVLID also increased levels of all three BCAA and branched-chain keto acids (BCKA), HLD increased leucine, ketoisocaproate and alanine aminotransferase and decreased valine, ketovaline, isoleucine, ketoisoleucine, and LDL cholesterol. Tissue weight and protein content were lower in extensor digitorum longus muscles in the HLD group and higher in kidneys in the HVLID and HLD groups. Muscle protein synthesis in postprandial state was higher in the HVLID group, and CHTLA was lower in muscles of the HVLID and HLD groups compared to controls. Overnight starvation enhanced alanine aminotransferase activity in muscles, and decreased protein synthesis in gastrocnemius (in HVLID group) and extensor digitorum longus (in HLD group) muscles more than in controls. Effect of HVLID and HLD on CHTLA in muscles in postabsorptive state was insignificant. The results failed to demonstrate positive effects of the chronic consumption of a BCAA-enriched diet on protein balance in skeletal muscle and indicate rather negative effects from a leucine-enriched diet. The primary

Critical 23S rRNA interactions for macrolide-dependent ribosome stalling on the ErmCL nascent peptide chain

PubMed Central

Koch, Miriam; Willi, Jessica; Pradère, Ugo; Hall, Jonathan

2017-01-01

Abstract The nascent peptide exit tunnel has recently been identified as a functional region of ribosomes contributing to translation regulation and co-translational protein folding. Inducible expression of the erm resistance genes depends on ribosome stalling at specific codons of an upstream open reading frame in the presence of an exit tunnel-bound macrolide antibiotic. The molecular basis for this translation arrest is still not fully understood. Here, we used a nucleotide analog interference approach to unravel important functional groups on 23S rRNA residues in the ribosomal exit tunnel for ribosome stalling on the ErmC leader peptide. By replacing single nucleobase functional groups or even single atoms we were able to demonstrate the importance of A2062, A2503 and U2586 for drug-dependent ribosome stalling. Our data show that the universally conserved A2062 and A2503 are capable of forming a non-Watson–Crick base pair that is critical for sensing and transmitting the stalling signal from the exit tunnel back to the peptidyl transferase center of the ribosome. The nucleobases of A2062, A2503 as well as U2586 do not contribute significantly to the overall mechanism of protein biosynthesis, yet their elaborate role for co-translational monitoring of nascent peptide chains inside the exit tunnel can explain their evolutionary conservation. PMID:28369621

Selective stalling of human translation through small-molecule engagement of the ribosome nascent chain

PubMed Central

Lintner, Nathanael G.; McClure, Kim F.; Petersen, Donna; Londregan, Allyn T.; Piotrowski, David W.; Wei, Liuqing; Xiao, Jun; Bolt, Michael; Loria, Paula M.; Maguire, Bruce; Geoghegan, Kieran F.; Huang, Austin; Rolph, Tim; Liras, Spiros; Doudna, Jennifer A.; Dullea, Robert G.

2017-01-01

Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a key role in regulating the levels of plasma low-density lipoprotein cholesterol (LDL-C). Here, we demonstrate that the compound PF-06446846 inhibits translation of PCSK9 by inducing the ribosome to stall around codon 34, mediated by the sequence of the nascent chain within the exit tunnel. We further show that PF-06446846 reduces plasma PCSK9 and total cholesterol levels in rats following oral dosing. Using ribosome profiling, we demonstrate that PF-06446846 is highly selective for the inhibition of PCSK9 translation. The mechanism of action employed by PF-06446846 reveals a previously unexpected tunability of the human ribosome that allows small molecules to specifically block translation of individual transcripts. PMID:28323820

Long-term effects of grazing and topography on extra-radical hyphae of arbuscular mycorrhizal fungi in semi-arid grasslands.

PubMed

Ren, Haiyan; Gui, Weiyang; Bai, Yongfei; Stein, Claudia; Rodrigues, Jorge L M; Wilson, Gail W T; Cobb, Adam B; Zhang, Yingjun; Yang, Gaowen

2018-02-01

Grazing and topography have drastic effects on plant communities and soil properties. These effects are thought to influence arbuscular mycorrhizal (AM) fungi. However, the simultaneous impacts of grazing pressure (sheep ha -1 ) and topography on plant and soil factors and their relationship to the production of extra-radical AM hyphae are not well understood. Our 10-year study assessed relationships between grazing, plant species richness, aboveground plant productivity, soil nutrients, edaphic properties, and AM hyphal length density (HLD) in different topographic areas (flat or sloped). We found HLD linearly declined with increasing grazing pressure (1.5-9.0 sheep ha -1 ) in sloped areas, but HLD was greatest at moderate grazing pressure (4.5 sheep ha -1 ) in flat areas. Structural equation modeling indicates grazing reduces HLD by altering soil nutrient dynamics in sloped areas, but non-linearly influences HLD through plant community and edaphic changes in flat areas. Our findings highlight how topography influences key plant and soil factors, thus regulating the effects of grazing pressure on extra-radical hyphal production of AM fungi in grasslands. Understanding how grazing and topography influence AM fungi in semi-arid grasslands is vital, as globally, severe human population pressure and increasing demand for food aggravate the grazing intensity in grasslands.

Co-translational capturing of nascent ribosomal proteins by their dedicated chaperones

PubMed Central

Pausch, Patrick; Singh, Ujjwala; Ahmed, Yasar Luqman; Pillet, Benjamin; Murat, Guillaume; Altegoer, Florian; Stier, Gunter; Thoms, Matthias; Hurt, Ed; Sinning, Irmgard; Bange, Gert; Kressler, Dieter

2015-01-01

Exponentially growing yeast cells produce every minute >160,000 ribosomal proteins. Owing to their difficult physicochemical properties, the synthesis of assembly-competent ribosomal proteins represents a major challenge. Recent evidence highlights that dedicated chaperone proteins recognize the N-terminal regions of ribosomal proteins and promote their soluble expression and delivery to the assembly site. Here we explore the intuitive possibility that ribosomal proteins are captured by dedicated chaperones in a co-translational manner. Affinity purification of four chaperones (Rrb1, Syo1, Sqt1 and Yar1) selectively enriched the mRNAs encoding their specific ribosomal protein clients (Rpl3, Rpl5, Rpl10 and Rps3). X-ray crystallography reveals how the N-terminal, rRNA-binding residues of Rpl10 are shielded by Sqt1's WD-repeat β-propeller, providing mechanistic insight into the incorporation of Rpl10 into pre-60S subunits. Co-translational capturing of nascent ribosomal proteins by dedicated chaperones constitutes an elegant mechanism to prevent unspecific interactions and aggregation of ribosomal proteins on their road to incorporation. PMID:26112308

Tail-extension following the termination codon is critical for release of the nascent chain from membrane-bound ribosomes in a reticulocyte lysate cell-free system.

PubMed

Takahara, Michiyo; Sakaue, Haruka; Onishi, Yukiko; Yamagishi, Marifu; Kida, Yuichiro; Sakaguchi, Masao

2013-01-11

Nascent chain release from membrane-bound ribosomes by the termination codon was investigated using a cell-free translation system from rabbit supplemented with rough microsomal membrane vesicles. Chain release was extremely slow when mRNA ended with only the termination codon. Tail extension after the termination codon enhanced the release of the nascent chain. Release reached plateau levels with tail extension of 10 bases. This requirement was observed with all termination codons: TAA, TGA and TAG. Rapid release was also achieved by puromycin even in the absence of the extension. Efficient translation termination cannot be achieved in the presence of only a termination codon on the mRNA. Tail extension might be required for correct positioning of the termination codon in the ribosome and/or efficient recognition by release factors. Copyright © 2012. Published by Elsevier Inc.

Toxicological investigations on the methanol sub-fraction of the seeds of Carica papaya as a male contraceptive in albino rats.

PubMed

Lohiya, Nirmal K; Manivannan, Boomi; Garg, Shipra

2006-10-01

Pre-clinical acute and sub-chronic toxicity studies of the methanol sub-fraction (MSF) of the seeds of Carica papaya, a putative male contraceptive, have been investigated in rats to evaluate safety of the test substance. A single oral dose of MSF at 2000 mg/kg body weight was studied over 14 days for acute toxicity, and daily oral doses of 50, 100, 250 and 500 mg/kg body weight were studied for 28- and 90-day periods for sub-chronic toxicity. Body weight, food and water intake and phenotypical toxicological symptoms were recorded daily. Sperm analysis, hematology, serum clinical biochemistry, libido and pathological examination of vital organs were recorded at the termination of the experimental periods. We observed no overt general toxicity in exposed animals. Food and water intake showed daily fluctuations within control limits. Sperm density showed a significant decrease in all 28- and 90-day repeated dose treated animals whereas total sperm motility inhibition was observed at 250 and 500 mg/kg dose levels at the 28-day time interval but in all dose groups at the 90-day interval. The preliminary results suggest the test substance may be a safe approach to male anti-fertility.

Autosomal InDel polymorphisms for population genetic structure and differentiation analysis of Chinese Kazak ethnic group

PubMed Central

Kong, Tingting; Chen, Yahao; Guo, Yuxin; Wei, Yuanyuan; Jin, Xiaoye; Xie, Tong; Mu, Yuling; Dong, Qian; Wen, Shaoqing; Zhou, Boyan; Zhang, Li; Shen, Chunmei; Zhu, Bofeng

2017-01-01

In the present study, we assessed the genetic diversities of the Chinese Kazak ethnic group on the basis of 30 well-chosen autosomal insertion and deletion loci and explored the genetic relationships between Kazak and 23 reference groups. We detected the level of the expected heterozygosity ranging from 0.3605 at HLD39 locus to 0.5000 at HLD136 locus and the observed heterozygosity ranging from 0.3548 at HLD39 locus to 0.5283 at HLD136 locus. The combined power of discrimination and the combined power of exclusion for all 30 loci in the studied Kazak group were 0.999999999999128 and 0.9945, respectively. The dataset generated in this study indicated the panel of 30 InDels was highly efficient in forensic individual identifcation but may not have enough power in paternity cases. The results of the interpopulation differentiations, PCA plots, phylogenetic trees and STRUCTURE analyses showed a close genetic affiliation between the Kazak and Uigur group. PMID:28915619

Selective ribosome profiling as a tool to study the interaction of chaperones and targeting factors with nascent polypeptide chains and ribosomes

PubMed Central

Becker, Annemarie H.; Oh, Eugene; Weissman, Jonathan S.; Kramer, Günter; Bukau, Bernd

2014-01-01

A plethora of factors is involved in the maturation of newly synthesized proteins, including chaperones, membrane targeting factors, and enzymes. Many factors act cotranslationally through association with ribosome-nascent chain complexes (RNCs), but their target specificities and modes of action remain poorly understood. We developed selective ribosome profiling (SeRP) to identify substrate pools and points of RNC engagement of these factors. SeRP is based on sequencing mRNA fragments covered by translating ribosomes (general ribosome profiling, RP), combined with a procedure to selectively isolate RNCs whose nascent polypeptides are associated with the factor of interest. Factor–RNC interactions are stabilized by crosslinking, the resulting factor–RNC adducts are then nuclease-treated to generate monosomes, and affinity-purified. The ribosome-extracted mRNA footprints are converted to DNA libraries for deep sequencing. The protocol is specified for general RP and SeRP in bacteria. It was first applied to the chaperone trigger factor and is readily adaptable to other cotranslationally acting factors, including eukaryotic factors. Factor–RNC purification and sequencing library preparation takes 7–8 days, sequencing and data analysis can be completed in 5–6 days. PMID:24136347

Induction of natural competence in Streptococcus pneumoniae triggers lysis and DNA release from a subfraction of the cell population.

PubMed

Steinmoen, Hilde; Knutsen, Eivind; Håvarstein, Leiv Sigve

2002-05-28

Naturally competent bacteria have the ability to take up free DNA from the surrounding medium and incorporate this DNA into their genomes by homologous recombination. In naturally competent Streptococcus pneumoniae, and related streptococcal species from the mitis phylogenetic group, the competent state is not a constitutive property but is induced by a peptide pheromone through a quorum-sensing mechanism. Recent studies have shown that natural genetic transformation is an important mechanism for gene exchange between streptococci in nature. A prerequisite for effective gene exchange is the presence of streptococcal donor DNA in the environment. Despite decades of study of the transformation process we still do not know how this donor DNA is released from streptococcal cells to the external milieu. Traditionally, it has been assumed that donor DNA originates from cells that die and fall apart from natural causes. In this study we show that induction of the competent state initiates release of DNA from a subfraction of the bacterial population, probably by cell lysis. The majority of the cells induced to competence take up DNA and act as recipients, whereas the rest release DNA and act as donors. These findings show that natural transformation in streptococci provides a natural mechanism for genetic recombination that resembles sex in higher organisms.

Determination of hemispheric language dominance using functional magnetic resonance imaging and the Shiritori (Japanese word chain) task in patients with epilepsy: Comparison with the Wada test.

PubMed

Kashida, Yumi; Otsubo, Toshiaki; Hanaya, Ryosuke; Kodabashi, Atsushi; Tsumagari, Noriko; Sugata, Sei; Hosoyama, Hiroshi; Iida, Koji; Nakamura, Katsumi; Tokimura, Hiroshi; Fujimoto, Toshiro; Arita, Kazunori

2016-08-01

The Wada test has been the gold standard for determining hemispheric language dominance (HLD) in the presurgical evaluation of patients scheduled for neurosurgical procedures. As it poses inherent risks associated with intra-arterial catheter techniques and as it occasionally fails to indicate language dominance, an alternative reliable test is needed. We quantitatively assessed the results of functional magnetic resonance imaging (fMRI) using the Shiritori task, a Japanese word chain, to identify the threshold for correctly predicting HLD. The subjects were 28 patients with intractable epilepsy scheduled to undergo the Wada test and focus resection. We set the region of interest (ROI) on the bilateral Brodmann areas 44 and 45 (BA 44 and 45). To compare the functional activity at both ROIs we calculated the language laterality index (LI) using the formula: [VL-VR]/[VL+VR]×100, where VL and VR indicated the number of activated voxels in the left and right ROIs, respectively. As 2 patients were excluded due to the lack of activation in either ROI, the final study population consisted of 26 patients. By the Wada test, HLD was left in 20, right in 3, and equivocal in 3. At a cut-off of LI+50, the predictive sensitivity and specificity for left HLD were 85% (17/20) and 100%; right HLD was predicted in a single patient (sensitivity 33.3%, specificity 100%). The fMRI using the Shiritori task showed good activation in ROI of BA 44 and 45. At a cut-off of LI+50, LI of BA 44 and 45 predicted HLD identified by the Wada test with high specificity. Copyright © 2016 Elsevier B.V. All rights reserved.

Critical 23S rRNA interactions for macrolide-dependent ribosome stalling on the ErmCL nascent peptide chain.

PubMed

Koch, Miriam; Willi, Jessica; Pradère, Ugo; Hall, Jonathan; Polacek, Norbert

2017-06-20

The nascent peptide exit tunnel has recently been identified as a functional region of ribosomes contributing to translation regulation and co-translational protein folding. Inducible expression of the erm resistance genes depends on ribosome stalling at specific codons of an upstream open reading frame in the presence of an exit tunnel-bound macrolide antibiotic. The molecular basis for this translation arrest is still not fully understood. Here, we used a nucleotide analog interference approach to unravel important functional groups on 23S rRNA residues in the ribosomal exit tunnel for ribosome stalling on the ErmC leader peptide. By replacing single nucleobase functional groups or even single atoms we were able to demonstrate the importance of A2062, A2503 and U2586 for drug-dependent ribosome stalling. Our data show that the universally conserved A2062 and A2503 are capable of forming a non-Watson-Crick base pair that is critical for sensing and transmitting the stalling signal from the exit tunnel back to the peptidyl transferase center of the ribosome. The nucleobases of A2062, A2503 as well as U2586 do not contribute significantly to the overall mechanism of protein biosynthesis, yet their elaborate role for co-translational monitoring of nascent peptide chains inside the exit tunnel can explain their evolutionary conservation. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Photoionization mass spectrometry for the investigation of combustion generated nascent nanoparticles and their relation to laser induced incandescence

NASA Astrophysics Data System (ADS)

Grotheer, H.-H.; Wolf, K.; Hoffmann, K.

2011-08-01

Premixed laminar flat ethylene flames were investigated for nascent nanoparticles through photoionization mass spectrometry (PIMS). Using an atmospheric McKenna burner and ethylene air flames coupled to an atmospheric sampling system, within a relatively narrow C/O range two modes of these particles were found, which can be clearly distinguished with regard to their temperature dependence, their reactivity, and their ionization behaviour. Behind a diesel engine the same particles were observed. These results were corroborated using a low pressure ethylene-O2 flame coupled to a high resolution mass spectrometer. In this case, due to a special inlet system, it was possible to operate the flame in a fairly wide C/O range without clogging of the inlet nozzles. This allowed pursuing the development of particle size distribution functions (PSDF) well into the regime of mature soot. In addition, on the low mass side of the particle spectra measurements with unity resolution were possible and this allowed gaining information concerning their growth mechanism and structure. Finally, in an attempt to mimic Laser Induced Incandescence (LII) experiments the soot-laden molecular beam was exposed to IR irradiation. This resulted in a near complete destruction of nascent particles under LII typical fluences. Small C clusters between 3 and 17 C atoms were found. In addition and with much higher intensities, clusters comprising several hundreds of C atoms were also detected, the latter even at very low fluences when small clusters were totally absent.

Nascent Transcription Affected by RNA Polymerase IV in Zea mays

PubMed Central

Erhard, Karl F.; Talbot, Joy-El R. B.; Deans, Natalie C.; McClish, Allison E.; Hollick, Jay B.

2015-01-01

All eukaryotes use three DNA-dependent RNA polymerases (RNAPs) to create cellular RNAs from DNA templates. Plants have additional RNAPs related to Pol II, but their evolutionary role(s) remain largely unknown. Zea mays (maize) RNA polymerase D1 (RPD1), the largest subunit of RNA polymerase IV (Pol IV), is required for normal plant development, paramutation, transcriptional repression of certain transposable elements (TEs), and transcriptional regulation of specific alleles. Here, we define the nascent transcriptomes of rpd1 mutant and wild-type (WT) seedlings using global run-on sequencing (GRO-seq) to identify the broader targets of RPD1-based regulation. Comparisons of WT and rpd1 mutant GRO-seq profiles indicate that Pol IV globally affects transcription at both transcriptional start sites and immediately downstream of polyadenylation addition sites. We found no evidence of divergent transcription from gene promoters as seen in mammalian GRO-seq profiles. Statistical comparisons identify genes and TEs whose transcription is affected by RPD1. Most examples of significant increases in genic antisense transcription appear to be initiated by 3ʹ-proximal long terminal repeat retrotransposons. These results indicate that maize Pol IV specifies Pol II-based transcriptional regulation for specific regions of the maize genome including genes having developmental significance. PMID:25653306

RNA editing in nascent RNA affects pre-mRNA splicing

PubMed Central

Hsiao, Yun-Hua Esther; Bahn, Jae Hoon; Yang, Yun; Lin, Xianzhi; Tran, Stephen; Yang, Ei-Wen; Quinones-Valdez, Giovanni

2018-01-01

In eukaryotes, nascent RNA transcripts undergo an intricate series of RNA processing steps to achieve mRNA maturation. RNA editing and alternative splicing are two major RNA processing steps that can introduce significant modifications to the final gene products. By tackling these processes in isolation, recent studies have enabled substantial progress in understanding their global RNA targets and regulatory pathways. However, the interplay between individual steps of RNA processing, an essential aspect of gene regulation, remains poorly understood. By sequencing the RNA of different subcellular fractions, we examined the timing of adenosine-to-inosine (A-to-I) RNA editing and its impact on alternative splicing. We observed that >95% A-to-I RNA editing events occurred in the chromatin-associated RNA prior to polyadenylation. We report about 500 editing sites in the 3′ acceptor sequences that can alter splicing of the associated exons. These exons are highly conserved during evolution and reside in genes with important cellular function. Furthermore, we identified a second class of exons whose splicing is likely modulated by RNA secondary structures that are recognized by the RNA editing machinery. The genome-wide analyses, supported by experimental validations, revealed remarkable interplay between RNA editing and splicing and expanded the repertoire of functional RNA editing sites. PMID:29724793

Reading Does Not Depend on Writing, Even in Chinese

ERIC Educational Resources Information Center

Bi, Yanchao; Han, Zaizhu; Zhang, Yumei

2009-01-01

A recent hypothesis proposes that reading depends on writing in a logographic language--Chinese. We present a Chinese individual (HLD) with brain damage whose profile challenges this hypothesis. HLD was severely impaired in the whole process of writing. He could not access orthographic knowledge, had poor orthographic awareness, and was poor at…

Structural Basis for Recognition and Sequestration of UUUOH 3 ' Temini of Nascent RNA Polymerase III Transcripts by La, a Rheumatic Disease Autoantigen

DOE Office of Scientific and Technical Information (OSTI.GOV)

Teplova,M.; Yuan, Y.; Phan, A.

2006-01-01

The nuclear phosphoprotein La was identified as an autoantigen in patients with systemic lupus erythematosus and Sjogren's syndrome. La binds to and protects the UUUOH 3' terminii of nascent RNA polymerase III transcripts from exonuclease digestion. We report the 1.85 Angstroms crystal structure of the N-terminal domain of human La, consisting of La and RRM1 motifs, bound to r(U1-G2-C3-U4-G5-U6-U7-U8-U9OH). The U7-U8-U9OH 3' end, in a splayed-apart orientation, is sequestered within a basic and aromatic amino acid-lined cleft between the La and RRM1 motifs. The specificity-determining U8 residue bridges both motifs, in part through unprecedented targeting of the {beta} sheet edge,more » rather than the anticipated face, of the RRM1 motif. Our structural observations, supported by mutation studies of both La and RNA components, illustrate the principles behind RNA sequestration by a rheumatic disease autoantigen, whereby the UUUOH 3' ends of nascent RNA transcripts are protected during downstream processing and maturation events.« less

Characterizing and controlling intrinsic biases of lambda exonuclease in nascent strand sequencing reveals phasing between nucleosomes and G-quadruplex motifs around a subset of human replication origins

PubMed Central

Foulk, Michael S.; Urban, John M.; Casella, Cinzia; Gerbi, Susan A.

2015-01-01

Nascent strand sequencing (NS-seq) is used to discover DNA replication origins genome-wide, allowing identification of features for their specification. NS-seq depends on the ability of lambda exonuclease (λ-exo) to efficiently digest parental DNA while leaving RNA-primer protected nascent strands intact. We used genomics and biochemical approaches to determine if λ-exo digests all parental DNA sequences equally. We report that λ-exo does not efficiently digest G-quadruplex (G4) structures in a plasmid. Moreover, λ-exo digestion of nonreplicating genomic DNA (LexoG0) enriches GC-rich DNA and G4 motifs genome-wide. We used LexoG0 data to control for nascent strand–independent λ-exo biases in NS-seq and validated this approach at the rDNA locus. The λ-exo–controlled NS-seq peaks are not GC-rich, and only 35.5% overlap with 6.8% of all G4s, suggesting that G4s are not general determinants for origin specification but may play a role for a subset. Interestingly, we observed a periodic spacing of G4 motifs and nucleosomes around the peak summits, suggesting that G4s may position nucleosomes at this subset of origins. Finally, we demonstrate that use of Na+ instead of K+ in the λ-exo digestion buffer reduced the effect of G4s on λ-exo digestion and discuss ways to increase both the sensitivity and specificity of NS-seq. PMID:25695952

Population Differentiations and Phylogenetic Analysis of Tibet and Qinghai Tibetan Groups Based on 30 InDel Loci.

PubMed

Guo, Yuxin; Shen, Chunmei; Meng, Haotian; Dong, Qian; Kong, Tingting; Yang, Chunhua; Wang, Hongdan; Jin, Rui; Zhu, Bofeng

2016-12-01

In recent years, Insertion/Deletion (InDel) polymorphisms have become a hot area of forensic research. In this study, 30 InDel loci were selected to investigate the genetic polymorphisms of Tibetan groups, which are from Tibet Autonomous Region and Qinghai province of China, and explore the genetic relationships between Tibetan groups and other groups. Allele frequencies of the 30 InDel loci ranged from 0.1219 (HLD111) to 0.5609 (HLD57) in the Tibet Tibetan group and 0.1639 (HLD118) to 0.5655 (HLD124) in the Qinghai Tibetan group. The combined power of discrimination, matching probability, and power of exclusion were 0.999999999986, 0.999999988, and 0.9913 in the Tibet Tibetan group, respectively, and 0.99999999999204, 0.9999999796, and 0.9862 in the Qinghai Tibetan group. The results of principal component analysis, phylogenetic tree, and population structure demonstrated that the four Tibetan groups (Tibetan1, Tibetan2, Tibet, and Qinghai Tibetan groups) clustered together and had relatively close genetic relationships with nine Asian groups and then European and Amerindian groups.

Forensic evaluation and population genetic study of 30 insertion/deletion polymorphisms in a Chinese Yi group.

PubMed

Zhang, Yu-Dang; Shen, Chun-Mei; Jin, Rui; Li, Ya-Ni; Wang, Bo; Ma, Li-Xia; Meng, Hao-Tian; Yan, Jiang-Wei; Dan Wang, Hong-; Yang, Ze-Long; Zhu, Bo-Feng

2015-05-01

Insertion/deletion polymorphisms have become a research hot spot in forensic science due to their tremendous potential in recent years. In the present study, we investigated 30 indel loci in a Chinese Yi ethnic group. The allele frequencies of the short allele of the 30 indel loci were in the range of 0.1025-0.9221. The power of discrimination values were observed ranging from to 0.2630 (HLD111 locus) to 0.6607 (HLD70 locus) and probability of exclusion values ranged from 0.0189 (HLD111 locus) to 0.2343 (HLD56 locus). The combined power of discrimination and power of exclusion for 30 loci in the studied Yi group were 0.99999999995713 and 0.97746, respectively, which showed tremendous potential for forensic personal identification in the Yi group. Moreover, the DA distances, phylogenetic tree, principal component analysis, and cluster analysis showed the Yi group had close genetic relationships with the Tibetan, South Korean, Chinese Han, and She groups. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

RNA editing in nascent RNA affects pre-mRNA splicing.

PubMed

Hsiao, Yun-Hua Esther; Bahn, Jae Hoon; Yang, Yun; Lin, Xianzhi; Tran, Stephen; Yang, Ei-Wen; Quinones-Valdez, Giovanni; Xiao, Xinshu

2018-06-01

In eukaryotes, nascent RNA transcripts undergo an intricate series of RNA processing steps to achieve mRNA maturation. RNA editing and alternative splicing are two major RNA processing steps that can introduce significant modifications to the final gene products. By tackling these processes in isolation, recent studies have enabled substantial progress in understanding their global RNA targets and regulatory pathways. However, the interplay between individual steps of RNA processing, an essential aspect of gene regulation, remains poorly understood. By sequencing the RNA of different subcellular fractions, we examined the timing of adenosine-to-inosine (A-to-I) RNA editing and its impact on alternative splicing. We observed that >95% A-to-I RNA editing events occurred in the chromatin-associated RNA prior to polyadenylation. We report about 500 editing sites in the 3' acceptor sequences that can alter splicing of the associated exons. These exons are highly conserved during evolution and reside in genes with important cellular function. Furthermore, we identified a second class of exons whose splicing is likely modulated by RNA secondary structures that are recognized by the RNA editing machinery. The genome-wide analyses, supported by experimental validations, revealed remarkable interplay between RNA editing and splicing and expanded the repertoire of functional RNA editing sites. © 2018 Hsiao et al.; Published by Cold Spring Harbor Laboratory Press.

A study on a nascent entomopathogenic association between caenorhabditis briggsae and serratia sp.SCBI

NASA Astrophysics Data System (ADS)

Abebe-Akele, Feseha

Life is inconceivable in the absence of interactions which could be cooperative, antagonistic or neutral. Interactions are in constant flux because on one hand it is often difficult to demarcate where one form of interaction ends and the other begins on the other hand what is cooperative at one point in time could evolve into antagonistic or neutral or vice versa. Thus, organisms, as a consequence of mutation, adaptation and natural selection would inevitably enter into natural associations from which they emerge as mutual partners, inveterate enemies or passive cohabitants. Entomopathogenic nematode (EPN) partnerships are tripartite interactions where a nematode-bacteria symbiont duo attacks a third organism -an insect or insect larva-for the mutual benefit of the attacking partners and the detriment of the insect they invade. All three participants in the interaction---the nematode worms with their symbiont bacteria and the target insect host-are among the most ancient, diverse and abundant species on earth, however, these EPN partnerships are not as common as circumstances would suggest. EPN associations, which are arguably at the peak of evolutionary co adaptations, where two primitive forms of life cooperate to take advantage of a larger species are not only fascinating but immensely important for humans. The biological and molecular mechanisms underlying entomopathogenesis have been studied in great detail for decades for their potential as biological control agents against invasive insects. In spite of intense research in The EPN field, the evolutionary history of EPN associations are largely unknown because there are no known intermediate forms. In this thesis, a nascent EPN partnership is described between Caenorhabditid nematodes and Serratia sp. SCBI. Comparative analysis of this association with other EPNs suggests that crucial aspect of EPN associations may be the ability of partners to co-exist without killing each other and that the end results of

Structural basis for recognition and sequestration of UUU(OH) 3' temini of nascent RNA polymerase III transcripts by La, a rheumatic disease autoantigen.

PubMed

Teplova, Marianna; Yuan, Yu-Ren; Phan, Anh Tuân; Malinina, Lucy; Ilin, Serge; Teplov, Alexei; Patel, Dinshaw J

2006-01-06

The nuclear phosphoprotein La was identified as an autoantigen in patients with systemic lupus erythematosus and Sjogren's syndrome. La binds to and protects the UUU(OH) 3' terminii of nascent RNA polymerase III transcripts from exonuclease digestion. We report the 1.85 angstroms crystal structure of the N-terminal domain of human La, consisting of La and RRM1 motifs, bound to r(U1-G2-C3-U4-G5-U6-U7-U8-U9OH). The U7-U8-U9OH 3' end, in a splayed-apart orientation, is sequestered within a basic and aromatic amino acid-lined cleft between the La and RRM1 motifs. The specificity-determining U8 residue bridges both motifs, in part through unprecedented targeting of the beta sheet edge, rather than the anticipated face, of the RRM1 motif. Our structural observations, supported by mutation studies of both La and RNA components, illustrate the principles behind RNA sequestration by a rheumatic disease autoantigen, whereby the UUU(OH) 3' ends of nascent RNA transcripts are protected during downstream processing and maturation events.

Characterizing and controlling intrinsic biases of lambda exonuclease in nascent strand sequencing reveals phasing between nucleosomes and G-quadruplex motifs around a subset of human replication origins.

PubMed

Foulk, Michael S; Urban, John M; Casella, Cinzia; Gerbi, Susan A

2015-05-01

Nascent strand sequencing (NS-seq) is used to discover DNA replication origins genome-wide, allowing identification of features for their specification. NS-seq depends on the ability of lambda exonuclease (λ-exo) to efficiently digest parental DNA while leaving RNA-primer protected nascent strands intact. We used genomics and biochemical approaches to determine if λ-exo digests all parental DNA sequences equally. We report that λ-exo does not efficiently digest G-quadruplex (G4) structures in a plasmid. Moreover, λ-exo digestion of nonreplicating genomic DNA (LexoG0) enriches GC-rich DNA and G4 motifs genome-wide. We used LexoG0 data to control for nascent strand-independent λ-exo biases in NS-seq and validated this approach at the rDNA locus. The λ-exo-controlled NS-seq peaks are not GC-rich, and only 35.5% overlap with 6.8% of all G4s, suggesting that G4s are not general determinants for origin specification but may play a role for a subset. Interestingly, we observed a periodic spacing of G4 motifs and nucleosomes around the peak summits, suggesting that G4s may position nucleosomes at this subset of origins. Finally, we demonstrate that use of Na(+) instead of K(+) in the λ-exo digestion buffer reduced the effect of G4s on λ-exo digestion and discuss ways to increase both the sensitivity and specificity of NS-seq. © 2015 Foulk et al.; Published by Cold Spring Harbor Laboratory Press.

Multi-imaging analysis of nascent surface structures generated during femtosecond laser irradiation of silicon in high vacuum

NASA Astrophysics Data System (ADS)

Gesuele, F.; JJ Nivas, J.; Fittipaldi, R.; Altucci, C.; Bruzzese, R.; Maddalena, P.; Amoruso, S.

2018-02-01

We report a correlative imaging analysis of a crystalline silicon target after irradiation with a low number of 1055 nm, 850 fs laser pulses with several microscopy techniques (e.g., scanning electron microscopy, atomic force microscopy, Raman micro-imaging and confocal optical microscopy). The analysis is carried out on samples irradiated both in high vacuum and at atmospheric pressure conditions, evidencing interesting differences induced by the ambient environment. In high-vacuum conditions, the results evidence the formation of a halo, which is constituted by alternate stripes of amorphous and crystalline silicon, around the nascent ablation crater. In air, such an effect is drastically reduced, due to the significant back-deposition of nanoparticulate material induced by the larger ambient pressure.

Nascent life cycles and the emergence of higher-level individuality.

PubMed

Ratcliff, William C; Herron, Matthew; Conlin, Peter L; Libby, Eric

2017-12-05

Evolutionary transitions in individuality (ETIs) occur when formerly autonomous organisms evolve to become parts of a new, 'higher-level' organism. One of the first major hurdles that must be overcome during an ETI is the emergence of Darwinian evolvability in the higher-level entity (e.g. a multicellular group), and the loss of Darwinian autonomy in the lower-level units (e.g. individual cells). Here, we examine how simple higher-level life cycles are a key innovation during an ETI, allowing this transfer of fitness to occur 'for free'. Specifically, we show how novel life cycles can arise and lead to the origin of higher-level individuals by (i) mitigating conflicts between levels of selection, (ii) engendering the expression of heritable higher-level traits and (iii) allowing selection to efficiently act on these emergent higher-level traits. Further, we compute how canonical early life cycles vary in their ability to fix beneficial mutations via mathematical modelling. Life cycles that lack a persistent lower-level stage and develop clonally are far more likely to fix 'ratcheting' mutations that limit evolutionary reversion to the pre-ETI state. By stabilizing the fragile first steps of an evolutionary transition in individuality, nascent higher-level life cycles may play a crucial role in the origin of complex life.This article is part of the themed issue 'Process and pattern in innovations from cells to societies'. © 2017 The Author(s).

An allosteric Sec61 inhibitor traps nascent transmembrane helices at the lateral gate

PubMed Central

MacKinnon, Andrew L; Paavilainen, Ville O; Sharma, Ajay; Hegde, Ramanujan S; Taunton, Jack

2014-01-01

Membrane protein biogenesis requires the coordinated movement of hydrophobic transmembrane domains (TMD) from the cytosolic vestibule of the Sec61 channel into the lipid bilayer. Molecular insight into TMD integration has been hampered by the difficulty of characterizing intermediates during this intrinsically dynamic process. In this study, we show that cotransin, a substrate-selective Sec61 inhibitor, traps nascent TMDs in the cytosolic vestibule, permitting detailed interrogation of an early pre-integration intermediate. Site-specific crosslinking revealed the pre-integrated TMD docked to Sec61 near the cytosolic tip of the lateral gate. Escape from cotransin-arrest depends not only on cotransin concentration, but also on the biophysical properties of the TMD. Genetic selection of cotransin-resistant cancer cells uncovered multiple mutations clustered near the lumenal plug of Sec61α, thus revealing cotransin’s likely site of action. Our results suggest that TMD/lateral gate interactions facilitate TMD transfer into the membrane, a process that is allosterically modulated by cotransin binding to the plug. DOI: http://dx.doi.org/10.7554/eLife.01483.001 PMID:24497544

Identification of Nascent Memory CD8 T Cells and Modeling of Their Ontogeny.

PubMed

Crauste, Fabien; Mafille, Julien; Boucinha, Lilia; Djebali, Sophia; Gandrillon, Olivier; Marvel, Jacqueline; Arpin, Christophe

2017-03-22

Primary immune responses generate short-term effectors and long-term protective memory cells. The delineation of the genealogy linking naive, effector, and memory cells has been complicated by the lack of phenotypes discriminating effector from memory differentiation stages. Using transcriptomics and phenotypic analyses, we identify Bcl2 and Mki67 as a marker combination that enables the tracking of nascent memory cells within the effector phase. We then use a formal approach based on mathematical models describing the dynamics of population size evolution to test potential progeny links and demonstrate that most cells follow a linear naive→early effector→late effector→memory pathway. Moreover, our mathematical model allows long-term prediction of memory cell numbers from a few early experimental measurements. Our work thus provides a phenotypic means to identify effector and memory cells, as well as a mathematical framework to investigate their genealogy and to predict the outcome of immunization regimens in terms of memory cell numbers generated. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Nascent PO(X 2Π) E,V,R,T excitations from collision-free IR laser photolysis: Specificity toward the PO(X 2Pi 1/2) spin-orbit statea)

NASA Astrophysics Data System (ADS)

Chou, Jim-Son; Sumida, David S.; Wittig, C.

1985-02-01

PO (X 2Π) is produced via the collision-free infrared multiple photon dissociation (IRMPD) of volatile organophosphorous molecules, and is detected by two-frequency two-photon ionization, using the B 2Σ+ state to provide a spectral signature from which X 2Π populations are obtained. Sequential dissociations occur during the IR laser photolysis, in which nascent fragments continue to undergo IRMPD, and PO (X 2Π) accrues from a series of bond fission reactions. Nascent vibrational, rotational, and translational excitations are in sensible accord with this mechanism, except for a few rotational states near J=19.5. Unlike the nuclear degrees of freedom, the PO (X 2Π) spin-orbit states are populated quite selectively. The 2Π3/2 state, lying only 224 cm-1 above the 2Π1/2 ground state, contains only ˜11% of the population, compared to 34% for a 300 K sample. This result is unambiguous; it persists with all precursors, laser fluences, etc., and is verified by comparisons to spectra obtained using a microwave discharge, a flame, and when thermalizing nascent excitations with an inert diluent. This result underscores the importance of the separate potential surfaces which correlate to the product spin-orbit states, and the small amount of 2Π3/2 population can be accounted for by nonadiabatic coupling during dissociation, and/or ``freezing'' the amount of S1 character in an excited precursor in which S0 and S1 are coupled nonradiatively. We note that such electronic specificity should be dealt with in the analogous recombination reactions.

Smarcal1-Mediated Fork Reversal Triggers Mre11-Dependent Degradation of Nascent DNA in the Absence of Brca2 and Stable Rad51 Nucleofilaments.

PubMed

Kolinjivadi, Arun Mouli; Sannino, Vincenzo; De Antoni, Anna; Zadorozhny, Karina; Kilkenny, Mairi; Técher, Hervé; Baldi, Giorgio; Shen, Rong; Ciccia, Alberto; Pellegrini, Luca; Krejci, Lumir; Costanzo, Vincenzo

2017-09-07

Brca2 deficiency causes Mre11-dependent degradation of nascent DNA at stalled forks, leading to cell lethality. To understand the molecular mechanisms underlying this process, we isolated Xenopus laevis Brca2. We demonstrated that Brca2 protein prevents single-stranded DNA gap accumulation at replication fork junctions and behind them by promoting Rad51 binding to replicating DNA. Without Brca2, forks with persistent gaps are converted by Smarcal1 into reversed forks, triggering extensive Mre11-dependent nascent DNA degradation. Stable Rad51 nucleofilaments, but not RPA or Rad51 T131P mutant proteins, directly prevent Mre11-dependent DNA degradation. Mre11 inhibition instead promotes reversed fork accumulation in the absence of Brca2. Rad51 directly interacts with the Pol α N-terminal domain, promoting Pol α and δ binding to stalled replication forks. This interaction likely promotes replication fork restart and gap avoidance. These results indicate that Brca2 and Rad51 prevent formation of abnormal DNA replication intermediates, whose processing by Smarcal1 and Mre11 predisposes to genome instability. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Isolation of nucleoli from Ehrlich ascites tumor cells and dynamics of nascent RNA within isolated nucleoli.

PubMed

Thiry, Marc; Ploton, Dominique

2008-01-01

Here we describe a new, rapid method for isolating nucleoli from Ehrlich tumor cells that preserves their morphological integrity and high transcriptional activity. Until now, methods for isolation of nucleoli were generally assumed to empty one of their three main compartments, the fibrillar center, of its contents. This new method consists of sonicating cells in an isotonic medium containing MgSO(4), spermidine, and spermine, followed by separation of nucleoli through a Percoll density gradient. Using the nonisotopic approach of labelling with BrUTP, we have further investigated the dynamics of nascent ribosomal RNAs (rRNAs) within morphologically intact isolated nucleoli at the electron microscope level. We show that ribosomal transcripts are elongated in the cortex of the fibrillar center and then enter the surrounding dense fibrillar component.

Comparative Dynamics of Retrograde Actin Flow and Focal Adhesions: Formation of Nascent Adhesions Triggers Transition from Fast to Slow Flow

PubMed Central

Alexandrova, Antonina Y.; Arnold, Katya; Schaub, Sébastien; Vasiliev, Jury M.; Meister, Jean-Jacques; Bershadsky, Alexander D.; Verkhovsky, Alexander B.

2008-01-01

Dynamic actin network at the leading edge of the cell is linked to the extracellular matrix through focal adhesions (FAs), and at the same time it undergoes retrograde flow with different dynamics in two distinct zones: the lamellipodium (peripheral zone of fast flow), and the lamellum (zone of slow flow located between the lamellipodium and the cell body). Cell migration involves expansion of both the lamellipodium and the lamellum, as well as formation of new FAs, but it is largely unknown how the position of the boundary between the two flow zones is defined, and how FAs and actin flow mutually influence each other. We investigated dynamic relationship between focal adhesions and the boundary between the two flow zones in spreading cells. Nascent FAs first appeared in the lamellipodium. Within seconds after the formation of new FAs, the rate of actin flow decreased locally, and the lamellipodium/lamellum boundary advanced towards the new FAs. Blocking fast actin flow with cytochalasin D resulted in rapid dissolution of nascent FAs. In the absence of FAs (spreading on poly-L-lysine-coated surfaces) retrograde flow was uniform and the velocity transition was not observed. We conclude that formation of FAs depends on actin dynamics, and in its turn, affects the dynamics of actin flow by triggering transition from fast to slow flow. Extension of the cell edge thus proceeds through a cycle of lamellipodium protrusion, formation of new FAs, advance of the lamellum, and protrusion of the lamellipodium from the new base. PMID:18800171

Position-specific binding of FUS to nascent RNA regulates mRNA length

PubMed Central

Masuda, Akio; Takeda, Jun-ichi; Okuno, Tatsuya; Okamoto, Takaaki; Ohkawara, Bisei; Ito, Mikako; Ishigaki, Shinsuke; Sobue, Gen

2015-01-01

More than half of all human genes produce prematurely terminated polyadenylated short mRNAs. However, the underlying mechanisms remain largely elusive. CLIP-seq (cross-linking immunoprecipitation [CLIP] combined with deep sequencing) of FUS (fused in sarcoma) in neuronal cells showed that FUS is frequently clustered around an alternative polyadenylation (APA) site of nascent RNA. ChIP-seq (chromatin immunoprecipitation [ChIP] combined with deep sequencing) of RNA polymerase II (RNAP II) demonstrated that FUS stalls RNAP II and prematurely terminates transcription. When an APA site is located upstream of an FUS cluster, FUS enhances polyadenylation by recruiting CPSF160 and up-regulates the alternative short transcript. In contrast, when an APA site is located downstream from an FUS cluster, polyadenylation is not activated, and the RNAP II-suppressing effect of FUS leads to down-regulation of the alternative short transcript. CAGE-seq (cap analysis of gene expression [CAGE] combined with deep sequencing) and PolyA-seq (a strand-specific and quantitative method for high-throughput sequencing of 3' ends of polyadenylated transcripts) revealed that position-specific regulation of mRNA lengths by FUS is operational in two-thirds of transcripts in neuronal cells, with enrichment in genes involved in synaptic activities. PMID:25995189

Automated high-level disinfection of nonchanneled flexible endoscopes: duty cycles and endoscope repair.

PubMed

Statham, Melissa McCarty; Willging, J Paul

2010-10-01

Guidelines issued by the Association of Operating Room Nurses and the Association of Professionals in Infection Control and Epidemiology recommend high-level disinfection (HLD) for semicritical instruments, such as flexible endoscopes. We aim to examine the durability of endoscopes to continued use and automated HLD. We report the number of duty cycles a flexible endoscope can withstand before repairs should be anticipated. Retrospective review. A total of 4,336 endoscopic exams and subsequent disinfection cycles were performed with 60 flexible endoscopes in an outpatient tertiary pediatric otolaryngology practice from 2005 to 2009. All endoscopes were systemically cleaned with mechanical cleansing followed by leak testing, enzymatic cleaning, and exposure to Orthophthaldehyde (0.55%) for 5 minutes at a temperature of at least 25°C, followed by rinsing for 3 minutes. A total of 77 repairs were performed, 48 major (average cost $3,815.97), and 29 minor (average cost $326.85). On average, the 2.2-mm flexible endoscopes were utilized for 61.9 examinations before major repair was needed, whereas the 3.6 mm endoscopes were utilized for 154.5 exams before needing minor repairs. No major repairs have been needed to date on the 3.6-mm endoscopes. Automated endoscope reprocessor use for HLD is an effective means to disinfect and process flexible endoscopes. This minimizes variability in the processing of the endoscopes and maximizes the rate of successful HLD. Even when utilizing standardized, automated HLD and limiting the number of personnel processing the endoscopes, smaller fiberoptic endoscopes demonstrate a shortened time interval between repairs than that seen with the larger endoscopes. Laryngoscope, 2010.

A PHASED REHABILITATION PROTOCOL FOR ATHLETES WITH LUMBAR INTERVERTEBRAL DISC HERNIATION

PubMed Central

VanGelder, Leonard H.; Vaughn, Daniel W.

2013-01-01

Conservative non-surgical management of a herniated lumbar intervertebral disc (HLD) in athletes is a complex task due to the dramatic forces imparted on the spine during sport participation. The demands placed upon the athlete during rehabilitation and return to sport are unique not only from a sport specific perspective, but also regarding return to the sport strength and conditioning programs utilized for sport preparation. Many prescriptions fail to address postural and motor control faults specific to athletic development, which may prevent full return to sport after suffering a HLD or predispose the athlete to future exacerbations of a HLD. Strength exercises involving squatting, deadlifting, and Olympic power lifts are large components of the typical athlete's conditioning program, therefore some progressions are provided to address potential underlying problems in the athlete's technique that may have contributed to their HLD in the first place. The purpose of this clinical commentary is to propose a framework for rehabilitation that is built around the phases of healing of the disc. Phase I: Non-Rotational/Non-Flexion Phase (Acute Inflammatory Phase), Phase II: Counter rotation/Flexion Phase (Repair Phase), Phase III: Rotational Phase/Power development (Remodeling Phase), and Phase IV: Full return to sport. This clinical commentary provides a theoretical basis for these phases based on available literature as well as reviewing many popular current practice trends in the management of an HLD. The authors recognize the limits of any general exercise rehabilitation recommendation with regard to return to sport, as well as any general strength and conditioning program. It is vital that an individual assessment and prescription is made for every athlete which reviews and addresses movement in all planes of motion under all necessary extrinsic and intrinsic demands to that athlete. Level of Evidence: 5 PMID:24175134

5S Ribosomal RNA Is an Essential Component of a Nascent Ribosomal Precursor Complex that Regulates the Hdm2-p53 Checkpoint

PubMed Central

Donati, Giulio; Peddigari, Suresh; Mercer, Carol A.; Thomas, George

2013-01-01

SUMMARY Recently, we demonstrated that RPL5 and RPL11 act in a mutually dependent manner to inhibit Hdm2 and stabilize p53 following impaired ribosome biogenesis. Given that RPL5 and RPL11 form a preribosomal complex with noncoding 5S ribosomal RNA (rRNA) and the three have been implicated in the p53 response, we reasoned they may be part of an Hdm2-inhibitory complex. Here, we show that small interfering RNAs directed against 5S rRNA have no effect on total or nascent levels of the noncoding rRNA, though they prevent the reported Hdm4 inhibition of p53. To achieve efficient inhibition of 5S rRNA synthesis, we targeted TFIIIA, a specific RNA polymerase III cofactor, which, like depletion of either RPL5 or RPL11, did not induce p53. Instead, 5S rRNA acts in a dependent manner with RPL5 and RPL11 to inhibit Hdm2 and stabilize p53. Moreover, depletion of any one of the three components abolished the binding of the other two to Hdm2, explaining their common dependence. Finally, we demonstrate that the RPL5/RPL11/5S rRNA preribosomal complex is redirected from assembly into nascent 60S ribosomes to Hdm2 inhibition as a consequence of impaired ribosome biogenesis. Thus, the activation of the Hdm2-inhibitory complex is not a passive but a regulated event, whose potential role in tumor suppression has been recently noted. PMID:23831031

5S ribosomal RNA is an essential component of a nascent ribosomal precursor complex that regulates the Hdm2-p53 checkpoint.

PubMed

Donati, Giulio; Peddigari, Suresh; Mercer, Carol A; Thomas, George

2013-07-11

Recently, we demonstrated that RPL5 and RPL11 act in a mutually dependent manner to inhibit Hdm2 and stabilize p53 following impaired ribosome biogenesis. Given that RPL5 and RPL11 form a preribosomal complex with noncoding 5S ribosomal RNA (rRNA) and the three have been implicated in the p53 response, we reasoned they may be part of an Hdm2-inhibitory complex. Here, we show that small interfering RNAs directed against 5S rRNA have no effect on total or nascent levels of the noncoding rRNA, though they prevent the reported Hdm4 inhibition of p53. To achieve efficient inhibition of 5S rRNA synthesis, we targeted TFIIIA, a specific RNA polymerase III cofactor, which, like depletion of either RPL5 or RPL11, did not induce p53. Instead, 5S rRNA acts in a dependent manner with RPL5 and RPL11 to inhibit Hdm2 and stabilize p53. Moreover, depletion of any one of the three components abolished the binding of the other two to Hdm2, explaining their common dependence. Finally, we demonstrate that the RPL5/RPL11/5S rRNA preribosomal complex is redirected from assembly into nascent 60S ribosomes to Hdm2 inhibition as a consequence of impaired ribosome biogenesis. Thus, the activation of the Hdm2-inhibitory complex is not a passive but a regulated event, whose potential role in tumor suppression has been recently noted. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Mycobacterium massiliense BRA100 strain recovered from postsurgical infections: resistance to high concentrations of glutaraldehyde and alternative solutions for high level disinfection.

PubMed

Lorena, Nádia Suely de Oliveira; Pitombo, Marcos Bettini; Côrtes, Patrícia Barbur; Maya, Maria Cristina Araújo; Silva, Marlei Gomes da; Carvalho, Ana Carolina da Silva; Coelho, Fábrice Santana; Miyazaki, Neide Hiromi Tokumaru; Marques, Elizabeth Andrade; Chebabo, Alberto; Freitas, Andréa D'Avila; Lupi, Otília; Duarte, Rafael Silva

2010-10-01

To evaluate the minimum inhibitory concentration (MIC) of GTA against these microorganisms and alternative disinfectants for high-level disinfection (HLD). Reference mycobacteria and clinical M. massiliense strains were included in this study. Active cultures were submitted to susceptibility qualitative tests with GTA dilutions (ranging from 1.5% to 8%), and commercial orthophthaldehyde (OPA) and peracetic acid (PA)-based solutions, during the period of exposure as recommended by National Agency of Sanitary Surveillance for HLD. All reference and M. massiliense non-BRA100 strains, recovered from sputum, were susceptible to any GTA concentration, OPA and PA solutions. M. massiliense BRA100 strains presented MIC of 8% GTA and were susceptible to OPA and PA. M. massiliense BRA100 strain is resistant to high GTA concentrations (up to 7%), which proves that this product is non-effective against specific rapidly growing mycobacteria and should be substituted by OPA or PA-based solutions for HLD.

CDK1 promotes nascent DNA synthesis and induces resistance of cancer cells to DNA-damaging therapeutic agents

PubMed Central

Liao, Hongwei; Ji, Fang; Geng, Xinwei; Xing, Meichun; Li, Wen; Chen, Zhihua; Shen, Huahao; Ying, Songmin

2017-01-01

Cyclin dependent kinase 1 (CDK1) is essential for cell viability and plays a vital role in many biological events including cell cycle control, DNA damage repair, and checkpoint activation. Here, we identify an unanticipated role for CDK1 in promoting nascent DNA synthesis during S-phase. We report that a short duration of CDK1 inhibition, which does not perturb cell cycle progression, triggers a replication-associated DNA damage response (DDR). This DDR is associated with a disruption of replication fork progression and leads to genome instability. Moreover, we show that compromised CDK1 activity dramatically increases the efficacy of chemotherapeutic agents that kill cancer cells through perturbing DNA replication, including Olaparib, an FDA approved PARP inhibitor. Our study has revealed an important role for CDK1 in the DNA replication program, and suggests that the therapeutic targeting CDK1 may be a novel approach for combination chemotherapy. PMID:29207595

Do chromatin changes around a nascent double strand DNA break spread spherically into linearly non-adjacent chromatin?

PubMed

Savic, Velibor

2013-01-01

In the last decade, a lot has been done in elucidating the sequence of events that occur at the nascent double strand DNA break. Nevertheless, the overall structure formed by the DNA damage response (DDR) factors around the break site, the repair focus, remains poorly understood. Although most of the data presented so far only address events that occur in chromatin in cis around the break, there are strong indications that in mammalian systems it may also occur in trans, analogous to the recent findings showing this if budding yeast. There have been attempts to address the issue but the final proof is still missing due to lack of a proper experimental system. If found to be true, the spatial distribution of DDR factors would have a major impact on the neighboring chromatin both in cis and in trans, significantly affecting local chromatin function; gene transcription and potentially other functions.

The effects of treatment on lipoprotein subfractions evaluated by polyacrylamide gel electrophoresis in patients with autoimmune hypothyroidism and hyperthyroidism.

PubMed

Minarikova, Zuzana; Gaspar, Ludovit; Kruzliak, Peter; Celecová, Zuzana; Oravec, Stanislav

2014-10-10

Atherogenic dyslipoproteinemia is one of the most important risk factor for atherosclerotic changes development. Hypothyroidism is one of the most common causes of secondary dyslipidemias which results from reduced LDL clearance and therefore raised levels of LDL and apoB. Association between small dense LDL (sdLDL) presentation and thyroid status has been examinated using polyacrylamide gel electrophoresis for lipoprotein subfractions evaluation. 40 patients with diagnosed autoimmune hypothyroidism and 30 patients with autoimmune hyperthyroidism were treated with thyroxine replacement or thyreo-suppressive treatment. In both groups lipid profiles, LDL subractions, apolipoproteins (apoA1, apoB), apoA1/apoB ratio and atherogenic index of plazma (AIP) were examined before treatment and in state of euthyreosis. Thyroxine replacement therapy significantly reduced levels of total cholesterol (TC), LDL, triglycerides (TG) and also decreased levels of sdLDL (8,55±11,671 vs 0,83±1,693mg/dl; p<0,001), apoB and AIP. For estimation of atherogenic lipoprotein profile existence an AIP evaluation seems to be better than apoB measurement because of the more evident relationship with sdLDL (r=0,538; p<0,01). Thyreo-suppressive therapy significantly increased levels of TC, LDL, TG and apoB. The sdLDL was not found in hyperthyroid patients. Atherogenic lipoprotein profile was present in 52.5% of hypothyroid subjects, which is higher prevalence than in normal, age-related population. Substitution treatment leads to an improvement of the lipid levels, TG, apoB, AIP and LDL subclasses. It significantly changed the presentation of sdLDL - we noticed shift to large, less atherogenic LDL particles. Significantly positive correlation between sdLDL and TAG; sdLDL and VLDL alerts to hypertriglyceridemia as a major cardiovascular risk factor.

Interactions between stepwise-eluted sub-fractions of fulvic acids and protons revealed by fluorescence titration combined with EEM-PARAFAC.

PubMed

Song, Fanhao; Wu, Fengchang; Guo, Fei; Wang, Hao; Feng, Weiying; Zhou, Min; Deng, Yanghui; Bai, Yingchen; Xing, Baoshan; Giesy, John P

2017-12-15

In aquatic environments, pH can control environmental behaviors of fulvic acid (FA) via regulating hydrolysis of functional groups. Sub-fractions of FA, eluted using pyrophosphate buffers with initial pHs of 3.0 (FA 3 ), 5.0 (FA 5 ), 7.0 (FA 7 ), 9.0 (FA 9 ) and 13.0 (FA 13 ), were used to explore interactions between the various, operationally defined, FA fractions and protons, by use of EEM-PARAFAC analysis. Splitting of peaks (FA 3 and FA 13 ), merging of peaks (FA 7 ), disappearance of peaks (FA 9 and FA 13 ), and red/blue-shifting of peaks were observed during fluorescence titration. Fulvic-like components were identified from FA 3 -FA 13 , and protein-like components were observed in fractions FA 9 and FA 13 . There primary compounds (carboxylic-like, phenolic-like, and protein-like chromophores) in PARAFAC components were distinguished based on acid-base properties. Dissociation constants (pK a ) for fulvic-like components with proton ranged from 2.43 to 4.13 in an acidic pH and from 9.95 to 11.27 at basic pH. These results might be due to protonation of di-carboxylate and phenolic functional groups. At basic pH, pK a values of protein-like components (9.77-10.13) were similar to those of amino acids. However, at acidic pH, pK a values of protein-like components, which ranged from 3.33 to 4.22, were 1-2units greater than those of amino acids. Results presented here, will benefit understanding of environmental behaviors of FA, as well as interactions of FA with environmental contaminants. Copyright © 2017 Elsevier B.V. All rights reserved.

A set of autosomal multiple InDel markers for forensic application and population genetic analysis in the Chinese Xinjiang Hui group.

PubMed

Xie, Tong; Guo, Yuxin; Chen, Ling; Fang, Yating; Tai, Yunchun; Zhou, Yongsong; Qiu, Pingming; Zhu, Bofeng

2018-07-01

In recent years, insertion/deletion (InDel) markers have become a promising and useful supporting tool in forensic identification cases and biogeographic research field. In this study, 30 InDel loci were explored to reveal the genetic diversities and genetic relationships between Chinese Xinjiang Hui group and the 25 previously reported populations using various biostatistics methods such as forensic statistical parameter analysis, phylogenetic reconstruction, multi-dimensional scaling, principal component analysis, and STRUCTURE analysis. No deviations from Hardy-Weinberg equilibrium tests were found at all 30 loci in the Chinese Xinjiang Hui group. The observed heterozygosity and expected heterozygosity ranged from 0.1971 (HLD118) to 0.5092 (HLD92), 0.2222 (HLD118) to 0.5000 (HLD6), respectively. The cumulative probability of exclusion and combined power of discrimination were 0.988849 and 0.99999999999378, respectively, which indicated that these 30 loci could be qualified for personal identification and used as complementary genetic markers for paternity tests in forensic cases. The results of present research based on the different methods of population genetic analysis revealed that the Chinese Xinjiang Hui group had close relationships with most Chinese groups, especially Han populations. In spite of this, for a better understanding of genetic background of the Chinese Xinjiang Hui group, more molecular genetic markers such as ancestry informative markers, single nucleotide polymorphisms (SNPs), and copy number variations will be conducted in future studies. Copyright © 2018 Elsevier B.V. All rights reserved.

Do chromatin changes around a nascent double strand DNA break spread spherically into linearly non-adjacent chromatin?

PubMed Central

Savic, Velibor

2013-01-01

In the last decade, a lot has been done in elucidating the sequence of events that occur at the nascent double strand DNA break. Nevertheless, the overall structure formed by the DNA damage response (DDR) factors around the break site, the repair focus, remains poorly understood. Although most of the data presented so far only address events that occur in chromatin in cis around the break, there are strong indications that in mammalian systems it may also occur in trans, analogous to the recent findings showing this if budding yeast. There have been attempts to address the issue but the final proof is still missing due to lack of a proper experimental system. If found to be true, the spatial distribution of DDR factors would have a major impact on the neighboring chromatin both in cis and in trans, significantly affecting local chromatin function; gene transcription and potentially other functions. PMID:23882282

Decay dynamics of nascent acetonitrile and nitromethane dipole-bound anions produced by intracluster charge-transfer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yandell, Margaret A.; King, Sarah B.; Neumark, Daniel M., E-mail: dneumark@berkeley.edu

2014-05-14

Decay dynamics of nascent dipole bound states of acetonitrile and nitromethane are examined using time-resolved photoelectron imaging of iodide-acetonitrile (I{sup −}·CH{sub 3}CN) and iodide-nitromethane (I{sup −}·CH{sub 3}NO{sub 2}) complexes. Dipole-bound anions are created by UV-initiated electron transfer to the molecule of interest from the associated iodide ion at energies just below the vertical detachment energy of the halide-molecule complex. The acetonitrile anion is observed to decay biexponentially with time constants in the range of 4–900 ps. In contrast, the dipole bound state of nitromethane decays rapidly over 400 fs to form the valence bound anion. The nitromethane valence anion speciesmore » then decays biexponentially with time constants of 2 ps and 1200 ps. The biexponential decay dynamics in acetonitrile are interpreted as iodine atom loss and autodetachment from the excited dipole-bound anion, followed by slower autodetachment of the relaxed metastable ion, while the dynamics of the nitromethane system suggest that a dipole-bound anion to valence anion transition proceeds via intramolecular vibrational energy redistribution to nitro group modes in the vicinity of the iodine atom.« less

Decay dynamics of nascent acetonitrile and nitromethane dipole-bound anions produced by intracluster charge-transfer.

PubMed

Yandell, Margaret A; King, Sarah B; Neumark, Daniel M

2014-05-14

Decay dynamics of nascent dipole bound states of acetonitrile and nitromethane are examined using time-resolved photoelectron imaging of iodide-acetonitrile (I(-)·CH3CN) and iodide-nitromethane (I(-)·CH3NO2) complexes. Dipole-bound anions are created by UV-initiated electron transfer to the molecule of interest from the associated iodide ion at energies just below the vertical detachment energy of the halide-molecule complex. The acetonitrile anion is observed to decay biexponentially with time constants in the range of 4-900 ps. In contrast, the dipole bound state of nitromethane decays rapidly over 400 fs to form the valence bound anion. The nitromethane valence anion species then decays biexponentially with time constants of 2 ps and 1200 ps. The biexponential decay dynamics in acetonitrile are interpreted as iodine atom loss and autodetachment from the excited dipole-bound anion, followed by slower autodetachment of the relaxed metastable ion, while the dynamics of the nitromethane system suggest that a dipole-bound anion to valence anion transition proceeds via intramolecular vibrational energy redistribution to nitro group modes in the vicinity of the iodine atom.

Mechanical Modulation of Nascent Stem Cell Lineage Commitment in Tissue Engineering Scaffolds

PubMed Central

Song, Min Jae; Dean, David; Tate, Melissa L. Knothe

2013-01-01

Taking inspiration from tissue morphogenesis in utero, this study tests the concept of using tissue engineering scaffolds as delivery devices to modulate emergent structure-function relationships at early stages of tissue genesis. We report on the use of a combined computational fluid dynamics (CFD) modeling, advanced manufacturing methods, and experimental fluid mechanics (micro-piv and strain mapping) for the prospective design of tissue engineering scaffold geometries that deliver spatially resolved mechanical cues to cells seeded within. When subjected to a constant magnitude global flow regime, the local scaffold geometry dictates the magnitudes of mechanical stresses and strains experienced by a given cell, and in a spatially resolved fashion, similar to patterning during morphogenesis. In addition, early markers of mesenchymal stem cell lineage commitment relate significantly to the local mechanical environment of the cell. Finally, by plotting the range of stress-strain states for all data corresponding to nascent cell lineage commitment (95% CI), we begin to “map the mechanome”, defining stress-strain states most conducive to targeted cell fates. In sum, we provide a library of reference mechanical cues that can be delivered to cells seeded on tissue engineering scaffolds to guide target tissue phenotypes in a temporally and spatially resolved manner. Knowledge of these effects allows for prospective scaffold design optimization using virtual models prior to prototyping and clinical implementation. Finally, this approach enables the development of next generation scaffolds cum delivery devices for genesis of complex tissues with heterogenous properties, e.g., organs, joints or interface tissues such as growth plates. PMID:23660249

Mechanical modulation of nascent stem cell lineage commitment in tissue engineering scaffolds.

PubMed

Song, Min Jae; Dean, David; Knothe Tate, Melissa L

2013-07-01

Taking inspiration from tissue morphogenesis in utero, this study tests the concept of using tissue engineering scaffolds as delivery devices to modulate emergent structure-function relationships at early stages of tissue genesis. We report on the use of a combined computational fluid dynamics (CFD) modeling, advanced manufacturing methods, and experimental fluid mechanics (micro-piv and strain mapping) for the prospective design of tissue engineering scaffold geometries that deliver spatially resolved mechanical cues to stem cells seeded within. When subjected to a constant magnitude global flow regime, the local scaffold geometry dictates the magnitudes of mechanical stresses and strains experienced by a given cell, and in a spatially resolved fashion, similar to patterning during morphogenesis. In addition, early markers of mesenchymal stem cell lineage commitment relate significantly to the local mechanical environment of the cell. Finally, by plotting the range of stress-strain states for all data corresponding to nascent cell lineage commitment (95% CI), we begin to "map the mechanome", defining stress-strain states most conducive to targeted cell fates. In sum, we provide a library of reference mechanical cues that can be delivered to cells seeded on tissue engineering scaffolds to guide target tissue phenotypes in a temporally and spatially resolved manner. Knowledge of these effects allows for prospective scaffold design optimization using virtual models prior to prototyping and clinical implementation. Finally, this approach enables the development of next generation scaffolds cum delivery devices for genesis of complex tissues with heterogenous properties, e.g., organs, joints or interface tissues such as growth plates. Copyright © 2013 Elsevier Ltd. All rights reserved.

Ultrafast chemical interface scattering as an additional decay channel for nascent nonthermal electrons in small metal nanoparticles.

PubMed

Bauer, Christophe; Abid, Jean-Pierre; Fermin, David; Girault, Hubert H

2004-05-15

The use of 4.2 nm gold nanoparticles wrapped in an adsorbates shell and embedded in a TiO2 metal oxide matrix gives the opportunity to investigate ultrafast electron-electron scattering dynamics in combination with electronic surface phenomena via the surface plasmon lifetimes. These gold nanoparticles (NPs) exhibit a large nonclassical broadening of the surface plasmon band, which is attributed to a chemical interface damping. The acceleration of the loss of surface plasmon phase coherence indicates that the energy and the momentum of the collective electrons can be dissipated into electronic affinity levels of adsorbates. As a result of the preparation process, gold NPs are wrapped in a shell of sulfate compounds that gives rise to a large density of interfacial molecules confined between Au and TiO2, as revealed by Fourier-transform-infrared spectroscopy. A detailed analysis of the transient absorption spectra obtained by broadband femtosecond transient absorption spectroscopy allows separating electron-electron and electron-phonon interaction. Internal thermalization times (electron-electron scattering) are determined by probing the decay of nascent nonthermal electrons (NNEs) and the build-up of the Fermi-Dirac electron distribution, giving time constants of 540 to 760 fs at 0.42 and 0.34 eV from the Fermi level, respectively. Comparison with literature data reveals that lifetimes of NNEs measured for these small gold NPs are more than four times longer than for silver NPs with similar sizes. The surprisingly long internal thermalization time is attributed to an additional decay mechanism (besides the classical e-e scattering) for the energy loss of NNEs, identified as the ultrafast chemical interface scattering process. NNEs experience an inelastic resonant scattering process into unoccupied electronic states of adsorbates, that directly act as an efficient heat bath, via the excitation of molecular vibrational modes. The two-temperature model is no longer

Sensory properties of wine tannin fractions: implications for in-mouth sensory properties.

PubMed

McRae, Jacqui M; Schulkin, Alex; Kassara, Stella; Holt, Helen E; Smith, Paul A

2013-01-23

Different molecular structures of grape tannins have been shown to influence astringency, however, the in-mouth sensory effects of different molecular structures in red wine tannins remains to be established. The objective of this research was to assess the impact of wine tannin structure on in-mouth sensory properties. Wine tannin was isolated from Cabernet Sauvignon wines of two vintages (3 and 7 years old) and separated into two structurally distinct subfractions with liquid-liquid fractionation using butanol and water. The aqueous subfractions had greater mean degree of polymerization (mDp) and contained a higher proportion of epigallocatechin subunits than the butanol-soluble subfractions, while the older wine tannin fractions showed fewer epicatechin gallate subunits than the younger tannin fractions. The red wine had approximately 3:1 mass ratio of the aqueous and butanol tannin subfractions which approximated an equimolar ratio of tannin in each subfraction. Descriptive sensory analysis of the tannin subfractions in model wine at equimolar concentrations revealed that the larger, more water-soluble wine tannin subfractions from both wines were perceived as more astringent than the smaller, more hydrophobic and more highly pigmented butanol-soluble subfractions, which were perceived as hotter and more bitter. Partial least squares analysis indicated that the greater hydrophobicity and color incorporation in the butanol fractions was negatively associated with astringency, and these characteristics are also associated with aged wine tannins. As the larger, water-soluble tannins had a greater impact on the overall wine astringency, winemaking processes that modulate concentrations of these are likely to most significantly influence astringency.

Histone H1 heterogeneity in the midge, Chironomus thummi. Structural comparison of the H1 variants in an organism where their intrachromosomal localization is possible.

PubMed

Hoyer-Fender, S; Grossbach, U

1988-09-01

1. Seven subfractions of histone H1 have been isolated and purified from larvae of Chironomus thummi (Diptera). They have been denominated I-1, II-1, II-2, II-3, III-1, III-2, and III-3, according to the order of migration in two steps of preparative electrophoresis. 2. The amino acid compositions are similar to those of other H1 histones. Subfractions I-1 and II-1 were found to contain one methionine and two tyrosine residues, II-2 contained two methionine and three tyrosine residues, and III-1 one methionine and three tyrosine residues. The other subfractions contained one or two methionine and two or three tyrosine residues. For subfractions I-1 and II-1 a chain length of about 252 amino acids was estimated. 3. Peptide pattern analyses after chemical cleavage at the methionine and tyrosine residues, and enzymatic cleavage with thrombin and chymotrypsin, respectively, showed that all subfractions have different individual primary structures. A comparison of peptide sizes and of the positions in the peptide patterns of epitopes recognized by monoclonal antibodies was made to check whether some of the subfractions could arise by proteolytic degradation of others. This possibility can be excluded for five of the subfractions and is very improbable for the two others. Treatment of C. thummi H1 with alkaline phosphatase did not change the pattern of subfractions, while the phosphorylated subfraction of histone H2A disappeared after this treatment. Most and very probably all subfractions are thus H1 sequence variants. 4. Inbred strains and individual larvae of C. thummi were found to comprise all seven variants. The H1 heterogeneity can therefore not be due to allelic polymorphism. Salivary gland nuclei were found to contain variant I-1 and at least some of the other variants. 5. H1 from Drosophila melanogaster and from calf thymus were used as reference molecules in all cleavage experiments and yielded the peptide patterns expected from the sequence. The comparison

Human Lactoferrin and Peptides Derived from a Surface-Exposed Helical Region Reduce Experimental Escherichia coli Urinary Tract Infection in Mice

PubMed Central

Håversen, Liliana A.; Engberg, Inga; Baltzer, Lars; Dolphin, Gunnar; Hanson, Lars Å.; Mattsby-Baltzer, Inger

2000-01-01

Lactoferrin (LF) is a multifunctional immunoregulatory protein that has been associated with host defense at mucosal surfaces through its antibacterial properties. The antibacterial and anti-inflammatory properties of LF were further explored with an animal model of experimental urinary tract infection. Bovine LF (bLF), human LF (hLF), and synthetic peptide sequences based on the antibacterial region of hLF (amino acid residues 16 to 40 [HLD1] and 18 to 40 [HLD2]) were given orally to female mice 30 min after the instillation of 108 Escherichia coli bacteria into the urinary bladder. The control groups received phosphate-buffered saline or water. C3H/Tif mice were treated with hLF or bLF, and C3H/HeN mice were treated with bLF only. The numbers of bacteria in the kidneys and bladder of C3H/Tif and C3H/HeN mice were significantly reduced 24 h later by the LF treatments compared to the findings for the control group. The hLF-treated group showed the strongest reduction compared with the vehicle-treated-group (P values were 0.009 and 0.0001 for the kidneys and bladder, respectively). The urinary leukocyte response was diminished in the hLF-treated group. The hLF treatment also significantly reduced the urinary interleukin-6 (IL-6) levels at 2 h and the systemic IL-6 levels at 24 h after infection (P values were 0.04 and < 0.002, respectively). In the bLF-treated animals, no such strong anti-inflammatory effects were obtained. In another series of experiments, C3H/Tif mice perorally treated with HLD1 or HLD2 also showed reduced numbers of bacteria in the kidneys compared with the vehicle-treated mice, although the results were significantly different only for HLD2 (P < 0.01). Analysis of urine from hLF-fed C3H/Tif mice showed that hLF was excreted into the urinary tract at 2 h after feeding. Testing of the in vitro bactericidal activity of LF (1 mg/ml) or the peptides (0.1 mg/ml) in mouse urine against the E. coli bacteria revealed moderate killing only by HLD2. In

Sharp Transition from Nonmetallic Au246 to Metallic Au279 with Nascent Surface Plasmon Resonance.

PubMed

Higaki, Tatsuya; Zhou, Meng; Lambright, Kelly J; Kirschbaum, Kristin; Sfeir, Matthew Y; Jin, Rongchao

2018-05-02

The optical properties of metal nanoparticles have attracted wide interest. Recent progress in controlling nanoparticles with atomic precision (often called nanoclusters) provide new opportunities for investigating many fundamental questions, such as the transition from excitonic to plasmonic state, which is a central question in metal nanoparticle research because it provides insights into the origin of surface plasmon resonance (SPR) as well as the formation of metallic bond. However, this question still remains elusive because of the extreme difficulty in preparing atomically precise nanoparticles larger than 2 nm. Here we report the synthesis and optical properties of an atomically precise Au 279 (SR) 84 nanocluster. Femtosecond transient absorption spectroscopic analysis reveals that the Au 279 nanocluster shows a laser power dependence in its excited state lifetime, indicating metallic state of the particle, in contrast with the nonmetallic electronic structure of the Au 246 (SR) 80 nanocluster. Steady-state absorption spectra reveal that the nascent plasmon band of Au 279 at 506 nm shows no peak shift even down to 60 K, consistent with plasmon behavior. The sharp transition from nonmetallic Au 246 to metallic Au 279 is surprising and will stimulate future theoretical work on the transition and many other relevant issues.

Quantum-state resolved reactive scattering at the gas-liquid interface: F+squalane (C30H62) dynamics via high-resolution infrared absorption of nascent HF(v,J).

PubMed

Zolot, Alexander M; Dagdigian, Paul J; Nesbitt, David J

2008-11-21

Exothermic chemical reaction dynamics at the gas-liquid interface have been investigated by colliding a supersonic beam of F atoms [E(com)=0.7(3) kcalmol] with a continuously refreshed liquid hydrocarbon (squalane) surface under high vacuum conditions. Absolute HF(v,J) product densities are determined by infrared laser absorption spectroscopy, with velocity distributions along the probe axis derived from high resolution Dopplerimetry. Nascent HF(vNascent HF also recoils from the liquid surface with excess translational energy, resulting in Doppler broadened linewidths that increase systematically with internal HF excitation. The data are consistent with microscopic branching in HF-surface dynamics following the reactive event, with (i) a direct reactive scattering fraction of newly formed product molecules leaving the surface promptly and (ii) a trapping desorption fraction that accommodates rotationally (though still not vibrationally) with the bulk liquid. Comparison with analogous gas phase F+hydrocarbon processes reveals that the liquid acts as a partial "heat sink" for vibrational energy flow on the time scale of the chemical reaction event.

Quantum-state resolved reactive scattering at the gas-liquid interface: F +squalane (C30H62) dynamics via high-resolution infrared absorption of nascent HF(v,J)

NASA Astrophysics Data System (ADS)

Zolot, Alexander M.; Dagdigian, Paul J.; Nesbitt, David J.

2008-11-01

Exothermic chemical reaction dynamics at the gas-liquid interface have been investigated by colliding a supersonic beam of F atoms [Ecom=0.7(3)kcal/mol] with a continuously refreshed liquid hydrocarbon (squalane) surface under high vacuum conditions. Absolute HF(v,J) product densities are determined by infrared laser absorption spectroscopy, with velocity distributions along the probe axis derived from high resolution Dopplerimetry. Nascent HF(v ⩽3) products are formed in a highly nonequilibrium (inverted) vibrational distribution [⟨Evib⟩=13.2(2)kcal/mol], reflecting insufficient time for complete thermal accommodation with the surface prior to desorption. Colder, but still non-Boltzmann, rotational state populations [⟨Erot⟩=1.0(1)kcal/mol] indicate that some fraction of molecules directly scatter into the gas phase without rotationally equilibrating with the surface. Nascent HF also recoils from the liquid surface with excess translational energy, resulting in Doppler broadened linewidths that increase systematically with internal HF excitation. The data are consistent with microscopic branching in HF-surface dynamics following the reactive event, with (i) a direct reactive scattering fraction of newly formed product molecules leaving the surface promptly and (ii) a trapping desorption fraction that accommodates rotationally (though still not vibrationally) with the bulk liquid. Comparison with analogous gas phase F +hydrocarbon processes reveals that the liquid acts as a partial "heat sink" for vibrational energy flow on the time scale of the chemical reaction event.

A Novel Equation-of-State to Model Microemulsion Phase Behavior for Enhanced Oil Recovery Application

NASA Astrophysics Data System (ADS)

Ghosh, Soumyadeep

Surfactant-polymer (SP) floods have significant potential to recover waterflood residual oil in shallow oil reservoirs. A thorough understanding of surfactant-oil-brine phase behavior is critical to the design of chemical EOR floods. While considerable progress has been made in developing surfactants and polymers that increase the potential of a chemical enhanced oil recovery (EOR) project, very little progress has been made to predict phase behavior as a function of formulation variables such as pressure, temperature, and oil equivalent alkane carbon number (EACN). The empirical Hand's plot is still used today to model the microemulsion phase behavior with little predictive capability as these and other formulation variables change. Such models could lead to incorrect recovery predictions and improper flood designs. Reservoir crudes also contain acidic components (primarily naphthenic acids), which undergo neutralization to form soaps in the presence of alkali. The generated soaps perform synergistically with injected synthetic surfactants to mobilize waterflood residual oil in what is termed alkali-surfactant-polymer (ASP) flooding. The addition of alkali, however, complicates the measurement and prediction of the microemulsion phase behavior that forms with acidic crudes. In this dissertation, we account for pressure changes in the hydrophilic-lipophilic difference (HLD) equation. This new HLD equation is coupled with the net-average curvature (NAC) model to predict phase volumes, solubilization ratios, and microemulsion phase transitions (Winsor II-, III, and II+). This dissertation presents the first modified HLD-NAC model to predict microemulsion phase behavior for live crudes, including optimal solubilization ratio and the salinity width of the three-phase Winsor III region at different temperatures and pressures. This new equation-of-state-like model could significantly aid the design and forecast of chemical floods where key variables change dynamically

Predicting solubilisation features of ternary phase diagrams of fully dilutable lecithin linker microemulsions.

PubMed

Nouraei, Mehdi; Acosta, Edgar J

2017-06-01

Fully dilutable microemulsions (μEs), used to design self-microemulsifying delivery system (SMEDS), are formulated as concentrate solutions containing oil and surfactants, without water. As water is added to dilute these systems, various μEs are produced (water-swollen reverse micelles, bicontinuous systems, and oil-swollen micelles), without the onset of phase separation. Currently, the formulation dilutable μEs follows a trial and error approach that has had a limited success. The objective of this work is to introduce the use of the hydrophilic-lipophilic-difference (HLD) and net-average-curvature (NAC) frameworks to predict the solubilisation features of ternary phase diagrams of lecithin-linker μEs and the use of these predictions to guide the formulation of dilutable μEs. To this end, the characteristic curvatures (Cc) of soybean lecithin (surfactant), glycerol monooleate (lipophilic linker) and polyglycerol caprylate (hydrophilic linker) and the equivalent alkane carbon number (EACN) of ethyl caprate (oil) were obtained via phase scans with reference surfactant-oil systems. These parameters were then used to calculate the HLD of lecithin-linkers-ethyl caprate microemulsions. The calculated HLDs were able to predict the phase transitions observed in the phase scans. The NAC was then used to fit and predict phase volumes obtained from salinity phase scans, and to predict the solubilisation features of ternary phase diagrams of the lecithin-linker formulations. The HLD-NAC predictions were reasonably accurate, and indicated that the largest region for dilutable μEs was obtained with slightly negative HLD values. The NAC framework also predicted, and explained, the changes in microemulsion properties along dilution lines. Copyright © 2017 Elsevier Inc. All rights reserved.

Reactivation of Escherichia coli cells, inactivated by ultraviolet rays, with cell extracts of propionic acid bacteria: Fractionation of the extract

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vorob`eva, L.I.; Khodzhaev, E.Yu.; Ponomareva, G.M.

1995-01-01

Separation of Propionibacterium shermanii extract into fractions and testing them for their reactivating effect on UV-inactivated Escherichia coli AB-1157 cells showed that the activity was associated with the fraction of soluble proteins. The activity was not demonstrated in the fractions of RNA, DNA, ribosomes, or cell walls. Fractional salting out and subsequent testing of the fractions showed two active protein fractions: fraction I (20-40% of ammonium sulfate saturating concentration) and fraction II (60-80%). These fractions were separated by HPLC into seven and eight subfractions, respectively. Reactivating activity was showed in subfraction 4 (fraction I) and subfractions 5 and 6 (fractionmore » II). Electrophoresis showed five and four polypeptides in subfractions 4 and 5, respectively. Subfraction 6 (fraction II) contained one protein with a molecular mass of about 30 kDa. This protein, apparently, was responsible for the protective properties of fraction II. 9 refs., 2 figs., 4 tabs.« less

[The synaptic proteins of the temporal associative area in the neocortex (field Ep) of cats with normal and decreased cognitive capacities].

PubMed

Zakharova (Orlova), E I; Mukhin, E I

1994-01-01

Fractions of light and heavy synaptosomes were prepared from associative temporal area of cat brain, which were previously tested behaviorally for ability to solve the generalization, gnostic and abstraction tasks. The synaptic membrane subfractions and synaptoplasma fractions were isolated and the content of the total protein and of the demasked protein sulfhydryl groups (SH groups) was investigated spectrophotometrically. The maximal content of the demasked SH groups was revealed in the upper subfractions (mainly the membranes of cholinergic synapses) and minimal content--in the lower subfractions (mainly noncholinergic synapses). Significantly smaller total protein content in the upper and middle subfractions of light synaptosomes was found, and more demasked SH groups in the membrane-bound proteins of the upper and middle subfractions of light and heavy synaptosomes was found in the cortex area of the "clever" then "silly" cats. Suggestion concerning characteristic for brains of "clever" cats relatively low total quantity of synapses in the area Ep of the cortex and significantly higher proportion of cholinergic ones is discussed.

Characterization of plasma membrane domains of mouse EL4 lymphoma cells obtained by affinity chromatography on concanavalin A-Sepharose.

PubMed

Szamel, M; Goppelt, M; Resch, K

1985-12-19

Purified plasma membranes of mouse EL4 lymphoma cells were fractionated by means of affinity chromatography on concanavalin A-Sepharose into two subfractions; one (MF1) eluted freely from the affinity column, the second (MF2) adhered specifically to Con A-Sepharose. Both membrane subfractions proved to be of plasma membrane origin, as evidenced by the following criteria. (i) The ratio of cholesterol to phospholipid was nearly identical in plasma membrane and both subfractions. (ii) When isolated plasma membranes were labelled with tritiated NaBH4, both subfractions exhibited identical specific radioactivities. (iii) After enzymatic radioiodination of the cells, the total content of labelled proteins was very similar in isolated plasma membranes and in both subfractions. (iv) Some plasma membrane marker enzymes exhibited nearly identical specific activities in plasma membranes, MF1 or MF2 including gamma-glutamyl transpeptidase, 5'-nucleotidase and Mg2+-ATPase. Both subfractions exhibited characteristic differences. Thus the specific activities of (Na+ + K+)-ATPase, Ca2+-ATPase and lysophosphatidylcholine acyltransferase were several-fold enriched in MF2 compared to MF1. SDS-polyacrylamide gel electrophoresis revealed a different polypeptide composition of the two subfractions. Polypeptides of apparent molecular mass of 116, 95, 42, 39, 30 and 28 kDa were highly enriched in MF2, whereas MF1 contained another set of proteins, of apparent molecular mass of 70, 55 and 24 kDa. The phospholipid fatty acid composition of the subfractions proved to be different, as well, MF2 contained more saturated fatty acids than MF1. The data suggest the existence of plasma membrane domains in the plasma membranes of the mouse EL4 lymphoma cells, containing a set of polypeptides, among others membrane bound enzymes, embedded in a different phospholipid milieu.

Live imaging of prions reveals nascent PrPSc in cell-surface, raft-associated amyloid strings and webs

PubMed Central

Rouvinski, Alexander; Karniely, Sharon; Kounin, Maria; Moussa, Sanaa; Goldberg, Miri D.; Warburg, Gabriela; Lyakhovetsky, Roman; Papy-Garcia, Dulce; Kutzsche, Janine; Korth, Carsten; Carlson, George A.; Godsave, Susan F.; Peters, Peter J.; Luhr, Katarina; Kristensson, Krister

2014-01-01

Mammalian prions refold host glycosylphosphatidylinositol-anchored PrPC into β-sheet–rich PrPSc. PrPSc is rapidly truncated into a C-terminal PrP27-30 core that is stable for days in endolysosomes. The nature of cell-associated prions, their attachment to membranes and rafts, and their subcellular locations are poorly understood; live prion visualization has not previously been achieved. A key obstacle has been the inaccessibility of PrP27-30 epitopes. We overcame this hurdle by focusing on nascent full-length PrPSc rather than on its truncated PrP27-30 product. We show that N-terminal PrPSc epitopes are exposed in their physiological context and visualize, for the first time, PrPSc in living cells. PrPSc resides for hours in unexpected cell-surface, slow moving strings and webs, sheltered from endocytosis. Prion strings observed by light and scanning electron microscopy were thin, micrometer-long structures. They were firmly cell associated, resisted phosphatidylinositol-specific phospholipase C, aligned with raft markers, fluoresced with thioflavin, and were rapidly abolished by anti-prion glycans. Prion strings and webs are the first demonstration of membrane-anchored PrPSc amyloids. PMID:24493590

Evidence for a Nascent Rift in South Sudan: Westward Extension of the East African Rift System?

NASA Astrophysics Data System (ADS)

Maceira, M.; Van Wijk, J. W.; Coblentz, D. D.; Modrak, R. T.

2013-12-01

Joint inversion of seismic and gravity data of eastern Africa reveals a low seismic wave velocity arm stretching from the southern Main Ethiopian rift westward in an east-west direction that has not been noticed in earlier work. The zone of low velocities is located in the upper mantle and is not overlain by a known structural rift expression. We analyzed the local pattern of seismicity and the stresses in the African plate to interpret this low velocity arm. The zone of low velocities is located within the Central African Fold Belt, which dissects the northern and southern portions of the African continent. It is seismically active with small to intermediate sized earthquakes occurring in the crust. Seven earthquake solutions indicate (oblique) normal faulting and low-angle normal faulting with a NS to NNW-SSE opening direction, as well as strike-slip faulting. This pattern of deformation is typically associated with rifting. The present day stress field in northeastern Africa reveals a tensional state of stress at the location of the low velocity arm with an opening direction that corresponds to the earthquake data. We propose that the South Sudan low velocity zone and seismic center are part of an undeveloped, nascent rift arm. The arm stretches from the East African Rift system westward.

The time-dependent distribution of 125I-asialo-orosomucoid-horseradish peroxidase and 131I-immunoglobulin A among three endosomal subfractions isolated from rat liver.

PubMed Central

Kennedy, G; Cooper, C

1988-01-01

Three discrete endosomal fractions showing a time-dependent uptake of radioactive ligand were partially purified from rat liver. The 3,3'-diaminobenzidine (DAB)-induced density-shift protocol of Courtoy, Quintart & Baudhuin [(1984) J. Cell Biol. 98, 870-876] was used to study the distribution among these three endosomal fractions of two ligands with different intracellular destinations. Rats received both 125I-asialo-orosomucoid-horseradish peroxidase (125I-ASOR-HRP) and 131I-dIgA simultaneously by intraportal injection. The liver was fractionated at various times after injection, the three ligand-containing endosomal fractions (A, B and C) were separated and each was subjected separately to the DAB-induced density-shift procedure in which only vesicles containing 125I-ASOR-HRP are increased in density. Information on whether 131I-dIgA was co-localized or segregated from 125I-ASOR-HRP was obtained. The two ligands in the A fraction were partly segregated and partly co-localized, and this distribution appeared to be relatively unchanged with time. The two ligands in the B fraction were co-localized at all times studied. We have tentatively identified the B fraction as a compartment in which vesicle fusion has occurred. The two ligands in the C fraction were also partly co-localized and partly segregated, but the 131I-dIgA became increasingly segregated with time. This represents the first report of the purification of an endosomal subfraction specifically involved in the accumulation of multiple ligands. Images Fig. 7. PMID:3421920

Vancomycin modifies the expression of the agr system in multidrug-resistant Staphylococcus aureus clinical isolates

PubMed Central

Cázares-Domínguez, Vicenta; Ochoa, Sara A.; Cruz-Córdova, Ariadnna; Rodea, Gerardo E.; Escalona, Gerardo; Olivares, Alma L.; Olivares-Trejo, José de Jesús; Velázquez-Guadarrama, Norma; Xicohtencatl-Cortes, Juan

2015-01-01

Staphylococcus aureus is an opportunistic pathogen that colonizes human hosts and causes a wide variety of diseases. Two interacting regulatory systems called agr (accessory gene regulator) and sar (staphylococcal accessory regulator) are involved in the regulation of virulence factors. The aim of this study was to evaluate the effect of vancomycin on hld and spa gene expression during the exponential and post-exponential growth phases in multidrug-resistant (MDR) S. aureus. Methods: Antibiotic susceptibility was evaluated by the standard microdilution method. The phylogenetic profile was obtained by pulsed-field gel electrophoresis (PFGE). Polymorphisms of agr and SCCmec (staphylococcal cassette chromosome mec) were analyzed by multiplex polymerase chain reaction (PCR). The expression levels of hld and spa were analyzed by reverse transcription-PCR. An enzyme-linked immunosorbent assay (ELISA) was performed to detect protein A, and biofilm formation was analyzed via crystal violet staining. Results: In total, 60.60% (20/33) of S. aureus clinical isolates were MDR. Half (10/20) of the MDR S. aureus isolates were distributed in subcluster 10, with >90% similarity among them. In the isolates of this subcluster, a high prevalence (100%) for the agrII and the cassette SCCmec II polymorphisms was found. Our data showed significant increases in hld expression during the post-exponential phase in the presence and absence of vancomycin. Significant increases in spa expression, protein A production and biofilm formation were observed during the post-exponential phase when the MDR S. aureus isolates were challenged with vancomycin. Conclusion: The polymorphism agrII, which is associated with nosocomial isolates, was the most prevalent polymorphism in MDR S. aureus. Additionally, under our study conditions, vancomycin modified hld and spa expression in these clinical isolates. Therefore, vancomycin may regulate alternative systems that jointly participate in the regulation of

Separation and characterization of acetyl and non-acetyl hemicelluloses of Arundo donax by ammonium sulfate precipitation.

PubMed

Peng, Feng; Bian, Jing; Peng, Pai; Xiao, Huan; Ren, Jun-Li; Xu, Feng; Sun, Run-Cang

2012-04-25

Delignified Arundo donax was sequentially extracted with DMSO, saturated barium hydroxide, and 1.0 M aqueous NaOH solution. The yields of the soluble fractions were 10.2, 6.7, and 10.0% (w/w), respectively, of the dry Arundo donax materials. The DMSO-, Ba(OH)(2)- and NaOH-soluble hemicellulosic fractions were further fractionated into two subfractions by gradient 50% and 80% saturation ammonium sulfate precipitation, respectively. Monosaccharide, molecular weight, FT-IR, and 1D ((1)H and (13)C) and 2D (HSQC) NMR analysis revealed the differences in structural characteristics and physicochemical properties among the subfractions. The subfractions precipitated with 50% saturation ammonium sulfate had lower arabinose/xylose and glucuronic acid/xylose ratios but had higher molecular weight than those of the subfractions precipitated by 80% saturation ammonium sulfate. FT-IR and NMR analysis revealed that the highly acetylated DMSO-soluble hemicellulosic subfraction (H(D50)) could be precipitated with a relatively lower concentration of 50% saturated ammonium sulfate, and thus the gradient ammonium sulfate precipitation technique could discriminate acetyl and non-acetyl hemicelluloses. It was found that the DMSO-soluble subfraction H(D50) precipitated by 50% saturated ammonium sulfate mainly consisted of poorly substituted O-acetyl arabino-4-O-methylglucurono xylan with terminal units of arabinose linked on position 3 of xylose, 4-O-methylglucuronic acid residues linked on position 2 of the xylan bone, and the acetyl groups (degree of acetylation, 37%) linked on position 2 or 3. The DMSO-soluble subfraction H(D80) precipitated by 80% saturated ammonium sulfate was mainly composed of highly substituted arabino-4-O-methylglucurono xylan and β-d-glucan.

Classical non-homologous end-joining pathway utilizes nascent RNA for error-free double-strand break repair of transcribed genes

PubMed Central

Chakraborty, Anirban; Tapryal, Nisha; Venkova, Tatiana; Horikoshi, Nobuo; Pandita, Raj K.; Sarker, Altaf H.; Sarkar, Partha S.; Pandita, Tej K.; Hazra, Tapas K.

2016-01-01

DNA double-strand breaks (DSBs) leading to loss of nucleotides in the transcribed region can be lethal. Classical non-homologous end-joining (C-NHEJ) is the dominant pathway for DSB repair (DSBR) in adult mammalian cells. Here we report that during such DSBR, mammalian C-NHEJ proteins form a multiprotein complex with RNA polymerase II and preferentially associate with the transcribed genes after DSB induction. Depletion of C-NHEJ factors significantly abrogates DSBR in transcribed but not in non-transcribed genes. We hypothesized that nascent RNA can serve as a template for restoring the missing sequences, thus allowing error-free DSBR. We indeed found pre-mRNA in the C-NHEJ complex. Finally, when a DSB-containing plasmid with several nucleotides deleted within the E. coli lacZ gene was allowed time to repair in lacZ-expressing mammalian cells, a functional lacZ plasmid could be recovered from control but not C-NHEJ factor-depleted cells, providing important mechanistic insights into C-NHEJ-mediated error-free DSBR of the transcribed genome. PMID:27703167

A NEW CLASS OF NASCENT ECLIPSING BINARIES WITH EXTREME MASS RATIOS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moe, Maxwell; Stefano, Rosanne Di, E-mail: mmoe@cfa.harvard.edu

2015-03-10

Early B-type main-sequence (MS) stars (M {sub 1} ≈ 5-16 M {sub ☉}) with closely orbiting low-mass stellar companions (q = M {sub 2}/M {sub 1} < 0.25) can evolve to produce Type Ia supernovae, low-mass X-ray binaries, and millisecond pulsars. However, the formation mechanism and intrinsic frequency of such close extreme mass-ratio binaries have been debated, especially considering none have hitherto been detected. Utilizing observations of the Large Magellanic Cloud galaxy conducted by the Optical Gravitational Lensing Experiment, we have discovered a new class of eclipsing binaries in which a luminous B-type MS star irradiates a closely orbiting low-massmore » pre-MS companion that has not yet fully formed. The primordial pre-MS companions have large radii and discernibly reflect much of the light they intercept from the B-type MS primaries (ΔI {sub refl} ≈ 0.02-0.14 mag). For the 18 definitive MS + pre-MS eclipsing binaries in our sample with good model fits to the observed light-curves, we measure short orbital periods P = 3.0-8.5 days, young ages τ ≈ 0.6-8 Myr, and small secondary masses M {sub 2} ≈ 0.8-2.4 M {sub ☉} (q ≈ 0.07-0.36). The majority of these nascent eclipsing binaries are still associated with stellar nurseries, e.g., the system with the deepest eclipse ΔI {sub 1} = 2.8 mag and youngest age τ = 0.6 ± 0.4 Myr is embedded in the bright H II region 30 Doradus. After correcting for selection effects, we find that (2.0 ± 0.6)% of B-type MS stars have companions with short orbital periods P = 3.0-8.5 days and extreme mass ratios q ≈ 0.06-0.25. This is ≈10 times greater than that observed for solar-type MS primaries. We discuss how these new eclipsing binaries provide invaluable insights, diagnostics, and challenges for the formation and evolution of stars, binaries, and H II regions.« less

Safety evaluation of long term oral treatment of methanol sub-fraction of the seeds of Carica papaya as a male contraceptive in albino rats.

PubMed

Goyal, S; Manivannan, B; Ansari, A S; Jain, S C; Lohiya, N K

2010-02-03

The manuscript is one of the series of attempts in authenticating scientific documentation of the seeds of Carica papaya being traditionally used for contraception. To establish safety of the methanol sub-fraction (MSF) of the seeds of Carica papaya as a male contraceptive following long term oral treatment. MSF was administered orally to albino rats at multiples of contraceptive dose (CD) at 50 (1x), 100 (2x), 250 (5x) and 500 (10x)mg/kg body weight daily for 52 weeks. Body weight, organs weight, morbidity, mortality, clinical chemistry, sperm analysis, histopathology and serum testosterone were evaluated to assess the safety and contraceptive efficacy. MSF treatment at various dose regimens, daily for 52 weeks did not show significant changes in body weight, organs weight, food and water intake and pre-terminal deaths compared to those of control animals. Sperm count and viability in 50mg/kg body weight treated animals and the weight of epididymis, seminal vesicle and prostate of all the treated animals showed significant reduction compared to control. Cauda epididymal spermatozoa of 50mg/kg body weight treated animals were immotile. Azoospermia was observed in 100, 250 and 500 mg/kg body weight treated animals. Serum clinical parameters, serum testosterone and histopathology of vital organs were comparable to those of control animals. Histology of testis revealed adverse effects on the process of spermatogenesis, while the histology of epididymis, seminal vesicles and ventral prostate showed no changes compared to control. The long term daily oral administration of MSF affects sperm parameters without adverse side effects and is clinically safe as a male contraceptive. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Residency of rhenium and osmium in a heavy crude oil

NASA Astrophysics Data System (ADS)

DiMarzio, Jenna M.; Georgiev, Svetoslav V.; Stein, Holly J.; Hannah, Judith L.

2018-01-01

Rhenium-osmium (Re-Os) isotope geochemistry is an emerging tool for the study of oil formation and migration processes, and a new technology for petroleum exploration. Little is known, however, about the residency of Re and Os within asphaltene and maltene sub-fractions of crude oil. This information is crucial for understanding the 187Re-187Os radiometric clock held in petroleum systems and for interpreting geochronology for key processes such as oil formation, migration, and biodegradation. In this study, a heavy crude oil was separated into soluble (maltene, MALT) and insoluble (asphaltene, ASPH) fractions using n-heptane as the asphaltene-precipitating agent. The asphaltenes were separated sequentially into sub-fractions using two different solvent pairs (heptane-dichloromethane and acetone-toluene), and the bulk maltenes were separated into saturate, aromatic, and resin (SAR) fractions using open column chromatography. Each asphaltene and maltene sub-fraction was analyzed for Re and Os. The asphaltene sub-fractions and the bulk ASPH, MALT, and crude oil were analyzed for a suite of trace metals by ICP-MS. Our results show that Re and Os concentrations co-vary between the asphaltene sub-fractions, and that both elements are found mostly in the more polar and aromatic sub-fractions. Significant Re and Os are also present in the aromatic and resin fractions of the maltenes. However, each asphaltene and maltene sub-fraction has a distinct isotopic composition, and sub-fractions are not isochronous. This suggests that asphaltene sub-fractionation separates Re-Os complexes to the point where the isotopic integrity of the geochronometer is compromised. The mobility of individual Re and Os isotopes and the decoupling possibilities between radiogenic 187Os produced from 187Re remain elusive, but their recognition in this study is a critical first step. Re and Os correlate strongly with Mo and Cd in the asphaltene sub-fractions, suggesting that these metals occupy

Amino acid levels in nascent metabolic syndrome: A contributor to the pro-inflammatory burden.

PubMed

Reddy, Priya; Leong, Joseph; Jialal, Ishwarlal

2018-05-01

Metabolic Syndrome (MetS) is a cluster of cardio-metabolic risk factors characterized by low-grade inflammation which confers an increased risk for type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). Prior studies have linked elevated branched chain amino acids (BCAA) and aromatic amino acids (AAA) with T2DM and CVD. Due to the paucity of data in MetS, the aim of this study was to investigate the status of amino acids as early biomarkers of nascent MetS patients without T2DM and CVD or smoking. Healthy controls (n = 20) and MetS (n = 29) patients were recruited for the study. MetS was defined by criteria of National Cholesterol Education Program Adult Treatment Panel III of having at least 3 risk factors. Urinary amino acids were quantified by gas chromatography time-of-flight mass spectrometry at the Western NIH Metabolomics Center as expressed to urinary creatinine. Tyrosine and Isoleucine levels were significantly elevated in MetS patients. Isoleucine positively correlated with salient cardio-metabolic features and inflammatory biomarkers. Lysine and Methionine levels were decreased in MetS patients. Lysine correlated negatively with cardio-metabolic features and inflammatory bimarkers. Methionine also correlated negatively with blood pressure and certain inflammatory biomarkers. Our novel results suggest that with regards to the cardio-metabolic risk factors and pro-inflammatory features of MetS, isoleucine (BCAA) demonstrated a positive correlation while lysine demonstrated a negative correlation. Thus, increased levels of isoleucine and decreased levels of lysine could be potential early biomarkers of MetS. Copyright © 2018. Published by Elsevier Inc.

Nascent chain-monitored remodeling of the Sec machinery for salinity adaptation of marine bacteria

PubMed Central

Ishii, Eiji; Chiba, Shinobu; Hashimoto, Narimasa; Kojima, Seiji; Homma, Michio; Ito, Koreaki; Akiyama, Yoshinori; Mori, Hiroyuki

2015-01-01

SecDF interacts with the SecYEG translocon in bacteria and enhances protein export in a proton-motive-force-dependent manner. Vibrio alginolyticus, a marine-estuarine bacterium, contains two SecDF paralogs, V.SecDF1 and V.SecDF2. Here, we show that the export-enhancing function of V.SecDF1 requires Na+ instead of H+, whereas V.SecDF2 is Na+-independent, presumably requiring H+. In accord with the cation-preference difference, V.SecDF2 was only expressed under limited Na+ concentrations whereas V.SecDF1 was constitutive. However, it is not the decreased concentration of Na+ per se that the bacterium senses to up-regulate the V.SecDF2 expression, because marked up-regulation of the V.SecDF2 synthesis was observed irrespective of Na+ concentrations under certain genetic/physiological conditions: (i) when the secDF1VA gene was deleted and (ii) whenever the Sec export machinery was inhibited. VemP (Vibrio export monitoring polypeptide), a secretory polypeptide encoded by the upstream ORF of secDF2VA, plays the primary role in this regulation by undergoing regulated translational elongation arrest, which leads to unfolding of the Shine–Dalgarno sequence for translation of secDF2VA. Genetic analysis of V. alginolyticus established that the VemP-mediated regulation of SecDF2 is essential for the survival of this marine bacterium in low-salinity environments. These results reveal that a class of marine bacteria exploits nascent-chain ribosome interactions to optimize their protein export pathways to propagate efficiently under different ionic environments that they face in their life cycles. PMID:26392525

Curriculum evaluation and revision in a nascent field: the utility of the retrospective pretest--posttest model in a homeland security program of study.

PubMed

Pelfrey, William V; Pelfrey, William V

2009-02-01

Although most academic disciplines evolve at a measured pace, the emerging field of homeland security must, for reasons of safety and security, evolve rapidly. The Department of Homeland Security sponsored the establishment of a graduate educational program for key officials holding homeland security roles. Because homeland security is a nascent field, the establishment of a program curriculum was forced to draw from a variety of disciplines. Curriculum evaluation was complicated by the rapid changes occurring in the emerging discipline, producing response shift bias, and interfering with the pre-post assessments. To compensate for the validity threat associated with response shift bias, a retrospective pretest-posttest evaluative methodology was used. Data indicate the program has evolved in a significant and orderly fashion and these data support the use of this innovative evaluation approach in the development of any discipline.

Cyclin Kinase-independent role of p21CDKN1A in the promotion of nascent DNA elongation in unstressed cells

PubMed Central

Mansilla, Sabrina F; Bertolin, Agustina P; Bergoglio, Valérie; Pillaire, Marie-Jeanne; González Besteiro, Marina A; Luzzani, Carlos; Miriuka, Santiago G; Hoffmann, Jean-Sébastien; Gottifredi, Vanesa

2016-01-01

The levels of the cyclin-dependent kinase (CDK) inhibitor p21 are low in S phase and insufficient to inhibit CDKs. We show here that endogenous p21, instead of being residual, it is functional and necessary to preserve the genomic stability of unstressed cells. p21depletion slows down nascent DNA elongation, triggers permanent replication defects and promotes the instability of hard-to-replicate genomic regions, namely common fragile sites (CFS). The p21’s PCNA interacting region (PIR), and not its CDK binding domain, is needed to prevent the replication defects and the genomic instability caused by p21 depletion. The alternative polymerase kappa is accountable for such defects as they were not observed after simultaneous depletion of both p21 and polymerase kappa. Hence, in CDK-independent manner, endogenous p21 prevents a type of genomic instability which is not triggered by endogenous DNA lesions but by a dysregulation in the DNA polymerase choice during genomic DNA synthesis. DOI: http://dx.doi.org/10.7554/eLife.18020.001 PMID:27740454

A combined crossed-beam and theoretical study of the reaction dynamics of O(3P) + C2H3 → C2H2 + OH: Analysis of the nascent OH products with the preferential population of the Π(A') component

NASA Astrophysics Data System (ADS)

Park, Min-Jin; Jang, Su-Chan; Choi, Jong-Ho

2012-11-01

The gas-phase reaction dynamics of ground-state atomic oxygen [O(3P) from the photo-dissociation of NO2] with vinyl radicals [C2H3 from the supersonic flash pyrolysis of vinyl iodide, C2H3I] has been investigated using a combination of high-resolution laser-induced fluorescence spectroscopy in a crossed-beam configuration and ab initio calculations. Unlike the previous gas-phase bulk kinetic experiments by Baulch et al. [J. Phys. Chem. Ref. Data 34, 757 (2005)], 10.1063/1.1748524, a new exothermic channel of O(3P) + C2H3 → C2H2 + OH (X 2Π: υ″ = 0) has been identified for the first time, and the population analysis shows bimodal nascent rotational distributions of OH products with low- and high-N″ components with a ratio of 2.4:1. No spin-orbit propensities were observed, and the averaged ratios of Π(A')/Π(A″) were determined to be 1.66 ± 0.27. On the basis of computations at the CBS-QB3 theory level and comparison with prior theory, the microscopic mechanisms responsible for the nascent populations can be understood in terms of two competing dynamical pathways: a direct abstraction process in the low-N″ regime as the major pathway and an addition-complex forming process in the high-N″ regime as the minor pathway. Particularly, during the bond cleavage process of the weakly bound van der Waals complex C2H2—OH, the characteristic pathway from the low dihedral-angle geometry was consistent with the observed preferential population of the Π(A') component in the nascent OH products. A molecular-level discussion of the reactivity, mechanism, and dynamical features of the title reaction are presented together with a comparison to gas-phase oxidation reactions of a series of prototypical hydrocarbon radicals.

A combined crossed-beam and theoretical study of the reaction dynamics of O(3P) + C2H3 → C2H2 + OH: analysis of the nascent OH products with the preferential population of the Π(A') component.

PubMed

Park, Min-Jin; Jang, Su-Chan; Choi, Jong-Ho

2012-11-28

The gas-phase reaction dynamics of ground-state atomic oxygen [O((3)P) from the photo-dissociation of NO(2)] with vinyl radicals [C(2)H(3) from the supersonic flash pyrolysis of vinyl iodide, C(2)H(3)I] has been investigated using a combination of high-resolution laser-induced fluorescence spectroscopy in a crossed-beam configuration and ab initio calculations. Unlike the previous gas-phase bulk kinetic experiments by Baulch et al. [J. Phys. Chem. Ref. Data 34, 757 (2005)], a new exothermic channel of O((3)P) + C(2)H(3) → C(2)H(2) + OH (X (2)Π: υ" = 0) has been identified for the first time, and the population analysis shows bimodal nascent rotational distributions of OH products with low- and high-N" components with a ratio of 2.4:1. No spin-orbit propensities were observed, and the averaged ratios of Π(A('))∕Π(A") were determined to be 1.66 ± 0.27. On the basis of computations at the CBS-QB3 theory level and comparison with prior theory, the microscopic mechanisms responsible for the nascent populations can be understood in terms of two competing dynamical pathways: a direct abstraction process in the low-N" regime as the major pathway and an addition-complex forming process in the high-N" regime as the minor pathway. Particularly, during the bond cleavage process of the weakly bound van der Waals complex C(2)H(2)-OH, the characteristic pathway from the low dihedral-angle geometry was consistent with the observed preferential population of the Π(A') component in the nascent OH products. A molecular-level discussion of the reactivity, mechanism, and dynamical features of the title reaction are presented together with a comparison to gas-phase oxidation reactions of a series of prototypical hydrocarbon radicals.

Toward a better understanding of the mechanisms of symbiosis: a comprehensive proteome map of a nascent insect symbiont.

PubMed

Renoz, François; Champagne, Antoine; Degand, Hervé; Faber, Anne-Marie; Morsomme, Pierre; Foray, Vincent; Hance, Thierry

2017-01-01

Symbiotic bacteria are common in insects and can affect various aspects of their hosts' biology. Although the effects of insect symbionts have been clarified for various insect symbiosis models, due to the difficulty of cultivating them in vitro , there is still limited knowledge available on the molecular features that drive symbiosis. Serratia symbiotica is one of the most common symbionts found in aphids. The recent findings of free-living strains that are considered as nascent partners of aphids provide the opportunity to examine the molecular mechanisms that a symbiont can deploy at the early stages of the symbiosis (i.e., symbiotic factors). In this work, a proteomic approach was used to establish a comprehensive proteome map of the free-living S. symbiotica strain CWBI-2.3 T . Most of the 720 proteins identified are related to housekeeping or primary metabolism. Of these, 76 were identified as candidate proteins possibly promoting host colonization. Our results provide strong evidence that S. symbiotica CWBI-2.3 T is well-armed for invading insect host tissues, and suggest that certain molecular features usually harbored by pathogenic bacteria are no longer present. This comprehensive proteome map provides a series of candidate genes for further studies to understand the molecular cross-talk between insects and symbiotic bacteria.

Periplasmic orientation of nascent lipid A in the inner membrane of an Escherichia coli LptA mutant

PubMed Central

Ma, Bing; Reynolds, C. Michael; Raetz, Christian R. H.

2008-01-01

The core-lipid A domain of Escherichia coli lipopolysaccharide (LPS) is synthesized on the inner surface of the inner membrane (IM) and flipped to its outer surface by the ABC transporter MsbA. Recent studies with deletion mutants implicate the periplasmic protein LptA, the cytosolic protein LptB, and the IM proteins LptC, LptF, and LptG in the subsequent transport of nascent LPS to the outer membrane (OM), where the LptD/LptE complex flips LPS to the outer surface. We have isolated a temperature-sensitive mutant (MB1) harboring the S22C and Q111P substitutions in LptA. MB1 stops growing after 30 min at 42°C. 32Pi and [35S]methionine labeling show that export of newly synthesized phospholipids and proteins is not severely impaired, but export of LPS is defective. Using the lipid A 1-phosphatase LpxE as a periplasmic IM marker and the lipid A 3-O-deacylase PagL as an OM marker, we show that core-lipid A reaches the periplasmic side of the IM at 42°C in MB1 but not the outer surface of the OM. Electron microscopy of MB1 reveals dense periplasmic material and a smooth OM at 42°C, consistent with a role for LptA in shuttling LPS across the periplasm. PMID:18768814

Periplasmic orientation of nascent lipid A in the inner membrane of an Escherichia coli LptA mutant.

PubMed

Ma, Bing; Reynolds, C Michael; Raetz, Christian R H

2008-09-16

The core-lipid A domain of Escherichia coli lipopolysaccharide (LPS) is synthesized on the inner surface of the inner membrane (IM) and flipped to its outer surface by the ABC transporter MsbA. Recent studies with deletion mutants implicate the periplasmic protein LptA, the cytosolic protein LptB, and the IM proteins LptC, LptF, and LptG in the subsequent transport of nascent LPS to the outer membrane (OM), where the LptD/LptE complex flips LPS to the outer surface. We have isolated a temperature-sensitive mutant (MB1) harboring the S22C and Q111P substitutions in LptA. MB1 stops growing after 30 min at 42 degrees C. (32)P(i) and [(35)S]methionine labeling show that export of newly synthesized phospholipids and proteins is not severely impaired, but export of LPS is defective. Using the lipid A 1-phosphatase LpxE as a periplasmic IM marker and the lipid A 3-O-deacylase PagL as an OM marker, we show that core-lipid A reaches the periplasmic side of the IM at 42 degrees C in MB1 but not the outer surface of the OM. Electron microscopy of MB1 reveals dense periplasmic material and a smooth OM at 42 degrees C, consistent with a role for LptA in shuttling LPS across the periplasm.

Time-resolved diode laser infrared absorption spectroscopy of the nascent HCl in the infrared laser chemistry of 1,2-dichloro-1,1-difluoroethane

NASA Astrophysics Data System (ADS)

Dietrich, Peter; Quack, Martin; Seyfang, George

1990-04-01

The IR multiphoton excitation and the frequency, fluence and intensity dependence of the IR-laser chemical yields of CF 2ClCH 2Cl have been studied in the fluence range of 1 to 10 J cm -2 yielding a steady-state constant k(st)/ I=0.74×10 6 s -1 MW -1 cm 2 which is approximately independent of intensity. Time-resolved IR absorption spectroscopy with diode laser sources has been used to observe the nascent HCl during the first few 100 ns indicating a population inversion between the levels ν=1, J=4 and ν=2, J=5. At low reactant pressures ( p⩽10 Pa) the time-resolved measurement gives a steady-state rate constant consistent with the theoretical result adjusted to the static yield measurements. The capability of state-selective and time-resolved IR spectroscopy is thus demonstrated, giving real-time determinations of rate constants.

Long-term high-soybean oil feeding alters regulation of body temperature in rats.

PubMed

Tsushima, Hiromi; Yamada, Kazuyo; Miyazawa, Daisuke; Mori, Mayumi; Hashimoto, Yoko; Ohkubo, Takeshi; Hibino, Hidehiko; Okuyama, Harumi

2014-01-01

We investigated whether body temperature (BT) regulatory mechanisms are influenced by dietary fatty acids (FA). Male Wistar rats were fed a high-fat diet containing fish oil (HFD), soybean oil (HSD) or lard (HLD). At the 20-week intervention, the BT of the HSD and HLD groups were lower than that of the normal diet (ND) group in the light and dark periods. The intracerebroventricular injections of interleukin-1β and bombesin in the HSD group induced greater hyperthermia and weaker hypothermia, respectively, than in the ND group. The HSD differentially affected BT under both physiological and pharmacological conditions. In the hypothalamus, the ratio of n-6/n-3 FAs was higher in the HSD group compared with the ND group. DNA microarrays revealed increased expression of thyroid-stimulating hormone β-subunit, and decreased expression of several genes in the hypothalamus of the HSD group compared with the ND group. The HSD feeding increased several adipokine concentrations in the plasma. However, there were no adipokines or gene expressions that changed in only the HSD and HLD groups showing significant hypothermia under the physiological condition. These findings suggested that long-term HSD intake produces abnormal BT regulation. It is less likely that adipokines or proteins/peptides are involved in abnormal BT regulation under the physiological conditions after HSD feeding.

Cytotoxic Compounds from Aerial Organs of Xanthium strumarium.

PubMed

Ferrer, Janet Piloto; Zampini, Iris Catiana; Cuello, Ana Soledad; Francisco, Marbelis; Romero, Aylema; Valdivia, Dayana; Gonzalez, Maria; Carlos Salas; Lamar, Angel Sanchez; Isla, Maria Inés

2016-03-01

Xanthium strumarium L., the main species of the genus Xanthium, is ubiquitously distributed. The aim of this study was to determine the cytotoxic effect of aerial organs of X strumarium, grown in Cuba, against cancer cell lines and the isolation of compounds potentially responsible for this activity. Initially, an ethanol partitioning procedure yielded the XSE extract that was subsequently fractionated with chloroform resulting in a XSCF fraction. Both, XSE and XSCF fractions exhibited cytotoxic effects on MDA MB-23 1, MCF7, A549 and CT26 cell lines by using the MTT assay. Above all, the XSCF fraction was more active than XSE. For this reason, XSCF was subsequently fractionated by silica gel chromatography and the active fractions submitted to semi-preparative HPLC for isolation of bioactive compounds. Six sub-fractions (SF1 to SF6) were recovered. Sub-fractions 3 and 6 were the most active on each assayed cell line, while sub-fractions 4 and 5 were only active against A549 and CT26 cell lines. In each case, sub-fraction 6 showed the strongest inhibitory effect. The HPLC-DAD fingerprint of sub-fraction 6 showed a single peak that was identified by GC-MS as (-) spathulenol, a sesquiterpene with reported antitumor activity.

Long-Peptide Cross-Presentation by Human Dendritic Cells Occurs in Vacuoles by Peptide Exchange on Nascent MHC Class I Molecules.

PubMed

Ma, Wenbin; Zhang, Yi; Vigneron, Nathalie; Stroobant, Vincent; Thielemans, Kris; van der Bruggen, Pierre; Van den Eynde, Benoît J

2016-02-15

Cross-presentation enables dendritic cells to present on their MHC class I molecules antigenic peptides derived from exogenous material, through a mechanism that remains partly unclear. It is particularly efficient with long peptides, which are used in cancer vaccines. We studied the mechanism of long-peptide cross-presentation using human dendritic cells and specific CTL clones against melanoma Ags gp100 and Melan-A/MART1. We found that cross-presentation of those long peptides does not depend on the proteasome or the transporter associated with Ag processing, and therefore follows a vacuolar pathway. We also observed that it makes use of newly synthesized MHC class I molecules, through peptide exchange in vesicles distinct from the endoplasmic reticulum and classical secretory pathway, in an SEC22b- and CD74-independent manner. Our results indicate a nonclassical secretion pathway followed by nascent HLA-I molecules that are used for cross-presentation of those long melanoma peptides in the vacuolar pathway. Our results may have implications for the development of vaccines based on long peptides. Copyright © 2016 by The American Association of Immunologists, Inc.

Endurance exercise training effects on body fatness, VO2max, HDL-C subfractions, and glucose tolerance are influenced by a PLIN haplotype in older Caucasians.

PubMed

Jenkins, Nathan T; McKenzie, Jennifer A; Damcott, Coleen M; Witkowski, Sarah; Hagberg, James M

2010-03-01

Perilipins are lipid droplet-coating proteins that regulate intracellular lipolysis in adipocytes. A haplotype of two perilipin gene (PLIN) single nucleotide polymorphisms, 13041A>G and 14995A>T, has been previously associated with obesity risk. Furthermore, the available data indicate that this association may be modified by sex. We hypothesized that this haplotype would associate with body fatness, aerobic fitness, and a number of cardiovascular (CV) risk factor phenotypes before and after a 6-mo endurance exercise training program in sedentary older Caucasians. The major haplotype group (13041A/14995A; n = 57) had significantly lower body mass index (BMI) and body fatness compared with noncarriers of the AA haplotype (n = 44) before the training intervention. Training improved body composition in both groups, but fatness remained higher in noncarriers than AA carriers after training. This fat retention in noncarriers blunted their maximal oxygen uptake (Vo(2 max)) adaptation to training. Female noncarriers had substantially higher concentrations of several conventionally and NMR-measured HDL-C subfractions than male noncarriers before and after training, but only minimal differences were found between the sexes in the AA haplotype group. Haplotype group differences in baseline and after-training responses to an oral glucose tolerance test (OGTT) also differed by sex, as noncarrier men had the highest baseline area under the insulin curve (insulin AUC), but were the only group to significantly improve insulin AUC with training. The insulin sensitivity index and plasma glucose responses to the OGTT were more favorable in AA carriers than noncarriers before and after training. Overall, our findings suggest that PLIN variation explains some of the interindividual differences in the response of obesity and CV phenotypes to exercise training. Furthermore, these data contribute to the growing understanding of PLIN as a candidate gene for human obesity and the

Activity of tannins from Stryphnodendron adstringens on Cryptococcus neoformans: effects on growth, capsule size and pigmentation

PubMed Central

Ishida, Kelly; Rozental, Sonia; de Mello, João Carlos Palazzo; Nakamura, Celso Vataru

2009-01-01

Background Stryphnodendron adstringens (Mart.) Coville, Leguminosae, also known in Brazil as barbatimão, is rich in tannins and many flavan-3-ols and proanthocyanidins such as prodelphinidins and prorobinetinidins. Previous studies have demonstrated several pharmacological properties of tannins from barbatimão, including anti-candidal activity. Methods The antifungal activity of proanthocyanidin polymeric tannins from Stryphnodendron adstringens (subfraction F2.4) was evaluated against three strains of Cryptococcus neoformans with different capsule expressions, using the broth microdilution technique, light microscopy and transmission electron microscopy. The effect of subfraction F2.4 on C. neoformans and melanoma mammalian cells pigmentation was also evaluated. Results Although susceptibility assays revealed MIC values quite similar (between 2.5 and 5.0 μg/ml), analyses of MFC values revealing that the acapsular mutant Cap 67 was more susceptible to be killed by the subfraction F2.4 (MFC = 20 μg/ml) than the two tested capsular strains (T1-444 and ATCC 28957) (MFC > 160 μg/ml). Optical and electron microscopy experiments revealed relevant alterations in cell shape and size in all strains treated with 1 and 2.5 μg/ml of subfraction F2.4. Capsule size of the capsular strains decreased drastically after subfraction F2.4 treatment. In addition, ultrastructural alterations such as cell wall disruption, cytoplasm extraction, mitochondria swelling, increase in the number of cytoplasmic vacuoles and formation of membranous structures in the cytoplasm were also observed in treated yeasts. Incubation with subfraction F2.4 also decreased C. neoformans pigmentation, however, did not interfere in melanization of B16F10 mammalian cells. Conclusion Our data indicate that tannins extracted from S. adstringens interfered with growth, capsule size and pigmentation, all important virulence factors of C. neoformans, and may be considered as a putative candidate for the

Effects of low-dose monophasic levonorgestrel with ethinyl estradiol preparation on serum lipid levels: A twenty-four month clinical trial.

PubMed

Young, R L; DelConte, A

1999-11-01

The aim of this 24-cycle study was to evaluate the effects on serum lipid concentrations of an oral contraceptive preparation containing 100 microg levonorgestrel and 20 microg ethinyl estradiol. Forty-two healthy women were enrolled in a study designed to evaluate the effects on serum lipid concentrations of an oral contraceptive containing 100 microg levonorgestrel and 20 microg ethinyl estradiol. Lipid data were evaluated for 28 women who completed 24 cycles of treatment with a preparation of 100 microg levonorgestrel with 20 microg ethinyl estradiol for 21 days followed by placebo for 7 days. Concentrations of triglycerides, total cholesterol, high-density lipoprotein cholesterol, high-density lipoprotein cholesterol subfractions 2 and 3, low-density lipoprotein cholesterol, and apolipoproteins A-I and B were analyzed. Mean percentage changes from baseline were tested for significance by means of paired Student t tests. Total cholesterol, high-density lipoprotein cholesterol, high-density lipoprotein subfraction 2, and apolipoprotein A-I concentrations were not significantly changed from baseline. Neither was the ratio of high-density lipoprotein subfraction 2 to high-density lipoprotein subfraction 3. Mean percentage increases in concentrations of triglyceride, high-density lipoprotein subfraction 3, apolipoprotein B, and low-density lipoprotein cholesterol and increases in the ratios of total cholesterol to high-density lipoprotein cholesterol, low-density lipoprotein cholesterol to high-density lipoprotein cholesterol, and apolipoprotein B to apolipoprotein A-I were significant (P <.05) at >/=1 cycle. By cycle 24, however, only the concentration of high-density lipoprotein subfraction 3 remained significantly elevated. Changes in the plasma lipid profiles among women receiving monophasic 100 microg levonorgestrel with 20 microg ethinyl estradiol were similar to those seen with other low-dose oral contraceptives, but by cycle 24 only 1 of 7 mean values

Activity of tannins from Stryphnodendron adstringens on Cryptococcus neoformans: effects on growth, capsule size and pigmentation.

PubMed

Ishida, Kelly; Rozental, Sonia; de Mello, João Carlos Palazzo; Nakamura, Celso Vataru

2009-11-05

Stryphnodendron adstringens (Mart.) Coville, Leguminosae, also known in Brazil as barbatimão, is rich in tannins and many flavan-3-ols and proanthocyanidins such as prodelphinidins and prorobinetinidins. Previous studies have demonstrated several pharmacological properties of tannins from barbatimão, including anti-candidal activity. The antifungal activity of proanthocyanidin polymeric tannins from Stryphnodendron adstringens (subfraction F2.4) was evaluated against three strains of Cryptococcus neoformans with different capsule expressions, using the broth microdilution technique, light microscopy and transmission electron microscopy. The effect of subfraction F2.4 on C. neoformans and melanoma mammalian cells pigmentation was also evaluated. Although susceptibility assays revealed MIC values quite similar (between 2.5 and 5.0 microg/ml), analyses of MFC values revealing that the acapsular mutant Cap 67 was more susceptible to be killed by the subfraction F2.4 (MFC = 20 microg/ml) than the two tested capsular strains (T1-444 and ATCC 28957) (MFC > 160 microg/ml). Optical and electron microscopy experiments revealed relevant alterations in cell shape and size in all strains treated with 1 and 2.5 microg/ml of subfraction F2.4. Capsule size of the capsular strains decreased drastically after subfraction F2.4 treatment. In addition, ultrastructural alterations such as cell wall disruption, cytoplasm extraction, mitochondria swelling, increase in the number of cytoplasmic vacuoles and formation of membranous structures in the cytoplasm were also observed in treated yeasts. Incubation with subfraction F2.4 also decreased C. neoformans pigmentation, however, did not interfere in melanization of B16F10 mammalian cells. Our data indicate that tannins extracted from S. adstringens interfered with growth, capsule size and pigmentation, all important virulence factors of C. neoformans, and may be considered as a putative candidate for the development of new antifungal

Tannins and terpenoids as major precursors of Suwannee River fulvic acid

USGS Publications Warehouse

Leenheer, Jerry A.; Rostad, Colleen E.

2004-01-01

Suwannee River fulvic acid (SRFA) was fractionated into 7 fractions by normal-phase chromatography on silica gel followed by reverse-phase fractionation on XAD-8 resin that produced 18 subfractions. Selected major subfractions were characterized by 13C-nuclear magnetic resonance (NMR), infrared spectrometry, and elemental analyses. 13C-NMR spectra of the subfractions were more indicative of precursor structures than unfractionated SRFA, and gave spectral profiles that indicated SRFA mass was about equally split between tannin precursors and terpenoid precursors. Lignin precursors were minor components. Synthesis of 13C-NMR data with elemental data for subfractions derived from both tannin and terpenoid precursors revealed high ring contents and low numbers of carbon per rings which is indicative of fused ring structures that are extensively substituted with carboxyl and methyl groups. These results ruled out extended chain structures for SRFA. This information is useful for determining sources and properties of fulvic acid in drinking water supplies as tannins are more reactive with chlorine to produce undesirable disinfection by-products than are terpenoids.

Structural characterization of phenolic compounds and antioxidant activity of the phenolic-rich fraction from defatted adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) seed meal.

PubMed

Wang, Lifeng; Chen, Chao; Su, Anxiang; Zhang, Yiyi; Yuan, Jian; Ju, Xingrong

2016-04-01

The current study aims to investigate the antioxidant activities of various extracts from defatted adlay seed meal (DASM) based on the oxygen radical absorbance capacity (ORAC) assay, peroxyl radical scavenging capacity (PSC) assay and cellular antioxidant activity (CAA) assay. Of all the fractions, the n-butanol fraction exhibited the highest antioxidant activity, followed by crude acetone extract and aqueous fractions. Of the three sub-fractions obtained by Sephadex LH-20 chromatography, sub-fraction 3 possessed the highest antioxidant activity and total phenolic content. There was a strong positive correlation between the total phenolic content and the antioxidant activity. Based on HPLC-DAD-ESI-MS/MS analysis, the most abundant phenolic acid in sub-fraction 3 of DASM was ferulic acid at 67.28 mg/g, whereas the predominant flavonoid was rutin at 41.11 mg/g. Of the major individual compounds in sub-fraction 3, p-coumaric acid exhibited the highest ORAC values, and quercetin exhibited the highest PSC values and CAA values. Copyright © 2015 Elsevier Ltd. All rights reserved.

Endurance exercise training effects on body fatness, V̇o2max, HDL-C subfractions, and glucose tolerance are influenced by a PLIN haplotype in older Caucasians

PubMed Central

Jenkins, Nathan T.; McKenzie, Jennifer A.; Damcott, Coleen M.; Witkowski, Sarah

2010-01-01

Perilipins are lipid droplet-coating proteins that regulate intracellular lipolysis in adipocytes. A haplotype of two perilipin gene (PLIN) single nucleotide polymorphisms, 13041A>G and 14995A>T, has been previously associated with obesity risk. Furthermore, the available data indicate that this association may be modified by sex. We hypothesized that this haplotype would associate with body fatness, aerobic fitness, and a number of cardiovascular (CV) risk factor phenotypes before and after a 6-mo endurance exercise training program in sedentary older Caucasians. The major haplotype group (13041A/14995A; n = 57) had significantly lower body mass index (BMI) and body fatness compared with noncarriers of the AA haplotype (n = 44) before the training intervention. Training improved body composition in both groups, but fatness remained higher in noncarriers than AA carriers after training. This fat retention in noncarriers blunted their maximal oxygen uptake (V̇o2max) adaptation to training. Female noncarriers had substantially higher concentrations of several conventionally and NMR-measured HDL-C subfractions than male noncarriers before and after training, but only minimal differences were found between the sexes in the AA haplotype group. Haplotype group differences in baseline and after-training responses to an oral glucose tolerance test (OGTT) also differed by sex, as noncarrier men had the highest baseline area under the insulin curve (insulin AUC), but were the only group to significantly improve insulin AUC with training. The insulin sensitivity index and plasma glucose responses to the OGTT were more favorable in AA carriers than noncarriers before and after training. Overall, our findings suggest that PLIN variation explains some of the interindividual differences in the response of obesity and CV phenotypes to exercise training. Furthermore, these data contribute to the growing understanding of PLIN as a candidate gene for human obesity and the

Th1-stimulatory polyproteins of soluble Leishmania donovani promastigotes ranging from 89.9 to 97.1 kDa offers long-lasting protection against experimental visceral leishmaniasis.

PubMed

Kumari, Shraddha; Samant, Mukesh; Misra, Pragya; Khare, Prashant; Sisodia, Brijesh; Shasany, Ajit K; Dube, Anuradha

2008-10-23

Our earlier studies identified a fraction (F2) of Leishmania donovani soluble promastigote antigen belonging to 97.4-68 kDa for its ability to stimulate Th1-type cellular responses in cured visceral leishmaniasis (VL) patients as well as in cured hamsters. A further fractionation of F2-fraction into seven subfractions (F2.1-F2.7) and re-assessment for their immunostimulatory responses revealed that out of these, only four (F2.4-F2.7) belonging to 89.9-97.1 kDa, stimulated remarkable Th1-type cellular responses either individually or in a pooled form (P4-7). In this study these potential subfractions were further assessed for their prophylactic potential in combination with BCG against L. donovani challenge in hamsters. Optimum parasite inhibition ( approximately 99%) was obtained in hamsters vaccinated with pooled subfractions and they survived for 1 year. The protection was further supported by remarkable lymphoproliferative, IFN-gamma and IL-12 responses along with profound delayed type hypersensitivity and increased levels of Leishmania-specific IgG2 antibody as observed on days 45, 90 and 120 post-challenge suggesting that a successful subunit vaccine against VL may require multiple Th1-immunostimulatory proteins. MALDI-TOF-MS/MS analysis of these subfractions further revealed that of the 19 identified immunostimulatory proteins, Elongation factor-2, p45, Heat shock protein-70/83, Aldolase, Enolase, Triosephosphate isomerase, Disulfideisomerase and Calreticulin were the major ones in these subfractions.

The FAK–Arp2/3 interaction promotes leading edge advance and haptosensing by coupling nascent adhesions to lamellipodia actin

PubMed Central

Swaminathan, Vinay; Fischer, R. S.; Waterman, Clare M.

2016-01-01

Cell migration is initiated in response to biochemical or physical cues in the environment that promote actin-mediated lamellipodial protrusion followed by the formation of nascent integrin adhesions (NAs) within the protrusion to drive leading edge advance. Although FAK is known to be required for cell migration through effects on focal adhesions, its role in NA formation and lamellipodial dynamics is unclear. Live-cell microscopy of FAK−/− cells with expression of phosphorylation deficient or a FERM-domain mutant deficient in Arp2/3 binding revealed a requirement for FAK in promoting the dense formation, transient stabilization, and timely turnover of NA within lamellipodia to couple actin-driven protrusion to adhesion and advance of the leading edge. Phosphorylation on Y397 of FAK promotes dense NA formation but is dispensable for transient NA stabilization and leading edge advance. In contrast, transient NA stabilization and advance of the cell edge requires FAK–Arp2/3 interaction, which promotes Arp2/3 localization to NA and reduces FAK activity. Haptosensing of extracellular matrix (ECM) concentration during migration requires the interaction between FAK and Arp2/3, whereas FAK phosphorylation modulates mechanosensing of ECM stiffness during spreading. Taken together, our results show that mechanistically separable functions of FAK in NA are required for cells to distinguish distinct properties of their environment during migration. PMID:26842895

Seismic Imaging of a Nascent Batholith in the Central Andes

NASA Astrophysics Data System (ADS)

Ward, K. M.; Zandt, G.; Beck, S. L.; Christensen, D. H.; Mcfarlin, H. L.

2013-12-01

Cordilleran mountain belts, such as the modern central Andes and Mesozoic western North American Cordillera formed in regions of significant upper plate compression and were punctuated by high flux magmatic events that coalesced into large composite batholiths. Unlike the North American Cordillera, compressive mountain building is still active in the central Andes and any large modern batholith still at depth must be inferred from surface volcanics and geophysical data. In the Andes it has been suggested that a modern batholith exists beneath the Altiplano-Puna Volcanic Complex (APVC), the location of a 11-1 Ma ignimbrite flare-up, however, the magmatic underpinnings has only been geophysically investigated in a few widely spaced locations and a migmatite zone of crustal melt with minimal mantle input remains a viable competing interpretation. We present new high-resolution 3-D seismic images of the APVC crust based on a joint inversion of ambient noise surface-wave dispersion data and receiver functions from broadband stations and identify a shallow (<20 km depth) low-velocity body that we interpret as a magmatic mush zone, the Altiplano-Puna Mush Body (APMB). Below the APMB, we observe near-vertical zones of low velocity that bifurcate near the base of the crust with one arm of low velocity migrating under the main volcanic arc and a second separate arm of low velocity below the voluminous backarc volcanism. Previous attenuation tomography studies have traced these zones through the mantle where they intersect the top of the subducting Nazca slab at locations with elevated seismic activity, providing strong evidence that the deeper near-vertical zones of low velocity we are imaging are related to dewatering of the slab and associated mantle-sourced melt pathways. Based on these considerations, we suggest the ~200 km diameter and ~20 km thick body is a nascent silicic batholith compatible with the magma mush model of batholith formation. The direct imaging of this

Gene-Silencing-Induced Changes in Carbohydrate Conformation in Relation to Bioenergy Value and Carbohydrate Subfractions in Modeled Plant (Medicago sativa) with Down-Regulation of HB12 and TT8 Transcription Factors

PubMed Central

Li, Xinxin; Hannoufa, Abdelali; Zhang, Yonggen; Yu, Peiqiang

2016-01-01

Gene silencing with RNA interference (RNAi) technology may be capable of modifying internal structure at a molecular level. This structural modification could affect biofunctions in terms of biodegradation, biochemical metabolism, and bioactive compound availability. The objectives of this study were to (1) Detect gene silencing-induced changes in carbohydrate molecular structure in an alfalfa forage (Medicago sativa spp. sativa: alfalfa) with down-regulation of genes that encode transcription factors TT8 and HB12; (2) Determine gene silencing-induced changes in nutrient bioutilization and bioavailability in the alfalfa forage (Medicago sativa); and (3) Quantify the correlation between gene silencing-induced molecular structure changes and the nutrient bioutilization and bioavailability in animals of ruminants. The experimental treatments included: T1 = Non-transgenic and no-gene silenced alfalfa forage (code “NT”); T2 = HB12-RNAi forage with HB12 gene down regulation (code “HB12”); T3 = TT8-RNAi forage with TT8 gene down regulation (code “TT8”). The HB12 and TT8 gene silencing-induced molecular structure changes were determined by non-invasive and non-destructive advanced molecular spectroscopy in a middle infrared radiation region that focused on structural, non-structural and total carbohydrate compounds. The nutrient bioutilization and bioavailability of the modified forage were determined using NRC-2001 system in terms of total digestive nutrient (TDN), truly digestible fiber (tdNDF), non-fiber carbohydrate (tdNDF), fatty acid (tdFA), crude protein (tdCP) and bioenergy profiles (digestible energy, metabolizable energy, net energy) for ruminants. The carbohydrate subfractions were evaluated using the updated CNCPS 6.0 system. The results showed that gene silencing significantly affected tdNFC (42.3 (NT) vs. 38.7 (HB12) vs. 37.4% Dry Matter (TT8); p = 0.016) and tdCP (20.8 (NT) vs. 19.4 (HB12) vs. 22.3% DM (TT8); p = 0.009). The gene-silencing also

Gene-Silencing-Induced Changes in Carbohydrate Conformation in Relation to Bioenergy Value and Carbohydrate Subfractions in Modeled Plant (Medicago sativa) with Down-Regulation of HB12 and TT8 Transcription Factors.

PubMed

Li, Xinxin; Hannoufa, Abdelali; Zhang, Yonggen; Yu, Peiqiang

2016-05-13

Gene silencing with RNA interference (RNAi) technology may be capable of modifying internal structure at a molecular level. This structural modification could affect biofunctions in terms of biodegradation, biochemical metabolism, and bioactive compound availability. The objectives of this study were to (1) Detect gene silencing-induced changes in carbohydrate molecular structure in an alfalfa forage (Medicago sativa spp. sativa: alfalfa) with down-regulation of genes that encode transcription factors TT8 and HB12; (2) Determine gene silencing-induced changes in nutrient bioutilization and bioavailability in the alfalfa forage (Medicago sativa); and (3) Quantify the correlation between gene silencing-induced molecular structure changes and the nutrient bioutilization and bioavailability in animals of ruminants. The experimental treatments included: T1 = Non-transgenic and no-gene silenced alfalfa forage (code "NT"); T2 = HB12-RNAi forage with HB12 gene down regulation (code "HB12"); T3 = TT8-RNAi forage with TT8 gene down regulation (code "TT8"). The HB12 and TT8 gene silencing-induced molecular structure changes were determined by non-invasive and non-destructive advanced molecular spectroscopy in a middle infrared radiation region that focused on structural, non-structural and total carbohydrate compounds. The nutrient bioutilization and bioavailability of the modified forage were determined using NRC-2001 system in terms of total digestive nutrient (TDN), truly digestible fiber (tdNDF), non-fiber carbohydrate (tdNDF), fatty acid (tdFA), crude protein (tdCP) and bioenergy profiles (digestible energy, metabolizable energy, net energy) for ruminants. The carbohydrate subfractions were evaluated using the updated CNCPS 6.0 system. The results showed that gene silencing significantly affected tdNFC (42.3 (NT) vs. 38.7 (HB12) vs. 37.4% Dry Matter (TT8); p = 0.016) and tdCP (20.8 (NT) vs. 19.4 (HB12) vs. 22.3% DM (TT8); p = 0.009). The gene-silencing also affected

Conversion of α-linolenic acid to long-chain omega-3 fatty acid derivatives and alterations of HDL density subfractions and plasma lipids with dietary polyunsaturated fatty acids in Monk parrots (Myiopsitta monachus).

PubMed

Petzinger, C; Larner, C; Heatley, J J; Bailey, C A; MacFarlane, R D; Bauer, J E

2014-04-01

The effect of α-linolenic acid from a flaxseed (FLX)-enriched diet on plasma lipid and fatty acid metabolism and possible atherosclerosis risk factors was studied in Monk parrots (Myiopsitta monachus). Twenty-four Monk parrots were randomly assigned to diets containing either 10% ground SUNs or 10% ground FLXs. Feed intake was calculated daily. Blood samples, body condition scores and body weights were obtained at -5 weeks, day 0, 7, 14, 28, 42 and 70. Plasma samples were analysed for total cholesterol, free cholesterol, triacylglycerols and lipoproteins. Phospholipid subfraction fatty acid profiles were determined. By day 70, the FLX group had significantly higher plasma phospholipid fatty acids including 18:3n-3 (α-linolenic acid), 20:5n-3 (eicosapentaenoic acid) and 22:6n-3 (docosahexaenoic acid). The sunflower group had significantly higher plasma phospholipid levels of 20:4n-6 (arachidonic acid). By day 70, the high-density lipoprotein (HDL) peak shifted resulting in significantly different HDL peak densities between the two experimental groups (1.097 g/ml FLX group and 1.095 g/ml SUN group, p = 0.028). The plasma fatty acid results indicate that Monk parrots can readily convert α-linolenic acid to the long-chain omega-3 derivatives including docosahexaenoic acid and reduce 20:4n-6 accumulation in plasma phospholipids. The reason for a shift in the HDL peak density is unknown at this time. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.

Extracts and Fractions from Edible Roots of Sechium edule (Jacq.) Sw. with Antihypertensive Activity

PubMed Central

Lombardo-Earl, Galia; Roman-Ramos, Rubén; Zamilpa, Alejandro; Herrera-Ruiz, Maribel; Rosas-Salgado, Gabriela; Tortoriello, Jaime; Jiménez-Ferrer, Enrique

2014-01-01

Sechium edule is traditionally used in Mexico as a therapeutic resource against renal diseases and to control high blood pressure. The purpose of this work is to evaluate the antihypertensive effect of the hydroalcoholic extract obtained from the roots of this plant, including its fractions and subfractions, on different hypertension models induced with angiotensin II (AG II). The hydroalcoholic extract was tested on an in vitro study of isolated aorta rings denuded of endothelial cells, using AG II as the agonist; this assay proved the vasorelaxant effect of this extract. Vagotomized rats were administered different doses of AG II as well as the Hydroalcoholic extract, which reduced blood pressure in 30 mmHg approximately; subsequently this extract was separated into two fractions (acetone and methanol) which were evaluated in the acute hypertension mouse model induced with AG II, where the acetone fraction was identified as the most effective one and was subsequently subfractioned using an open chromatographic column packed with silica gel. The subfractions were also evaluated in the acute hypertension model. Finally, the extract, fraction, and active subfraction were analyzed by MS-PDA-HPLC, identifying cinnamic derivative compounds like cinnamic acid methyl ester. PMID:24812568

hnRNP-Q1 represses nascent axon growth in cortical neurons by inhibiting Gap-43 mRNA translation

PubMed Central

Williams, Kathryn R.; McAninch, Damian S.; Stefanovic, Snezana; Xing, Lei; Allen, Megan; Li, Wenqi; Feng, Yue; Mihailescu, Mihaela Rita; Bassell, Gary J.

2016-01-01

Posttranscriptional regulation of gene expression by mRNA-binding proteins is critical for neuronal development and function. hnRNP-Q1 is an mRNA-binding protein that regulates mRNA processing events, including translational repression. hnRNP-Q1 is highly expressed in brain tissue, suggesting a function in regulating genes critical for neuronal development. In this study, we have identified Growth-associated protein 43 (Gap-43) mRNA as a novel target of hnRNP-Q1 and have demonstrated that hnRNP-Q1 represses Gap-43 mRNA translation and consequently GAP-43 function. GAP-43 is a neuronal protein that regulates actin dynamics in growth cones and facilitates axonal growth. Previous studies have identified factors that regulate Gap-43 mRNA stability and localization, but it remains unclear whether Gap-43 mRNA translation is also regulated. Our results reveal that hnRNP-Q1 knockdown increased nascent axon length, total neurite length, and neurite number in mouse embryonic cortical neurons and enhanced Neuro2a cell process extension; these phenotypes were rescued by GAP-43 knockdown. Additionally, we have identified a G-quadruplex structure in the 5′ untranslated region of Gap-43 mRNA that directly interacts with hnRNP-Q1 as a means to inhibit Gap-43 mRNA translation. Therefore hnRNP-Q1–mediated repression of Gap-43 mRNA translation provides an additional mechanism for regulating GAP-43 expression and function and may be critical for neuronal development. PMID:26658614

Electron microscopic visualization of sites of nascent DNA synthesis by streptavidin-gold binding to biotinylated nucleotides incorporated in vivo

PubMed Central

1988-01-01

Biotinylated nucleotides (bio-11-dCTP, bio-11-dUTP, and bio-7-dATP) were microinjected into unfertilized and fertilized Xenopus laevis eggs. The amounts introduced were comparable to in vivo deoxy- nucleoside triphosphate pools. At various times after microinjection, DNA was extracted from eggs or embryos and subjected to electrophoresis on agarose gels. Newly synthesized biotinylated DNA was analyzed by Southern transfer and visualized using either the BluGENE or Detek-hrp streptavidin-based nucleic acid detection systems. Quantitation of the amount of biotinylated DNA observed at various times showed that the microinjected biotinylated nucleotides were efficiently incorporated in vivo, both into replicating endogenous chromosomal DNA and into replicating microinjected exogenous plasmid DNA. At least one biotinylated nucleotide could be incorporated in vivo for every eight nucleotides of DNA synthesized. Control experiments also showed that heavily biotinylated DNA was not subjected to detectable DNA repair during early embryogenesis (for at least 5 h after activation of the eggs). The incorporated biotinylated nucleotides were visualized by electron microscopy by using streptavidin-colloidal gold or streptavidin-ferritin conjugates to bind specifically to the biotin groups projecting from the newly replicated DNA. The incorporated biotinylated nucleotides were thus made visible as electron-dense spots on the underlying DNA molecules. Biotinylated nucleotides separated by 20-50 bases could be resolved. We conclude that nascent DNA synthesized in vivo in Xenopus laevis eggs can be visualized efficiently and specifically using the techniques described. PMID:3392102

The influence of repeated administration of poloxamer 407 on serum lipoproteins and protease activity in mouse liver and heart.

PubMed

Korolenko, Tatyana A; Tuzikov, Fedor V; Johnston, Thomas P; Tuzikova, Natalia A; Kisarova, Yana A; Zhanaeva, Svetlana Ya; Alexeenko, Tatyana V; Zhukova, Natalia A; Brak, Ivan V; Spiridonov, Victor K; Filjushina, Elena E; Cherkanova, Marina S; Monoszon, Anna A

2012-11-01

The effects of repeated administration of poloxamer 407 (P-407) on lipoprotein-cholesterol (LP-C) and lipoprotein-triglyceride (LP-TG) fractions and subfractions, as well as the effect on liver and heart proteases, were studied. Repeated administration of P-407 to male CBA mice resulted in a model of atherosclerosis with increased diastolic blood pressure; there was a drastic increase in total serum cholesterol and especially TG. A novel small-angle X-ray scattering method for the determination of the fractional and subfractional composition of LP-C and LP-TG was used. In chronically P-407-treated mice, P-407 significantly increased atherogenic low-density lipoprotein C (LDL-C) fractions, as well as intermediate-density lipoprotein C (IDL-C), and LDL₁₋₃-C subfractions, and very-low-density lipoprotein-C (VLDL-C) fractions, as well as VLDL₁₋₂-C and VLDL₃₋₅-C subfractions), to a lesser extent, the total anti-atherogenic high-density lipoprotein C (HDL-C) fraction, as well as HDL₂-C and HDL₃-C subfractions. Additionally, we demonstrated an increase in the serum chitotriosidase activity, without significant changes in serum matrix metalloprotease (MMP) activity. Morphological changes observed in P-407-treated mice included atherosclerosis in the heart and storage syndrome in the liver macrophages. P-407 significantly increased the activity of cysteine, aspartate proteases, and MMPs in the heart, and only the activity of cathepsin B and MMPs in the liver of mice. Thus, repeated administration of P-407 to mice induced atherosclerosis secondary to sustained dyslipidemia and formation of foamy macrophages in liver, and also modulated the activity of heart and liver proteases.

A bioactivity guided study on the antibacterial activity of Hertia cheirifolia L. extracts.

PubMed

Majouli, Kaouther; Hamdi, Assia; Msaada, Kamel; Kenani, Abderraouf

2017-05-01

This study was carried out with the objective to investigate the antibacterial activity of Hertia cheirifolia L. extracts against Gram-positive and Gram-negative strains including Staphylococcus aureus (ATCC 6538), Bacillus subtilis (ATCC 6633), Bacillus licheniformis, Esherichia coli (ATCC 8739), Pseudomonas aeruginosa (ATCC 9027), Salmonella enterica (CIP 8039) and Salmonella typhimirium. The results of this antibacterial screening showed that the ethyl acetate (EtOAc) extracts had the best activity against the tested microorganisms. A bioassay-oriented fractionation approach for the more active extract (roots ethyl acetate extract) led to the obtaining five sub-fractions. Furthermore, these sub-fractions were also tested for antimicrobial activity and the best results were obtained for the roots EtOAc sub-fraction (C) with MICs values between 0.039 and 0.156 mg/mL. Reversed-phase high performance liquid chromatography (RP-HPLC) analysis indicated that the major phenolic components of active (EtOAc) extracts and sub-fraction (C) are fisetin hydrate (82.06%), trans cinnamic acid (63.66%), gallic acid (38.97%) and myricetin (20.92%). These results may help to improve these natural antibacterial substances that could serve as selective agents for bacterial diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

RG-I regions from elderflower pectins substituted on GalA are strong immunomodulators.

PubMed

Ho, Giang Thanh Thi; Zou, Yuan-Feng; Wangensteen, Helle; Barsett, Hilde

2016-11-01

Sambuci flos, also known as elderflower, has traditionally been used and is still in use for treatment of various types of illnesses related to the immune system such as cold, flu, fever and inflammation. Pectic polysaccharides from 50% EtOH, 50°C water and 100°C water extracts from elderflowers were treated with endo-α-d-(1-4)-polygalacturonase after previous de-esterification with the intention of isolating hairy regions and relate variation in structure to immunomodulating activity. High molecular weight sub-fractions (25-29kDa) and medium molecular weight sub-fractions (6-17kDa) were isolated after enzymatic treatment in addition to oligogalacturonides. Structural elucidation indicated that RG-I regions with AG-I and AG-II sidechains were the predominant structures in the high molecular weight sub-fractions, and two of three 1,4-linked GalA units in the rhamnogalacturonan backbone were branched in either position 2 or 3. The medium molecular weight sub-fractions had monomers and linkages typical for both RG-I and RG-II. The results showed that the high molecular RG-I containing polymers exhibit the highest dose-dependent complement fixing and macrophage stimulating activities. Copyright © 2016 Elsevier B.V. All rights reserved.

Heritage Language Development: Preserving a Mythic Past or Envisioning the Future of Canadian Identity?

ERIC Educational Resources Information Center

Guardado, Martin

2010-01-01

This article, part of a larger study, examines three middle-class, Hispanic Canadian families' conceptualizations of language, culture, and identity. Via an analysis of interview data, the findings indicate that the parents assigned diverse meanings to heritage language development (HLD) and held high expectations for their children's formation of…

High-level disinfection of gastrointestinal endoscope reprocessing

PubMed Central

Chiu, King-Wah; Lu, Lung-Sheng; Chiou, Shue-Shian

2015-01-01

High level disinfection (HLD) of the gastrointestinal (GI) endoscope is not simply a slogan, but rather is a form of experimental monitoring-based medicine. By definition, GI endoscopy is a semicritical medical device. Hence, such medical devices require major quality assurance for disinfection. And because many of these items are temperature sensitive, low-temperature chemical methods, such as liquid chemical germicide, must be used rather than steam sterilization. In summarizing guidelines for infection prevention and control for GI endoscopy, there are three important steps that must be highlighted: manual washing, HLD with automated endoscope reprocessor, and drying. Strict adherence to current guidelines is required because compared to any other medical device, the GI endoscope is associated with more outbreaks linked to inadequate cleaning or disinfecting during HLD. Both experimental evaluation on the surveillance bacterial cultures and in-use clinical results have shown that, the monitoring of the stringent processes to prevent and control infection is an essential component of the broader strategy to ensure the delivery of safe endoscopy services, because endoscope reprocessing is a multistep procedure involving numerous factors that can interfere with its efficacy. Based on our years of experience in the surveillance of culture monitoring of endoscopic reprocessing, we aim in this study to carefully describe what details require attention in the GI endoscopy disinfection and to share our experience so that patients can be provided with high quality and safe medical practices. Quality management encompasses all aspects of pre- and post-procedural care including the efficiency of the endoscopy unit and reprocessing area, as well as the endoscopic procedure itself. PMID:25699232

Effect of lateralized design on muscle and joint reaction forces for reverse shoulder arthroplasty.

PubMed

Liou, William; Yang, Yang; Petersen-Fitts, Graysen R; Lombardo, Daniel J; Stine, Sasha; Sabesan, Vani J

2017-04-01

Manufacturers of reverse shoulder arthroplasty (RSA) implants have recently designed innovative implants to optimize performance in rotator cuff-deficient shoulders. These advancements are not without tradeoffs and can have negative biomechanical effects. The objective of this study was to develop an integrated finite element analysis-kinematic model to compare the muscle forces and joint reaction forces (JRFs) of 3 different RSA designs. A kinematic model of a normal shoulder joint was adapted from the Delft model and integrated with the well-validated OpenSim shoulder model. Static optimizations then allowed for calculation of the individual muscle forces, moment arms, and JRFs relative to net joint moments. Three-dimensional computer models of 3 RSA designs-humeral lateralized design (HLD), glenoid lateralized design, and Grammont design-were integrated, and parametric studies were performed. Overall, there were decreases in deltoid and rotator cuff muscle forces for all 3 RSA designs. These decreases were greatest in the middle deltoid of the HLD model for abduction and flexion and in the rotator cuff muscles under both internal rotation and external rotation. The JRFs in abduction and flexion decreased similarly for all RSA designs compared with the normal shoulder model, with the greatest decrease seen in the HLD model. These findings demonstrate that the design characteristics implicit in these modified RSA prostheses result in mechanical differences most prominently seen in the deltoid muscle and overall JRFs. Further research using this novel integrated model can help guide continued optimization of RSA design and clinical outcomes. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

A Nascent Peptide Signal Responsive to Endogenous Levels of Polyamines Acts to Stimulate Regulatory Frameshifting on Antizyme mRNA.

PubMed

Yordanova, Martina M; Wu, Cheng; Andreev, Dmitry E; Sachs, Matthew S; Atkins, John F

2015-07-17

The protein antizyme is a negative regulator of cellular polyamine concentrations from yeast to mammals. Synthesis of functional antizyme requires programmed +1 ribosomal frameshifting at the 3' end of the first of two partially overlapping ORFs. The frameshift is the sensor and effector in an autoregulatory circuit. Except for Saccharomyces cerevisiae antizyme mRNA, the frameshift site alone only supports low levels of frameshifting. The high levels usually observed depend on the presence of cis-acting stimulatory elements located 5' and 3' of the frameshift site. Antizyme genes from different evolutionary branches have evolved different stimulatory elements. Prior and new multiple alignments of fungal antizyme mRNA sequences from the Agaricomycetes class of Basidiomycota show a distinct pattern of conservation 5' of the frameshift site consistent with a function at the amino acid level. As shown here when tested in Schizosaccharomyces pombe and mammalian HEK293T cells, the 5' part of this conserved sequence acts at the nascent peptide level to stimulate the frameshifting, without involving stalling detectable by toe-printing. However, the peptide is only part of the signal. The 3' part of the stimulator functions largely independently and acts at least mostly at the nucleotide level. When polyamine levels were varied, the stimulatory effect was seen to be especially responsive in the endogenous polyamine concentration range, and this effect may be more general. A conserved RNA secondary structure 3' of the frameshift site has weaker stimulatory and polyamine sensitizing effects on frameshifting. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Late Quaternary lake-level changes constrained by radiocarbon and stable isotope studies on sediment cores from Lake Titicaca, South America

NASA Astrophysics Data System (ADS)

Rowe, Harold D.; Guilderson, Thomas P.; Dunbar, Robert B.; Southon, John R.; Seltzer, Geoffrey O.; Mucciarone, David A.; Fritz, Sherilyn C.; Baker, Paul A.

2003-09-01

We present and compare AMS- 14C geochronologies for sediment cores recovered from Lake Titicaca, South America. Radiocarbon dates from three core sites constrain the timing of late Quaternary paleoenvironmental changes in the Central Andes and highlight the site-specific factors that limit the radiocarbon geochronometer. With the exception of mid-Holocene sediments, all cores are generally devoid of macrophyte fragments, thus bulk organic fractions are used to build core chronologies. Comparisons of radiocarbon results for chemically defined fractions (bulk decalcified, humate, humin) suggest that ages derived from all fractions are generally coherent in the post-13,500 yr BP time interval. In the pre-13,500 yr BP time interval, ages derived from humate extracts are significantly younger (300-7000 years) than ages from paired humin residues. Gross age incoherencies between paired humate and humin sub-fractions in pre-13,500 yr BP sediments from all core sites probably reflect the net downward migration of humates. Ages derived from bulk decalcified fractions at our shallow water (90 m) and deep water (230 m) core sites consistently fall between ages derived from humate and humin sub-fractions in the pre-13,500 yr BP interval, reflecting that the bulk decalcified fraction is predominantly a mixture of humate and humin sub-fractions. Bulk decalcified ages from the pre-13,500 yr BP interval at our intermediate depth core site (150 m) are consistently older than humate (youngest) and humin sub-fractions. This uniform, reproducible pattern can be explained by the mobilization of a relatively older organic sub-fraction during and after the re-acidification step following the alkaline treatment of the bulk sediment. The inferred existence of this 'alkali-mobile, acid-soluble' sub-fraction implies a different depositional/post-depositional history that is potentially associated with a difference in source material. While internally consistent geochronologies can be

Ribosomal vaccines. I. Immunogenicity of ribosomal fractions isolated from Salmonella typhimurium and Yersinia pestis.

PubMed

Johnson, W

1972-06-01

The immunogenicity of ribosomes and ribosomal subfractions isolated from Yersina pestis and Salmonella typhimurium has been studied. Ribosomes and ribosomal protein isolated from S. typhimurium protected mice against lethal challenge. Ribosomal ribonucleic acid isolated by phenol extraction failed to induce any significant level of protection in mice. None of the ribosomes or ribosomal subfractions isolated from Y. pestis were effective in inducing immunity to lethal challenge. These results suggest that the immunogen of the ribosomal vaccine is protein.

Anti-helminthic activity of Momordica charantia L. against Fasciola hepatica eggs after twelve days of incubation in vitro.

PubMed

Pereira, Cíntia A J; Oliveira, Laura L S; Coaglio, Aytube L; Santos, Fernanda S O; Cezar, Rodolfo S M; Mendes, Tiago; Oliveira, Fernando L P; Conzensa, Gustavo; Lima, Walter S

2016-09-15

Fasciolosis, a parasitic disease caused by the trematode Fasciola hepatica underreported is expanding both in human and animal population, throughout the world. The constant use of synthetic drugs to treat this condition has led to the natural selection of resistant strains of the parasite. Hence, there is a growing focus on the potential anti-helminthic properties of medicinal plants and phytopharmaceuticals. The current study assessed the potential anti-fasciolicide action of Momordica charantia leaf extracts and fractions on the eggs of F. hepatica parasites. The lyophilized crude extract (CE) of M. charantia leaves and its sub-fractions, obtained from liquid-liquid partitioning with organic solvents, were analysed by High Performance Liquid Chromatography (HPLC), suspended in 1% DMSO and used in in vitro tests. Quadruplicates of 50F. hepatica eggs were incubated at 23°C with M. charantia leaf CE in different concentrations. After 12days no larvae were formed in eggs incubated with CE concentrations above 12.5mg/mL. Eggs incubated with CE sub-fractions at concentrations of 1000, 100, 10, 1, 0.1, 0.01μg/mL affected embryonic development, with n-butanol presenting the strongest inhibition of miracidia formation. In contrast, on the 12th day, 90% of the miracidia hatched in the control experiments using 0.03% DMSO whereas embryogenesis was completely abolished with any concentration of albendazole sulphoxide ABZ(SO). Chemical analysis of the CE and sub-fractions revealed a prominent presence of flavonoids. HPLC-MS confirmed Quercetin to be one of the main flavonoids present in the CE and the n-butanol subfraction. This is the first study to analyse the potential anti-fasciolicide action of M. charantia leaf CE and subfractions. Copyright © 2016 Elsevier B.V. All rights reserved.

Fractionation of distillers dried grains with solubles (DDGS) by sieving and winnowing.

PubMed

Liu, KeShun

2009-12-01

Four commercial samples of distillers dried grains with solubles (DDGS) were sieved. All sieved fractions except for the pan fraction, constituting about 90% of original mass, were then winnowed with an air blast seed cleaner. Sieving was effective in producing fractions with varying composition. As the particle size decreased, protein and ash contents increased, and total carbohydrate (CHO) decreased. Winnowing sieved fractions was also effective in shifting composition, particularly for larger particle classes. Heavy sub-fractions were enriched in protein, oil and ash, while light sub-fractions were enriched for CHO. For protein, the combination of the two procedures resulted in a maximum 56.4% reduction in a fraction and maximum 60.2% increase in another fraction. As airflow velocity increased, light sub-fraction mass increased, while the compositional difference between the heavy and light sub-fractions decreased. Winnowing three times at a lower velocity was as effective as winnowing one time at a medium velocity. Winnowing the whole DDGS was much less effective than winnowing sieved fractions in changing composition, but sieving winnowed fractions was more effective than sieving whole DDGS. The two combination sequences gave comparable overall effects but sieving followed by winnowing is recommended because it requires less time. Regardless of combinational sequence, the second procedure was more effective in shifting composition than the first procedure.

The FAK-Arp2/3 interaction promotes leading edge advance and haptosensing by coupling nascent adhesions to lamellipodia actin.

PubMed

Swaminathan, Vinay; Fischer, R S; Waterman, Clare M

2016-04-01

Cell migration is initiated in response to biochemical or physical cues in the environment that promote actin-mediated lamellipodial protrusion followed by the formation of nascent integrin adhesions (NAs) within the protrusion to drive leading edge advance. Although FAK is known to be required for cell migration through effects on focal adhesions, its role in NA formation and lamellipodial dynamics is unclear. Live-cell microscopy of FAK(-/-)cells with expression of phosphorylation deficient or a FERM-domain mutant deficient in Arp2/3 binding revealed a requirement for FAK in promoting the dense formation, transient stabilization, and timely turnover of NA within lamellipodia to couple actin-driven protrusion to adhesion and advance of the leading edge. Phosphorylation on Y397 of FAK promotes dense NA formation but is dispensable for transient NA stabilization and leading edge advance. In contrast, transient NA stabilization and advance of the cell edge requires FAK-Arp2/3 interaction, which promotes Arp2/3 localization to NA and reduces FAK activity. Haptosensing of extracellular matrix (ECM) concentration during migration requires the interaction between FAK and Arp2/3, whereas FAK phosphorylation modulates mechanosensing of ECM stiffness during spreading. Taken together, our results show that mechanistically separable functions of FAK in NA are required for cells to distinguish distinct properties of their environment during migration. © 2016 Swaminathan et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Ribosomal Vaccines I. Immunogenicity of Ribosomal Fractions Isolated from Salmonella typhimurium and Yersinia pestis

PubMed Central

Johnson, William

1972-01-01

The immunogenicity of ribosomes and ribosomal subfractions isolated from Yersina pestis and Salmonella typhimurium has been studied. Ribosomes and ribosomal protein isolated from S. typhimurium protected mice against lethal challenge. Ribosomal ribonucleic acid isolated by phenol extraction failed to induce any significant level of protection in mice. None of the ribosomes or ribosomal subfractions isolated from Y. pestis were effective in inducing immunity to lethal challenge. These results suggest that the immunogen of the ribosomal vaccine is protein. Images PMID:4564407

Surveillance cultures of samples obtained from biopsy channels and automated endoscope reprocessors after high-level disinfection of gastrointestinal endoscopes.

PubMed

Chiu, King-Wah; Tsai, Ming-Chao; Wu, Keng-Liang; Chiu, Yi-Chun; Lin, Ming-Tzung; Hu, Tsung-Hui

2012-09-03

The instrument channels of gastrointestinal (GI) endoscopes may be heavily contaminated with bacteria even after high-level disinfection (HLD). The British Society of Gastroenterology guidelines emphasize the benefits of manually brushing endoscope channels and using automated endoscope reprocessors (AERs) for disinfecting endoscopes. In this study, we aimed to assess the effectiveness of decontamination using reprocessors after HLD by comparing the cultured samples obtained from biopsy channels (BCs) of GI endoscopes and the internal surfaces of AERs. We conducted a 5-year prospective study. Every month random consecutive sampling was carried out after a complete reprocessing cycle; 420 rinse and swabs samples were collected from BCs and internal surface of AERs, respectively. Of the 420 rinse samples collected from the BC of the GI endoscopes, 300 were obtained from the BCs of gastroscopes and 120 from BCs of colonoscopes. Samples were collected by flushing the BCs with sterile distilled water, and swabbing the residual water from the AERs after reprocessing. These samples were cultured to detect the presence of aerobic and anaerobic bacteria and mycobacteria. The number of culture-positive samples obtained from BCs (13.6%, 57/420) was significantly higher than that obtained from AERs (1.7%, 7/420). In addition, the number of culture-positive samples obtained from the BCs of gastroscopes (10.7%, 32/300) and colonoscopes (20.8%, 25/120) were significantly higher than that obtained from AER reprocess to gastroscopes (2.0%, 6/300) and AER reprocess to colonoscopes (0.8%, 1/120). Culturing rinse samples obtained from BCs provides a better indication of the effectiveness of the decontamination of GI endoscopes after HLD than culturing the swab samples obtained from the inner surfaces of AERs as the swab samples only indicate whether the AERs are free from microbial contamination or not.

Surveillance cultures of samples obtained from biopsy channels and automated endoscope reprocessors after high-level disinfection of gastrointestinal endoscopes

PubMed Central

2012-01-01

Background The instrument channels of gastrointestinal (GI) endoscopes may be heavily contaminated with bacteria even after high-level disinfection (HLD). The British Society of Gastroenterology guidelines emphasize the benefits of manually brushing endoscope channels and using automated endoscope reprocessors (AERs) for disinfecting endoscopes. In this study, we aimed to assess the effectiveness of decontamination using reprocessors after HLD by comparing the cultured samples obtained from biopsy channels (BCs) of GI endoscopes and the internal surfaces of AERs. Methods We conducted a 5-year prospective study. Every month random consecutive sampling was carried out after a complete reprocessing cycle; 420 rinse and swabs samples were collected from BCs and internal surface of AERs, respectively. Of the 420 rinse samples collected from the BC of the GI endoscopes, 300 were obtained from the BCs of gastroscopes and 120 from BCs of colonoscopes. Samples were collected by flushing the BCs with sterile distilled water, and swabbing the residual water from the AERs after reprocessing. These samples were cultured to detect the presence of aerobic and anaerobic bacteria and mycobacteria. Results The number of culture-positive samples obtained from BCs (13.6%, 57/420) was significantly higher than that obtained from AERs (1.7%, 7/420). In addition, the number of culture-positive samples obtained from the BCs of gastroscopes (10.7%, 32/300) and colonoscopes (20.8%, 25/120) were significantly higher than that obtained from AER reprocess to gastroscopes (2.0%, 6/300) and AER reprocess to colonoscopes (0.8%, 1/120). Conclusions Culturing rinse samples obtained from BCs provides a better indication of the effectiveness of the decontamination of GI endoscopes after HLD than culturing the swab samples obtained from the inner surfaces of AERs as the swab samples only indicate whether the AERs are free from microbial contamination or not. PMID:22943739

Floral aroma improvement of Muscat spirits by packed column distillation with variable internal reflux.

PubMed

Matias-Guiu, Pau; Rodríguez-Bencomo, Juan José; Orriols, Ignacio; Pérez-Correa, José Ricardo; López, Francisco

2016-12-15

The organoleptic quality of wine distillates depends on raw materials and the distillation process. Previous work has shown that rectification columns in batch distillation with fixed reflux rate are useful to obtain distillates or distillate fractions with enhanced organoleptic characteristics. This study explores variable reflux rate operating strategies to increase the levels of terpenic compounds in specific distillate fractions to emphasize its floral aroma. Based on chemical and sensory analyses, two distillate heart sub-fractions obtained with the best operating strategy found, were compared with a distillate obtained in a traditional alembic. Results have shown that a drastic reduction of the reflux rate at an early stage of the heart cut produced a distillate heart sub-fraction with a higher concentration of terpenic compounds and lower levels of negative aroma compounds. Therefore, this sub-fraction presented a much more noticeable floral aroma than the distillate obtained with a traditional alembic. Copyright © 2016 Elsevier Ltd. All rights reserved.

Population and forensic data for three sets of forensic genetic markers in four ethnic groups from Iran: Persians, Lurs, Kurds and Azeris.

PubMed

Poulsen, L; Farzad, M Sharafi; Børsting, C; Tomas, C; Pereira, V; Morling, N

2015-07-01

A total of 255 individuals (Persians, Lurs, Kurds and Azeris) from Iran were typed for three sets of forensic genetic markers with the NGM SElect™, DIPplex(®) and Argus X-12 kits. Statistically significant deviations (P≤0.002) from Hardy-Weinberg expectations were observed for the insertion-deletion markers HLD97 and HLD93 after Holm-Šidák correction. Statistically significant (P<0.05) levels of linkage disequilibrium were observed between markers within two of the four studied X-chromosomal linkage groups. AMOVA analyses of the three sets of markers did not show population structure when the individuals were grouped according to their ethnic group. The Iranian population grouped closely to populations living geographically near to Iran based on pairwise FST distances. The matching probabilities ranged from 1 in 3.2×10(7) males by using haplotype frequencies of four X-chromosomal haplogroups to 1 in 3.4×10(21) individuals for the 16 autosomal STRs. Copyright © 2015. Published by Elsevier Ireland Ltd.

Distinguishing black carbon from biogenic humic substances in soil clay fractions

USGS Publications Warehouse

Laird, D.A.; Chappell, M.A.; Martens, D.A.; Wershaw, R. L.; Thompson, M.

2008-01-01

Most models of soil humic substances include a substantial component of aromatic C either as the backbone of humic heteropolymers or as a significant component of supramolecular aggregates of degraded biopolymers. We physically separated coarse (0.2-2.0????m e.s.d.), medium (0.02-0.2????m e.s.d.), and fine (> 0.02????m e.s.d.) clay subfractions from three Midwestern soils and characterized the organic material associated with these subfractions using 13C-CPMAS-NMR, DTG, SEM-EDX, incubations, and radiocarbon age. Most of the C in the coarse clay subfraction was present as discrete particles (0.2-5????m as seen in SEM images) of black carbon (BC) and consisted of approximately 60% aromatic C, with the remainder being a mixture of aliphatic, anomeric and carboxylic C. We hypothesize that BC particles were originally charcoal formed during prairie fires. As the BC particles aged in soil their surfaces were oxidized to form carboxylic groups and anomeric and aliphatic C accumulated in the BC particles either by adsorption of dissolved biogenic compounds from the soil solution or by direct deposition of biogenic materials from microbes living within the BC particles. The biogenic soil organic matter was physically separated with the medium and fine clay subfractions and was dominated by aliphatic, anomeric, and carboxylic C. The results indicate that the biogenic humic materials in our soils have little aromatic C, which is inconsistent with the traditional heteropolymer model of humic substances.

Chemical analysis and biological testing of a polar fraction of ambient air, diesel engine, and gasoline engine particulate extracts.

PubMed Central

Strandell, M; Zakrisson, S; Alsberg, T; Westerholm, R; Winquist, L; Rannug, U

1994-01-01

Extracts of gasoline and diesel vehicle exhaust and ambient air particles were fractionated into five fractions according to polarity on a silica gel column. Two medium polar fractions showing high genotoxic activity in the Ames test were further subfractionated, using normal-phase high-performance liquid chromatography. Chemical analyses were performed by means of gas chromatography combined with mass spectrometry and flame ionization and detection. The crude extracts, fractions, and subfractions were assayed with the Ames test, with and without S9, and the most abundant compounds in the subfractions are reported. PMID:7529708

In vitro antibacterial, antifungal, and antioxidant activities of the essential oil and methanol extracts of herbal parts and callus cultures of Satureja hortensis L.

PubMed

Güllüce, M; Sökmen, M; Daferera, D; Ağar, G; Ozkan, H; Kartal, N; Polissiou, M; Sökmen, A; Sahin, F

2003-07-02

The present study was designated to evaluate the antimicrobial and antioxidant activities of the essential oil, obtained by using a Clevenger distillation apparatus, water soluble (polar) and water insoluble (nonpolar) subfractions of the methanol extracts from aerial parts of Satureja hortensis L. plants, and methanol extract from calli established from the seeds using Gamborg's B5 basal media supplemented with indole-3-butyric acid (1.0 ppm), 6-benzylaminopurine (N(6)-benzyladenine) (1.0 ppm), and sucrose (2.5%). The antimicrobial test results showed that the essential oil of S. hortensis had great potential antimicrobial activities against all 23 bacteria and 15 fungi and yeast species tested. In contrast, the methanol extract from callus cultures and water soluble subfraction of the methanol extract did not show antimicrobial activities, but the nonpolar subfraction had antibacterial activity against only five out of 23 bacterial species, which were Bacillus subtilis, Enterococcus fecalis, Pseudomonas aeruginosa, Salmonella enteritidis, and Streptococcus pyogenes. Antioxidant studies suggested that the polar subfractions of the methanol extract of intact plant and methanol extract of callus cultures were able to reduce the stable free radical 2,2-diphenyl-1-picrylhydrazyl to the yellow-colored diphenylpicrylhydrazine. In this assay, the strongest effect was observed for the tissue culture extract, with an IC(50) value of 23.76 +/- 0.80 microgram/mL, which could be compared with the synthetic antioxidant agent butylated hydroxytoluene. On the other hand, linoleic acid oxidation was 95% inhibited in the presence of the essential oil while the inhibition was 90% with the chloroform subfraction of the intact plant. The chemical composition of a hydrodistilled essential oil of S. hortensis was analyzed by gas chromatography (GC)/flame ionization detection (FID) and a GC-mass spectrometry system. A total 22 constituents representing 99.9% of the essential oil were

Nascent Leadership Behaviors

ERIC Educational Resources Information Center

Payette, Dennis L.; Libertella, Anthony F.

2011-01-01

This paper is a compendium of leadership behaviors that emerging or aspirant leaders could choose to enhance their management and leadership skills. These behaviors were drawn directly from the experience of the authors, both of whom have held senior leadership and management positions in business, law, and higher education. This paper is an…

Mechanistic studies of high-density lipoproteins.

PubMed

Kashyap, M L

1998-12-17

There is increasing evidence that high-density lipoprotein (HDL) and its subfractions are protective against atherosclerotic cardiovascular disease. Physical exercise, weight reduction, smoking cessation, diabetes mellitus control, and specific drugs, including niacin, fibrates, and estrogens, are effective methods to increase HDL levels. Niacin is the oldest and most powerful clinical agent for raising HDL levels. Niaspan, an extended-release niacin formulation, is as potent as immediate-release niacin in increasing levels of HDL cholesterol; subfractions HDL2 and HDL3; apolipoprotein A-I, the major protein of HDL, and its cardioprotective subfraction lipoprotein A-I. Recent research from our laboratory suggests a novel mechanism by which niacin inhibits hepatic removal of HDL-apoprotein A-I without interfering with the removal of cholesterol carried by HDL, thus augmenting reverse cholesterol transport. Other mechanistic studies indicate that fibrates and estrogens stimulate the synthesis and production of HDL-apoprotein A-I. Because niacin decreases HDL-apoprotein A-I removal, and fibrates and estrogens increase HDL-apoprotein A-I production, combinations of niacin with these agents may raise HDL levels more than fibrates or estrogens alone.

Proteomic Analysis of the Neurotrophic Effect of Gelidium amansii in Primary Cultured Neurons.

PubMed

Hannan, Md Abdul; Mohibbullah, Md; Hong, Yong-Ki; Moon, Il Soo

2017-03-01

Gelidium amansii is an edible and economically important red alga consumed in South Eastern Asia. In previous studies, we reported that the ethanol extracts of G. amansii (GAE) has promising modulatory activity with respect to the morphological and functional maturation of hippocampal neurons in culture. In this study, we show that the chloroform (CHCl 3 ) subfraction of GAE and the ethyl acetate (EtOAc) fraction dose-dependently promoted neurite outgrowth, and their effects were comparable with that of GAE. We further assessed in cultured cortical neurons, proteins differentially expressed in the presence/absence of the GAE, CHCl 3 subfraction, and the EtOAc fraction by 2D-PAGE and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Proteomic data revealed that a number of proteins responsible for multiple cellular and biochemical functions vital for neuronal development and maturation were significantly upregulated in neurons treated with the GAE, CHCl 3 subfraction, and the EtOAc fraction. Of the identified proteins, profilin 2a, septin 7, cdc42, protein phosphatase 2A, DA11, eukaryotic translation initiation factor 5A-1, and γ-enolase are known to play important roles in neuritogenesis and dendritic arborization. Immunofluorescence data demonstrate that GAE-treated hippocampal neurons showed greater intensity ratios in the expressions of the septin 7 and cdc42 compared to vehicle control, validating their proteomic profiles. Together these results suggest that the GAE/CHCl 3 subfraction and EtOAc fraction promote neurite development by up or downregulating several key proteins.

Phytochemical Characterization of Terminalia catappa Linn. Extracts and Their antifungal Activities against Candida spp.

PubMed

Terças, Analucia G; Monteiro, Andrea de Souza; Moffa, Eduardo B; Dos Santos, Julliana R A; de Sousa, Eduardo M; Pinto, Anna R B; Costa, Paola C da Silva; Borges, Antonio C R; Torres, Luce M B; Barros Filho, Allan K D; Fernandes, Elizabeth S; Monteiro, Cristina de Andrade

2017-01-01

Terminalia catappa Linn bark is used to treat dysentery by various populations in Southeast Asian countries, and its leaves have also been used in traditional medicine to treat hepatitis in India and the Philippines. Here, the antifungal actions of crude hydro-alcoholic extract (TcHE) and fractions from T. catappa leaves were assessed via the agar diffusion and microdilution tests on Candida reference strains and clinical isolates from patients with acquired immunodeficiency syndrome (AIDS). Additionally, the potential cytotoxic effects of TcHE were assessed on cultured human peripheral blood mononuclear cells (PBMC). T. catappa fractions and sub-fractions were analyzed by gas chromatography coupled to mass spectrometry with electron impact (GC/MS/EI), high-performance liquid chromatography coupled to mass spectrometry "electrospray" ionization in positive mode (HPLC/MS/MS/ESI + ) and hydrogen nuclear magnetic resonance ( 1 HNMR). TcHE and its fractions were able to inhibit the growth of all tested Candida strains with the n -butanol (FBuOH) fraction presenting the best antifungal activity. Testing of different FBuOH sub-fractions (SF) showed that SF10 was the most active against Candida spp. Fractioning of SF10 demonstrated that 5 out of its 15 sub-fractions were active against Candida spp., with SF10.5 presenting the highest activity. Chemical analysis of SF10 detected hydrolysable tannins (punicalin, punicalagin), gallic acid and flavonoid C-glycosides. Overall, the results showed that T. catappa L. leaf extract, fractions and sub-fractions were antifungal against Candida spp. and may be useful to treat diseases caused by this fungus.

Phytochemical Characterization of Terminalia catappa Linn. Extracts and Their antifungal Activities against Candida spp.

PubMed Central

Terças, Analucia G.; Monteiro, Andrea de Souza; Moffa, Eduardo B.; dos Santos, Julliana R. A.; de Sousa, Eduardo M.; Pinto, Anna R. B.; Costa, Paola C. da Silva; Borges, Antonio C. R.; Torres, Luce M. B.; Barros Filho, Allan K. D.; Fernandes, Elizabeth S.; Monteiro, Cristina de Andrade

2017-01-01

Terminalia catappa Linn bark is used to treat dysentery by various populations in Southeast Asian countries, and its leaves have also been used in traditional medicine to treat hepatitis in India and the Philippines. Here, the antifungal actions of crude hydro-alcoholic extract (TcHE) and fractions from T. catappa leaves were assessed via the agar diffusion and microdilution tests on Candida reference strains and clinical isolates from patients with acquired immunodeficiency syndrome (AIDS). Additionally, the potential cytotoxic effects of TcHE were assessed on cultured human peripheral blood mononuclear cells (PBMC). T. catappa fractions and sub-fractions were analyzed by gas chromatography coupled to mass spectrometry with electron impact (GC/MS/EI), high-performance liquid chromatography coupled to mass spectrometry “electrospray” ionization in positive mode (HPLC/MS/MS/ESI+) and hydrogen nuclear magnetic resonance (1HNMR). TcHE and its fractions were able to inhibit the growth of all tested Candida strains with the n-butanol (FBuOH) fraction presenting the best antifungal activity. Testing of different FBuOH sub-fractions (SF) showed that SF10 was the most active against Candida spp. Fractioning of SF10 demonstrated that 5 out of its 15 sub-fractions were active against Candida spp., with SF10.5 presenting the highest activity. Chemical analysis of SF10 detected hydrolysable tannins (punicalin, punicalagin), gallic acid and flavonoid C-glycosides. Overall, the results showed that T. catappa L. leaf extract, fractions and sub-fractions were antifungal against Candida spp. and may be useful to treat diseases caused by this fungus. PMID:28443078

Antimicrobial and antioxidant activity of the essential oil and methanol extracts of Thymus pectinatus Fisch. et Mey. Var. pectinatus (Lamiaceae).

PubMed

Vardar-Unlü, Gülhan; Candan, Ferda; Sökmen, Atalay; Daferera, Dimitra; Polissiou, Moschos; Sökmen, Münevver; Dönmez, Erol; Tepe, Bektaş

2003-01-01

The essential oil, obtained by using a Clevenger distillation apparatus, and water-soluble (polar) and water-insoluble (nonpolar) subfractions of the methanol extract of Thymus pectinatus Fisch. et Mey. var. pectinatus were assayed for their antimicrobial and antioxidant properties. No (or slight) antimicrobial activity was observed when the subfractions were tested, whereas the essential oil showed strong antimicrobial activity against all microorganisms tested. Antioxidant activities of the polar subfraction and the essential oil were evaluated using 2,2-diphenyl-1-picrylhydrazyl, hydroxyl radical, superoxide radical scavenging, and lipid peroxidation assays. The essential oil, in particular, and the polar subfraction of the methanol extract showed antioxidant activity. The essential oil was analyzed by GC/MS, and 24 compounds, representing 99.6% of the essential oil, were identified: thymol, gamma-terpinene, p-cymene, carvacrol, and borneol were the main components. An antimicrobial activity test carried out with fractions of the essential oil showed that the activity was mainly observed in those fractions containing thymol, in particular, and carvacrol. The activity was, therefore, attributed to the presence of these compounds. Other constituents of the essential oil, such as borneol, gamma-terpinene, and p-cymene, could be also taken into account for their possible synergistic or antagonistic effects. On the other hand, thymol and carvacrol were individually found to possess weaker antioxidant activity than the crude oil itself, indicating that other constituents of the essential oil may contribute to the antioxidant activity observed. In conclusion, the results presented here show that T. pectinatus essential oil could be considered as a natural antimicrobial and antioxidant source.

Identification and evaluation of vaccine candidate antigens from the poultry red mite (Dermanyssus gallinae)

PubMed Central

Bartley, Kathryn; Wright, Harry W.; Huntley, John F.; Manson, Erin D.T.; Inglis, Neil F.; McLean, Kevin; Nath, Mintu; Bartley, Yvonne; Nisbet, Alasdair J.

2015-01-01

An aqueous extract of the haematophagous poultry ectoparasite, Dermanyssus gallinae, was subfractionated using anion exchange chromatography. Six of these subfractions were used to immunise hens and the blood from these hens was fed, in vitro, to poultry red mites. Mite mortality following these feeds was indicative of protective antigens in two of the subfractions, with the risks of mites dying being 3.1 and 3.7 times higher than in the control group (P < 0.001). A combination of two-dimensional immunoblotting and immunoaffinity chromatography, using IgY from hens immunised with these subfractions, was used in concert with proteomic analyses to identify the strongest immunogenic proteins in each of these subfractions. Ten of the immunoreactive proteins were selected for assessment as vaccine candidates using the following criteria: intensity of immune recognition; likelihood of exposure of the antigen to the antibodies in a blood meal; proposed function and known vaccine potential of orthologous molecules. Recombinant versions of each of these 10 proteins were produced in Escherichia coli and were used to immunise hens. Subsequent in vitro feeding of mites on blood from these birds indicated that immunisation with Deg-SRP-1 (serpin), Deg-VIT-1 (vitellogenin), Deg-HGP-1 (hemelipoglycoprotein) or Deg-PUF-1 (a protein of unknown function) resulted in significantly increased risk of mite death (1.7–2.8 times higher than in mites fed blood from control hens immunised with adjuvant only, P < 0.001). The potential for using these antigens in a recombinant vaccine is discussed. PMID:26296690

Identification and evaluation of vaccine candidate antigens from the poultry red mite (Dermanyssus gallinae).

PubMed

Bartley, Kathryn; Wright, Harry W; Huntley, John F; Manson, Erin D T; Inglis, Neil F; McLean, Kevin; Nath, Mintu; Bartley, Yvonne; Nisbet, Alasdair J

2015-11-01

An aqueous extract of the haematophagous poultry ectoparasite, Dermanyssus gallinae, was subfractionated using anion exchange chromatography. Six of these subfractions were used to immunise hens and the blood from these hens was fed, in vitro, to poultry red mites. Mite mortality following these feeds was indicative of protective antigens in two of the subfractions, with the risks of mites dying being 3.1 and 3.7 times higher than in the control group (P<0.001). A combination of two-dimensional immunoblotting and immunoaffinity chromatography, using IgY from hens immunised with these subfractions, was used in concert with proteomic analyses to identify the strongest immunogenic proteins in each of these subfractions. Ten of the immunoreactive proteins were selected for assessment as vaccine candidates using the following criteria: intensity of immune recognition; likelihood of exposure of the antigen to the antibodies in a blood meal; proposed function and known vaccine potential of orthologous molecules. Recombinant versions of each of these 10 proteins were produced in Escherichia coli and were used to immunise hens. Subsequent in vitro feeding of mites on blood from these birds indicated that immunisation with Deg-SRP-1 (serpin), Deg-VIT-1 (vitellogenin), Deg-HGP-1 (hemelipoglycoprotein) or Deg-PUF-1 (a protein of unknown function) resulted in significantly increased risk of mite death (1.7-2.8times higher than in mites fed blood from control hens immunised with adjuvant only, P<0.001). The potential for using these antigens in a recombinant vaccine is discussed. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Ab initio prediction of fast non-equilibrium transport of nascent polarons in SrI2: a key to high-performance scintillation

NASA Astrophysics Data System (ADS)

Zhou, Fei; Sadigh, Babak; Erhart, Paul; Åberg, Daniel

2016-08-01

The excellent light yield proportionality of europium-doped strontium iodide (SrI2:Eu) has resulted in state-of-the-art γ-ray detectors with remarkably high-energy resolution, far exceeding that of most halide compounds. In this class of materials, the formation of self-trapped hole polarons is very common. However, polaron formation is usually expected to limit carrier mobilities and has been associated with poor scintillator light-yield proportionality and resolution. Here using a recently developed first-principles method, we perform an unprecedented study of polaron transport in SrI2, both for equilibrium polarons, as well as nascent polarons immediately following a self-trapping event. We propose a rationale for the unexpected high-energy resolution of SrI2. We identify nine stable hole polaron configurations, which consist of dimerised iodine pairs with polaron-binding energies of up to 0.5 eV. They are connected by a complex potential energy landscape that comprises 66 unique nearest-neighbour migration paths. Ab initio molecular dynamics simulations reveal that a large fraction of polarons is born into configurations that migrate practically barrier free at room temperature. Consequently, carriers created during γ-irradiation can quickly diffuse away reducing the chance for non-linear recombination, the primary culprit for non-proportionality and resolution reduction. We conclude that the flat, albeit complex, landscape for polaron migration in SrI2 is a key for understanding its outstanding performance. This insight provides important guidance not only for the future development of high-performance scintillators but also of other materials, for which large polaron mobilities are crucial such as batteries and solid-state ionic conductors.

Treatment outcomes in 3 modes of orthodontic practice.

PubMed

Poulton, Donald R; Baumrind, Sheldon; Vlaskalic, Vicki

2002-02-01

This study examined differences in pretreatment severity and treatment outcome among orthodontic patients treated in 3 different practice-management modes. Samples of pretreatment (T1) and end of treatment (T2) study casts were selected from traditional private practices (TPP, 3 offices, 81 cases), a dental corporation (COMP, 2 offices, 53 cases), and a dental management service organization (DMSO, 1 office, 36 cases). Orthodontic specialists had treated all patients. Cases were initially selected on a consecutive start basis. From each practice, the first 30 cases satisfying the study criteria were included in the sample. The T1 and T2 study casts were evaluated with the PAR and HLD indexes. The PAR and HLD indexes showed a high level of agreement on T1 cast scores but not on the T2 casts. Mean T1 scores were highest in the COMP cases, followed by the DMSO and the TPP cases. T2 scores were lowest in the TPP cases, followed by the DMSO and the COMP cases. The percentage of PAR score reduction showed that, in all 3 modes, patients were treated to a high standard.

Response of AM fungi spore population to elevated temperature and nitrogen addition and their influence on the plant community composition and productivity

NASA Astrophysics Data System (ADS)

Zhang, Tao; Yang, Xue; Guo, Rui; Guo, Jixun

2016-04-01

To examine the influence of elevated temperature and nitrogen (N) addition on species composition and development of arbuscular mycorrhizal fungi (AMF) and the effect of AMF on plant community structure and aboveground productivity, we conducted a 5-year field experiment in a temperate meadow in northeast China and a subsequent greenhouse experiment. In the field experiment, N addition reduced spore population diversity and richness of AMF and suppressed the spore density and the hyphal length density (HLD). Elevated temperature decreased spore density and diameter and increased the HLD, but did not affect AMF spore population composition. In the greenhouse experiment, AMF altered plant community composition and increased total aboveground biomass in both elevated temperature and N addition treatments; additionally, AMF also increased the relative abundance and aboveground biomass of the grasses Leymus chinensis (Poaceae) and Setaria viridis (Gramineae) and significantly reduced the relative abundance and aboveground biomass of the Suaeda corniculata (Chenopodiaceae). Although elevated temperature and N addition can affect species composition or suppress the development of AMF, AMF are likely to play a vital role in increasing plant diversity and productivity. Notably, AMF might reduce the threat of climate change induced degradation of temperate meadow ecosystems.

Computing Rydberg Electron Transport Rates Using Periodic Orbits

NASA Astrophysics Data System (ADS)

Sattari, Sulimon; Mitchel, Kevin

2017-04-01

Electron transport rates in chaotic atomic systems are computable from classical periodic orbits. This technique allows for replacing a Monte Carlo simulation launching millions of orbits with a sum over tens or hundreds of properly chosen periodic orbits using a formula called the spectral determiant. A firm grasp of the structure of the periodic orbits is required to obtain accurate transport rates. We apply a technique called homotopic lobe dynamics (HLD) to understand the structure of periodic orbits to compute the ionization rate in a classically chaotic atomic system, namely the hydrogen atom in strong parallel electric and magnetic fields. HLD uses information encoded in the intersections of stable and unstable manifolds of a few orbits to compute relevant periodic orbits in the system. All unstable periodic orbits are computed up to a given period, and the ionization rate computed from periodic orbits converges exponentially to the true value as a function of the period used. Using periodic orbit continuation, the ionization rate is computed over a range of electron energy and magnetic field values. The future goal of this work is to semiclassically compute quantum resonances using periodic orbits.

Response of AM fungi spore population to elevated temperature and nitrogen addition and their influence on the plant community composition and productivity

PubMed Central

Zhang, Tao; Yang, Xue; Guo, Rui; Guo, Jixun

2016-01-01

To examine the influence of elevated temperature and nitrogen (N) addition on species composition and development of arbuscular mycorrhizal fungi (AMF) and the effect of AMF on plant community structure and aboveground productivity, we conducted a 5-year field experiment in a temperate meadow in northeast China and a subsequent greenhouse experiment. In the field experiment, N addition reduced spore population diversity and richness of AMF and suppressed the spore density and the hyphal length density (HLD). Elevated temperature decreased spore density and diameter and increased the HLD, but did not affect AMF spore population composition. In the greenhouse experiment, AMF altered plant community composition and increased total aboveground biomass in both elevated temperature and N addition treatments; additionally, AMF also increased the relative abundance and aboveground biomass of the grasses Leymus chinensis (Poaceae) and Setaria viridis (Gramineae) and significantly reduced the relative abundance and aboveground biomass of the Suaeda corniculata (Chenopodiaceae). Although elevated temperature and N addition can affect species composition or suppress the development of AMF, AMF are likely to play a vital role in increasing plant diversity and productivity. Notably, AMF might reduce the threat of climate change induced degradation of temperate meadow ecosystems. PMID:27098761

Expanding the clinical and genetic spectra of NKX6-2-related disorder.

PubMed

Baldi, C; Bertoli-Avella, A M; Al-Sannaa, N; Alfadhel, M; Al-Thihli, K; Alameer, S; Elmonairy, A A; Al Shamsi, A M; Abdelrahman, H A; Al-Gazali, L; Shawli, A; Al-Hakami, F; Yavuz, H; Kandaswamy, K K; Rolfs, A; Brandau, O; Bauer, P

2018-05-01

Hypomyelinating leukodystrophies (HLDs) affect the white matter of the central nervous system and manifest as neurological disorders. They are genetically heterogeneous. Very recently, biallelic variants in NKX6-2 have been suggested to cause a novel form of autosomal recessive HLD. Using whole-exome or whole-genome sequencing, we identified the previously reported c.196delC and c.487C>G variants in NKX6-2 in 3 and 2 unrelated index cases, respectively; the novel c.608G>A variant was identified in a sixth patient. All variants were homozygous in affected family members only. Our patients share a primary diagnosis of psychomotor delay, and they show spastic quadriparesis, nystagmus and hypotonia. Seizures and dysmorphic features (observed in 2 families each) represent an addition to the phenotype, while developmental regression (observed in 3 families) appears to be a notable and previously underestimated clinical feature. Our findings extend the clinical and mutational spectra associated with this novel form of HLD. Comparative analysis of our 10 patients and the 15 reported previously did, however, not reveal clear evidence for a genotype-phenotype correlation. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Genetic polymorphism and forensic application of 30 InDel loci of Han population in Beijing].

PubMed

Bai, Ru-Feng; Jiang, Li-Zhe; Zhang, Zhong; Shi, Mei-Sen

2013-12-01

To study the genetic diversities of 30 insertion-deletion (InDel) polymorphisms loci of Han population in Beijing, and to evaluate their forensic application, 210 unrelated healthy individuals of Han population in Beijing were investigated to determine the distributions of allele frequencies by using Investigator DIP system. The PCR products were detected with ABI 3130 XL Genetic Analyzer. Forensic parameters were calculated with relevant statistical analysis software. As a result, after the Bonferroni correction at a 95% significance level, there were no significant departures from Hardy-Weinberg equilibrium or significant linkage disequilibrium between the loci. The power of discrimination (DP) varies between 0.2690 (HLD118) and 0.6330 (HLD45), and the combined discrimination power (TDP) for the 30 InDel loci is 0.999999999985. The combined power of exclusion was 0.98771049 in trio cases (CPE(trio)) and 0.94579456 in duo cases (CPE(duo)). The parentage testing of 32 cases revealed no mutations happened to 30 InDel loci. Multiplex detection of the 30 InDel loci revealed a highly polymorphic genetic distribution in Beijing Han population, which represents a complementary tool in human identification studies, especially in challenging DNA cases.

Swab culture monitoring of automated endoscope reprocessors after high-level disinfection

PubMed Central

Lu, Lung-Sheng; Wu, Keng-Liang; Chiu, Yi-Chun; Lin, Ming-Tzung; Hu, Tsung-Hui; Chiu, King-Wah

2012-01-01

AIM: To conduct a bacterial culture study for monitoring decontamination of automated endoscope reprocessors (AERs) after high-level disinfection (HLD). METHODS: From February 2006 to January 2011, authors conducted randomized consecutive sampling each month for 7 AERs. Authors collected a total of 420 swab cultures, including 300 cultures from 5 gastroscope AERs, and 120 cultures from 2 colonoscope AERs. Swab cultures were obtained from the residual water from the AERs after a full reprocessing cycle. Samples were cultured to test for aerobic bacteria, anaerobic bacteria, and mycobacterium tuberculosis. RESULTS: The positive culture rate of the AERs was 2.0% (6/300) for gastroscope AERs and 0.8% (1/120) for colonoscope AERs. All the positive cultures, including 6 from gastroscope and 1 from colonoscope AERs, showed monofloral colonization. Of the gastroscope AER samples, 50% (3/6) were colonized by aerobic bacterial and 50% (3/6) by fungal contaminations. CONCLUSION: A full reprocessing cycle of an AER with HLD is adequate for disinfection of the machine. Swab culture is a useful method for monitoring AER decontamination after each reprocessing cycle. Fungal contamination of AERs after reprocessing should also be kept in mind. PMID:22529696

Anti-mycobacteria potential and synergistic effects of combined crude extracts of selected medicinal plants used by Bapedi traditional healers to treat tuberculosis related symptoms in Limpopo Province, South Africa.

PubMed

Komape, Nancy Patience Motlalepula; Bagla, Victor Patrick; Kabongo-Kayoka, Prudence; Masoko, Peter

2017-02-24

Tuberculosis is an infectious communicable disease and the causative agent of the disease has over the years developed resistance to streamline chemotherapeutic agents with dire consequences and there is a need for development of new and more potent alternatives. Constituents of leaves material of Combretum heroroense, Citrus lemon and Apodytes dimidiata were serially extracted using solvents of varying polarity. TLC finger print profile of the different extracts were determined by spraying eluted plates with vanillin sulphuric acid and 2, 2- diphenylpicryl hydrazyl (DPPH) for the presence of antioxidant constituents. Presence of different phytochemicals was determined using standard chemical test. Bioautography was used to determine the number of compounds present in sub-fractions active against Mycobacterium smegmatis. Minimum inhibitory concentration (MIC) values extract and sub-fractions were determined using serial microplate dilution method against M. smegmatis (ATCC 1441), M. tuberculosis (ATCC H37Rv) and multi-drug resistant TB (MDR-TB) field strain. Synergy of the crude extracts of the three plants was determined using microplate dilution method against M. smegmatis. Mass extracted by different solvents was less than 6% dry weight for all the plants. Phlobatannins were not detected in A. dimidiata, C. heroroense and C. lemon as well as cardiac glycosides in C. lemon and A. dimidiata, and saponins in C. heroroense. Sub-fractions of the different plants were shown to contain constituents with antioxidant activity with the highest number detected in C. heroroense. Bioautography results reveal the presence of a compound(s) in the ethyle acetate sub-fraction of C. heroroense and butanol, methanol/water, ethyl acetate and water no.2 subfractions of A. dimidiata, active against M. smegmatis that were not shown to have antioxidant capacity. MIC results for different crude extracts of the three plants against M. smegmatis ranges from 0.1 to 3 mg/ml. The average

Fault block kinematics at a releasing stepover of the Eastern California shear zone: Partitioning of rotation style in and around the Coso geothermal area and nascent metamorphic core complex

NASA Astrophysics Data System (ADS)

Pluhar, Christopher J.; Coe, Robert S.; Lewis, Jonathan C.; Monastero, Francis C.; Glen, Jonathan M. G.

2006-10-01

, K. Richards-Dinger, The Coso geothermal field: a nascent metamorphic core complex, Geol. Soc. Amer. Bull. 117 (2005) 1534-1553.] characterize as a nascent metamorphic core complex. Consistent with upper plate disruption above a detachment, surface rocks (i.e. the upper plate of the detachment system) at the Coso geothermal area are tilted westward. However they appear to exhibit no detectable rotation. Thus, the style of block rotation may be partitioned: with clockwise vertical-axis rotation dominating in the Wild Horse Mesa and horizontal axis rotation (tilting) in the geothermal area.

Trace Gas Measurements in Nascent, Aged and Cloud-processed Smoke from Africa Savanna Fires by Airborne Fourier Transform Infrared Spectroscopy (AFTIR)

NASA Technical Reports Server (NTRS)

Yokelson, Robert J.; Bertschi, Isaac T.; Christian, Ted J.; Hobbs, Peter V.; Ward, Darold E.; Hao, Wei Min

2003-01-01

We measured stable and reactive trace gases with an airborne Fourier transform infrared spectrometer (AFTIR) on the University of Washington Convair-580 research aircraft in August/September 2000 during the SAFARI 2000 dry season campaign in Southern Africa. The measurements included vertical profiles of C02, CO, H20, and CH4 up to 5.5 km on six occasions above instrumented ground sites and below the TERRA satellite and ER-2 high-flying research aircraft. We also measured the trace gas emissions from 10 African savanna fires. Five of these fires featured extensive ground-based fuel characterization, and two were in the humid savanna ecosystem that accounts for most African biomass burning. The major constituents we detected in nascent CH3OOH, HCHO, CH30H, HCN, NH3, HCOOH, and C2H2. These are the first quantitative measurements of the initial emissions of oxygenated volatile organic compounds (OVOC), NH3, and HCN from African savanna fires. On average, we measured 5.3 g/kg of OVOC and 3.6 g/kg of hydrocarbons (including CH4) in the initial emissions from the fires. Thus, the OVOC will have profound, largely unexplored effects on tropical tropospheric chemistry. The HCN emission factor was only weakly dependent on fire type; the average value (0.53 g/kg) is about 20 times that of a previous recommendation. HCN may be useful as a tracer for savanna fires. Delta O3/Delta CO and Delta CH3COO/Delta CO increased to as much as 9% in <1 h of photochemical processing downwind of fires. Direct measurements showed that cloud processing of smoke greatly reduced CH30H, NH3, CH3COOH, SO2, and NO2 levels, but significantly increased HCHO and NO.

Potassium channel openers and prostacyclin play a crucial role in mediating the vasorelaxant activity of Gynura procumbens

PubMed Central

2013-01-01

Background Previous studies of Gynura procumbens (G. procumbens) have shown that partially purified fractions of the leaves are capable of lowering the blood pressure of rats by inhibiting angiotensin-converting enzymic activity and causing vasodilatation. The objectives of this study were therefore to further purify the active compounds that exhibited selective effects on blood vessels, determine the mechanism of actions, and to qualitatively analyse the putative compounds present. Methods The butanolic fraction (BU) of the crude ethanolic extract was purified using column chromatography to obtain several sub-fractions of different polarities. The in vitro effects of BU and the sub-fractions on vascular tension were subsequently determined using isolated rat thoracic aortic rings. The most potent sub-fraction (F1) alone was then investigated for its mechanisms of the vasorelaxant activity. In another experiment, thin-layer chromatography was used to qualitatively analyse the active compounds found in F1. Results The BU and the sub-fractions ranging from 10-7 to 10-2 g/ml significantly (p < 0.05) inhibited the sustained tonic contractions induced by phenylephrine and potassium chloride in a concentration-dependent manner with various degree of potency. The most potent sub-fraction (F1) antagonised the calcium-induced vasocontractions (1 x 10-4 – 1 x 10-2 M) in calcium-free with high concentration of potassium as well as in calcium- and potassium-free Krebs-Henseleit solutions. Contractions induced by noradrenaline and caffeine were not affected by F1. The vasorelaxing effect caused by F1 was significantly attenuated with preincubation of potassium channel blockers (glibenclamide and 4-aminopyridine) and prostacyclin inhibitor (indomethacin) while it was not affected by preincubation with tetraethylammonium, l-nitro-arginine methyl esther, propanolol, atropine, oxadiazolo quinoxalin one and methylene blue. The qualitative phytochemical analysis of F1

Baseline triglyceride levels and insulin sensitivity are major determinants of the increase of LDL particle size and buoyancy induced by rosuvastatin treatment in patients with primary hyperlipidemia.

PubMed

Kostapanos, Michael S; Milionis, Haralampos J; Lagos, Konstantinos G; Rizos, Christos B; Tselepis, Alexandros D; Elisaf, Moses S

2008-08-20

The influence of various statins on low-density-lipoprotein (LDL)-particle phenotype has been reportedly trivial or moderate. We assessed the effect of rosuvastatin (the newest statin available) on the LDL subfraction profile in patients with primary hyperlipidemia. One hundred and twenty patients with primary hyperlipidemia without evidence of cardiovascular disease were randomized to therapeutic lifestyle modification ('control' group, N=60) or therapeutic lifestyle modification plus rosuvastatin 20 mg/day (N=60). Laboratory evaluation was performed at baseline and 12 weeks post-treatment. LDL subfraction analysis was carried out electrophoretically using of high-resolution 3% polyacrylamide gel tubes and the Lipoprint LDL System. Rosuvastatin induced a redistribution of LDL-cholesterol from small-dense LDL particles to large-buoyant ones and increased the mean LDL particle size. This beneficial effect was observed only in patients with baseline triglyceride levels >or=150 mg/dl (mean LDL particle size 255+/-7 A vs 260+/-5 A, P<0.01), whereas the LDL subfraction profile was not altered in those with triglyceride levels <150 mg/dl. Stepwise multivariate linear regression analysis revealed that baseline triglyceride levels (R(2)=0.29, P=0.001) followed by baseline insulin resistance as assessed by the HOmeostasis Model Assessment (HOMA) (R(2)=0.25, P=0.001) were independently associated with the rosuvastatin-induced increase in the mean LDL particle size. In conclusion, rosuvastatin at 20 mg/day favorably modified the relative distribution of LDL-cholesterol distribution on LDL subfractions as well as on the mean LDL particle size in patients treated for primary dyslipidemia. Baseline triglyceride levels as well as baseline HOMA-index were found to be the major predictors of this beneficial action of rosuvastatin.

Flavonoids from artichoke (Cynara scolymus L.) up-regulate endothelial-type nitric-oxide synthase gene expression in human endothelial cells.

PubMed

Li, Huige; Xia, Ning; Brausch, Isolde; Yao, Ying; Förstermann, Ulrich

2004-09-01

Nitric oxide (NO) produced by endothelial nitric-oxide synthase (eNOS) represents an antithrombotic and anti-atherosclerotic principle in the vasculature. Hence, an enhanced expression of eNOS in response to pharmacological interventions could provide protection against cardiovascular diseases. In EA.hy 926 cells, a cell line derived from human umbilical vein endothelial cells (HUVECs), an artichoke leaf extract (ALE) increased the activity of the human eNOS promoter (determined by luciferase reporter gene assay). An organic subfraction from ALE was more potent in this respect than the crude extract, whereas an aqueous subfraction of ALE was without effect. ALE and the organic subfraction thereof also increased eNOS mRNA expression (measured by an RNase protection assay) and eNOS protein expression (determined by Western blot) both in EA.hy 926 cells and in native HUVECs. NO production (measured by NO-ozone chemiluminescence) was increased by both extracts. In organ chamber experiments, ex vivo incubation (18 h) of rat aortic rings with the organic subfraction of ALE enhanced the NO-mediated vasodilator response to acetylcholine, indicating that the up-regulated eNOS remained functional. Caffeoylquinic acids and flavonoids are two major groups of constituents of ALE. Interestingly, the flavonoids luteolin and cynaroside increased eNOS promoter activity and eNOS mRNA expression, whereas the caffeoylquinic acids cynarin and chlorogenic acid were without effect. Thus, in addition to the lipid-lowering and antioxidant properties of artichoke, an increase in eNOS gene transcription may also contribute to its beneficial cardiovascular profile. Artichoke flavonoids are likely to represent the active ingredients mediating eNOS up-regulation.

Globular domain of adiponectin: promising target molecule for detection of atherosclerotic lesions

PubMed Central

Almer, Gunter; Saba-Lepek, Matthias; Haj-Yahya, Samih; Rohde, Eva; Strunk, Dirk; Fröhlich, Eleonore; Prassl, Ruth; Mangge, Harald

2011-01-01

Background: Adiponectin, an adipocyte-specific plasma protein, has been shown to accumulate in injured endothelial cells during development of atherosclerotic lesions. In this study, we investigated the potential of different adiponectin subfractions with special emphasis on globular adiponectin (gAd) to recognize and visualize atherosclerotic lesions. Methods: Recombinant mouse gAd and subfractions of full-length adiponectin (ie, trimeric, hexameric, and oligomeric forms) were fluorescence-labeled. Aortas of wild-type and apoprotein E-deficient mice fed a high cholesterol diet were dissected and incubated with the labeled biomarkers. Imaging was performed using confocal laser scanning microscopy. Results: Confocal laser scanning microscopic images showed that gAd binds more strongly to atherosclerotic plaques than full-length adiponectin subfractions. Further, we showed that gAd accumulates preferentially in endothelial cells and the fibrous cap area of plaques. Here we demonstrate for the first time that gAd recognizes atherosclerotic plaques on aortic sections of apoprotein E-deficient mice. Conclusion: These results suggest that gAd, in addition to its physiological properties, is also suitable as a target molecule for prospective diagnostic strategies in imaging atherosclerotic lesions. PMID:22022204

Electrophoretic separation of kidney and pituitary cells on STS-8

NASA Technical Reports Server (NTRS)

Morrison, D. R.; Nachtwey, D. S.; Barlow, G. H.; Cleveland, C.; Lanham, J. W.; Farrington, M. A.; Hatfield, J. M.; Hymer, W. C.; Grindeland, R.; Lewis, M. L.

1984-01-01

Specific secretory cells were separated from suspensions of cultured primary human embryonic cells and rat pituitary cells in microgravity conditions, with an objective of isolating the subfractions of kidney cells that produce the largest amount of urakinase, and the subfractions of rat pituitary cells that secrete growth hormones (GH), prolactin (PRL), and other hormones. It is inferred from the experimental observations that the surface charge distributions of the GH-containing cells differ from those of the PRL-containing cells, which is explained by the presence of secretory products on the surface of pituitary cells. For kidney cells, the electrophoretic mobility distributions in flight experiments were spread more than the ground controls.

Transfer of subduction fluids into the deforming mantle wedge during nascent subduction: Evidence from trace elements and boron isotopes (Semail ophiolite, Oman)

NASA Astrophysics Data System (ADS)

Prigent, C.; Guillot, S.; Agard, P.; Lemarchand, D.; Soret, M.; Ulrich, M.

2018-02-01

The basal part of the Semail ophiolitic mantle was (de)formed at relatively low temperature (LT) directly above the plate interface during "nascent subduction" (the prelude to ophiolite obduction). This subduction-related LT deformation was associated with progressive strain localization and cooling, resulting in the formation of porphyroclastic to ultramylonitic shear zones prior to serpentinization. Using petrological and geochemical analyses (trace elements and B isotopes), we show that these basal peridotites interacted with hydrous fluids percolating by porous flow during mylonitic deformation (from ∼850 down to 650 °C). This process resulted in 1) high-T amphibole crystallization, 2) striking enrichments of minerals in fluid mobile elements (FME; particularly B, Li and Cs with concentrations up to 400 times those of the depleted mantle) and 3) peridotites with an elevated δ11B of up to +25‰. These features indicate that the metasomatic hydrous fluids are most likely derived from the dehydration of subducting crustal amphibolitic materials (i.e., the present-day high-T sole). The rapid decrease in metasomatized peridotite δ11B with increasing distance to the contact with the HT sole (to depleted mantle isotopic values in <1 km) suggests an intense interaction between peridotites and rapid migrating fluids (∼1-25 m.y-1), erasing the initial high-δ11B subduction fluid signature within a short distance. The increase of peridotite δ11B with increasing deformation furthermore indicates that the flow of subduction fluids was progressively channelized in actively deforming shear zones parallel to the contact. Taken together, these results also suggest that the migration of subduction fluids/melts by porous flow through the subsolidus mantle wedge (i.e., above the plate interface at sub-arc depths) is unlikely to be an effective mechanism to transport slab-derived elements to the locus of partial melting in subduction zones.

Multi-constituent synergism is responsible for anti-inflammatory effect of Azadirachta indica leaf extract.

PubMed

Umar, Muhammad Ihtisham; Asmawi, Mohd Zaini; Sadikun, Amirin; Abdul Majid, A M S; Atangwho, Item Justin; Khadeer Ahamed, Mohamed B; Altaf, Rabia; Ahmad, Ashfaq

2014-11-01

Azadirachta indica A. Juss. (Meliaceaes) leaves have been used traditionally to treat swelling and rheumatism in Indian cultures. To fractionate A. indica leaf extracts using bioactivity guided manner for identification of the active anti-inflammatory principles. Polarity-gradient sequential extracts (petroleum ether, chloroform, methanol, and water) of A. indica leaves were screened for their anti-inflammatory potential using the carrageenan-induced rat paw edema model (1 g/kg). The chloroform extract was sequentially fractionated to obtain n-hexane (F-1), n-hexane-chloroform (F-2), and chloroform (F-3) fractions and their inhibitory effect on rat paw edema was evaluated (500 mg/kg). Inhibitory effect of F-2 on granuloma formation, plasma interleukin (IL-1), and tumor necrosis factor (TNF-α) was assessed at the doses of 100, 200, and 400 mg/kg using the cotton pellet assay in rats. Three sub-fractions (SF-1, SF-2, and SF-3) were obtained upon chromatography of F-2, and their inhibitory effect on cyclooxygenase was assessed at 200 µg/mL concentration. The sub-fractions were subjected to gas chromatography-mass spectrometry (GC-MS). All the extracts showed significant anti-inflammatory effect; however, chloroform extract was the most effective against paw edema (53.25% inhibition). The three fractions of chloroform extract showed significant effect, while F-2 being the most potent (51.02%). F-2 demonstrated dose-dependent inhibition of granuloma and cytokines. Interestingly, all the sub-fractions of F-2 inhibited COX-1 and COX-2 with almost equal potential. GC-MS revealed that chemically the sub-fractions were totally different from each other. Anti-inflammatory effect of A. indica is a result of cumulative and synergistic effects of diversified constituents with varying polarities that collectively exert the effect via suppression of cyclo-oxygenases and cytokines (IL-1 and TNF-α).

Molecular mechanism and structure of Trigger Factor bound to the translating ribosome

PubMed Central

Merz, Frieder; Boehringer, Daniel; Schaffitzel, Christiane; Preissler, Steffen; Hoffmann, Anja; Maier, Timm; Rutkowska, Anna; Lozza, Jasmin; Ban, Nenad; Bukau, Bernd; Deuerling, Elke

2008-01-01

Ribosome-associated chaperone Trigger Factor (TF) initiates folding of newly synthesized proteins in bacteria. Here, we pinpoint by site-specific crosslinking the sequence of molecular interactions of Escherichia coli TF and nascent chains during translation. Furthermore, we provide the first full-length structure of TF associated with ribosome–nascent chain complexes by using cryo-electron microscopy. In its active state, TF arches over the ribosomal exit tunnel accepting nascent chains in a protective void. The growing nascent chain initially follows a predefined path through the entire interior of TF in an unfolded conformation, and even after folding into a domain it remains accommodated inside the protective cavity of ribosome-bound TF. The adaptability to accept nascent chains of different length and folding states may explain how TF is able to assist co-translational folding of all kinds of nascent polypeptides during ongoing synthesis. Moreover, we suggest a model of how TF's chaperoning function can be coordinated with the co-translational processing and membrane targeting of nascent polypeptides by other ribosome-associated factors. PMID:18497744

Nascent Genomic Evolution and Allopatric Speciation of Myroides profundi D25 in Its Transition from Land to Ocean.

PubMed

Zhang, Yu-Zhong; Li, Yi; Xie, Bin-Bin; Chen, Xiu-Lan; Yao, Qiong-Qiong; Zhang, Xi-Ying; Kempher, Megan L; Zhou, Jizhong; Oren, Aharon; Qin, Qi-Long

2016-01-12

A large amount of bacterial biomass is transferred from land to ocean annually. Most transferred bacteria should not survive, but undoubtedly some do. It is unclear what mechanisms these bacteria use in order to survive and even thrive in a new marine environment. Myroides profundi D25(T), a member of the Bacteroidetes phylum, was isolated from deep-sea sediment of the southern Okinawa Trough near the China mainland and had high genomic sequence identity to and synteny with the human opportunistic pathogen Myroides odoratimimus. Phylogenetic and physiological analyses suggested that M. profundi recently transitioned from land to the ocean. This provided an opportunity to explore how a bacterial genome evolved to survive in a novel environment. Changes in the transcriptome were evaluated when both species were cultured under low-salinity conditions and then transferred to high-salinity conditions. Comparative genomic and transcriptomic analyses showed that M. profundi altered transcription regulation in the early stages of survival. In these stages, vertically inherited genes played a key role in the survival of M. profundi. The contribution of M. profundi unique genes, some possibly acquired by horizontal gene transfer (HGT), appeared relatively small, and expression levels of unique genes were diminished under the high-salinity conditions. We postulate that HGT genes might play an important role in longer-term adaptation. These results suggested that some human pathogens might have the ability to survive in and adapt to the marine environment, which may have important implications for public health control in coastal regions. Horizontal gene transfer (HGT) is considered to be important for bacteria to adapt to a different microhabitat. However, our results showed that vertically inherited genes might play more important roles than HGT genes in the nascent adaptation to the marine environment in the bacterium Myroides profundi, which has recently been

Lipoprotein-Cholesterol Fractions in Marginalized Roma versus Majority Population.

PubMed

Hubková, Beáta; Bódy, Gabriel; Mašlanková, Jana; Birková, Anna; Frišman, Eugen; Kraus, Vladimír; Mareková, Mária

2018-01-06

The trend of modern clinical biochemistry is to emphasize the composition and the quality of lipoproteins over their quantity. The serum lipoprotein fractions and subfractions were analyzed by the Lipoprint Lipoprotein Subfractions Testing System, the parameters of lipid profile, as total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and triacylglycerides (TAG) were determined by an automated selective biochemical analyzer. Our results showed a significantly lower concentration of cholesterol in the LDL fractions 1 and 2 and in the HDL fractions 8 to 10 in Roma compared to the majority population. The most significant differences between Roma and the majority population when considering body mass index (BMI), waist-to-hip ratio and the index of central obesity were in very low-density lipoproteins (VLDL), intermediate-density lipoproteins, fraction A (IDL-A) and LDL-2. The last two listed were significantly higher in the majority population. VLDL was significantly higher in overweight or obese Roma men and in Roma men with central obesity compared to men from the majority population, as well as in Roma women with normal weight and physiological waist-to-hip ratio compared to the women from majority population. Our study is among the first describing the distribution of lipoprotein subfractions in different ethnic groups.

The red wine extract-induced activation of endothelial nitric oxide synthase is mediated by a great variety of polyphenolic compounds.

PubMed

Auger, Cyril; Chaabi, Mehdi; Anselm, Eric; Lobstein, Annelise; Schini-Kerth, Valérie B

2010-07-01

Phenolic extracts from red wine (RWPs) have been shown to induce nitric oxide (NO)-mediated vasoprotective effects, mainly by causing the PI3-kinase/Akt-dependent activation of endothelial NO synthase (eNOS). RWPs contain several hundreds of phenolic compounds. The aim of the present study was to identify red wine phenolic compounds capable of activating eNOS in endothelial cells using multi-step fractionation. The red wine phenolic extract was fractionated using Sephadex LH-20 and preparative RP-HPLC approaches. The ability of a fraction to activate eNOS was assessed by determining the phosphorylation level of Akt and eNOS by Western blot analysis, and NO formation by electron spin resonance spectroscopy. Tentative identification of phenolic compounds in fractions was performed by MALDI-TOF and HPLC-MS techniques. Separation of RWPs by Sephadex LH-20 generated nine fractions (fractions A to I), of which fractions F, G, H and I caused significant eNOS activation. Fraction F was then subjected to semi-preparative RP-HPLC to generate ten subfractions (subfraction SF1 to SF10), all of which caused eNOS activation. The active fractions and subfractions contained mainly procyanidins and anthocyanins. Isolation of phenolic compounds from SF9 by semi-preparative RP-HLPC lead to the identification of petunidin-O-coumaroyl-glucoside as a potent activator of eNOS.

Structures of Phytosterols and Triterpenoids with Potential Anti-Cancer Activity in Bran of Black Non-Glutinous Rice

PubMed Central

Suttiarporn, Panawan; Chumpolsri, Watcharapong; Mahatheeranont, Sugunya; Luangkamin, Suwaporn; Teepsawang, Somsuda; Leardkamolkarn, Vijittra

2015-01-01

Structures of some bioactive phytochemicals in bran extract of the black rice cv. Riceberry that had demonstrated anti-cancer activity in leukemic cell line were investigated. After saponification with potassium hydroxide, separation of the unsaponified fraction by reversed-phase high performance liquid chromatography (HPLC) resulted in four sub-fractions that had a certain degree of anti-proliferation against a mouse leukemic cell line (WEHI-3 cell), this being IC50 at 24 h ranging between 2.80–467.11 μg/mL. Further purification of the bioactive substances contained in these four sub-fractions was performed by normal-phase HPLC. Structural characterization by gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance spectroscopy (NMR) resulted in, overall, the structures of seven phytosterols and four triterpenoids. Four phytosterols, 24-methylene-ergosta-5-en-3β-ol, 24-methylene-ergosta-7-en-3β-ol, fucosterol, and gramisterol, along with three triterpenoids, cycloeucalenol, lupenone, and lupeol, were found in the two sub-fractions that showed strong anti-leukemic cell proliferation (IC50 = 2.80 and 32.89 μg/mL). The other sterols and triterpenoids were campesterol, stigmasterol, β-sitosterol and 24-methylenecycloartanol. Together with the data from in vitro biological analysis, we suggest that gramisterol is a significant anti-cancer lead compound in Riceberry bran extract. PMID:25756784

Antitumour and apoptotic effects of a novel Tris-peptide complex obtained after isolation of Raoultella ornithinolytica extracellular metabolites.

PubMed

Fiołka, M J; Grzywnowicz, K; Rzymowska, J; Lewtak, K; Szewczyk, R; Mendyk, E; Keller, R

2015-06-01

The characterization of the antitumour activity and chemical identification of the compounds obtained after the isolation of extracellular metabolites of bacteria Raoultella ornithinolytica. The fraction with anticancer activity against the HeLa cell line, T47D and TOV-112D was obtained from the supernatants of R. ornithinolytica culture using ion-exchange chromatography, and separated by Sephadex G-50 medium gel filtration into two subfractions. The obtained compounds were analysed using Fourier Transform-Infrared Spectroscopy, Raman spectroscopy and matrix-assisted laser desorption/ionization MS/MS spectrometry. The antitumour activity of the two subfractions was analysed using 5-bromo-2-deoxy-uridine kit. The subfraction with the highest activity against HeLa cells was identified as Tris-peptide complex. The amino acid sequence of the peptide from the complex was found to be TDAPSFSDIPN and molecular weight was estimated at 1430·6576 Da. Cytotoxic, cytopathic and apoptotic effects in HeLa cells treated with the active complex were observed; however, the cytotoxic effect against normal human skin fibroblasts was minimal. The Tris-peptide complex from R. ornithinolytica showed selective antitumour activity against the HeLa cell line. The Tris-peptide complex due to the high selectivity can be used in biomedicine, and its derivatives may contribute to the development of new anticancer compounds. © 2015 The Society for Applied Microbiology.

Antioxidant, Anti-inflammatory, Analgesic Properties, and Phytochemical Characterization of Stem Bark Extract and Fractions of Anthocleista nobilis

PubMed Central

Ngwoke, Kenneth Gerald; Akwagbulam, Amaka Godsaveus; Erhirhie, Ernest Oghenesuvwe; Ajaghaku, Daniel Lotanna; Okoye, Festus Basden Chiedu; Esimone, Charles Okechukwu

2018-01-01

Background: Anthocleista nobilis (Loganiaceae) is used by Mbano people of Imo State, Nigeria, for the treatment of various ailments Objective: The aim of this study is to evaluate the antioxidant, anti-inflammatory, and analgesic properties of the methanol extract, fractions, and subfractions of A. nobilis. Materials and Methods: The powdered stem bark was extracted with methanol and sequentially fractionated into n-hexane, ethyl acetate, and butanol fractions. The constituents of the fractions were analyzed using high-pressure liquid chromatography (HPLC), and the components were identified by dereplication. Antioxidant potential of the extracts and fractions was investigated using 2,2-diphenyl-1-picrylhydrazyl free-radical scavenging method. Anti-inflammatory and analgesic activities of the extract and fractions were also investigated using xylene-induced inflammation and acetic acid-induced writhing models, respectively. Results: A total of five compounds isovitexin (Rt = 18.77 min), isovitexin-2''-O-xyl (Rt = 19.68 min), p-Hydroxybenzoic acid (Rt = 11.88 min), Sarasinoside L (Rt = 19.64 min), isovitexin (Rt = 18.77), and apigenin monoglycoside (Rt = 19.64 min) were identified by HPLC analysis and dereplication. The ethyl acetate fraction and subfraction elicited the best anti-inflammatory activity. The ethyl acetate subfraction also inhibited acetic acid-induced pain by 79% and 85.0% at the doses of 100 mg/kg and 200 mg/kg, respectively, which was better than 71.1% and 81.3% observed for diclofenac at similar doses. Conclusion: A. nobilis could be a potential source of anti-inflammatory and analgesic lead compounds. SUMMARY The extract, fractions and subfractions of Anthocleista nobilis were screened or antioxidant, anti-inflammatory and Analgesic properties in vitro and in mice models. Some of the components were identified by dereplication after HPLC analysis. The results demonstrated potent anti-inflammatory and analgesic property of the extracts and

Antioxidant, Anti-inflammatory, Analgesic Properties, and Phytochemical Characterization of Stem Bark Extract and Fractions of Anthocleista nobilis.

PubMed

Ngwoke, Kenneth Gerald; Akwagbulam, Amaka Godsaveus; Erhirhie, Ernest Oghenesuvwe; Ajaghaku, Daniel Lotanna; Okoye, Festus Basden Chiedu; Esimone, Charles Okechukwu

2018-01-01

Anthocleista nobilis ( Loganiaceae ) is used by Mbano people of Imo State, Nigeria, for the treatment of various ailments. The aim of this study is to evaluate the antioxidant, anti-inflammatory, and analgesic properties of the methanol extract, fractions, and subfractions of A. nobilis . The powdered stem bark was extracted with methanol and sequentially fractionated into n-hexane, ethyl acetate, and butanol fractions. The constituents of the fractions were analyzed using high-pressure liquid chromatography (HPLC), and the components were identified by dereplication. Antioxidant potential of the extracts and fractions was investigated using 2,2-diphenyl-1-picrylhydrazyl free-radical scavenging method. Anti-inflammatory and analgesic activities of the extract and fractions were also investigated using xylene-induced inflammation and acetic acid-induced writhing models, respectively. A total of five compounds isovitexin ( R t = 18.77 min), isovitexin-2''-O-xyl ( R t = 19.68 min), p-Hydroxybenzoic acid ( R t = 11.88 min), Sarasinoside L ( R t = 19.64 min), isovitexin ( R t = 18.77), and apigenin monoglycoside ( R t = 19.64 min) were identified by HPLC analysis and dereplication. The ethyl acetate fraction and subfraction elicited the best anti-inflammatory activity. The ethyl acetate subfraction also inhibited acetic acid-induced pain by 79% and 85.0% at the doses of 100 mg/kg and 200 mg/kg, respectively, which was better than 71.1% and 81.3% observed for diclofenac at similar doses. A. nobilis could be a potential source of anti-inflammatory and analgesic lead compounds. The extract, fractions and subfractions of Anthocleista nobilis were screened or antioxidant, anti-inflammatory and Analgesic properties in vitro and in mice models. Some of the components were identified by dereplication after HPLC analysis. The results demonstrated potent anti-inflammatory and analgesic property of the extracts and fractions. The dereplication analysis also identified vitexin and

Pitavastatin 4 mg Provides Significantly Greater Reduction in Remnant Lipoprotein Cholesterol Compared With Pravastatin 40 mg: Results from the Short-term Phase IV PREVAIL US Trial in Patients With Primary Hyperlipidemia or Mixed Dyslipidemia.

PubMed

Miller, P Elliott; Martin, Seth S; Joshi, Parag H; Jones, Steven R; Massaro, Joseph M; D'Agostino, Ralph B; Sponseller, Craig A; Toth, Peter P

2016-03-01

Remnants are partially hydrolyzed, triglyceride-rich lipoproteins that are implicated in atherosclerosis. We assessed the adequacy of pitavastatin 4 mg and pravastatin 40 mg in reducing atherogenic lipid parameters beyond LDL-C, in particular remnant lipoprotein cholesterol (RLP-C). From the Phase IV, multicenter, randomized, double-blind PREVAIL US (A Study of Pitavastatin 4 mg Vs. Pravastatin 40 mg in Patients With Primary Hyperlipidemia or Mixed Dyslipidemia) trial, we examined lipoprotein cholesterol subfractions using Vertical Auto Profile testing and apolipoproteins B and A-I at baseline and 12 weeks. Participants with primary hyperlipidemia or mixed dyslipidemia had LDL-C levels of 130 to 220 mg/dL and triglyceride levels ≤ 400 mg/dL. In this post hoc analysis, changes in lipid parameters were compared by using ANCOVA. Lipoprotein subfraction data were available in 312 patients (pitavastatin, n = 157; pravastatin, n = 155). Pitavastatin promoted a greater reduction in RLP-C than pravastatin (-13.6 [8.7] vs -9.3 [9.5] mg/dL). Furthermore, the pitavastatin group reported greater reductions in both components of RLP-C (both, P < 0.001): intermediate-density lipoprotein cholesterol (-9.5 [6.3] vs -6.4 [6.6] mg/dL) and very low-density lipoprotein cholesterol subfraction 3 (-4.1 [3.5] vs -2.9 [3.8] mg/dL). There were also greater reductions in the major ratios of risk (apolipoprotein B/apolipoprotein A-I and total cholesterol/HDL-C) (both, P < 0.001). There were no significant changes in HDL-C, its subfractions, or natural log lipoprotein(a)-cholesterol. The mean age was 58.8 ± 8.9 years in the pitavastatin group and 57.0 ± 10.2 years in the pravastatin group. Compared with pravastatin 40 mg daily, pitavastatin 4 mg provided superior reductions in atherogenic lipid parameters beyond LDL-C, including RLP-C. Future studies are needed investigate the clinical implications of lowering directly measured RLP-C as the principal target. ClinicalTrials.gov identifier

Low density lipoprotein fraction assay for cardiac disease risk

DOEpatents

Krauss, Ronald M.; Blanche, Patricia J.; Orr, Joseph

1999-01-01

A variable rate density gradient electrophoric gel is described which separate LDL subfractions with the precision of ultracentrifugation techniques. Also, an innovative bottom inlet mixing chamber particularly useful for producing these gels is described.

Low density lipoprotein fraction assay for cardiac disease risk

DOEpatents

Krauss, R.M.; Blanche, P.J.; Orr, J.

1999-07-20

A variable rate density gradient electrophoric gel is described which separates LDL subfractions with the precision of ultracentrifugation techniques. Also, an innovative bottom inlet mixing chamber particularly useful for producing these gels is described. 8 figs.

Antifungal Properties of Crude Extracts, Fractions, and Purified Compounds from Bark of Curatella americana L. (Dilleniaceae) against Candida Species

PubMed Central

Mendes de Toledo, Cleyton Eduardo; Santos, Patrícia Regina; Palazzo de Mello, João Carlos; Dias Filho, Benedito Prado; Ueda-Nakamura, Tânia

2015-01-01

The ethnomedicinal plant Curatella americana L. (Dilleniaceae) is a common shrub in the Brazilian cerrado, in which crude extract showed antifungal activity in a preliminary study. In this work, the antifungal and cytotoxic properties of the crude extract, fractions, and isolated compounds from C. americana were evaluated against the standard yeast strains Candida albicans, C. tropicalis, and C. parapsilosis, clinical isolates, and fluconazole-resistant strains. The combinatory effects between subfractions and isolated compounds and effects on cell morphology, virulence factors, and exogenous ergosterol were also evaluated. The MIC obtained against the Candida species including fluconazole-resistant strain ranged from 15.3 to 31.3 µg/mL for crude extract, 3.9 to 15.6 µg/mL for ethyl acetate fraction, and 7.8 to 31.3 µg/mL for subfractions. The isolated compounds identified as 4′-O-methyl-catechin, epicatechin-3-O-gallate, and 4′-O-methyl-catechin-3-O-gallate showed lower antifungal activity than the crude extract and fractions (MIC ranging from 31.3 to 125.0 µg/mL). The addition of exogenous ergosterol to yeast culture did not interfere in the antifungal activity of the extract and its fractions. Synergistic antifungal activity was observed between subfractions and isolated compounds. The effects on virulence factors and the different mechanisms of action compared to fluconazole and nystatin suggest that this ethnomedicinal plant may be an effective alternative treatment for candidiasis. PMID:26347790

Radiometric assay for ganglioside sialidase applied to the determination of the enzyme subcellular location in culture human fibroblasts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chigorno, V.; Cardace, G.; Pitto, M.

1986-03-01

A radiometric method for the assay of ganglioside sialidase in cultured human fibroblasts was set up. As substrate, highly radioactive (1.28 Ci/mmol) ganglioside GD/sub 1a/ isotopically tritium-labeled at carbon C-3 of the long chain base was employed; the liberated, and TLC separated (/sup 3/H)GM/sub 1/ was determined by computer-assisted radiochromatoscanning. Under experimental conditions that provided a low and quite acceptable (4-5%) coefficient of variation, the detection limit of the method was 0.1 nmol of liberated GM/sub 1/, using as low as 10 ..mu..g of fibroblast homogenate as protein. The detection limit could be lowered to 0.02-0.03 nmol, adopting conditions that,more » however, carried a higher analytical error (coefficient of variation over 10%). The content of ganglioside sialidase in human fibroblasts cultured in 75-cm/sup 2/ plastic flasks was 5.8 -/+ 2.5 (SD) nmol liberated GM/sub 1/ h/sup -1/ mg protein/sup -1/. Subfractionation studies performed on fibroblast homogenate showed that the ganglioside sialidase was mainly associated with the light membrane subfraction that was rich in plasma and intracellular membranes. This subfraction displayed almost no sialidase activity on the artificial substrate 4-methylumbelliferyl-D-N-acetylneuraminic acid. A small but measurable ganglioside sialidase activity was also present in the lysosome-enriched subfraction, which contained a very high sialidase activity on the above artificial substrate.« less

Effects of prescription niacin and omega-3 fatty acids on lipids and vascular function in metabolic syndrome: a randomized controlled trial[S

PubMed Central

Shearer, Gregory C.; Pottala, James V.; Hansen, Susan N.; Brandenburg, Verdayne; Harris, William S.

2012-01-01

The metabolic syndrome includes both dyslipidemia and impaired vascular function. Because extended-release niacin (ERN) and prescription omega-3 acid ethyl-esters (P-OM3) independently improve these characteristics, we tested their effects in combination. Sixty metabolic syndrome subjects were randomized to 16 weeks of treatment on dual placebo, P-OM3 (4g/day), ERN (2 g/day), or combination in a double-blind trial. Lipoprotein subfractions and vascular endpoints were measured and tested using ANCOVA. ERN increased HDL cholesterol by 5.4 mg/dl from baseline (P = 0.04), decreased triglycerides (TG) by 39 mg/dl (−21%, P = 0.003), and decreased the augmentation index, which is a measure of vascular stiffness, by 3.5 units (P = 0.04). P-OM3 reduced TG by 26 mg/dl (−13%, P = 0.04). Combination treatment increased HDL cholesterol by 7.8 mg/dl (P = 002) and decreased TG by 72 mg/dl (−34%) but there was no improvement in vascular stiffness. Detailed analysis of lipoprotein subfractions revealed increased large, bouyant HDL2 (3.3 mg/dl; P = 0.002) and decreased VLDL1+2 (−32%; P < 0.0001), among subjects treated with combination therapy, that were not present with either therapy alone. ERN and P-OM3 alone improved characteristics of metabolic syndrome; however, whereas subjects on combination therapy did not have improved vascular stiffness, TG and HDL levels improved as did certain lipoprotein subfractions. PMID:22892157

Identification of (Z)-2,3-Diphenylacrylonitrile as Anti-Cancer Molecule in Persian Gulf Sea Cucumber Holothuria parva

PubMed Central

Amidi, Salimeh; Hashemi, Zahra; Motallebi, Abbasali; Nazemi, Melika; Farrokhpayam, Hoda; Seydi, Enayatollah

2017-01-01

Hepatocellular carcinoma (HCC), also named cancerous hepatoma, is the most common type of malignant neoplasia of the liver. In this research, we screened the Persian Gulf sea cucumber Holothuria parva (H. parva) methanolic sub-fractions for the possible existence of selective toxicity on liver mitochondria isolated from an animal model of HCC. Next, we purified the most active fraction. Thus the structure of the active molecule was identified. HCC was induced by diethylnitrosamine (DEN) and 2-acetylaminofluorene (2-AAF) protocol. Rat liver mitochondria for evaluation of the selective cytotoxic effects of sub-fractions of H. parva were isolated and then mitochondrial parameters were determined. Our results showed that C1 sub-fraction of methanolic extract of H. parva considerably increased reactive oxygen species (ROS) generation, collapse of mitochondrial membrane potential (MMP), swelling in mitochondria and cytochrome c release only on HCC liver mitochondria. Furthermore, the methanolic extract of H. parva was investigated furthermore and the active fraction was extracted. In this fraction, (Z)-2,3-diphenylacrylonitrile molecule, which is also known as α-cyanostilbene, was identified by mass analysis. This molecule increased ROS generation, collapse of MMP, swelling in mitochondria and finally cytochrome c release only on HCC liver mitochondria. The derivatives of (Z)-2,3-diphenylacrylonitrile in other natural products were also reported as an anti-cancer agent. These results suggest the eligibility of the (Z)-2,3-diphenylacrylonitrile as a complementary therapeutic agent for patients with HCC. PMID:29035293

SINTERING OF NASCENT CALCIUM OXIDE

EPA Science Inventory

The paper discusses the measurement of the sintering rate of CaO in a nitrogen atmosphere at temperatures of 700-1100 C. CaO prepared from ultrapure CaCO3 was compared with an impure CaO derived from limestone. Both materials yielded an initial surface area of 104 sq m/g. The rat...

[SPECTRAL AND ACID-BASE PROPERTIES OF HEMOLYMPH PLASMA AND ITS FRACTIONS FROM GASTROPOD PULMONATE MOLLUSC ACHATINA FULICA].

PubMed

Petrova, T A; Lianguzov, A Yu; Malygina, N M

2016-01-01

The set of normal biochemical indicators of the hemolymph plasma of gastropod pulmonate mollusc Achatinafulica is described. Comparative analysis of the whole plasma and its subfractions enriched and depleted of oxygen-carrying protein hemocyanin was performed by spectrophotometry and spectrofluorimetry methods. Individual features of the absorption spectra were analyzed using fourth derivatives. The optimum method for estimating protein concentration was chosen. To characterize acid-base properties of plasma hemolymph and its sub-fractions we calculated buffer capacity, equivalence points and pK values of dominant buffer groups. It is shown that the major role in maintaining the buffer capacity of hemolymph belongs to the bicarbonate system. These results are compared with data for Helix pomatia available in literature. In the future the indicators studied in this work will be used to develop ecotoxicological criteria for the environmental assessment.

Thermodynamics and kinetics of protein folding on the ribosome: Alteration in energy landscapes, denatured state, and transition state ensembles

NASA Astrophysics Data System (ADS)

O'Brien, Edward; Vendruscolo, Michele; Dobson, Christopher

2010-03-01

In vitro experiments examining cotranslational folding utilize ribosome-nascent chain complexes (RNCs) in which the nascent chain is stalled at different points of its biosynthesis on the ribosome. We investigate the thermodynamics, kinetics, and structural properties of RNCs containing five different globular and repeat proteins stalled at ten different nascent chain lengths using coarse grained replica exchange simulations. We find that when the proteins are stalled near the ribosome exit tunnel opening they exhibit altered folding coopserativity, quantified by the van't Hoff enthalpy criterion; a significantly altered denatured state ensemble, in terms of Rg and shape parameters (Rg tensor); and the appearance of partially folded intermediates during cotranslation, evidenced by the appearance of a third basin in the free energy profile. These trends are due in part to excluded volume (crowding) interactions between the ribosome and nascent chain. We perform in silico temperature-jump experiments on the RNCs and examine nascent chain folding kinetics and structural changes in the transition state ensemble at various stall lengths.

Regulation of low-density lipoprotein subfractions by carbohydrates.

PubMed

Gerber, Philipp A; Berneis, Kaspar

2012-07-01

This article aims at reviewing the recent findings that have been made concerning the crosstalk of carbohydrate metabolism with the generation of small, dense low-density lipoprotein (LDL) particles, which are known to be associated with an adverse cardiovascular risk profile. Studies conducted during the past few years have quite unanimously shown that the quantity of carbohydrates ingested is associated with a decrease of LDL particle size and an increase in its density. Conversely, diets that aim at a reduction of carbohydrate intake are able to improve LDL quality. Furthermore, a reduction of the glycaemic index without changing the amount of carbohydrates ingested has similar effects. Diseases with altered carbohydrate metabolism, for example, type 2 diabetes, are associated with small, dense LDL particles. Finally, even the kind of monosaccharide the carbohydrate intake consists of is important concerning LDL particle size: fructose has been shown to alter the LDL particle subclass profile more adversely than glucose in many recent studies. LDL particle quality, rather than its quantity, is affected by carbohydrate metabolism, which is of clinical importance, in particular, in the light of increased carbohydrate consumption in today's world.

Anti-Lymphocyte Antibodies: Specifically Purified Anti-Thymocyte Antibody as an Immunosuppressive Agent in Human and Rhesus Transplants.

DTIC Science & Technology

To further isolate the immunosuppressive fraction of antithymocyte antibody, the mouse skin graft system has been developed to test subfractions. The technique of Billingham is used to skin graft between the A/J-C3H strains of mice. Antimouse

Genome-wide association study indicates variants associated with insulin signaling and inflammation mediate lipoprotein responses to fenofibrate

USDA-ARS?s Scientific Manuscript database

A shift towards overall larger very low-density lipoprotein (VLDL), and smaller low-density lipoprotein and high-density lipoprotein (HDL) diameters occurs in insulin resistance (IR), which reflects shifts in the distribution of the subfraction concentrations. Fenofibrate, indicated for hypertriglyc...

Cardiovascular risk in systemic lupus erythematosus--evidence of increased oxidative stress and dyslipidaemia.

PubMed

Nuttall, S L; Heaton, S; Piper, M K; Martin, U; Gordon, C

2003-06-01

Systemic lupus erythematosus (SLE) is associated with severe and premature cardiovascular disease, which is not explained by traditional risk factors alone. This study aimed to investigate markers of oxidative stress, lipid metabolism and inflammation as potential cardiovascular risk factors in women with SLE. Venous blood samples were taken from 53 female Caucasian patients with SLE and from healthy age- and sex-matched controls. Samples were analysed for markers of oxidative stress, lipid metabolism [including low-density lipoprotein (LDL) subfraction profile] and C-reactive protein (CRP). Female SLE patients had an atherogenic lipid profile characterized by raised total cholesterol and triglycerides, and the presence of small, dense LDL subfractions compared with healthy controls. These changes were associated with increased oxidative damage and a moderately raised CRP. The results provide evidence for free radical and inflammatory activity in SLE and suggest potential targets to reduce the risk of cardiovascular disease in these patients.

Determination of bioactivity of chemical fractions of liquid wastes using freshwater and saltwater algae and crustaceans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walsh, G.E.; Garnas, R.L.

1983-03-01

Complex wastes from industrial and municipal outfalls were fractionated chemically and tested for toxicity with freshwater and saltwater algae and crustaceans. The organic fraction of each waste was subfractionated into acid-, base-, and neutral-extractable portions, and the inorganic fraction was subfractionated into its anion and cation components. All wastes affected growth of the algae Skeletonema costatum (saltwater) and Monoraphidium capricornutum (freshwater) or survival of Mysidopsis bahia (saltwater) and Daphnia magna (freshwater). Usually, bioactivity was limited to one or two subfractions. In some cases, algal growth was stimulated by a fraction or subfraction, whereas stimulation was not detected in whole waste.more » It is suggested that fractionation must be done in order to estimate the full potential impact of complex wastes on aquatic systems. The method can also be used to identify toxic factors before application of cost-effective control technology.« less

The Effect of Exercise Training on Serum Lipids in the Elderly.

PubMed

Ades, Philip A.; Poehlman, Eric T.

1996-10-01

Numerous intervention trials in young subjects suggest that aerobic exercise training exerts favorable effects on specific lipid subfractions, in particular serum triglycerides and high density lipoprotein (HDL) cholesterol. Cross sectional studies in older individuals suggest that active individuals have more favorable lipid profiles than inactive individuals. However, it remains controversial as to whether leisure time activity or fitness levels per se are independent predictors of lipid measures in the elderly versus their intermediate effects on body composition and body fat distribution. That is, a greater deposition of abdominal fat in the least fit individuals is associated with adverse lipid profiles. Short-term (8-weeks) aerobic exercise in elders is not associated with any significant changes in lipid profiles, however, longer term programs, particularly if associated with improvements in body fat distribution and/or weight loss, have been demonstrated to yield significant improvements in lipid subfractions, in particular triglycerides and HDL cholesterol.

The isolation and subfractionation of plasma membrane from the cellular slime mould Dictyostelium discoideum

PubMed Central

Green, Anita A.; Newell, Peter C.

1974-01-01

A procedure for the isolation and separation of three different subfractions of plasma membrane from the cellular slime mould Dictyostelium discoideum is described. The cells were disrupted by freeze-thawing in liquid N2 and plasma membranes were purified by equilibrium centrifugation in a sucrose gradient. The cell surface was labelled with radioactive iodide by using the lactoperoxidase iodination method. Alkaline phosphatase was identified as a plasma-membrane marker by its co-distribution with [125I]iodide. 5′-Nucleotidase, which has been widely described as a plasma-membrane marker enzyme in mammalian tissues, was not localized to any marked extent in D. discoideum plasma membrane. The isolated plasma membranes showed a 24-fold enrichment of alkaline phosphatase specific activity relative to the homogenate and a yield of 50% of the total plasma membranes. Determination of succinate dehydrogenase and NADPH–cytochrome c reductase activities indicated that the preparation contained 2% of the total mitochondria and 3% of the endoplasmic reticulum. When the plasma-membrane preparation was further disrupted in a tight-fitting homogenizer, three plasma-membrane subfractions of different densities were obtained by isopycnic centrifugation. The enrichment of alkaline phosphatase was greatest in the subfraction with the lowest density. This fraction was enriched 36-fold relative to the homogenate and contained 19% of the total alkaline phosphatase activity but only 0.08% of the succinate dehydrogenase activity and 0.34% of the NADPH–cytochrome c reductase activity. Electron microscopy of this fraction showed it to consist of smooth membrane vesicles with no recognizable contaminants. ImagesPLATE 1 PMID:4156170

Cucumis sativus Aqueous Fraction Inhibits Angiotensin II-Induced Inflammation and Oxidative Stress In Vitro.

PubMed

Trejo-Moreno, Celeste; Méndez-Martínez, Marisol; Zamilpa, Alejandro; Jiménez-Ferrer, Enrique; Perez-Garcia, Maria Dolores; Medina-Campos, Omar N; Pedraza-Chaverri, José; Santana, María Angélica; Esquivel-Guadarrama, Fernando R; Castillo, Aida; Cervantes-Torres, Jacquelynne; Fragoso, Gladis; Rosas-Salgado, Gabriela

2018-02-28

Inflammation and oxidative stress play major roles in endothelial dysfunction, and are key factors in the progression of cardiovascular diseases. The aim of this study was to evaluate in vitro the effect of three subfractions (SFs) from the Cucumis sativus aqueous fraction to reduce inflammatory factors and oxidative stress induced by angiotensin II (Ang II) in human microvascular endothelial cells-1 (HMEC-1) cells. The cells were cultured with different concentrations of Ang II and 0.08 or 10 μg/mL of SF1, SF2, or SF3, or 10 μmol of losartan as a control. IL-6 (Interleukin 6) concentration was quantified. To identify the most effective SF combinations, HMEC-1 cells were cultured as described above in the presence of four combinations of SF1 and SF3. Then, the effects of the most effective combination on the expression of adhesion molecules, the production of reactive oxygen species (ROS), and the bioavailability of nitric oxide (NO) were evaluated. Finally, a mass spectrometry analysis was performed. Both SF1 and SF3 subfractions decreased the induction of IL-6 by Ang II, and C4 (SF1 and SF3, 10 μg/mL each) was the most effective combination to inhibit the production of IL-6. Additionally, C4 prevented the expression of adhesion molecules, reduced the production of ROS, and increased the bioavailability of NO. Glycine, arginine, asparagine, lysine, and aspartic acid were the main components of both subfractions. These results demonstrate that C4 has anti-inflammatory and antioxidant effects.

Effect of exercise training on plasma levels and functional properties of high-density lipoprotein cholesterol in the metabolic syndrome.

PubMed

Casella-Filho, Antonio; Chagas, Antonio Carlos P; Maranhão, Raul C; Trombetta, Ivani C; Cesena, Fernando H Y; Silva, Vanessa M; Tanus-Santos, Jose Eduardo; Negrão, Carlos E; da Luz, Protasio L

2011-04-15

Intense lifestyle modifications can change the high-density lipoprotein (HDL) cholesterol concentration. The aim of the present study was to analyze the early effects of short-term exercise training, without any specific diet, on the HDL cholesterol plasma levels and HDL functional characteristics in patients with the metabolic syndrome (MS). We studied 30 sedentary subjects, 20 with and 10 without the MS. The patients with the MS underwent moderate intensity exercise training for 3 months on bicycle ergometers. Blood was sampled before and after training for biochemical analysis, paraoxonase-1 activity, and HDL subfraction composition and antioxidative capacity. Lipid transfer to HDL was assayed in vitro using a labeled nanoemulsion as the lipid donor. At baseline, the MS group had greater triglyceride levels and a lower HDL cholesterol concentration and lower paraoxonase-1 activity than did the controls. Training decreased the plasma triglycerides but did not change the low-density lipoprotein or HDL cholesterol levels. Nonetheless, exercise training increased the HDL subfractions' antioxidative capacity and paraoxonase-1 activity. After training, the MS group had compositional changes in the smallest HDL subfractions associated with increased free cholesterol and cholesterol ester transfers to HDL, reaching normal values. In conclusion, the present investigation has added relevant information about the dissociation between the quantitative and qualitative aspects of HDL after short-term exercise training without any specific diet in those with the MS, highlighting the importance of evaluating the functional aspects of the lipoproteins, in addition to their plasma levels. Copyright © 2011 Elsevier Inc. All rights reserved.

Hypericum grandifolium Choisy: a species native to Macaronesian Region with antidepressant effect.

PubMed

Sánchez-Mateo, C C; Bonkanka, C X; Rabanal, R M

2009-01-21

Various species of Hypericum genus have been used in the Canary Islands as sedative, diuretic, vermifuge, wound healing, antihysteric and antidepressant agent. Studies have shown that methanol extract of Hypericum grandifolium Choisy is active in tetrabenazine-induced ptosis and forced swimming tests. In the current study, the aqueous, butanol and chloroform fractions obtained from the methanol extract as well as three sub-fractions derived from the chloroform fraction were evaluated for their central nervous effects in mice, particularly their antidepressant activity. The central nervous effect of different fractions and sub-fractions of Hypericum grandifolium was evaluated in mice using various behavioural models including locomotor and muscle relaxant activity, forced swimming test, effect on normal body temperature, barbiturate-induced sleep, tetrabenazine-induced syndrome and 5-hydroxytryptohan-induced head twitches and syndrome. We found that the butanol and chloroform fractions and all sub-fractions showed an antidepressant effect in the forced swimming test, the chloroform fraction being the most active. They produced no effects or only a slight depression of locomotor activity. Chloroform fraction significantly increased the pentobarbital-induced sleeping time, produced a slight but significant hypothermia and antagonized tetrabenazine-induced ptosis, whereas the butanol fraction produced a slight potentiation of 5-HTP-induced head twitches and syndrome. The present results, together with previous pharmacological and phytochemical data, indicated that Hypericum grandifolium possess antidepressant-like effects in mice and that different constituents, such as the flavonoids and the benzophenone derivatives, could be responsible at least in part for the antidepressant effects observed for this species.

First isolation of glutinol and a bioactive fraction with good anti-inflammatory activity from n-hexane fraction of Peltophorum africanum leaf.

PubMed

Adebayo, Salmon A; Shai, Leshweni J; Eloff, Jacobus N

2017-01-01

To investigate the anti-inflammatory activity of different fractions and glutinol (isolated compound), using nitric oxide synthase and cyclooxygenase (COX) inhibition as an indication of anti-inflammatory activity. Anti-inflammatory activity was evaluated using an in vitro assay determining the inhibition of the activity of pro-inflammatory enzyme model. Cyclooxygenases and inducible nitric oxide synthase are crucial enzymes involved in the pathogenesis of many chronic inflammatory conditions. Sub-fraction F3.3 that was derived from n-hexane fraction of PA leaves significantly inhibited (P = 0.01) the catalytic activity of COX-2 (IC 50  = 0.67 μg/mL) better than isolated compound, glutinol (IC 50  = 1.22 μg/mL), compound 2 (CP2) (IC 50  = 1.71 μg/mL) and sub-fraction F3.3.0 (IC 50  = 1.30 μg/mL). A similar trend was observed in investigation of the inhibition of nitric oxide synthesis in RAW 264.7 cells by F3.3, glutinol, CP2 and F3.3.0. Inducible COX-2 and inducible nitric oxide synthase are among potent signalling enzymes that exacerbate inflammation. Bioactive sub-fractions (F3.3 and F3.3.0) derived from the n-hexane fraction of PA had good anti-inflammatory activity, and the isolated compound, and glutinol may be useful as a template for the development of new anti-inflammatory drugs. Copyright © 2017 Hainan Medical University. Production and hosting by Elsevier B.V. All rights reserved.

Cucumis sativus Aqueous Fraction Inhibits Angiotensin II-Induced Inflammation and Oxidative Stress In Vitro

PubMed Central

Trejo-Moreno, Celeste; Méndez-Martínez, Marisol; Perez-Garcia, Maria Dolores; Medina-Campos, Omar N.; Pedraza-Chaverri, José; Santana, María Angélica; Esquivel-Guadarrama, Fernando R.; Castillo, Aida; Cervantes-Torres, Jacquelynne; Fragoso, Gladis; Rosas-Salgado, Gabriela

2018-01-01

Inflammation and oxidative stress play major roles in endothelial dysfunction, and are key factors in the progression of cardiovascular diseases. The aim of this study was to evaluate in vitro the effect of three subfractions (SFs) from the Cucumis sativus aqueous fraction to reduce inflammatory factors and oxidative stress induced by angiotensin II (Ang II) in human microvascular endothelial cells-1 (HMEC-1) cells. The cells were cultured with different concentrations of Ang II and 0.08 or 10 μg/mL of SF1, SF2, or SF3, or 10 μmol of losartan as a control. IL-6 (Interleukin 6) concentration was quantified. To identify the most effective SF combinations, HMEC-1 cells were cultured as described above in the presence of four combinations of SF1 and SF3. Then, the effects of the most effective combination on the expression of adhesion molecules, the production of reactive oxygen species (ROS), and the bioavailability of nitric oxide (NO) were evaluated. Finally, a mass spectrometry analysis was performed. Both SF1 and SF3 subfractions decreased the induction of IL-6 by Ang II, and C4 (SF1 and SF3, 10 μg/mL each) was the most effective combination to inhibit the production of IL-6. Additionally, C4 prevented the expression of adhesion molecules, reduced the production of ROS, and increased the bioavailability of NO. Glycine, arginine, asparagine, lysine, and aspartic acid were the main components of both subfractions. These results demonstrate that C4 has anti-inflammatory and antioxidant effects. PMID:29495578

Precautionary Practices of Healthcare Workers Who Disinfect Medical and Dental Devices Using High-Level Disinfectants

PubMed Central

Henn, Scott A.; Boiano, James M.; Steege, Andrea L.

2016-01-01

Background High-level disinfectants (HLDs) are used throughout the healthcare industry to chemically disinfect reusable, semicritical medical and dental devices to control and prevent healthcare-associated infections among patient populations. Workers who use HLDs are at risk of exposure to these chemicals, some of which are respiratory and skin irritants and sensitizers. Objective To evaluate exposure controls used and to better understand impediments to healthcare workers using personal protective equipment while handling HLDs. Design Web-based survey. Participants A targeted sample of members of professional practice organizations representing nurses, technologists/technicians, dental professionals, respiratory therapists, and others who reported handling HLDs in the previous 7 calendar days. Participating organizations invited either all or a random sample of members via email, which included a hyperlink to the survey. Methods Descriptive analyses were conducted including simple frequencies and prevalences. Results A total of 4,657 respondents completed the survey. The HLDs used most often were glutaraldehyde (59%), peracetic acid (16%), and ortho-phthalaldehyde (15%). Examples of work practices or events that could increase exposure risk included failure to wear water-resistant gowns (44%); absence of standard procedures for minimizing exposure (19%); lack of safe handling training (17%); failure to wear protective gloves (9%); and a spill/leak of HLD during handling (5%). Among all respondents, 12% reported skin contact with HLDs, and 33% of these respondents reported that they did not always wear gloves. Conclusion Findings indicated that precautionary practices were not always used, underscoring the importance of improved employer and worker training and education regarding HLD hazards. PMID:25633000

Variation among Staphylococcus aureus membrane vesicle proteomes affects cytotoxicity of host cells.

PubMed

Jeon, Hyejin; Oh, Man Hwan; Jun, So Hyun; Kim, Seung Il; Choi, Chi Won; Kwon, Hyo Il; Na, Seok Hyeon; Kim, Yoo Jeong; Nicholas, Asiimwe; Selasi, Gati Noble; Lee, Je Chul

2016-04-01

Staphylococcus aureus secretes membrane-derived vesicles (MVs), which can deliver virulence factors to host cells and induce cytopathology. However, the cytopathology of host cells induced by MVs derived from different S. aureus strains has not yet been characterized. In the present study, the cytotoxic activity of MVs from different S. aureus isolates on host cells was compared and the proteomes of S. aureus MVs were analyzed. The MVs purified from S. aureus M060 isolated from a patient with staphylococcal scalded skin syndrome showed higher cytotoxic activity toward host cells than that shown by MVs from three other clinical S. aureus isolates. S. aureus M060 MVs induced HEp-2 cell apoptosis in a dose-dependent manner, but the cytotoxic activity of MVs was completely abolished by treatment with proteinase K. In a proteomic analysis, the MVs from three S. aureus isolates not only carry 25 common proteins, but also carry ≥60 strain-specific proteins. All S. aureus MVs contained δ-hemolysin (Hld), γ-hemolysin, leukocidin D, and exfoliative toxin C, but exfoliative toxin A (ETA) was specifically identified in S. aureus M060 MVs. ETA was delivered to HEp-2 cells via S. aureus MVs. Both rETA and rHld induced cytotoxicity in HEp-2 cells. In conclusion, MVs from clinical S. aureus isolates differ with respect to cytotoxic activity in host cells, and these differences may result from differences in the MV proteomes. Further proteogenomic analysis or mutagenesis of specific genes is necessary to identify cytotoxic factors in S. aureus MVs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mutagenicity of adsorbates to a copper-phthalocyanine derivative recovered from municipal river water.

PubMed

Sayato, Y; Nakamuro, K; Ueno, H; Goto, R

1990-12-01

Blue cotton, bearing a covalently bound copper-phthalocyanine derivative capable of adsorbing polycyclic aromatic hydrocarbons (PAHs) over 3 rings, was applied to recover mutagens from the Katsura River which is a tributary of the Yodo River. The Ames Salmonella/microsome assay with TA98 and TA100 of the blue cotton concentrate recovered from the river water demonstrated indirect mutagenicity toward TA98. The subfractions separated by Sephadex G-25 gel chromatography also showed direct mutagenicity in strains YG1021 and YG1024, the nitroreductase- and O-acetyltransferase-overproducing derivatives of TA98; this activity was greatly increased by the addition of S9 mix, especially in YG1024. However, these subfractions were less mutagenic with TA98NR or TA98/1,8-DNP6, regardless of whether S9 mix was present or not. The behaviors of these mutagenic activities therefore suggested that frameshift mutagens of both directly mutagenic nitroarenes and indirectly mutagenic aminoarenes were present in the blue cotton concentrate from the river water.

Identification of (E,E)-2,4-undecadienal from coriander (Coriandrum sativum L.) as a highly effective deodorant compound against the offensive odor of porcine large intestine.

PubMed

Ikeura, Hiromi; Kohara, Kaori; Li, Xin-Xian; Kobayashi, Fumiyuki; Hayata, Yasuyoshi

2010-10-27

The leaves of coriander ( Coriandrum sativum L.) exhibited a strong deodorizing effect against porcine internal organs (large intestine). The effective deodorizing compounds of coriander were identified by separating the volatile component of coriander, testing the effectiveness of each fraction against the offensive odor of porcine large intestine, and then identifying the compounds by GC-MS. The volatile component of coriander was first separated into six fractions (A-F) by preparative gas chromatography, and the deodorizing activity of each of these fractions against the offensive odor was measured. Fraction D, which showed the strongest deodorizing effect, was then separated into 12 subfractions by preparative GC. The deodorant activity of each subfraction was evaluated, and the deodorant compounds were identified by GC-MS. It was discovered that (E,E)-2,4-undecadienal was the most effective deodorizing compound. The deodorizing activity of (E,E)-2,4-undecadienal on the porcine large intestine increased as with concentration, reaching almost complete deodorizing ability at 10 ppb.

Effect of rising atmospheric carbon dioxide concentration on the protein composition of cereal grain.

PubMed

Wroblewitz, Stefanie; Hüther, Liane; Manderscheid, Remy; Weigel, Hans-Joachim; Wätzig, Hermann; Dänicke, Sven

2014-07-16

The present study investigates effects of rising atmospheric CO2 concentration on protein composition of maize, wheat, and barley grain, especially on the fractions prolamins and glutelins. Cereals were grown at different atmospheric CO2 concentrations to simulate future climate conditions. Influences of two nitrogen fertilization levels were studied for wheat and barley. Enriched CO2 caused an increase of globulin and B-hordein of barley. In maize, the content of globulin, α-zein, and LMW polymers decreased, whereas total glutelin, zein, δ-zein, and HMW polymers rose. Different N supplies resulted in variations of barley subfractions and wheat globulin. Other environmental influences showed effects on the content of nearly all fractions and subfractions. Variations in starch-protein bodies caused by different CO2 treatments could be visualized by scanning electron microscopy. In conclusion, climate change would have impacts on structural composition of proteins and, consequently, on the nutritional value of cereals.

[Inhibition of oxidation of human blood low density lipoproteins by carotenoids from paprika].

PubMed

Medvedeva, N V; Andreenkov, V A; Morozkin, A D; Sergeeva, E A; Prokof'ev, Iu I; Misharin, A Iu

2003-01-01

beta-Carotene (C1), acyl derivatives of capsanthin (C2), and acyl derivatives of capsorubin (C3) were isolated from red paprika (Capsicum annuum) oleoresin. Incorporation of carotenoids C1, C2, and C3 into human plasma LDLs changed the LDL flotation coefficient distribution for LDL fraction 1.019 < d < 1.050 g/ml. The comparative studies of Cu(2+)-catalyzed oxidation for LDL, LDL-C1, LDL-C2, and LDL-C3 revealed that carotenoids C1, C2, and C3 efficiently suppressed the oxidation of LDL, inhibited the formation of conjugated dienes from polyunsaturated fatty acid residues, lowered the content of small dense LDL subfraction, and inhibited the transformation of cholesterol to auto oxidized products (in particular to 5,6-epoxycholesterol, 7-ketocholesterol and 7 beta-hydroxycholesterol). This suggests that the main carotenoids may effectively inhibit LDL oxidation in vitro with probable lowering the "atherogenic" LDL subfraction production in vivo.

Structure Characterization and Immunomodulating Effects of Polysaccharides Isolated from Dendrobium officinale.

PubMed

Wei, Wei; Feng, Lei; Bao, Wan-Rong; Ma, Dik-Lung; Leung, Chung-Hang; Nie, Shao-Ping; Han, Quan-Bin

2016-02-03

A crude polysaccharide fraction (cDOP) has been determined to be the characteristic marker of Dendrobium officinale, an expensive tea material in Asia, but its chemistry and bioactivity have not been studied. In work reported here, cDOP was destarched (DOP, 90% yield) and separated into two subfraction polysaccharides, DOPa and DOPb, which were characterized by monosaccharide composition and methylation analyses and spectral analyses (FT-IR and (1)H and (13)C NMR). Both are composed of mannose and glucose at similar ratios and have a similar structure with a backbone of 1,4-linked β-D-mannopyranosyl and β-D-glucopyranosyl residues. Significant differences were observed only in their molecular weights. Bioassay using mouse macrophage cell line RAW264.7 indicated that DOP and its two subfractions enhance cell proliferation, TNF-α secretion, and phagocytosis in a dose-dependent manner. They also induced the proliferation of lymphocytes alone and with mitogens. DOPa and DOPb are thus proven to be major, active polysaccharide markers of D. officinale.

1,2,4-trihydroxynaphthalene-2-O-β-D-glucopyranoside: A new powerful antioxidant and inhibitor of Aβ42 aggregation isolated from the leaves of Lawsonia inermis.

PubMed

Dhouafli, Zohra; Ben Jannet, Hichem; Mahjoub, Borhane; Leri, Manuela; Guillard, Jérôme; Saidani Tounsi, Moufida; Stefani, Massimo; Hayouni, El Akrem

2017-12-29

Mounting evidence indicates free radicals as toxic species causing damage to human cells leading to the pathogenesis of many diseases such as neurodegenerative disease. Plant derived antioxidants are considered as promising strategy to prevent free radical toxicity. In this study, the crude extract (CE), 50%MeOH, Petroleum Ether (PE) and Ethyl acetate (EA) fractions of Lawsonia inermis leaves were investigated for their antioxidant activity and their ability to counteract amyloid-β 42 (Aβ 42 ) aggregation. Elution of the most bioactive fraction (EA) on silica gel column chromatography led to six sub-fractions. The most active sub-fraction (1) was further resolved on silica gel column chromatography. A new compound with powerful antioxidant and anti-Aβ 42 aggregation properties was purified and characterised by spectroscopic methods as 1,2,4-trihydroxynaphthalene-2-O-β-D-glucopyranoside (THNG). This finding suggests that the antioxidant and anti-Aβ 42 aggregation activities of L. inermis leaves are strongly correlated to this compound.

Extraction, fractionation and re-fractionation of Artemisia nilagirica for anticancer activity and HPLC-ESI-QTOF-MS/MS determination.

PubMed

Sahu, Neha; Meena, Sanjeev; Shukla, Vijaya; Chaturvedi, Priyank; Kumar, Brijesh; Datta, Dipak; Arya, K R

2018-03-01

Medicinal plants used in traditional medicines are affordable, easily accessible, safer, less toxic and considered as a rich or efficient source of bioactive molecules for modern therapeutics. Artemisia nilagirica (AR) has a long history of use in Indian traditional medicine to combat a wide variety of diseases including cancer. Considering the vast potential of traditional healing plants to deliver safer, less toxic and efficient chemotherapeutics, we have examined anticancer activity of ethanolic extract, bioactive fractions and sub-fractions of AR against different human cancer cell lines along with their phytochemical analysis to understand the insights of novel anticancer activities for further preclinical studies. Fresh plant material of AR was procured from the wild, dried and ground. The grinded materials was extracted in ethanol (AR-01) and fractionated into butanol (AR-02), ethyl acetate (AR-03), hexane (AR-04) and water (AR-05). The cytotoxicity was evaluated against three different human cancer cell lines, i.e. colon (DLD-1), lung (A-549), and breast (MCF-7) using Sulforhodamine B (SRB) assay along with non-cancerous VERO cells as control and doxorubicin (DOX) as positive control. As we observed strong cytotoxicity of AR-03 and AR-04 fractions against tested cells and marked cytotoxic effects particularly in colon cancer cell lines, we further re-fractionated, AR-03 into (AR-03A, AR-03B, AR-03C, AR-03D, AR-03E) and AR-04 into (AR-04A, AR-04B, AR-04C) sub-fractions by column chromatography and investigated against the same panel of cell lines in addition to one more colon cancer cell line (HT-29). Phytochemical analysis was performed through HPLC-ESI-QTOF-MS/MS fragmentation. Ethyl acetate (AR-03) and hexane (AR-04) fractions were found to be the most cytotoxic against all the tested cell lines. Further, AR-03E and AR-04A sub-fractions were found more specific cytotoxic selectively against DLD-1 cancer cell lines at 100µg/ml concentration. HPLC

The small dense LDL particle/large buoyant LDL particle ratio is associated with glucose metabolic status in pregnancy.

PubMed

Chen, Yanmin; Du, Mengkai; Xu, Jianyun; Chen, Danqing

2017-12-14

The lipoprotein subfraction particle profile can be used to improve clinical assessments of cardiovascular disease risk and contribute to early detection of atherogenic dyslipidemia. Lipid alterations in gestational diabetes have been extensively studied, but the results have been inconsistent. Here, we investigated serum lipoprotein subfraction particle levels and their association with glucose metabolic status in pregnancy. Twenty-eight pregnant women with gestational diabetes and 56 pregnant women with normal glucose tolerance matched for body mass index were enrolled in this study. We assessed fasting serum lipid concentrations and lipoprotein subfraction particle levels in participants between 24 and 28 weeks of gestation. The level of low-density lipoprotein (LDL) cholesterol was significantly lower in women with gestational diabetes than in those with normal glucose tolerance, but the triglyceride and high-density lipoprotein (HDL) cholesterol levels of the two groups were similar. Lipoprotein particle analysis showed that very-low-density lipoprotein (VLDL) particle number and the small dense LDL particle/large buoyant LDL particle (sdLDL-P/lbLDL-P) ratio were significantly higher in women with gestational diabetes than in those with normal glucose tolerance (P = 0.013 and P = 0.015, respectively). In multivariate analysis, fasting glucose was independently and positively associated with sdLDL-P/lbLDL-P ratio even after adjustment for maternal age, gestational weight gain, BMI and LDL cholesterol (standardized Beta = 0.214, P = 0.029). The sdLDL-P/lbLDL-P ratio is higher in GDM compared with non-diabetic pregnant women, and positively and independently associated with fasting glucose in pregnant women.

Quasi-Langrangian models of nascent thermals

NASA Technical Reports Server (NTRS)

Rambaldi, S.; Randall, D. A.

1981-01-01

The motions in and around an isolated thermal were studied and rising motion in the core, and sinking motion on the outside were found; while the circulation resembled that of a vortex ring. In an entity cloud model, cloudy thermal is tracked, in a Lagrangian fashion, as a discrete entity; the field of motion in and around the thermal is not explicitly simulated. Field of motion cloud models, in which the equations of motion are numerically integrated on an Eulerian grid were developed. It is shown that the great potential of a hybrid cloud model can combine the simplicity of the entity models with the generality and flexibility of the field-of-motion models. A key problem to be overcome in the development of a hybrid model is the formulation of a mathematical framework within which the cloud dynamics can be represented.

Nascent Function Concepts in Nova Scientia

ERIC Educational Resources Information Center

Groetsch, C. W.

2004-01-01

The origin of the function concept is usually traced to Galileo's work on motion. We argue that specific proto-function concepts appeared in the work of Tartaglia a century before the publication of Galileo's Two New Sciences. The study of Tartaglia's ideas can be used in the classroom as a historical introduction to various function concepts,…

Septal membrane localization by C-terminal amphipathic α-helices of MinD in Bacillus subtilis mutant cells lacking MinJ or DivIVA.

PubMed

Ishikawa, Kazuki; Matsuoka, Satoshi; Hara, Hiroshi; Matsumoto, Kouji

2017-10-18

The Min system, which inhibits assembly of the cytokinetic protein FtsZ, is largely responsible for positioning the division site in rod-shaped bacteria. It has been reported that MinJ, which bridges DivIVA and MinD, is targeted to the cell poles by an interaction with DivIVA, and that MinJ in turn recruits MinCD to the cell poles. MinC, however, is located primarily at active division sites at mid-cell when expressed from its native promoter. Surprisingly, we found that Bacillus subtilis MinD is located at nascent septal membranes and at an asymmetric site on lateral membranes between nascent septal membranes in filamentous cells lacking MinJ or DivIVA. Bacillus subtilis MinD has two amphipathic α-helices rich in basic amino acid residues at its C-terminus; one of these, named MTS1 here, is the counterpart of the membrane targeting sequence (MTS) in Escherichia coli MinD while the other, named MTS-like sequence (MTSL), is the nearest helix to MTS1. These amphipathic helices were located independently at nascent septal membranes in cells lacking MinJ or DivIVA, whereas elimination of the helices from the wild type protein reduced its localization considerably. MinD variants with altered MTS1 and MTSL, in which basic amino acid residues were replaced with proline or acidic residues, were not located at nascent septal membranes, indicating that the binding to the nascent septal membranes requires basic residues and a helical structure. The septal localization of MTSL, but not of MTS1, was dependent on host cell MinD. These results suggest that MinD is targeted to nascent septal membranes via its C-terminal amphipathic α-helices in B. subtilis cells lacking MinJ or DivIVA. Moreover, the diffuse distribution of MinD lacking both MTSs suggests that only a small fraction of MinD depends on MinJ for its localization to nascent septal membranes.

21 CFR 866.6030 - AFP-L3% immunological test system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... system is an in vitro device that consists of reagents and an automated instrument used to quantitatively measure, by immunochemical techniques, AFP and AFP-L3 subfraction in human serum. The device is intended for in vitro diagnostic use as an aid in the risk assessment of patients with chronic liver disease...

Multiple-locus variable number of tandem repeats fingerprinting (MLVF) and virulence factor analysis of methicillin resistant Staphylococcus aureus SCCmec type III.

PubMed

Emaneini, Mohammad; Jabalameli, Leila; Iman-Eini, Hossein; Aligholi, Marzieh; Ghasemi, Amir; Nakhjavani, Farrokh Akbari; Taherikalani, Morovat; Khoramian, Babak; Asadollahi, Parisa; Jabalameli, Fereshteh

2011-01-01

Methicillin resistant Staphylococcus aureus (MRSA), particularly strains with type III staphylococcal cassette chromosome mec (SCCmec), represent a serious human pathogen in Tehran, Iran. The disease-causing capability depends on their ability to produce a wide variety of virulent factors. The prevalence of exotoxin genes and multiple-locus variable number of tandem repeats fingerprinting (MLVF) profile among MRSA isolates, from patients in Tehran, was evaluated by PCR and Multiplex-PCR. The MLVF typing of 144 MRSA isolates with type III SCCmec produced 5 different MLVF types. Generally, 97.2% (140/144) of all the isolates were positive for at least one of the tested exotoxin genes. The most prevalent genes were hld, found in 87.5% (126/144) of the isolates followed by lukE-lukD and hla found in 72.9% (105/144) and 70.1% (101/144) of the isolates, respectively. The tst gene, belonging to MLVF types I, IV and V, was found among three of the isolates from blood and wound samples. The sea gene was detected in 58.3% (84/144) of the isolates and the sed and see genes were found in one isolate with MLVF type V. The coexistence of genes was observed in the 87.5% (126/144) of the isolates. The rate of coexistence of hld with lukE-lukD, hla with lukE-lukD and sea with lukE-lukD were 66.7% (96/144), 44.4% (64/144) and 44.4% (64/144), respectively. The present study demonstrated that MRSA strains with type III SCCmec show different MLVF patterns and exotoxin profiles.

Adaptive Change Inferred from Genomic Population Analysis of the ST93 Epidemic Clone of Community-Associated Methicillin-Resistant Staphylococcus aureus

PubMed Central

Stinear, Timothy P.; Holt, Kathryn E.; Chua, Kyra; Stepnell, Justin; Tuck, Kellie L.; Coombs, Geoffrey; Harrison, Paul Francis; Seemann, Torsten; Howden, Benjamin P.

2014-01-01

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has emerged as a major public health problem around the world. In Australia, ST93-IV[2B] is the dominant CA-MRSA clone and displays significantly greater virulence than other S. aureus. Here, we have examined the evolution of ST93 via genomic analysis of 12 MSSA and 44 MRSA ST93 isolates, collected from around Australia over a 17-year period. Comparative analysis revealed a core genome of 2.6 Mb, sharing greater than 99.7% nucleotide identity. The accessory genome was 0.45 Mb and comprised additional mobile DNA elements, harboring resistance to erythromycin, trimethoprim, and tetracycline. Phylogenetic inference revealed a molecular clock and suggested that a single clone of methicillin susceptible, Panton-Valentine leukocidin (PVL) positive, ST93 S. aureus likely spread from North Western Australia in the early 1970s, acquiring methicillin resistance at least twice in the mid 1990s. We also explored associations between genotype and important MRSA phenotypes including oxacillin MIC and production of exotoxins (α-hemolysin [Hla], δ-hemolysin [Hld], PSMα3, and PVL). High-level expression of Hla is a signature feature of ST93 and reduced expression in eight isolates was readily explained by mutations in the agr locus. However, subtle but significant decreases in Hld were also noted over time that coincided with decreasing oxacillin resistance and were independent of agr mutations. The evolution of ST93 S. aureus is thus associated with a reduction in both exotoxin expression and oxacillin MIC, suggesting MRSA ST93 isolates are under pressure for adaptive change. PMID:24482534

The effects of arbuscular mycorrhizal fungi on glomalin-related soil protein distribution, aggregate stability and their relationships with soil properties at different soil depths in lead-zinc contaminated area

PubMed Central

Huang, Li; Ban, Yihui; Tang, Ming

2017-01-01

Glomalin-related soil protein (GRSP), a widespread glycoprotein produced by arbuscular mycorrhizal fungi (AMF), is crucial for ecosystem functioning and ecological restoration. In the present study, an investigation was conducted to comprehensively analyze the effects of heavy metal (HM) contamination on AMF status, soil properties, aggregate distribution and stability, and their correlations at different soil depths (0–10, 10–20, 20–30, 30–40 cm). Our results showed that the mycorrhizal colonization (MC), hyphal length density (HLD), GRSP, soil organic matter (SOM) and soil organic carbon (SOC) were significantly inhibited by Pb compared to Zn at 0–20 cm soil depth, indicating that HM had significant inhibitory effects on AMF growth and soil properties, and that Pb exhibited greater toxicity than Zn at shallow layer of soil. Both the proportion of soil large macroaggregates (>2000 μm) and mean weight diameter (MWD) were positively correlated with GRSP, SOM and SOC at 0–20 cm soil depth (P < 0.05), proving the important contributions of GRSP, SOM and SOC for binding soil particles together into large macroaggregates and improving aggregate stability. Furthermore, MC and HLD had significantly positive correlation with GRSP, SOM and SOC, suggesting that AMF played an essential role in GRSP, SOM and SOC accumulation and subsequently influencing aggregate formation and particle-size distribution in HM polluted soils. Our study highlighted that the introduction of indigenous plant associated with AMF might be a successful biotechnological tool to assist the recovery of HM polluted soils, and that proper management practices should be developed to guarantee maximum benefits from plant-AMF symbiosis during ecological restoration. PMID:28771531

The effects of arbuscular mycorrhizal fungi on glomalin-related soil protein distribution, aggregate stability and their relationships with soil properties at different soil depths in lead-zinc contaminated area.

PubMed

Yang, Yurong; He, Chuangjun; Huang, Li; Ban, Yihui; Tang, Ming

2017-01-01

Glomalin-related soil protein (GRSP), a widespread glycoprotein produced by arbuscular mycorrhizal fungi (AMF), is crucial for ecosystem functioning and ecological restoration. In the present study, an investigation was conducted to comprehensively analyze the effects of heavy metal (HM) contamination on AMF status, soil properties, aggregate distribution and stability, and their correlations at different soil depths (0-10, 10-20, 20-30, 30-40 cm). Our results showed that the mycorrhizal colonization (MC), hyphal length density (HLD), GRSP, soil organic matter (SOM) and soil organic carbon (SOC) were significantly inhibited by Pb compared to Zn at 0-20 cm soil depth, indicating that HM had significant inhibitory effects on AMF growth and soil properties, and that Pb exhibited greater toxicity than Zn at shallow layer of soil. Both the proportion of soil large macroaggregates (>2000 μm) and mean weight diameter (MWD) were positively correlated with GRSP, SOM and SOC at 0-20 cm soil depth (P < 0.05), proving the important contributions of GRSP, SOM and SOC for binding soil particles together into large macroaggregates and improving aggregate stability. Furthermore, MC and HLD had significantly positive correlation with GRSP, SOM and SOC, suggesting that AMF played an essential role in GRSP, SOM and SOC accumulation and subsequently influencing aggregate formation and particle-size distribution in HM polluted soils. Our study highlighted that the introduction of indigenous plant associated with AMF might be a successful biotechnological tool to assist the recovery of HM polluted soils, and that proper management practices should be developed to guarantee maximum benefits from plant-AMF symbiosis during ecological restoration.

Duodenoscope reprocessing surveillance with adenosine triphosphate testing and terminal cultures: a clinical pilot study.

PubMed

Visrodia, Kavel; Hanada, Yuri; Pennington, Kelly M; Tosh, Pritish K; Topazian, Mark D; Petersen, Bret T

2017-07-01

Recent reports of infectious outbreaks linked to duodenoscopes have led to proposals for duodenoscope surveillance culturing, which has inherent limitations. We aimed to assess the feasibility of real-time adenosine triphosphate (ATP) testing after manual cleaning and its ability to predict reprocessing adequacy, as determined by terminal duodenoscope cultures. Clinically used duodenoscopes underwent reprocessing per current guidelines. After manual cleaning, ATP samples were obtained from the elevator, within the proximal biopsy port, and by flushing of the biopsy channel. After high-level disinfection (HLD), aerobic cultures of the elevator and biopsy channel were obtained using sterile technique. Duodenoscopes with any ATP sample ≥200 relative light units underwent repeated cycles of cleaning, ATP testing, HLD, and terminal culturing. Twenty clinically used duodenoscopes were included; 18 underwent a second reprocessing cycle, and 6 underwent a third reprocessing cycle because of detection of high ATP. After the initial reprocessing cycle, 12 of 20 (60%) duodenoscopes had positive culture results, most commonly yielding gram-negative bacilli (GNB, n = 11 from 9 duodenoscopes), and catalase-positive gram-positive cocci (CP-GPC, n = 7 from 7 duodenoscopes), suggesting staphylococcal organisms. Ambient environmental controls also showed GNB and CP-GPC growth. The overall sensitivity and specificity of ATP testing compared with terminal cultures were 30% and 53%, respectively. ATP sampling appears to correlate poorly with terminal culture results and cannot be recommended as a surrogate for terminal cultures. The performance and interpretation of cultures remains complicated by the potential recovery of environmental contaminants. Copyright © 2017 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Using periodic orbits to compute chaotic transport rates between resonance zones.

PubMed

Sattari, Sulimon; Mitchell, Kevin A

2017-11-01

Transport properties of chaotic systems are computable from data extracted from periodic orbits. Given a sufficient number of periodic orbits, the escape rate can be computed using the spectral determinant, a function that incorporates the eigenvalues and periods of periodic orbits. The escape rate computed from periodic orbits converges to the true value as more and more periodic orbits are included. Escape from a given region of phase space can be computed by considering only periodic orbits that lie within the region. An accurate symbolic dynamics along with a corresponding partitioning of phase space is useful for systematically obtaining all periodic orbits up to a given period, to ensure that no important periodic orbits are missing in the computation. Homotopic lobe dynamics (HLD) is an automated technique for computing accurate partitions and symbolic dynamics for maps using the topological forcing of intersections of stable and unstable manifolds of a few periodic anchor orbits. In this study, we apply the HLD technique to compute symbolic dynamics and periodic orbits, which are then used to find escape rates from different regions of phase space for the Hénon map. We focus on computing escape rates in parameter ranges spanning hyperbolic plateaus, which are parameter intervals where the dynamics is hyperbolic and the symbolic dynamics does not change. After the periodic orbits are computed for a single parameter value within a hyperbolic plateau, periodic orbit continuation is used to compute periodic orbits over an interval that spans the hyperbolic plateau. The escape rates computed from a few thousand periodic orbits agree with escape rates computed from Monte Carlo simulations requiring hundreds of billions of orbits.

Selection of antifungal protein-producing molds from dry-cured meat products.

PubMed

Acosta, Raquel; Rodríguez-Martín, Andrea; Martín, Alberto; Núñez, Félix; Asensio, Miguel A

2009-09-30

To control unwanted molds in dry-cured meats it is necessary to allow the fungal development essential for the desired characteristics of the final product. Molds producing antifungal proteins could be useful to prevent hazards due to the growth of mycotoxigenic molds. The objective has been to select Penicillium spp. that produce antifungal proteins against toxigenic molds. To obtain strains adapted to these products, molds were isolated from dry-cured ham. A first screening with 281 isolates by the radial inhibition assay revealed that 166 were active against some of the toxigenic P. echinulatum, P. commune, and Aspergillusniger used as reference molds. The activity of different extracts from cultured medium was evaluated by a microspectroscopic assay. Molds producing active chloroform extracts were eliminated from further consideration. A total of 16 Penicillium isolates were screened for antifungal activity from both cell-free media and the aqueous residues obtained after chloroform extraction. The cell-free media of 10 isolates that produced a strong inhibition of the three reference molds were fractionated by FPLC on a cationic column. For protein purification, the fractions of the three molds that showed high inhibitory activity were further chromatographed on a gel filtration column, and the subfractions containing the highest absorbance peaks were assayed against the most sensitive reference molds. One subfraction each from strains AS51D and RP42C from Penicilliumchrysogenum confirmed the inhibitory activity against the reference molds. SDS-PAGE revealed a single band from each subfraction, with estimated molecular masses of 37kDa for AS51D and 9kDa for RP42C. Although further characterisation is required, both these proteins and the producing strains can be of interest to control unwanted molds on foods.

APOL1 nephropathy risk variants are associated with altered high-density lipoprotein profiles in African Americans.

PubMed

Gutiérrez, Orlando M; Judd, Suzanne E; Irvin, Marguerite R; Zhi, Degui; Limdi, Nita; Palmer, Nicholette D; Rich, Stephen S; Sale, Michèle M; Freedman, Barry I

2016-04-01

Two independent coding variants in the apolipoprotein L1 gene (APOL1), G1 and G2, strongly associate with nephropathy in African Americans; associations with cardiovascular disease are more controversial. Although APOL1 binds plasma high-density lipoproteins (HDLs), data on APOL1 risk variant associations with HDL subfractions are sparse. Two APOL1 G1 single nucleotide polymorphisms and the G2 insertion/deletion polymorphism were genotyped in 2010 Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study participants with nuclear magnetic resonance spectroscopy-based lipoprotein subfraction measurements. Linear regression was used to model associations between numbers of APOL1 G1/G2 risk variants and HDL subfractions, adjusting for demographic, clinical and ancestral covariates. Female sex and higher percentage of African ancestry were positively associated with the number of APOL1 G1/G2 risk alleles. In the unadjusted analysis, mean (standard error) small HDL concentrations (μmol/L) for participants with zero, one and two G1/G2 risk alleles were 19.0 (0.2), 19.7 (0.2) and 19.9 (0.4), respectively (P = 0.02). Adjustment for age, sex, diabetes and African ancestry did not change the results but strengthened the statistical significance (P = 0.004). No significant differences in large or medium HDL, very low-density lipoprotein or low-density lipoprotein particle concentrations were observed by APOL1 genotype. Greater numbers of APOL1 G1/G2 risk alleles were associated with higher small HDL particle concentrations in African Americans. These results may suggest novel areas of investigation to uncover reasons for the association between APOL1 risk variants with adverse outcomes in African Americans. © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

APOL1 nephropathy risk variants are associated with altered high-density lipoprotein profiles in African Americans

PubMed Central

Gutiérrez, Orlando M.; Judd, Suzanne E.; Irvin, Marguerite R.; Zhi, Degui; Limdi, Nita; Palmer, Nicholette D.; Rich, Stephen S.; Sale, Michèle M.; Freedman, Barry I.

2016-01-01

Background Two independent coding variants in the apolipoprotein L1 gene (APOL1), G1 and G2, strongly associate with nephropathy in African Americans; associations with cardiovascular disease are more controversial. Although APOL1 binds plasma high-density lipoproteins (HDLs), data on APOL1 risk variant associations with HDL subfractions are sparse. Methods Two APOL1 G1 single nucleotide polymorphisms and the G2 insertion/deletion polymorphism were genotyped in 2010 Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study participants with nuclear magnetic resonance spectroscopy-based lipoprotein subfraction measurements. Linear regression was used to model associations between numbers of APOL1 G1/G2 risk variants and HDL subfractions, adjusting for demographic, clinical and ancestral covariates. Results Female sex and higher percentage of African ancestry were positively associated with the number of APOL1 G1/G2 risk alleles. In the unadjusted analysis, mean (standard error) small HDL concentrations (μmol/L) for participants with zero, one and two G1/G2 risk alleles were 19.0 (0.2), 19.7 (0.2) and 19.9 (0.4), respectively (P = 0.02). Adjustment for age, sex, diabetes and African ancestry did not change the results but strengthened the statistical significance (P = 0.004). No significant differences in large or medium HDL, very low-density lipoprotein or low-density lipoprotein particle concentrations were observed by APOL1 genotype. Conclusions Greater numbers of APOL1 G1/G2 risk alleles were associated with higher small HDL particle concentrations in African Americans. These results may suggest novel areas of investigation to uncover reasons for the association between APOL1 risk variants with adverse outcomes in African Americans. PMID:26152403

Metabolism of native and naturally occurring multiple modified low density lipoprotein in smooth muscle cells of human aortic intima.

PubMed

Tertov, V V; Orekhov, A N

1997-01-01

The subfraction of low density lipoprotein (LDL) with low sialic acid content that caused accumulation of cholesterol esters in human aortic smooth muscle cells has been found in the blood of coronary atherosclerosis patients. It was demonstrated that this subfraction consists of LDL with small size, high electronegative charge, reduced lipid content, altered tertiary structure of apolipoprotein B, etc. LDL of this subfraction is naturally occurring multiple-modified LDL (nomLDL). In this study we compared the binding, uptake and proteolytic degradation of native LDL and nomLDL by smooth muscle cells cultured from human grossly normal intima, fatty streaks, and atherosclerotic plaques. Uptake of nomLDL by normal and atherosclerotic cells was 3.5- and 6-fold, respectively, higher than uptake of native LDL. Increased uptake of nomLDL was due to increased binding of this LDL by intimal smooth muscle cells. The enhanced binding is explained by the interaction of nomLDL with cellular receptors other than LDL-receptor. Modified LDL interacted with the scavenger receptor, asialoglycoprotein receptor, and also with cell surface proteoglycans. Rates of degradation of nomLDL were 1.5- and 5-fold lower than degradation of native LDL by normal and atherosclerotic cells, respectively. A low rate of nomLDL degradation was also demonstrated in homogenates of intimal cells. Activities of lysosomal proteinases of atherosclerotic cells were decreased compared with normal cells. Pepstatin A, a cathepsin D inhibitor, completely inhibited lipoprotein degradation, while serine, thiol, or metallo-proteinase inhibitors had partial effect. This fact reveals that cathepsin D is involved in initial stages of apoB degradation by intimal smooth muscle cells. Obtained data show that increased uptake and decreased lysosomal degradation of nomLDL may be the main cause of LDL accumulation in human aortic smooth muscle cells, leading to foam cell formation.

Application of NIRS coupled with PLS regression as a rapid, non-destructive alternative method for quantification of KBA in Boswellia sacra

NASA Astrophysics Data System (ADS)

Al-Harrasi, Ahmed; Rehman, Najeeb Ur; Mabood, Fazal; Albroumi, Muhammaed; Ali, Liaqat; Hussain, Javid; Hussain, Hidayat; Csuk, René; Khan, Abdul Latif; Alam, Tanveer; Alameri, Saif

2017-09-01

In the present study, for the first time, NIR spectroscopy coupled with PLS regression as a rapid and alternative method was developed to quantify the amount of Keto-β-Boswellic Acid (KBA) in different plant parts of Boswellia sacra and the resin exudates of the trunk. NIR spectroscopy was used for the measurement of KBA standards and B. sacra samples in absorption mode in the wavelength range from 700-2500 nm. PLS regression model was built from the obtained spectral data using 70% of KBA standards (training set) in the range from 0.1 ppm to 100 ppm. The PLS regression model obtained was having R-square value of 98% with 0.99 corelationship value and having good prediction with RMSEP value 3.2 and correlation of 0.99. It was then used to quantify the amount of KBA in the samples of B. sacra. The results indicated that the MeOH extract of resin has the highest concentration of KBA (0.6%) followed by essential oil (0.1%). However, no KBA was found in the aqueous extract. The MeOH extract of the resin was subjected to column chromatography to get various sub-fractions at different polarity of organic solvents. The sub-fraction at 4% MeOH/CHCl3 (4.1% of KBA) was found to contain the highest percentage of KBA followed by another sub-fraction at 2% MeOH/CHCl3 (2.2% of KBA). The present results also indicated that KBA is only present in the gum-resin of the trunk and not in all parts of the plant. These results were further confirmed through HPLC analysis and therefore it is concluded that NIRS coupled with PLS regression is a rapid and alternate method for quantification of KBA in Boswellia sacra. It is non-destructive, rapid, sensitive and uses simple methods of sample preparation.

Structural basis for translational surveillance by the large ribosomal subunit-associated protein quality control complex

PubMed Central

Lyumkis, Dmitry; Oliveira dos Passos, Dario; Tahara, Erich B.; Webb, Kristofor; Bennett, Eric J.; Vinterbo, Staal; Potter, Clinton S.; Carragher, Bridget; Joazeiro, Claudio A. P.

2014-01-01

All organisms have evolved mechanisms to manage the stalling of ribosomes upon translation of aberrant mRNA. In eukaryotes, the large ribosomal subunit-associated quality control complex (RQC), composed of the listerin/Ltn1 E3 ubiquitin ligase and cofactors, mediates the ubiquitylation and extraction of ribosome-stalled nascent polypeptide chains for proteasomal degradation. How RQC recognizes stalled ribosomes and performs its functions has not been understood. Using single-particle cryoelectron microscopy, we have determined the structure of the RQC complex bound to stalled 60S ribosomal subunits. The structure establishes how Ltn1 associates with the large ribosomal subunit and properly positions its E3-catalytic RING domain to mediate nascent chain ubiquitylation. The structure also reveals that a distinguishing feature of stalled 60S particles is an exposed, nascent chain-conjugated tRNA, and that the Tae2 subunit of RQC, which facilitates Ltn1 binding, is responsible for selective recognition of stalled 60S subunits. RQC components are engaged in interactions across a large span of the 60S subunit surface, connecting the tRNA in the peptidyl transferase center to the distally located nascent chain tunnel exit. This work provides insights into a mechanism linking translation and protein degradation that targets defective proteins immediately after synthesis, while ignoring nascent chains in normally translating ribosomes. PMID:25349383

Analysis of the multiple forms of Gaucher spleen sphingolipid activator protein 2.

PubMed Central

Paton, B C; Poulos, A

1988-01-01

Gaucher spleen sphingolipid activator protein 2 was fractionated into concanavalin A binding- and non-binding fractions. These fractions each contained several bands on non-denaturing polyacrylamide gel electrophoresis (PAGE). The two fractions were further fractionated by electroblotting the proteins from preparative gels onto nitrocellulose, staining with Ponceau S to locate the bands of protein and then eluting the protein components from the nitrocellulose. A total of ten fractions, each containing only one or two major components, was collected. All of these subfractions activated beta-glucocerebrosidase and sphingomyelinase and most subfractions also activated beta-galactocerebrosidase. The structural relationship of the bands was investigated using endoglycosidase digestions. The results indicated that the two bands with the fastest mobility on non-denaturing PAGE did not contain any carbohydrate. The remaining bands showed only limited or partial digestion with endoglycosidase H and endoglycosidase D, but were readily hydrolysed with endoglycosidase F. The products of these digestions included bands with similar mobilities to the non-carbohydrate containing bands. Images Fig. 1. Fig. 2. Fig. 3. PMID:3178760

Functional heterogeneity of side population cells in skeletal muscle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uezumi, Akiyoshi; Ojima, Koichi; Fukada, So-ichiro

2006-03-17

Skeletal muscle regeneration has been exclusively attributed to myogenic precursors, satellite cells. A stem cell-rich fraction referred to as side population (SP) cells also resides in skeletal muscle, but its roles in muscle regeneration remain unclear. We found that muscle SP cells could be subdivided into three sub-fractions using CD31 and CD45 markers. The majority of SP cells in normal non-regenerating muscle expressed CD31 and had endothelial characteristics. However, CD31{sup -}CD45{sup -} SP cells, which are a minor subpopulation in normal muscle, actively proliferated upon muscle injury and expressed not only several regulatory genes for muscle regeneration but also somemore » mesenchymal lineage markers. CD31{sup -}CD45{sup -} SP cells showed the greatest myogenic potential among three SP sub-fractions, but indeed revealed mesenchymal potentials in vitro. These SP cells preferentially differentiated into myofibers after intramuscular transplantation in vivo. Our results revealed the heterogeneity of muscle SP cells and suggest that CD31{sup -}CD45{sup -} SP cells participate in muscle regeneration.« less

Extracts, Anthocyanins and Procyanidins from Aronia melanocarpa as Radical Scavengers and Enzyme Inhibitors

PubMed Central

Bräunlich, Marie; Slimestad, Rune; Wangensteen, Helle; Brede, Cato; Malterud, Karl E.; Barsett, Hilde

2013-01-01

Extracts, subfractions, isolated anthocyanins and isolated procyanidins B2, B5 and C1 from the berries and bark of Aronia melanocarpa were investigated for their antioxidant and enzyme inhibitory activities. Four different bioassays were used, namely scavenging of the diphenylpicrylhydrazyl (DPPH) radical, inhibition of 15-lipoxygenase (15-LO), inhibition of xanthine oxidase (XO) and inhibition of α-glucosidase. Among the anthocyanins, cyanidin 3-arabinoside possessed the strongest and cyanidin 3-xyloside the weakest radical scavenging and enzyme inhibitory activity. These effects seem to be influenced by the sugar units linked to the anthocyanidin. Subfractions enriched in procyanidins were found to be potent α-glucosidase inhibitors; they possessed high radical scavenging properties, strong inhibitory activity towards 15-LO and moderate inhibitory activity towards XO. Trimeric procyanidin C1 showed higher activity in the biological assays compared to the dimeric procyanidins B2 and B5. This study suggests that different polyphenolic compounds of A. melanocarpa can have beneficial effects in reducing blood glucose levels due to inhibition of α-glucosidase and may have a potential to alleviate oxidative stress. PMID:23459328

Extracts, anthocyanins and procyanidins from Aronia melanocarpa as radical scavengers and enzyme inhibitors.

PubMed

Bräunlich, Marie; Slimestad, Rune; Wangensteen, Helle; Brede, Cato; Malterud, Karl E; Barsett, Hilde

2013-03-04

Extracts, subfractions, isolated anthocyanins and isolated procyanidins B2, B5 and C1 from the berries and bark of Aronia melanocarpa were investigated for their antioxidant and enzyme inhibitory activities. Four different bioassays were used, namely scavenging of the diphenylpicrylhydrazyl (DPPH) radical, inhibition of 15-lipoxygenase (15-LO), inhibition of xanthine oxidase (XO) and inhibition of α-glucosidase. Among the anthocyanins, cyanidin 3-arabinoside possessed the strongest and cyanidin 3-xyloside the weakest radical scavenging and enzyme inhibitory activity. These effects seem to be influenced by the sugar units linked to the anthocyanidin. Subfractions enriched in procyanidins were found to be potent α-glucosidase inhibitors; they possessed high radical scavenging properties, strong inhibitory activity towards 15-LO and moderate inhibitory activity towards XO. Trimeric procyanidin C1 showed higher activity in the biological assays compared to the dimeric procyanidins B2 and B5. This study suggests that different polyphenolic compounds of A. melanocarpa can have beneficial effects in reducing blood glucose levels due to inhibition of α-glucosidase and may have a potential to alleviate oxidative stress.

Role of DNA polymerase I-associated 5'-exonuclease in replication of coliphage M13 replicative-form DNA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dasgupta, S.; Mitra, S.

The conversion of both parental- and progeny-nascent open circular M13 RF DNA into covalently closed RF I is drastically reduced in an E. coli mutant deficient in the 5' ..-->.. 3' exonuclease associated with DNA polymerase I. The nascent progeny RF DNA also contains a significant proportion of fragments of smaller than unit length.

Ab initio prediction of fast non-equilibrium transport of nascent polarons in SrI 2: a key to high-performance scintillation [First-principles study of hole polaron formation and migration in strontium iodide

DOE PAGES

Zhou, Fei; Sadigh, Babak; Aberg, Daniel; ...

2016-08-12

The excellent light yield proportionality of europium-doped strontium iodide (SrI 2:Eu) has resulted in state-of-the-art γ-ray detectors with remarkably high-energy resolution, far exceeding that of most halide compounds. In this class of materials, the formation of self-trapped hole polarons is very common. However, polaron formation is usually expected to limit carrier mobilities and has been associated with poor scintillator light-yield proportionality and resolution. Here using a recently developed first-principles method, we perform an unprecedented study of polaron transport in SrI 2, both for equilibrium polarons, as well as nascent polarons immediately following a self-trapping event. We propose a rationale formore » the unexpected high-energy resolution of SrI 2. We identify nine stable hole polaron configurations, which consist of dimerised iodine pairs with polaron-binding energies of up to 0.5 eV. They are connected by a complex potential energy landscape that comprises 66 unique nearest-neighbour migration paths. Ab initio molecular dynamics simulations reveal that a large fraction of polarons is born into configurations that migrate practically barrier free at room temperature. Consequently, carriers created during γ-irradiation can quickly diffuse away reducing the chance for nonlinear recombination, the primary culprit for non-proportionality and resolution reduction. We conclude that the flat, albeit complex, landscape for polaron migration in SrI 2 is a key for understanding its outstanding performance. This insight provides important guidance not only for the future development of high-performance scintillators but also of other materials, for which large polaron mobilities are crucial such as batteries and solid-state ionic conductors.« less

Origins of the Mechanochemical Coupling of Peptide Bond Formation to Protein Synthesis.

PubMed

Fritch, Benjamin; Kosolapov, Andrey; Hudson, Phillip; Nissley, Daniel A; Woodcock, H Lee; Deutsch, Carol; O'Brien, Edward P

2018-04-18

Mechanical forces acting on the ribosome can alter the speed of protein synthesis, indicating that mechanochemistry can contribute to translation control of gene expression. The naturally occurring sources of these mechanical forces, the mechanism by which they are transmitted 10 nm to the ribosome's catalytic core, and how they influence peptide bond formation rates are largely unknown. Here, we identify a new source of mechanical force acting on the ribosome by using in situ experimental measurements of changes in nascent-chain extension in the exit tunnel in conjunction with all-atom and coarse-grained computer simulations. We demonstrate that when the number of residues composing a nascent chain increases, its unstructured segments outside the ribosome exit tunnel generate piconewtons of force that are fully transmitted to the ribosome's P-site. The route of force transmission is shown to be through the nascent polypetide's backbone, not through the wall of the ribosome's exit tunnel. Utilizing quantum mechanical calculations we find that a consequence of such a pulling force is to decrease the transition state free energy barrier to peptide bond formation, indicating that the elongation of a nascent chain can accelerate translation. Since nascent protein segments can start out as largely unfolded structural ensembles, these results suggest a pulling force is present during protein synthesis that can modulate translation speed. The mechanism of force transmission we have identified and its consequences for peptide bond formation should be relevant regardless of the source of the pulling force.

Biochemical Characterization of a Haloalkane Dehalogenase DadB from Alcanivorax dieselolei B-5

PubMed Central

Li, Anzhang; Shao, Zongze

2014-01-01

Recently, we found that Alcanivorax bacteria from various marine environments were capable of degrading halogenated alkanes. Genome sequencing of A. dieselolei B-5 revealed two putative haloalkane dehalogenase (HLD) genes, which were supposed to be involved in degradation of halogenated compounds. In this report, we confirm for the first time that the Alcanivorax bacterium encodes a truly functional HLD named DadB. An activity assay with 46 halogenated substrates indicated that DadB possesses broad substrate range and has the highest overall activity among the identified HLDs. DadB prefers brominated substrates; chlorinated alkenes; and the C2-C3 substrates, including the persistent pollutants of 1,2-dichloroethane, 1,2-dichloropropane and 1,2,3-trichloropropane. As DadB displays no detectable activity toward long-chain haloalkanes such as 1-chlorohexadecane and 1-chlorooctadecane, the degradation of them in A. dieselolei B-5 might be attributed to other enzymes. Kinetic constants were determined with 6 substrates. DadB has highest affinity and largest k cat/K m value toward 1,3-dibromopropane (K m = 0.82 mM, k cat/K m = 16.43 mM−1·s−1). DadB aggregates fast in the buffers with pH≤7.0, while keeps stable in monomer form when pH≥7.5. According to homology modeling, DadB has an open active cavity with a large access tunnel, which is supposed important for larger molecules as opposed to C2-C3 substrates. Combined with the results for other HLDs, we deduce that residue I247 plays an important role in substrate selection. These results suggest that DadB and its host, A. dieselolei B-5, are of potential use for biocatalysis and bioremediation applications. PMID:24586552

A retrospective cohort study of cause-specific mortality and incidence of hematopoietic malignancies in Chinese benzene-exposed workers.

PubMed

Linet, Martha S; Yin, Song-Nian; Gilbert, Ethel S; Dores, Graça M; Hayes, Richard B; Vermeulen, Roel; Tian, Hao-Yuan; Lan, Qing; Portengen, Lutzen; Ji, Bu-Tian; Li, Gui-Lan; Rothman, Nathaniel

2015-11-01

Benzene exposure has been causally linked with acute myeloid leukemia (AML), but inconsistently associated with other hematopoietic, lymphoproliferative and related disorders (HLD) or solid tumors in humans. Many neoplasms have been described in experimental animals exposed to benzene. We used Poisson regression to estimate adjusted relative risks (RR) and the likelihood ratio statistic to derive confidence intervals for cause-specific mortality and HLD incidence in 73,789 benzene-exposed compared with 34,504 unexposed workers in a retrospective cohort study in 12 cities in China. Follow-up and outcome assessment was based on factory, medical and other records. Benzene-exposed workers experienced increased risks for all-cause mortality (RR = 1.1, 95% CI = 1.1, 1.2) due to excesses of all neoplasms (RR = 1.3, 95% CI = 1.2, 1.4), respiratory diseases (RR = 1.7, 95% CI = 1.2, 2.3) and diseases of blood forming organs (RR = ∞, 95% CI = 3.4, ∞). Lung cancer mortality was significantly elevated (RR = 1.5, 95% CI = 1.2, 1.9) with similar RRs for males and females, based on three-fold more cases than in our previous follow-up. Significantly elevated incidence of all myeloid disorders reflected excesses of myelodysplastic syndrome/acute myeloid leukemia (RR = 2.7, 95% CI = 1.2, 6.6) and chronic myeloid leukemia (RR = 2.5, 95% CI = 0.8, 11), and increases of all lymphoid disorders included excesses of non-Hodgkin lymphoma (RR = 3.9, 95%CI = 1.5, 13) and all lymphoid leukemia (RR = 5.4, 95%CI = 1.0, 99). The 28-year follow-up of Chinese benzene-exposed workers demonstrated increased risks of a broad range of myeloid and lymphoid neoplasms, lung cancer, and respiratory diseases and suggested possible associations with other malignant and non-malignant disorders. © 2015 UICC.

Identification and Characterization of Staphylococcus aureus Strains with an Incomplete Hemolytic Phenotype.

PubMed

Zhang, Haifang; Zheng, Yi; Gao, Huasheng; Xu, Ping; Wang, Min; Li, Aiqing; Miao, Minhui; Xie, Xiaofang; Deng, Yimai; Zhou, Huiqin; Du, Hong

2016-01-01

Staphylococcus aureus is a common pathogen causing both hospital and community-acquired infections. Hemolysin is one of the important virulence factors for S. aureus and causes the typical β-hemolytic phenotype which is called complete hemolytic phenotype as well. Recently, S. aureus with an incomplete hemolytic phenotype (SIHP) was isolated from clinical samples. To study the microbiologic characteristics of SIHP, the special hemolytic phenotype of SIHP was verified on the sheep blood agar plates supplied by different manufacturers. Expression of hemolysin genes hla, hlb, hlgC , and hld of SIHP was detected by qRT-PCR and it was showed that expression of hlb in SIHP was obviously increased compared to the control S. aureus strains with complete hemolytic phenotype (SCHP), while the expression of hla, hlgC , and hld in SIHP was significantly decreased. In addition, the α-hemolysin encoded by gene hla was decreased obviously in SIHP compared to SCHP by western blot. All 60 SIHP strains were identified to be the methicillin resistant S. aureus (MRSA), and moreover these SIHP strains all contains mecA gene. The virulence gene tst were all present in SIHP, and the intracellular survival ability of SIHP was much greater than that of the gene tst negative S. aureus . We also found that IL-2, IL-6, and IL-17A secreted in the supernatant of SIHP infected macrophages increased significantly compared to tst negative control strains infected ones. MLST analysis showed that all of SIHP strains were classified into ST5 clone. To our knowledge, this study firstly showed that SIHP strains are a kind of methicillin resistant strains which express β-hemolysin highly and possess a potential high virulence, and it was suggested that SIHP should be paid more attention in hospital.

Macrophage Biochemistry, Activation and Function

DTIC Science & Technology

1981-01-01

vacuolar apparatus become more abundant. Functional capabilities, including phagocytic activity, protein synthesis and surface receptors, also increase...properties of cell components of other tissues has led to the following assignment of marker enzymes to specific macrophage components. This assessment is...subfractions. The surface area of each histogram bar then gives the frac- tional amount of constituent present within each normalized fraction. Distribution

Petrogenesis of meta-volcanic rocks from the Maimón Formation (Dominican Republic): Geochemical record of the nascent Greater Antilles paleo-arc

NASA Astrophysics Data System (ADS)

Torró, Lisard; Proenza, Joaquín A.; Marchesi, Claudio; Garcia-Casco, Antonio; Lewis, John F.

2017-05-01

stages transitional between FAB and first-island arc magmatism, whereas Group 2 boninitic lavas resulted from focused flux melting and higher degrees of melt extraction in a more mature stage of subduction. Group 3 basalts probably represent magmatism taking place immediately before the establishment of a steady-state subduction regime. The relatively high extents of flux melting and slab input recorded in the Maimón lavas support a scenario of hot subduction beneath the nascent Greater Antilles paleo-arc. Paleotectonic reconstructions and the markedly depleted, though heterogeneous character of the mantle source, indicate the rise of shallow asthenosphere which had sourced mid-ocean ridge basalts (MORB) and/or back-arc basin basalts (BABB) in the proto-Caribbean domain prior to the inception of SW-dipping subduction. Relative to the neighbouring Aptian-Albian Los Ranchos Formation, we suggest that Maimón volcanic rocks extruded more proximal to the vertical projection of the subducting proto-Caribbean spreading ridge.

The spin evolution of nascent neutron stars

NASA Astrophysics Data System (ADS)

Watts, Anna L.; Andersson, Nils

2002-07-01

The loss of angular momentum owing to unstable r-modes in hot young neutron stars has been proposed as a mechanism for achieving the spin rates inferred for young pulsars. One factor that could have a significant effect on the action of the r-mode instability is fallback of supernova remnant material. The associated accretion torque could potentially counteract any gravitational-wave-induced spin-down, and accretion heating could affect the viscous damping rates and hence the instability. We discuss the effects of various external agents on the r-mode instability scenario within a simple model of supernova fallback on to a hot young magnetized neutron star. We find that the outcome depends strongly on the strength of the magnetic field of the star. Our model is capable of generating spin rates for young neutron stars that accord well with initial spin rates inferred from pulsar observations. The combined action of r-mode instability and fallback appears to cause the spin rates of neutron stars born with very different spin rates to converge, on a time-scale of approximately 1 year. The results suggest that stars with magnetic fields <=1013G could emit a detectable gravitational wave signal for perhaps several years after the supernova event. Stars with higher fields (magnetars) are unlikely to emit a detectable gravitational wave signal via the r-mode instability. The model also suggests that the r-mode instability could be extremely effective in preventing young neutron stars from going dynamically unstable to the bar-mode.

Antiamoebic Activity of Petiveria alliacea Leaves and Their Main Component, Isoarborinol.

PubMed

Zavala Ocampo, Lizeth M; Aguirre-HernÁndez, Eva; Pérez-HernÁndez, Nury; Rivera, Gildardo; Marchat, Laurence A; Ramírez-Moreno, Esther

2017-08-28

Petiveria alliacea L. (Phytolacaceae) is a medicinal plant with a broad range of traditional therapeutic properties, including the treatment of dysentery and intestinal infections caused by protozoan parasites. However, its effects against Entamoeba histolytica have not been reported yet. We investigated the antiamoebic activity present in the leaves of P. alliacea Antiamoebic activity was evaluated in methanolic and aqueous extracts, as well as in the hexanic, methanolic, and EtOAc fractions. The P. alliacea methanolic extract showed a better antiamoebic activity than the aqueous extract with an IC 50 = 0.51 mg/ml. Likewise, the hexanic fraction was the most effective fraction, showing a dose-dependent activity against E. histolytica , with an IC 50 = 0.68 mg/ml. Hexanic subfraction 12-19 showed the highest antiamoebic activity at 0.8 mg/ml, producing 74.3% growth inhibition without any toxicity in mammal cells. A major component in subfraction 12-19 was identified as isoarborinol, which produced 51.4% E. histolytica growth inhibition at 0.05 mg/ml without affecting mammal cells. The P. alliacea leaf extract has antiamoebic activity that can be attributed to a major metabolite known as isoarborinol.

[Anti-fungi activity of organic extracts from the tree Fagara monophylla (Rutaceae) in Venezuela].

PubMed

Gómez, Yrma; Gil, Katiuska; González, Elba; Farías, Luz Marina

2007-01-01

The tree Fagara monophylla ranges throughout Tropical America. The genus Fagara has a diversity of alkaloid compounds with antibiotic properties; nevertheless, there are few reports antifungal activity of its organic compounds. Organic extracts from Venezuelan F. monophylla were tested for antimicrobial activity against Aspergillus terreus, A. flavus, Penicillium digitatum, P. funiculosum, P. citrinum, Paecilomyces and Candida albicans. Minimal Inhibitory Concentration (MIC) was determined. The susceptibility trials of organic fractions (Hex., CH2Cl2 and MeOH) showed that the highest inhibition was presented by MeOH against A. flavus (55 mm), P. digitatum (60 mm), P. funiculosum (56 mm) and C. albicans (26 mm). The activities of MeOH/EtOAc fractions 1 and 2 suggest a combined effect against A. flavus, P. digitatum and P. funiculosum. The MIC of 1 MeOH/ EtOAc subfraction activity was lower against C. albicans (32 microg/ml) and moderate (128 microg/ml) against P. digitatum. This organic extract has a great antifungal potential. The phytochemical proves and TLC testing on the organic extract, and the MeOH/EtOAc subfraction, respectively, indicated the presence of alkaloid compounds.

The Battle of RNA Synthesis: Virus versus Host.

PubMed

Harwig, Alex; Landick, Robert; Berkhout, Ben

2017-10-21

Transcription control is the foundation of gene regulation. Whereas a cell is fully equipped for this task, viruses often depend on the host to supply tools for their transcription program. Over the course of evolution and adaptation, viruses have found diverse ways to optimally exploit cellular host processes such as transcription to their own benefit. Just as cells are increasingly understood to employ nascent RNAs in transcription regulation, recent discoveries are revealing how viruses use nascent RNAs to benefit their own gene expression. In this review, we first outline the two different transcription programs used by viruses, i.e., transcription (DNA-dependent) and RNA-dependent RNA synthesis. Subsequently, we use the distinct stages (initiation, elongation, termination) to describe the latest insights into nascent RNA-mediated regulation in the context of each relevant stage.

Oligosaccharyltransferase directly binds to ribosome at a location near the translocon-binding site

PubMed Central

Harada, Yoichiro; Li, Hua; Li, Huilin; Lennarz, William J.

2009-01-01

Oligosaccharyltransferase (OT) transfers high mannose-type glycans to the nascent polypeptides that are translated by the membrane-bound ribosome and translocated into the lumen of the endoplasmic reticulum through the Sec61 translocon complex. In this article, we show that purified ribosomes and OT can form a binary complex with a stoichiometry of ≈1 to 1 in the presence of detergent. We present evidence that OT may bind to the large ribosomal subunit near the site where nascent polypeptides exit. We further show that OT and the Sec61 complex can simultaneously bind to ribosomes in vitro. Based on existing data and our findings, we propose that cotranslational translocation and N-glycosylation of nascent polypeptides are mediated by a ternary supramolecular complex consisting of OT, the Sec61 complex, and ribosomes. PMID:19365066

Effect of long term organic amendments and vegetation of vineyard soils on the microscale distribution and biogeochemistry of copper.

PubMed

Navel, Aline; Martins, Jean M F

2014-01-01

In this study we evaluated the effect of the long term organic management of a vineyard-soil on the biogeochemistry of copper at the micro-aggregate scale. The model vineyard-soil (Mâcon-France) experienced a long-term field-experiment that consisted in amendments and vegetations with various materials and plants. We studied specifically the effect of Straw (S) and Conifer Compost (CC) organic amendments and Clover (Cl) and Fescue (F) vegetation on the fate of copper (fungicide) in the surface layer of this loamy soil, through a comparison with the Non Amended soil (NA). After collection the five soils were immediately physically fractionated in order to obtain 5 granulometric size-fractions. All soils and size-fractions were quantitatively characterized in terms of granulometry, chemical content and copper distribution, speciation and bioavailability to bacteria and plants. The results showed strong increases of soil-constituents aggregation for all treatments (Cl>CC>S>F>NA), in relation with the increased cementation of soil-constituents by organic matter (OM). The distribution patterns of all major elements and organic carbon were found highly variable within the soil sub-fractions and also between the 5 treatments. Due to their specific inorganic and organic composition, soil sub-fractions can thus be considered as a specific microbial habitat. Added OM accumulated preferentially in the 20-2 μm and in the >250 μm of the 5 soils. The distribution patterns of copper as well as its speciation and bioavailability to bacteria in the soil sub-fractions were shown to be strongly different among the five soils, in relation with OM distribution. Our results also suggest that Cu-bioavailability to plants is controlled by soil-rhizosphere structure. Altogether our results permitted to show that long-term organic management of a vineyard soil induced stable modifications of soil physical and chemical properties at both macro and micro-scales. These modifications

Extraction of saponins and toxicological profile of Teucrium stocksianum boiss extracts collected from District Swat, Pakistan.

PubMed

Shah, Syed Muhammad Mukarram; Sadiq, Abdul; Shah, Syed Muhammad Hassan; Khan, Shahzeb

2014-12-04

The current era is facing challenges in the management of neoplasia and weeds control. The currently available anti-cancer and herbicidal drugs are associated with some serious side effects. Therefore numerous researchers are trying to discover and develop plant based alternative particularly for the rational management of cancer and weed control. Teucrium stocksianum possess antioxidant and analgesic activities. The current study was designed to evaluate crude saponins (CS), methanolic extract and sub-fractions of T. stocksianum for cytotoxic and phytotoxic potentials. CS, methanolic extract and sub-fractions were extracted from powdered plant material using different solvents. Cytotoxic potential of the extracts at a dose of 10, 100 and 1000 μg/ml were evaluated against Brine shrimp's nauplii. Phytotoxic assay also performed at the same concentration against Lemna minor. Etoposide and Paraquat were used as positive controls in cytotoxic and phytotoxic assays respectively. The percent yield of crude saponins was (5%). CS demonstrated tremendous brine shrimp lethality showing < 10 μg/ml LC50. The n-hexane (HF) and chloroform fractions (CF) demonstrated excellent cytotoxicity with 80 and 55 μg/ml LC50 respectively. Whereas the methanolic extract (TSME), ethyl acetate (EAF) and aqueous fractions (AF) revealed moderate cytotoxicity showing 620, 860 and 1000 μg/ml LC50 values respectively. In phytotoxic assay profound inhibition was displayed by HF (96.67%) and TSME (95.56%, 30 μg/ml LC50) against the growth of Lemna minor at 1000 μg/ml respectively. Both CF and EAF demonstrated profound phytoxicity (93.33%) respectively at highest concentration (1000 μg/ml), while AF and CS demonstrated weak phytotoxicity with 1350 and 710 μg/ml LC50 values respectively. Cytotoxicity and phytotoxicity assays indicated that the crude saponins, n-hexane and chloroform fractions of T. stocksianum could play a vital role in the treatment of neoplasia and as potential natural

Antimycobacterial potency and cytotoxicity study of three medicinal plants.

PubMed

Tsouh Fokou, Patrick Valere; Appiah-Opong, Regina; Yeboah-Manu, Dorothy; Kissi-Twum, Abena Adomah; Yamthe, Lauve Rachel Tchokouaha; Mokale Kognou, Aristide Laurel; Addo, Phyllis; Boyom, Fabrice Fekam; Nyarko, Alexander Kwadwo

2016-12-01

Mycobacterial infections including tuberculosis, leprosy, and buruli ulcer are among the most prevalent, debilitating, and deadly tropical diseases, especially in Sub-Saharan Africa. The development of drug resistance to the currently available drugs and the poor compliance emphasize the need for new chemotherapeutic agents. This study was designed to evaluate the in vitro activity of Cleistopholis patens, Annona reticulata, and Greenwayodendron suaveolens against Mycobacterium smegmatis. The safety on normal liver cells was also assessed. The crude extracts, fractions, and subfractions were tested against M. smegmatis and for cell cytotoxicity on WRL-68, normal human hepatocyte using microdilution resazurin-based assays. The phytochemical screening was performed using standard methods. Most of the extracts, fractions, and subfractions inhibited the growth of M. smegmatis with minimum inhibitory concentration (MIC) values ranging from 6.25μg/mL to 125μg/mL. The subfractions P12 and P29 from G. suaveolens twig were more potent with MIC values of 6.25μg/mL and 25μg/mL, respectively. Fruit crude extract and root CH 2 Cl 2 fraction from A. reticulata also showed activity with MIC values of 50μg/mL and 25μg/mL, respectively. Crude extracts from the twig and stem bark of C. patens displayed inhibition at MIC values of 125μg/mL and 100μg/mL, respectively. Majority of active extracts showed no cell cytotoxicity, except the extract from C. patens with IC 50 ranging from 41.40μg/mL to 93.78μg/mL. The chemical investigation of the promising extracts revealed the presence of phenols, alkaloids, glycosides, triterpenes, and acetogenins. The results achieved from this preliminary antimycobacterial drug discovery study supported the traditional claims of C. patens, A. reticulata, and G. suaveolens in the treatment of mycobacterial infections. Meanwhile, further fractionation is required to characterize the active ingredients. Copyright © 2016.

Simultaneous determination of Ca, Cu, Ni, Zn and Cd binding strengths with fulvic acid fractions by Schubert's method

USGS Publications Warehouse

Brown, G.K.; MacCarthy, P.; Leenheer, J.A.

1999-01-01

The equilibrium binding of Ca2+, Ni2+, Cd2+, Cu2+ and Zn2+ with unfractionated Suwannee river fulvic acid (SRFA) and an enhanced metal binding subfraction of SRFA was measured using Schubert's ion-exchange method at pH 6.0 and at an ionic strength (??) of 0.1 (NaNO3). The fractionation and subfractionation were directed towards obtaining an isolate with an elevated metal binding capacity or binding strength as estimated by Cu2+ potentiometry (ISE). Fractions were obtained by stepwise eluting an XAD-8 column loaded with SRFA with water eluents of pH 1.0 to pH 12.0. Subfractions were obtained by loading the fraction eluted from XAD-8 at pH 5.0 onto a silica gel column and eluting with solvents of increasing polarity. Schuberts ion exchange method was rigorously tested by measuring simultaneously the conditional stability constants (K) of citric acid complexed with the five metals at pH 3.5 and 6.0. The logK of SRFA with Ca2+, Ni2+, Cd2+, Cu2+ and Zn2+ determined simultaneously at pH 6.0 follow the sequence of Cu2+>Cd2+>Ni2+>Zn2+>Ca2+ while all logK values increased for the enhanced metal binding subfraction and followed a different sequence of Cu2+>Cd2+>Ca2+>Ni2+>Zn2+. Both fulvic acid samples and citric acid exhibited a 1:1 metal to ligand stochiometry under the relatively low metal loading conditions used here. Quantitative 13C nuclear magnetic resonance spectroscopy showed increases in aromaticity and ketone content and decreases in aliphatic carbon for the elevated metal binding fraction while the carboxyl carbon, and elemental nitrogen, phosphorus, and sulfur content did not change. The more polar, elevated metal binding fraction did show a significant increase in molecular weight over the unfractionated SRFA. Copyright (C) 1999 Elsevier Science B.V.

Atomic force microscopy-guided fractionation reveals the influence of cranberry phytochemicals on adhesion of Escherichia coli.

PubMed

Gupta, Prachi; Song, Biqin; Neto, Catherine; Camesano, Terri A

2016-06-15

Cranberry juice has been long used to prevent infections because of its effect on the adhesion of the bacteria to the host surface. Proanthocyanidins (PACs) comprise of one of the major classes of phytochemicals found in cranberry, which have been extensively studied and found effective in combating adhesion of pathogenic bacteria. The role of other cranberry constituents in impacting bacterial adhesion haven't been studied very well. In this study, cranberry juice fractions were prepared, characterized and tested for their effect on the surface adhesion of the pathogenic clinical bacterial strain E. coli B78 and non-pathogenic control E. coli HB101. The preparations tested included crude cranberry juice extract (CCE); three fractions containing flavonoid classes including proanthocyanidins, anthocyanins and flavonols; selected sub-fractions, and commercially available flavonol glycoside, quercetin-3-O-galactoside. Atomic force microscopy (AFM) was used to quantify the adhesion forces between the bacterial surface and the AFM probe after the treatment with the cranberry fractions. Adhesion forces of the non-pathogenic, non fimbriated lab strain HB101 are small (average force 0.19 nN) and do not change with cranberry treatments, whereas the adhesion forces of the pathogenic, Dr adhesion E. coli strain B78 (average force of 0.42 nN) show a significant decrease when treated with cranberry juice extract or fractions (average force of 0.31 nN, 0.37 nN and 0.39 nN with CCE, Fraction 7 and Fraction 4 respectively). In particular, the fractions that contained flavonols in addition to PACs were more efficient at lowering the force of adhesion (average force of 0.31 nN-0.18 nN between different sub-fractions containing flavonols and PACs). The sub-fractions containing flavonol glycosides (from juice, fruit and commercial quercetin) all resulted in reduced adhesion of the pathogenic bacteria to the model probe. This strongly suggests the anti adhesive role of other classes of

Functional domains of the T lymphocyte plasma membrane: characterization of the polypeptide composition.

PubMed

Szamel, M; Kaever, V; Resch, K

1987-01-01

Highly purified plasma membranes from calf thymocytes were fractionated by affinity chromatography on Concanavalin A-Sepharose into two subfractions, one eluting freely from the affinity column (MF1) and a second being specifically retained (MF2). SDS-polyacrylamide-gel-electrophoresis revealed different polypeptide patterns of the two plasma membrane subfractions. Polypeptides of apparent molecular weights of 170, 150, 110, 94, 39, and 30 kDa were several-fold enriched in the adherent fraction, MF2. In contrast, several proteins in the 55-65 kDa range were preferentially recovered in the non-adherent fraction. Five Five of the six polypeptides, preferentially recovered in MF2 proved to be glycoproteins, the 39 kDa peptide was non-glycosilated. The differences in the amounts of the polypeptides specifically enriched in the adherent fraction MF2 became even more clear-cut when plasma membranes solubilized with non-ionic detergents (lysolecithin, ET-18-2H, Triton-X-100) were separated by affinity chromatography on Concanavalin A-Sepharose. The non-glycosilated peptide of apparent molecular weight of 39 kDa was recovered together with several glycoproteins in the adherent fraction, MF2, suggesting that not single glycoproteins, but plasma membrane domains were separated by Concanavalin A-Sepharose. Although the glycoproteins of the non-adherent fraction MF1 bound significant amounts of Concanavalin A, the major Concanavalin A binding glycoproteins were recovered in the adherent fraction, MF2. The plasma membrane subfractions showed also different functional properties, the specific activities [Na+ + K+]AT-Pase, Ca2+ ATPase and lysolecithin acyltransferase were several-fold enriched in the adherent fraction, MF2, as compared to MF1. The data suggest the existence of plasma membrane domains in the plasma membranes of thymocytes consisting of a different set of proteins, among others the major Concanavalin A binding glycoproteins with some membrane bound enzymes

Antibacterial activities of the methanol extract, fractions and compounds from Elaeophorbia drupifera (Thonn.) Stapf. (Euphorbiaceae).

PubMed

Voukeng, Igor K; Nganou, Blaise K; Sandjo, Louis P; Celik, Ilhami; Beng, Veronique P; Tane, Pierre; Kuete, Victor

2017-01-07

Elaeophorbia drupifera (Thonn.) Stapf. (Euphorbiaceae) is used in Cameroonian folk medicine to treat several ailments including bacterial-related diseases such as skin infections. In this study, the methanol extract from the leaves (EDL), fractions (EDLa-d), sub-fractions EDLc1-7 and EDLc31-35 as well as isolated compounds were tested for their antimicrobial activities against a panel of Gram-negative and Gram-positive bacteria including multidrug resistant (MDR) phenotypes. The broth microdilution method was used to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the above samples; column chromatography was used for the fractionation and purification of the leaves extract whilst the chemical structures of compounds were determined using spectroscopic techniques. Phytochemical investigation lead to the isolation of a mixture (1:3) of stigmasterol and β-sitosterol (1 + 2), euphol (3), sitosterol-O-β- D -xylopyranoside (4), 3,3',4'-tri-O-methylellagic acid (5), a mixture (1:1) of afzelin and quercetin-3-O-β- D -xylopyranoside (6 + 7), 3,3',4'-tri-O-methylellagic acid 4-O-β- D -glucopyranoside (8), ellagic acid-4-O-β-xylopyranoside-3,3',4'-trimethyl ether (9) from EDLc. Crude extract and fractions displayed selective activities with MIC values ranged from 32 to 1024 μg/mL for EDL against 84.9% of the 33 tested bacteria, 93.9% for EDLc, 69.7% for EDLb, 33.4% for EDLa and 0.03% for EDLd. MIC values ranged from 16 to 1024 μg/mL were obtained with EDLc3 and EDLc4 on all tested bacteria meanwhile other sub-fractions displayed selective activities. MIC value of 32 μg/mL was obtained with fractions EDLa against Escherichia coli AG100, EDLc against Enterobacer aerogenes ATCC13048 and EA298. For sub-fractions obtained from EDLc, the lowest MIC value of 16 μg/mL was recorded with EDLc3 against Staphylococcus aureus MRSA11. A corresponding value of 8 μg/mL against Providencia stuartii NAE16 was recorded with

Increasing protein production rates can decrease the rate at which functional protein is produced

NASA Astrophysics Data System (ADS)

Sharma, Ajeet; O'Brien, Edward

The rate at which soluble, functional protein is produced by the ribosome has recently been found to vary in complex and unexplained ways as various translation-associated rates are altered through synonymous codon substitutions. We combine a well-established ribosome-traffic model with a master-equation model of co-translational domain folding to explore the scenarios that are possible for the protein production rate, J, and the functional-nascent protein production rate, F, as the rates associated with translation are altered. We find that while J monotonically increases as the rates of translation-initiation, -elongation and -termination increase, F can either increase or decrease. F exhibits non-monotonic behavior because increasing these rates can cause a protein to be synthesized more rapidly but provide less time for nascent-protein domains to co-translationally fold thereby producing less functional nascent protein immediately after synthesis. We further demonstrate that these non-monotonic changes in Faffect the post-translational, steady-state levels of functional protein in a similar manner. Our results provide a possible explanation for recent experimental observations that the specific activity of enzymatic proteins can decrease with increased synthesis rates and can in principle be used to rationally-design transcripts to maximize the production of functional nascent protein.

Oligosaccharyltransferase directly binds to ribosome at a location near the translocon-binding site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harada, Y.; Li, H.; Li, Hua

2009-04-28

Oligosaccharyltransferase (OT) transfers high mannose-type glycans to the nascent polypeptides that are translated by the membrane-bound ribosome and translocated into the lumen of the endoplasmic reticulum through the Sec61 translocon complex. In this article, we show that purified ribosomes and OT can form a binary complex with a stoichiometry of {approx}1 to 1 in the presence of detergent. We present evidence that OT may bind to the large ribosomal subunit near the site where nascent polypeptides exit. We further show that OT and the Sec61 complex can simultaneously bind to ribosomes in vitro. Based on existing data and our findings,more » we propose that cotranslational translocation and N-glycosylation of nascent polypeptides are mediated by a ternary supramolecular complex consisting of OT, the Sec61 complex, and ribosomes.« less

Developments and applications of DAQ framework DABC v2

NASA Astrophysics Data System (ADS)

Adamczewski-Musch, J.; Kurz, N.; Linev, S.

2015-12-01

The Data Acquisition Backbone Core (DABC) is a software framework for distributed data acquisition. In 2013 Version 2 of DABC has been released with several improvements. For monitoring and control, an HTTP web server and a proprietary command channel socket have been provided. Web browser GUIs have been implemented for configuration and control of DABC and MBS DAQ nodes via such HTTP server. Several specific plug-ins, for example interfacing PEXOR/KINPEX optical readout PCIe boards, or HADES trbnet input and hld file output, have been further developed. In 2014, DABC v2 was applied for production data taking of the HADES collaboration's pion beam time at GSI. It fully replaced the functionality of the previous event builder software and added new features concerning online monitoring.

Spill Assessment Model (SAM) Procedure for Manual Field Calculations.

DTIC Science & Technology

1980-04-01

34or ~ d 0 <OJ -i~ < 1I/6 z L) C.) 9. I- a. c cu cj El 0 0. 0. 0 0 ~~1~ 3 ci h -z L - 00,0o c 0. Ci) 0 #. .2 a) 13 i __ ______4-- (± 3d ) Hld3(Q 00 o 0 0 r...release rate since for the purpose of expected use it was assumed that inadequate in- formation would be available to accurately characterize a...Io:ot:.n1311 Madten.tepecificHas ofVWpels): S. HEALTH AZARDS Aqar I3 12,,tHit aoV~otrri A5lle~ t1es ,feWP6O 3eutrns: .1 9 Laten I-atdy1p,1 F I en: 0 1k

The force-sensing peptide VemP employs extreme compaction and secondary structure formation to induce ribosomal stalling.

PubMed

Su, Ting; Cheng, Jingdong; Sohmen, Daniel; Hedman, Rickard; Berninghausen, Otto; von Heijne, Gunnar; Wilson, Daniel N; Beckmann, Roland

2017-05-30

Interaction between the nascent polypeptide chain and the ribosomal exit tunnel can modulate the rate of translation and induce translational arrest to regulate expression of downstream genes. The ribosomal tunnel also provides a protected environment for initial protein folding events. Here, we present a 2.9 Å cryo-electron microscopy structure of a ribosome stalled during translation of the extremely compacted VemP nascent chain. The nascent chain forms two α-helices connected by an α-turn and a loop, enabling a total of 37 amino acids to be observed within the first 50-55 Å of the exit tunnel. The structure reveals how α-helix formation directly within the peptidyltransferase center of the ribosome interferes with aminoacyl-tRNA accommodation, suggesting that during canonical translation, a major role of the exit tunnel is to prevent excessive secondary structure formation that can interfere with the peptidyltransferase activity of the ribosome.

Spontaneous remodeling of HDL particles at acidic pH enhances their capacity to induce cholesterol efflux from human macrophage foam cells[S

PubMed Central

Nguyen, Su Duy; Öörni, Katariina; Lee-Rueckert, Miriam; Pihlajamaa, Tero; Metso, Jari; Jauhiainen, Matti; Kovanen, Petri T.

2012-01-01

HDL particles may enter atherosclerotic lesions having an acidic intimal fluid. Therefore, we investigated whether acidic pH would affect their structural and functional properties. For this purpose, HDL2 and HDL3 subfractions were incubated for various periods of time at different pH values ranging from 5.5 to 7.5, after which their protein and lipid compositions, size, structure, and cholesterol efflux capacity were analyzed. Incubation of either subfraction at acidic pH induced unfolding of apolipoproteins, which was followed by release of lipid-poor apoA-I and ensuing fusion of the HDL particles. The acidic pH-modified HDL particles exhibited an enhanced ability to promote cholesterol efflux from cholesterol-laden primary human macrophages. Importantly, treatment of the acidic pH-modified HDL with the mast cell-derived protease chymase completely depleted the newly generated lipid-poor apoA-I, and prevented the acidic pH-dependent increase in cholesterol efflux. The above-found pH-dependent structural and functional changes were stronger in HDL3 than in HDL2. Spontaneous acidic pH-induced remodeling of mature spherical HDL particles increases HDL-induced cholesterol efflux from macrophage foam cells, and therefore may have atheroprotective effects. PMID:22855736

An efficient preparative procedure for main flavonoids from the peel of Trichosanthes kirilowii Maxim. using polyamide resin followed by semi-preparative high performance liquid chromatography.

PubMed

Li, Aifeng; Sun, Ailing; Liu, Renmin; Zhang, Yongqing; Cui, Jichun

2014-08-15

In this study, a simple and efficient preparative procedure was developed for preparation of seven flavonoids from the peel of Trichosanthes kirilowii Maxim. using polyamide resin followed by semi-preparative high performance liquid chromatography (SPHPLC). First, the ethyl acetate fraction from the peel of T. kirilowii Maxim. obtained "prefractionation" using polyamide resin, which yielded two subfractions. And then the two subfractions were isolated by SPHPLC with an isocratic elution of methanol-water. Finally, seven known flavonoids were purified from 35 g of ethyl acetate extract including quercetin-3-O-[α-l-rhamnose (1→2)-β-d-glucopyranosyl]-5-O-β-d-glucopyranoside (19 mg), quercetin-3-O-rutinoside (24 mg), apigenin-7-O-β-d-glucopyranoside (10mg), diosmetin-7-O-β-d-glucopyranoside (45 mg), luteolin (21 mg), apigenin (15 mg), and diosmetin (56 mg). The purities of the compounds were determined by HPLC and the chemical structures were confirmed by UV and NMR analysis. In the present study, a simple, effective, and rapid procedure was established for preparative separation of multiple components from the peel of T. kirilowii Maxim. Furthermore, it was scalable and economical, so it was a promising basis for large-scale preparation of flavonoids from other plant extracts. Copyright © 2014. Published by Elsevier B.V.

Relationships between Degree of Polymerization and Antioxidant Activities: A Study on Proanthocyanidins from the Leaves of a Medicinal Mangrove Plant Ceriops tagal

PubMed Central

Zhou, Hai-Chao; Tam, Nora Fung-yee; Lin, Yi-Ming; Ding, Zhen-Hua; Chai, Wei-Ming; Wei, Shu-Dong

2014-01-01

Tannins from the leaves of a medicinal mangrove plant, Ceriops tagal, were purified and fractionated on Sephadex LH-20 columns. 13C nuclear magnetic resonance (13C-NMR), reversed/normal high performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI MS) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDT-TOF MS) analysis showed that the tannins were predominantly B-type procyanidins with minor A-type linkages, galloyl and glucosyl substitutions, and a degree of polymerization (DP) up to 33. Thirteen subfractions of the procyanidins were successfully obtained by a modified fractionation method, and their antioxidant activities were investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging capacity and ferric reducing antioxidant power (FRAP) method. All these subfractions exhibited potent antioxidant activities, and eleven of them showed significantly different mean DP (mDP) ranging from 1.43±0.04 to 31.77±1.15. Regression analysis demonstrated that antioxidant activities were positively correlative with mDP when around mDP <10, while dropped and then remained at a level similar to mDP = 5 with around 95 µg ml−1 for DPPH scavenging activity and 4 mmol AAE g−1 for FRAP value. PMID:25313980

Nine Different Chemical Species and Action Mechanisms of Pancreatic Lipase Ligands Screened Out from Forsythia suspensa Leaves All at One Time.

PubMed

Chen, Tinggui; Li, Yayun; Zhang, Liwei

2017-05-12

It is difficult to screen out as many active components as possible from natural plants all at one time. In this study, subfractions of Forsythia suspensa leaves were firstly prepared; then, their inhibitive abilities on pancreatic lipase were tested; finally, the highest inhibiting subfraction was screened by self-made immobilized pancreatic lipase. Results showed that nine ligands, including eight inhibitors and one promotor, were screened out all at one time. They were three flavonoids (rutin, IC 50 : 149 ± 6.0 μmol/L; hesperidin, 52.4 μmol/L; kaempferol-3- O -rutinoside, isolated from F. suspensa leaves for the first time, IC 50 notably reached 2.9 ± 0.5 μmol/L), two polyphenols (chlorogenic acid, 3150 ± 120 μmol/L; caffeic acid, 1394 ± 52 μmol/L), two lignans (phillyrin, promoter; arctigenin, 2129 ± 10.5 μmol/L), and two phenethyl alcohol (forsythiaside A, 2155 ± 8.5 μmol/L; its isomer). Their action mechanisms included competitive inhibition, competitive promotion, noncompetitive inhibition, and uncompetitive inhibition. In sum, using the appropriate methods, more active ingredients can be simply and quickly screened out all at one time from a complex natural product system. In addition, F. suspensa leaves contain numerous inhibitors of pancreatic lipase.

Antimutagenic Compounds of White Shrimp (Litopenaeus vannamei): Isolation and Structural Elucidation

PubMed Central

López-Saiz, Carmen-María; Hernández, Javier; Cinco-Moroyoqui, Francisco-Javier; Velázquez, Carlos; Ocaño-Higuera, Víctor-Manuel; Plascencia-Jatomea, Maribel; Robles-Sánchez, Maribel; Machi-Lara, Lorena; Burgos-Hernández, Armando

2016-01-01

According to the World Health Organization, cancer is the main cause of mortality worldwide; thus, the search of chemopreventive compounds to prevent the disease has become a priority. White shrimp (Litopenaeus vannamei) has been reported as a source of compounds with chemopreventive activities. In this study, shrimp lipids were extracted and then fractionated in order to isolate those compounds responsible for the antimutagenic activity. The antimutagenic activity was assessed by the inhibition of the mutagenic effect of aflatoxin B1 on TA98 and TA100 Salmonella tester strains using the Ames test. Methanolic fraction was responsible for the highest antimutagenic activity (95.6 and 95.9% for TA98 and TA100, resp.) and was further separated into fifteen different subfractions (M1–M15). Fraction M8 exerted the highest inhibition of AFB1 mutation (96.5 and 101.6% for TA98 and TA100, resp.) and, after further fractionation, four subfractions M8a, M8b, M8c, and M8d were obtained. Data from 1H and 13C NMR, and mass spectrometry analysis of fraction M8a (the one with the highest antimutagenic activity), suggest that the compound responsible for its antimutagenicity is an apocarotenoid. PMID:27006678

Choosing sides--asymmetric centriole and basal body assembly.

PubMed

Pearson, Chad G

2014-07-01

Centrioles and basal bodies (CBBs) are microtubule-rich cylindrical structures that nucleate and organize centrosomes and cilia, respectively. Despite their apparent ninefold rotational symmetry, the nine sets of triplet microtubules in CBBs possess asymmetries in their morphology and in the structures that associate with them. These asymmetries define the position of nascent CBB assembly, the orientation of ciliary beating, the orientation of spindle poles and the maintenance of cellular geometry. For some of these functions, the orientation of CBBs is first established during new CBB biogenesis when the daughter structure is positioned adjacent to the mother. The mother CBB organizes the surrounding environment that nascent CBBs are born into, thereby providing a nest for the new CBB to develop. Protists, including ciliates and algae, highlight the importance of this environment with the formation of asymmetrically placed scaffolds onto which new basal bodies assemble and are positioned. Recent studies illuminate the positioning of nascent centrioles relative to a modular pericentriolar material (PCM) environment and suggest that, like ciliates, centrosomes organize an immediate environment surrounding centrioles for their biogenesis and positioning. In this Commentary, I will explore the positioning of nascent CBB assembly as the first event in building cellular asymmetries and describe how the environment surrounding both basal bodies and centrioles may define asymmetric assembly. © 2014. Published by The Company of Biologists Ltd.

Choosing sides – asymmetric centriole and basal body assembly

PubMed Central

Pearson, Chad G.

2014-01-01

ABSTRACT Centrioles and basal bodies (CBBs) are microtubule-rich cylindrical structures that nucleate and organize centrosomes and cilia, respectively. Despite their apparent ninefold rotational symmetry, the nine sets of triplet microtubules in CBBs possess asymmetries in their morphology and in the structures that associate with them. These asymmetries define the position of nascent CBB assembly, the orientation of ciliary beating, the orientation of spindle poles and the maintenance of cellular geometry. For some of these functions, the orientation of CBBs is first established during new CBB biogenesis when the daughter structure is positioned adjacent to the mother. The mother CBB organizes the surrounding environment that nascent CBBs are born into, thereby providing a nest for the new CBB to develop. Protists, including ciliates and algae, highlight the importance of this environment with the formation of asymmetrically placed scaffolds onto which new basal bodies assemble and are positioned. Recent studies illuminate the positioning of nascent centrioles relative to a modular pericentriolar material (PCM) environment and suggest that, like ciliates, centrosomes organize an immediate environment surrounding centrioles for their biogenesis and positioning. In this Commentary, I will explore the positioning of nascent CBB assembly as the first event in building cellular asymmetries and describe how the environment surrounding both basal bodies and centrioles may define asymmetric assembly. PMID:24895399

Facilitating Employees' and Students' Process towards Nascent Entrepreneurship

ERIC Educational Resources Information Center

Hietanen, Lenita

2015-01-01

Purpose: The purpose of this paper is to investigate a model for facilitating employees' and full-time, non-business students' entrepreneurial capabilities during their optional entrepreneurship studies at one Finnish Open University. Design/methodology/approach: The case study investigates the course in which transitions from employees or…

Exploring Nascent Entrepreneurial Learning: A Mixed Method Study

ERIC Educational Resources Information Center

Post, Ernie

2014-01-01

One purpose of this study was to add insight to help Small Business Development Center (SBDC) entrepreneurial educators understand why over 40% of their adult learners discontinue their learning program prematurely. In addition, this study explored how the comprehensive Self-Directed Learning (SDL) model might inform our understanding of attrition…

'2A-Like' Signal Sequences Mediating Translational Recoding: A Novel Form of Dual Protein Targeting.

PubMed

Roulston, Claire; Luke, Garry A; de Felipe, Pablo; Ruan, Lin; Cope, Jonathan; Nicholson, John; Sukhodub, Andriy; Tilsner, Jens; Ryan, Martin D

2016-08-01

We report the initial characterization of an N-terminal oligopeptide '2A-like' sequence that is able to function both as a signal sequence and as a translational recoding element. Owing to this translational recoding activity, two forms of nascent polypeptide are synthesized: (i) when 2A-mediated translational recoding has not occurred: the nascent polypeptide is fused to the 2A-like N-terminal signal sequence and the fusion translation product is targeted to the exocytic pathway, and, (ii) a translation product where 2A-mediated translational recoding has occurred: the 2A-like signal sequence is synthesized as a separate translation product and, therefore, the nascent (downstream) polypeptide lacks the 2A-like signal sequence and is localized to the cytoplasm. This type of dual-functional signal sequence results, therefore, in the partitioning of the translation products between the two sub-cellular sites and represents a newly described form of dual protein targeting. © 2016 The Authors. Traffic published by John Wiley & Sons Ltd.

The force-sensing peptide VemP employs extreme compaction and secondary structure formation to induce ribosomal stalling

PubMed Central

Su, Ting; Cheng, Jingdong; Sohmen, Daniel; Hedman, Rickard; Berninghausen, Otto; von Heijne, Gunnar; Wilson, Daniel N; Beckmann, Roland

2017-01-01

Interaction between the nascent polypeptide chain and the ribosomal exit tunnel can modulate the rate of translation and induce translational arrest to regulate expression of downstream genes. The ribosomal tunnel also provides a protected environment for initial protein folding events. Here, we present a 2.9 Å cryo-electron microscopy structure of a ribosome stalled during translation of the extremely compacted VemP nascent chain. The nascent chain forms two α-helices connected by an α-turn and a loop, enabling a total of 37 amino acids to be observed within the first 50–55 Å of the exit tunnel. The structure reveals how α-helix formation directly within the peptidyltransferase center of the ribosome interferes with aminoacyl-tRNA accommodation, suggesting that during canonical translation, a major role of the exit tunnel is to prevent excessive secondary structure formation that can interfere with the peptidyltransferase activity of the ribosome. DOI: http://dx.doi.org/10.7554/eLife.25642.001 PMID:28556777

Prevalence, antibiotic resistance, virulence traits and genetic lineages of Staphylococcus aureus in healthy sheep in Tunisia.

PubMed

Gharsa, Haythem; Ben Slama, Karim; Lozano, Carmen; Gómez-Sanz, Elena; Klibi, Naouel; Ben Sallem, Rym; Gómez, Paula; Zarazaga, Myriam; Boudabous, Abdellatif; Torres, Carmen

2012-05-04

Nasal swabs of 163 healthy sheep were obtained from two farms and one abattoir in Tunisia during 2010. Samples were inoculated in Baird Parker agar and ORSAB medium for Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) recovery, respectively. MRSA was detected in 5 of these 163 samples (3%) in ORSAB medium, and one isolate per sample was further studied. MRSA isolates were mecA-positive, typed as ST153-CC80-t044-agrIII, and contained blaZ, ant(6)-Ia, aph(3')-IIIa, erm(C), tet(K), and fusB genes encoding penicillin, streptomycin, kanamycin, erythromycin, tetracycline and fusidic acid resistance, respectively. These MRSA isolates showed indistinguishable or closely related PFGE-patterns and harboured the lukF/lukS gene encoding the Panton-Valentine leukocidin and the luk-ED, hla, hld, and hlg(v) genes. Methicillin-susceptible S. aureus (MSSA) were recovered in 68 of the 163 samples (41.7%) and one isolate per sample was characterized. Most of MSSA (82.4%) showed susceptibility to the tested antibiotics with exceptions: penicillin (6%, carrying blaZ gene), tetracycline (19%, carrying tet(K) gene) and fusidic acid (9%). The following toxin-genes were identified among MSSA: tst (53 isolates), luk-M (52), luk-ED, hla, hlb, hld and hlg(v) (67), hlg (1), sec (49), sel (52), and the egc-cluster-like sen-sem-sei-seo-seg (1). Ten spa-types (two of them new ones) and nine sequence types (six new ones) were detected among the 73 S. aureus isolates, and they were ascribed to agr types I and III. All MRSA and MSSA isolates were able to coagulate bovine plasma and MRSA harboured the immune-evasion-gene-cluster type E. Conclusions. Nares of healthy sheep could be a reservoir of PVL-positive community-associated-MRSA and also of TSST-positive S. aureus isolates, with potential implications in public health. Copyright © 2011 Elsevier B.V. All rights reserved.

Bioactive components and mechanisms of Chinese poplar propolis alleviates oxidized low-density lipoprotein-induced endothelial cells injury.

PubMed

Chang, Huasong; Yuan, Wenwen; Wu, Haizhu; Yin, Xusheng; Xuan, Hongzhuan

2018-05-03

Propolis, a polyphenol-rich natural product, has been used as a functional food in anti-inflammation. However, its bioactive components and mechanisms have not been fully elucidated. To discover the bioactive components and anti-inflammatory mechanism, we prepared and separated 8 subfractions from ethyl acetate extract of Chinese propolis (EACP) and investigated the mechanism in oxidized low density lipoprotein (ox-LDL) induced human umbilical vein endothelial cells (HUVECs) damage. Eight subfractions were prepared and separated from ethyl acetate extract of Chinese propolis (EACP) with different concentrations of methanol-water solution, and analysed its chemical constituents by HPLC-DAD/Q-TOF-MS. Then 80% confluent HUVECs were stimulated with 40 μg/mL ox-LDL. Cell viability and apoptosis were evaluated by Sulforhodamine B (SRB) assay and Hoechst 33,258 staining, respectively. Levels of caspase 3, PARP, LC3B, p62, p-mTOR, p-p70S6K, p-PI3K, p-Akt, LOX-1 and p-p38 MAPK were assessed by western blotting and immunofluorescence assay, respectively. Reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were measured with fluorescent probes. Each subfraction exhibited similar protective effect although the contents of chemical constituents were different. EACP attenuated ox-LDL induced HUVECs apoptosis, depressed the ratio of LC3-II/LC3-I and enhanced the p62 level. In addition, treatment with EACP also activated the phosphorylation of PI3K/Akt/mTOR, and deactivated the level of LOX-1 and phosphorylation of p38 MAPK. The overproduction of ROS and the damage of MMP were also ameliorated after ECAP treatment. These findings indicated that the bioactive component of propolis on anti-inflammatory activity was not determined by a single constituent, but a complex interaction including flavonoids, esters and phenolic acids. EACP attenuated ox-LDL induced HUVECs injury by inhibiting LOX-1 level and depressed ROS production against oxidative stress in ox

Antibacterial activity of Pinus elliottii against anaerobic bacteria present in primary endodontic infections.

PubMed

Caetano da Silva, Sandro Donizete; Mendes de Souza, Maria Gorete; Oliveira Cardoso, Miguel Jorge; da Silva Moraes, Thais; Ambrósio, Sérgio Ricardo; Sola Veneziani, Rodrigo Cássio; Martins, Carlos Henrique G

2014-12-01

Endodontic infections have a polymicrobial nature, but anaerobic bacteria prevail among the infectious microbes. Considering that it is easy to eliminate planktonic bacteria, biofilm-forming bacteria still challenge clinicians during the fight against endodontic diseases. The chemical constituents of the oleoresin of Pinus elliottii, a plant belonging to the family Pinaceae, stand out in the search for biologically active compounds based on natural products with potential application in the treatment of endodontic infections. Indeed, plant oleoresins are an abundant natural source of diterpenes that display significant and well-defined biological activities as well as potential antimicrobial action. In this context, this study aimed to (1) evaluate the in vitro antibacterial activity of the oleoresin, fractions, and subfractions of P. elliottii as well as the action of dehydroabietic acid against 11 anaerobic bacteria that cause endodontic infection in both their planktonic and biofilm forms and (2) assess the in vitro antibiofilm activity of dehydroabietic acid against the same group of bacteria. The broth microdilution technique helped to determine the minimum inhibitory concentration (MIC) of the oleoresin and fractions. This same technique aided determination of the MIC values of nine subfractions of Fraction 1, the most active fraction. The MIC, minimum bactericidal concentration, and antibiofilm activity of dehydroabietic acid against the tested anaerobic bacteria were also examined. The oleoresin and fractions, especially fraction PE1, afforded promising MIC values, which ranged from 0.4 to 50 μg/mL. Concerning the nine evaluated subfractions, PE1.3 and PE1.4 furnished the most noteworthy MIC values, between 6.2 and 100 μg/mL. Dehydroabietic acid displayed antibacterial activity, with MIC values lying from 6.2 to 50 μg/mL, as well as bactericidal effect for all the investigated bacteria, except for Prevotella nigrescens. Assessment of the antibiofilm

Ophiamides A-B, new potent urease inhibitory sphingolipids from Heliotropium ophioglossum.

PubMed

Firdous, Sadiqa; Ansari, Nida Hassan; Fatima, Itrat; Malik, Abdul; Afza, Nighat; Iqbal, Lubna; Lateef, Mehreen

2012-07-01

Ophiamides A (1) and B (2), two new sphingolipids have been isolated from the n-hexane subfraction of the MeOH extract of the whole plant of Heliotropium ophioglossum along with glycerol monopalmitate (3) and β-sitosterol 3-O-β-D: -glucoside (4) reported for the first time from this species. Their structures were elucidated by spectroscopic techniques including MS and 2D-NMR spectroscopy. Both the compounds 1 and 2 showed potent inhibitory activity against the enzyme urease.

The use of centrifugation to study early Drosophila embryogenesis

NASA Technical Reports Server (NTRS)

Abbott, M. K.; Spooner, B. S. (Principal Investigator)

1993-01-01

By the end of 10th nuclear cycle, the somatic nuclei of the Drosophila embryo have migrated to the periphery of the egg. Centrifugation of embryos did not result in the displacement of these nuclei, since cytoskeletal elements anchor them to the cortex. But, mild centrifugal forces displace the centrally located, nascent yolk nuclei. If this increased sensitivity to hypergravity occurs before the beginning of nuclear differentiation during cycle 8, when the nascent yolk and somatic nuclei physically separate, then it would mark the earliest functional difference between these two lineages.

Unesterified plant sterols and stanols do not affect LDL electrophoretic characteristics in hypercholesterolemic subjects.

PubMed

Charest, Amélie; Desroches, Sophie; Vanstone, Catherine A; Jones, Peter J H; Lamarche, Benoît

2004-03-01

The extent to which sterols and stanols modulate LDL particle size is unknown. We examined the effects of supplementation with unesterified plant sterols and stanols on several LDL electrophoretic characteristics. Healthy hypercholesterolemic subjects (n = 14) consumed each of four experimental diets contained plant sterols (S), plant stanols (SN), a 50:50 mixture of sterols and stanols (SSN), or cornstarch (control) in a randomized crossover design. The butter component of the diet was blended with unesterified sterols and stanols at a dose of 1.8 g/d. The LDL particles were characterized by polyacrylamide gradient gel electrophoresis of whole plasma. LDL cholesterol (LDL-C) concentrations decreased by 8.8, 13.6, and 13.1% in the S, SN, and SSN groups, respectively (P < 0.01) with a significant increase of 4.3% in the control group. None of the treatments with sterols and stanols induced significant changes in LDL peak particle diameter or in the cholesterol levels of the small LDL subfraction (<25.5 nm). The reduction in plasma LDL-C levels with SN consumption was due mainly to a decrease (P < 0.05) in the concentration of cholesterol in the large subfraction (>26.0 nm). The significant reduction in plasma LDL-C concentrations by sterol and stanol consumption in subjects was not paralleled by any beneficial changes in LDL electrophoretic characteristics.

Nutrient content and nutrient availability of sorghum wet distiller's grain in comparison with the parental grain for ruminants.

PubMed

Trujillo, Ana I; Bruni, María; Chilibroste, Pablo

2017-06-01

The present study aimed to compare wet sorghum distiller's grain (WSDG) with sorghum grain (SG) in terms of: (i) chemical composition; (ii) in situ rumen degradation kinetics of organic matter (OM) and neutral detergent fiber (NDF); (iii) crude protein (CP) sub-fractions; (iv) in situ disappearance at 12 and 48 h; and (v) energy values. The WSDG intestinal digestibility (ID) of undegradable crude protein (UCP) was compared to soybean meal (SBM). Compared to SG, WSDG exhibited: (i) lower (P < 0.01) dry matter and non-fiber carbohydrate content, whereas the other chemical components were higher (P < 0.01); (ii) higher (P < 0.01) degradation rates of OM and NDF and lower (P < 0.01) degradable fraction of OM and NDF; (iii) lower (P < 0.05) contents of CP sub-fractions A, B1 and B2, and higher (P < 0.05) contents of B3 and C; (iv) lower (P < 0.05) protein disappearance at 12 and 48 h and higher UCP; and (v) lower (P < 0.05) energy content. The ID of UCP for WSDG was lower (P < 0.05) compared to SBM. The WSDG as a supplement provides a good source of energy. To enable its use as a protein supplement, further studies should be performed. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Genotoxicity and osteogenic potential of sulfated polysaccharides from Caulerpa prolifera seaweed.

PubMed

Chaves Filho, Gildácio Pereira; de Sousa, Angélica Fernandes Gurgel; Câmara, Rafael Barros Gomes; Rocha, Hugo Alexandre Oliveira; de Medeiros, Silvia Regina Batistuzzo; Moreira, Susana Margarida Gomes

2018-07-15

Marine algae are sources of novel bioactive molecules and present a great potential for biotechnological and biomedical applications. Although green algae are the least studied type of seaweed, several of their biological activities have already been described. Here, we investigated the osteogenic potential of Sulfated Polysaccharide (SP)-enriched samples extracted from the green seaweed Caulerpa prolifera on human mesenchymal stem cells isolated from Wharton jelly (hMSC-WJ). In addition, the potential genotoxicity of these SPs was determined by cytokinesis-block micronucleus (CBMN) assay. SP-enriched samples did not show significant cytotoxicity towards hMSCs-WJ at a concentration of up to 10μg/mL, and after 72h of exposure. SP enrichment also significantly increased alkaline phosphatase (ALP) activity, promoting calcium accumulation in the extracellular matrix. Among the SP-enriched samples, the CP0.5 subfraction (at 5μg/mL) presented the most promising results. In this sample, ALP activity was increased approximately by 60%, and calcium accumulation was approximately 6-fold above the negative control, indicating high osteogenic potential. This subfraction also proved to be non-genotoxic, according to the CBMN assay, as it did not induce micronuclei. The results of this study highlight, for the first time, the potential of these SPs for the development of new therapies for bone regeneration. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of young barley leaf extract and antioxidative vitamins on LDL oxidation and free radical scavenging activities in type 2 diabetes.

PubMed

Yu, Y-M; Chang, W-C; Chang, C-T; Hsieh, C-L; Tsai, C E

2002-04-01

The effects of supplementation of young barley leaf extract (BL) and/or antioxidative vitamins C and E on different low-density lipoprotein (LDL) subfractions susceptibility to oxidation and free radical scavenging activities in patients with type 2 diabetes were evaluated. Thirty-six type 2 diabetic patients were enrolled in this study. The subjects received one of the following supplements daily for 4 weeks: 15 g BL, 200 mg vitamin C and 200 mg vitamin E (CE), or BL plus CE (BL + CE). The lucigenin-chemiluminescence (CL) and luminol-CL levels in blood were significantly reduced in all groups. Vitamin E content of LDL subfractions increased significantly following supplements, especially for BL + CE group. The percent increase of lag times in the BL + CE was significantly higher than those in the BL or CE group. The antioxidative effect of BL + CE was the greatest for small, dense LDL (Sd-LDL) with further increases in percentage of lag times 4 folds compared to BL alone. Our results indicate that supplementation with BL may help to scavenge oxygen free radicals, save the LDL-vitamin E content, and inhibit LDL oxidation. Furthermore, the addition of vitamins C and E to BL can inhibit the Sd-LDL oxidation more effectively, which may protect against vascular diseases in type 2 diabetic patients.

Antimicrobial activity of fermented Theobroma cacao pod husk extract.

PubMed

Santos, R X; Oliveira, D A; Sodré, G A; Gosmann, G; Brendel, M; Pungartnik, C

2014-09-26

Theobroma cacao L. contains more than 500 different chemical compounds some of which have been traditionally used for their antioxidant, anti-carcinogenic, immunomodulatory, vasodilatory, analgesic, and antimicrobial activities. Spontaneous aerobic fermentation of cacao husks yields a crude husk extract (CHE) with antimicrobial activity. CHE was fractioned by solvent partition with polar solvent extraction or by silica gel chromatography and a total of 12 sub-fractions were analyzed for chemical composition and bioactivity. CHE was effective against the yeast Saccharomyces cerevisiae and the basidiomycete Moniliophthora perniciosa. Antibacterial activity was determined using 6 strains: Staphylococcus aureus, Staphylococcus epidermidis, and Bacillus subtilis (Gram-positive) and Pseudomonas aeruginosa, Klebsiella pneumoniae, and Salmonella choleraesuis (Gram-negative). At doses up to 10 mg/mL, CHE was not effective against the Gram-positive bacteria tested but against medically important P. aeruginosa and S. choleraesuis with a minimum inhibitory concentration (MIC) of 5.0 mg/mL. Sub-fractions varied widely in activity and strongest antibacterial activity was seen with CHE8 against S. choleraesuis (MIC of 1.0 mg/mL) and CHE9 against S. epidermidis (MIC of 2.5 mg/mL). All bioactive CHE fractions contained phenols, steroids, or terpenes, but no saponins. Fraction CHE9 contained flavonoids, phenolics, steroids, and terpenes, amino acids, and alkaloids, while CHE12 had the same compounds but lacked flavonoids.

Molecular structures and metabolic characteristics of protein in brown and yellow flaxseed with altered nutrient traits.

PubMed

Khan, Nazir Ahmad; Booker, Helen; Yu, Peiqiang

2014-07-16

The objectives of this study were to investigate the chemical profiles; crude protein (CP) subfractions; ruminal CP degradation characteristics and intestinal digestibility of rumen undegraded protein (RUP); and protein molecular structures using molecular spectroscopy of newly developed yellow-seeded flax (Linum usitatissimum L.). Seeds from two yellow flaxseed breeding lines and two brown flaxseed varieties were evaluated. The yellow-seeded lines had higher (P < 0.001) contents of oil (44.54 vs 41.42% dry matter (DM)) and CP (24.94 vs 20.91% DM) compared to those of the brown-seeded varieties. The CP in yellow seeds contained lower (P < 0.01) contents of true protein subfraction (81.31 vs 92.71% CP) and more (P < 0.001) extensively degraded (70.8 vs 64.9% CP) in rumen resulting in lower (P < 0.001) content of RUP (29.2 vs 35.1% CP) than that in the brown-seeded varieties. However, the total supply of digestible RUP was not significantly different between the two seed types. Regression equations based on protein molecular structural features gave relatively good estimation for the contents of CP (R(2) = 0.87), soluble CP (R(2) = 0.92), RUP (R(2) = 0.97), and intestinal digestibility of RUP (R(2) = 0.71). In conclusion, molecular spectroscopy can be used to rapidly characterize feed protein molecular structures and predict their nutritive value.

An investigation of interurban variations in the chemical composition and mutagenic activity of airborne particulate organic matter using an integrated chemical class/bioassay system

NASA Astrophysics Data System (ADS)

Butler, J. P.; Kneip, T. J.; Daisey, J. M.

Previous investigations in this laboratory have demonstrated that the mutagenic activities of extractable particulate organic matter (EOM) from cities which differ in their principal fuels and meteorology can vary significantly. To gain a better understanding of these interurban variations, an Integrated Chemical Class/Biological Screening System was developed and used for a more detailed examination of differences in the chemical composition and mutagenic activity of EOM. The screening system involved coupling in situ Ames mutagenicity determinations on high performance thin layer chromatography (HPTLC) plates with class specific chemical analyses on a second set of plates. The system was used to screen for mutagenic activity and selected chemical classes (including PAH, nitro-PAH, phenols, carboxylic acids, carbonyls, aza-arenes and alkylating agents) in EOM from the following sites: New York City; Elizabeth, N.J.; Mexico City; Beijing, China; Philadelphia, PA; and the Caldecott Tunnel (CA). The results of this study demonstrated mutagenic activity and chemical compositional differences in HPTLC subfractions of particulate organic matter from these cities and from the Caldecott Tunnel. The greatest interurban differences in chemical classes were observed for the phenols, carbonyl compounds and alkylating agents. Interurban variations in mutagenic activities were greatest for EOM subfractions of intermediate polarity. These differences are probably related to interurban differences in the fuels used, types of sources and atmospheric conditions. The relationships between these variables are not well understood at present.

Highly hydrogenated graphene via active hydrogen reduction of graphene oxide in the aqueous phase at room temperature.

PubMed

Sofer, Zdeněk; Jankovský, Ondřej; Šimek, Petr; Soferová, Lýdie; Sedmidubský, David; Pumera, Martin

2014-02-21

Hydrogenated graphene and graphane are in the forefront of graphene research. Hydrogenated graphene is expected to exhibit ferromagnetism, tunable band gap, fluorescence, and high thermal and low electrical conductivity. Currently available techniques for fabrication of highly hydrogenated graphene use either a liquid ammonia (-33 °C) reduction pathway using alkali metals or plasma low pressure or ultra high pressure hydrogenation. These methods are either technically challenging or pose inherent risks. Here we wish to demonstrate that highly hydrogenated graphene can be prepared at room temperature in the aqueous phase by reduction of graphene oxide by nascent hydrogen generated by dissolution of metal in acid. Nascent hydrogen is known to be a strong reducing agent. We studied the influence of metal involved in nascent hydrogen generation and characterized the samples in detail. The resulting reduced graphenes and hydrogenated graphenes were characterized in detail. The resulting hydrogenated graphene had the chemical formula C1.16H1O0.66. Such simple hydrogenation of graphene is of high importance for large scale safe synthesis of hydrogenated graphene.

Environmental Staphylococcus aureus contamination in a Tunisian hospital.

PubMed

Gharsa, Haythem; Dziri, Raoudha; Klibi, Naouel; Chairat, Sarra; Lozano, Carmen; Torres, Carmen; Bellaaj, Ridha; Slama, Karim Ben

2016-12-01

One hundred hospital environment samples were obtained in 2012 in a Tunisian hospital and tested for Staphylococcus aureus recovery. Antimicrobial resistance profile and virulence gene content were determined. Multilocus-sequence-typing (MLST), spa-typing, agr-typing and SmaI-pulsed-field gel electrophoresis (PFGE) were performed. Two methicillin-resistant S. aureus (MRSA) isolates typed as: ST247-t052-SCCmecI-agrI were recovered from the intensive care unit (ICU). Ten samples contained methicillin-susceptible S. aureus (MSSA) and these samples were collected in different services, highlighting the presence of the tst gene encoding the toxic shock syndrome toxin as well as the lukED, hla, hlb, hld and hlg v virulence genes in some of the isolates. In conclusion, we have shown that the hospital environment could be a reservoir contributing to dissemination of virulent S. aureus and MRSA.

Health Security Intelligence: Assessing the Nascent Public Health Capability

DTIC Science & Technology

2012-03-01

and one that although dedicated as an HSI analyst, did not work a full 40- hour workweek . Of the three jurisdictions that answered yes to Question 6...during the standard 40- hour workweek is well established. In her book, Out of Bounds, Innovation and Change in Law Enforcement Intelligence Analysis...collection of information is estimated to average 1 hour per response, including the time for reviewing instruction, searching existing data sources

Sequential protein association with nascent 60S ribosomal particles.

PubMed

Saveanu, Cosmin; Namane, Abdelkader; Gleizes, Pierre-Emmanuel; Lebreton, Alice; Rousselle, Jean-Claude; Noaillac-Depeyre, Jacqueline; Gas, Nicole; Jacquier, Alain; Fromont-Racine, Micheline

2003-07-01

Ribosome biogenesis in eukaryotes depends on the coordinated action of ribosomal and nonribosomal proteins that guide the assembly of preribosomal particles. These intermediate particles follow a maturation pathway in which important changes in their protein composition occur. The mechanisms involved in the coordinated assembly of the ribosomal particles are poorly understood. We show here that the association of preribosomal factors with pre-60S complexes depends on the presence of earlier factors, a phenomenon essential for ribosome biogenesis. The analysis of the composition of purified preribosomal complexes blocked in maturation at specific steps allowed us to propose a model of sequential protein association with, and dissociation from, early pre-60S complexes for several preribosomal factors such as Mak11, Ssf1, Rlp24, Nog1, and Nog2. The presence of either Ssf1 or Nog2 in complexes that contain the 27SB pre-rRNA defines novel, distinct pre-60S particles that contain the same pre-rRNA intermediates and that differ only by the presence or absence of specific proteins. Physical and functional interactions between Rlp24 and Nog1 revealed that the assembly steps are, at least in part, mediated by direct protein-protein interactions.

Nascent Marine Aerosol Acting as Ultra-Efficient Cloud Nuclei

NASA Astrophysics Data System (ADS)

Ovadnevaite, J.; Zuend, A.; Laaksonen, A.; Sanchez, K.; Roberts, G.; Ceburnis, D.; Decesari, S.; Rinaldi, M.; Hodas, N.; Facchini, C.; Seinfeld, J.; O'Dowd, C. D. D.

2017-12-01

Marine aerosol is an important part of the natural aerosol and often dominates the total burden in remote locations. Moreover, it contributes significantly to the global radiative budget through the formation of haze and cloud layers. Even if these layers are optically-thin at times, they can have a profound impact on the radiative budget as they overly a dark and extensive ocean surface. Since the postulation of marine aerosol global importance several decades ago1, understanding has progressed from evaluation of the nss-sulphate and sea salt effects to the acknowledgement of a significant role of organic aerosol2. Dependence of organic matter (OM) fraction enrichment in sea spray on phytoplankton biomass has been shown3 as well as an apparent dichotomous OM behaviour in terms of water uptake4. Hygroscopicity of organic aerosol in sub-saturated humidity fields is typically less than most common salts found in the atmospheric aerosol; however, the ability of organic aerosol to activate cloud droplets is predicted to be greatly increased in supersaturated air due a lowering of the droplets surface tension5. While this phenomenon has been acknowledged for some time, it has yet to be demonstrated in the real atmosphere. Here, we present evidence that recently-formed secondary organic aerosol particles, in marine air, lead to enhanced cloud droplet activation resulting from surface tension reduction. Whilst the surface tension lowering is expected to be negated by a concomitant reduction in the Raoult effect, driven by the displacement of solute ions by surfactant molecules at the droplet-vapour interface, we present new observational and theoretical evidence illustrating that, in ambient air, the former can prevail over the latter. Consideration of liquid-liquid phase-separation, leading to complete or partial engulfing of a hygroscopic particle core by a hydrophobic organic-rich phase, explains the lack of suppression of the Raoult effect, while maintaining substantial surface tension lowering and resulting in a tenfold increase in predicted CCN number concentration. 1Charlson R. J. et al. Nature 326, 655-661, 1987; 2O'Dowd C. D. et al. Nature 431, 676-680, 2004; 3O'Dowd C. et al. Scientific Reports 5, 2015; 4Ovadnevaite J. et al. Geophys Res Lett 38, 2011; 5Facchini M. C. et al. Atmos Environ 34, 4853-4857, 2000.

Correlating shaped charge performance with processing conditions and microstructure of an aluminum alloy 1100 liner enabled by a new method to arrest nascent jet formation

NASA Astrophysics Data System (ADS)

Scheid, James Eric

Aluminum-lined shaped charges are used in special applications where jet and / or slug residue in the target is undesired. The three different microstructures of the aluminum liners studied herein resulted from three different manufacturing interpretations of the same design. One interpretation was completely machining the liners from best available annealed round stock. The second was to cold-forge the liners from annealed round-stock in an open-die forge to near-final dimensions, and then machine the liners to the final dimensions. The third variant in this study was to use the above forged liner, but with annealing after the machining. These three manufacturing choices resulted in significant variations in shaped charge performance. The goal of this research was to clarify the relationships between the liner metal microstructure and properties, and the corresponding shaped charge dynamic flow behavior. What began as an investigation into user-reported performance problems associated inherently with liner manufacturing processes and resultant microstructure, resolved into new understandings of the relationships between aluminum liner microstructure and shaped charge collapse kinetics. This understanding was achieved through an extensive literature review and the comprehensive characterization of the material properties of three variants of an 1100 aluminum shaped charge liner with a focus on collapse and nascent jet formation. The machined liner had a microstructure with large millimeter-sized grains and fine particles aligned in bands parallel to the charge axis. The forged liner microstructure consisted of very small one micrometer-sized (1 mum) subgrains and fine particles aligned largely in bands elongated parallel to the liner contour. The annealed liner was characterized by ten micrometer (10 mum) sized equiaxed grains with residual fine particles in the forged alignment. This characterization was enabled by the development, execution and validation of a

Subduction-related cryptic metasomatism in fore-arc to nascent fore-arc Neoproterozoic mantle peridotites beneath the Eastern Desert of Egypt: mineral chemical and geochemical evidences

NASA Astrophysics Data System (ADS)

Hamdy, Mohamed; Salam Abu El-Ela, Abdel; Hassan, Adel; Kill, Youngwoo; Gamal El Dien, Hamed

2013-04-01

Mantle spinel peridotites beneath the Arabian Nubian Shield (ANS) in the Eastern Desert (ED) of Egypt were formed in arc stage in different tectonic setting. Thus they might subject to exchange with the crustal material derived from recycling subducting oceanic lithosphere. This caused metasomatism enriching the rocks in incompatible elements and forming non-residual minerals. Herein, we present mineral chemical and geochemical data of four ophiolitic mantle slice serpentinized peridotites (W. Mubarak, G. El-Maiyit, W. Um El Saneyat and W. Atalla) widely distributed in the ED. These rocks are highly serpentinized, except some samples from W. Mubarak and Um El-Saneyat, which contain primary olivine (Fo# = 90-92 mol %) and orthopyroxene (En# = 86-92 mol %) relics. They have harzburgite composition. Based on the Cr# and Mg# of the unaltered spinel cores, all rocks formed in oceanic mantle wedge in the fore-arc setting, except those from W. Atalla formed in nascent fore-arc. This implies that the polarity of the subduction during the arc stage was from the west to the east. These rocks are restites formed after partial melting between 16.58 in W. Atalla to 24 % in G-El Maiyit. Melt extraction occurred under oxidizing conditions in peridotites from W. Mubarak and W. Atalla and under reducing conditions in peridotites from G. El-Maiyit and Um El-Saneyat. Cryptic metasomatism in the studied mantle slice peridotites is evident. This includes enrichment in incompatible elements in minerals and whole rocks if compared with the primitive mantle (PM) composition and the trend of the depletion in melt. In opx the Mg# doesn't correlate with TiO2, CaO, MnO, NiO and Cr2O3concentrations. In addition, in serpentinites from W. Mubarak and W. Atalla, the TiO2spinel is positively correlated with the TiO2 whole-rock, proposing enrichment by the infiltration of Ti-rich melts, while in G. El- Maiyit and Um El-Saneyat serpentinites they are negatively correlated pointing to the reaction

Electronegative Low-Density Lipoprotein Increases C-Reactive Protein Expression in Vascular Endothelial Cells through the LOX-1 Receptor

PubMed Central

Chu, Chih-Sheng; Wang, Yu-Chen; Lu, Long-Sheng; Walton, Brian; Yilmaz, H. Ramazan; Huang, Roger Y.; Sawamura, Tatsuya; Dixon, Richard A. F.; Lai, Wen-Ter; Chen, Chu-Huang; Lu, Jonathan

2013-01-01

Objectives Increased plasma C-reactive protein (CRP) levels are associated with the occurrence and severity of acute coronary syndrome. We investigated whether CRP can be generated in vascular endothelial cells (ECs) after exposure to the most electronegative subfraction of low-density lipoprotein (LDL), L5, which is atherogenic to ECs. Because L5 and CRP are both ligands for the lectin-like oxidized LDL receptor-1 (LOX-1), we also examined the role of LOX-1. Methods and Results Plasma LDL samples isolated from asymptomatic hypercholesterolemic (LDL cholesterol [LDL-C] levels, 154.6±20 mg/dL; n = 7) patients and normocholesterolemic (LDL-C levels, 86.1±21 mg/dL; P<0.001; n = 7) control individuals were chromatographically resolved into 5 subfractions, L1-L5. The L5 percentage (L5%) and the plasma L5 concentration ([L5]  =  L5% × LDL-C) in the patient and control groups were 8.1±2% vs. 2.3±1% (P<0.001) and 12.6±4 mg/dL vs. 1.9±1 mg/dL (P<0.001), respectively. In hypercholesterolemic patients treated with atorvastatin for 6 months (10 mg/day), [L5] decreased from 12.6±4 mg/dL to 4.5±1.1 mg/dL (P = 0.011; n = 5), whereas both [L5] and L5% returned to baseline levels in 2 noncompliant patients 3 months after discontinuation. In cultured human aortic ECs (HAECs), L5 upregulated CRP expression in a dose- and time-dependent manner up to 2.5-fold (P<0.01), whereas the least electronegative subfraction, L1, had no effect. DiI-labeled L1, internalized through the LDL receptor, became visible inside HAECs within 30 seconds. In contrast, DiI-labeled L5, internalized through LOX-1, became apparent after 5 minutes. L5-induced CRP expression manifested at 30 minutes and was attenuated by neutralizing LOX-1. After 30 minutes, L5 but not L1 induced reactive oxygen species (ROS) production. Both L5-induced ROS and CRP production were attenuated by ROS inhibitor N-acetyl cysteine. Conclusions Our results suggest that CRP, L5, and LOX-1 form a cyclic

Monitoring of the spatial and temporal dynamics of BER/SSBR pathway proteins, including MYH, UNG2, MPG, NTH1 and NEIL1-3, during DNA replication.

PubMed

Bj Rås, Karine Ø; Sousa, Mirta M L; Sharma, Animesh; Fonseca, Davi M; S Gaard, Caroline K; Bj Rås, Magnar; Otterlei, Marit

2017-08-21

Base lesions in DNA can stall the replication machinery or induce mutations if bypassed. Consequently, lesions must be repaired before replication or in a post-replicative process to maintain genomic stability. Base excision repair (BER) is the main pathway for repair of base lesions and is known to be associated with DNA replication, but how BER is organized during replication is unclear. Here we coupled the iPOND (isolation of proteins on nascent DNA) technique with targeted mass-spectrometry analysis, which enabled us to detect all proteins required for BER on nascent DNA and to monitor their spatiotemporal orchestration at replication forks. We demonstrate that XRCC1 and other BER/single-strand break repair (SSBR) proteins are enriched in replisomes in unstressed cells, supporting a cellular capacity of post-replicative BER/SSBR. Importantly, we identify for the first time the DNA glycosylases MYH, UNG2, MPG, NTH1, NEIL1, 2 and 3 on nascent DNA. Our findings suggest that a broad spectrum of DNA base lesions are recognized and repaired by BER in a post-replicative process. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Strolling Toward New Concepts.

PubMed

Ito, Koreaki

2016-09-08

For more than four decades now, I have been studying how genetic information is transformed into protein-based cellular functions. This has included investigations into the mechanisms supporting cellular localization of proteins, disulfide bond formation, quality control of membranes, and translation. I tried to extract new principles and concepts that are universal among living organisms from our observations of Escherichia coli. While I wanted to distill complex phenomena into basic principles, I also tried not to overlook any serendipitous observations. In the first part of this article, I describe personal experiences during my studies of the Sec pathway, which have centered on the SecY translocon. In the second part, I summarize my views of the recent revival of translation studies, which has given rise to the concept that nonuniform polypeptide chain elongation is relevant for the subsequent fates of newly synthesized proteins. Our studies of a class of regulatory nascent polypeptides advance this concept by showing that the dynamic behaviors of the extraribosomal part of the nascent chain affect the ongoing translation process. Vibrant and regulated molecular interactions involving the ribosome, mRNA, and nascent polypeptidyl-tRNA are based, at least partly, on their autonomously interacting properties.

Focal Adhesion Induction at the Tip of a Functionalized Nanoelectrode

PubMed Central

Fuentes, Daniela E.; Bae, Chilman; Butler, Peter J.

2012-01-01

Cells dynamically interact with their physical micro-environment through the assembly of nascent focal contacts and focal adhesions. The dynamics and mechanics of these contact points are controlled by transmembrane integrins and an array of intracellular adaptor proteins. In order to study the mechanics and dynamics of focal adhesion assembly, we have developed a technique for the timed induction of a nascent focal adhesion. Bovine aortic endothelial cells were approached at the apical surface by a nanoelectrode whose position was controlled with a resolution of 10s of nanometers using changes in electrode current to monitor distance from the cell surface. Since this probe was functionalized with fibronectin, a focal contact formed at the contact location. Nascent focal adhesion assembly was confirmed using time-lapse confocal fluorescent images of red fluorescent protein (RFP) – tagged talin, an adapter protein that binds to activated integrins. Binding to the cell was verified by noting a lack of change of electrode current upon retraction of the electrode. This study demonstrates that functionalized nanoelectrodes can enable precisely-timed induction and 3-D mechanical manipulation of focal adhesions and the assay of the detailed molecular kinetics of their assembly. PMID:22247742

Traceability of different apple varieties by multivariate analysis of isotope ratio mass spectrometry data.

PubMed

Mimmo, Tanja; Camin, Federica; Bontempo, Luana; Capici, Calogero; Tagliavini, Massimo; Cesco, Stefano; Scampicchio, Matteo

2015-11-15

The awareness of customers of the origin of foods has become an important issue. The growing demand for foods that are healthy, safe and of high quality has increased the need for traceability and clear labelling. Thus, this study investigates the capability of C and N stable isotope ratios to determine the geographical origin of several apple varieties grown in northern Italy. Four apple varieties (Cripps Pink, Gala, Golden Delicious, Granny Smith) have been sampled in orchards located in the Districts of Bolzano, Ferrara, Verona and Udine (northern Italy). Carbon (δ(13) C) and nitrogen (δ(15) N) isotope values of the whole apple fruits and three sub-fractions (peel, pulp and seed) have been determined simultaneously by isotope ratio mass spectrometry. The δ(13) C and δ(15) N values of apples and apple sub-fractions, such as peel, seed and pulp, were significantly affected by the geographical origin and the fruit variety. The four varieties could be distinguished to a certain extent only within each district. A 99% correct identification of the samples according to their origin was, however, achieved by cross validation with the 'leave-one-out' method. This study proves the potential of stable isotopes to discriminate the geographical origin of apples grown in orchards located only a few hundreds of kilometres apart. Stable isotopes were also able to discriminate different apple varieties, although only within small geographical areas. Copyright © 2015 John Wiley & Sons, Ltd.

Age-related accumulation of the advanced glycation endproduct pentosidine in human articular cartilage aggrecan: the use of pentosidine levels as a quantitative measure of protein turnover.

PubMed

Verzijl, N; DeGroot, J; Bank, R A; Bayliss, M T; Bijlsma, J W; Lafeber, F P; Maroudas, A; TeKoppele, J M

2001-11-01

During aging, non-enzymatic glycation results in the formation and accumulation of the advanced glycation endproduct pentosidine in long-lived proteins, such as articular cartilage collagen. In the present study, we investigated whether pentosidine accumulation also occurs in cartilage aggrecan. Furthermore, pentosidine levels in aggrecan subfractions of different residence time were used to explore pentosidine levels as a quantitative measure of aggrecan turnover. In order to compare protein turnover rates, protein residence time was measured as racemization of aspartic acid. As has previously been shown for collagen, pentosidine levels increase with age in cartilage aggrecan. Consistent with the faster turnover of aggrecan compared to collagen, the rate of pentosidine accumulation was threefold lower in aggrecan than in collagen. In the subfractions of aggrecan, pentosidine levels increased with protein residence time. These pentosidine levels were used to estimate the half-life of the globular hyaluronan-binding domain of aggrecan to be 19.5 years. This value is in good agreement with the half-life of 23.5 years that was estimated based on aspartic acid racemization. In aggrecan from osteoarthritic (OA) cartilage, decreased pentosidine levels were found compared with normal cartilage, which reflects increased aggrecan turnover during the OA disease process. In conclusion, we showed that pentosidine accumulates with age in aggrecan and that pentosidine levels can be used as a measure of turnover of long-lived proteins, both during normal aging and during disease.

A Mediterranean-style low-glycemic-load diet increases plasma carotenoids and decreases LDL oxidation in women with metabolic syndrome☆

PubMed Central

Barona, Jacqueline; Jones, Jennifer J.; Kopec, Rachel E.; Comperatore, Michael; Andersen, Catherine; Schwartz, Steven J.; Lerman, Robert H.; Fernandez, Maria Luz

2013-01-01

Thirty-five women with metabolic syndrome and high plasma low-density lipoprotein (LDL) cholesterol (≥100 mg/dl) participated in a dietary intervention consisting of a Mediterranean-style low-glycemic-load diet for 12 weeks. Participants were randomly allocated to consume diet only (n=15) or diet plus a medical food containing soy protein and plant sterols (n=20). Plasma concentrations of carotenoids, lipoprotein subfractions and oxidized LDL (OxLDL) were measured. Independent of treatment, women had a significant increase in plasma lutein (P<.0001) and β-carotene (P<.0001), while plasma lycopene was reduced (P<.05) after 12 weeks. Low-density lipoprotein cholesterol was reduced from 138±35 to 114±33 mg/dl (P<.0001). In addition, decreases were observed in the atherogenic subfractions: large very low-density lipoprotein (P<.05), small LDL (P<.00001) and medium high-density lipoprotein (P<.05). Oxidized LDL was significantly reduced by 12% in both groups (P<.01). Changes in OxLDL were inversely correlated with plasma lutein (r=−.478, P<.0001). The data indicate that women complied with the dietary regimen by increasing fruits and vegetable intake. Decreased consumption of high-glycemic foods frequently co-consumed with lycopene-rich tomato sauce such as pasta and pizza may be responsible for the lowering of this carotenoid in plasma after 12 weeks. These results also suggest that plasma lutein concentrations may protect against oxidative stress by reducing the concentrations of OxLDL. PMID:21775117

Isolation and identification of phenolic antioxidants in black rice bran.

PubMed

Jun, Hyun-Il; Shin, Jae-Wook; Song, Geun-Seoup; Kim, Young-Soo

2015-02-01

Black rice bran contains phenolic compounds of a high antioxidant activity. In this study, the 40% acetone extract of black rice bran was sequentially fractionated to obtain 5 fractions. Out of the 5 fractions, ethyl acetate fraction was subfractionated using the Sephadex LH-20 chromatography. The antioxidant activity of phenolic compounds in the extracts was investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical assay, 2,2-azino-bis-(3-ethylenebenzothiozoline-6-sulfonic acid) (ABTS) radical cation assay, reducing power. The subfraction 2 from ethyl acetate fraction had the highest total phenolic contents (TPC) (816.0 μg/mg) and the lowest EC50 values (47.8 μg/mL for DPPH radical assay, 112.8 μg/mL for ABTS radical cation assay, and 49.2 μg/mL for reducing power). These results were 3.1, 1.3, and 2.6 times lower than those of butylated hydroxytoluene (BHT), respectively. At a concentration of 100 μg/mL, the antioxidant activity and TPC of various extracts was closely correlated, with correlation coefficients (R(2) ) higher than 0.86. The major phenolic acid in subfraction 2 was identified as ferulic acid (178.3 μg/mg) by HPLC and LC-ESI/MS/MS analyses. Our finding identified ferulic acid as a major phenolic compound in black rice bran, and supports the potential use of black rice bran as a natural source of antioxidant. © 2015 Institute of Food Technologists®

Identification of cyanidin glycosides as constituents of freeze-dried black raspberries which inhibit anti-benzo[a]pyrene-7,8-diol-9,10-epoxide induced NFκB and AP-1 activity

PubMed Central

Hecht, Stephen S.; Huang, Chuanshu; Stoner, Gary D.; Li, Jingxia; Kenney, Patrick M. J.; Sturla, Shana J.; Carmella, Steven G.

2010-01-01

Dietary freeze-dried black raspberries inhibit tumor induction by N-nitrosomethylbenzylamine in the rat esophagus, but the constituents responsible for this chemopreventive activity have not been identified. We fractionated freeze-dried black raspberries and used mouse epidermal JB6 Cl 41 cells stably transfected with either a nuclear factor kappa B (NFκB)- or an activator protein 1 (AP-1)-luciferase reporter, and treated with racemic anti-benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE), to assess the inhibitory effects of the fractions. The ethanol and water extracts of the freeze-dried black raspberries had inhibitory activity and these extracts were fractionated by HPLC to give several bioactive fractions. Further HPLC analysis yielded multiple subfractions, some of which inhibited BPDE-induced NFκB activity. Major constituents of the most active subfractions were identified by their spectral properties and in comparison with standards as cyanidin-3-O-glucoside, cyanidin 3-O-(2G-xylosylrutinoside) and cyanidin 3-O-rutinoside. Analysis of freeze-dried black raspberries indicated that these three components comprised ∼3.4% of the material by dry weight. Consistent with these results, standard cyanidin-3-O-glucoside and cyanidin chloride were also good inhibitors of BPDE-induced NFκB activity. The results of this study demonstrate that cyanidin glycosides of freeze-dried black raspberries are bioactive compounds which could account for at least some of the chemopreventive activity observed in animal models. PMID:16522666

The chilean superfruit black-berry Aristotelia chilensis (Elaeocarpaceae), Maqui as mediator in inflammation-associated disorders.

PubMed

Cespedes, Carlos L; Pavon, Natalia; Dominguez, Mariana; Alarcon, Julio; Balbontin, Cristian; Kubo, Isao; El-Hafidi, Mohammed; Avila, Jose G

2017-10-01

The effects of phytochemicals occurred in fractions and extracts of fruits of "Maqui-berry" (Aristotelia chilensis), on the expression of cyclooxygenase-2 (COX-2), inducible-nitric oxide synthases (iNOS) and the production of proinflammatory mediators were investigated in lipopolysaccharide (LPS)-activated murine macrophage RAW-264 cells, as well as their antioxidant activities. The MeOH extract (A), acetone/methanol extract (B), fractions F3, F4, subfractions (SF4-SF6, SF7, SF8-SF10, SF11-SF15, SF16-SF20), quercetin, gallic acid, luteolin, myricetin, mixtures M1, M2 and M3 exhibited potent anti-inflammatory and antioxidant activities. The results indicated that anthocyanins, flavonoids and its mixtures suppressed the LPS induced production of nitric oxide (NO), through the down-regulation of iNOS and COX-2 protein expressions and showed a potent antioxidant activity against SOD, ABTS, TBARS, ORAC, FRAP and DCFH. The inhibition of enzymes and NO production by selected fractions and compounds was dose-dependent with significant effects seen at concentration as low as 1.0-50.0 (ppm) and 5.0-10.0 μM, for samples (extracts, fractions, subfractions and mixtures) and pure compounds, respectively. Thus, the phenolics (anthocyanins, flavonoids, and organic acids) as the fractions and mixtures may provide a potential therapeutic approach for inflammation associated disorders and therefore might be used as antagonizing agents to ameliorate the effects of oxidative stress. Copyright © 2016 Elsevier Ltd. All rights reserved.

Identification of cyanidin glycosides as constituents of freeze-dried black raspberries which inhibit anti-benzo[a]pyrene-7,8-diol-9,10-epoxide induced NFkappaB and AP-1 activity.

PubMed

Hecht, Stephen S; Huang, Chuanshu; Stoner, Gary D; Li, Jingxia; Kenney, Patrick M J; Sturla, Shana J; Carmella, Steven G

2006-08-01

Dietary freeze-dried black raspberries inhibit tumor induction by N-nitrosomethylbenzylamine in the rat esophagus, but the constituents responsible for this chemopreventive activity have not been identified. We fractionated freeze-dried black raspberries and used mouse epidermal JB6 Cl 41 cells stably transfected with either a nuclear factor kappa B (NFkappaB)- or an activator protein 1 (AP-1)-luciferase reporter, and treated with racemic anti-benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE), to assess the inhibitory effects of the fractions. The ethanol and water extracts of the freeze-dried black raspberries had inhibitory activity and these extracts were fractionated by HPLC to give several bioactive fractions. Further HPLC analysis yielded multiple subfractions, some of which inhibited BPDE-induced NFkappaB activity. Major constituents of the most active subfractions were identified by their spectral properties and in comparison with standards as cyanidin-3-O-glucoside, cyanidin 3-O-(2(G)-xylosylrutinoside) and cyanidin 3-O-rutinoside. Analysis of freeze-dried black raspberries indicated that these three components comprised approximately 3.4% of the material by dry weight. Consistent with these results, standard cyanidin-3-O-glucoside and cyanidin chloride were also good inhibitors of BPDE-induced NFkappaB activity. The results of this study demonstrate that cyanidin glycosides of freeze-dried black raspberries are bioactive compounds which could account for at least some of the chemopreventive activity observed in animal models.

Phytochemical, sub-acute toxicity, and antibacterial evaluation of Cordia sebestena leaf extracts.

PubMed

Osho, Adeleke; Otuechere, Chiagoziem A; Adeosun, Charles B; Oluwagbemi, Tolu; Atolani, Olubunmi

2016-03-01

In Nigeria, Cordia sebestena (Boraginaceae), an understudied medicinal plant, is used in traditional medicine for the treatment of gastrointestinal disorders. In this study, we investigated the chemical composition, antibacterial potential, and sub-acute toxicity of C. sebestena leaves. Ethyl acetate extracts were analyzed using thin layer chromatography (TLC) and Fourier transform infrared (FTIR) spectrophotometry. The antibacterial potential of the extracts was tested against five standard bacteria, namely Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Clinical observations and blood parameters were used to evaluate the possible toxicity of C. sebestena. The TLC profile yielded 39 fractions, which were pooled to nine combined sub-fractions (A-I). The FTIR spectrum of sub-fraction H indicated the presence of aliphatic C-H stretching vibration at 2922 and 2850 cm-1, C=O stretch at 1734 and 1708 cm-1, and C=C stretch of aromatics and aliphatics at 1464 and (shoulder) 1618 cm-1, respectively. The fractions of the C. sebestena ethyl acetate leaf extract showed antibacterial potential across board, but fraction H had the highest antibacterial activity against B. cereus and S. aureus. The study also indicated the relatively low toxicity profile of the ethyl acetate leaf extract of C. sebestena in the liver of rats. The study showed that C. sebestena leaves have strong antibacterial potential and low toxicity, thereby underlying the scientific basis for their folkloric use in the management of microbial infections and its associated complications.

Protecting the proteome: Eukaryotic cotranslational quality control pathways

PubMed Central

2014-01-01

The correct decoding of messenger RNAs (mRNAs) into proteins is an essential cellular task. The translational process is monitored by several quality control (QC) mechanisms that recognize defective translation complexes in which ribosomes are stalled on substrate mRNAs. Stalled translation complexes occur when defects in the mRNA template, the translation machinery, or the nascent polypeptide arrest the ribosome during translation elongation or termination. These QC events promote the disassembly of the stalled translation complex and the recycling and/or degradation of the individual mRNA, ribosomal, and/or nascent polypeptide components, thereby clearing the cell of improper translation products and defective components of the translation machinery. PMID:24535822

On the alignment of cellulose microfibrils by cortical microtubules: a review and a model.

PubMed

Baskin, T I

2001-01-01

The hypothesis that microtubules align microfibrils, termed the alignment hypothesis, states that there is a causal link between the orientation of cortical microtubules and the orientation of nascent microfibrils. I have assessed the generality of this hypothesis by reviewing what is known about the relation between microtubules and microfibrils in a wide group of examples: in algae of the family Characeae, Closterium acerosum, Oocystis solitaria, and certain genera of green coenocytes and in land plant tip-growing cells, xylem, diffusely growing cells, and protoplasts. The salient features about microfibril alignment to emerge are as follows. Cellulose microfibrils can be aligned by cortical microtubules, thus supporting the alignment hypothesis. Alignment of microfibrils can occur independently of microtubules, showing that an alternative to the alignment hypothesis must exist. Microfibril organization is often random, suggesting that self-assembly is insufficient. Microfibril organization differs on different faces of the same cell, suggesting that microfibrils are aligned locally, not with respect to the entire cell. Nascent microfibrils appear to associate tightly with the plasma membrane. To account for these observations, I present a model that posits alignment to be mediated through binding the nascent microfibril. The model, termed templated incorporation, postulates that the nascent microfibril is incorporated into the cell wall by binding to a scaffold that is oriented; further, the scaffold is built and oriented around either already incorporated microfibrils or plasma membrane proteins, or both. The role of cortical microtubules is to bind and orient components of the scaffold at the plasma membrane. In this way, spatial information to align the microfibrils may come from either the cell wall or the cell interior, and microfibril alignment with and without microtubules are subsets of a single mechanism.

Tumor-targeting Salmonella typhimurium A1-R Inhibits Osteosarcoma Angiogenesis in the In Vivo Gelfoam® Assay Visualized by Color-coded Imaging.

PubMed

Kiyuna, Tasuku; Tome, Yasunori; Uehara, Fuminari; Murakami, Takashi; Zhang, Yong; Zhao, Ming; Kanaya, Fuminori; Hoffman, Robert M

2018-01-01

We previously developed a color-coded imaging model that can quantify the length of nascent blood vessels using Gelfoam® implanted in nestin-driven green fluorescent protein (ND-GFP) nude mice. In this model, nascent blood vessels selectively express GFP. We also previously showed that osteosarcoma cells promote angiogenesis in this assay. We have also previously demonstrated the tumor-targeting bacteria Salmonella typhimurium A1-R (S. typhimurium A1-R) can inhibit or regress all tested tumor types in mouse models. The aim of the present study was to determine if S. typhimurium A1-R could inhibit osteosarcoma angiogenesis in the in vivo Gelfoam® color-coded imaging assay. Gelfoam® was implanted subcutaneously in ND-GFP nude mice. Skin flaps were made 7 days after implantation and 143B-RFP human osteosarcoma cells expressing red fluorescent protein (RFP) were injected into the implanted Gelfoam. After establishment of tumors in the Gelfoam®, control-group mice were treated with phosphate buffered saline via tail-vein injection (iv) and the experimental group was treated with S. typhimurium A1-R iv Skin flaps were made at day 7, 14, 21, and 28 after implantation of the Gelfoam® to allow imaging of vascularization in the Gelfoam® using a variable-magnification small-animal imaging system and confocal fluorescence microscopy. Nascent blood vessels expressing ND-GFP extended into the Gelfoam® over time in both groups. However, the extent of nascent blood-vessel growth was significantly inhibited by S. typhimurium A1-R treatment by day 28. The present results indicate S. typhimurium A1-R has potential for anti-angiogenic targeted therapy of osteosarcoma. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Mouse Mix gene is activated early during differentiation of ES and F9 stem cells and induces endoderm in frog embryos.

PubMed

Mohn, Deanna; Chen, Siming W; Dias, Dora Campos; Weinstein, Daniel C; Dyer, Michael A; Sahr, Kenneth; Ducker, Charles E; Zahradka, Elizabeth; Keller, Gordon; Zaret, Kenneth S; Gudas, Lorraine J; Baron, Margaret H

2003-03-01

In frog and zebrafish, the Mix/Bix family of paired type homeodomain proteins play key roles in specification and differentiation of mesendoderm. However, in mouse, only a single Mix gene (mMix) has been identified to date and its function is unknown. We have analyzed the expression of mouse Mix RNA and protein in embryos, embryoid bodies formed from embryonic stem cells and F9 teratocarcinoma cells, as well as several differentiated cell types. Expression in embryoid bodies in culture mirrors that in embryos, where Mix is transcribed transiently in primitive (visceral) endoderm (VE) and in nascent mesoderm. In F9 cells induced by retinoic acid to differentiate to VE, mMix is coordinately expressed with three other endodermal transcription factors, well before AFP, and its protein product is localized to the nucleus. In a subpopulation of nascent mesodermal cells from embryonic stem cell embryoid bodies, mMix is coexpressed with Brachyury. Intriguingly, mMix mRNA is detected in a population (T+Flk1+) of cells which may contain hemangioblasts, before the onset of hematopoiesis and activation of hematopoietic markers. In vitro and in vivo, mMix expression in nascent mesoderm is rapidly down-regulated and becomes undetectable in differentiated cell types. In the region of the developing gut, mMix expression is confined to the mesoderm of mid- and hindgut but is absent from definitive endoderm. Injection of mouse mMix RNA into early frog embryos results in axial truncation of developing tadpoles and, in animal cap assays, mMix alone is sufficient to activate expression of several endodermal (but not mesodermal) markers. Although these observations do not exclude a possible cell-autonomous function for mMix in mesendodermal progenitor cells, they do suggest an additional, non-cell autonomous role in nascent mesoderm in the formation and/or patterning of adjacent definitive endoderm. Copyright 2003 Wiley-Liss, Inc.

Mammalian DNA enriched for replication origins is enriched for snap-back sequences.

PubMed

Zannis-Hadjopoulos, M; Kaufmann, G; Martin, R G

1984-11-15

Using the instability of replication loops as a method for the isolation of double-stranded nascent DNA, extruded DNA enriched for replication origins was obtained and denatured. Snap-back DNA, single-stranded DNA with inverted repeats (palindromic sequences), reassociates rapidly into stem-loop structures with zero-order kinetics when conditions are changed from denaturing to renaturing, and can be assayed by chromatography on hydroxyapatite. Origin-enriched nascent DNA strands from mouse, rat and monkey cells growing either synchronously or asynchronously were purified and assayed for the presence of snap-back sequences. The results show that origin-enriched DNA is also enriched for snap-back sequences, implying that some origins for mammalian DNA replication contain or lie near palindromic sequences.

A Supercomplex Spanning the Inner and Outer Membranes Mediates the Biogenesis of β-Barrel Outer Membrane Proteins in Bacteria*

PubMed Central

Wang, Yan; Wang, Rui; Jin, Feng; Liu, Yang; Yu, Jiayu; Fu, Xinmiao; Chang, Zengyi

2016-01-01

β-barrel outer membrane proteins (OMPs) are ubiquitously present in Gram-negative bacteria, mitochondria and chloroplasts, and function in a variety of biological processes. The mechanism by which the hydrophobic nascent β-barrel OMPs are transported through the hydrophilic periplasmic space in bacterial cells remains elusive. Here, mainly via unnatural amino acid-mediated in vivo photo-crosslinking studies, we revealed that the primary periplasmic chaperone SurA interacts with nascent β-barrel OMPs largely via its N-domain but with β-barrel assembly machine protein BamA mainly via its satellite P2 domain, and that the nascent β-barrel OMPs interact with SurA via their N- and C-terminal regions. Additionally, via dual in vivo photo-crosslinking, we demonstrated the formation of a ternary complex involving β-barrel OMP, SurA, and BamA in cells. More importantly, we found that a supercomplex spanning the inner and outer membranes and involving the BamA, BamB, SurA, PpiD, SecY, SecE, and SecA proteins appears to exist in living cells, as revealed by a combined analyses of sucrose-gradient ultra-centrifugation, Blue native PAGE and mass spectrometry. We propose that this supercomplex integrates the translocation, transportation, and membrane insertion events for β-barrel OMP biogenesis. PMID:27298319

Spatial organization of transcription machinery and its segregation from the replisome in fast-growing bacterial cells

PubMed Central

Cagliero, Cedric; Zhou, Yan Ning; Jin, Ding Jun

2014-01-01

In a fast-growing Escherichia coli cell, most RNA polymerase (RNAP) is allocated to rRNA synthesis forming transcription foci at clusters of rrn operons or bacterial nucleolus, and each of the several nascent nucleoids contains multiple pairs of replication forks. The composition of transcription foci has not been determined. In addition, how the transcription machinery is three-dimensionally organized to promote cell growth in concord with replication machinery in the nucleoid remains essentially unknown. Here, we determine the spatial and functional landscapes of transcription and replication machineries in fast-growing E. coli cells using super-resolution-structured illumination microscopy. Co-images of RNAP and DNA reveal spatial compartmentation and duplication of the transcription foci at the surface of the bacterial chromosome, encompassing multiple nascent nucleoids. Transcription foci cluster with NusA and NusB, which are the rrn anti-termination system and are associated with nascent rRNAs. However, transcription foci tend to separate from SeqA and SSB foci, which track DNA replication forks and/or the replisomes, demonstrating that transcription machinery and replisome are mostly located in different chromosomal territories to maintain harmony between the two major cellular functions in fast-growing cells. Our study suggests that bacterial chromosomes are spatially and functionally organized, analogous to eukaryotes. PMID:25416798

Recent Developments in the Synthesis of Biomacromolecules and their Conjugates by Single Electron Transfer-Living Radical Polymerization.

PubMed

Lligadas, Gerard; Grama, Silvia; Percec, Virgil

2017-04-10

Single electron transfer-living radical polymerization (SET-LRP) represents a robust and versatile tool for the synthesis of vinyl polymers with well-defined topology and chain end functionality. The crucial step in SET-LRP is the disproportionation of the Cu(I)X generated by activation with Cu(0) wire, powder, or nascent Cu(0) generated in situ into nascent, extremely reactive Cu(0) atoms and nanoparticles and Cu(II)X 2 . Nascent Cu(0) activates the initiator and dormant chains via a homogeneous or heterogeneous outer-sphere single-electron transfer mechanism (SET-LRP). SET-LRP provides an ultrafast polymerization of a plethora of monomers (e.g., (meth)-acrylates, (meth)-acrylamides, styrene, and vinyl chloride) including hydrophobic and water insoluble to hydrophilic and water soluble. Some advantageous features of SET-LRP are (i) the use of Cu(0) wire or powder as readily available catalysts under mild reaction conditions, (ii) their excellent control over molecular weight evolution and distribution as well as polymer chain ends, (iii) their high functional group tolerance allowing the polymerization of commercial-grade monomers, and (iv) the limited purification required for the resulting polymers. In this Perspective, we highlight the recent advancements of SET-LRP in the synthesis of biomacromolecules and of their conjugates.

Cotranslocational degradation: utilitarianism in the ER stress response.

PubMed

Pearse, Bradley R; Hebert, Daniel N

2006-09-15

Recently, a new layer of the unfolded protein response was discovered that supports the cotranslocational degradation of nascent chains stalled in endoplasmic reticulum translocons (Oyadomari et al., 2006).

Small dense HDLs display potent vasorelaxing activity, reflecting their elevated content of sphingosine-1-phosphate.

PubMed

Perségol, Laurence; Darabi, Maryam; Dauteuille, Carolane; Lhomme, Marie; Chantepie, Sandrine; Rye, Kerry-Anne; Therond, Patrice; Chapman, M John; Salvayre, Robert; Nègre-Salvayre, Anne; Lesnik, Philippe; Monier, Serge; Kontush, Anatol

2018-01-01

The functional heterogeneity of HDL is attributed to its diverse bioactive components. We evaluated whether the vasodilatory effects of HDL differed across HDL subpopulations, reflecting their distinct molecular composition. The capacity of five major HDL subfractions to counteract the inhibitory effects of oxidized LDL on acetylcholine-induced vasodilation was tested in a rabbit aortic rings model. NO production, an essential pathway in endothelium-dependent vasorelaxation, was studied in simian vacuolating virus 40-transformed murine endothelial cells (SVECs). Small dense HDL3 subfractions displayed potent vasorelaxing activity (up to +31% vs. baseline, P < 0.05); in contrast, large light HDL2 did not induce aortic-ring relaxation when compared on a total protein basis. HDL3 particles were enriched with sphingosine-1-phosphate (S1P) (up to 3-fold vs. HDL2), with the highest content in HDL3b and -3c that concomitantly revealed the strongest vasorelaxing properties. NO generation was enhanced by HDL3c in SVECs (1.5-fold, P < 0.01), a phenomenon that was blocked by the S1P receptor antagonist, VPC 23019. S1P-enriched reconstituted HDL (rHDL) was a 1.8-fold ( P < 0.01) more potent vasorelaxant than control rHDL in aortic rings. Small dense HDL3 particles displayed potent protective effects against oxidative stress-associated endothelium dysfunction, potentially reflecting their elevated content of S1P that might facilitate interaction with S1P receptors and ensuing NO generation. Copyright © 2018 by the American Society for Biochemistry and Molecular Biology, Inc.

Relationship of carbohydrate molecular spectroscopic features in combined feeds to carbohydrate utilization and availability in ruminants

NASA Astrophysics Data System (ADS)

Zhang, Xuewei; Yu, Peiqiang

To date, there is no study on the relationship between carbohydrate (CHO) molecular structures and nutrient availability of combined feeds in ruminants. The objective of this study was to use molecular spectroscopy to reveal the relationship between CHO molecular spectral profiles (in terms of functional groups (biomolecular, biopolymer) spectral peak area and height intensity) and CHO chemical profiles, CHO subfractions, energy values, and CHO rumen degradation kinetics of combined feeds of hulless barley with pure wheat dried distillers grains with solubles (DDGS) at five different combination ratios (hulless barley to pure wheat DDGS: 100:0, 75:25, 50:50, 25:75, 0:100). The molecular spectroscopic parameters assessed included: lignin biopolymer molecular spectra profile (peak area and height, region and baseline: ca. 1539-1504 cm-1); structural carbohydrate (STCHO, peaks area region and baseline: ca. 1485-1186 cm-1) mainly associated with hemi- and cellulosic compounds; cellulosic materials peak area (centered at ca. 1240 cm-1 with region and baseline: ca. 1272-1186 cm-1); total carbohydrate (CHO, peaks area region and baseline: ca. 1186-946 cm-1). The results showed that the functional groups (biomolecular, biopolymer) in the combined feeds are sensitive to the changes of carbohydrate chemical and nutrient profiles. The changes of the CHO molecular spectroscopic features in the combined feeds were highly correlated with CHO chemical profiles, CHO subfractions, in situ CHO rumen degradation kinetics and fermentable organic matter supply. Further study is needed to investigate possibility of using CHO molecular spectral features as a predictor to estimate nutrient availability in combined feeds for animals and quantify their relationship.

Bioassay-guided isolation of wound healing active compounds from Echium species growing in Turkey.

PubMed

Eruygur, Nuraniye; Yılmaz, Gülderen; Kutsal, Osman; Yücel, Gözde; Üstün, Osman

2016-06-05

The roots and root barks of Echium sp. have been used to treat ulcers, burns and wounds in traditional Turkish medicine. On the basis of them traditional use and literature references, four Echium species were selected for evaluation of them wound healing potential. Isolation of active component(s) from the active extracts through the bioassay guided fractionation procedures. In vivo the wound healing activity of the plants was evaluated by linear incision experimental models. The chloroform extract of Echium italicum L. was fractionated by successive chromatographic techniques. Wound healing activity of each fraction was investigated following the bioassay-guided fractionation procedures. Moreover, the tissue samples of isolated compounds were examined histopathologically. The healing potential was comparatively assessed with a reference ointment Madecassol®, which contains 1% extract of Centella asiatica. Significant wound healing activity was observed from the ointment prepared with ethanol extract at 1% concentration. The ethanol root extract treated in groups of animals showed a significant increase (37.38%, 40.97% and 35.29% separately for E. italicum L, Echium vulgare L. and Echium angustifolium Miller) wound tensile strength in the incision wound model. Subfractions showed significant but reduced wound healing activity on in vivo wound models. Shikonin derivatives "Acetylshikonin", "Deoxyshikonin" and "2-methyl-n-butyrylshikonin+Isovalerylshikonin", were isolated and determined as active components of active final subfraction from E. italicum L. roots. The results of histopathological examination supported the outcome of linear incision wound models. The experimental study revealed that Echium species display remarkable wound healing activity. Copyright © 2016. Published by Elsevier Ireland Ltd.

The influence of temperature calibration on the OC-EC results from a dual-optics thermal carbon analyzer

NASA Astrophysics Data System (ADS)

Pavlovic, J.; Kinsey, J. S.; Hays, M. D.

2014-09-01

Thermal-optical analysis (TOA) is a widely used technique that fractionates carbonaceous aerosol particles into organic and elemental carbon (OC and EC), or carbonate. Thermal sub-fractions of evolved OC and EC are also used for source identification and apportionment; thus, oven temperature accuracy during TOA analysis is essential. Evidence now indicates that the "actual" sample (filter) temperature and the temperature measured by the built-in oven thermocouple (or set-point temperature) can differ by as much as 50 °C. This difference can affect the OC-EC split point selection and consequently the OC and EC fraction and sub-fraction concentrations being reported, depending on the sample composition and in-use TOA method and instrument. The present study systematically investigates the influence of an oven temperature calibration procedure for TOA. A dual-optical carbon analyzer that simultaneously measures transmission and reflectance (TOT and TOR) is used, functioning under the conditions of both the National Institute of Occupational Safety and Health Method 5040 (NIOSH) and Interagency Monitoring of Protected Visual Environment (IMPROVE) protocols. The application of the oven calibration procedure to our dual-optics instrument significantly changed NIOSH 5040 carbon fractions (OC and EC) and the IMPROVE OC fraction. In addition, the well-known OC-EC split difference between NIOSH and IMPROVE methods is even further perturbed following the instrument calibration. Further study is needed to determine if the widespread application of this oven temperature calibration procedure will indeed improve accuracy and our ability to compare among carbonaceous aerosol studies that use TOA.

Paralytic shellfish toxins in phytoplankton and shellfish samples collected from the Bohai Sea, China.

PubMed

Liu, Yang; Yu, Ren-Cheng; Kong, Fan-Zhou; Chen, Zhen-Fan; Dai, Li; Gao, Yan; Zhang, Qing-Chun; Wang, Yun-Feng; Yan, Tian; Zhou, Ming-Jiang

2017-02-15

Phytoplankton and shellfish samples collected periodically from 5 representative mariculture zones around the Bohai Sea, Laishan (LS), Laizhou (LZ), Hangu (HG), Qinhuangdao (QHD) and Huludao (HLD), were analysed for paralytic shellfish toxins (PSTs) using an high-performance liquid chromatography (HPLC) method. Toxins were detected in 13 out of 20 phytoplankton samples, and N-sulfocarbamoyl toxins (C1/2) were predominant components of PSTs in phytoplankton samples with relatively low toxin content. However, two phytoplankton samples with high PST content collected from QHD and LS had unique toxin profiles characterized by high-potency carbamoyl toxins (GTX1/4) and decarbamoyl toxins (dcGTX2/3 and dcSTX), respectively. PSTs were commonly found in shellfish samples, and toxin content ranged from 0 to 27.6nmol/g. High level of PSTs were often found in scallops and clams. Shellfish from QHD in spring, and LZ and LS in autumn exhibited high risks of PST contamination. Copyright © 2016 Elsevier Ltd. All rights reserved.

ESR modes in a Strong-Leg Ladder in the Tomonaga-Luttinger Liquid Phase

NASA Astrophysics Data System (ADS)

Zvyagin, S.; Ozerov, M.; Maksymenko, M.; Wosnitza, J.; Honecker, A.; Landee, C. P.; Turnbull, M.; Furuya, S. C.; Giamarchi, T.

Magnetic excitations in the strong-leg quantum spin ladder compound (C7H10N)2CuBr4 (known as DIMPY) in the field-induced Tomonaga-Luttinger spin liquid phase are studied by means of high-field electron spin resonance (ESR) spectroscopy. The presence of a gapped ESR mode with unusual non-linear frequency-field dependence is revealed experimentally. Using a combination of analytic and exact diagonalization methods, we compute the dynamical structure factor and identify this mode with longitudinal excitations in the antisymmetric channel. We argue that these excitations constitute a fingerprint of the spin dynamics in a strong-leg spin-1/2 Heisenberg antiferromagnetic ladder and owe its ESR observability to the uniform Dzyaloshinskii-Moriya interaction. This work was partially supported by the DFG and Helmholtz Gemeinschaft (Germany), Swiss SNF under Division II, and ERC synergy UQUAM project. We acknowledge the support of the HLD at HZDR, member of the European Magnetic Field Laboratory (EMFL).

Unpacking MOOC Scholarly Discourse: A Review of Nascent MOOC Scholarship

ERIC Educational Resources Information Center

Ebben, Maureen; Murphy, Julien S.

2014-01-01

The rapid rise of MOOCs (Massive Open Online Courses) signals a shift in the ways in which digital teaching and learning are engaged in and understood. Drawing upon a comprehensive search of nine leading academic databases, this paper examines the initial phase of MOOC scholarship (2009-2013), and offers an analysis of these empirical studies that…

75 FR 63037 - General Pulaski Memorial Day, 2010

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-13

... resist subjugation. During his subsequent exile to France, he learned of our nascent struggle for... solemn obligations to each other's security and our shared values, including a deep and abiding...

Effects of exchanging carbohydrate or monounsaturated fat with saturated fat on inflammatory and thrombogenic responses in subjects with abdominal obesity: A randomized controlled trial.

PubMed

Teng, Kim-Tiu; Chang, Lin Faun; Vethakkan, Shireene Ratna; Nesaretnam, Kalanithi; Sanders, Tom A B

2017-10-01

Modification of the amount and type of dietary fat has diverse effects on cardiovascular risk. We recruited 54 abdominally obese subjects to participate in a prospective cross-over design, single-blind trial comparing isocaloric 2000 kcal MUFA or carbohydrate-enriched diet with SFA-enriched diet (control). The control diet consisted of 15E% protein, 53E% carbohydrate and 32E% fat (12E% SFA, 13E% MUFA). A total of ∼7E% of MUFA or refined carbohydrate was exchanged with SFA in the MUFA-rich and carbohydrate-rich diets respectively for 6-weeks. Blood samples were collected at fasting upon trial commencement and at week-5 and 6 of each dietary-intervention phase to measure levels of cytokines (IL-6, IL-1β), C-reactive protein (CRP), thrombogenic markers (E-selectin, PAI-1, D-dimer) and lipid subfractions. Radial pulse wave analysis and a 6-h postprandial mixed meal challenge were carried out at week-6 of each dietary intervention. Blood samples were collected at fasting, 15 and 30 min and hourly intervals thereafter till 6 h after a mixed meal challenge (muffin and milkshake) with SFA or MUFA (872.5 kcal, 50 g fat, 88 g carbohydrates) or CARB (881.3 kcal, 20 g fat, 158 g carbohydrates)- enrichment corresponding to the background diets. No significant differences in fasting inflammatory and thrombogenic factors were noted between diets (P > 0.05). CARB meal was found to increase plasma IL-6 whereas MUFA meal elevated plasma D-dimer postprandially compared with SAFA meal (P < 0.05). Comparing the 3 meals, there were similar postprandial elevations in IL-6 and D-dimer and postprandial reductions in PAI-1, augmentation index and pressure (time effect: P < 0.05). CARB diet was found to reduce HDL 3 by 7.8% and increase small dense HDL (sdHDL) by 8.6% compared with SFA diet (P < 0.05). SFA diet increased large HDL subfractions compared with both CARB and MUFA diets by 4.9% and 6.6% (P < 0.05), respectively. Overall, the evidence presented in this study

Cytotoxic effect of Alpinia scabra (Blume) Náves extracts on human breast and ovarian cancer cells

PubMed Central

2013-01-01

Background Alpinia scabra, locally known as 'Lengkuas raya’, is an aromatic, perennial and rhizomatous herb from the family Zingiberaceae. It is a wild species which grows largely on mountains at moderate elevations in Peninsular Malaysia, but it can also survive in the lowlands like in the states of Terengganu and Northern Johor. The present study reports the cytotoxic potential of A. scabra extracts from different parts of the plant. Methods The experimental approach in the present study was based on a bioassay-guided fractionation. The crude methanol and fractionated extracts (hexane, chloroform and water) from different parts of A. scabra (leaves, rhizomes, roots and pseudo stems) were prepared prior to the cytotoxicity evaluation against human ovarian (SKOV-3) and hormone-dependent breast (MCF7) carcinoma cells. The identified cytotoxic extracts were then subjected to chemical investigations in order to identify the active ingredients. A normal human lung fibroblast cell line (MRC-5) was used to determine the specificity for cancerous cells. The cytotoxic extracts and fractions were also subjected to morphological assessment, DNA fragmentation analysis and DAPI nuclear staining. Results The leaf (hexane and chloroform) and rhizome (chloroform) extracts showed high inhibitory effect against the tested cells. Ten fractions (LC1-LC10) were yielded after purification of the leaf chloroform extract. Fraction LC4 which showed excellent cytotoxic activity was further purified and resulted in 17 sub-fractions (VLC1-VLC17). Sub-fraction VLC9 showed excellent cytotoxicity against MCF7 and SKOV-3 cells but not toxic against normal MRC-5 cells. Meanwhile, eighteen fractions (RC1-RC18) were obtained after purification of the rhizome chloroform extract, of which fraction RC5 showed cytotoxicity against SKOV-3 cells with high selectivity index. There were marked morphological changes when observed using phase-contrast inverted microscope, DAPI nuclear staining and also DNA

Subliminal (latent) processing of pain and its evolution to conscious awareness

PubMed Central

Borsook, David; Youssef, Andrew M.; Barakat, Nadia; Sieberg, Christine B.; Elman, Igor

2018-01-01

By unconscious or covert processing of pain we refer to nascent interactions that affect the eventual deliverance of pain awareness. Thus, internal processes (viz., repeated nociceptive events, inflammatory kindling, re-organization of brain networks, genetic) or external processes (viz., environment, socioeconomic levels, modulation of epigenetic status) contribute to enhancing or inhibiting the presentation of pain awareness. Here we put forward the notion that for many patients, ongoing sub-conscious changes in brain function are significant players in the eventual manifestation of chronic pain. In this review, we provide clinical examples of nascent or what we term pre-pain processes and the neurobiological mechanisms of how these changes may contribute to pain, but also potential opportunities to define the process for early therapeutic interventions. PMID:29476771

Emerging technologies for biotherapeutic bioanalysis from a high-throughput and multiplexing perspective: insights from an AAPS emerging technology action program committee.

PubMed

Purushothama, Shobha; Dysinger, Mark; Chen, Yao; Österlund, Karolina; Mora, Johanna; Chunyk, Allison Given; Peloquin, Russ

2018-02-01

This manuscript aims to provide insights and updates on emerging technologies from a throughput and multiplexing perspective and to update readers on changes in previously reported technologies. The technologies discussed range from nascent (ultrasensitive Cira, Intellicyt ® , Dynaxi and Captsure™) to the more established (Ella and SQIDlite™). For the nascent technologies, there was an emphasis on user interviews and reviews, where available, to help provide an unbiased view to our readers. For the Ella, a review of published user data as well as author and other user experiences are summarized. Due to their emergent nature, all the technologies described are applicable in the early drug development stage, may require an upfront investment of capital and may not perform as expected.

A Supercomplex Spanning the Inner and Outer Membranes Mediates the Biogenesis of β-Barrel Outer Membrane Proteins in Bacteria.

PubMed

Wang, Yan; Wang, Rui; Jin, Feng; Liu, Yang; Yu, Jiayu; Fu, Xinmiao; Chang, Zengyi

2016-08-05

β-barrel outer membrane proteins (OMPs) are ubiquitously present in Gram-negative bacteria, mitochondria and chloroplasts, and function in a variety of biological processes. The mechanism by which the hydrophobic nascent β-barrel OMPs are transported through the hydrophilic periplasmic space in bacterial cells remains elusive. Here, mainly via unnatural amino acid-mediated in vivo photo-crosslinking studies, we revealed that the primary periplasmic chaperone SurA interacts with nascent β-barrel OMPs largely via its N-domain but with β-barrel assembly machine protein BamA mainly via its satellite P2 domain, and that the nascent β-barrel OMPs interact with SurA via their N- and C-terminal regions. Additionally, via dual in vivo photo-crosslinking, we demonstrated the formation of a ternary complex involving β-barrel OMP, SurA, and BamA in cells. More importantly, we found that a supercomplex spanning the inner and outer membranes and involving the BamA, BamB, SurA, PpiD, SecY, SecE, and SecA proteins appears to exist in living cells, as revealed by a combined analyses of sucrose-gradient ultra-centrifugation, Blue native PAGE and mass spectrometry. We propose that this supercomplex integrates the translocation, transportation, and membrane insertion events for β-barrel OMP biogenesis. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Protein folding on the ribosome studied using NMR spectroscopy

PubMed Central

Waudby, Christopher A.; Launay, Hélène; Cabrita, Lisa D.; Christodoulou, John

2013-01-01

NMR spectroscopy is a powerful tool for the investigation of protein folding and misfolding, providing a characterization of molecular structure, dynamics and exchange processes, across a very wide range of timescales and with near atomic resolution. In recent years NMR methods have also been developed to study protein folding as it might occur within the cell, in a de novo manner, by observing the folding of nascent polypeptides in the process of emerging from the ribosome during synthesis. Despite the 2.3 MDa molecular weight of the bacterial 70S ribosome, many nascent polypeptides, and some ribosomal proteins, have sufficient local flexibility that sharp resonances may be observed in solution-state NMR spectra. In providing information on dynamic regions of the structure, NMR spectroscopy is therefore highly complementary to alternative methods such as X-ray crystallography and cryo-electron microscopy, which have successfully characterized the rigid core of the ribosome particle. However, the low working concentrations and limited sample stability associated with ribosome–nascent chain complexes means that such studies still present significant technical challenges to the NMR spectroscopist. This review will discuss the progress that has been made in this area, surveying all NMR studies that have been published to date, and with a particular focus on strategies for improving experimental sensitivity. PMID:24083462

Nucleolin is a nuclear target of heparan sulfate derived from glypican-1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheng, Fang; Belting, Mattias; Fransson, Lars-Åke

The recycling, S-nitrosylated heparan sulfate (HS) proteoglycan glypican-1 releases anhydromannose (anMan)-containing HS chains by a nitrosothiol-catalyzed cleavage in endosomes that can be constitutive or induced by ascorbate. The HS-anMan chains are then transported to the nucleus. A specific nuclear target for HS-anMan has not been identified. We have monitored endosome-to-nucleus trafficking of HS-anMan by deconvolution and confocal immunofluorescence microscopy using an anMan-specific monoclonal antibody in non-growing, ascorbate-treated, and growing, untreated, wild-type mouse embryonic fibroblasts and hypoxia-exposed Alzheimer mouse Tg2576 fibroblasts and human U87 glioblastoma cells. In all cells, nuclear HS-anMan targeted a limited number of sites of variable size wheremore » it colocalized with DNA and nucleolin, an established marker for nucleoli. HS-anMan also colocalized with ethynyl uridine-tagged nascent RNA and two acetylated forms of histone H3. Acute hypoxia increased the formation of HS-anMan in both Tg2576 and U87 cells. A portion of HS-anMan colocalized with nucleolin at small discrete sites, while most of the nucleolin and nascent RNA was dispersed. In U87 cells, HS-anMan, nucleolin and nascent RNA reassembled after prolonged hypoxia. Nucleolar HS may modulate synthesis and/or release of rRNA.« less

Coordinated international action to accelerate genome-to-phenome with FAANG, The Functional Annotation of Animal Genomes project

USDA-ARS?s Scientific Manuscript database

We describe the organization of a nascent international effort - the "Functional Annotation of ANimal Genomes" project - whose aim is to produce comprehensive maps of functional elements in the genomes of domesticated animal species....

Structure, dynamics and folding of an immunoglobulin domain of the gelation factor (ABP-120) from Dictyostelium discoideum.

PubMed

Hsu, Shang-Te Danny; Cabrita, Lisa D; Fucini, Paola; Dobson, Christopher M; Christodoulou, John

2009-05-15

We have carried out a detailed structural and dynamical characterisation of the isolated fifth repeat of the gelation factor (ABP-120) from Dictyostelium discoideum (ddFLN5) by NMR spectroscopy to provide a basis for studies of co-translational folding on the ribosome of this immunoglobulin-like domain. The isolated ddFLN5 can fold autonomously in solution into a structure that resembles very closely the crystal structure of the domain in a construct in which the adjacent sixth repeat (ddFLN6) is covalently linked to its C-terminus in tandem but deviates locally from a second crystal structure in which ddFLN5 is flanked by ddFLN4 and ddFLN6 at both N- and C-termini. Conformational fluctuations were observed via (15)N relaxation methods and are primarily localised in the interstrand loops that encompass the C-terminal hemisphere. These fluctuations are distinct in location from the region where line broadening is observed in ddFLN5 when attached to the ribosome as part of a nascent chain. This observation supports the conclusion that the broadening is associated with interactions with the ribosome surface [Hsu, S. T. D., Fucini, P., Cabrita, L. D., Launay, H., Dobson, C. M. & Christodoulou, J. (2007). Structure and dynamics of a ribosome-bound nascent chain by NMR spectroscopy. Proc. Natl. Acad. Sci. USA, 104, 16516-16521]. The unfolding of ddFLN5 induced by high concentrations of urea shows a low population of a folding intermediate, as inferred from an intensity-based analysis, a finding that differs from that of ddFLN5 as a ribosome-bound nascent chain. These results suggest that interesting differences in detail may exist between the structure of the domain in isolation and when linked to the ribosome and between protein folding in vitro and the folding of a nascent chain as it emerges from the ribosome.

Healthcare- and Community-Associated Methicillin-Resistant Staphylococcus aureus (MRSA) and Fatal Pneumonia with Pediatric Deaths in Krasnoyarsk, Siberian Russia: Unique MRSA's Multiple Virulence Factors, Genome, and Stepwise Evolution

PubMed Central

Khokhlova, Olga E.; Hung, Wei-Chun; Wan, Tsai-Wen; Iwao, Yasuhisa; Takano, Tomomi; Higuchi, Wataru; Yachenko, Svetlana V.; Teplyakova, Olga V.; Kamshilova, Vera V.; Kotlovsky, Yuri V.; Nishiyama, Akihito; Reva, Ivan V.; Sidorenko, Sergey V.; Peryanova, Olga V.; Reva, Galina V.; Teng, Lee-Jene; Salmina, Alla B.; Yamamoto, Tatsuo

2015-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) is a common multidrug-resistant (MDR) pathogen. We herein discussed MRSA and its infections in Krasnoyarsk, Siberian Russia between 2007 and 2011. The incidence of MRSA in 3,662 subjects was 22.0% and 2.9% for healthcare- and community-associated MRSA (HA- and CA-MRSA), respectively. The 15-day mortality rates for MRSA hospital- and community-acquired pneumonia (HAP and CAP) were 6.5% and 50%, respectively. MRSA CAP cases included pediatric deaths; of the MRSA pneumonia episodes available, ≥27.3% were associated with bacteremia. Most cases of HA-MRSA examined exhibited ST239/spa3(t037)/SCCmecIII.1.1.2 (designated as ST239Kras), while all CA-MRSA cases examined were ST8/spa1(t008)/SCCmecIV.3.1.1(IVc) (designated as ST8Kras). ST239Kras and ST8Kras strongly expressed cytolytic peptide (phenol-soluble modulin α, PSMα; and δ-hemolysin, Hld) genes, similar to CA-MRSA. ST239Kras pneumonia may have been attributed to a unique set of multiple virulence factors (MVFs): toxic shock syndrome toxin-1 (TSST-1), elevated PSMα/Hld expression, α-hemolysin, the staphylococcal enterotoxin SEK/SEQ, the immune evasion factor SCIN/SAK, and collagen adhesin. Regarding ST8Kras, SEA was included in MVFs, some of which were common to ST239Kras. The ST239Kras (strain OC3) genome contained: a completely unique phage, φSa7-like (W), with no att repetition; S. aureus pathogenicity island SaPI2R, the first TSST-1 gene-positive (tst +) SaPI in the ST239 lineage; and a super copy of IS256 (≥22 copies/genome). ST239Kras carried the Brazilian SCCmecIII.1.1.2 and United Kingdom-type tst. ST239Kras and ST8Kras were MDR, with the same levofloxacin resistance mutations; small, but transmissible chloramphenicol resistance plasmids spread widely enough to not be ignored. These results suggest that novel MDR and MVF+ HA- and CA-MRSA (ST239Kras and ST8Kras) emerged in Siberian Russia (Krasnoyarsk) associated with fatal pneumonia, and also with ST

Liquid disinfecting and sterilization reprocessors used for flexible endoscopes.

PubMed

1994-06-01

In this issue, we evaluate three liquid disinfecting flexible endoscope reprocessors that can be used with a user-supplied liquid chemical germicide (LCG), primarily for high-level disinfection (HLD). Applying most of the same criteria and test methods, we also evaluated a fourth unit, presented separately, that is marketed as a liquid sterilizing reprocessor and must be used with manufacturer-supplied, single-use containers of LCG. Although the sterilizing unit can be used for rigid endoscopes, surgical instruments, and endoscopic accessories, we evaluated its application to the reprocessing of only flexible endoscopes. Our ratings are based on the following: (1) basic performance, such as compatibility with several different types of endoscopes and LCGs, inclusion of all essential reprocessing phases, and exposure of all endoscope surfaces to the LCG and rinse water; (2) safety, such as ensuring that essential reprocessing phases cannot be skipped or omitted, that personnel exposure to LCG vapors is minimized, and that the reprocessor is unlikely to contaminate the endoscope during reprocessing; and (3) human factors design, such as ease of use and installation. We did not perform microbiological testing to confirm HLD or sterilization by any of the evaluated reprocessors because, with a suitably clean endoscope that is in good condition, no evidence indicates that the LCGs used would not be effective on the surfaces that they contact; also, the results would be unique to the two flexible endoscopes that we used for our testing. We rated all four reprocessors Conditionally Acceptable. The units are Acceptable on the condition that users understand that they cannot be used to process the elevator cable channel of side-viewing duodenoscopes; additional conditions apply only to the liquid disinfecting units. However, if the conditions are met, all four units reduce the likelihood of using a contaminated endoscope on a patient and reduce personnel exposure to the LCG

Coordinated international action to accelerate genome-to-phenome with FAANG, the Functional Annotation of Animal Genomes project.

PubMed

Andersson, Leif; Archibald, Alan L; Bottema, Cynthia D; Brauning, Rudiger; Burgess, Shane C; Burt, Dave W; Casas, Eduardo; Cheng, Hans H; Clarke, Laura; Couldrey, Christine; Dalrymple, Brian P; Elsik, Christine G; Foissac, Sylvain; Giuffra, Elisabetta; Groenen, Martien A; Hayes, Ben J; Huang, LuSheng S; Khatib, Hassan; Kijas, James W; Kim, Heebal; Lunney, Joan K; McCarthy, Fiona M; McEwan, John C; Moore, Stephen; Nanduri, Bindu; Notredame, Cedric; Palti, Yniv; Plastow, Graham S; Reecy, James M; Rohrer, Gary A; Sarropoulou, Elena; Schmidt, Carl J; Silverstein, Jeffrey; Tellam, Ross L; Tixier-Boichard, Michele; Tosser-Klopp, Gwenola; Tuggle, Christopher K; Vilkki, Johanna; White, Stephen N; Zhao, Shuhong; Zhou, Huaijun

2015-03-25

We describe the organization of a nascent international effort, the Functional Annotation of Animal Genomes (FAANG) project, whose aim is to produce comprehensive maps of functional elements in the genomes of domesticated animal species.

DOE Office of Scientific and Technical Information (OSTI.GOV)

FLANAGAN,J.M.; BEWLEY,M.C.

It is generally accepted that the information necessary to specify the native, functional, three-dimensional structure of a protein is encoded entirely within its amino acid sequence; however, efficient reversible folding and unfolding is observed only with a subset of small single-domain proteins. Refolding experiments often lead to the formation of kinetically-trapped, misfolded species that aggregate, even in dilute solution. In the cellular environment, the barriers to efficient protein folding and maintenance of native structure are even larger due to the nature of this process. First, nascent polypeptides must fold in an extremely crowded environment where the concentration of macromolecules approachesmore » 300-400 mg/mL and on average, each ribosome is within its own diameter of another ribosome (1-3). These conditions of severe molecular crowding, coupled with high concentrations of nascent polypeptide chains, favor nonspecific aggregation over productive folding (3). Second, folding of newly-translated polypeptides occurs in the context of their vehtorial synthesis process. Amino acids are added to a growing nascent chain at the rate of -5 residues per set, which means that for a 300 residue protein its N-terminus will be exposed to the cytosol {approx}1 min before its C-terminus and be free to begin the folding process. However, because protein folding is highly cooperative, the nascent polypeptide cannot reach its native state until a complete folding domain (50-250 residues) has emerged from the ribosome. Thus, for a single-domain protein, the final steps in folding are only completed post-translationally since {approx}40 residues of a nascent chain are sequestered within the exit channel of the ribosome and are not available for folding (4). A direct consequence of this limitation in cellular folding is that during translation incomplete domains will exist in partially-folded states that tend to expose hydrophobic residues that are prone to

Hydrophobicity as a driver of MHC class I antigen processing

PubMed Central

Huang, Lan; Kuhls, Matthew C; Eisenlohr, Laurence C

2011-01-01

The forces that drive conversion of nascent protein to major histocompatibility complex (MHC) class I-restricted peptides remain unknown. We explored the fundamental property of overt hydrophobicity as such a driver. Relocation of a membrane glycoprotein to the cytosol via signal sequence ablation resulted in rapid processing of nascent protein not because of the misfolded luminal domain but because of the unembedded transmembrane (TM) domain, which serves as a dose-dependent degradation motif. Dislocation of the TM domain during the natural process of endoplasmic reticulum-associated degradation (ERAD) similarly accelerated peptide production, but in the context of markedly prolonged processing that included nonnascent species. These insights into intracellular proteolytic pathways and their selective contributions to MHC class I-restricted peptide supply, may point to new approaches in rational vaccine design. PMID:21378750

Hydrophobicity as a driver of MHC class I antigen processing.

PubMed

Huang, Lan; Kuhls, Matthew C; Eisenlohr, Laurence C

2011-04-20

The forces that drive conversion of nascent protein to major histocompatibility complex (MHC) class I-restricted peptides remain unknown. We explored the fundamental property of overt hydrophobicity as such a driver. Relocation of a membrane glycoprotein to the cytosol via signal sequence ablation resulted in rapid processing of nascent protein not because of the misfolded luminal domain but because of the unembedded transmembrane (TM) domain, which serves as a dose-dependent degradation motif. Dislocation of the TM domain during the natural process of endoplasmic reticulum-associated degradation (ERAD) similarly accelerated peptide production, but in the context of markedly prolonged processing that included nonnascent species. These insights into intracellular proteolytic pathways and their selective contributions to MHC class I-restricted peptide supply, may point to new approaches in rational vaccine design.

Aerodynamic loads on a Darrieus rotor blade

NASA Astrophysics Data System (ADS)

Wilson, R. E.; McKie, W. R.; Lissaman, P. B. S.; James, M.

1983-03-01

A method is presented for the free vortex analysis of a Darrieus rotor blade in nonsteady motion, which employs the circle theorem to map the moving rotor airfoil into the circle plane and models the wake generated in terms of point vortices. Nascent vortex strength and position are taken from the Kutta condition, so that the nascent vortex has the same strength as a vortex sheet of uniform strength. Pressure integration over the plate and wake vortex impulse methods yields the same numerical results. The numerical results presented for a one-bladed Darrieus rotor at a tip/speed ratio of three, and two different chord sizes, indicate that the moment on the blade can be adequately approximated by quasi-steady relationships, although the accurate determination of local velocity and circulation are still required.

Subliminal (latent) processing of pain and its evolution to conscious awareness.

PubMed

Borsook, David; Youssef, Andrew M; Barakat, Nadia; Sieberg, Christine B; Elman, Igor

2018-05-01

By unconscious or covert processing of pain we refer to nascent interactions that affect the eventual deliverance of pain awareness. Thus, internal processes (viz., repeated nociceptive events, inflammatory kindling, reorganization of brain networks, genetic) or external processes (viz., environment, socioeconomic levels, modulation of epigenetic status) contribute to enhancing or inhibiting the presentation of pain awareness. Here we put forward the notion that for many patients, ongoing sub-conscious changes in brain function are significant players in the eventual manifestation of chronic pain. In this review, we provide clinical examples of nascent or what we term pre-pain processes and the neurobiological mechanisms of how these changes may contribute to pain, but also potential opportunities to define the process for early therapeutic interventions. Copyright © 2018. Published by Elsevier Ltd.

Mechanism of transfer of LDL-derived free cholesterol to HDL subfractions in human plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miida, T.; Fielding, C.J.; Fielding, P.E.

1990-11-01

The transfer of ({sup 3}H)cholesterol in low-density lipoprotein (LDL) to different high-density lipoprotein (HDL) species in native human plasma was determined by using nondenaturing two-dimensional electrophoresis. Transfer from LDL had a t{sub 1/2} at 37{degree}C of 51 {plus minus} 8 min and an activation energy of 18.0 kCal mol{sup {minus}1}. There was unexpected specificity among HDL species as acceptors of LDL-derived labeled cholesterol. The largest fraction of the major {alpha}-migrating class (HDL{sub 2b}) was the major initial acceptor of LDL-derived cholesterol. Kinetic analysis indicated a rapid secondary transfer from HDL{sub 2b} to smaller {alpha}HDL (particularly HDL{sub 3}) driven enzymatically bymore » the lecithin-cholesterol acyltransferase reaction. Rates of transfer among {alpha}HDL were most rapid from the largest {alpha}HDL fraction (HDL{sub 2b}), suggesting possible protein-mediated facilitation. Simultaneous measurements of the transport of LDL-derived and cell-derived isotopic cholesterol indicated that the former preferably utilized the {alpha}HDL pathyway, with little label in pre-{beta}HDL. The same experiments confirmed earlier data that cell-derived cholesterol is preferentially channeled through pre-{beta}HDL. The authors suggest that the functional heterogeneity of HDL demonstrated here includes the ability to independently process cell- and LDL-derived free cholesterol.« less

Piper betel leaf extract: anticancer benefits and bio-guided fractionation to identify active principles for prostate cancer management.

PubMed

Paranjpe, Rutugandha; Gundala, Sushma R; Lakshminarayana, N; Sagwal, Arpana; Asif, Ghazia; Pandey, Anjali; Aneja, Ritu

2013-07-01

Plant extracts, a concoction of bioactive non-nutrient phytochemicals, have long served as the most significant source of new leads for anticancer drug development. Explored for their unique medicinal properties, the leaves of Piper betel, an evergreen perennial vine, are a reservoir of phenolics with antimutagenic, antitumor and antioxidant activities. Here, we show that oral feeding of betel leaf extract (BLE) significantly inhibited the growth of human prostate xenografts implanted in nude mice compared with vehicle-fed controls. To gain insights into the 'active principles', we performed a bioactivity-guided fractionation of methanolic BLE employing solvents of different polarity strengths using classical column chromatography. This approach yielded 15 fractions, which were then pooled to 10 using similar retention factors on thin-layer chromatographs. Bioactivity assays demonstrated that one fraction in particular, F2, displayed a 3-fold better in vitro efficacy to inhibit proliferation of prostate cancer cells than the parent BLE. The presence of phenols, hydroxychavicol (HC) and chavibetol (CHV), was confirmed in F2 by nuclear magnetic resonance, high-performance liquid chromatography and mass spectroscopy. Further, the HC containing F2 subfraction was found to be ~8-fold more potent than the F2 subfraction that contained CHV, in human prostate cancer PC-3 cells as evaluated by the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide assay. Removing CHV from F2 remarkably decreased the IC50 of this fraction, indicating that HC is perhaps the major bioactive constituent, which is present to an extent of 26.59% in BLE. These data provide evidence that HC is a potential candidate for prostate cancer management and warrants further preclinical evaluation.

Beta2-adrenoceptor-mediated tracheal relaxation induced by higenamine from Nandina domestica Thunberg.

PubMed

Tsukiyama, Muneo; Ueki, Takuro; Yasuda, Yoichi; Kikuchi, Hiroko; Akaishi, Tatsuhiro; Okumura, Hidenobu; Abe, Kazuho

2009-10-01

The fruit of Nandina domestica Thunberg (ND, Berberidaceae) has been used to improve cough and breathing difficulties in Japan for many years, but very little is known about the constituent of ND responsible for this effect. We have recently reported that the crude extract from ND (NDE) inhibits histamine- and serotonin-induced contraction of isolated guinea pig trachea, and the inhibitory activity was not explained by nantenine, a well-known alkaloid isolated from ND. To explore other constituent(s) of NDE with tracheal smooth muscle relaxant activity, we fractionated NDE and assessed the pharmacological effects of the fractions using isolated guinea pig tracheal ring preparations. NDE was introduced into a polyaromatic absorbent resin column and stepwise eluted to yield five fractions, among which only the 40 % methanol fraction was active in relaxing tracheal smooth muscle precontracted with histamine. Further separation of the 40 % methanol fraction with high-performance liquid chromatography yielded multiple subfractions, one of which was remarkably active in relaxing histamine-precontracted trachea. Chemical analysis with a time-of-flight mass spectrometer and nuclear magnetic resonance spectrometer identified the constituent of the most active subfraction as higenamine, a benzyltetrahydroisoquinoline alkaloid. The potency and efficacy of the active constituent from NDE in relaxing trachea were almost equivalent to synthetic higenamine. In addition, the effect of the active constituent from NDE was competitively inhibited by the selective beta (2)-adrenoceptor antagonist ICI 118,551. These results indicate that the major constituent responsible for the effect of NDE is higenamine, which probably causes the tracheal relaxation through stimulation of beta (2) adrenoceptors. Georg Thieme Verlag KG Stuttgart-New York.

Using vibrational molecular spectroscopy to reveal association of steam-flaking induced carbohydrates molecular structural changes with grain fractionation, biodigestion and biodegradation

NASA Astrophysics Data System (ADS)

Xu, Ningning; Liu, Jianxin; Yu, Peiqiang

2018-04-01

Advanced vibrational molecular spectroscopy has been developed as a rapid and non-destructive tool to reveal intrinsic molecular structure conformation of biological tissues. However, this technique has not been used to systematically study flaking induced structure changes at a molecular level. The objective of this study was to use vibrational molecular spectroscopy to reveal association between steam flaking induced CHO molecular structural changes in relation to grain CHO fractionation, predicted CHO biodegradation and biodigestion in ruminant system. The Attenuate Total Reflectance Fourier-transform Vibrational Molecular Spectroscopy (ATR-Ft/VMS) at SRP Key Lab of Molecular Structure and Molecular Nutrition, Ministry of Agriculture Strategic Research Chair Program (SRP, University of Saskatchewan) was applied in this study. The fractionation, predicted biodegradation and biodigestion were evaluated using the Cornell Net Carbohydrate Protein System. The results show that: (1) The steam flaking induced significant changes in CHO subfractions, CHO biodegradation and biodigestion in ruminant system. There were significant differences between non-processed (raw) and steam flaked grain corn (P < .01); (2) The ATR-Ft/VMS molecular technique was able to detect the processing induced CHO molecular structure changes; (3) Induced CHO molecular structure spectral features are significantly correlated (P < .05) to CHO subfractions, CHO biodegradation and biodigestion and could be applied to potentially predict CHO biodegradation (R2 = 0.87, RSD = 0.74, P < .01) and intestinal digestible undegraded CHO (R2 = 0.87, RSD = 0.24, P < .01). In summary, the processing induced molecular CHO structure changes in grain corn could be revealed by the ATR-Ft/VMS vibrational molecular spectroscopy. These molecular structure changes in grain were potentially associated with CHO biodegradation and biodigestion.

Glycoprotein Ibα receptor instability is associated with loss of quality in platelets produced in culture.

PubMed

Robert, Amélie; Boyer, Lucie; Pineault, Nicolas

2011-03-01

The development of culture processes for hematopoietic progenitors could lead to the development of a complementary source of platelets for therapeutic purposes. However, functional characterization of culture-derived platelets remains limited, which raises some uncertainties about the quality of platelets produced in vitro. The aim of this study was to define the proportion of functional platelets produced in cord blood CD34+ cell cultures. Toward this, the morphological and functional properties of culture-derived platelet-like particles (PLPs) were critically compared to that of blood platelets. Flow cytometry combined with transmission electron microscopy analyses revealed that PLPs formed a more heterogeneous population of platelets at a different stage of maturation than blood platelets. The majority of PLPs harbored the fibrinogen receptor αIIbβ3, but a significant proportion failed to maintain glycoprotein (GP)Ibα surface expression, a component of the vWF receptor essential for platelet functions. Importantly, GPIbα extracellular expression correlated closely with platelet function, as the GPIIb+ GPIbα+ PLP subfraction responded normally to agonist stimulation as evidenced by α-granule release, adhesion, spreading, and aggregation. In contrast, the GPIIb+ GPIbα⁻ subfraction was unresponsive in most functional assays and appeared to be metabolically inactive. The present study confirms that functional platelets can be generated in cord blood CD34+ cell cultures, though these are highly susceptible to ectodomain shedding of receptors associated with loss of function. Optimization of culture conditions to prevent these deleterious effects and to homogenize PLPs is necessary to improve the quality and yields of culture-derived platelets before they can be recognized as a suitable complementary source for therapeutic purposes.

Wound-healing and antimicrobial properties of dichloromethane fraction of Dialium guineense (Wild) fruit coat.

PubMed

Okeke, Nnadi Charles; Udeani, Theophilus Kc; Onyebuchi, Ugwu Linus

2016-01-01

This research established the scientific bases for the folkloric use of the neglected Dialium guineense fruit coat in wound and microbial infection management in Nigeria. The phytochemical analysis of the crude extract, fractions and sub-fractions was performed by standard methods. Agar well diffusion protocol was adopted for the antimicrobial assay while the wound healing properties was determined by full thickness skin excision wound model. Phytochemical analysis showed high relative proportion of alkaloids (6.05 ± 0.98 %), saponins (3.91 ± 0.02 %) and tannins (1.86 ± 0.05 %). The only active fraction (DF) and sub-fraction (DF-5) were effective against Gram-positive (inhibition zone diameters, IZDs, 8-10 mm and 11-15 mm) and Gram-negative (IZDs, 15-19 mm and 16-21 mm) bacteria and fungi (6-8 mm) compared with 20-24 mm and 18-19 mm of the standard (ciprofloxacin) respectively. Fifty mg/kg of the DF-5 showed nearly equal percentage wound healing post-surgery days to Cicatrin®. The 50 mg/kg dose of DF and DF-5 showed more than 50 % wound healing at 10(th) day post-surgery, 50 mg/kg crude extract showed 54 % on day 14 while distilled water showed 56 % wound healing on day 17 with no sign of infection in all animal groups. All the treatments were significantly (P<0.01) different from control (distilled water) in wound healing by the 10(th) and 17(th) post-surgery days. The studies revealed that the fruit coat, which hitherto was treated as wastes could be explored for antimicrobial and wound healing properties against the backdrop of continually emerging antibiotic resistant strains of microorganisms.

Wound-healing and antimicrobial properties of dichloromethane fraction of Dialium guineense (Wild) fruit coat

PubMed Central

Okeke, Nnadi Charles; Udeani, Theophilus KC; Onyebuchi, Ugwu Linus

2016-01-01

This research established the scientific bases for the folkloric use of the neglected Dialium guineense fruit coat in wound and microbial infection management in Nigeria. The phytochemical analysis of the crude extract, fractions and sub-fractions was performed by standard methods. Agar well diffusion protocol was adopted for the antimicrobial assay while the wound healing properties was determined by full thickness skin excision wound model. Phytochemical analysis showed high relative proportion of alkaloids (6.05 ± 0.98 %), saponins (3.91 ± 0.02 %) and tannins (1.86 ± 0.05 %). The only active fraction (DF) and sub-fraction (DF-5) were effective against Gram-positive (inhibition zone diameters, IZDs, 8-10 mm and 11-15 mm) and Gram-negative (IZDs, 15-19 mm and 16-21 mm) bacteria and fungi (6-8 mm) compared with 20-24 mm and 18-19 mm of the standard (ciprofloxacin) respectively. Fifty mg/kg of the DF-5 showed nearly equal percentage wound healing post-surgery days to Cicatrin®. The 50 mg/kg dose of DF and DF-5 showed more than 50 % wound healing at 10th day post-surgery, 50 mg/kg crude extract showed 54 % on day 14 while distilled water showed 56 % wound healing on day 17 with no sign of infection in all animal groups. All the treatments were significantly (P<0.01) different from control (distilled water) in wound healing by the 10th and 17th post-surgery days. The studies revealed that the fruit coat, which hitherto was treated as wastes could be explored for antimicrobial and wound healing properties against the backdrop of continually emerging antibiotic resistant strains of microorganisms. PMID:27499791

Inhibition of autophagy as a treatment strategy for p53 wild-type acute myeloid leukemia

PubMed Central

Folkerts, Hendrik; Hilgendorf, Susan; Wierenga, Albertus T J; Jaques, Jennifer; Mulder, André B; Coffer, Paul J; Schuringa, Jan Jacob; Vellenga, Edo

2017-01-01

Here we have explored whether inhibition of autophagy can be used as a treatment strategy for acute myeloid leukemia (AML). Steady-state autophagy was measured in leukemic cell lines and primary human CD34+ AML cells with a large variability in basal autophagy between AMLs observed. The autophagy flux was higher in AMLs classified as poor risk, which are frequently associated with TP53 mutations (TP53mut), compared with favorable- and intermediate-risk AMLs. In addition, the higher flux was associated with a higher expression level of several autophagy genes, but was not affected by alterations in p53 expression by knocking down p53 or overexpression of wild-type p53 or p53R273H. AML CD34+ cells were more sensitive to the autophagy inhibitor hydroxychloroquine (HCQ) than normal bone marrow CD34+ cells. Similar, inhibition of autophagy by knockdown of ATG5 or ATG7 triggered apoptosis, which coincided with increased expression of p53. In contrast to wild-type p53 AML (TP53wt), HCQ treatment did not trigger a BAX and PUMA-dependent apoptotic response in AMLs harboring TP53mut. To further characterize autophagy in the leukemic stem cell-enriched cell fraction AML CD34+ cells were separated into ROSlow and ROShigh subfractions. The immature AML CD34+-enriched ROSlow cells maintained higher basal autophagy and showed reduced survival upon HCQ treatment compared with ROShigh cells. Finally, knockdown of ATG5 inhibits in vivo maintenance of AML CD34+ cells in NSG mice. These results indicate that targeting autophagy might provide new therapeutic options for treatment of AML since it affects the immature AML subfraction. PMID:28703806

Exclusive nuclear location of estrogen receptors in Squalus testis.

PubMed Central

Callard, G V; Mak, P

1985-01-01

An estrogen (E)-binding molecule having both occupied and unoccupied sites is restricted to nuclear subfractions in the testis of the spiny dogfish (Squalus acanthias). We investigated the hypothesis that a species characterized by high body-fluid osmolarity (1010 mosM) has an estrogen receptor (ER) that binds to chromatin with high affinity and consequently resists redistribution during tissue processing. Although the steroid binding and sedimentation properties of the Squalus nuclear ER conformed to those of classical ER, its elution maximum from DNA-cellulose was unusually high (0.55 M NaCl). A tendency to adhere tightly to cell nuclei was reflected in the high salt concentration (0.43 M KCl) required to extract 50% of the receptors from the nuclear compartment during homogenization and in the stability of the nuclear ER population in the presence of high concentrations of a nonionic solute (urea) or increased buffer volume. Mixing and redistribution experiments showed that nuclear ER could be quantitatively and qualitatively measured in cytosolic extracts, ruling out the possibility that soluble receptors were being masked. Although Squalus oviduct ER was similar to that of testis, ER in the testis and liver of a related elasmobranch (Potamotrygon) that maintains osmotic equilibrium at 300 mosM more closely resembled mammalian ER in its elution maximum from DNA-cellulose (0.22 M NaCl) and cytosolic/nuclear ratios in low-salt buffers. We conclude that Squalus testis has a single ER pool located exclusively in the nuclear compartment. These observations support a revised concept of steroid action and further indicate that the chromatin affinity of the hormone-ER complex is an important factor in determining subfractional distribution during tissue processing. PMID:3856265

Traditionally used medicinal plants against uncomplicated urinary tract infections: Are unusual, flavan-4-ol- and derhamnosylmaysin derivatives responsible for the antiadhesive activity of extracts obtained from stigmata of Zea mays L. against uropathogenic E. coli and Benzethonium chloride as frequent contaminant faking potential antibacterial activities?

PubMed

Rafsanjany, Nasli; Sendker, Jandirk; Lechtenberg, Matthias; Petereit, Frank; Scharf, Birte; Hensel, Andreas

2015-09-01

The dried stigmata from Zea mays L. are used traditionally for the treatment of uncomplicated urinary tract infections. A recent screening has indicated that hydroalcoholic extract of the herbal material inhibits the adhesion of uropathogenic Escherichia coli (UPEC) to T24 bladder cells. For verification of these data EtOH-water (1:1) extracts from 4 different batches of Maydis stigmata were investigated. Within an in vitro adhesion assay (UPEC strain 2980 and human T24 bladder cells) a dose-dependent antiadhesive activity against UPEC was verified (IC50 1040μg/mL). Bioassay guided fractionation of M. stigmata, batch S1, by EtOH-water extraction, followed by chromatography on Sephadex LH20 revealed two active fractions (I and XI). Further purification of fraction I and structure elucidation of the isolated compound revealed the presence of significant amounts of the biocide benzethonium chloride as contaminant. Benzethonium chloride was also identified in subsequent investigations in 2 different batches of M. stigmata. The presence of such nondeclared and illegal contaminants in the herbal raw material market has to be discussed intensively. From benzethonium-free raw material (batch S2) as well as from batch S1 fraction XI was further fractionated by MPLC and preparative HPLC, leading to a still complex subfraction XIG, which was analyzed by UHPLC/+ESI-QTOF-MS analysis. Advanced data processing and species-metabolite relationship database revealed the tentatively existence of the unusual C-glycosidic flavones derhamnosylmaysin (6), 3'-deoxyrhamnosylmaysin (4), 3'-O-methylderhamnosylmaysin (3), apiferol (2) and alternanthin (8) which might be related to the antiadhesive activity of this subfraction against UPEC. Copyright © 2015 Elsevier B.V. All rights reserved.

Identification of light-independent inhibition of human immunodeficiency virus-1 infection through bioguided fractionation of Hypericum perforatum

PubMed Central

Maury, Wendy; Price, Jason P; Brindley, Melinda A; Oh, ChoonSeok; Neighbors, Jeffrey D; Wiemer, David F; Wills, Nickolas; Carpenter, Susan; Hauck, Cathy; Murphy, Patricia; Widrlechner, Mark P; Delate, Kathleen; Kumar, Ganesh; Kraus, George A; Rizshsky, Ludmila; Nikolau, Basil

2009-01-01

Background Light-dependent activities against enveloped viruses in St. John's Wort (Hypericum perforatum) extracts have been extensively studied. In contrast, light-independent antiviral activity from this species has not been investigated. Results Here, we identify the light-independent inhibition of human immunodeficiency virus-1 (HIV-1) by highly purified fractions of chloroform extracts of H. perforatum. Both cytotoxicity and antiviral activity were evident in initial chloroform extracts, but bioassay-guided fractionation produced fractions that inhibited HIV-1 with little to no cytotoxicity. Separation of these two biological activities has not been reported for constituents responsible for the light-dependent antiviral activities. Antiviral activity was associated with more polar subfractions. GC/MS analysis of the two most active subfractions identified 3-hydroxy lauric acid as predominant in one fraction and 3-hydroxy myristic acid as predominant in the other. Synthetic 3-hydroxy lauric acid inhibited HIV infectivity without cytotoxicity, suggesting that this modified fatty acid is likely responsible for observed antiviral activity present in that fraction. As production of 3-hydroxy fatty acids by plants remains controversial, H. perforatum seedlings were grown sterilely and evaluated for presence of 3-hydroxy fatty acids by GC/MS. Small quantities of some 3-hydroxy fatty acids were detected in sterile plants, whereas different 3-hydroxy fatty acids were detected in our chloroform extracts or field-grown material. Conclusion Through bioguided fractionation, we have identified that 3-hydroxy lauric acid found in field grown Hypericum perforatum has anti-HIV activity. This novel anti-HIV activity can be potentially developed into inexpensive therapies, expanding the current arsenal of anti-retroviral agents. PMID:19594941

Inhalation toxicology. VIII., Establishing heat tolerance limits for rats and mice subjected to acute exposures at elevated air temperatures.

DOT National Transportation Integrated Search

1986-05-01

Experimental animal subjects are used most commonly to assess the toxicity of : thermal decomposition products (smoke) from burning materials. Nascent smoke is : obviously quite hot; therefore, the design of smoke toxicity assay systems must : provid...

Long-Term Effects of Stem Cells on Total-Body Irradiated Mice

NASA Astrophysics Data System (ADS)

Vyalkina, M. V.; Alchinova, I. B.; Yakovenko, E. N.; Medvedeva, Yu S.; Saburina, I. N.; Karganov, M. Yu

2017-01-01

C57Bl/6 mice were exposed to γ-radiation in a sublethal dose of 7.5 Gy. In 3 hours injection 106/mouse of bone marrow multipotent mesenchymal stromal cells stem cells intravenously to experimental group was done. Methods used: body weight measurement, open field behavior, subfraction composition of blood serum (laser correlation spectroscopy, LCS), histological examination of the spleen, liver, and pancreas, count of T and B cells, white blood formula. After 1.5 and 3 months the general trend towards intermediate position of the parameters observed in the experimental between those in intact and irradiated controls attests to partial protective/restorative effects of the injected cells.

Is Transducer Hygiene sufficient when Vaginal Probes are used in the Clinical Routine?

PubMed

Merz, E

2016-04-01

special virucidal wipes on the probes is considered low-level disinfection. Primarily quaternary ammonia compounds are employed for this procedure. This method is easily applicable, has good cleaning characteristics, is effective against HPV and has high skin tolerance. However, it has the disadvantage of not removing all microorganisms during the disinfection process. Immersion procedures are high-level disinfection methods during which the transducer head is dipped in a special fluid for a certain amount of time. The disinfectants used for this include e. g. preparations based on glutaraldehyde or succinic aldehyde. However, in practice immersion disinfection has a number of disadvantages 13: 1. The procedure cannot be validated. 2. The probe permanently attached to the device must be placed in a separate holder and disinfected for at least 15 minutes. This is impracticable in routine operations in a clinic, outpatient facility or practice with a high number of examinations. 3. After this disinfection method, the probe has to be thoroughly rinsed with potable or higher-quality water in order to remove remnants of allergenic or locally toxic substances. 4. Frequently examinations take place in small interior areas with poor ventilation, thus under some circumstances posing an inhalant-related health hazard. 5. The required virucidal effect is frequently not achieved within 15 minutes 13. Furthermore, extended probe contact with liquid disinfecting agents in the long run results in increased wear of the transducer head membrane.Therefore it was interesting to note that in 2009 a fully-automatic disinfection system for ultrasound probes was introduced to the market (Trophon(EPR). This product, developed in Australia, promised relatively rapid high-level disinfection (HLD). During this software-controlled, mechanical disinfection procedure, the entire ultrasound probe (transducer head and handle) is placed in a sealed disinfection chamber, then hydrogen peroxide (H2O2) is

R-loops in bacterial transcription: their causes and consequences.

PubMed

Gowrishankar, J; Leela, J Krishna; Anupama, K

2013-01-01

Nascent untranslated transcripts in bacteria are prone to generating RNA-DNA hybrids (R-loops); Rho-dependent transcription termination acts to reduce their prevalence. Here we discuss the mechanisms of R-loop formation and growth inhibition in bacteria.

GABA Signaling Promotes Synapse Elimination and Axon Pruning in Developing Cortical Inhibitory Interneurons

PubMed Central

Wu, Xiaoyun; Fu, Yu; Knott, Graham; Lu, Jiangteng; Di Cristo, Graziella

2012-01-01

Accumulating evidence indicates that GABA acts beyond inhibitory synaptic transmission and regulates the development of inhibitory synapses in the vertebrate brain, but the underlying cellular mechanism is not well understood. We have combined live imaging of cortical GABAergic axons across time scales from minutes to days with single-cell genetic manipulation of GABA release to examine its role in distinct steps of inhibitory synapse formation in the mouse neocortex. We have shown previously, by genetic knockdown of GABA synthesis in developing interneurons, that GABA signaling promotes the maturation of inhibitory synapses and axons. Here we found that a complete blockade of GABA release in basket interneurons resulted in an opposite effect, a cell-autonomous increase in axon and bouton density with apparently normal synapse structures. These results not only demonstrate that GABA is unnecessary for synapse formation per se but also uncover a novel facet of GABA in regulating synapse elimination and axon pruning. Live imaging revealed that developing GABAergic axons form a large number of transient boutons, but only a subset was stabilized. Release blockade led to significantly increased bouton stability and filopodia density, increased axon branch extension, and decreased branch retraction. Our results suggest that a major component of GABA function in synapse development is transmission-mediated elimination of subsets of nascent contacts. Therefore, GABA may regulate activity-dependent inhibitory synapse formation by coordinately eliminating certain nascent contacts while promoting the maturation of other nascent synapses. PMID:22219294

Origin and heterogeneity of HDL subspecies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nichols, A.V.; Gong, E.L.; Blanche, P.J.

1987-09-01

A major determinant of mature HDL particle size and apolar core content, in the absence of remodeling factors, is most likely the size and apolipoprotein content of the precursor particle. Depending on the number of apoA-I molecules per analog particle, the LCAT-induced transformation follows either a fusion pathway (for precursors with 2 apoA-I per particle) or a pathway (for precursors with more than 2 apoA-I per particle) that conserves the apolipoprotein number. According to our analog results, small nascent HDL probably serve as precursors to the major (apoA-I without apoA-II)-subpopulation in the size interval. Our studies with the large discoidalmore » analog suggest that HDL/sub 2/ (apoA-I without apoA-II)-subpopulations probably originate from the large discoidal nascent HDL that contain a higher number of apolipoprotein molecules per particle than the small nascent HDL. Intermediate transformation products of the large discoidal analog, described in the present study, resemble deformable species found in human lymph and are characterized by a relatively high surface-to-core lipid ratio. Whether large discoidal precursors containing apoE transform in comparable manner but with eventual interchange of apoA-I for apoE (10,15) is under investigation in our laboratory. Likewise, detailed delineation of pathways whereby the (apoA-I with apoA-II)-HDL subpopulations are formed is yet to be accomplished. 23 refs., 6 figs., 2 tabs.« less

Actin cable dynamics and Rho/Rock orchestrate a polarized cytoskeletal architecture in the early steps of assembling a stratified epithelium.

PubMed

Vaezi, Alec; Bauer, Christoph; Vasioukhin, Valeri; Fuchs, Elaine

2002-09-01

To enable stratification and barrier function, the epidermis must permit self-renewal while maintaining adhesive connections. By generating K14-GFP-actin mice to monitor actin dynamics in cultured primary keratinocytes, we uncovered a role for the actin cytoskeleton in establishing cellular organization. During epidermal sheet formation, a polarized network of nascent intercellular junctions and radial actin cables assemble in the apical plane of the monolayer. These actin fibers anchor to a central actin-myosin network, creating a tension-based plane of cytoskeleton across the apical surface of the sheet. Movement of the sheet surface relative to its base expands the zone of intercellular overlap, catalyzing new sites for nascent intercellular junctions. This polarized cytoskeleton is dependent upon alpha-catenin, Rho, and Rock, and its regulation may be important for wound healing and/or stratification, where coordinated tissue movements are involved.

Characterizing the Hygroscopicity of Nascent Sea Spray Aerosol from Synthetic Blooms

NASA Astrophysics Data System (ADS)

Forestieri, S.; Cappa, C. D.; Sultana, C. M.; Lee, C.; Wang, X.; Helgestad, T.; Moore, K.; Prather, K. A.; Cornwell, G.; Novak, G.; Bertram, T. H.

2015-12-01

Marine sea spray aerosol (SSA) particles make up a significant portion of natural aerosols and are therefore important in establishing the baseline for anthropogenic aerosol climate impacts. Scattering of solar radiation by aerosols affects Earth's radiative budget and the degree of scattering is size-dependent. Thus, aerosols scatter more light at elevated relative humidities when they grow larger via water uptake. This growth depends critically on chemical composition. SSA can become enriched in organics during phytoplankton blooms, becoming less salty and therefore less hygroscopic. Subsaturated hygroscopic growth factors at 85% relative humidity (GF(85%)) of SSA particles were quantified during two mesocosm experiments in enclosed marine aerosol reference tanks (MARTs). The two experiments were conducted with filtered seawater collected at separate times from the Scripps Institute of Oceanography Pier in La Jolla, CA. Phytoplankton blooms in each tank were induced via the addition of nutrients and photosynthetically active radiation. The "indoor" MART was illuminated with fluorescent light and the other "outdoor" MART was illuminated with sunlight. The peak chlorophyll-a concentrations were 59 micrograms/L and 341 micrograms /L for the indoor and outdoor MARTs, respectively. GF(85%) values for SSA particles were quantified using a humidified cavity ringdown spectrometer and particle size distributions. Particle composition was monitored with a single particle aerosol mass spectrometer (ATOFMS) and an Aerodyne aerosol mass spectrometer (AMS). Relationships between the observed particle GFs and the particle composition markers will be discussed.

GRADIENT: Graph Analytic Approach for Discovering Irregular Events, Nascent and Temporal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hogan, Emilie

2015-03-31

Finding a time-ordered signature within large graphs is a computationally complex problem due to the combinatorial explosion of potential patterns. GRADIENT is designed to search and understand that problem space.

E-Moderation of Synchronous Discussions in Educational Settings: A Nascent Practice

ERIC Educational Resources Information Center

Schwarz, Baruch B.; Asterhan, Christa S.

2011-01-01

E-moderation has been a common practice in asynchronous discussions of postsecondary courses. We consider here e-moderation of synchronous discussions in the school context. We adopt a design research approach to elaborate an environment, the Argunaut system, that fits the reality of classrooms in which moderation of several small-group…

Insulin-like Growth Factor 1 (IGF-1) Stabilizes Nascent Blood Vessels*

PubMed Central

Jacobo, Sarah Melissa P.; Kazlauskas, Andrius

2015-01-01

Here we report that VEGF-A and IGF-1 differ in their ability to stabilize newly formed blood vessels and endothelial cell tubes. Although VEGF-A failed to support an enduring vascular response, IGF-1 stabilized neovessels generated from primary endothelial cells derived from various vascular beds and mouse retinal explants. In these experimental systems, destabilization/regression was driven by lysophosphatidic acid (LPA). Because previous studies have established that Erk antagonizes LPA-mediated regression, we considered whether Erk was an essential component of IGF-dependent stabilization. Indeed, IGF-1 lost its ability to stabilize neovessels when the Erk pathway was inhibited pharmacologically. Furthermore, stabilization was associated with prolonged Erk activity. In the presence of IGF-1, Erk activity persisted longer than in the presence of VEGF or LPA alone. These studies reveal that VEGF and IGF-1 can have distinct inputs in the angiogenic process. In contrast to VEGF, IGF-1 stabilizes neovessels, which is dependent on Erk activity and associated with prolonged activation. PMID:25564613

Gender Differences in the Relationship of Nascent Conservation and Reading Abilities.

ERIC Educational Resources Information Center

Day, H. D.; Hollingsworth, Shirley

1983-01-01

Researchers investigated the effects of sex differences on the relationship between conservation ability and the reading and linguistic awareness of five-year-old children. Findings of this study and others consistently support the hypothesis that conservation ability correlates more highly with reading in girls than in boys. (Author/PP)

Engaging the public in the nascent era of gravitational-wave astronomy

NASA Astrophysics Data System (ADS)

Hendry, Martin A.

2015-08-01

Within the next few years a global network of ground-based laser interferometers will become fully operational. These ultra-sensitive instruments are confidently expected to directly detect gravitational waves from astrophysical sources before the end of the decade. In anticipation of opening this entirely new window on the Universe, the LIGO (Laser Interferometer Gravitational Wave Observatory) Scientific Collaboration has recently developed a substantive program of education and public outreach activities that includes exhibitions, documentary films, social media and interactive games - as well as more traditional modes of science communication such as schools and public lectures.As the gravitational wave 'detection era' unfolds over the next decade, it will present exciting challenges for future public engagement by the LIGO Scientific Collaboration and by other gravitational-wave astronomy collaborations around the world. Perhaps the most interesting opportunities will be in the area of citizen science, building upon the infrastructure already being developed through e.g. the LIGO Open Science Center (see arXiv:1410.4839) and the remarkable success of the Einstein@Home project (www.einsteinathome.org).In this presentation I will give an overview of the LSC education and public outreach program, highlighting its goals, major successes and future strategy - particularly in relation to the release of future LIGO and other gravitational wave datasets to the scientific community and to the public, and the opportunities this will present for directly engaging citizen scientists in this exciting new field of observational astronomy.

GRADIENT: Graph Analytic Approach for Discovering Irregular Events, Nascent and Temporal

ScienceCinema

Hogan, Emilie

2018-01-16

Finding a time-ordered signature within large graphs is a computationally complex problem due to the combinatorial explosion of potential patterns. GRADIENT is designed to search and understand that problem space.

A Nascent Look at Theoretical Frameworks in Middle Level Education Research

ERIC Educational Resources Information Center

Reyes, Cynthia; Netcoh, Steven

2015-01-01

This paper describes a qualitative content analysis of research articles published on middle level education in the last decade. This analysis was conducted on manuscripts appearing in two premier middle level education journals: "Middle Grades Research Journal" (MGRJ) and "Research in Middle Level Education Online" (RMLE) to…

Characterization of the endolysin from the Enterococcus faecalis bacteriophage VD13

USDA-ARS?s Scientific Manuscript database

Bacteriophage infecting bacteria produce endolysins (peptidoglycan hydrolases) to lyse the host cell from within and release nascent bacteriophage particles. Recombinant endolysins can also lyse Gram-positive bacteria when added exogenously. As a potential alternative to antibiotics, we cloned and...

Data supporting mitochondrial morphological changes by SPG13-associated HSPD1 mutants.

PubMed

Miyamoto, Yuki; Megumi, Funakoshi-Tago; Hasegawa, Nanami; Eguchi, Takahiro; Tanoue, Akito; Tamura, Hiroomi; Yamauchi, Junji

2016-03-01

The data is related to the research article entitled "Hypomyelinating leukodystrophy-associated missense mutation in HSPD1 blunts mitochondrial dynamics" [1]. In addition to hypomyelinating leukodystrophy (HLD) 4 (OMIM no. 612233), it is known that spastic paraplegia (SPG) 13 (OMIM no. 605280) is caused by HSPD1's amino acid mutation. Two amino acid mutations Val-98-to-Ile (V98I) and Gln-461-to-Glu (Q461E) are associated with SPG13 [2]. In order to investigate the effects of HSPD1's V98I or Q461E mutant on mitochondrial morphological changes, we transfected each of the respective mutant-encoding genes into Cos-7 cells. Either of V98I or Q461E mutant exhibited increased number of mitochondria and short length mitochondrial morphologies. Using MitoTracker dye-incorporating assay, decreased mitochondrial membrane potential was also observed in both cases. The data described here supports that SPG13-associated HSPD1 mutant participates in causing aberrant mitochondrial morphological changes with decreased activities.

Unraveling the B. pseudomallei Heptokinase WcbL: From Structure to Drug Discovery

PubMed Central

Vivoli, Mirella; Isupov, Michail N.; Nicholas, Rebecca; Hill, Andrew; Scott, Andrew E.; Kosma, Paul; Prior, Joann L.; Harmer, Nicholas J.

2015-01-01

Summary Gram-negative bacteria utilize heptoses as part of their repertoire of extracellular polysaccharide virulence determinants. Disruption of heptose biosynthesis offers an attractive target for novel antimicrobials. A critical step in the synthesis of heptoses is their 1-O phosphorylation, mediated by kinases such as HldE or WcbL. Here, we present the structure of WcbL from Burkholderia pseudomallei. We report that WcbL operates through a sequential ordered Bi-Bi mechanism, loading the heptose first and then ATP. We show that dimeric WcbL binds ATP anti-cooperatively in the absence of heptose, and cooperatively in its presence. Modeling of WcbL suggests that heptose binding causes an elegant switch in the hydrogen-bonding network, facilitating the binding of a second ATP molecule. Finally, we screened a library of drug-like fragments, identifying hits that potently inhibit WcbL. Our results provide a novel mechanism for control of substrate binding and emphasize WcbL as an attractive anti-microbial target for Gram-negative bacteria. PMID:26687481

Highly Efficient Protein Misfolding Cyclic Amplification

PubMed Central

Ostapchenko, Valeriy G.; Savtchenk, Regina; Alexeeva, Irina; Rohwer, Robert G.; Baskakov, Ilia V.

2011-01-01

Protein misfolding cyclic amplification (PMCA) provides faithful replication of mammalian prions in vitro and has numerous applications in prion research. However, the low efficiency of conversion of PrPC into PrPSc in PMCA limits the applicability of PMCA for many uses including structural studies of infectious prions. It also implies that only a small sub-fraction of PrPC may be available for conversion. Here we show that the yield, rate, and robustness of prion conversion and the sensitivity of prion detection are significantly improved by a simple modification of the PMCA format. Conducting PMCA reactions in the presence of Teflon beads (PMCAb) increased the conversion of PrPC into PrPSc from ∼10% to up to 100%. In PMCAb, a single 24-hour round consistently amplified PrPSc by 600-700-fold. Furthermore, the sensitivity of prion detection in one round (24 hours) increased by 2-3 orders of magnitude. Using serial PMCAb, a 1012-fold dilution of scrapie brain material could be amplified to the level detectible by Western blotting in 3 rounds (72 hours). The improvements in amplification efficiency were observed for the commonly used hamster 263K strain and for the synthetic strain SSLOW that otherwise amplifies poorly in PMCA. The increase in the amplification efficiency did not come at the expense of prion replication specificity. The current study demonstrates that poor conversion efficiencies observed previously have not been due to the scarcity of a sub-fraction of PrPC susceptible to conversion nor due to limited concentrations of essential cellular cofactors required for conversion. The new PMCAb format offers immediate practical benefits and opens new avenues for developing fast ultrasensitive assays and for producing abundant quantities of PrPSc in vitro. PMID:21347353

Isolation and characterization of cyclo-(tryptophanyl-prolyl) and chloramphenicol from Streptomyces sp. SUK 25 with antimethicillin-resistant Staphylococcus aureus activity

PubMed Central

Alshaibani, Muhanna M; Jalil, Juriyati; Sidik, Nik M; Edrada-Ebel, Ruangelie; Zin, Noraziah M

2016-01-01

Background Zingiber spectabile, commonly known as Beehive Ginger, is used as an ethnobotanical plant in many countries as an appetizer or to treat stomachache, toothache, muscle sprain, and as a cure for swelling, sores and cuts. This is the first report of isolation of Streptomyces strain from the root of this plant. Strain Universiti Kebangsaan 25 (SUK 25) has a very high activity to produce secondary metabolites against methicillin-resistant Staphylococcus aureus (MRSA), which is associated with high morbidity and mortality rates due to acquired multidrug resistance genes and causes medication failure in some clinical cases worldwide. Phylogenetic analysis based on the 16S ribosomal RNA gene sequence exhibited that the most closely related strain was Streptomyces omiyaensis NBRC 13449T (99.0% similarity). Aim This study was conducted to carry out the extraction, identification, and biological evaluation of active metabolites isolated from SUK 25 against three MRSA strains, namely, MRSA ATCC 43300, MRSA ATCC 33591, and MRSA ATCC 49476. Materials and methods The production of secondary metabolites by this strain was optimized through Thronton’s media. Isolation, purification, and identification of the bioactive compounds were carried out using reversed-phase high-performance liquid chromatography, high-resolution mass spectrometry, Fourier transform infrared, and one-dimensional and two-dimensional nuclear magnetic resonance. Results During screening procedure, SUK 25 exhibited good antimicrobial potential against several strains of MRSA. The best biological activity was shown from fraction number VII and its subfractions F2 and F3 with minimum inhibitory concentration values at 16 µg/mL and 8 µg/mL, respectively. These two subfractions were identified as diketopiperazine cyclo-(tryptophanyl-prolyl) and chloramphenicol. Conclusion On the basis of obtained results, SUK 25 isolated from Z. spectabile can be regarded as a new valuable source to produce secondary

Low-density lipoprotein electronegativity is a novel cardiometabolic risk factor.

PubMed

Hsu, Jing-Fang; Chou, Tzu-Chieh; Lu, Jonathan; Chen, Shu-Hua; Chen, Fang-Yu; Chen, Ching-Chu; Chen, Jeffrey L; Elayda, MacArthur; Ballantyne, Christie M; Shayani, Steven; Chen, Chu-Huang

2014-01-01

Low-density lipoprotein (LDL) plays a central role in cardiovascular disease (CVD) development. In LDL chromatographically resolved according to charge, the most electronegative subfraction-L5-is the only subfraction that induces atherogenic responses in cultured vascular cells. Furthermore, increasing evidence has shown that plasma L5 levels are elevated in individuals with high cardiovascular risk. We hypothesized that LDL electronegativity is a novel index for predicting CVD. In 30 asymptomatic individuals with metabolic syndrome (MetS) and 27 healthy control subjects, we examined correlations between plasma L5 levels and the number of MetS criteria fulfilled, CVD risk factors, and CVD risk according to the Framingham risk score. L5 levels were significantly higher in MetS subjects than in control subjects (21.9±18.7 mg/dL vs. 11.2±10.7 mg/dL, P:0.01). The Jonckheere trend test revealed that the percent L5 of total LDL (L5%) and L5 concentration increased with the number of MetS criteria (P<0.001). L5% correlated with classic CVD risk factors, including waist circumference, body mass index, waist-to-height ratio, smoking status, blood pressure, and levels of fasting plasma glucose, triglyceride, and high-density lipoprotein. Stepwise regression analysis revealed that fasting plasma glucose level and body mass index contributed to 28% of L5% variance. The L5 concentration was associated with CVD risk and contributed to 11% of 30-year general CVD risk variance when controlling the variance of waist circumference. Our findings show that LDL electronegativity was associated with multiple CVD risk factors and CVD risk, suggesting that the LDL electronegativity index may have the potential to be a novel index for predicting CVD. Large-scale clinical trials are warranted to test the reliability of this hypothesis and the clinical importance of the LDL electronegativity index.

Electronegative Low-density Lipoprotein Increases Coronary Artery Disease Risk in Uremia Patients on Maintenance Hemodialysis

PubMed Central

Chang, Chiz-Tzung; Wang, Guei-Jane; Kuo, Chin-Chi; Hsieh, Ju-Yi; Lee, An-Sean; Chang, Chia-Ming; Wang, Chun-Cheng; Shen, Ming-Yi; Huang, Chiu-Ching; Sawamura, Tatsuya; Yang, Chao-Yuh; Stancel, Nicole; Chen, Chu-Huang

2016-01-01

Abstract Electronegative low-density lipoprotein (LDL) is a recognized factor in the pathogenesis of coronary artery disease (CAD) in the general population, but its role in the development of CAD in uremia patients is unknown. L5 is the most electronegative subfraction of LDL isolated from human plasma. In this study, we examined the distribution of L5 (L5%) and its association with CAD risk in uremia patients. The LDL of 39 uremia patients on maintenance hemodialysis and 21 healthy controls was separated into 5 subfractions, L1–L5, with increasing electronegativity. We compared the distribution and composition of plasma L5 between uremia patients and controls, examined the association between plasma L5% and CAD risk in uremia patients, and studied the effects of L5 from uremia patients on endothelial function. Compared to controls, uremia patients had significantly increased L5% (P < 0.001) and L5 that was rich in apolipoprotein C3 and triglycerides. L5% was significantly higher in uremia patients with CAD (n = 10) than in those without CAD (n = 29) (P < 0.05). Independent of other major CAD risk factors, the adjusted odds ratio for CAD was 1.88 per percent increase in plasma L5% (95% CI, 1.01–3.53), with a near-linear dose–response relationship. Compared with controls, uremia patients had decreased flow-mediated vascular dilatation. In ex vivo studies with preconstricted rat thoracic aortic rings, L5 from uremia patients inhibited acetylcholine-induced relaxation. In cultured human endothelial cells, L5 inhibited endothelial nitric oxide synthase activation and induced endothelial dysfunction. Our findings suggest that elevated plasma L5% may induce endothelial dysfunction and play an important role in the increased risk of CAD in uremia patients. PMID:26765403

Clinical and immunobiochemical characterization of airborne Delonix regia (Gulmohar tree) pollen and cross-reactivity studies with Peltophorum pterocarpum pollen: 2 dominant avenue trees from eastern India.

PubMed

Mandal, Jyotshna; Manna, Prasenjit; Chakraborty, Pampa; Roy, Indrani; Gupta-Bhattacharya, Swati

2009-12-01

Delonix regia and Peltophorum pterocarpum pollen are important aeroallergens for type 1 hypersensitivity in the tropics. The IgE-binding proteins of D regia and their cross-allergenity with P pterocarpum pollen have not been evaluated. To isolate and characterize the IgE-binding proteins of D regia pollen for the first time and to investigate the cross-allergenity with P pterocarpum pollen belonging to the same family (Leguminosae). Allergenic activities were determined by in vivo and in vitro analyses. Pollen extract was fractionated by a combination of 2 columns (diethyl amino ethyl Sephadex and Sephacryl S-200). Protein components were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, periodic acid-Schiff staining, and immunoblotting. In vitro inhibition tests were performed to evaluate the cross-reactivity. The skin prick test results of the patients with respiratory allergies in Calcutta, India, showed 31.1% positivity with D regia pollen. Nine IgE-reactive protein components were found in the crude extract. An optimum IgE-reactive fraction was resolved into 4 subfractions. Subfraction A, which showed maximum IgE reactivity, contained 2 (96- and 66-kDa) IgE-reactive protein components. The 66-kDa component was found to be glycoprotein. Remarkable cross-reactivity between D regia and P pterocarpum pollen was found on IgE enzyme-linked immunosorbent assay inhibition and dot blotting. Shared IgE-binding components (66, 56, 32, 28, 25, and 23 kDa) were observed between D regia and P pterocarpum pollen extracts, whereas the 96- and 43-kDa components were specific to D regia. The purification of the IgE-binding proteins and the identification of the shared/cross-reactive proteins in these taxonomically related pollen members should be helpful for the diagnosis and therapy of patients susceptible to these pollens.

Clinico-immunochemical studies on airborne Areca catechu L. Pollen, a probable risk factor in emergency asthma hospitalization from Eastern India.

PubMed

Chakraborty, Pampa; Mandal, Jyotshna; Sarkar, Eva; Chowdhury, Indrani; Gupta-Bhattacharya, Swati

2009-01-01

The pollen grain of the Areca catechu L. tree is airborne and allergenic. This study aimed to know the role of this pollen as a source of aeroallergen with effect on emergency asthma hospitalization, to isolate its important allergic fraction and to check its cross-reaction with betel nut. Areca pollen was monitored with a Burkard sampler. Determination of allergenic activities was studied by in vivo and in vitro analyses. Asthma hospitalization data were collected from two nearby hospitals. The pollen extract was fractionated by a combination of DEAE-Sephadex and Sephacryl S-200 column. The protein components were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Cross-reactivity of Areca pollen and betel nut was shown by IgE enzyme-linked immunosorbent assay (ELISA) inhibition. The Areca pollen was perennially airborne. Skin test results of respiratory allergic patients showed 38.6% positivity. The detected aeroallergen spots in particle immunoblotting correlated significantly with airborne pollen count. Areca pollen showed a significant positive correlation with asthma hospitalization. There are 6 IgE-reactive protein components in the whole-pollen extract. IgE-reactive fraction 1 was resolved into 4 subfractions. Subfraction 1a showing IgE reactivity contained 3 protein components, among which 2 of 48 and 118 kDa were IgE reactive. The 48-kDa component was reported to be cross-reactive with other palm pollen types. In IgE ELISA inhibition, the betel nut extract showed 50% inhibition with about 110 ng/ml concentration. A. catechu pollen is a significant contributor to the aeroallergen load in India. Its partially purified IgE-reactive fraction may be useful in therapeutics. The betel nut extract showed remarkable cross-reactivity with Areca pollen. Copyright (C) 2009 S. Karger AG, Basel.

Comprehensive Analysis of Established Dyslipidemia-Associated Loci in the Diabetes Prevention Program

PubMed Central

Varga, Tibor V.; Winters, Alexandra H.; Jablonski, Kathleen A.; Horton, Edward S.; Khare-Ranade, Prajakta; Knowler, William C.; Marcovina, Santica M.; Renström, Frida; Watson, Karol E.; Goldberg, Ronald; Florez, José C.

2016-01-01

Background We assessed whether 234 established dyslipidemia-associated loci modify the effects of metformin treatment and lifestyle intervention (vs. placebo control) on lipid and lipid sub-fraction levels in the Diabetes Prevention Program (DPP) randomized controlled trial. Methods and Results We tested gene-treatment interactions in relation to baseline adjusted follow-up blood lipid concentrations (high and low density lipoprotein cholesterol [HDL-C, LDL-C], total cholesterol, triglycerides) and lipoprotein sub-fraction particle concentrations and size in 2,993 participants with pre-diabetes. Of the previously reported SNP associations, 32.5% replicated at P<0.05 with baseline lipid traits. Trait-specific genetic risk scores (GRS) were robustly associated (3×10−4>P>1.1×10−16) with their respective baseline traits for all but two traits. Lifestyle modified the effect of the GRS for large HDL particle numbers, such that each risk allele of the GRSHDL-large was associated with lower concentrations of large HDL particles at follow-up in the lifestyle arm (β=−0.11 μmol/l per GRS risk allele; 95%CI −0.188, −0.033; P=5×10−3; Pinteraction=1×10−3 for lifestyle vs. placebo), but not in the metformin or placebo arms (P>0.05). In the lifestyle arm, participants with high genetic risk had more favorable or similar trait levels at 1-yr compared to participants at lower genetic risk at baseline for 17 of the 20 traits. Conclusions Improvements in large HDL particle concentrations conferred by lifestyle may be diminished by genetic factors. Lifestyle intervention, however, was successful in offsetting unfavorable genetic loading for most lipid traits. PMID:27784733

Structure and biochemical composition of desmosomes and tonofilaments isolated from calf muzzle epidermis

PubMed Central

1978-01-01

Complexes of plasma membrane segments with desmosomes and attached tonofilaments were separated from the stratum spinosum cells of calf muzzle by means of moderately alkaline buffers of low ionic strength and mechanical homogenization. These structures were further fractionated by the use of various treatments including sonication, sucrose gradient centrifugation, and extraction with buffers containing high concentrations of salt, urea, citric acid, or detergents. Subfractions enriched in desmosome-tonofilament-complexes and tonofilament fragments were studied in detail. The desmosome structures such as the midline, the trilaminar membrane profile, and the desmosomal plaque appeared well preserved and were notably resistant to the various treatments employed. Fractions containing desmosome- tonofilament complexes were invariably dominated by the nonmembranous proteins of the tonofilaments which appeared as five major polypeptide bands (apparent molecular weights: 48,000; 51,000; 58,000; 60,000; 68,000) present in molar ratios of approx. 2:1:1:2:2. Four of these polypeptide bands showed electrophoretic mobilities similar to those of prekeratin polypeptides from bovine hoof. However, the largest polypeptide (68,000 mol wt) migrated significantly less in polyacrylamide gels than the largest component of the hoof prekeratin (approximately 63,000 mol wt). In addition, a series of minor bands, including carbohydrate-containing proteins, were identified and concluded to represent constituents of the desmosomal membrane. The analysis of protein-bound carbohydrates (total 270 microgram/mg phospholipid in desmosome-enriched subfractions) showed the presence of relatively high amounts of glucosamine, mannose, galactose, and sialic acids. These data as well as the lipid composition (e.g., high ratio of cholesterol to phospholipids, relatively high contents of sphingomyelin and gangliosides, and fatty acid pattern) indicate that the desmosomal membrane is complex in protein and

Structure and biochemical composition of desmosomes and tonofilaments isolated from calf muzzle epidermis.

PubMed

Drochmans, P; Freudenstein, C; Wanson, J C; Laurent, L; Keenan, T W; Stadler, J; Leloup, R; Franke, W W

1978-11-01

Complexes of plasma membrane segments with desmosomes and attached tonofilaments were separated from the stratum spinosum cells of calf muzzle by means of moderately alkaline buffers of low ionic strength and mechanical homogenization. These structures were further fractionated by the use of various treatments including sonication, sucrose gradient centrifugation, and extraction with buffers containing high concentrations of salt, urea, citric acid, or detergents. Subfractions enriched in desmosome-tonofilament-complexes and tonofilament fragments were studied in detail. The desmosome structures such as the midline, the trilaminar membrane profile, and the desmosomal plaque appeared well preserved and were notably resistant to the various treatments employed. Fractions containing desmosome-tonofilament complexes were invariably dominated by the nonmembranous proteins of the tonofilaments which appeared as five major polypeptide bands (apparent molecular weights: 48,000; 51,000; 58,000; 60,000; 68,000) present in molar ratios of approx. 2:1:1:2:2. Four of these polypeptide bands showed electrophoretic mobilities similar to those of prekeratin polypeptides from bovine hoof. However, the largest polypeptide (68,000 mol wt) migrated significantly less in polyacrylamide gels than the largest component of the hoof prekeratin (approximately 63,000 mol wt). In addition, a series of minor bands, including carbohydrate-containing proteins, were identified and concluded to represent constituents of the desmosomal membrane. The analysis of protein-bound carbohydrates (total 270 microgram/mg phospholipid in desmosome-enriched subfractions) showed the presence of relatively high amounts of glucosamine, mannose, galactose, and sialic acids. These data as well as the lipid composition (e.g., high ratio of cholesterol to phospholipids, relatively high contents of sphingomyelin and gangliosides, and fatty acid pattern) indicate that the desmosomal membrane is complex in protein and

Isolation and Structural Elucidation of Antiproliferative Compounds of Lipidic Fractions from White Shrimp Muscle (Litopenaeus vannamei)

PubMed Central

López-Saiz, Carmen-María; Velázquez, Carlos; Hernández, Javier; Cinco-Moroyoqui, Francisco-Javier; Plascencia-Jatomea, Maribel; Robles-Sánchez, Maribel; Machi-Lara, Lorena; Burgos-Hernández, Armando

2014-01-01

Shrimp is one of the most popular seafood items worldwide, and has been reported as a source of chemopreventive compounds. In this study, shrimp lipids were separated by solvent partition and further fractionated by semi-preparative RP-HPLC and finally by open column chromatography in order to obtain isolated antiproliferative compounds. Antiproliferative activity was assessed by inhibition of M12.C3.F6 murine cell growth using the MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) assay. The methanolic fraction showed the highest antiproliferative activity; this fraction was separated into 15 different sub-fractions (M1–M15). Fractions M8, M9, M10, M12, and M13 were antiproliferative at 100 µg/mL and they were further tested at lower concentrations. Fractions M12 and M13 exerted the highest growth inhibition with an IC50 of 19.5 ± 8.6 and 34.9 ± 7.3 µg/mL, respectively. Fraction M12 was further fractionated in three sub-fractions M12a, M12b, and M12c. Fraction M12a was identified as di-ethyl-hexyl-phthalate, fraction M12b as a triglyceride substituted by at least two fatty acids (predominantly oleic acid accompanied with eicosapentaenoic acid) and fraction M12c as another triglyceride substituted with eicosapentaenoic acid and saturated fatty acids. Bioactive triglyceride contained in M12c exerted the highest antiproliferative activity with an IC50 of 11.33 ± 5.6 µg/mL. Biological activity in shrimp had been previously attributed to astaxanthin; this study demonstrated that polyunsaturated fatty acids are the main compounds responsible for antiproliferative activity. PMID:25526568

CONSEQUENCES OF NON-LINEAR DENSITY EFFECTS ON BUOYANCY AND PLUME BEHAVIOR

EPA Science Inventory

Aquatic plumes, as turbulent streams, grow by entraining ambient water. Buoyant plumes rise and dense ones sink, but, non-linear kinetic effects can reverse the buoyant force in mid-phenomenon. The class of nascent-density plumes begin as buoyant, upwardly accelerating plumes tha...

Fluorescence lifetime imaging of microviscosity changes during ER autophagy in live cells

NASA Astrophysics Data System (ADS)

He, Ying; Samanta, Soham; Gong, Wanjun; Liu, Wufan; Pan, Wenhui; Yang, Zhigang; Qu, Junle

2018-02-01

Unfolded or misfolded protein accumulation inside Endoplasmic Reticulum (ER) will cause ER stress and subsequently will activate cellular autophagy to release ER stress, which would ultimately result in microviscosity changes. However, even though, it is highly significant to gain a quantitative assessment of microviscosity changes during ER autophagy to study ER stress and autophagy behaviors related diseases, it has rarely been reported yet. In this work, we have reported a BODIPY based fluorescent molecular rotor that can covalently bind with vicinal dithiols containing nascent proteins in ER and hence can result in ER stress through the inhibition of the folding of nascent proteins. The change in local viscosity, caused by the release of the stress in cells through autophagy, was quantified by the probe using fluorescence lifetime imaging. This work basically demonstrates the possibility of introducing synthetic chemical probe as a promising tool to diagnose ER-viscosity-related diseases.

Drug-Sensing by the Ribosome Induces Translational Arrest via Active Site Perturbation

PubMed Central

Arenz, Stefan; Meydan, Sezen; Starosta, Agata L.; Berninghausen, Otto; Beckmann, Roland; Vázquez-Laslop, Nora; Wilson, Daniel N.

2014-01-01

SUMMARY During protein synthesis, nascent polypeptide chains within the ribosomal tunnel can act in cis to induce ribosome stalling and regulate expression of downstream genes. The Staphylococcus aureus ErmCL leader peptide induces stalling in the presence of clinically important macrolide antibiotics, such as erythromycin, leading to the induction of the downstream macrolide resistance methyltransferase ErmC. Here, we present a cryo-electron microscopy (EM) structure of the erythromycin-dependent ErmCL-stalled ribosome at 3.9 Å resolution. The structure reveals how the ErmCL nascent chain directly senses the presence of the tunnel-bound drug and thereby induces allosteric conformational rearrangements at the peptidyltransferase center (PTC) of the ribosome. ErmCL-induced perturbations of the PTC prevent stable binding and accommodation of the aminoacyl-tRNA at the A-site leading to inhibition of peptide bond formation and translation arrest. PMID:25306253

Designing symbiosis.

PubMed

Hosoda, Kazufumi; Yomo, Tetsuya

2011-01-01

Organisms rarely live as isolated species and usually show symbiosis in nature. As natural selection is not simple in symbiosis, the establishment and development of symbiosis is still unclear. Insight can be gained by not only retracing the history of well-developed natural symbiotic relationships, but also by observing the development of nascent symbiosis. By using synthetic symbiosis composed of two previously noninteracting populations, we can observe the establishment and its development. We have recently simulated the establishment of nascent symbiosis using two genetically engineered auxotrophic strains of Escherichia coli. One strain, 10 h after mixing with the partner strain, began to oversupply metabolites essential for the partner's growth, eventually leading to continual growth of both strains. Transcriptome analysis revealed that the oversupply was accompanied by global metabolic changes. This study demonstrated that an organism has the potential to adapt to the first encounter with another organism to establish symbiosis.

Arbitrage with fractional Gaussian processes

NASA Astrophysics Data System (ADS)

Zhang, Xili; Xiao, Weilin

2017-04-01

While the arbitrage opportunity in the Black-Scholes model driven by fractional Brownian motion has a long history, the arbitrage strategy in the Black-Scholes model driven by general fractional Gaussian processes is in its infancy. The development of stochastic calculus with respect to fractional Gaussian processes allowed us to study such models. In this paper, following the idea of Shiryaev (1998), an arbitrage strategy is constructed for the Black-Scholes model driven by fractional Gaussian processes, when the stochastic integral is interpreted in the Riemann-Stieltjes sense. Arbitrage opportunities in some fractional Gaussian processes, including fractional Brownian motion, sub-fractional Brownian motion, bi-fractional Brownian motion, weighted-fractional Brownian motion and tempered fractional Brownian motion, are also investigated.

Effects of Aronia melanocarpa constituents on biofilm formation of Escherichia coli and Bacillus cereus.

PubMed

Bräunlich, Marie; Økstad, Ole A; Slimestad, Rune; Wangensteen, Helle; Malterud, Karl E; Barsett, Hilde

2013-12-05

Many bacteria growing on surfaces form biofilms. Adaptive and genetic changes of the microorganisms in this structure make them resistant to antimicrobial agents. Biofilm-forming organisms on medical devices can pose serious threats to human health. Thus, there is a need for novel prevention and treatment strategies. This study aimed to evaluate the ability of Aronia melanocarpa extracts, subfractions and compounds to prevent biofilm formation and to inhibit bacterial growth of Escherichia coli and Bacillus cereus in vitro. It was found that several aronia substances possessed anti-biofilm activity, however, they were not toxic to the species screened. This non-toxic inhibition may confer a lower potential for resistance development compared to conventional antimicrobials.

Biochemical characterization of native Usher protein complexes from a vesicular subfraction of tracheal epithelial cells.

PubMed

Zallocchi, Marisa; Sisson, Joseph H; Cosgrove, Dominic

2010-02-16

Usher syndrome is the major cause of deaf/blindness in the world. It is a genetic heterogeneous disorder, with nine genes already identified as causative for the disease. We noted expression of all known Usher proteins in bovine tracheal epithelial cells and exploited this system for large-scale biochemical analysis of Usher protein complexes. The dissected epithelia were homogenized in nondetergent buffer and sedimented on sucrose gradients. At least two complexes were evident after the first gradient: one formed by specific isoforms of CDH23, PCDH15, and VLGR-1 and a different one at the top of the gradient that included all of the Usher proteins and rab5, a transport vesicle marker. TEM analysis of these top fractions found them enriched in 100-200 nm vesicles, confirming a vesicular association of the Usher complex(es). Immunoisolation of these vesicles confirmed some of the associations already predicted and identified novel interactions. When the vesicles are lysed in the presence of phenylbutyrate, most of the Usher proteins cosediment into the gradient at a sedimentation coefficient of approximately 50 S, correlating with a predicted molecular mass of 2 x 10(6) Da. Although it is still unclear whether there is only one complex or several independent complexes that are trafficked within distinct vesicular pools, this work shows for the first time that native Usher protein complexes occur in vivo. This complex(es) is present primarily in transport vesicles at the apical pole of tracheal epithelial cells, predicting that Usher proteins may be directionally transported as complexes in hair cells and photoreceptors.

PbO2(s, plattnerite) reductive dissolution by natural organic matter: reductant and inhibitory subfractions.

PubMed

Shi, Zhi; Stone, Alan T

2009-05-15

Natural organic matter (NOM) is a diverse collection of molecules, each possessing its own reductant, complexant, and adsorption properties. Here, we are interested in the ability of NOM to bring about the reductive dissolution of Pb(IV)O2(s). Adding the coagulants FeCl3 or Al2(SO4)3 followed by membrane filtration is one way to remove a subset of NOM molecules from surface water samples. Another is to pass water samples through a granular activated carbon (GAC) column. Results from applying these treatments to Great Dismal Swamp water (DSW) and Nequasset Bog Water (NBW) can best be explained as follows: (i) GAC column treatment is more efficient at removing the NOM fraction most responsible for reductive dissolution. (ii) Coagulation/filtration, with either coagulant, is most efficient at removing a second, inhibitory fraction. Inhibition may arise from (i) adsorption at the mineral/water interface, which blocks approach of reductant molecules and (ii) a micelle-like aggregate nature, which provides hydrophobic pockets that capture reductantmolecules, again keeping them away from the mineral/water interface. Hypotheses regarding reductant and inhibitory fractions are further evaluated using representative low-molecular-weight compounds. Substituted hydroquinones are used as mimics of the reductant fraction, and malonic acid, quinic acid, trehalose, alginic acid, and polygalacturonic acid are used as mimics of the inhibitory fraction.

BIOCHEMICAL CHARACTERIZATION OF NATIVE USHER PROTEIN COMPLEXES FROM A VESICULAR SUBFRACTION OF TRACHEAL EPITHELIAL CELLS†

PubMed Central

Zallocchi, Marisa; Sisson, Joseph H.; Cosgrove, Dominic

2010-01-01

Usher syndrome is the major cause of deaf/blindness in the world. It is a genetic heterogeneous disorder, with nine genes already identified as causative for the disease. We noted expression of all known Usher proteins in bovine tracheal epithelial cells, and exploited this system for large-scale biochemical analysis of Usher protein complexes. The dissected epithelia were homogenized in non-detergent buffer, and sedimented on sucrose gradients. At least two complexes were evident after the first gradient: one formed by specific isoforms of CDH23, PCDH15 and VLGR-1, and a different one at the top of the gradient that included all the Usher proteins and rab5, a transport vesicle marker. TEM analysis of these top fractions found them enriched in 100–200 nm vesicles, confirming a vesicular association of the Usher complex(es). Immunoisolation of these vesicles confirmed some of the associations already predicted and identified novel interactions. When the vesicles are lysed in the presence of phenylbutyrate, most of the Usher proteins co-sediment into the gradient at a sedimentation coefficient of approximately 50S, correlating with a predicted molecular mass of 2 × 106 Daltons. Although it is still unclear whether there is only one complex or several independent complexes that are trafficked within distinct vesicular pools, this work shows for the first time that native Usher proteins complexes occur in vivo. This complex(es) is present primarily in transport vesicles at the apical pole of tracheal epithelial cells, predicting that Usher proteins may be directionally transported as complexes in hair cells and photoreceptors. PMID:20058854

Light intermediate chain 1 defines a functional subfraction of cytoplasmic dynein which binds to pericentrin.

PubMed

Tynan, S H; Purohit, A; Doxsey, S J; Vallee, R B

2000-10-20

The light intermediate chains (LICs) of cytoplasmic dynein consist of multiple isoforms, which undergo post-translational modification to produce a large number of species separable by two-dimensional electrophoresis and which we have proposed to represent at least two gene products. Recently, we demonstrated the first known function for the LICs: binding to the centrosomal protein, pericentrin, which represents a novel, non-dynactin-based cargo-binding mechanism. Here we report the cloning of rat LIC1, which is approximately 75% homologous to rat LIC2 and also contains a P-loop consensus sequence. We compared LIC1 and LIC2 for the ability to interact with pericentrin, and found that only LIC1 will bind. A functional P-loop sequence is not required for this interaction. We have mapped the interaction to the central region of both LIC1 and pericentrin. Using recombinant LICs, we found that they form homooligomers, but not heterooligomers, and exhibit mutually exclusive binding to the heavy chain. Additionally, overexpressed pericentrin is seen to interact with endogenous LIC1 exclusively. Together these results demonstrate the existence of two subclasses of cytoplasmic dynein: LIC1-containing dynein, and LIC2-containing dynein, only the former of which is involved in pericentrin association with dynein.

Strand-Specific Analysis of DNA Synthesis and Proteins Association with DNA Replication Forks in Budding Yeast.

PubMed

Yu, Chuanhe; Gan, Haiyun; Zhang, Zhiguo

2018-01-01

DNA replication initiates at DNA replication origins after unwinding of double-strand DNA(dsDNA) by replicative helicase to generate single-stranded DNA (ssDNA) templates for the continuous synthesis of leading-strand and the discontinuous synthesis of lagging-strand. Therefore, methods capable of detecting strand-specific information will likely yield insight into the association of proteins at leading and lagging strand of DNA replication forks and the regulation of leading and lagging strand synthesis during DNA replication. The enrichment and Sequencing of Protein-Associated Nascent DNA (eSPAN), which measure the relative amounts of proteins at nascent leading and lagging strands of DNA replication forks, is a step-wise procedure involving the chromatin immunoprecipitation (ChIP) of a protein of interest followed by the enrichment of protein-associated nascent DNA through BrdU immunoprecipitation. The isolated ssDNA is then subjected to strand-specific sequencing. This method can detect whether a protein is enriched at leading or lagging strand of DNA replication forks. In addition to eSPAN, two other strand-specific methods, (ChIP-ssSeq), which detects potential protein-ssDNA binding and BrdU-IP-ssSeq, which can measure synthesis of both leading and lagging strand, were developed along the way. These methods can provide strand-specific and complementary information about the association of the target protein with DNA replication forks as well as synthesis of leading and lagging strands genome wide. Below, we describe the detailed eSPAN, ChIP-ssSeq, and BrdU-IP-ssSeq protocols.

Environmental surveillance and monitoring the next frontier for pathway-based high throughput screening

EPA Science Inventory

In response to a proposed vision and strategy for toxicity testing in the 21st century nascent high throughput toxicology (HTT) programs have tested thousands of chemicals in hundreds of pathway-based biological assays. Although, to date, use of HTT data for safety assessment of ...

Regulatory Considerations of Lower Cost Air Pollution Sensor Data Performance

EPA Science Inventory

Low-cost, portable air quality sensors could be the next generation of air monitoring, however, this nascent technology is not without risk. This article looks at how the U.S. Environmental Protection Agency (EPA) uses air monitoring data, the procedures followed to ensure and a...

Making Sense of Learning: Insights from an Experientially-Based Undergraduate Entrepreneurship Programme

ERIC Educational Resources Information Center

Blackwood, Tony; Round, Anna; Pugalis, Lee; Hatt, Lucy

2015-01-01

Entrepreneurial learning is complex, reflecting the distinctive dispositions of entrepreneurs (including nascent entrepreneurs at an early stage in their entrepreneurial life course). The surge in entrepreneurship education programmes over recent decades and the attendant increase in scholarship have often contributed to this convoluted field.…

CpG methylation differences between neurons and glia are highly conserved from mouse to human

USDA-ARS?s Scientific Manuscript database

Understanding epigenetic differences that distinguish neurons and glia is of fundamental importance to the nascent field of neuroepigenetics. A recent study used genome-wide bisulfite sequencing to survey differences in DNA methylation between these two cell types, in both humans and mice. That stud...

CDC42 inhibition suppresses progression of incipient intestinal tumors

USDA-ARS?s Scientific Manuscript database

Mutations in the APC or Beta-catenin genes are well-established initiators of colorectal cancer, yet modifiers that facilitate the survival and progression of nascent tumor cells are not well defined. Using genetic and pharmacologic approaches in mouse colorectal cancer and human colorectal cancer x...

77 FR 52683 - UChicago Argonne, LLC, Notice of Decision on Applications for Duty-Free Entry of Scientific...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-30

... science. This instrument is specialized for creating artificial nanoscale structures on an atom-by-atom basis using nascent atom manipulation techniques. The instrument will be used to investigate the amount of force required to move one atom on a materials surface while simultaneously measuring local...

77 FR 42483 - Application(s) for Duty-Free Entry of Scientific Instruments

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-19

... creating artificial nanoscale structures on an atom-by- atom basis using nascent atom manipulation techniques. The instrument will be used to investigate the amount of force required to move one atom on a materials surface while simultaneously measuring local electronic structural changes during atom movement...

Transcriptomic and metabolic responses of Staphylococcus aureus in mixed culture with Lactobacillus plantarum, Streptococcus thermophilus and Enterococcus durans in milk.

PubMed

Zdenkova, Kamila; Alibayov, Babek; Karamonova, Ludmila; Purkrtova, Sabina; Karpiskova, Renata; Demnerova, Katerina

2016-09-01

Staphylococcus aureus is a major food-borne pathogen due to the production of enterotoxin and is particularly prevalent in contaminated milk and dairy products. The lactic acid bacteria (LAB) are widely used as biocontrol agents in fermented foods which can inhibit pathogenic flora. In our work, we investigated the influence of three strains of LAB (Lactobacillus plantarum, Streptococcus thermophilus and Enterococcus durans) on the relative expression of three enterotoxin genes (sea, sec, sell) and eight virulence and/or regulatory genes (sarA, saeS, codY, srrA, rot, hld/RNAIII, agrA/RNAII, sigB) in two S. aureus strains (MW2 and Sa1612) in TSB and reduced-fat milk (1.5 %) at 30 °C over a 24-h period. The tested LAB and S. aureus strains proved to be mutually non-competitive or only slightly competitive during co-cultivation. In addition, under the above-mentioned conditions, differential gene expression between the S. aureus MW2 and Sa1612 strains was well documented. S. aureus growth was changed in mixed culture with LAB; however, its effect on the repression of sea and sec expression correlated with production of these virulence factors. In comparison, the presence of LAB strains generally inhibited the expression of sec, sell, sarA, seaS, agrA/RNAII and hld/RNAIII genes. The effect of LAB strains presence on the expression of sea, codY, srrA, rot and sigB genes was medium, time, LAB and S. aureus strain specific. SEA and SEC production was significantly reduced in milk compared to TSB in pure culture. After the 24-h cultivation, S. aureus MW2 and Sa1612 SEC production was 187 and 331 times lower in milk compared to TSB, respectively (0.07 and 0.39 ng/mL in milk, versus 13.1 and 129.2 ng/mL in TSB, respectively). At the same time S. aureus MW2 and Sa1612 SEA production was 77 and 68 times lower in milk compared to TSB, respectively (0.99 and 0.17 ng/mL in milk, versus 76.4 and 11.5 ng/mL in TSB, respectively). This study has revealed new insights into the

Do Simulations Enhance Student Learning? An Empirical Evaluation of an IR Simulation

ERIC Educational Resources Information Center

Shellman, Stephen M.; Turan, Kursad

2006-01-01

There is a nascent literature on the question of whether active learning methods, and in particular simulation methods, enhance student learning. In this article, the authors evaluate the utility of an international relations simulation in enhancing learning objectives. Student evaluations provide evidence that the simulation process enhances…

Surviving Troubled Times: Five Best Practices for Training Solutions

ERIC Educational Resources Information Center

Villachica, Steven W.; Stepich, Donald A.; Rist, Shannon

2011-01-01

The business of training and performance improvement has always been cyclical, with the fortunes of human resource development (HRD) and performance improvement professionals rising and falling with the economic fortunes of the workplace. The current economic downturn and nascent recovery represent an opportunity for HRD and performance…

Self-Efficacy for Resolving Environmental Uncertainties: Implications for Entrepreneurial Educational and Support Programs

ERIC Educational Resources Information Center

Pushkarskaya, Helen; Usher, Ellen L.

2010-01-01

Using a unique sample of rural Kentucky residents, we demonstrated that, in the domain of operational and competitive environmental uncertainties, self-efficacy beliefs are significantly higher among nascent entrepreneurs than among non-entrepreneurs. We employed the hierarchical logistic regression analysis to demonstrate that this result is…

A Feminist Posthumanist Political Ecology of Education for Theorizing Human-Animal Relations/Relationships

ERIC Educational Resources Information Center

Lloro-Bidart, Teresa

2017-01-01

This paper contributes to a nascent conversation in environmental education (EE) research by using ethnographic data and extant theory to develop a feminist posthumanist political ecology of education for theorizing human-animal relations/relationships. Specifically, I (1) engage feminist methodologies and theories; (2) give epistemological and…

Love and Resistance of Mothers with Intellectual Disability from Ethnocultural Communities in Canada

ERIC Educational Resources Information Center

Pacheco, Laura; McConnell, David

2017-01-01

Background: Mothers with intellectual disability are thought to be passive, dependent and in need of protection. This study contributes to a nascent body of research that challenges this schema, revealing how women with intellectual disability who are mothers resist oppression. Methods: Narrative research methods underpinned by intersectionality…

Cultural Invariance of Goal Orientation and Self-Efficacy in New Zealand: Relations with Achievement

ERIC Educational Resources Information Center

Meissel, Kane; Rubie-Davies, Christine M.

2016-01-01

Background: There is substantial evidence indicating that various psychological processes are affected by cultural context, but such research is comparatively nascent within New Zealand. As there are four large cultural groups in New Zealand, representing an intersection of individualist, collectivist, indigenous, colonial, and immigrant cultures,…

Origin and domestication of papaya Yh chromosome

USDA-ARS?s Scientific Manuscript database

Sex in papaya is controlled by a pair of nascent sex chromosomes. Females are XX, and two slightly different Y chromosomes distinguish males (XY) and hermaphrodites (XYh). The hermaphrodite-specific region of the Yh chromosome (HSY) and its X chromosome counterpart were sequenced and analyzed previo...

Discovering Entrepreneurship: An Exploration of a Tripartite Approach to Developing Entrepreneurial Capacities

ERIC Educational Resources Information Center

Collins, Lorna A.; Smith, Alison J.; Hannon, Paul D.

2006-01-01

Purpose: To describe an exploration in the use of synergistic learning methods in the delivery of an innovative pilot programme designed to teach entrepreneurship capacities. The programme took a tripartite approach involving nascent entrepreneurs, existing entrepreneurs and facilitators using an action research and action learning approach.…

Cognitive Development, Epistemic Doubt, and Identity Formation in Adolescence.

ERIC Educational Resources Information Center

Boyes, Michael C.; Chandler, Michael

1992-01-01

To evaluate the part that nascent skeptical doubt plays in shaping adolescent social-cognitive development, 61 high school students clearly classified as in concrete or formal operational stages of cognitive development completed a measure of epistemic stances. A relationship was found between cognitive and epistemic development. (SLD)

The structure of Escherichia coli signal recognition particle revealed by scanning transmission electron microscopy.

PubMed

Mainprize, Iain L; Beniac, Daniel R; Falkovskaia, Elena; Cleverley, Robert M; Gierasch, Lila M; Ottensmeyer, F Peter; Andrews, David W

2006-12-01

Structural studies on various domains of the ribonucleoprotein signal recognition particle (SRP) have not converged on a single complete structure of bacterial SRP consistent with the biochemistry of the particle. We obtained a three-dimensional structure for Escherichia coli SRP by cryoscanning transmission electron microscopy and mapped the internal RNA by electron spectroscopic imaging. Crystallographic data were fit into the SRP reconstruction, and although the resulting model differed from previous models, they could be rationalized by movement through an interdomain linker of Ffh, the protein component of SRP. Fluorescence resonance energy transfer experiments determined interdomain distances that were consistent with our model of SRP. Docking our model onto the bacterial ribosome suggests a mechanism for signal recognition involving interdomain movement of Ffh into and out of the nascent chain exit site and suggests how SRP could interact and/or compete with the ribosome-bound chaperone, trigger factor, for a nascent chain during translation.

Both DNA Polymerases δ and ε Contact Active and Stalled Replication Forks Differently

PubMed Central

Yu, Chuanhe; Gan, Haiyun

2017-01-01

ABSTRACT Three DNA polymerases, polymerases α, δ, and ε (Pol α, Pol δ, and Pol ε), are responsible for eukaryotic genome duplication. When DNA replication stress is encountered, DNA synthesis stalls until the stress is ameliorated. However, it is not known whether there is a difference in the association of each polymerase with active and stalled replication forks. Here, we show that each DNA polymerase has a distinct pattern of association with active and stalled replication forks. Pol α is enriched at extending Okazaki fragments of active and stalled forks. In contrast, although Pol δ contacts the nascent lagging strands of active and stalled forks, it binds to only the matured (and not elongating) Okazaki fragments of stalled forks. Pol ε has greater contact with the nascent single-stranded DNA (ssDNA) of the leading strand on active forks than on stalled forks. We propose that the configuration of DNA polymerases at stalled forks facilitates the resumption of DNA synthesis after stress removal. PMID:28784720

Translational Science by Public Biotechnology Companies in the IPO“Class of 2000”: The Impact of Technological Maturity

PubMed Central

McNamee, Laura; Ledley, Fred

2013-01-01

The biotechnology industry plays a central role in the translation of nascent biomedical science into both products that offer material health benefits and creating capital growth. This study examines the relationship between the maturity of technologies in a characteristic life cycle and value creation by biotechnology companies. We examined the core technology, product development pipelines, and capitalization for a cohort of biotechnology companies that completed an IPO in 2000. Each of these companies was well financed and had core technologies on the leading edge of biological science. We found that companies with the least mature technologies had significantly higher valuations at IPO, but failed to develop products based on these technologies over the ensuing decade, and created less capital growth than companies with more mature technologies at IPO. The observation that this cohort of recently public biotechnology companies was not effective in creating value from nascent science suggests the need for new, evidence-based business strategies for translational science. PMID:24358154

NT3-chitosan elicits robust endogenous neurogenesis to enable functional recovery after spinal cord injury

PubMed Central

Yang, Zhaoyang; Zhang, Aifeng; Duan, Hongmei; Zhang, Sa; Hao, Peng; Ye, Keqiang; Sun, Yi E.; Li, Xiaoguang

2015-01-01

Neural stem cells (NSCs) in the adult mammalian central nervous system (CNS) hold the key to neural regeneration through proper activation, differentiation, and maturation, to establish nascent neural networks, which can be integrated into damaged neural circuits to repair function. However, the CNS injury microenvironment is often inhibitory and inflammatory, limiting the ability of activated NSCs to differentiate into neurons and form nascent circuits. Here we report that neurotrophin-3 (NT3)-coupled chitosan biomaterial, when inserted into a 5-mm gap of completely transected and excised rat thoracic spinal cord, elicited robust activation of endogenous NSCs in the injured spinal cord. Through slow release of NT3, the biomaterial attracted NSCs to migrate into the lesion area, differentiate into neurons, and form functional neural networks, which interconnected severed ascending and descending axons, resulting in sensory and motor behavioral recovery. Our study suggests that enhancing endogenous neurogenesis could be a novel strategy for treatment of spinal cord injury. PMID:26460015

Prion-Associated Toxicity is Rescued by Elimination of Cotranslational Chaperones

PubMed Central

Keefer, Kathryn M.; True, Heather L.

2016-01-01

The nascent polypeptide-associated complex (NAC) is a highly conserved but poorly characterized triad of proteins that bind near the ribosome exit tunnel. The NAC is the first cotranslational factor to bind to polypeptides and assist with their proper folding. Surprisingly, we found that deletion of NAC subunits in Saccharomyces cerevisiae rescues toxicity associated with the strong [PSI+] prion. This counterintuitive finding can be explained by changes in chaperone balance and distribution whereby the folding of the prion protein is improved and the prion is rendered nontoxic. In particular, the ribosome-associated Hsp70 Ssb is redistributed away from Sup35 prion aggregates to the nascent chains, leading to an array of aggregation phenotypes that can mimic both overexpression and deletion of Ssb. This toxicity rescue demonstrates that chaperone modification can block key steps of the prion life cycle and has exciting implications for potential treatment of many human protein conformational disorders. PMID:27828954

Transmembrane Segments Form Tertiary Hairpins in the Folding Vestibule of the Ribosome.

PubMed Central

Tu, LiWei; Khanna, Pooja; Deutsch, Carol

2013-01-01

Folding of membrane proteins begins in the ribosome as the peptide is elongated. During this process, the nascent peptide navigates along 100 Å of tunnel from the peptidyltransferase center to the exit port. Proximal to the exit port is a ‘folding vestibule’ that permits the nascent peptide to compact and explore conformational space for potential tertiary folding partners. The latter occurs for cytosolic subdomains, but has not yet been shown for transmembrane segments. We now demonstrate, using an accessibility assay and an improved, intramolecular crosslinking assay, that the helical transmembrane S3b-S4 hairpin (‘paddle’) of a voltage-gated potassium (Kv) channel, a critical region of the Kv voltage sensor, forms in the vestibule. S3-S4 hairpin interactions are detected at an early stage of Kv biogenesis. Moreover, this vestibule hairpin is consistent with a closed-state conformation of the Kv channel in the plasma membrane. PMID:24055377