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Sample records for coli twin-arginine translocation

  1. Yersinia enterocolitica and Photorhabdus asymbiotica β-lactamases BlaA are exported by the twin-arginine translocation pathway.

    Science.gov (United States)

    Schriefer, Eva-Maria; Hoffmann-Thoms, Stephanie; Schmid, Franz X; Schmid, Annika; Heesemann, Jürgen

    2013-01-01

    In general, β-lactamases of medically important Gram-negative bacteria are Sec-dependently translocated into the periplasm. In contrast, β-lactamases of Mycobacteria spp. (BlaC, BlaS) and the Gram-negative environmental bacteria Stenotrophomonas maltophilia (L2) and Xanthomonas campestris (Bla(XCC-1)) have been reported to be secreted by the twin-arginine translocation (Tat) system. Yersinia enterocolitica carries 2 distinct β-lactamase genes (blaA and blaB) encoding BlaA(Ye) and the AmpC-like β-lactamase BlaB, respectively. By using the software PRED-TAT for prediction and discrimination of Sec from Tat signal peptides, we identified a functional Tat signal sequence for Yersinia BlaA(Ye). The Tat-dependent translocation of BlaA(Ye) could be clearly demonstrated by using a Y. enterocolitica tatC-mutant and cell fractionation. Moreover, we could demonstrate a unique unusual temperature-dependent activity profile of BlaA(Ye) ranging from 15 to 60 °C and a high 'melting temperature' (T(M)=44.3°) in comparison to the related Sec-dependent β-lactamase TEM-1 (20-50°C, T(M)=34.9 °C). Strikingly, the blaA gene of Y. enterocolitica is present in diverse environmental Yersinia spp. and a blaA homolog gene could be identified in the closely related Photorhabdus asymbiotica (BlaA(Pa); 69% identity to BlaA(Ye)). For BlaA(Pa) of P. asymbiotica, we could also demonstrate Tat-dependent secretion. These results suggest that Yersinia BlaA-related β-lactamases may be the prototype of a large Tat-dependent β-lactamase family, which originated from environmental bacteria. Copyright © 2012 Elsevier GmbH. All rights reserved.

  2. Effects of altered TatC proteins on protein secretion efficiency via the twin-arginine translocation pathway of Bacillus subtilis

    NARCIS (Netherlands)

    Eijlander, Robyn T.; Kolbusz, Magdalena A.; Berendsen, Erwin M.; Kuipers, Oscar P.

    Protein translocation via the Tat machinery in thylakoids and bacteria occurs through a cooperation between the TatA, TatB and TatC subunits, of which the TatC protein forms the initial Tat substrate-binding site. The Bacillus subtilis Tat machinery lacks TatB and comprises two separate TatAC

  3. The Hydrophobic Region of the DmsA Twin-Arginine Leader Peptide Determines Specificity with Chaperone DmsD

    OpenAIRE

    Winstone, Tara M. L.; Tran, Vy A.; Turner, Raymond J.

    2013-01-01

    The system specific chaperone DmsD plays a role in the maturation of the catalytic subunit of dimethyl sulfoxide (DMSO) reductase, DmsA. Pre-DmsA contains a 45-amino acid twin-arginine leader peptide that is important for targeting and translocation of folded and cofactor-loaded DmsA by the twin-arginine translocase. DmsD has previously been shown to interact with the complete twin-arginine leader peptide of DmsA. In this study, isothermal titration calorimetry was used to investigate the the...

  4. Comparative analysis of twin-arginine (Tat)-dependent protein secretion of a heterologous model protein (GFP) in three different Gram-positive bacteria

    NARCIS (Netherlands)

    Meissner, Daniel; Vollstedt, Angela; van Dijl, Jan Maarten; Freudl, Roland

    In contrast to the general protein secretion (Sec) system, the twin-arginine translocation (Tat) export pathway allows the translocation of proteins across the bacterial plasma membrane in a fully folded conformation. Due to this feature, the Tat pathway provides an attractive alternative to the

  5. Mapping the signal peptide binding and oligomer contact sites of the core subunit of the pea twin arginine protein translocase.

    Science.gov (United States)

    Ma, Xianyue; Cline, Kenneth

    2013-03-01

    Twin arginine translocation (Tat) systems of thylakoid and bacterial membranes transport folded proteins using the proton gradient as the sole energy source. Tat substrates have hydrophobic signal peptides with an essential twin arginine (RR) recognition motif. The multispanning cpTatC plays a central role in Tat operation: It binds the signal peptide, directs translocase assembly, and may facilitate translocation. An in vitro assay with pea (Pisum sativum) chloroplasts was developed to conduct mutagenesis and analysis of cpTatC functions. Ala scanning mutagenesis identified mutants defective in substrate binding and receptor complex assembly. Mutations in the N terminus (S1) and first stromal loop (S2) caused specific defects in signal peptide recognition. Cys matching between substrate and imported cpTatC confirmed that S1 and S2 directly and specifically bind the RR proximal region of the signal peptide. Mutations in four lumen-proximal regions of cpTatC were defective in receptor complex assembly. Copurification and Cys matching analyses suggest that several of the lumen proximal regions may be important for cpTatC-cpTatC interactions. Surprisingly, RR binding domains of adjacent cpTatCs directed strong cpTatC-cpTatC cross-linking. This suggests clustering of binding sites on the multivalent receptor complex and explains the ability of Tat to transport cross-linked multimers. Transport of substrate proteins cross-linked to the signal peptide binding site tentatively identified mutants impaired in the translocation step.

  6. The hydrophobic core of twin-arginine signal sequences orchestrates specific binding to Tat-pathway related chaperones.

    Directory of Open Access Journals (Sweden)

    Anitha Shanmugham

    Full Text Available Redox enzyme maturation proteins (REMPs bind pre-proteins destined for translocation across the bacterial cytoplasmic membrane via the twin-arginine translocation system and enable the enzymatic incorporation of complex cofactors. Most REMPs recognize one specific pre-protein. The recognition site usually resides in the N-terminal signal sequence. REMP binding protects signal peptides against degradation by proteases. REMPs are also believed to prevent binding of immature pre-proteins to the translocon. The main aim of this work was to better understand the interaction between REMPs and substrate signal sequences. Two REMPs were investigated: DmsD (specific for dimethylsulfoxide reductase, DmsA and TorD (specific for trimethylamine N-oxide reductase, TorA. Green fluorescent protein (GFP was genetically fused behind the signal sequences of TorA and DmsA. This ensures native behavior of the respective signal sequence and excludes any effects mediated by the mature domain of the pre-protein. Surface plasmon resonance analysis revealed that these chimeric pre-proteins specifically bind to the cognate REMP. Furthermore, the region of the signal sequence that is responsible for specific binding to the corresponding REMP was identified by creating region-swapped chimeric signal sequences, containing parts of both the TorA and DmsA signal sequences. Surprisingly, specificity is not encoded in the highly variable positively charged N-terminal region of the signal sequence, but in the more similar hydrophobic C-terminal parts. Interestingly, binding of DmsD to its model substrate reduced membrane binding of the pre-protein. This property could link REMP-signal peptide binding to its reported proofreading function.

  7. Roles of the twin-arginine translocase and associated chaperones in the biogenesis of the electron transport chains of the human pathogen Campylobacter jejuni.

    Science.gov (United States)

    Hitchcock, Andrew; Hall, Stephen J; Myers, Jonathan D; Mulholland, Francis; Jones, Michael A; Kelly, David J

    2010-10-01

    The zoonotic pathogen Campylobacter jejuni NCTC 11168 uses a complex set of electron transport chains to ensure growth with a variety of electron donors and alternative electron acceptors, some of which are known to be important for host colonization. Many of the key redox proteins essential for electron transfer in this bacterium have N-terminal twin-arginine translocase (TAT) signal sequences that ensure their transport across the cytoplasmic membrane in a folded state. By comparisons of 2D gels of periplasmic extracts, gene fusions and specific enzyme assays in wild-type, tatC mutant and complemented strains, we experimentally verified the TAT dependence of 10 proteins with an N-terminal twin-arginine motif. NrfH, which has a TAT-like motif (LRRKILK), was functional in nitrite reduction in a tatC mutant, and was correctly rejected as a TAT substrate by the tatfind and TatP prediction programs. However, the hydrogenase subunit HydA is also rejected by tatfind, but was shown to be TAT-dependent experimentally. The YedY homologue Cj0379 is the only TAT translocated molybdoenzyme of unknown function in C. jejuni; we show that a cj0379c mutant is deficient in chicken colonization and has a nitrosative stress phenotype, suggestive of a possible role for Cj0379 in the reduction of reactive nitrogen species in the periplasm. Only two potential TAT chaperones, NapD and Cj1514, are encoded in the genome. Surprisingly, despite homology to TorD, Cj1514 was shown to be specifically required for the activity of formate dehydrogenase, not trimethylamine N-oxide reductase, and was designated FdhM.

  8. Probiotic Mixture Golden Bifido Prevents Neonatal Escherichia coli K1 Translocation via Enhancing Intestinal Defense

    OpenAIRE

    Qing Zeng; Xiaolong He; Santhosh Puthiyakunnon; Hansen Xiao; Zelong Gong; Swapna Boddu; Lecheng Chen; Huiwen Tian; Huiwen Tian; Sheng-He Huang; Sheng-He Huang; Hong Cao

    2017-01-01

    Escherichia coli (E. coli) K1 sepsis and meningitis is a severe infection characterized by high mortality in neonates. Successful colonization and translocation across the intestinal mucosa have been regarded as the critical steps for E. coli K1 sepsis and meningitis. We recently reported that the probiotic mixture, Golden Bifido (containing live Lactobacillus bulgaricus, Bifidobacterium, and Streptococcus thermophilus, LBS) has a preventive role against neonatal E. coli K1 bacteremia and men...

  9. The Enzymology of Protein Translocation across the Escherichia coli Plasma Membrane

    NARCIS (Netherlands)

    Wickner, William; Driessen, Arnold J.M.; Hartl, Franz-Ulrich

    1991-01-01

    Converging physiological, genetic, and biochemical studies have established the salient features of preprotein translocation across the plasma membrane of Escherichia coli. Translocation is catalyzed by two proteins, a soluble chaperone and a membrane-bound translocase. SecB, the major chaperone for

  10. Probiotic Mixture Golden Bifido Prevents Neonatal Escherichia coli K1 Translocation via Enhancing Intestinal Defense

    Directory of Open Access Journals (Sweden)

    Qing Zeng

    2017-09-01

    Full Text Available Escherichia coli (E. coli K1 sepsis and meningitis is a severe infection characterized by high mortality in neonates. Successful colonization and translocation across the intestinal mucosa have been regarded as the critical steps for E. coli K1 sepsis and meningitis. We recently reported that the probiotic mixture, Golden Bifido (containing live Lactobacillus bulgaricus, Bifidobacterium, and Streptococcus thermophilus, LBS has a preventive role against neonatal E. coli K1 bacteremia and meningitis. However, the interaction between the neonatal gut barrier, probiotics and E. coli K1 is still not elucidated. The present study aims to investigate how LBS exerts its protective effects on neonatal gut barrier during E. coli K1 infection. The beneficial effects of LBS were explored in vitro and in vivo using human colon carcinoma cell lines HT-29 and rat model of neonatal E. coli K1 infection, respectively. Our results showed that stimulation with E. coli K1 was able to cause intestinal barrier dysfunction, which were reflected by E. coli K1-induced intestinal damage and apoptosis of intestinal epithelial cells, reduction of mucin, immunoglobulin A (IgA and tight junction proteins expression, as well as increase in intestinal permeability, all these changes facilitate E. coli K1 intestinal translocation. However, these changes were alleviated when HT-29 cells were treated with LBS before E. coli K1 infection. Furthermore, we found that LBS-treated neonatal rats (without E. coli K1 infection have showed higher production of mucin, ZO-1, IgA, Ki67 in intestinal mucosa as well as lower intestinal permeability than that of non-treated rats, indicating that LBS could accelerate the development of neonatal intestinal defense. Taken together, our results suggest that enhancement of the neonatal intestinal defense to fight against E. coli K1 translocation could be the potential mechanism to elucidate how LBS confers a protective effect against neonatal E

  11. Assessment of bacterial translocation in obstructive jaundice using Tc-99m Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Diniz, Simone Odilia Fernandes; Nelson, David Lee [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Faculdade de Farmacia]. E-mail: simone@farmacia.ufmg.br; Barbosa, Alfredo Jose Afonso; Araujo, Ivana Durval; Machado, Leonardo Augusto da Silva [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Faculdade de Medicina; Bernardo Filho, Mario [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Dept. de Biofisica e Biometria

    2005-10-15

    In obstructive jaundice, the passage of bacteria and endotoxins through the intestine wall to reach the systemic circulation is associated with septicemia, renal failure and pulmonary dysfunction. The aim of this work was to investigate bacterial translocation utilizing {sup 99m} Tc-E.coli in an experimental model of obstructive jaundice. The levels of bilirubin in rats that were subjected to ligature of the bile duct were significantly increased when compared to control animals (p < 0.001). The biodistribution results did not show any translocation of {sup 99m} Tc-E.coli to the mesenteric lymphatic nodules, liver, spleen or lungs of the rats that suffered ligature of the bile duct (p > 0.05). The evaluation of the intestinal permeability using 'per os' administration of {sup 99m} Tc-DTPA showed 1.61 {+-} 0.57% and 1.39 {+-} 0.72% of radioactivity in the urine of the control and jaundice animals, respectively. The histological analysis of the distal wall of the ileum showed that the covering epithelium and the crypt were morphologically preserved in both groups. The seven-day period after the ligature of the bile duct may not have been long enough to promote modifications in intestinal wall to occur so as to permit the passage of Tc-99m E.coli. (author)

  12. The effect of E coli virulence on bacterial translocation and systemic sepsis in the neonatal rabbit model.

    Science.gov (United States)

    Jackson, R J; Smith, S D; Wadowsky, R M; DePudyt, L; Rowe, M I

    1991-04-01

    In the surgical neonate, three factors that promote bacterial translocation and systemic infection are: (1) intestinal bacterial colonization and overgrowth; (2) compromised host defenses; and (3) disruption of the mucosal epithelial barrier. The newborn rabbit provides an excellent model to study these factors. Like the human, there is early closure of the gut mucosa to macromolecules, and nutrition can be maintained by breast or formula feeding. This study examines translocation and systemic sepsis after colonization with virulent K1 and avirulent K100 strains of Escherichia coli. New Zealand white rabbit pups (2 to 5 days old) were studied. The gastrointestinal tracts of 12 were colonized with K1 E coli; 14 were colonized with K100 E coli; 12 control animals were not inoculated. Mesenteric lymph node (MLN), liver, spleen, and colon homogenate were cultured 72 hours postinoculation. No bacteria were isolated from the colons of all but one control animal. Translocation or systemic sepsis did not occur. Translocation to the MLN was significantly increased (P less than .03) in K1 (50%) and K100 (36%) groups compared with controls (0%). Translocation to liver and spleen (systemic sepsis) was significantly increased (P less than .03) in K1 animals (67%) compared with K100 (0%) or controls (0%). Colonization by both strains of E coli led to translocation to the MLN, but only K1 E coli caused systemic sepsis. This suggests that although colonization by E coli in the newborn leads to translocation to the MLN, progression to systemic sepsis is the result of characteristics of the bacteria and/or neonatal host responses.

  13. [Dermohypodermitis and gut translocation Escherichia coli septicemia in a newborn infant].

    Science.gov (United States)

    Gouache, E; Chantier, E; Hubert, N; Rivière, M-F

    2013-01-01

    The burden of neonatal bacterial infections continues. They remain a significant cause of death and morbidity, despite recommendations for prevention. The epidemiology of these infections has changed. Currently the two most causative pathogens for early-onset neonatal sepsis and for late-onset sepsis in term infants are Group B streptococci (GBS) and Escherichia coli. E. coli's role is increasingly important since the widespread use of intrapartum antibiotic prophylaxis. In late-onset infections, one of the suggested pathophysiological mechanisms is microbial translocation in the gut secondary to digestive colonization, particularly when E. coli is isolated in blood cultures. This can occur either before or after birth. Bacterial sepsis can be associated with various non-specific peripheral manifestations involving skin and soft tissues. We report the case of a full-term, 26-day-old newborn admitted to the hospital for fever. She presented with dermohypodermitis of the left trunk and was diagnosed with E. coli septicemia. She was discharged in good condition after appropriate intravenous antibiotic therapy. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  14. Protein chaperones Q8ZP25_SALTY from Salmonella typhimurium and HYAE_ECOLI from Escherichia coli exhibit thioredoxin-like structures despite lack of canonical thioredoxin active site sequence motive

    Science.gov (United States)

    Parish, David; Benach, Jordi; Liu, Goahua; Singarapu, Kiran Kumar; Xiao, Rong; Acton, Thomas; Su, Min; Bansal, Sonal; Prestegard, James H.; Hunt, John; Montelione, Gaetano T.

    2010-01-01

    The structure of the 142-residue protein Q8ZP25_SALTY encoded in the genome of Salmonella typhimurium LT2 was determined independently by NMR and X-ray crystallography, and the structure of the 140-residue protein HYAE_ECOLI encoded in the genome of Eschericia coli was determined by NMR. The two proteins belong to Pfam [1] PF07449, which currently comprises 50 members, and belongs itself to the ‘thioredoxin-like clan’. However, protein HYAE_ECOLI and the other proteins of Pfam PF07449 do not contain the canonical Cys-X-X-Cys active site sequence motif of thioredoxin. Protein HYAE_ECOLI was previously classified as a [NiFe] hydrogenase-1 specific chaperone interacting with the twin-arginine translocation (Tat) signal peptide. The structures presented here exhibit the expected thioredoxin-like fold and support the view that members of Pfam family PF07449 specifically interact with Tat signal peptides. PMID:19039680

  15. Assessment of bacterial translocation in obstructive jaundice using Tc-99m Escherichia coli

    International Nuclear Information System (INIS)

    Diniz, Simone Odilia Fernandes; Nelson, David Lee; Barbosa, Alfredo Jose Afonso; Araujo, Ivana Durval; Machado, Leonardo Augusto da Silva; Bernardo Filho, Mario

    2005-01-01

    In obstructive jaundice, the passage of bacteria and endotoxins through the intestine wall to reach the systemic circulation is associated with septicemia, renal failure and pulmonary dysfunction. The aim of this work was to investigate bacterial translocation utilizing 99m Tc-E.coli in an experimental model of obstructive jaundice. The levels of bilirubin in rats that were subjected to ligature of the bile duct were significantly increased when compared to control animals (p 99m Tc-E.coli to the mesenteric lymphatic nodules, liver, spleen or lungs of the rats that suffered ligature of the bile duct (p > 0.05). The evaluation of the intestinal permeability using 'per os' administration of 99m Tc-DTPA showed 1.61 ± 0.57% and 1.39 ± 0.72% of radioactivity in the urine of the control and jaundice animals, respectively. The histological analysis of the distal wall of the ileum showed that the covering epithelium and the crypt were morphologically preserved in both groups. The seven-day period after the ligature of the bile duct may not have been long enough to promote modifications in intestinal wall to occur so as to permit the passage of Tc-99m E.coli. (author)

  16. Assessment of bacterial translocation in obstructive jaundice using Tc-99m Escherichia coli

    Directory of Open Access Journals (Sweden)

    Simone Odília Fernandes Diniz

    2005-10-01

    Full Text Available In obstructive jaundice, the passage of bacteria and endotoxins through the intestine wall to reach the systemic circulation is associated with septicemia, renal failure and pulmonary dysfunction. The aim of this work was to investigate bacterial translocation utilizing 99mTc-E.coli in an experimental model of obstructive jaundice. The levels of bilirubin in rats that were subjected to ligature of the bile duct were significantly increased when compared to control animals (p 0.05. The evaluation of the intestinal permeability using "per os" administration of 99mTc-DTPA showed 1.61 ± 0.57% and 1.39 ± 0.72% of radioactivity in the urine of the control and jaundice animals, respectively. The histological analysis of the distal wall of the ileum showed that the covering epithelium and the crypt were morphologically preserved in both groups. The seven-day period after the ligature of the bile duct may not have been long enough to promote modifications in intestinal wall to occur so as to permit the passage of Tc-99m E.coli.Na icterícia obstrutiva, a passagem de bactérias e endotoxinas através da parede intestinal alcançando a circulação sistêmica está associada com septicemia, falência renal e disfunção pulmonar. A proposta deste trabalho foi investigar a translocação bacteriana, empregando a Tc-99m E.coli, em um modelo experimental de icterícia obstrutiva. Os níveis de bilirrubina nos ratos que sofreram a ligadura do ducto biliar estavam significativamente aumentados quando comparados com os valores dos animais controles (p0,05. A avaliação da permeabilidade intestinal usando a administração "per os" de 99mTc-DTPA mostrou um percentual de eliminação deste radiofármaco na urina de 1,61±0,57 e 1,39±0,72 para os animais controles e ictéricos, respectivamente. A análise histológica da parede distal do íleo mostrou que tanto o epitélio de revestimento quanto as criptas apresentaram morfologicamente conservados em ambos os

  17. Enteropathogenic Escherichia coli translocate Tir and form an intimin-Tir intimate attachment to red blood cell membranes.

    Science.gov (United States)

    Shaw, Robert K; Daniell, Sarah; Frankel, Gad; Knutton, Stuart

    2002-05-01

    Type III secretion allows bacteria to inject effector proteins into host cells. In enteropathogenic Escherichia coli (EPEC) the type III secreted protein, Tir, is translocated to the host-cell plasma membrane where it functions as a receptor for the bacterial adhesin intimin, leading to intimate bacterial attachment and "attaching and effacing" (A/E) lesion formation. To study EPEC type III secretion the interaction of EPEC with monolayers of red blood cells (RBCs) has been exploited and in a recent study [Shaw, R. K., Daniell, S., Ebel, F., Frankel, G. & Knutton, S. (2001 ). Cell Microbiol 3, 213-222] it was shown that EPEC induced haemolysis of RBCs and translocation of EspD, a putative pore-forming type III secreted protein in the RBC membrane. Here it is demonstrated that EPEC are able to translocate and correctly insert Tir into the RBC membrane and produce an intimin-Tir intimate bacterial attachment, identical to that seen in A/E lesions. Following translocation Tir did not undergo any change in apparent molecular mass or become tyrosine-phosphorylated and there was no focusing of RBC cytoskeletal actin beneath intimately adherent bacteria, and no pedestal formation. This study, employing an RBC model of infection, has demonstrated that Tir translocation can be separated from host-cell-mediated Tir modifications; the data show that the EPEC type III protein translocation apparatus is sufficient to deliver and correctly insert Tir into host-cell membranes independent of eukaryotic cell functions.

  18. Effect of adenine on bacterial translocation using technetium-99m labeled E. coli in an intestinal obstruction model in rats

    International Nuclear Information System (INIS)

    Ugur Oflaz; Fatma Yurt Lambrecht; Osman Yilmaz; Cetin Pekcetin

    2013-01-01

    This study aims to investigate effects of adenine on bacterial translocation (BT) using 99m Tc-labeled E. coli in an intestinal obstruction rat model. In the study twenty-one rats were used. The rats were divided into three groups according to different feeding patterns. The control group (CG) was fed with a standard chow diet for 7 days. Group A1 and group A2 were fed with adenine supplemented chow diet for 7 days. At the end of the feeding period, after all groups was submitted intestinal obstruction. 99m Tc-E. coli was injected into the rats' terminal ileum under anesthetic. The rats were sacrificed under aseptic conditions at 24th h after the surgery. The uptake of 99m Tc-E. coli was determined in organs such as the liver, mesenteric lymph nodes, spleen and ileum. Group A1 and group A2 results show that the uptake of 99m Tc-E. coli decreased in the blood and organs comparing to the CG. As a result, it was observed that adenine reduced the level of BT when compared with CG. The beneficial effect of adenine on BT in intestinal obstruction was observed. However, further studies are needed to more clearly assess how this benefit can be achieved. (author)

  19. Survival of Salmonella and E.coli O157:H7 in soil and translocation into leek (allium porrum) as influenced by mycorrhizal fungi

    Science.gov (United States)

    A study was conducted to determine the influence of arbuscular mycorrhizal (AM) fungi on survival of Salmonella and E. coli O157:H7 (EHEC) in soil and translocation into leek roots and shoot. AM fungi are naturally-occurring soil symbionts that form mutualistic relationships with most crop plants. ...

  20. Structural basis for TatA oligomerization: an NMR study of Escherichia coli TatA dimeric structure.

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    Full Text Available Many proteins are transported across lipid membranes by protein translocation systems in living cells. The twin-arginine transport (Tat system identified in bacteria and plant chloroplasts is a unique system that transports proteins across membranes in their fully-folded states. Up to date, the detailed molecular mechanism of this process remains largely unclear. The Escherichia coli Tat system consists of three essential transmembrane proteins: TatA, TatB and TatC. Among them, TatB and TatC form a tight complex and function in substrate recognition. The major component TatA contains a single transmembrane helix followed by an amphipathic helix, and is suggested to form the translocation pore via self-oligomerization. Since the TatA oligomer has to accommodate substrate proteins of various sizes and shapes, the process of its assembly stands essential for understanding the translocation mechanism. A structure model of TatA oligomer was recently proposed based on NMR and EPR observations, revealing contacts between the transmembrane helices from adjacent subunits. Herein we report the construction and stabilization of a dimeric TatA, as well as the structure determination by solution NMR spectroscopy. In addition to more extensive inter-subunit contacts between the transmembrane helices, we were also able to observe interactions between neighbouring amphipathic helices. The side-by-side packing of the amphipathic helices extends the solvent-exposed hydrophilic surface of the protein, which might be favourable for interactions with substrate proteins. The dimeric TatA structure offers more detailed information of TatA oligomeric interface and provides new insights on Tat translocation mechanism.

  1. Protein Chaperones Q8ZP25_SALTY from Salmonella Typhimurium and HYAE_ECOLI from Escherichia coli Exhibit Thioredoxin-like Structures Despite Lack of Canonical Thioredoxin Active Site Sequence Motif

    Energy Technology Data Exchange (ETDEWEB)

    Parish, D.; Benach, J; Liu, G; Singarapu, K; Xiao, R; Acton, T; Hunt, J; Montelione, G; Szyperski, T; et. al.

    2008-01-01

    The structure of the 142-residue protein Q8ZP25 SALTY encoded in the genome of Salmonella typhimurium LT2 was determined independently by NMR and X-ray crystallography, and the structure of the 140-residue protein HYAE ECOLI encoded in the genome of Escherichia coli was determined by NMR. The two proteins belong to Pfam (Finn et al. 34:D247-D251, 2006) PF07449, which currently comprises 50 members, and belongs itself to the 'thioredoxin-like clan'. However, protein HYAE ECOLI and the other proteins of Pfam PF07449 do not contain the canonical Cys-X-X-Cys active site sequence motif of thioredoxin. Protein HYAE ECOLI was previously classified as a (NiFe) hydrogenase-1 specific chaperone interacting with the twin-arginine translocation (Tat) signal peptide. The structures presented here exhibit the expected thioredoxin-like fold and support the view that members of Pfam family PF07449 specifically interact with Tat signal peptides.

  2. Protein chaperones Q8ZP25_SALTY from Salmonella typhimurium and HYAE_ECOLI from Escherichia coli exhibit thioredoxin-like structures despite lack of canonical thioredoxin active site sequence motif.

    Science.gov (United States)

    Parish, David; Benach, Jordi; Liu, Goahua; Singarapu, Kiran Kumar; Xiao, Rong; Acton, Thomas; Su, Min; Bansal, Sonal; Prestegard, James H; Hunt, John; Montelione, Gaetano T; Szyperski, Thomas

    2008-12-01

    The structure of the 142-residue protein Q8ZP25_SALTY encoded in the genome of Salmonella typhimurium LT2 was determined independently by NMR and X-ray crystallography, and the structure of the 140-residue protein HYAE_ECOLI encoded in the genome of Escherichia coli was determined by NMR. The two proteins belong to Pfam (Finn et al. 34:D247-D251, 2006) PF07449, which currently comprises 50 members, and belongs itself to the 'thioredoxin-like clan'. However, protein HYAE_ECOLI and the other proteins of Pfam PF07449 do not contain the canonical Cys-X-X-Cys active site sequence motif of thioredoxin. Protein HYAE_ECOLI was previously classified as a [NiFe] hydrogenase-1 specific chaperone interacting with the twin-arginine translocation (Tat) signal peptide. The structures presented here exhibit the expected thioredoxin-like fold and support the view that members of Pfam family PF07449 specifically interact with Tat signal peptides.

  3. Improving Fab' fragment retention in an autonucleolytic Escherichia coli strain by swapping periplasmic nuclease translocation signal from OmpA to DsbA.

    Science.gov (United States)

    Schofield, Desmond M; Sirka, Ernestas; Keshavarz-Moore, Eli; Ward, John M; Nesbeth, Darren N

    2017-12-01

    To reduce unwanted Fab' leakage from an autonucleolytic Escherichia coli strain, which co-expresses OmpA-signalled Staphylococcal nuclease and Fab' fragment in the periplasm, by substituting in Serratial nuclease and the DsbA periplasm translocation signal as alternatives. We attempted to genetically fuse a nuclease from Serratia marcescens to the OmpA signal peptide but plasmid construction failed, possibly due to toxicity of the resultant nuclease. Combining Serratial nuclease to the DsbA signal peptide was successful. The strain co-expressing this nuclease and periplasmic Fab' grew in complex media and exhibited nuclease activity detectable by DNAse agar plate but its growth in defined medium was retarded. Fab' coexpression with Staphylococcal nuclease fused to the DsbA signal peptide resulted in cells exhibiting nuclease activity and growth in defined medium. In cultivation to high cell density in a 5 l bioreactor, DsbA-fused Staphylococcal nuclease co-expression coincided with reduced Fab' leakage relative to the original autonucleolytic Fab' strain with OmpA-fused staphylococcal nuclease. We successfully rescued Fab' leakage back to acceptable levels and established a basis for future investigation of the linkage between periplasmic nuclease expression and leakage of co-expressed periplasmic Fab' fragment to the surrounding growth media.

  4. Three-dimensional structure of Wza, the protein required for translocation of group 1 capsular polysaccharide across the outer membrane of Escherichia coli.

    Science.gov (United States)

    Beis, Konstantinos; Collins, Richard F; Ford, Robert C; Kamis, Alhaji B; Whitfield, Chris; Naismith, James H

    2004-07-02

    Wza is a highly conserved multimeric outer membrane protein complex required for the surface expression of the serotype K30 group 1 capsular polysaccharide in Escherichia coli. Here we present the first three-dimensional structure of this type of polysaccharide exporter at a 15.5-A resolution obtained using single particle averaging on a dataset of cryo-negatively stained protein. Previous structural studies on purified Wza have revealed a homo-oligomeric ring structure that is most probably composed of eight subunits. Symmetry analysis of the three-dimensional structure combined with biochemical two- and three-dimensional crystallographic data strongly suggest that Wza is an octameric complex with a C4 quasi-rotational symmetry and is organized as a tetramer of dimeric subunits. Wza is best described as a stack of two 4-A high rings with differing diameters providing a mushroom-like aspect from the side. The larger ring has a distinctive square shape with a diameter of 115 A, whereas the smaller is almost circular with a diameter of 90 A. In the center of the complex and enclosed by the four symmetrical arms is a small elliptical cagelike cavity of approximately 40 A in diameter. The central cavity is effectively sealed at the top and bottom of the complex but has small inter-arm holes when viewed from the side. We discuss the structure of this complex and implications in the surface translocation of cell-surface polysaccharide.

  5. Prediction of twin-arginine signal peptides

    DEFF Research Database (Denmark)

    Bendtsen, Jannick Dyrløv; Nielsen, Henrik; Widdick, D.

    2005-01-01

    expressions, whereas hydrophobicity discrimination of Tat- and Sec- signal peptides is carried out by an artificial neural network. A potential cleavage site of the predicted Tat signal peptide is also reported. The TatP prediction server is available as a public web server at http://www.cbs.dtu.dk/services/TatP/....

  6. Influence of mycorrhizal fungi on survival of salmonella and E.coli O157:H7 in soil and translocation into allium porrum roots and stem

    Science.gov (United States)

    Modern agriculture disrupts the natural symbiotic relationship arbuscular mycorrhizal (AM) fungi have with most vegetable plants, which may affect translocation of human pathogens into the plant. Five-month-old Allium porrum (leek) plants (with or without AMF [Glomus intraradices]) were used as a m...

  7. Influence of mycorrhizal fungi (glomus intraradices) on survival of Salmonella and E.coli 0157:H7 in soil and translocation into romaine lettuce roots and shoot

    Science.gov (United States)

    Modern agriculture practices disrupt the natural symbiotic relationship that arbuscular mycorrhizal (AM) fungi have with most vegetable plants, which may affect translocation of human pathogens into the plant and/or survival in the soil. AM-fungi are frequently utilized in organic farming to improv...

  8. Local and systemic occurrences of HMGB1 in gnotobiotic piglets infected with E. coli O55 are related to bacterial translocation and inflammatory cytokines

    Czech Academy of Sciences Publication Activity Database

    Šplíchalová, Alla; Šplíchal, Igor

    2012-01-01

    Roč. 60, č. 3 (2012), s. 597-600 ISSN 1043-4666 R&D Projects: GA ČR GA524/09/0365 Institutional support: RVO:61388971 Keywords : HMGB1 * Enteric infection * E. coli Subject RIV: EC - Immunology Impact factor: 2.518, year: 2012

  9. Local and systemic occurrences of HMGB1 in gnotobiotic piglets infected with E.coli 055 are related to bacterial translocation and inflammatory cytokines

    Czech Academy of Sciences Publication Activity Database

    Šplíchalová, Alla; Šplíchal, Igor

    -, č. 66 (2012), s. 65-65 ISSN 0741-5400. [Annual Meeting of The Society for Leukocyte Biology /45./. 28.10.2012-30.10.2012, Maui] R&D Projects: GA ČR GA524/09/0365 Institutional support: RVO:61388971 Keywords : Enteropathogenic * E. coli Subject RIV: EC - Immunology

  10. NCBI nr-aa BLAST: CBRC-XTRO-01-0031 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-XTRO-01-0031 ref|YP_522550.1| Twin-arginine translocation pathway signal [Rhod...oferax ferrireducens T118] gb|ABD69019.1| Twin-arginine translocation pathway signal [Rhodoferax ferrireducens DSM 15236] YP_522550.1 1e-115 73% ...

  11. Scintigraphic visualization of bacterial translocation in experimental strangulated intestinal obstruction

    International Nuclear Information System (INIS)

    Galeev, Yu.M.; Popov, M.V.; Salato, O.V.; Lishmanov, Yu.B.; Grigorev, E.G.; Aparcin, K.A.

    2009-01-01

    The purpose of this study was to obtain scintigraphic images depicting translocation of 99m Tc-labelled Escherichia coli bacteria through the intestinal barrier and to quantify this process using methods of nuclear medicine. Thirty male Wistar rats (including 20 rats with modelled strangulated intestinal obstruction and 10 healthy rats) were used for bacterial scintigraphy. 99m Tc-labelled E. coli bacteria ( 99m Ts-E. coli) with an activity of 7.4-11.1 MBq were administered into a section of the small intestine. Scintigraphic visualization of bacterial translocation into organs and tissues of laboratory animals was recorded in dynamic (240 min) and static (15 min) modes. The number of labelled bacteria, which migrated through the intestinal barrier, was quantified by calculating the translocation index (TI). Control indicated no translocation of 99m Ts-E. coli administered into the intestine through the parietes of the small intestine's distal part in healthy animals. Animals with strangulated obstruction demonstrated different migration strength and routes of labelled bacteria from strangulated and superior to strangulation sections of the small intestine. 99m Ts-E. coli migrated from the strangulated loop into the peritoneal cavity later causing systemic bacteraemia through peritoneal resorption. The section of the small intestine, which was superior to the strangulation, demonstrated migration of labelled bacteria first into the portal and then into the systemic circulation. The strangulated section of the small intestine was the main source of bacteria dissemination since the number of labelled bacteria, which migrated from this section significantly, exceeded that of the area superior to the strangulation section of the small intestine (p = 0.0003). Bacterial scintigraphy demonstrated the possibility of visualizing migration routes of labelled bacteria and quantifying their translocation through the intestinal barrier. This approach to study bacterial

  12. Problem-elephant translocation: translocating the problem and the elephant?

    Directory of Open Access Journals (Sweden)

    Prithiviraj Fernando

    Full Text Available Human-elephant conflict (HEC threatens the survival of endangered Asian elephants (Elephas maximus. Translocating "problem-elephants" is an important HEC mitigation and elephant conservation strategy across elephant range, with hundreds translocated annually. In the first comprehensive assessment of elephant translocation, we monitored 16 translocations in Sri Lanka with GPS collars. All translocated elephants were released into national parks. Two were killed within the parks where they were released, while all the others left those parks. Translocated elephants showed variable responses: "homers" returned to the capture site, "wanderers" ranged widely, and "settlers" established home ranges in new areas soon after release. Translocation caused wider propagation and intensification of HEC, and increased elephant mortality. We conclude that translocation defeats both HEC mitigation and elephant conservation goals.

  13. Simulations of polymer translocation

    NARCIS (Netherlands)

    Vocks, H.

    2008-01-01

    Transport of molecules across membranes is an essential mechanism for life processes. These molecules are often long, and the pores in the membranes are too narrow for the molecules to pass through as a single unit. In such circumstances, the molecules have to squeeze --- i.e., translocate ---

  14. 99mTechnetium labelled Escherichia coli

    International Nuclear Information System (INIS)

    Diniz, S.O.F.; Cardoso, V.N.; Resende, B.M.; Nunan, E.A.; Simal, C.J.R.

    1999-01-01

    Samples of a culture of unlabeled Escherichia coli were incubated with different concentrations of stannous chloride for various time periods. 99m Tc (26.0 MBq) was added to each preparation and the results showed a labelling yield of 98% for E. coli. Since the bacterial viability of 99m Tc-E. coli and E. coli did not show any statistical differences, these results demonstrate that labelling of E. coli with 99m Tc does not modify the bacterial viability, and the radiolabelled bacteria may be a good model to study bacterial translocation

  15. The anti-translocation and anti-inflammatory effect of cinnamon oil in mice with TNBS induced colitis

    Czech Academy of Sciences Publication Activity Database

    Bujňáková, D.; Juhás, Štefan; Faix, Š.

    2013-01-01

    Roč. 68, č. 5 (2013), s. 1000-1003 ISSN 0006-3088 Institutional support: RVO:67985904 Keywords : bacterial translocation * E. coli * colitis * cinnamon oil Subject RIV: CE - Biochemistry Impact factor: 0.696, year: 2013

  16. E. Coli

    Science.gov (United States)

    ... for the bacteria's medical name Escherichia coli . The strange thing about these bacteria — and lots of other ... In some cases, E. coli poisoning can cause life-threatening kidney problems. What Can Kids Do? Adults ...

  17. Abdominal radiation causes bacterial translocation

    International Nuclear Information System (INIS)

    Guzman-Stein, G.; Bonsack, M.; Liberty, J.; Delaney, J.P.

    1989-01-01

    The purpose of this study was to determine if a single dose of radiation to the rat abdomen leads to bacterial translocation into the mesenteric lymph nodes (MLN). A second issue addressed was whether translocation correlates with anatomic damage to the mucosa. The radiated group (1100 cGy) which received anesthesia also was compared with a control group and a third group which received anesthesia alone but no abdominal radiation. Abdominal radiation lead to 100% positive cultures of MLN between 12 hr and 4 days postradiation. Bacterial translocation was almost nonexistent in the control and anesthesia group. Signs of inflammation and ulceration of the intestinal mucosa were not seen until Day 3 postradiation. Mucosal damage was maximal by Day 4. Bacterial translocation onto the MLN after a single dose of abdominal radiation was not apparently dependent on anatomical, histologic damage of the mucosa

  18. Electochemical detection of chromosome translocation

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Dimaki, Maria; Silahtaroglu, Asli

    2014-01-01

    Cytogenetics is a study of the cell structure with a main focus on chromosomes content and their structure. Chromosome abnormalities, such as translocations may cause various genetic disorders and heametological malignancies. Chromosome translocations are structural rearrangements of two...... chromosomes that results in formation of derivative chromosomes with a mixed DNA sequence. The method currently used for their detection is Fluorescent In Situ Hybridization, which requires a use of expensive, fluorescently labeled probes that target the derivative chromosomes. We present here a double...... hybridization approach developed for label-free detection of the chromosome translocations. For specific translocation detection it is necessary to determine that the two DNA sequences forming a derivative chromosome are connected, which is achieved by two subsequent hybridization steps. The electrochemical...

  19. Microscopy of bacterial translocation during small bowel obstruction and ischemia in vivo – a new animal model

    Directory of Open Access Journals (Sweden)

    Hafner Mathias

    2002-08-01

    Full Text Available Abstract Background Existing animal models provide only indirect information about the pathogenesis of infections caused by indigenous gastrointestinal microflora and the kinetics of bacterial translocation. The aim of this study was to develop a novel animal model to assess bacterial translocation and intestinal barrier function in vivo. Methods In anaesthetized male Wistar rats, 0.5 ml of a suspension of green fluorescent protein-transfected E. coli was administered by intraluminal injection in a model of small bowel obstruction. Animals were randomly subjected to non-ischemic or ischemic bowel obstruction. Ischemia was induced by selective clamping of the terminal mesenteric vessels feeding the obstructed bowel loop. Time intervals necessary for translocation of E. coli into the submucosal stroma and the muscularis propria was assessed using intravital microscopy. Results Bacterial translocation into the submucosa and muscularis propria took a mean of 36 ± 8 min and 80 ± 10 min, respectively, in small bowel obstruction. Intestinal ischemia significantly accelerated bacterial translocation into the submucosa (11 ± 5 min, p E. coli were visible in frozen sections of small bowel, mesentery, liver and spleen taken two hours after E. coli administration. Conclusions Intravital microscopy of fluorescent bacteria is a novel approach to study bacterial translocation in vivo. We have applied this technique to define minimal bacterial transit time as a functional parameter of intestinal barrier function.

  20. Bacterial translocation: impact of probiotics

    OpenAIRE

    Jeppsson, Bengt; Mangell, Peter; Adawi, Diya; Molin, Göran

    2004-01-01

    There is a considerable amount of data in humans showing that patients who cannot take in nutrients enterally have more organ failure in the intensive care unit, a less favourable prognosis, and a higher frequency of septicaemia, in particular involving bacterial species from the intestinal tract. However, there is little evidence that this is connected with translocation of bacterial species in humans. Animal data more uniformly imply the existence of such a connection. The main focus of thi...

  1. Suitability of amphibians and reptiles for translocation.

    Science.gov (United States)

    Germano, Jennifer M; Bishop, Phillip J

    2009-02-01

    Translocations are important tools in the field of conservation. Despite increased use over the last few decades, the appropriateness of translocations for amphibians and reptiles has been debated widely over the past 20 years. To provide a comprehensive evaluation of the suitability of amphibians and reptiles for translocation, we reviewed the results of amphibian and reptile translocation projects published between 1991 and 2006. The success rate of amphibian and reptile translocations reported over this period was twice that reported in an earlier review in 1991. Success and failure rates were independent of the taxonomic class (Amphibia or Reptilia) released. Reptile translocations driven by human-wildlife conflict mitigation had a higher failure rate than those motivated by conservation, and more recent projects of reptile translocations had unknown outcomes. The outcomes of amphibian translocations were significantly related to the number of animals released, with projects releasing over 1000 individuals being most successful. The most common reported causes of translocation failure were homing and migration of introduced individuals out of release sites and poor habitat. The increased success of amphibian and reptile translocations reviewed in this study compared with the 1991 review is encouraging for future conservation projects. Nevertheless, more preparation, monitoring, reporting of results, and experimental testing of techniques and reintroduction questions need to occur to improve translocations of amphibians and reptiles as a whole.

  2. Markovian description of unbiased polymer translocation

    International Nuclear Information System (INIS)

    Mondaini, Felipe; Moriconi, L.

    2012-01-01

    We perform, with the help of cloud computing resources, extensive Langevin simulations which provide compelling evidence in favor of a general Markovian framework for unbiased three-dimensional polymer translocation. Our statistical analysis consists of careful evaluations of (i) two-point correlation functions of the translocation coordinate and (ii) the empirical probabilities of complete polymer translocation (taken as a function of the initial number of monomers on a given side of the membrane). We find good agreement with predictions derived from the Markov chain approach recently addressed in the literature by the present authors. -- Highlights: ► We investigate unbiased polymer translocation through membrane pores. ► Large statistical ensembles have been produced with the help of cloud computing resources. ► We evaluate the two-point correlation function of the translocation coordinate. ► We evaluate empirical probabilities for complete polymer translocation. ► Unbiased polymer translocation is described as a Markov stochastic process.

  3. Markovian description of unbiased polymer translocation

    Energy Technology Data Exchange (ETDEWEB)

    Mondaini, Felipe [Instituto de Física, Universidade Federal do Rio de Janeiro, C.P. 68528, 21945-970 Rio de Janeiro, RJ (Brazil); Centro Federal de Educação Tecnológica Celso Suckow da Fonseca, UnED Angra dos Reis, Angra dos Reis, 23953-030, RJ (Brazil); Moriconi, L., E-mail: moriconi@if.ufrj.br [Instituto de Física, Universidade Federal do Rio de Janeiro, C.P. 68528, 21945-970 Rio de Janeiro, RJ (Brazil)

    2012-10-01

    We perform, with the help of cloud computing resources, extensive Langevin simulations which provide compelling evidence in favor of a general Markovian framework for unbiased three-dimensional polymer translocation. Our statistical analysis consists of careful evaluations of (i) two-point correlation functions of the translocation coordinate and (ii) the empirical probabilities of complete polymer translocation (taken as a function of the initial number of monomers on a given side of the membrane). We find good agreement with predictions derived from the Markov chain approach recently addressed in the literature by the present authors. -- Highlights: ► We investigate unbiased polymer translocation through membrane pores. ► Large statistical ensembles have been produced with the help of cloud computing resources. ► We evaluate the two-point correlation function of the translocation coordinate. ► We evaluate empirical probabilities for complete polymer translocation. ► Unbiased polymer translocation is described as a Markov stochastic process.

  4. EFFECT OF POLYMYXIN-B ON INTESTINAL BACTERIAL TRANSLOCATION IN PSEUDOMONAS-AERUGINOSA WOUND-COLONIZED BURNED MICE

    NARCIS (Netherlands)

    DIJKSTRA, HM; MANSON, WL; KLASEN, HJ; VANDERWAAIJ, D

    1992-01-01

    Bacterial translocation (BT) from the gastrointestinal tract has been proposed to play a role in the pathogenesis of septic complications in severely burned patients. In a burn model the effect of a subtherapeutic dose of polymyxin B-sulfate (PB) at BT was examined in Escherichia coli-monoassociated

  5. Multi-perspective smFRET reveals rate-determining late intermediates of ribosomal translocation

    Science.gov (United States)

    Wasserman, Michael R.; Alejo, Jose L.; Altman, Roger B.; Blanchard, Scott C.

    2016-01-01

    Directional translocation of the ribosome through the messenger RNA open reading frame is a critical determinant of translational fidelity. This process entails a complex interplay of large-scale conformational changes within the actively translating particle, which together coordinate the movement of transfer and messenger RNA substrates with respect to the large and small ribosomal subunits. Using pre-steady state, single-molecule fluorescence resonance energy transfer imaging, we have tracked the nature and timing of these conformational events within the Escherichia coli ribosome from five structural perspectives. Our investigations reveal direct evidence of structurally and kinetically distinct, late intermediates during substrate movement, whose resolution is rate-determining to the translocation mechanism. These steps involve intra-molecular events within the EFG(GDP)-bound ribosome, including exaggerated, reversible fluctuations of the small subunit head domain, which ultimately facilitate peptidyl-tRNA’s movement into its final post-translocation position. PMID:26926435

  6. Multiperspective smFRET reveals rate-determining late intermediates of ribosomal translocation.

    Science.gov (United States)

    Wasserman, Michael R; Alejo, Jose L; Altman, Roger B; Blanchard, Scott C

    2016-04-01

    Directional translocation of the ribosome through the mRNA open reading frame is a critical determinant of translational fidelity. This process entails a complex interplay of large-scale conformational changes within the actively translating particle, which together coordinate the movement of tRNA and mRNA substrates with respect to the large and small ribosomal subunits. Using pre-steady state, single-molecule fluorescence resonance energy transfer imaging, we tracked the nature and timing of these conformational events within the Escherichia coli ribosome from five structural perspectives. Our investigations revealed direct evidence of structurally and kinetically distinct late intermediates during substrate movement, whose resolution determines the rate of translocation. These steps involve intramolecular events within the EF-G-GDP-bound ribosome, including exaggerated, reversible fluctuations of the small-subunit head domain, which ultimately facilitate peptidyl-tRNA's movement into its final post-translocation position.

  7. Translocations affecting human immunoglobulin heavy chain locus

    Directory of Open Access Journals (Sweden)

    Sklyar I. V.

    2014-03-01

    Full Text Available Translocations involving human immunoglobulin heavy chain (IGH locus are implicated in different leukaemias and lymphomas, including multiple myeloma, mantle cell lymphoma, Burkitt’s lymphoma and diffuse large B cell lymphoma. We have analysed published data and identified eleven breakpoint cluster regions (bcr related to these cancers within the IgH locus. These ~1 kbp bcrs are specific for one or several types of blood cancer. Our findings could help devise PCR-based assays to detect cancer-related translocations, to identify the mechanisms of translocations and to help in the research of potential translocation partners of the immunoglobulin locus at different stages of B-cell differentiation.

  8. Lactobacillus plantarum L9 but not Lactobacillus acidophilus LA reduces tumour necrosis factor induced bacterial translocation in Caco-2 cells.

    Science.gov (United States)

    Wang, B; Chen, J; Wang, S; Zhao, X; Lu, G; Tang, X

    2017-05-30

    Translocation of bacteria across the intestinal barrier is important in the pathogenesis of systemic sepsis and multiple organ dysfunction syndromes. Inflammatory cytokines increase paracellular permeability that allows increased luminal bacteria to translocate across mucosal epithelium and further deteriorate the gut barrier. In order to reduce this risk, the prophylactic use of probiotics has been recently addressed. In this paper, we investigate the protective role toward tumour necrosis factor (TNF)-α induced non-pathogenic Escherichia coli translocation across Caco-2 monolayers of Lactobacillus strains. According to our experimental data, Lactobacillus plantarum L9 and Lactobacillus acidophilus LA have good capacities to adhere to Caco-2 cells. Addition of L. plantarum L9 and L. acidophilus LA to the enterocyte monolayer surface result in significant inhibition of E. coli adhesion and cell internalisation. However, L. plantarum L9 and L. acidophilus LA did not inhibit the growth of the non-pathogenic E. coli B5 after 24 h incubation. Exposure to TNF-α for 6 h caused a dramatic increase in E. coli B5 translocation across Caco-2 cells, which was uncoupled from increases in paracellular permeability. Pretreatment with L. plantarum L9 prevent TNF-α induced transcellular bacterial translocation and IL-8 production in Caco-2 cells. L. plantarum L9 also did not affect the integrity of the monolayers, as indicated by lactate dehydrogenase release, horseradish peroxidase permeability, and transepithelial electrical resistance. L. plantarum L9 showed the potential to protect enterocytes from an acute inflammatory response and therefore could be good potential prophylactic agents in counteracting bacterial translocation.

  9. Escherichia Coli

    Science.gov (United States)

    Goodsell, David S.

    2009-01-01

    Diverse biological data may be used to create illustrations of molecules in their cellular context. I describe the scientific results that support a recent textbook illustration of an "Escherichia coli cell". The image magnifies a portion of the bacterium at one million times, showing the location and form of individual macromolecules. Results…

  10. DmsD, a Tat system specific chaperone, interacts with other general chaperones and proteins involved in the molybdenum cofactor biosynthesis

    OpenAIRE

    Li, Haiming; Chang, Limei; Howell, Jenika M.; Turner, Raymond J.

    2010-01-01

    Many bacterial oxidoreductases depend on the Tat translocase for correct cell localization. Substrates for the Tat translocase possess twin-arginine leaders. System specific chaperones or redox enzyme maturation proteins (REMPs) are a group of proteins implicated in oxidoreductase maturation. DmsD is a REMP discovered in Escherichia coli, which interacts with the twin-arginine leader sequence of DmsA, the catalytic subunit of DMSO reductase. In this study, we identified several potential inte...

  11. Translocality in Global Software Development

    DEFF Research Database (Denmark)

    Bjørn, Pernille; Søderberg, Anne-Marie; Krishna, S.

    2017-01-01

    . We explored how agile processes in global outsourcing impacts work conditions of the Indian IT developers, and were surprised to find that agile methodologies, even after 3 years of implementation, created a stressful and inflexible work environment negatively impacting their personal lives. Many......What happens when agile methods are introduced in global outsourcing set-ups? Agile methods are designed to empower IT developers in decision-making through self-managing collocated teams. We studied how agile methods were introduced into global outsourcing from the Indian IT vendor’s perspective...... of the negative aspects of work, which agile methodologies were developed to reduce, were evident in the global agile outsourcing set-up. We propose translocality to repudiate the dichotomy of global/local reminding us that methodologies and technologies must be understood as immediately localized and situated...

  12. Hyaluronan synthase mediates dye translocation across liposomal membranes

    Directory of Open Access Journals (Sweden)

    Medina Andria P

    2012-01-01

    Full Text Available Abstract Background Hyaluronan (HA is made at the plasma membrane and secreted into the extracellular medium or matrix by phospolipid-dependent hyaluronan synthase (HAS, which is active as a monomer. Since the mechanism by which HA is translocated across membranes is still unresolved, we assessed the presence of an intraprotein pore within HAS by adding purified Streptococcus equisimilis HAS (SeHAS to liposomes preloaded with the fluorophore Cascade Blue (CB. Results CB translocation (efflux was not observed with mock-purified material from empty vector control E. coli membranes, but was induced by SeHAS, purified from membranes, in a time- and dose-dependent manner. CB efflux was eliminated or greatly reduced when purified SeHAS was first treated under conditions that inhibit enzyme activity: heating, oxidization or cysteine modification with N-ethylmaleimide. Reduced CB efflux also occurred with SeHAS K48E or K48F mutants, in which alteration of K48 within membrane domain 2 causes decreased activity and HA product size. The above results used liposomes containing bovine cardiolipin (BCL. An earlier study testing many synthetic lipids found that the best activating lipid for SeHAS is tetraoleoyl cardiolipin (TO-CL and that, in contrast, tetramyristoyl cardiolipin (TM-CL is an inactivating lipid (Weigel et al, J. Biol. Chem. 281, 36542, 2006. Consistent with the effects of these CL species on SeHAS activity, CB efflux was more than 2-fold greater in liposomes made with TO-CL compared to TM-CL. Conclusions The results indicate the presence of an intraprotein pore in HAS and support a model in which HA is translocated to the exterior by HAS itself.

  13. E. Coli and Pregnancy

    Science.gov (United States)

    ... chat Live Help Fact Sheets Share Escherichia coli (E. coli) Friday, 01 September 2017 In every pregnancy, a ... risk. This sheet talks about whether exposure to E. coli may increase the risk for birth defects over ...

  14. E coli enteritis

    Science.gov (United States)

    ... coli; Food poisoning - E. coli; E. coli diarrhea; Hamburger disease ... coleslaw or potato salad) that have been out of the refrigerator too ... reheated Fish or oysters Raw fruits or vegetables that have ...

  15. Carbon and nitrogen translocation between seagrass ramets

    NARCIS (Netherlands)

    Marbà, N.; Hemminga, M.A.; Mateo, M.A.; Duarte, C.M.; Maas, Y.E.M.; Terrados, J.; Gacia, E.

    2002-01-01

    The spatial scale and the magnitude of carbon and nitrogen translocation was examined in 5 tropical (Cymodocea serrulata, Halophila stipulacea, Halodule uninervis, Thalassodendron ciliatum, Thalassia hemprichii) and 3 temperate (Cymodocea nodosa, Posidonia oceanica, Zostera noltii) seagrass species

  16. Dudleya Variegata Translocation - San Diego [ds654

    Data.gov (United States)

    California Department of Resources — At Mission Trails Regional Park, a translocation project of Dudleya variegata was conducted in efforts to save the population from a private property undergoing...

  17. Ligand binding analyses of the putative peptide transporter YjdL from E. coli display a significant selectivity towards dipeptides

    DEFF Research Database (Denmark)

    Ernst, Heidi Asschenfeldt; Pham, Antony; Hald, Helle

    2009-01-01

    Proton-dependent oligopeptide transporters (POTs) are secondary active transporters that couple the inwards translocation of di- and tripeptides to inwards proton translocation. Escherichia coli contains four genes encoding the putative POT proteins YhiP, YdgR, YjdL and YbgH. We have over-express...

  18. Lactobacillus rhamnosus GG supernatant enhance neonatal resistance to systemic Escherichia coli K1 infection by accelerating development of intestinal defense

    OpenAIRE

    Xiaolong He; Qing Zeng; Santhosh Puthiyakunnon; Zhijie Zeng; Weijun Yang; Jiawen Qiu; Lei Du; Swapna Boddu; Tongwei Wu; Danxian Cai; Sheng-He Huang; Hong Cao

    2017-01-01

    The objective of this study was to determine whether Lactobacillus rhamnosus GG culture supernatant (LCS) has a preventive effect against gut-derived systemic neonatal Escherichia coli (E. coli) K1 infection. The preventive effects were evaluated in human colonic carcinoma cell line Caco-2 and neonatal rat models. Our in vitro results showed that LCS could block adhesion, invasion and translocation of E. coli K1 to Caco-2 monolayer via up-regulating mucin production and maintaining intestinal...

  19. Escherichia coli pathotypes

    Science.gov (United States)

    Escherichia coli strains are important commensals of the intestinal tract of humans and animals; however, pathogenic strains, including diarrhea-inducing E. coli and extraintestinal pathogenic E. coli. Intestinal E. coli pathotypes may cause a dehydrating watery diarrhea, or more severe diseases su...

  20. Stochastic resonance during a polymer translocation process

    International Nuclear Information System (INIS)

    Mondal, Debasish; Muthukumar, M.

    2016-01-01

    We have studied the occurrence of stochastic resonance when a flexible polymer chain undergoes a single-file translocation through a nano-pore separating two spherical cavities, under a time-periodic external driving force. The translocation of the chain is controlled by a free energy barrier determined by chain length, pore length, pore-polymer interaction, and confinement inside the donor and receiver cavities. The external driving force is characterized by a frequency and amplitude. By combining the Fokker-Planck formalism for polymer translocation and a two-state model for stochastic resonance, we have derived analytical formulas for criteria for emergence of stochastic resonance during polymer translocation. We show that no stochastic resonance is possible if the free energy barrier for polymer translocation is purely entropic in nature. The polymer chain exhibits stochastic resonance only in the presence of an energy threshold in terms of polymer-pore interactions. Once stochastic resonance is feasible, the chain entropy controls the optimal synchronization conditions significantly.

  1. Nuclear translocation and retention of growth hormone

    DEFF Research Database (Denmark)

    Mertani, Hichem C; Raccurt, Mireille; Abbate, Aude

    2003-01-01

    We have previously demonstrated that GH is subject to rapid receptor-dependent nuclear translocation. Here, we examine the importance of ligand activation of the GH-receptor (GHR)-associated Janus kinase (JAK) 2 and receptor dimerization for hormone internalization and nuclear translocation by use...... of cells stably transfected with cDNA for the GHR. Staurosporine and herbimycin A treatment of cells did not affect the ability of GH to internalize but resulted in increased nuclear accumulation of hormone. Similarly, receptor mutations, which prevent the association and activation of JAK2, did not affect...... the ability of the hormone to internalize or translocate to the nucleus but resulted in increased nuclear accumulation of GH. These results were observed both by nuclear isolation and confocal laser scanning microscopy. Staurosporine treatment of cells in which human GH (hGH) was targeted to the cytoplasm...

  2. Export of Cytochrome P450 105D1 to the Periplasmic Space of Escherichia coli

    OpenAIRE

    Kaderbhai, Mustak A.; Ugochukwu, Cynthia C.; Kelly, Steven L.; Lamb, David C.

    2001-01-01

    CYP105D1, a cytochrome P450 from Streptomyces griseus, was appended at its amino terminus to the secretory signal of Escherichia coli alkaline phosphatase and placed under the transcriptional control of the native phoA promoter. Heterologous expression in E. coli phosphate-limited medium resulted in abundant synthesis of recombinant CYP105D1 that was translocated across the bacterial inner membrane and processed to yield authentic, heme-incorporated P450 within the periplasmic space. Cell ext...

  3. Translocations used to generate chromosome segment duplications ...

    Indian Academy of Sciences (India)

    a duplication (Dp) of the translocated segment and four inviable (white, W) ascospores with .... of this work, namely, the definition of breakpoint junction sequences of 12 ..... then our results would place supercontig 10.9 in distal. LG VIR. A third ...

  4. Familial cryptic translocation in Angelman syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Weyerts, L.K.; Wiley, J.E.; Loud, K.M. [ECU School of Medicine, Greenville, NC (United States)] [and others

    1994-09-01

    The majority of patients with Angelman syndrome have been shown to have a cytogenetic or molecular deletion on the maternally derived chromosome 15. We report on a case of Angelman syndrome in which this deletion occurs as an unbalanced cryptic translocation involving chromosomes 14 and 15. The proband was diagnosed clinically as having Angelman syndrome. Multiple cytogenetic studies were done without detecting any deletion. When DNA probes (Oncor) specific for the Prader Willi/Angelman locus became available, the patient was restudied and found to be deleted for {open_quotes}region A{close_quotes} (D15S11) but not for {open_quotes}region B{close_quotes} (GABRB3). No other abnormality was detected. The proband`s mother was then studied. The chromosome 15 marker probe and D15S11 were detected on different chromosomes. Using alpha-satellite probes, a cryptic 14;15 translocation was uncovered. This balanced translocation was also found to be carried by the sister of the proband. This case, along with a case presented at the 1993 ASHG meeting, illustrates the need for using acrocentric probes when studying Angelman syndrome patients. The proband was studied using additional probes specific for this region and found to be deleted for SNRPN but not for D15S10. The breakpoint of the translocation in this patient delineates the smallest deletion of the Angelman syndrome region reported to date and therefore may represent the specific gene involved.

  5. Nitrogen uptake and translocation by Chara

    NARCIS (Netherlands)

    Vermeer, C.P.; Escher, M.; Portielje, R.; Klein, de J.J.M.

    2003-01-01

    The potential for above-ground and below-ground uptake and subsequent internal translocation of ammonium (NH4+) and nitrate (NO3-) by the macroalga Chara spp. was investigated. In a two compartment experimental set-up separating above-ground and below-ground algal parts, the charophytes were exposed

  6. 11C-methionine translocation in barley

    International Nuclear Information System (INIS)

    Nakanishi, Hiromi; Bughio, Naimatullah; Shigeta Ishioka, Noriko

    2000-01-01

    11 C-methionine was supplied to barley plants through a single leaf or via the roots and real time 11 C movement was monitored using a PETIS (positron emitting tracer imaging system). In Fe-deficient plants, 11 C-methionine was translocated from the tip of the absorbing leaf to the discrimination center' at the basal part of the shoot and then retranslocated to all the chlorotic leaves, while a negligible amount was retranslocated to the roots. In Fe-sufficient plants, methionine was translocated from the absorbing leaf to the discrimination center and then only to the newest leaf on the main shoot. A negligible amount was also retranslocated to the roots. Although, in Fe-sufficient plants, methionine translocation was observed from absorbing roots to shoots, in Fe-deficient plants, only a little amount was translocated from roots to shoots. In conclusion, methionine from the upper portion of a plant is not used as a precursor of mugineic acid under Fe-deficiency conditions. (author)

  7. Biphasic character of ribosomal translocation and non-Michaelis-Menten kinetics of translation

    Science.gov (United States)

    Xie, Ping

    2014-12-01

    We study theoretically the kinetics of mRNA translocation in the wild-type (WT) Escherichia coli ribosome, which is composed of a small 30 S and large 50 S subunit, and the ribosomes with mutations to some intersubunit bridges such as B1a, B4, B7a, and B8. The theoretical results reproduce well the available in vitro experimental data on the biphasic kinetics of the forward mRNA translocation catalyzed by elongation factor G (EF-G) hydrolyzing GTP, which can be best fit by the sum of two exponentials, and the monophasic kinetics of the spontaneous reverse mRNA translocation in the absence of the elongation factor, which can be best fit by a single-exponential function, in both the WT and mutant ribosomes. We show that both the mutation-induced increase in the maximal rate of the slow phase for the forward mRNA translocation and that in the rate of the spontaneous reverse mRNA translocation result from a reduction in the intrinsic energy barrier to resist the rotational movements between the two subunits, giving the same degree of increase in the two rates. The mutation-induced increase in the maximal rate of the fast phase for the forward mRNA translocation results mainly from the increase in the rate of the ribosomal unlocking, a conformational change in the ribosome that widens the mRNA channel for the mRNA translocation to take place, which could be partly due to the effect of the mutation on the intrasubunit 30S head rotation. Moreover, we study the translation rate of the WT and mutant ribosomes. It is shown that the translation rate versus the concentration of EF-G-GTP does not follow the Michaelis-Menten (MM) kinetics, which is in sharp contrast to the general property of other enzymes that the rate of the enzymatic reaction versus the concentration of a substrate follows the MM kinetics. The physical origin of this non-MM kinetics for the ribosome is revealed.

  8. Characterization of a heavy metal translocating P-type ATPase gene from an environmental heavy metal resistance Enterobacter sp. isolate.

    Science.gov (United States)

    Chien, Chih-Ching; Huang, Chia-Hsuan; Lin, Yi-Wei

    2013-03-01

    Heavy metals are common contaminants found in polluted areas. We have identified a heavy metal translocating P-type ATPase gene (hmtp) via fosmid library and in vitro transposon mutagenesis from an Enterobacter sp. isolate. This gene is believed to participate in the bacterium's heavy metal resistance traits. The complete gene was identified, cloned, and expressed in a suitable Escherichia coli host cell. E. coli W3110, RW3110 (zntA::Km), GG48 (ΔzitB::Cm zntA::Km), and GG51 (ΔzitB::Cm) were used to study the possible effects of this gene for heavy metal (cadmium and zinc in particular) resistance. Among the E. coli strains tested, RW3110 and GG48 showed more sensitivity to cadmium and zinc compared to the wild-type E. coli W3110 and strain GG51. Therefore, strains RW3110 and GG48 were chosen for the reference hosts for further evaluation of the gene's effect. The results showed that expression of this heavy metal translocating P-type ATPase gene could increase the ability for zinc and cadmium resistance in the tested microorganisms.

  9. E. Coli Infections

    Science.gov (United States)

    E. coli is the name of a type of bacteria that lives in your intestines. Most types of E. coli are harmless. However, some types can make you ... type causes travelers' diarrhea. The worst type of E. coli causes bloody diarrhea, and can sometimes cause kidney ...

  10. Stoichiometry and Substrate Affinity of the Mannitol Transporter, EnzymeIImtl, from Escherichia coli

    NARCIS (Netherlands)

    Veldhuis, Gertjan; Broos, Jaap; Poolman, Bert; Scheek, Ruud M.

    2005-01-01

    Uptake and consecutive phosphorylation of mannitol in Escherichia coli is catalyzed by the mannitol permease EnzymeIImtl. The substrate is bound at an extracellular-oriented binding site, translocated to an inward-facing site, from where it is phosphorylated, and subsequently released into the cell.

  11. Distribution of non-LEE-encoded type 3 secretion system dependent effectors in enteropathogenic Escherichia coli

    Directory of Open Access Journals (Sweden)

    Fábia A. Salvador

    2014-09-01

    Full Text Available Enteropathogenic Escherichia coli (EPEC are important human gastroenteritis agents. The prevalence of six non-LEE genes encoding type 3 translocated effectors was investigated. The nleC, cif and nleB genes were more prevalent in typical than in atypical EPEC, although a higher diversity of genes combinations was observed in atypical EPEC.

  12. Induction of transposon TN1 translocation under the action of different mutagens

    International Nuclear Information System (INIS)

    Kubanejshvili, M.G.; Smirnov, S.P.; Tarasov, V.A.

    1983-01-01

    Migration of ampicillin transposon Tn1 under normal conditions in Escherichia coli cells proceeds with low frequency (10 -4 transpositions for cell). The low transposition frequency is conditioned by the transposition repression, realized by the gene-repressor in transposon structure and, probably, by other regulating genes of the bacterium-host. E. coli cell treatment by physical and chemical mutagens resulted in induction of translocation of ampicillin transposon Tn1 from plasmid RP4 into other replicons. Mitomycin C and ultraviolet radiation produced stronger inducing effect as compared to nitroso-guanidine (NG). The effect of the given mutagens on transposition Tn1 correlated with their activating capacity with respect to inducible SOS-functions of E coli. The mutation of rec A didn't influence on spontaneous Tn1 transposition, but blocked completely the induction of transposition process under mutagen effect. The relationship of inducible transposition with SOS-functions in E. coli cells, controlled by recA and lexA genes, as well as the possible role of the process in genetic microorganism variability are discussed in the paper

  13. Translocation heterozygosity in southern African species of Viscum

    Directory of Open Access Journals (Sweden)

    D. Wiens

    1980-11-01

    Full Text Available Sex-associated and floating translocation complexes are characteristic of dioecious species of  Viscum,  but are virtually absent in monoecious species. The majority of dioecious species has fixed sex-associated translocation complexes with the male being the heterozygous sex. The sex-associated multivalent is usually O4 (ring-of-four or O6 , rarely O8 . Dioecious species without sex-associated translocations are much less common. Most of the dioecious species are also polymorphic for floating translocations, producing one or more additional multivalents ranging from O4 to O12. Floating translocations may be more frequent in species that do not have sex-associated translocations. Supernumerary chromosomes are also present in several species. Sex ratios are at unity in most dioecious species, but female-biased ratios may occur in some species. The high correlation between dioecy and translocation heterozygosity suggests that translocations are primarily associated with the origin and establishment of dioecy. Any róle in the maintenance of biased sex ratios through meiotic drive is probably secondary. Sex-associated translocations may serve to stabilize dioecy by bringing the sex factors into close linkage. Subsequent structural rearrangements within a sex-associated translocation complex may bring the sex factors together in one chromosome pair, releasing floating translocations. The high frequencies of floating translocation heterozygosity in some species indicate that such heterozygosity also has adaptive value.

  14. Preimplantation genetic haplotyping a new application for diagnosis of translocation carrier's embryos- preliminary observations of two robertsonian translocation carrier families.

    Science.gov (United States)

    Shamash, Jana; Rienstein, Shlomit; Wolf-Reznik, Haike; Pras, Elon; Dekel, Michal; Litmanovitch, Talia; Brengauz, Masha; Goldman, Boleslav; Yonath, Hagith; Dor, Jehoshua; Levron, Jacob; Aviram-Goldring, Ayala

    2011-01-01

    Preimplantation genetic diagnosis using fluorescence in-situ hybridization (PGD-FISH) is currently the most common reproductive solution for translocation carriers. However, this technique usually does not differentiate between embryos carrying the balanced form of the translocation and those carrying the homologous normal chromosomes. We developed a new application of preimplantation genetic haplotyping (PGH) that can identify and distinguish between all forms of the translocation status in cleavage stage embryos prior to implantation. Polymorphic markers were used to identify and differentiate between the alleles that carry the translocation and those that are the normal homologous chromosomes. Embryos from two families of robertsonian translocation carriers were successfully analyzed using polymorphic markers haplotyping. Our preliminary results indicate that the PGH is capable of distinguishing between normal, balanced and unbalanced translocation carrier embryos. This method will improve PGD and will enable translocation carriers to avoid transmission of the translocation and the associated medical complications to offspring.

  15. The analysis of the defense mechanism against indigenous bacterial translocation in X-irradiated mice

    International Nuclear Information System (INIS)

    Kobayashi, Toshiya; Ohmori, Toshihiro; Yanai, Minoru; Kawanishi, Gosei; Mitsuyama, Masao; Nomoto, Kikuo.

    1991-01-01

    The defense mechanism against indigenous bacterial translocation was studied using a model of endogenous infection in X-irradiated mice. All mice irradiated with 9 Gy died from day 8 to day 15 after irradiation. The death of mice was observed in parallel with the appearance of bacteria from day 7 in various organs, and the causative agent was identified to be Escherichia coli, an indigenous bacterium translocating from the intestine. Decrease in the number of blood leukocytes, peritoneal cells and lymphocytes in Peyer's patches or mesenteric lymph nodes was observed as early as 1 day after irradiation with 6 or 9 Gy. The mitogenic response of lymphocytes from various lymphoid tissues was severely affected as well. The impairment of these parameters for host defense reached the peak 3 days after irradiation and there was no recovery. However, in vivo bacterial activity of Kupffer cells in mice irradiated with 9 Gy was maintained in a normal level for a longer period. It was suggested that Kupffer cells play an important role in the defense against indigenous bacteria translocating from the intenstine in mice. (author)

  16. Obstructive jaundice promotes bacterial translocation in humans.

    Science.gov (United States)

    Kuzu, M A; Kale, I T; Cöl, C; Tekeli, A; Tanik, A; Köksoy, C

    1999-01-01

    Significant bacterial translocation was demonstrated following experimental biliary obstruction, however very little is known about the importance and the prevalence of gut-origin sepsis in obstructive jaundice patients. Therefore, the aim of this study was to investigate the concept of gut-origin sepsis in obstructive jaundiced patients and its clinical importance. Twenty-one patients requiring laparotomy for obstructive jaundice (group I) and thirty patients operated on electively mainly for chronic cholecystitis (group II) were studied. Peritoneal swab, mesenteric lymph node, portal venous blood, liver wedge biopsy and bile were sampled for culture immediately after opening the peritoneum. Additionally, peripheral blood samples were taken pre- and post-operatively from all patients. Post-operatively, patients were monitored for infectious complications. The mean serum bilirubin concentration, gamma glutamyl transferase and alkaline phosphatase levels in jaundiced patients before therapeutic intervention were significantly higher than in control patients. Five patients demonstrated bacterial translocation in group I (24%), whereas only one did so in group II (3.5%, p jaundice significantly promotes bacterial translocation in humans, however, its clinical importance has yet to be defined.

  17. Radiation induced reciprocal translocations and inversions in anopheles albimanus

    International Nuclear Information System (INIS)

    Kaiser, P.E.; Seawright, J.A.; Benedict, M.Q.; Narang, S.

    1982-01-01

    Reciprocal translocations and inversions were induced in Anopheles albimanus Wiedemann by irradiation of males with X rays. A total of 1669 sperm were assayed, and 175 new aberrations were identified as follows: 102 reciprocal translocations (67 autosomal and 35 sex-linked), 45 pericentric inversions, and 28 paracentric inversions. Eleven of the translocations were nearly whole-arm interchanges, and these were selected for the construction of 'capture systems' for compound chromosomes. Two double-heterozygous translocation strains and four homozygous translocation strains were established. Anopheles albimanus females were irradiated, and a pseudolinkage scheme involving mutant markers was employed to identify reciprocal translocations. The irradiation of females was very inefficient; only one translocation was recovered from 1080 ova tested

  18. Financial costs of large carnivore translocations--accounting for conservation.

    Directory of Open Access Journals (Sweden)

    Florian J Weise

    Full Text Available Human-carnivore conflict continues to present a major conservation challenge around the world. Translocation of large carnivores is widely implemented but remains strongly debated, in part because of a lack of cost transparency. We report detailed translocation costs for three large carnivore species in Namibia and across different translocation scenarios. We consider the effect of various parameters and factors on costs and translocation success. Total translocation cost for 30 individuals in 22 events was $80,681 (US Dollars. Median translocation cost per individual was $2,393, and $2,669 per event. Median cost per cheetah was $2,760 (n = 23, and $2,108 per leopard (n = 6. One hyaena was translocated at a cost of $1,672. Tracking technology was the single biggest cost element (56%, followed by captive holding and feeding. Soft releases, prolonged captivity and orphaned individuals also increased case-specific costs. A substantial proportion (65.4% of the total translocation cost was successfully recovered from public interest groups. Less than half the translocations were confirmed successes (44.4%, 3 unknown with a strong species bias. Four leopards (66.7% were successfully translocated but only eight of the 20 cheetahs (40.0% with known outcome met these strict criteria. None of the five habituated cheetahs was translocated successfully, nor was the hyaena. We introduce the concept of Individual Conservation Cost (ICC and define it as the cost of one successfully translocated individual adjusted by costs of unsuccessful events of the same species. The median ICC for cheetah was $6,898 and $3,140 for leopard. Translocations are costly, but we demonstrate that they are not inherently more expensive than other strategies currently employed in non-lethal carnivore conflict management. We conclude that translocation should be one available option for conserving large carnivores, but needs to be critically evaluated on a case-by-case basis.

  19. Financial costs of large carnivore translocations--accounting for conservation.

    Science.gov (United States)

    Weise, Florian J; Stratford, Ken J; van Vuuren, Rudolf J

    2014-01-01

    Human-carnivore conflict continues to present a major conservation challenge around the world. Translocation of large carnivores is widely implemented but remains strongly debated, in part because of a lack of cost transparency. We report detailed translocation costs for three large carnivore species in Namibia and across different translocation scenarios. We consider the effect of various parameters and factors on costs and translocation success. Total translocation cost for 30 individuals in 22 events was $80,681 (US Dollars). Median translocation cost per individual was $2,393, and $2,669 per event. Median cost per cheetah was $2,760 (n = 23), and $2,108 per leopard (n = 6). One hyaena was translocated at a cost of $1,672. Tracking technology was the single biggest cost element (56%), followed by captive holding and feeding. Soft releases, prolonged captivity and orphaned individuals also increased case-specific costs. A substantial proportion (65.4%) of the total translocation cost was successfully recovered from public interest groups. Less than half the translocations were confirmed successes (44.4%, 3 unknown) with a strong species bias. Four leopards (66.7%) were successfully translocated but only eight of the 20 cheetahs (40.0%) with known outcome met these strict criteria. None of the five habituated cheetahs was translocated successfully, nor was the hyaena. We introduce the concept of Individual Conservation Cost (ICC) and define it as the cost of one successfully translocated individual adjusted by costs of unsuccessful events of the same species. The median ICC for cheetah was $6,898 and $3,140 for leopard. Translocations are costly, but we demonstrate that they are not inherently more expensive than other strategies currently employed in non-lethal carnivore conflict management. We conclude that translocation should be one available option for conserving large carnivores, but needs to be critically evaluated on a case-by-case basis.

  20. Measurement of background translocation frequencies in individuals with clones

    Energy Technology Data Exchange (ETDEWEB)

    Wade, Marcelle J. [California State Univ. (CalState), Hayward, CA (United States)

    1996-08-01

    In the leukemia case the unseparated B and T lymphocytes had a high translocation frequency even after 0.0014, respectively. After purging all clones from the data, the translocation frequencies for Bio 8 and Bio 23 were 0.00750.0014 and 0.0073 metaphases were scored for chromosomal aberrations,, specifically reciprocal translocations, using fluorescence in situ hybridization (FISH). Metaphase spreads were used from two healthy, unexposed individuals (not exposed to radiation, chemotherapy or radiotherapy) and one early B- precursor acute lymphocytic leukemia (ALL) patient (metaphase spreads from both separated T lymphocytes and unseparated B and T lymphocytes were scored). All three individuals had an abnormally high translocation frequency. The high translocation frequencies resulted from clonal expansion of specific translocated chromosomes. I show in this thesis that by purging (discounting or removing) clones from the data of unexposed individuals, one can obtain true background translocation frequencies. In two cases, Bio 8 and Bio 23, the measured translocation frequency for chromosomes 1, 2 and 4 was 0.0124 purging all of the clones from the data. This high translocation frequency may be due to a low frequency of some clones and may not be recognized. The separated T lymphocytes had a higher translocation frequency than expected.

  1. ANALISIS CEMARAN BAKTERI Escherichia coli ANALISIS CEMARAN BAKTERI Escherichia coli ANALISIS CEMARAN BAKTERI Escherichia coli

    OpenAIRE

    ANGGREINI, RAHAYU

    2015-01-01

    2015 RAHAYU ANGGREINI coli Penelitian ini bertujuan untuk melakukan identifikasi cemaran bakteri E. coli O157:H7 pada daging sapi di kota Makassar. Sampel pada penelitian ini sebanyak 72 sampel Kata Kunci : Daging sapi, pasar tradisional, E. coli, E. coli O157:H7, kontaminasi bakteri, identifikasi E. coli O157:H7.

  2. Longing Itineraries: Building the Translocal Community

    Directory of Open Access Journals (Sweden)

    Gustavo López Angel

    2017-06-01

    Full Text Available Migration has reshaped social practices, the sense of belonging has been rethought, and the membership is renegotiated and contended; this is why strategies for their sustainability have been generated. The translocal community operates through multilocated relationships that reveal the ways in which migrants are adapting to the new demands of the community. We emphasize the emotional impulse of nostalgia as one of the vehicles of sustainability for the community. The community is redefined and understood in a set of socio-cultural relationships its members generate, and where the locality is not central, but the connection. A new dimension of the social community space is not just the community gathered in a specific place, but also that agreements, commitments, and acknowledgments are exhibited and settled in the cyberspace; this cyberspace gives cohesion and brings a dynamic element to preserve the community, despite the fact that it is even less concrete than the spatial notion of territory. Facebook, YouTube and a blog are the web platforms of the virtual space where "neighbors, compatriots and citizens" (categories of ascription from the migration get together, where there is a reproduction of social practices (even the most ancient and fundamental ones, to give a new dimension to a translocal, multilocated and ciberlocated community.

  3. Another reptile translocation to a national park

    Directory of Open Access Journals (Sweden)

    W.R. Branch

    1990-10-01

    Full Text Available On 4 May 1988 a sub-adult (50 mm snout-vent length, 42 mm tail Jones' girdled lizard Cordylus tropidosternum jonesi was collected in a pile of wood being off-loaded at the new restcamp in the Karoo National Park, Beaufort West. The wood had been transported by lorry from the Kruger National Park. The specimen is deposited in the herpetological collection of the Port Elizabeth Museum (PEM R 4584. Jones' girdled lizard is a small, arboreal cordylid that shelters under tree bark and in hollow logs. It is common and widely-distributed in the Kruger National Park (Pienaar, Haacke & Jacobsen 1983, The Reptiles of the Kruger National Park, 3rd edition. Pretoria: National Parks Board and adjacent lowveld, being replaced in northern Zimbabwe and East Africa by the nominate race. Hewitt & Power (1913, Transactions of the Royal Society of South Africa 3: 147-176, 1913 reported a similar translocation of the species to Kimberley in association with timber brought to the diamond mining camps. One of us noted recently the ease and danger of the unwitting spread of commensal reptile species into conservation areas (Branch 1978, Koedoe 30: 165, and this is confirmed by this additional example. We recommend that should similar shipments of wood be considered essential, then they be fumigated to prevent the translocation of other alien organisms that may potentially have more dangerous consequences.

  4. Arsenic Uptake and Translocation in Plants.

    Science.gov (United States)

    Li, Nannan; Wang, Jingchao; Song, Won-Yong

    2016-01-01

    Arsenic (As) is a highly toxic metalloid that is classified as a non-threshold class-1 carcinogen. Millions of people worldwide suffer from As toxicity due to the intake of As-contaminated drinking water and food. Reducing the As concentration in drinking water and food is thus of critical importance. Phytoremediation of soil contaminated with As and the reduction of As contamination in food depend on a detailed understanding of As uptake and transport in plants. As transporters play essential roles in As uptake, translocation and accumulation in plant cells. In this review, we summarize the current understanding of As transport in plants, with an emphasis on As uptake, mechanisms of As resistance and the long-distance translocation of As, especially the accumulation of As in grains through phloem-mediated transport. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  5. Factors affecting translocation and sclerotial formation in Morchella esculenta

    International Nuclear Information System (INIS)

    Amir, R.; Levanon, D.; Hadar, Y.; Chet, I.

    1995-01-01

    Amir, R., Levanon, D., Hadar, Y., and Chet, I. 1995. Factors affecting translocation and sclerotial formation in Morchella esculenta. Experimental Mycology 19, 61-70. Morchella esculenta was grown on square split plates, forming sclerotia on one side and mycelium on the other. After the fungus ceased to colonize and before sclerotial initials appeared, [ 14 C]3-O-methyl glucose was added to the edge of the plate on the mycelial side. The effect of various activities in the mycelium (source) and sclerotia (sink) on sclerotial formation and translocation were examined using inhibitors and water potential changes of the media. Sodium azide or cycloheximide applied separately to both sides inhibited both sclerotial formation and translocation, showing that processes in the source and sink depend on metabolic activities as well as protein synthesis. The use of nikkomycin inhibited sclerotial formation, without affecting translocation to the sclerotia. Since the hyphal tips swelled and burst, the translocated compounds were lost to the media. In a strain defective in sclerotial formation, used as a control, no translocation took place, showing that there is a connection between sclerotial formation and translocation. Reversal of the water potential gradient between the two media (lower on the mycelial side), reduced the formation of sclerotia and translocation to them. Translocation to Morchella sclerotia takes place via turgor driven mass flow, but is nevertheless affected by activities in both the source and the sink. (author)

  6. Label Free Chromosome Translocation Detection with Silicon nanowires

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Andersen, Karsten Brandt; Frøhling, Kasper Bayer

    HROMOSOME translocation, which is a rearrangement of arms between two chromosomes, is a major group of chromosome abnormalities leading to cancer. As a result, two derivative chromosomes with sequences coming from both chromosomes are formed. The current translocation detection method is a Fluore......HROMOSOME translocation, which is a rearrangement of arms between two chromosomes, is a major group of chromosome abnormalities leading to cancer. As a result, two derivative chromosomes with sequences coming from both chromosomes are formed. The current translocation detection method...

  7. Conjugation in Escherichia coli

    Science.gov (United States)

    Boyer, Herbert

    1966-01-01

    Boyer, Herbert (Yale University, New Haven, Conn.). Conjugation in Escherichia coli. J. Bacteriol. 91:1767–1772. 1966.—The sex factor of Escherichia coli K-12 was introduced into an E. coli B/r strain by circumventing the host-controlled modification and restriction incompatibilities known to exist between these closely related strains. The sexual properties of the constructed F+ B strain and its Hfr derivatives were examined. These studies showed that the E. coli strain B/r F+ and Hfr derivatives are similar to the E. coli strain K-12 F+ and Hfr derivatives. However, the site of sex factor integration was found to be dependent on the host genome. PMID:5327905

  8. Translocation of cell-penetrating peptides into Candida fungal pathogens.

    Science.gov (United States)

    Gong, Zifan; Karlsson, Amy J

    2017-09-01

    Cell-penetrating peptides (CPPs) are small peptides capable of crossing cellular membranes while carrying molecular cargo. Although they have been widely studied for their ability to translocate nucleic acids, small molecules, and proteins into mammalian cells, studies of their interaction with fungal cells are limited. In this work, we evaluated the translocation of eleven fluorescently labeled peptides into the important human fungal pathogens Candida albicans and C. glabrata and explored the mechanisms of translocation. Seven of these peptides (cecropin B, penetratin, pVEC, MAP, SynB, (KFF) 3 K, and MPG) exhibited substantial translocation (>80% of cells) into both species in a concentration-dependent manner, and an additional peptide (TP-10) exhibiting strong translocation into only C. glabrata. Vacuoles were involved in translocation and intracellular trafficking of the peptides in the fungal cells and, for some peptides, escape from the vacuoles and localization in the cytosol were correlated to toxicity toward the fungal cells. Endocytosis was involved in the translocation of cecropin B, MAP, SynB, MPG, (KFF) 3 K, and TP-10, and cecropin B, penetratin, pVEC, and MAP caused membrane permeabilization during translocation. These results indicate the involvement of multiple translocation mechanisms for some CPPs. Although high levels of translocation were typically associated with toxicity of the peptides toward the fungal cells, SynB was translocated efficiently into Candida cells at concentrations that led to minimal toxicity. Our work highlights the potential of CPPs in delivering antifungal molecules and other bioactive cargo to Candida pathogens. © 2017 The Protein Society.

  9. An Updated View of Translocator Protein (TSPO

    Directory of Open Access Journals (Sweden)

    Nunzio Denora

    2017-12-01

    Full Text Available Decades of study on the role of mitochondria in living cells have evidenced the importance of the 18 kDa mitochondrial translocator protein (TSPO, first discovered in the 1977 as an alternative binding site for the benzodiazepine diazepam in the kidneys. This protein participates in a variety of cellular functions, including cholesterol transport, steroid hormone synthesis, mitochondrial respiration, permeability transition pore opening, apoptosis, and cell proliferation. Thus, TSPO has become an extremely attractive subcellular target for the early detection of disease states that involve the overexpression of this protein and the selective mitochondrial drug delivery. This special issue was programmed with the aim of summarizing the latest findings about the role of TSPO in eukaryotic cells and as a potential subcellular target of diagnostics or therapeutics. A total of 9 papers have been accepted for publication in this issue, in particular, 2 reviews and 7 primary data manuscripts, overall describing the main advances in this field.

  10. Delayed reproduction of translocated red-cockaded woodpeckers

    Science.gov (United States)

    James R. McCormick; Richard N. Conner; Daniel Saenz; Brent Burt

    2001-01-01

    Twelve pairs of Red-cockaded Woodpeckers were translocated to the Angelina National Forest from 21 October 1998 to 17 December 1998. Five breeding pairs (consisting of at least one trnnslocated bird) produced eggs/nestlings within the first breeding season after translocation. Clutch initiation dates for all five pairs were later than those of resident breeders. The...

  11. Chromosomal Translocations: Chicken or Egg? | Center for Cancer Research

    Science.gov (United States)

    Many tumor cells have abnormal chromosomes. Some of these abnormalities are caused by chromosomal translocations, which occur when two chromosomes break and incorrectly rejoin, resulting in an exchange of genetic material. Translocations can activate oncogenes, silence tumor suppressor genes, or result in the creation of completely new fusion gene products. While there is

  12. Competition between Sec- and TAT-dependent protein translocation in Escherichia coli

    DEFF Research Database (Denmark)

    Cristóbal, S.; de Gier, J.-W.; Nielsen, Henrik

    1999-01-01

    -routed into the TAT pathway, suggesting that Sec-targeting signals in Lep can override TAT-targeting information in the TorA signal peptide. We also show that the TorA signal peptide can be converted into a Sec-targeting signal peptide by increasing the hydrophobicity of its h-region. Thus, beyond the twin...... the TorA TAT-targeting signal peptide to the Sec-dependent inner membrane protein leader peptidase (Lep). We find that the soluble, periplasmic P2 domain from Lep is re-routed by the TorA signal peptide into the TAT pathway. In contrast, the full-length TorA–Lep fusion protein is not re...

  13. Reconstruction and modeling protein translocation and compartmentalization in Escherichia coli at the genome-scale

    DEFF Research Database (Denmark)

    Liu, Joanne K.; O’Brien, Edward J.; Lerman, Joshua A.

    2014-01-01

    Background: Membranes play a crucial role in cellular functions. Membranes provide a physical barrier, control the trafficking of substances entering and leaving the cell, and are a major determinant of cellular ultra-structure. In addition, components embedded within the membrane participate...... the computation of cellular phenotypes through an integrated computation of proteome composition, abundance, and activity in four cellular compartments (cytoplasm, periplasm, inner and outer membrane). Reconstruction and validation of the model has demonstrated that the iJL1678-ME is capable of capturing...

  14. Translocation of metal phosphate via the phosphate inorganic transport system of Escherichia coli

    NARCIS (Netherlands)

    van Veen, H.W; Abee, T.; Kortstee, G.J J; Konings, W.N; Zehnder, A.J B

    1994-01-01

    P-i transport via the phosphate inorganic transport system (Pit) of Escherichia coil was studied in natural and artificial membranes. P-i uptake via Pit is dependent on the presence of divalent cations, like Mg2+, Ca2+, Co2+, or Mn2+, which form a soluble, neutral metal phosphate (MeHPO(4)) complex.

  15. Multistep Current Signal in Protein Translocation through Graphene Nanopores

    KAUST Repository

    Bonome, Emma Letizia

    2015-05-07

    © 2015 American Chemical Society. In nanopore sensing experiments, the properties of molecules are probed by the variation of ionic currents flowing through the nanopore. In this context, the electronic properties and the single-layer thickness of graphene constitute a major advantage for molecule characterization. Here we analyze the translocation pathway of the thioredoxin protein across a graphene nanopore, and the related ionic currents, by integrating two nonequilibrium molecular dynamics methods with a bioinformatic structural analysis. To obtain a qualitative picture of the translocation process and to identify salient features we performed unsupervised structural clustering on translocation conformations. This allowed us to identify some specific and robust translocation intermediates, characterized by significantly different ionic current flows. We found that the ion current strictly anticorrelates with the amount of pore occupancy by thioredoxin residues, providing a putative explanation of the multilevel current scenario observed in recently published translocation experiments.

  16. Binding and Translocation of Termination Factor Rho Studied at the Single-Molecule Level

    Science.gov (United States)

    Koslover, Daniel J.; Fazal, Furqan M.; Mooney, Rachel A.; Landick, Robert; Block, Steven M.

    2012-01-01

    Rho termination factor is an essential hexameric helicase responsible for terminating 20–50% of all mRNA synthesis in E. coli. We used single- molecule force spectroscopy to investigate Rho-RNA binding interactions at the Rho- utilization (rut) site of the ? tR1 terminator. Our results are consistent with Rho complexes adopting two states, one that binds 57 ±2 nucleotides of RNA across all six of the Rho primary binding sites, and another that binds 85 ±2 nucleotides at the six primary sites plus a single secondary site situated at the center of the hexamer. The single-molecule data serve to establish that Rho translocates 5′-to-3′ towards RNA polymerase (RNAP) by a tethered-tracking mechanism, looping out the intervening RNA between the rut site and RNAP. These findings lead to a general model for Rho binding and translocation, and establish a novel experimental approach that should facilitate additional single- molecule studies of RNA-binding proteins. PMID:22885804

  17. Mechanisms underlying stage-1 TRPL channel translocation in Drosophila photoreceptors.

    Directory of Open Access Journals (Sweden)

    Minh-Ha Lieu

    Full Text Available TRP channels function as key mediators of sensory transduction and other cellular signaling pathways. In Drosophila, TRP and TRPL are the light-activated channels in photoreceptors. While TRP is statically localized in the signaling compartment of the cell (the rhabdomere, TRPL localization is regulated by light. TRPL channels translocate out of the rhabdomere in two distinct stages, returning to the rhabdomere with dark-incubation. Translocation of TRPL channels regulates their availability, and thereby the gain of the signal. Little, however, is known about the mechanisms underlying this trafficking of TRPL channels.We first examine the involvement of de novo protein synthesis in TRPL translocation. We feed flies cycloheximide, verify inhibition of protein synthesis, and test for TRPL translocation in photoreceptors. We find that protein synthesis is not involved in either stage of TRPL translocation out of the rhabdomere, but that re-localization to the rhabdomere from stage-1, but not stage-2, depends on protein synthesis. We also characterize an ex vivo eye preparation that is amenable to biochemical and genetic manipulation. We use this preparation to examine mechanisms of stage-1 TRPL translocation. We find that stage-1 translocation is: induced with ATP depletion, unaltered with perturbation of the actin cytoskeleton or inhibition of endocytosis, and slowed with increased membrane sterol content.Our results indicate that translocation of TRPL out of the rhabdomere is likely due to protein transport, and not degradation/re-synthesis. Re-localization from each stage to the rhabdomere likely involves different strategies. Since TRPL channels can translocate to stage-1 in the absence of ATP, with no major requirement of the cytoskeleton, we suggest that stage-1 translocation involves simple diffusion through the apical membrane, which may be regulated by release of a light-dependent anchor in the rhabdomere.

  18. Enterohemorrhagic Escherichia coli (EHEC

    Directory of Open Access Journals (Sweden)

    Abdullah Kilic

    2011-08-01

    Full Text Available Escherichia coli is a bacterium that is commonly found in the gut of humans and warm-blooded animals. Most strains of E. coli are harmless for human. E. coli O157:H7 is the most common member of a group of pathogenic E. coli strains known variously as enterohaemorrhagic, verocytotoxin-producing, or Shiga-toxin-producing organisms. EHEC bacterium is the major cause of haemorrhagic colitis and haemolytic uraemic syndrome. The reservoir of this pathogen appears to be mainly cattle and other ruminants such as camels. It is transmitted to humans primarily through consumption of contaminated foods. [TAF Prev Med Bull 2011; 10(4.000: 387-388

  19. Can E. coli fly?

    DEFF Research Database (Denmark)

    Lindeberg, Yrja Lisa; Egedal, Karen; Hossain, Zenat Zebin

    2018-01-01

    , and the numbers of flies landing on the exposed rice were counted. Following exposure, the surface of the rice was microbiologically and molecularly analysed for the presence of E. coli and genes of diarrheagenic E. coli and Shigella strains. RESULTS: Rice was at greater risk (p ... with E. coli if flies landed on the rice than if no flies landed on the rice (odds ratio 5·4 (p ...-landings, the average CFU per fly-landing was > 0·6 x 103 CFU. Genes of diarrheagenic E. coli and Shigella species were detected in 39 of 60 (65%) of exposed rice samples. Two fly species were identified; the common housefly (Musca domestica) and the oriental latrine fly (Chrysomya megacephala). CONCLUSION: Flies may...

  20. Minimizing the cost of translocation failure with decision-tree models that predict species' behavioral response in translocation sites.

    Science.gov (United States)

    Ebrahimi, Mehregan; Ebrahimie, Esmaeil; Bull, C Michael

    2015-08-01

    The high number of failures is one reason why translocation is often not recommended. Considering how behavior changes during translocations may improve translocation success. To derive decision-tree models for species' translocation, we used data on the short-term responses of an endangered Australian skink in 5 simulated translocations with different release conditions. We used 4 different decision-tree algorithms (decision tree, decision-tree parallel, decision stump, and random forest) with 4 different criteria (gain ratio, information gain, gini index, and accuracy) to investigate how environmental and behavioral parameters may affect the success of a translocation. We assumed behavioral changes that increased dispersal away from a release site would reduce translocation success. The trees became more complex when we included all behavioral parameters as attributes, but these trees yielded more detailed information about why and how dispersal occurred. According to these complex trees, there were positive associations between some behavioral parameters, such as fight and dispersal, that showed there was a higher chance, for example, of dispersal among lizards that fought than among those that did not fight. Decision trees based on parameters related to release conditions were easier to understand and could be used by managers to make translocation decisions under different circumstances. © 2015 Society for Conservation Biology.

  1. Endogenous E. coli endophthalmitis.

    Science.gov (United States)

    Shammas, H F

    1977-01-01

    A case of Escherichia coli septicemia with associated metastatic en dophthalmitis and endocarditis is presented. The ocular signs and symptoms were the initial manifestations of sepsis. Irreversible damage to the eye occurred in less than 24 hours. The pattern of metastatic bacterial endophthalmitis has changed since the introduction of potent antimicrobial agents, with an increased incidence of Gram-negative bacillemia. E. coli endophthalmitis carries a poor prognosis. Early diagnosis and systemic treatment will prevent the life-threatening complications of sepsis.

  2. Forced Translocation of Polymer through Nanopore: Deterministic Model and Simulations

    Science.gov (United States)

    Wang, Yanqian; Panyukov, Sergey; Liao, Qi; Rubinstein, Michael

    2012-02-01

    We propose a new theoretical model of forced translocation of a polymer chain through a nanopore. We assume that DNA translocation at high fields proceeds too fast for the chain to relax, and thus the chain unravels loop by loop in an almost deterministic way. So the distribution of translocation times of a given monomer is controlled by the initial conformation of the chain (the distribution of its loops). Our model predicts the translocation time of each monomer as an explicit function of initial polymer conformation. We refer to this concept as ``fingerprinting''. The width of the translocation time distribution is determined by the loop distribution in initial conformation as well as by the thermal fluctuations of the polymer chain during the translocation process. We show that the conformational broadening δt of translocation times of m-th monomer δtm^1.5 is stronger than the thermal broadening δtm^1.25 The predictions of our deterministic model were verified by extensive molecular dynamics simulations

  3. [Clinical characteristics and preimplantation genetic diagnosis for male Robertsonian translocations].

    Science.gov (United States)

    Huang, Jin; Lian, Ying; Qiao, Jie; Liu, Ping

    2012-08-18

    To explore the clinical characteristics and the preimplantation genetic diagnosis (PGD) for male Robertsonian translocations. From Jan 2005 to Oct 2011, 96 PGD cycles of 80 male Robertsonian translocations were performed at the Center of Reproductive Medicine of Peking University Third Hospital, Beijing. All the couples were involved in assisted reproductive therapy because of oligozoospermia or repeated abortions. Pregnancy results and clinical characteristics were analyzed in this study. Of all the 80 Robertsonian translocation couples, 62 (77.50%, 62/80) couples suffered from primary infertility due to severe oligoospermia and 8 (10%, 8/80) couples suffered from secondary infertility due to oligoospermia. Moreover, 10 (12.50%, 10/80) couples had recurrent spontaneous abortion. Of all the 80 male Robertsonian translocations, 50 were (13; 14) translocations and 15 (14; 21) translocations. The study showed that 79 PGD cycles had the balanced embryos to transfer and 25 cycles resulted in clinical pregnancies. The clinical pregnancy rate per transfer cycle was 31.65% (25 of 79). Now, 18 couples had 21 viable infants and 3 were ongoing pregnant. Oligozoospermia is the main factor for the infertility of the male Robertsonian translocations. Artificial reproductive techniques can solve their reproductive problems. Moreover, PGD will decrease the risk of recurrent spontaneous abortion and the malformations.

  4. Genetic outcomes from the translocations of the critically endangered woylie

    Directory of Open Access Journals (Sweden)

    Carlo PACIONI, Adrian F.WAYNE, Peter B.S.SPENCER

    2013-06-01

    Full Text Available Translocations are an important conservation strategy for many species. However simply observing demographic growth of a translocated population is not sufficient to infer species recovery. Adequate genetic representation of the source population(s and their long-term viability should also be considered. The woylie Bettongia penicillata ogilbyi has been subject to more formal translocations for conservation than any other marsupial that, up until recently, has resulted in one of the most successful species recoveries in Australia. We used mitochondrial and nuclear DNA markers to assess the genetic outcomes of translocated woylie populations. These populations have lost genetic variability, differentiated from their source population and the supplementation program on two island populations appears to have failed. We discuss the conservation implications that our results have for managing threatened species, outline some general recommendations for the management of present and future translocations and discuss the appropriate sampling design for the establishment of new populations or captive breeding programs that may mitigate the genetic ‘erosion’ seen in our study species. This research provides some practical outcomes and a pragmatic understanding of translocation biology. The findings are directly applicable to other translocation programs [Current Zoology 59 (3: 294-310, 2013].

  5. Mode of ATM-dependent suppression of chromosome translocation

    Energy Technology Data Exchange (ETDEWEB)

    Yamauchi, Motohiro, E-mail: motoyama@nagasaki-u.ac.jp [Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Suzuki, Keiji; Oka, Yasuyoshi; Suzuki, Masatoshi; Kondo, Hisayoshi; Yamashita, Shunichi [Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan)

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer We addressed how ATM suppresses frequency of chromosome translocation. Black-Right-Pointing-Pointer We found ATM/p53-dependent G1 checkpoint suppresses translocation frequency. Black-Right-Pointing-Pointer We found ATM and DNA-PKcs function in a common pathway to suppress translocation. -- Abstract: It is well documented that deficiency in ataxia telangiectasia mutated (ATM) protein leads to elevated frequency of chromosome translocation, however, it remains poorly understood how ATM suppresses translocation frequency. In the present study, we addressed the mechanism of ATM-dependent suppression of translocation frequency. To know frequency of translocation events in a whole genome at once, we performed centromere/telomere FISH and scored dicentric chromosomes, because dicentric and translocation occur with equal frequency and by identical mechanism. By centromere/telomere FISH analysis, we confirmed that chemical inhibition or RNAi-mediated knockdown of ATM causes 2 to 2.5-fold increase in dicentric frequency at first mitosis after 2 Gy of gamma-irradiation in G0/G1. The FISH analysis revealed that ATM/p53-dependent G1 checkpoint suppresses dicentric frequency, since RNAi-mediated knockdown of p53 elevated dicentric frequency by 1.5-fold. We found ATM also suppresses dicentric occurrence independently of its checkpoint role, as ATM inhibitor showed additional effect on dicentric frequency in the context of p53 depletion and Chk1/2 inactivation. Epistasis analysis using chemical inhibitors revealed that ATM kinase functions in the same pathway that requires kinase activity of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to suppress dicentric frequency. From the results in the present study, we conclude that ATM minimizes translocation frequency through its commitment to G1 checkpoint and DNA double-strand break repair pathway that requires kinase activity of DNA-PKcs.

  6. Translocation of threatened plants as a conservation measure in China.

    Science.gov (United States)

    Liu, Hong; Ren, Hai; Liu, Qiang; Wen, XiangYing; Maunder, Michael; Gao, JiangYun

    2015-12-01

    We assessed the current status of plant conservation translocation efforts in China, a topic poorly reported in recent scientific literature. We identified 222 conservation translocation cases involving 154 species, of these 87 were Chinese endemic species and 101 (78%) were listed as threatened on the Chinese Species Red List. We categorized the life form of each species and, when possible, determined for each case the translocation type, propagule source, propagule type, and survival and reproductive parameters. A surprisingly large proportion (26%) of the conservation translocations in China were conservation introductions, largely implemented in response to large-scale habitat destruction caused by the Three-Gorge Dam and another hydropower project. Documentation and management of the translocations varied greatly. Less than half the cases had plant survival records. Statistical analyses showed that survival percentages were significantly correlated with plant life form and the type of planting materials. Thirty percent of the cases had records on whether or not individuals flowered or fruited. Results of information theoretic model selection indicated that plant life form, translocation type, propagule type, propagule source, and time since planting significantly influenced the likelihood of flowering and fruiting on the project level. We suggest that the scientific-based application of species conservation translocations should be promoted as part of a commitment to species recovery management. In addition, we recommend that the common practice of within and out of range introductions in nature reserves to be regulated more carefully due to its potential ecological risks. We recommend the establishment of a national office and database to coordinate conservation translocations in China. Our review effort is timely considering the need for a comprehensive national guideline for the newly announced nation-wide conservation program on species with extremely

  7. Mechanical design of translocating motor proteins.

    Science.gov (United States)

    Hwang, Wonmuk; Lang, Matthew J

    2009-01-01

    Translocating motors generate force and move along a biofilament track to achieve diverse functions including gene transcription, translation, intracellular cargo transport, protein degradation, and muscle contraction. Advances in single molecule manipulation experiments, structural biology, and computational analysis are making it possible to consider common mechanical design principles of these diverse families of motors. Here, we propose a mechanical parts list that include track, energy conversion machinery, and moving parts. Energy is supplied not just by burning of a fuel molecule, but there are other sources or sinks of free energy, by binding and release of a fuel or products, or similarly between the motor and the track. Dynamic conformational changes of the motor domain can be regarded as controlling the flow of free energy to and from the surrounding heat reservoir. Multiple motor domains are organized in distinct ways to achieve motility under imposed physical constraints. Transcending amino acid sequence and structure, physically and functionally similar mechanical parts may have evolved as nature's design strategy for these molecular engines.

  8. [Lactobacillus rhamnosus GG conditioned medium prevents E. coli meningitis by inhibiting nuclear factor-κB pathway].

    Science.gov (United States)

    Zeng, Qing; He, Xiao-Long; Xiao, Han-Sheng; DU, Lei; Li, Yu-Jing; Chen, Le-Cheng; Tian, Hui-Wen; Huang, Sheng-He; Cao, Hong

    2017-01-20

    To investigate whether Lactobacillus rhamnosus GG conditioned medium(LGG-CM)has preventive effect against E. coli K1-induced neuropathogenicity in vitro by inhibiting nuclear factor-κB (NF-κB) signaling pathway. An in vitro blood-brain barrier (BBB) model was constructed using human brain microvascular endothelial cells (HBMECs). The effect of LGG-CM on E. coli-actived NF-κB signaling pathway was assayed using Western blotting. Invasion assay and polymorphonuclear leukocyte (PMN) transmigration assay were performed to explore whether LGG-CM could inhibit E. coli invasion and PMN transmigration across the BBB in vitro. The expressions of ZO-1 and CD44 were detected using Western blotting and immunofluorescence. The changes of trans-epithelial electric resistance (TEER) and bacterial translocation were determined to evaluate the BBB permeability. Pre-treament with LGG-CM inhibited E. coli-activated NF-κB signaling pathway in HBMECs and decreased the invasion of E. coli K1 and transmigration of PMN. Western blotting showed that LGG-CM could alleviate E. coli-induced up-regulation of CD44 and down-regulation of ZO-1 expressions in HBMECs. In addition, pre-treatment with LGG-CM alleviated E. coli K1-induced reduction of TEER and suppressed bacterial translocation across the BBB in vitro. LGG-CM can block E. coli-induced activation of NF-κB signaling pathway and thereby prevents E. coli K1-induced neuropathogenicity by decreasing E. coli K1 invasion rates and PMN transmigration.

  9. Absorption and translocation of phosphorus-32 in guava leaves

    International Nuclear Information System (INIS)

    Natale, William

    1997-01-01

    Phosphorus is easily absorbed by the leaves and translocated. The objective of this work was to evaluate the absorption and translocation of P by guava leaves, with time. When a solution containing 2% MAP and specific activity 0.15 μCi/ml was applied. MAP labelled with 32 P was applied in the 3 rd pair of leaves. These and other leaves, roots and stem were collected separately and analyzed accordingly. The results showed that 20 days after application 12% of the applied P was absorbed by the guava leaves. The translocation of P started immediately after its absorption reaching 20% 2fter 20 days. (author). 19 refs., 4 tabs

  10. Thioredoxin from Escherichia coli

    International Nuclear Information System (INIS)

    Holmgren, A.; Ohlsson, I.; Grankvist, M.L.

    1978-01-01

    A competition radioimmunoassay for Escherichia coli thioredoxin using 125 I-labeled thioredoxin-S 2 and a double antibody technique was developed. The method permits determination of picomole amounts of thioredoxin in crude cell extracts and was used to study the localization of thioredoxin cell fractions. E. coli B was calculated to have approximately 10,000 copies of thioredoxin per cell mainly located in the soluble fraction after separation of the membrane and soluble fractions by gentle lysis and centrifugation. E. coli B tsnC mutants which are defective in the replication of phage T7 DNA in vivo and in vitro were examined for their content of thioredoxin. E. coli B tsnC 7004 contained no detectable level of thioredoxin in cell-free extracts examined under a variety of conditions. The results strongly suggest that tsnC 7004 is a nonsense or deletion mutant. Two other E. coli tsnC mutants, 7007 and 7008, contained detectable levels of thioredoxin in crude extracts as measured by thioredoxin reductase and gave similar immunoprecipitation reactions as the parent strain B/1. By radioimmunoassay incompletely cross-reacting material was present in both strains. These results show that tsnC 7007 and 7008 belong to a type of thioredoxin mutants with missence mutations in the thioredoxin gene affecting the function of thioredoxin as subunit in phage T7 DNA polymerase

  11. An engineered genetic selection for ternary protein complexes inspired by a natural three-component hitchhiker mechanism.

    Science.gov (United States)

    Lee, Hyeon-Cheol; Portnoff, Alyse D; Rocco, Mark A; DeLisa, Matthew P

    2014-12-22

    The bacterial twin-arginine translocation (Tat) pathway is well known to translocate correctly folded monomeric and dimeric proteins across the tightly sealed cytoplasmic membrane. We identified a naturally occurring heterotrimer, the Escherichia coli aldehyde oxidoreductase PaoABC, that is co-translocated by the Tat translocase according to a ternary "hitchhiker" mechanism. Specifically, the PaoB and PaoC subunits, each devoid of export signals, are escorted to the periplasm in a piggyback fashion by the Tat signal peptide-containing subunit PaoA. Moreover, export of PaoA was blocked when either PaoB or PaoC was absent, revealing a surprising interdependence for export that is not seen for classical secretory proteins. Inspired by this observation, we created a bacterial three-hybrid selection system that links the formation of ternary protein complexes with antibiotic resistance. As proof-of-concept, a bispecific antibody was employed as an adaptor that physically crosslinked one antigen fused to a Tat export signal with a second antigen fused to TEM-1 β-lactamase (Bla). The resulting non-covalent heterotrimer was exported in a Tat-dependent manner, delivering Bla to the periplasm where it hydrolyzed β-lactam antibiotics. Collectively, these results highlight the remarkable flexibility of the Tat system and its potential for studying and engineering ternary protein interactions in living bacteria.

  12. BCR translocation to derivative chromosome 2, a new case of chronic myeloid leukemia with complex variant translocation and Philadelphia chromosome

    International Nuclear Information System (INIS)

    Al-Achkar, W.; Wafa, A.; Al-Medani, S.

    2011-01-01

    The well-known typical fusion gene BCR/ABL can be observed in connection with a complex translocation event in only 5-8% of cases with chronic myeloid leukemia (CML). Herein we report an exceptional CML case with complex chromosomal aberrations not observed before, translocated BCR to the derivative chromosome 2 [der(2)], additional to involving a four chromosomes translocation implying chromosomal regions such as 1p32 and 2q21 besides 9q34 and 22q11.2. Which were characterized by molecular cytogenetics. (author)

  13. A case of posttraumatic splenic translocation into the thorax

    International Nuclear Information System (INIS)

    Sosnowski, P.; Sikorski, L.; Ziemianski, A.

    1993-01-01

    A case of the left diaphragmatic hernia due to blunt thoracic and abdominal trauma is presented. Characteristic radiological signs of splenic translocation into the thorax contributed to quick diagnosis and immediate surgical intervention. (author)

  14. Multistep Current Signal in Protein Translocation through Graphene Nanopores

    KAUST Repository

    Bonome, Emma Letizia; Lepore, Rosalba; Raimondo, Domenico; Cecconi, Fabio; Tramontano, Anna; Chinappi, Mauro

    2015-01-01

    of graphene constitute a major advantage for molecule characterization. Here we analyze the translocation pathway of the thioredoxin protein across a graphene nanopore, and the related ionic currents, by integrating two nonequilibrium molecular dynamics

  15. Microbial translocation and cardiometabolic risk factors in HIV infection

    DEFF Research Database (Denmark)

    Trøseid, Marius; Manner, Ingjerd W; Pedersen, Karin K

    2014-01-01

    of microbial translocation are closely associated with several cardiovascular risk factors such as dyslipidemia, insulin resistance, hypertension, coagulation abnormalities, endothelial dysfunction, and carotid atherosclerosis. Future studies should investigate whether associations between microbial...

  16. Carbon translocation in zooanthaellae-coelenterate symbioses

    International Nuclear Information System (INIS)

    Battey, J.F.

    1985-01-01

    When host and algal triglycerides synthesized in the symbiotic sea anemone Condylactis gigantea during light and dark incubations in 14 C-bicarbonate and 14 C-acetate were deacylated, more then 80% of the radioactivity was found in the fatty acid moiety. In contrast, triglycerides isolated from zooxanthellae and host incubated in 14 C-glycerol in the dark were found to have more then 95% of their radioactivity in the glycerol moiety. During 14 C-glycerol incubations in the light, radioactivity in the fatty acid moiety of zooxanthellae triglyceride fatty acid moiety stayed below 5% during 14 C-glycerol incubations in the light. These results show neither the zooxanthellae nor host can rapidly convert glycerol to fatty acid. Radioactivity from 14 C-glycerol that does eventually appear in host lipid may have been respired to 14 CO 2 then photosynthetically fixed by the zooxanthellae and synthesized into lipid fatty acid. The isolated zooxanthellae of C. gigantea contained 3.62 +/- 0.33 mM glycerol, which was 26x the 0.141 +/- 0.02 mM found in the coelenterate tissue. Aposymbiotic coelenterate tissue contained 0.169 +/- 0.05 mM glycerol. The metabolic inhibitors, sodium cyanide, aminooxyacetic acid and cerulenin were used to try and uncouple the production of glycerol by the zooxanthellae from its utilization by the coelenterate host. 10 -5 M NaCN increased the ratio of cross photosynthesis to respiration in both intact tentacles and isolated zooxanthellae, increased translocation from 17.7 +/- 3.5% of total fixed carbon in controls to 43.5 +/- 5.79%, and doubled the amount of photosynthetically fixed carbon accumulating in the coelenterate host over that in controls

  17. Bacterial translocation in clinical intestinal transplantation.

    Science.gov (United States)

    Cicalese, L; Sileri, P; Green, M; Abu-Elmagd, K; Kocoshis, S; Reyes, J

    2001-05-27

    Bacterial translocation (BT) has been suggested to be responsible for the high incidence of infections occurring after small bowel transplantation (SBTx). Bacterial overgrowth, alteration of the mucosal barrier function as a consequence of preservation injury or acute rejection (AR), and potent immunosuppression are all associated with BT. The aim of this study was to evaluate and quantify the correlation of BT with these events. Fifty pediatric SBTx recipients on tacrolimus and prednisone immunosuppression were analyzed. Blood, stool, and liver biopsies and peritoneal fluid were cultured (circa 4000 total specimens) when infection was clinically suspected or as part of follow-up. BT episodes were considered when microorganisms were found simultaneously in blood or liver biopsy and stool. BT (average of 2.0 episodes/patient) was evident in 44% of patients and was most frequently caused by Enterococcus, Staphylococcus, Enterobacter, and Klebsiella. The presence of a colon allograft was associated with a higher rate of BT (75% vs. 33.3%). Furthermore, the transplantation procedure (colon vs. no colon) affected the rate of BT: SBTx=40% vs. 25%, combined liver and SBTx=100% vs. 30%, multivisceral transplantation=25% vs. 50%. AR was associated with 39% of BT episodes. BT followed AR in 9.6% of the cases. In 5.2% of the cases, positive blood cultures without stool confirmation of the bacteria were seen. Prolonged cold ischemia time (CIT) affected BT rate significantly (CIT>9 hr 76% vs. CIT<9 hr 20.8%). This study shows that 1) a substantial percentage of, but not all, BT is associated with AR, 2) the presence of a colon allograft increases the risk for BT, and 3) a long CIT is associated with a high incidence of BT after SBTx.

  18. escherichia coli serotypes confirmed in experimental mammary ...

    African Journals Online (AJOL)

    DJFLEX

    VARIATIONS IN VIRULENCE OF THREE (3) ESCHERICHIA COLI. SEROTYPES CONFIRMED IN ... ows are susceptible to E. coli infection because. E. coli exist in the .... Coli infections in mice: A laboratory animal model for research in.

  19. Meiotic delay of translocation carrying spermatocytes responsible for reduced transmission

    International Nuclear Information System (INIS)

    Buul, P.P.W. van

    1991-01-01

    Using in vivo pulse labelling of spermatocytes from mice irradiated with different doses of X-rays (6 and 7 Gy). The authors demonstrated that cells having translocations derived from irradiated stem cells tend to spend longer time at the meiotic prophase than normal cells. At the 2 Gy level this effect is much less pronounced. The recorded delay forms a good explanation for the reduced transmission of translocations to the next generation observed by others. (author)

  20. Uptake, translocation, and debromination of polybrominated diphenyl ethers in maize

    Institute of Scientific and Technical Information of China (English)

    Moming Zhao; Shuzhen Zhang; Sen Wang; Honglin Huang

    2012-01-01

    Uptake,translocation and debromination of three polybrominated diphenyl ethers(PBDEs),BDE-28,-47 and-99,in maize were studied in a hydroponic experiment.Roots took up most of the PBDEs in the culture solutions and more highly brominated PBDEs had a stronger uptake capability.PBDEs were detected in the stems and leaves of maize after exposure but rarely detected in the blank control plants.Furthermore,PBDE concentrations decreased from roots to stems and then to leaves,and a very clear decreasing gradient was found in segments upwards along the stem.These altogether provide substantiating evidence for the acropetal translocation of PBDEs in maize.More highly brominated PBDEs were translocated with more difficulty.Radial translocation of PBDEs from nodes to sheath inside maize was also observed.Both acropetal and radial translocations were enhanced at higher transpiration rates,suggesting that PBDE transport was probably driven by the transpiration stream.Debromination of PBDEs occurred in all parts of the maize,and debromination patterns of different parent PBDEs and in different parts of a plant were similar but with some differences.This study for the first time provides direct evidence for the acropetal translocation of PBDEs within plants,elucidates the process of PBDE transport and clarifies the debromination products of PBDEs in maize.

  1. The Unexplored Mechanisms and Regulatory Functions of Ribosomal Translocation

    Science.gov (United States)

    Alejo, Jose Luis

    In every cell, protein synthesis is carried out by the ribosome, a complex macromolecular RNA-protein assembly. Decades of structural and kinetic studies have increased our understanding of ribosome initiation, decoding, translocation and termination. Yet, the underlying mechanism of these fundamental processes has yet to be fully delineated. Hence, the molecular basis of regulation remains obscure. Here, single-molecule fluorescence methods are applied to decipher the mechanism and regulatory roles of the multi-step process of directional substrate translocation on the ribosome that accompanies every round of protein synthesis. In Chapter 1, single-molecule fluorescence resonance energy transfer (smFRET) is introduced as a tool for studying bacterial ribosome translocation. Chapter 2 details the experimental methods. In Chapter 3, the elongation factor G(EF-G)-catalyzed movement of substrates through the ribosome is examined from several perspectives or signals reporting on various degrees of freedom of ribosome dynamics. Two ribosomal states interconvert in the presence of EF-G(GDP), displaying novel head domain motions, until relocking takes place. In Chapter 4, in order to test if the mentioned fluctuations leading to relocking are correlated to the engagement of the P-site by the peptidyl-tRNA, the translocation of miscoded tRNAs is studied. Severe defects in the relocking stages of translocation reveal the correlation between this new stage of translocation and P-site tRNA engagement.

  2. Constraining the Lateral Helix of Respiratory Complex I by Cross-linking Does Not Impair Enzyme Activity or Proton Translocation.

    Science.gov (United States)

    Zhu, Shaotong; Vik, Steven B

    2015-08-21

    Complex I (NADH:ubiquinone oxidoreductase) is a multisubunit, membrane-bound enzyme of the respiratory chain. The energy from NADH oxidation in the peripheral region of the enzyme is used to drive proton translocation across the membrane. One of the integral membrane subunits, nuoL in Escherichia coli, has an unusual lateral helix of ∼75 residues that lies parallel to the membrane surface and has been proposed to play a mechanical role as a piston during proton translocation (Efremov, R. G., Baradaran, R., and Sazanov, L. A. (2010) Nature 465, 441-445). To test this hypothesis we have introduced 11 pairs of cysteine residues into Complex I; in each pair one is in the lateral helix, and the other is in a nearby region of subunit N, M, or L. The double mutants were treated with Cu(2+) ions or with bi-functional methanethiosulfonate reagents to catalyze cross-link formation in membrane vesicles. The yields of cross-linked products were typically 50-90%, as judged by immunoblotting, but in no case did the activity of Complex I decrease by >10-20%, as indicated by deamino-NADH oxidase activity or rates of proton translocation. In contrast, several pairs of cysteine residues introduced at other interfaces of N:M and M:L subunits led to significant loss of activity, in particular, in the region of residue Glu-144 of subunit M. The results do not support the hypothesis that the lateral helix of subunit L functions like a piston, but rather, they suggest that conformational changes might be transmitted more directly through the functional residues of the proton translocation apparatus. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Mesenteric microcirculatory dysfunctions and translocation of indigenous bacteria in a rat model of strangulated small bowel obstruction

    Directory of Open Access Journals (Sweden)

    Fernando Luiz Zanoni

    2009-01-01

    Full Text Available PRUPOSE: Bacterial translocation has been shown to occur in critically ill patients after extensive trauma, shock, sepsis, or thermal injury. The present study investigates mesenteric microcirculatory dysfunctions, the bacterial translocation phenomenon, and hemodynamic/metabolic disturbances in a rat model of intestinal obstruction and ischemia. METHODS: Anesthetized (pentobarbital 50 mg/kg, i.p. male Wistar rats (250-350 g were submitted to intestinal obstruction or laparotomy without intestinal obstruction (Sham and were evaluated 24 hours later. Bacterial translocation was assessed by bacterial culture of the mesenteric lymph nodes (MLN, liver, spleen, and blood. Leukocyte-endothelial interactions in the mesenteric microcirculation were assessed by intravital microscopy, and P-selectin and intercellular adhesion molecule (ICAM-1 expressions were quantified by immunohistochemistry. Hematocrit, blood gases, lactate, glucose, white blood cells, serum urea, creatinine, bilirubin, and hepatic enzymes were measured. RESULTS: About 86% of intestinal obstruction rats presented positive cultures for E. coli in samples of the mesenteric lymph nodes, liver, and spleen, and 57% had positive hemocultures. In comparison to the Sham rats, intestinal obstruction induced neutrophilia and increased the number of rolling (~2-fold, adherent (~5-fold, and migrated leukocytes (~11-fold; this increase was accompanied by an increased expression of P-selectin (~2-fold and intercellular adhesion molecule-1 (~2-fold in the mesenteric microcirculation. Intestinal obstruction rats exhibited decreased PaCO2, alkalosis, hyperlactatemia, and hyperglycemia, and increased blood potassium, hepatic enzyme activity, serum urea, creatinine, and bilirubin. A high mortality rate was observed after intestinal obstruction (83% at 72 h vs. 0% in Sham rats. CONCLUSION: Intestinal obstruction and ischemia in rats is a relevant model for the in vivo study of mesenteric microcirculatory

  4. Conflict bear translocation: investigating population genetics and fate of bear translocation in Dachigam National Park, Jammu and Kashmir, India.

    Science.gov (United States)

    Mukesh; Sharma, Lalit Kumar; Charoo, Samina Amin; Sathyakumar, Sambandam

    2015-01-01

    The Asiatic black bear population in Dachigam landscape, Jammu and Kashmir is well recognized as one of the highest density bear populations in India. Increasing incidences of bear-human interactions and the resultant retaliatory killings by locals have become a serious threat to the survivorship of black bears in the Dachigam landscape. The Department of Wildlife Protection in Jammu and Kashmir has been translocating bears involved in conflicts, henceforth 'conflict bears' from different sites in Dachigam landscape to Dachigam National Park as a flagship activity to mitigate conflicts. We undertook this study to investigate the population genetics and the fate of bear translocation in Dachigam National Park. We identified 109 unique genotypes in an area of ca. 650 km2 and observed bear population under panmixia that showed sound genetic variability. Molecular tracking of translocated bears revealed that mostly bears (7 out of 11 bears) returned to their capture sites, possibly due to homing instincts or habituation to the high quality food available in agricultural croplands and orchards, while only four bears remained in Dachigam National Park after translocation. Results indicated that translocation success was most likely to be season dependent as bears translocated during spring and late autumn returned to their capture sites, perhaps due to the scarcity of food inside Dachigam National Park while bears translocated in summer remained in Dachigam National Park due to availability of surplus food resources. Thus, the current management practices of translocating conflict bears, without taking into account spatio-temporal variability of food resources in Dachigam landscape seemed to be ineffective in mitigating conflicts on a long-term basis. However, the study highlighted the importance of molecular tracking of bears to understand their movement patterns and socio-biology in tough terrains like Dachigam landscape.

  5. Conflict bear translocation: investigating population genetics and fate of bear translocation in Dachigam National Park, Jammu and Kashmir, India.

    Directory of Open Access Journals (Sweden)

    Mukesh

    Full Text Available The Asiatic black bear population in Dachigam landscape, Jammu and Kashmir is well recognized as one of the highest density bear populations in India. Increasing incidences of bear-human interactions and the resultant retaliatory killings by locals have become a serious threat to the survivorship of black bears in the Dachigam landscape. The Department of Wildlife Protection in Jammu and Kashmir has been translocating bears involved in conflicts, henceforth 'conflict bears' from different sites in Dachigam landscape to Dachigam National Park as a flagship activity to mitigate conflicts. We undertook this study to investigate the population genetics and the fate of bear translocation in Dachigam National Park. We identified 109 unique genotypes in an area of ca. 650 km2 and observed bear population under panmixia that showed sound genetic variability. Molecular tracking of translocated bears revealed that mostly bears (7 out of 11 bears returned to their capture sites, possibly due to homing instincts or habituation to the high quality food available in agricultural croplands and orchards, while only four bears remained in Dachigam National Park after translocation. Results indicated that translocation success was most likely to be season dependent as bears translocated during spring and late autumn returned to their capture sites, perhaps due to the scarcity of food inside Dachigam National Park while bears translocated in summer remained in Dachigam National Park due to availability of surplus food resources. Thus, the current management practices of translocating conflict bears, without taking into account spatio-temporal variability of food resources in Dachigam landscape seemed to be ineffective in mitigating conflicts on a long-term basis. However, the study highlighted the importance of molecular tracking of bears to understand their movement patterns and socio-biology in tough terrains like Dachigam landscape.

  6. Fate of Escherichia coli O157:H7 (ECOH) in blade tenderized beef prime rib following searing, cooking and holding under commercial conditions

    Science.gov (United States)

    Undercooked non-intact beef has caused a number of illnesses due to contamination with serotype O157:H7 strains of Escherichia coli (ECOH). Few studies have quantified translocation and/or thermal inactivation of ECOH directly in blade tenderized beef. There have been no such studies for prime rib,...

  7. Escherichia coli challenge and one type of smectite alter intestinal barrier of pigs.

    Science.gov (United States)

    Almeida, Juliana Abranches Soares; Liu, Yanhong; Song, Minho; Lee, Jeong Jae; Gaskins, H Rex; Maddox, Carol Wolfgang; Osuna, Orlando; Pettigrew, James Eugene

    2013-12-20

    An experiment was conducted to determine how an E. coli challenge and dietary clays affect the intestinal barrier of pigs. Two groups of 32 pigs (initial BW: 6.9 ± 1.0 kg) were distributed in a 2 × 4 factorial arrangement of a randomized complete block design (2 challenge treatments: sham or E. coli, and 4 dietary treatments: control, 0.3% smectite A, 0.3% smectite B and 0.3% zeolite), with 8 replicates total. Diarrhea score, growth performance, goblet cell size and number, bacterial translocation from intestinal lumen to lymph nodes, intestinal morphology, and relative amounts of sulfo and sialo mucins were measured. The E. coli challenge reduced performance, increased goblet cell size and number in the ileum, increased bacterial translocation from the intestinal lumen to the lymph nodes, and increased ileal crypt depth. One of the clays (smectite A) tended to increase goblet cell size in ileum, which may indicate enhanced protection. In conclusion, E. coli infection degrades intestinal barrier integrity but smectite A may enhance it.

  8. Transcuticular translocation of radionuclides on plant leaf surfaces

    International Nuclear Information System (INIS)

    Matsumoto, Ken-ichi; Watanabe, Tadakazu; Ambe, Shizuko; Yamaguchi, Isamu

    1996-01-01

    The cuticle covering all the outermost surfaces of the aerial parts of plants could play a selective role in uptake and translocation of radionuclides from air into plants. In this study, we investigated the transcuticular uptake and translocation behavior via water droplets of various radionuclides in red clover, orchard grass, Japanese radish and mung bean. Ten μl of an aqueous solution of the multitracer generated from Au was applied to the upper surface of the 2nd leaf of the plants at the 5th leaf stage. The plants were then grown for 14 days at 25degC and 70% RH under illumination of artificial solar lights. The transcuticular uptake and translocation throughout the plant were periodically assayed by determining the radioactivity in the surface residue, the cuticle layer beneath the applied site, the leaf area outside the applied site, the other aerial parts and the root of the plant, using an HPGe detector. The applied radionuclides were absorbed into, in turn, the cuticle layer beneath the applied site and then translocated through the cuticle to the inner tissue and eventually to the other aerial parts and finally to the roots, of the plant. The distribution and accumulation in the plant seems to depend upon the characteristics of each radionuclide and plant species. Ca * and Te * tended to remain on leaf surfaces without being absorbed into the cuticle. On the other hand, Sc * , Co * , Zn * , Se * , Rb * , and Eu * were easily absorbed and translocated to every part of the plant including the root. The other radionuclides such as Be * , Mn * , Sr * , Y * , Ba * , Ce * , Pm * , Gd * , Hf * , Yb * , Lu * , Os * , Ir * , and Pt * remained in the region close to the site of their application. The above results possibly indicate the existence of mechanisms common to these plants for selective transcuticular uptake and translocation of radionuclides within plant tissues, though their translocation was considerably influenced by the plant species. (author)

  9. High-speed detection of DNA translocation in nanopipettes

    Science.gov (United States)

    Fraccari, Raquel L.; Ciccarella, Pietro; Bahrami, Azadeh; Carminati, Marco; Ferrari, Giorgio; Albrecht, Tim

    2016-03-01

    We present a high-speed electrical detection scheme based on a custom-designed CMOS amplifier which allows the analysis of DNA translocation in glass nanopipettes on a microsecond timescale. Translocation of different DNA lengths in KCl electrolyte provides a scaling factor of the DNA translocation time equal to p = 1.22, which is different from values observed previously with nanopipettes in LiCl electrolyte or with nanopores. Based on a theoretical model involving electrophoresis, hydrodynamics and surface friction, we show that the experimentally observed range of p-values may be the result of, or at least be affected by DNA adsorption and friction between the DNA and the substrate surface.We present a high-speed electrical detection scheme based on a custom-designed CMOS amplifier which allows the analysis of DNA translocation in glass nanopipettes on a microsecond timescale. Translocation of different DNA lengths in KCl electrolyte provides a scaling factor of the DNA translocation time equal to p = 1.22, which is different from values observed previously with nanopipettes in LiCl electrolyte or with nanopores. Based on a theoretical model involving electrophoresis, hydrodynamics and surface friction, we show that the experimentally observed range of p-values may be the result of, or at least be affected by DNA adsorption and friction between the DNA and the substrate surface. Electronic supplementary information (ESI) available: Gel electrophoresis confirming lengths and purity of DNA samples, comparison between Axopatch 200B and custom-built setup, comprehensive low-noise amplifier characterization, representative I-V curves of nanopipettes used, typical scatter plots of τ vs. peak amplitude for the four LDNA's used, table of most probable τ values, a comparison between different fitting models for the DNA translocation time distribution, further details on the stochastic numerical simulation of the scaling statistics and the derivation of the extended

  10. Role of non-equilibrium conformations on driven polymer translocation.

    Science.gov (United States)

    Katkar, H H; Muthukumar, M

    2018-01-14

    One of the major theoretical methods in understanding polymer translocation through a nanopore is the Fokker-Planck formalism based on the assumption of quasi-equilibrium of polymer conformations. The criterion for applicability of the quasi-equilibrium approximation for polymer translocation is that the average translocation time per Kuhn segment, ⟨τ⟩/N K , is longer than the relaxation time τ 0 of the polymer. Toward an understanding of conditions that would satisfy this criterion, we have performed coarse-grained three dimensional Langevin dynamics and multi-particle collision dynamics simulations. We have studied the role of initial conformations of a polyelectrolyte chain (which were artificially generated with a flow field) on the kinetics of its translocation across a nanopore under the action of an externally applied transmembrane voltage V (in the absence of the initial flow field). Stretched (out-of-equilibrium) polyelectrolyte chain conformations are deliberately and systematically generated and used as initial conformations in translocation simulations. Independent simulations are performed to study the relaxation behavior of these stretched chains, and a comparison is made between the relaxation time scale and the mean translocation time (⟨τ⟩). For such artificially stretched initial states, ⟨τ⟩/N K polymers including single stranded DNA (ssDNA), double stranded DNA (dsDNA), and synthetic polymers. Even when these data are rescaled assuming a constant effective velocity of translocation, it is found that for flexible (ssDNA and synthetic) polymers with N K Kuhn segments, the condition ⟨τ⟩/N K polymers such as ssDNA, a crossover from quasi-equilibrium to non-equilibrium behavior would occur at N K ∼ O(1000).

  11. Translocation of integron-associated resistance in a natural system: Acquisition of resistance determinants by Inc P and Inc W Plasmids from Salmonella enterica Typhimurium DT104

    DEFF Research Database (Denmark)

    Sandvang, Dorthe; Diggle, M.; Platt, D.J.

    2002-01-01

    to determinate the genetic content. Translocation to R751 and R388 was associated with the loss of the indigenous trimethoprim cassette to both plasmids and also acquisition of sulfonamide resistance by R751 and RP4::Tn7, which indicated movement of the 3' terminus of one or both of the DT104 integrons......Salmonella enterica Typhimurium DT104, 961368, a veterinary field isolate that encodes a chromosomal cluster of resistance genes as well as two integrons, was used to study the mobility of resistance cassettes (aadA2 and pse-1) and nonintegron-associated resistance determinants (chloramphenicol...... and tetracycline). A range of natural plasmids was used as targets for the translocation of resistance. Plasmids that acquired resistance from the DT104 chromosome were segregated by conjugation into Escherichia coli K12. Plasmids R751, R388, and RP4::Tn7 acquired several combinations of resistance determinant...

  12. Sorting genomes by reciprocal translocations, insertions, and deletions.

    Science.gov (United States)

    Qi, Xingqin; Li, Guojun; Li, Shuguang; Xu, Ying

    2010-01-01

    The problem of sorting by reciprocal translocations (abbreviated as SBT) arises from the field of comparative genomics, which is to find a shortest sequence of reciprocal translocations that transforms one genome Pi into another genome Gamma, with the restriction that Pi and Gamma contain the same genes. SBT has been proved to be polynomial-time solvable, and several polynomial algorithms have been developed. In this paper, we show how to extend Bergeron's SBT algorithm to include insertions and deletions, allowing to compare genomes containing different genes. In particular, if the gene set of Pi is a subset (or superset, respectively) of the gene set of Gamma, we present an approximation algorithm for transforming Pi into Gamma by reciprocal translocations and deletions (insertions, respectively), providing a sorting sequence with length at most OPT + 2, where OPT is the minimum number of translocations and deletions (insertions, respectively) needed to transform Pi into Gamma; if Pi and Gamma have different genes but not containing each other, we give a heuristic to transform Pi into Gamma by a shortest sequence of reciprocal translocations, insertions, and deletions, with bounds for the length of the sorting sequence it outputs. At a conceptual level, there is some similarity between our algorithm and the algorithm developed by El Mabrouk which is used to sort two chromosomes with different gene contents by reversals, insertions, and deletions.

  13. A somatic origin of homologous Robertsonian translocations and isochromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, W.P.; Bernasconi, F.; Schinzel, A.A. (Univ. of Zurich (Switzerland)); Basaran, S.; Yueksel-Apak, M. (Univ. of Istanbul (Turkey)); Neri, G. (Universita Cattolica, Rome (Italy)); Serville, F. (Hopital d' Enfants Pellegrin, Bordeaux (France)); Balicek, P.; Haluza, R. (Univ. Hospital of Hradeck Kralove, Hradec Kralove (Czech Republic)); Farah, L.M.S. (Escuola Paulista de Medicina, Sao Paulo (Brazil)) (and others)

    1994-02-01

    One t(14q 14q), three t(15q 15q), two t(21q21q), and two t(22q22q) nonmosaic, apparently balanced, de novo Robertsonian translocation cases were investigated with polymorphic markers to establish the origin of the translocated chromosomes. Four cases had results indicative of an isochromosome: one t(14q14q) case with mild mental retardation and maternal uniparental disomy (UPD) for chromosome 14, one t(15q15q) case with the Prader-Willi syndrome and UPD(15), a phenotypically normal carrier of t(22q22q) with maternal UPD(22), and a phenotypically normal t(21q21q) case of paternal UPD(21). All UPD cases showed complete homozygosity throughout the involved chromosome, which is supportive of a postmeiotic origin. In the remaining four cases, maternal and paternal inheritance of the involved chromosome was found, which unambiguously implies a somatic origin. One t(15q15q) female had a child with a ring chromosome 15, which was also of probable postmeiotic origin as recombination between grandparental haplotypes had occurred prior to ring formation. UPD might be expected to result from de novo Robertsonian translocations of meiotic origin; however, all de novo homologous translocation cases, so far reported, with UPD of chromosomes 14, 15, 21, or 22 have been isochromosomes. These data provide the first direct evidence that nonmosaic Robertsonian translocations, as well as isochromosomes, are commonly the result of a mitotic exchange. 75 refs., 1 fig., 4 tabs.

  14. Electrostatics of polymer translocation events in electrolyte solutions.

    Science.gov (United States)

    Buyukdagli, Sahin; Ala-Nissila, T

    2016-07-07

    We develop an analytical theory that accounts for the image and surface charge interactions between a charged dielectric membrane and a DNA molecule translocating through the membrane. Translocation events through neutral carbon-based membranes are driven by a competition between the repulsive DNA-image-charge interactions and the attractive coupling between the DNA segments on the trans and the cis sides of the membrane. The latter effect is induced by the reduction of the coupling by the dielectric membrane. In strong salt solutions where the repulsive image-charge effects dominate the attractive trans-cis coupling, the DNA molecule encounters a translocation barrier of ≈10 kBT. In dilute electrolytes, the trans-cis coupling takes over image-charge forces and the membrane becomes a metastable attraction point that can trap translocating polymers over long time intervals. This mechanism can be used in translocation experiments in order to control DNA motion by tuning the salt concentration of the solution.

  15. Nonabsorbable Antibiotics Reduce Bacterial and Endotoxin Translocation in Hepatectomised Rats

    Directory of Open Access Journals (Sweden)

    S. K. Kakkos

    1997-01-01

    Full Text Available There is increasing evidence that septic complications, occurring after major hepatectomies, may be caused by gram negative bacteria, translocating from the gut. We investigated in rats, the effect of extended hepatectomy on the structure and morphology of the intestinal mucosa as well as on the translocation of intestinal bacteria and endotoxins. We also examined the effect of nonabsorbable antibiotics on reducing the intestinal flora and consequently the phenomenon of translocation by administering neomycin sulphate and cefazoline. Hepatectomy was found to increase translocation, while administration of nonabsorbable antibiotics decreased it significantly. In addition, hepatectomy increased the aerobic cecal bacterial population, which normalised in the group receiving antibiotics. Among the histological parameters evaluated, villus height demonstrated a significant reduction after hepatectomy, while the number of villi per cm and the number of mitoses per crypt, remained unchanged. Our results indicate that administration of nonabsorbable antibiotics presents a positive effect on bacterial and endotoxin translocation after extended hepatectomy, and this may be related to reduction of colonic bacterial load as an intraluminal effect of antibiotics.

  16. Efficient Extracellular Expression of Phospholipase D in Escherichia Coli with an Optimized Signal Peptide

    Science.gov (United States)

    Yang, Leyun; Xu, Yu; Chen, Yong; Ying, Hanjie

    2018-01-01

    New secretion vectors containing the synthetic signal sequence (OmpA’) was constructed for the secretory production of recombinant proteins in Escherichia coli. The E. coli Phospholipase D structural gene (Accession number:NC_018658) fused to various signal sequence were expressed from the Lac promoter in E. coli Rosetta strains by induction with 0.4mM IPTG at 28°C for 48h. SDS-PaGe analysis of expression and subcellular fractions of recombinant constructs revealed the translocation of Phospholipase D (PLD) not only to the medium but also remained in periplasm of E. coli with OmpA’ signal sequence at the N-terminus of PLD. Thus the study on the effects of various surfactants on PLD extracellular production in Escherichia coli in shake flasks revealed that optimal PLD extracellular production could be achieved by adding 0.4% Triton X-100 into the medium. The maximal extracellular PLD production and extracellular enzyme activity were 0.23mg ml-1 and 16U ml-1, respectively. These results demonstrate the possibility of efficient secretory production of recombinant PLD in E. coli should be a potential industrial applications.

  17. Mechanism for translocation of fluoroquinolones across lipid membranes

    DEFF Research Database (Denmark)

    Cramariuc, O.; Rog, T.; Javanainen, M.

    2012-01-01

    Classical atom-scale molecular dynamics simulations, constrained free energy calculations, and quantum mechanical (QM) calculations are employed to study the diffusive translocation of ciprofloxacin (CPFX) across lipid membranes. CPFX is considered here as a representative of the fluoroquinolone...... antibiotics class. Neutral and zwitterionic CPFX coexist at physiological pH, with the latter being predominant. Simulations reveal that only the neutral form permeates the bilayer, and it does so through a novel mechanism that involves dissolution of concerted stacks of zwitterionic ciprofloxacins....... Subsequent QM analysis of the observed molecular stacking shows the important role of partial charge neutralization in the stacks, highlighting how the zwitterionic form of the drug is neutralized for translocation. The findings propose a translocation mechanism in which zwitterionic CPFX molecules approach...

  18. Biological mechanisms and translocation kinetics of particulate plutonium

    International Nuclear Information System (INIS)

    Bruenger, F.W.; Stevens, W.; Atherton, D.R.; Roswell, R.L.; Smith, J.M.

    1981-01-01

    The dissolution and elimination of particulate 239 Pu from its initial sites of deposition in phagocytic organs (the liver, spleen, and lung), as well as its translocation and redeposition in soft tissue organs and skeleton have been investigated. Beagles were injected intravenously with particulate Pu and sacrificed sequentially at times ranging from 33 to 830 days after injection. Equations that describe the overall retention of Pu in liver, spleen, lung, and bone were calculated. Plutonium mobilized from these organs either re-entered the blood stream and redeposited in the skeleton and liver parenchyma or was excreted. The protracted translocation of Pu to bone surfaces potentially exposes all cells involved in osteogenesis to continuous α-radiation, a situation that could enhance the hazard of developing osteosarcoma. A kinetic model that describes the translocation of Pu from the phagocytic compartments to blood and its subsequent redistribution to bone, liver, and other organs was formulated

  19. Evaluating descriptors for the lateral translocation of membrane proteins.

    Science.gov (United States)

    Domanova, Olga; Borbe, Stefan; Mühlfeld, Stefanie; Becker, Martin; Kubitz, Ralf; Häussinger, Dieter; Berlage, Thomas

    2011-01-01

    Microscopic images of tissue sections are used for diagnosis and monitoring of therapy, by analysis of protein patterns correlating to disease states. Spatial protein distribution is influenced by protein translocation between different membrane compartments and quantified by comparison of microscopic images of biological samples. Cholestatic liver diseases are characterized by translocation of transport proteins, and quantification of their dislocation offers new diagnostic options. However, reliable and unbiased tools are lacking. The nowadays used manual method is slow, subjective and error-prone. We have developed a new workflow based on automated image analysis and improved it by the introduction of scale-free descriptors for the translocation quantification. This fast and unbiased method can substitute the manual analysis, and the suggested descriptors perform better than the earlier used statistical variance.

  20. Crystallographic snapshot of cellulose synthesis and membrane translocation.

    Science.gov (United States)

    Morgan, Jacob L W; Strumillo, Joanna; Zimmer, Jochen

    2013-01-10

    Cellulose, the most abundant biological macromolecule, is an extracellular, linear polymer of glucose molecules. It represents an essential component of plant cell walls but is also found in algae and bacteria. In bacteria, cellulose production frequently correlates with the formation of biofilms, a sessile, multicellular growth form. Cellulose synthesis and transport across the inner bacterial membrane is mediated by a complex of the membrane-integrated catalytic BcsA subunit and the membrane-anchored, periplasmic BcsB protein. Here we present the crystal structure of a complex of BcsA and BcsB from Rhodobacter sphaeroides containing a translocating polysaccharide. The structure of the BcsA-BcsB translocation intermediate reveals the architecture of the cellulose synthase, demonstrates how BcsA forms a cellulose-conducting channel, and suggests a model for the coupling of cellulose synthesis and translocation in which the nascent polysaccharide is extended by one glucose molecule at a time.

  1. PART I. ESCHERICHIA COLI

    Directory of Open Access Journals (Sweden)

    Sanaa Mahdi Oraibi

    2016-11-01

    Full Text Available The presence of Escherichia coli in the air of facilities involved in management and composting of post-slaughter poultry wastes in selected plants of West Western Pomerania region was studied. Measurements were made on four dates in a variety of weather conditions during the year. The study was conducted at 5 objects that differ in the type of waste and the degree of preparation for composting. These were: chemical treatment and preliminary processing plant, liquid wastes reservoir, platform for preparation of materials for composting, storage of biological sediments, and composting facility. Measurement of bacteria count was carried out in accordance with the applicable procedures on selective chromogenic TBX medium. The assays revealed the presence of E. coli at all test objects, but not always on all measurement dates. It has been shown that the presence of E. coli was from 20 to 3047 CFU∙m-3 of air, although the largest quantities were most frequently detected in the air of the building for post-slaughter waste pre-treatment in chemical treatment plant.

  2. Assessment of intestinal permeability and bacterial translocation employing nuclear methods in murine mucositis

    Energy Technology Data Exchange (ETDEWEB)

    Pessoa, Rafaela M.; Takenaka, Isabella K.T.M.; Barros, Patricia A.V.; Moura, Livia P.; Contarini, Sara M.L.; Amorim, Juliana M.; Castilho, Raquel O.; Leite, Camila M.A.; Cardoso, Valbert N.; Diniz, Simone Odilia F. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Mg (Brazil)

    2017-07-01

    Full text: Introduction: Mucositis affects approximately 80% of patients who receive chemotherapy combinations. The lesions are painful, restrict food intake and make patients more susceptible to systemic infections. Some agents and strategies are being studied for controlling mucositis, none of them is used in clinical practice. In Minas Gerais, many studies have addressed the popular use of the plant Arrabidaea chica in the form of tea, to treat intestinal cramps and diarrhea, the main symptoms of mucositis. Objective: To evaluate the potential of Arrabidaea chica extract in the management of the integrity of the intestinal mucosa, using the experimental model of gut mucositis induced by 5-Fluorouracila (5-FU). Methods: The UFMG Ethics Committee for Animal Experimentation (CETEA/UFMG) approved this study (nº 411/2015). Male BALB/c mice between 6-8 weeks of age were randomly divided into four groups (n=9) as follows: 1. Control (CTL) - oral administration of saline solution (10 days); 2. A. chica (AC) - oral administration of A. chica extract (10 days); 3. Mucositis (MUC) - underwent mucositis (5-FU) (10 days); 4. Mucositis + A. chica (MUC+ AC) - underwent mucositis and received oral administration of A. chica extract (10 days). At the 7{sup th} day, mice in the MUC and MUC + AC groups received an intraperitoneal (IP) injection containing 300 mg/kg 5-FU, whereas the animals of the CTL and AC groups received a saline IP injection. After 72 hours (10{sup th} experimental day), intestinal permeability was determined by measuring the radioactivity diffusion in the blood after oral administration of diethylenetriaminepentaacetic acid (DTPA) labelled with technetium-99m ({sup 99m}Tc) and bacterial translocation was determined by measuring the radioactivity diffusion in the blood after oral administration of E. coli labelled with technetium-99m ({sup 99m}Tc). After 4 hours, the mice were euthanized and assessed for intestinal permeability, bacterial translocation and

  3. Assessment of intestinal permeability and bacterial translocation employing nuclear methods in murine mucositis

    International Nuclear Information System (INIS)

    Pessoa, Rafaela M.; Takenaka, Isabella K.T.M.; Barros, Patricia A.V.; Moura, Livia P.; Contarini, Sara M.L.; Amorim, Juliana M.; Castilho, Raquel O.; Leite, Camila M.A.; Cardoso, Valbert N.; Diniz, Simone Odilia F.

    2017-01-01

    Full text: Introduction: Mucositis affects approximately 80% of patients who receive chemotherapy combinations. The lesions are painful, restrict food intake and make patients more susceptible to systemic infections. Some agents and strategies are being studied for controlling mucositis, none of them is used in clinical practice. In Minas Gerais, many studies have addressed the popular use of the plant Arrabidaea chica in the form of tea, to treat intestinal cramps and diarrhea, the main symptoms of mucositis. Objective: To evaluate the potential of Arrabidaea chica extract in the management of the integrity of the intestinal mucosa, using the experimental model of gut mucositis induced by 5-Fluorouracila (5-FU). Methods: The UFMG Ethics Committee for Animal Experimentation (CETEA/UFMG) approved this study (nº 411/2015). Male BALB/c mice between 6-8 weeks of age were randomly divided into four groups (n=9) as follows: 1. Control (CTL) - oral administration of saline solution (10 days); 2. A. chica (AC) - oral administration of A. chica extract (10 days); 3. Mucositis (MUC) - underwent mucositis (5-FU) (10 days); 4. Mucositis + A. chica (MUC+ AC) - underwent mucositis and received oral administration of A. chica extract (10 days). At the 7 th day, mice in the MUC and MUC + AC groups received an intraperitoneal (IP) injection containing 300 mg/kg 5-FU, whereas the animals of the CTL and AC groups received a saline IP injection. After 72 hours (10 th experimental day), intestinal permeability was determined by measuring the radioactivity diffusion in the blood after oral administration of diethylenetriaminepentaacetic acid (DTPA) labelled with technetium-99m ( 99m Tc) and bacterial translocation was determined by measuring the radioactivity diffusion in the blood after oral administration of E. coli labelled with technetium-99m ( 99m Tc). After 4 hours, the mice were euthanized and assessed for intestinal permeability, bacterial translocation and intestinal histology

  4. Experimental and computational studies on the DNA translocation mechanism of the T4 viral packaging motor

    Science.gov (United States)

    Migliori, Amy; Arya, Gaurav; Smith, Douglas E.

    2012-10-01

    Bacteriophage T4 is a double stranded DNA virus that infects E.coli by injecting the viral genome through the cellular wall of a host cell. The T4 genome must be ejected from the viral capsid with sufficient force to ensure infection. To generate high ejection forces, the genome is packaged to high density within the viral capsid. A DNA translocation motor, in which the protein gp17 hydrolyzes ATP and binds to the DNA, is responsible for translocating the genome into the capsid during viral maturation of T4. This motor generates forces in excess of 60 pN and packages DNA at rates exceeding 2000 base pairs/second (bp/s)1. Understanding these small yet powerful motors is important, as they have many potential applications. Though much is known about the activity of these motors from bulk and single molecule biophysical techniques, little is known about their detailed molecular mechanism. Recently, two structures of gp17 have been obtained: a high-resolution X-ray crystallographic structure showing a monomeric compacted form of the enzyme, and a cryo-electron microscopic structure of the extended form of gp17 in complex with actively packaging prohead complexes. Comparison of these two structures indicates several key differences, and a model has been proposed to explain the translocation action of the motor2. Key to this model are a set of residues forming ion pairs across two domains of the gp17 molecule that are proposed to be involved in force generation by causing the collapse of the extended form of gp17. Using a dual optical trap to measure the rates of DNA packaging and the generated forces, we present preliminary mutational data showing that these several of these ion pairs are important to motor function. We have also performed preliminary free energy calculations on the extended and collapsed state of gp17, to confirm that these interdomain ion pairs have large contributions to the change in free energy that occurs upon the collapse of gp17 during the

  5. The Genetics of a Probable Insertional Translocation in SORDARIA BREVICOLLIS.

    Science.gov (United States)

    Bond, D J

    1979-05-01

    A chromosome rearrangement has been isolated and characterized in Sordaria brevicollis. Crosses to spore color mutants on each of the seven linkage groups have enabled the breakpoints to be mapped. The simplest hypothesis to account for the results is that a piece of linkage group VI has been translocated to linkage group V and inserted 2.7 map units from its centromere. Previous reports of markers on this linkage group with centromere distances greater than 2.7 units make it unlikely that the translocation is quasiterminal.

  6. Free energy evaluation in polymer translocation via Jarzynski equality

    Energy Technology Data Exchange (ETDEWEB)

    Mondaini, Felipe, E-mail: fmondaini@if.ufrj.br [Centro Federal de Educação Tecnológica Celso Suckow da Fonseca, Petrópolis, 25.620-003, RJ (Brazil); Moriconi, L., E-mail: moriconi@if.ufrj.br [Instituto de Física, Universidade Federal do Rio de Janeiro, C.P. 68528, 21945-970, Rio de Janeiro, RJ (Brazil)

    2014-05-01

    We perform, with the help of cloud computing resources, extensive Langevin simulations, which provide free energy estimates for unbiased three-dimensional polymer translocation. We employ the Jarzynski equality in its rigorous setting, to compute the variation of the free energy in single monomer translocation events. In our three-dimensional Langevin simulations, the excluded-volume and van der Waals interactions between beads (monomers and membrane atoms) are modeled through a repulsive Lennard-Jones (LJ) potential and consecutive monomers are subject to the Finite-Extension Nonlinear Elastic (FENE) potential. Analysing data for polymers with different lengths, the free energy profile is noted to have interesting finite-size scaling properties.

  7. Free energy evaluation in polymer translocation via Jarzynski equality

    International Nuclear Information System (INIS)

    Mondaini, Felipe; Moriconi, L.

    2014-01-01

    We perform, with the help of cloud computing resources, extensive Langevin simulations, which provide free energy estimates for unbiased three-dimensional polymer translocation. We employ the Jarzynski equality in its rigorous setting, to compute the variation of the free energy in single monomer translocation events. In our three-dimensional Langevin simulations, the excluded-volume and van der Waals interactions between beads (monomers and membrane atoms) are modeled through a repulsive Lennard-Jones (LJ) potential and consecutive monomers are subject to the Finite-Extension Nonlinear Elastic (FENE) potential. Analysing data for polymers with different lengths, the free energy profile is noted to have interesting finite-size scaling properties.

  8. The action spectrum in chloroplast translocation in multilayer leaf cells

    Directory of Open Access Journals (Sweden)

    Zbigniew Lechowski

    2015-01-01

    Full Text Available By measurement of light transmittance through a leaf as criterion of chloroplast translocation, the action spectrum of Ajuga reptans was established. In the spectrum obtained, a correction was introduced for leaf autoabsorption calculated on the basis of the Beer-Lambert law. The action spectrum has two maxima: at λ= 375 nm and λ= 481 nm. The range above 502 nm has no significant effect on chloroplast translocation. Comparison with other objects examined demonstrated that in multilayer leaf cells riboflavin seems also to be a photoreceptor active in this process.

  9. Protein kinase A antagonist inhibits β-catenin nuclear translocation, c-Myc and COX-2 expression and tumor promotion in ApcMin/+ mice

    Directory of Open Access Journals (Sweden)

    Brudvik Kristoffer W

    2011-12-01

    Full Text Available Abstract Background The adenomatous polyposis coli (APC protein is part of the destruction complex controlling proteosomal degradation of β-catenin and limiting its nuclear translocation, which is thought to play a gate-keeping role in colorectal cancer. The destruction complex is inhibited by Wnt-Frz and prostaglandin E2 (PGE2 - PI-3 kinase pathways. Recent reports show that PGE2-induced phosphorylation of β-catenin by protein kinase A (PKA increases nuclear translocation indicating two mechanisms of action of PGE2 on β-catenin homeostasis. Findings Treatment of ApcMin/+ mice that spontaneously develop intestinal adenomas with a PKA antagonist (Rp-8-Br-cAMPS selectively targeting only the latter pathway reduced tumor load, but not the number of adenomas. Immunohistochemical characterization of intestines from treated and control animals revealed that expression of β-catenin, β-catenin nuclear translocation and expression of the β-catenin target genes c-Myc and COX-2 were significantly down-regulated upon Rp-8-Br-cAMPS treatment. Parallel experiments in a human colon cancer cell line (HCT116 revealed that Rp-8-Br-cAMPS blocked PGE2-induced β-catenin phosphorylation and c-Myc upregulation. Conclusion Based on our findings we suggest that PGE2 act through PKA to promote β-catenin nuclear translocation and tumor development in ApcMin/+ mice in vivo, indicating that the direct regulatory effect of PKA on β-catenin nuclear translocation is operative in intestinal cancer.

  10. Organ distribution of radiolabeled enteric Escherichia coli during and after hemorrhagic shock

    International Nuclear Information System (INIS)

    Redan, J.A.; Rush, B.F.; McCullough, J.N.; Machiedo, G.W.; Murphy, T.F.; Dikdan, G.S.; Smith, S.

    1990-01-01

    Translocation of intestinal bacteria to the blood during hemorrhagic shock (HS) has been confirmed in rats and humans. The current study was designed to trace the path of translocated intestinal bacteria in a murine HS model. Thirty-one rats were gavaged with 1,000,000 counts of viable 14C oleic acid-labeled Escherichia coli. Forty-eight hours later the animals were bled to 30 mmHg until either 80% of their maximal shed blood was returned or 5 hours of shock had elapsed and they were resuscitated with Ringer's lactate as previously described. Control animals were cannulated but not shocked. Eight rats immediately after shock and resuscitation, 6 rats 24 hours after shock, 3 rats 48 hours after shock, and 4 animals that died in shock had their heart, lung, liver, spleen, kidney, and serum harvested, cultured, and radioactive content measured. Translocated enteric bacteria are found primarily in the lung immediately after shock with redistribution to the liver and kidney 24 hours later. Animals surviving to 48 hours were capable of eliminating the majority of the bacteria from their major organ systems. Positive cultures for E. coli were also found in the blood, lung, liver, and kidney. We speculate that the inflammatory response stimulated by the bacteria in these organs may contribute to the multiple-organ failure syndrome seen after HS

  11. Pros and cons of characterising an optical translocation setup

    CSIR Research Space (South Africa)

    Maphanga, Charles

    2017-02-01

    Full Text Available an optical translocation setup Charles Maphanga 1, 2 , Rudzani Malabi 1, 2 , Saturnin Ombinda-Lemboumba 1 , Malik Maaza 2 , Patience Mthunzi-Kufa 1, 2* 1 Council for Scientific and Industrial Research, National Laser Centre, P O BOX 395, Pretoria...

  12. Centrifugally driven microfluidic disc for detection of chromosomal translocations

    DEFF Research Database (Denmark)

    Brøgger, Anna Line; Kwasny, Dorota; Bosco, Filippo G.

    2012-01-01

    and prognosis of patients. In this work we demonstrate a novel, centrifugally-driven microfluidic system for controlled manipulation of oligonucleotides and subsequent detection of chromosomal translocations. The device is fabricated in the form of a disc with capillary burst microvalves employed to control...

  13. 40 CFR 798.5460 - Rodent heritable translocation assays.

    Science.gov (United States)

    2010-07-01

    ... fertile animals for cytological confirmation as translocation heterozygotes. (3) Animal selection—(i... administration include oral, inhalation, admixture with food or water, and IP or IV injection. (e) Test.... Criteria for determining normal and semisterile males are usually established for each new strain because...

  14. Polymer translocation through a nanopore: a showcase of anomalous diffusion.

    Science.gov (United States)

    Milchev, A; Dubbeldam, Johan L A; Rostiashvili, Vakhtang G; Vilgis, Thomas A

    2009-04-01

    We investigate the translocation dynamics of a polymer chain threaded through a membrane nanopore by a chemical potential gradient that acts on the chain segments inside the pore. By means of diverse methods (scaling theory, fractional calculus, and Monte Carlo and molecular dynamics simulations), we demonstrate that the relevant dynamic variable, the transported number of polymer segments, s(t), displays an anomalous diffusive behavior, both with and without an external driving force being present. We show that in the absence of drag force the time tau, needed for a macromolecule of length N to thread from the cis into the trans side of a cell membrane, scales as tauN(2/alpha) with the chain length. The anomalous dynamics of the translocation process is governed by a universal exponent alpha= 2/(2nu + 2 - gamma(1)), which contains the basic universal exponents of polymer physics, nu (the Flory exponent) and gamma(1) (the surface entropic exponent). A closed analytic expression for the probability to find s translocated segments at time t in terms of chain length N and applied drag force f is derived from the fractional Fokker-Planck equation, and shown to provide analytic results for the time variation of the statistical moments and . It turns out that the average translocation time scales as tau proportional, f(-1)N(2/alpha-1). These results are tested and found to be in perfect agreement with extensive Monte Carlo and molecular dynamics computer simulations.

  15. Selective bowel decontamination results in gram-positive translocation.

    Science.gov (United States)

    Jackson, R J; Smith, S D; Rowe, M I

    1990-05-01

    Colonization by enteric gram-negative bacteria with subsequent translocation is believed to be a major mechanism for infection in the critically ill patient. Selective bowel decontamination (SBD) has been used to control gram-negative infections by eliminating these potentially pathogenic bacteria while preserving anaerobic and other less pathogenic organisms. Infection with gram-positive organisms and anaerobes in two multivisceral transplant patients during SBD led us to investigate the effect of SBD on gut colonization and translocation. Twenty-four rats received enteral polymixin E, tobramycin, amphotericin B, and parenteral cefotaxime for 7 days (PTA + CEF); 23 received parenteral cefotaxime alone (CEF), 19 received the enteral antibiotics alone (PTA), 21 controls received no antibiotics. Cecal homogenates, mesenteric lymph node (MLN), liver, and spleen were cultured. Only 8% of the PTA + CEF group had gram-negative bacteria in cecal culture vs 52% CEF, 84% PTA, and 100% in controls. Log Enterococcal colony counts were higher in the PTA + CEF group (8.0 + 0.9) vs controls (5.4 + 0.4) P less than 0.01. Translocation of Enterococcus to the MLN was significantly increased in the PTA + CEF group (67%) vs controls (0%) P less than 0.01. SBD effectively eliminates gram-negative organisms from the gut in the rat model. Overgrowth and translocation of Enterococcus suggests that infection with gram-positive organisms may be a limitation of SBD.

  16. Toponomics method for the automated quantification of membrane protein translocation.

    Science.gov (United States)

    Domanova, Olga; Borbe, Stefan; Mühlfeld, Stefanie; Becker, Martin; Kubitz, Ralf; Häussinger, Dieter; Berlage, Thomas

    2011-09-19

    Intra-cellular and inter-cellular protein translocation can be observed by microscopic imaging of tissue sections prepared immunohistochemically. A manual densitometric analysis is time-consuming, subjective and error-prone. An automated quantification is faster, more reproducible, and should yield results comparable to manual evaluation. The automated method presented here was developed on rat liver tissue sections to study the translocation of bile salt transport proteins in hepatocytes. For validation, the cholestatic liver state was compared to the normal biological state. An automated quantification method was developed to analyze the translocation of membrane proteins and evaluated in comparison to an established manual method. Firstly, regions of interest (membrane fragments) are identified in confocal microscopy images. Further, densitometric intensity profiles are extracted orthogonally to membrane fragments, following the direction from the plasma membrane to cytoplasm. Finally, several different quantitative descriptors were derived from the densitometric profiles and were compared regarding their statistical significance with respect to the transport protein distribution. Stable performance, robustness and reproducibility were tested using several independent experimental datasets. A fully automated workflow for the information extraction and statistical evaluation has been developed and produces robust results. New descriptors for the intensity distribution profiles were found to be more discriminative, i.e. more significant, than those used in previous research publications for the translocation quantification. The slow manual calculation can be substituted by the fast and unbiased automated method.

  17. Bladder calculus resulting from an intravesical translocation of ...

    African Journals Online (AJOL)

    Although perforation of the uterus by an intrauterine contraceptive device (IUCD) is commonly encountered, intravesical translocation and secondary calculus formation is a very rare complication.We report a case of a 60-year old multiparous woman in whom an intrauterine contraceptive Copper-T device inserted 12 years ...

  18. Diphtheria toxin translocation across cellular membranes is regulated by sphingolipids

    International Nuclear Information System (INIS)

    Spilsberg, Bjorn; Hanada, Kentaro; Sandvig, Kirsten

    2005-01-01

    Diphtheria toxin is translocated across cellular membranes when receptor-bound toxin is exposed to low pH. To study the role of sphingolipids for toxin translocation, both a mutant cell line lacking the first enzyme in de novo sphingolipid synthesis, serine palmitoyltransferase, and a specific inhibitor of the same enzyme, myriocin, were used. The serine palmitoyltransferase-deficient cell line (LY-B) was found to be 10-15 times more sensitive to diphtheria toxin than the genetically complemented cell line (LY-B/cLCB1) and the wild-type cell line (CHO-K1), both when toxin translocation directly across the plasma membrane was induced by exposing cells with surface-bound toxin to low pH, and when the toxin followed its normal route via acidified endosomes into the cytosol. Toxin binding was similar in these three cell lines. Furthermore, inhibition of serine palmitoyltransferase activity by addition of myriocin sensitized the two control cell lines (LY-B/cLCB1 and CHO-K1) to diphtheria toxin, whereas, as expected, no effect was observed in cells lacking serine palmitoyltransferase (LY-B). In conclusion, diphtheria toxin translocation is facilitated by depletion of membrane sphingolipids

  19. Resource Control: A Translocation Of The Scramble For Africa ...

    African Journals Online (AJOL)

    Adopting a theoretical framework successfully adapted from the biological and medical sciences, namely; translocation analysis, the paper traces the ancestry of the present resource control problem to the scramble, first, and then, the use of fiscal and revenue allocation commissions during the colonial era, and the ...

  20. Single-Molecule Studies of Bacterial Protein Translocation

    NARCIS (Netherlands)

    Kedrov, Alexej; Kusters, Ilja; Driessen, Arnold J. M.

    2013-01-01

    In prokaryotes, a large share of the proteins are secreted from the cell through a process that requires their translocation across the cytoplasmic membrane. This process is mediated by the universally conserved Sec system with homologues in the endoplasmic reticulum and thylakoid membranes of

  1. Introduction: translocal development, development corridors and development chains.

    NARCIS (Netherlands)

    Zoomers, E.B.; Westen, A.C.M. van

    2011-01-01

    This paper offers an introduction to this Special Issue of International Development Planning Review. It uses the concepts of translocal development, development corridors and development chains to secure a better grasp of what development means in the context of globalisation and how ‘local

  2. Concentration Polarization in Translocation of DNA through Nanopores and Nanochannels

    NARCIS (Netherlands)

    Das, S.; Dubsky, P.; van den Berg, Albert; Eijkel, Jan C.T.

    2012-01-01

    In this Letter we provide a theory to show that high-field electrokinetic translocation of DNA through nanopores or nanochannels causes large transient variations of the ionic concentrations in front and at the back of the DNA due to concentration polarization (CP). The CP causes strong local

  3. Transcuticular translocation of radionuclides on plant leaf surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Ken-ichi; Watanabe, Tadakazu; Ambe, Shizuko; Yamaguchi, Isamu [Institute of Physical and Chemical Research, Wako, Saitama (Japan)

    1996-12-31

    The cuticle covering all the outermost surfaces of the aerial parts of plants could play a selective role in uptake and translocation of radionuclides from air into plants. In this study, we investigated the transcuticular uptake and translocation behavior via water droplets of various radionuclides in red clover, orchard grass, Japanese radish and mung bean. Ten {mu}l of an aqueous solution of the multitracer generated from Au was applied to the upper surface of the 2nd leaf of the plants at the 5th leaf stage. The plants were then grown for 14 days at 25degC and 70% RH under illumination of artificial solar lights. The transcuticular uptake and translocation throughout the plant were periodically assayed by determining the radioactivity in the surface residue, the cuticle layer beneath the applied site, the leaf area outside the applied site, the other aerial parts and the root of the plant, using an HPGe detector. The applied radionuclides were absorbed into, in turn, the cuticle layer beneath the applied site and then translocated through the cuticle to the inner tissue and eventually to the other aerial parts and finally to the roots, of the plant. The distribution and accumulation in the plant seems to depend upon the characteristics of each radionuclide and plant species. Ca{sup *} and Te{sup *} tended to remain on leaf surfaces without being absorbed into the cuticle. On the other hand, Sc{sup *}, Co{sup *}, Zn{sup *}, Se{sup *}, Rb{sup *}, and Eu{sup *} were easily absorbed and translocated to every part of the plant including the root. The other radionuclides such as Be{sup *}, Mn{sup *}, Sr{sup *}, Y{sup *}, Ba{sup *}, Ce{sup *}, Pm{sup *}, Gd{sup *}, Hf{sup *}, Yb{sup *}, Lu{sup *}, Os{sup *}, Ir{sup *}, and Pt{sup *} remained in the region close to the site of their application. The above results possibly indicate the existence of mechanisms common to these plants for selective transcuticular uptake and translocation of radionuclides within plant

  4. Residues in the H+ Translocation Site Define the pKa for Sugar Binding to LacY†

    Science.gov (United States)

    Smirnova, Irina; Kasho, Vladimir; Sugihara, Junichi; Choe, Jun-Yong; Kaback, H. Ronald

    2009-01-01

    A remarkably high pKa of approximately 10.5 has been determined for sugar-binding affinity to the lactose permease of Escherichia coli (LacY), indicating that, under physiological conditions, substrate binds to fully protonated LacY. We have now systematically tested site-directed replacements for the residues involved in sugar binding, as well as H+ translocation and coupling, in order to determine which residues may be responsible for this alkaline pKa. Mutations in the sugar-binding site (Glu126, Trp151, Glu269) markedly decrease affinity for sugar but do not alter the pKa for binding. In contrast, replacements for residues involved in H+ translocation (Arg302, Tyr236, His322, Asp240, Glu325, Lys319) exhibit pKa values for sugar binding that are either shifted toward neutral pH or independent of pH. Values for the apparent dissociation constant for sugar binding (Kdapp) increase greatly for all mutants except neutral replacements for Glu325 or Lys319, which are characterized by remarkably high affinity sugar binding (i.e., low Kdapp) from pH 5.5 to pH 11. The pH dependence of the on- and off-rate constants for sugar binding measured directly by stopped-flow fluorometry implicates koff as a major factor for the affinity change at alkaline pH and confirms the effects of pH on Kdapp inferred from steady-state fluorometry. These results indicate that the high pKa for sugar binding by wild-type LacY cannot be ascribed to any single amino acid residue but appears to reside within a complex of residues involved in H+ translocation. There is structural evidence for water bound in this complex, and the water could be the site of protonation responsible for the pH dependence of sugar binding. PMID:19689129

  5. Computational determination of the effects of virulent Escherichia coli and salmonella bacteriophages on human gut.

    Science.gov (United States)

    Mostafa, Marwa Mostafa; Nassef, Mohammad; Badr, Amr

    2016-10-01

    Salmonella and Escherichia coli are different types of bacteria that cause food poisoning in humans. In the elderly, infants and people with chronic conditions, it is very dangerous if Salmonella or E. coli gets into the bloodstream and then they must be treated by phage therapy. Treating Salmonella and E. coli by phage therapy affects the gut flora. This research paper presents a system for detecting the effects of virulent E. coli and Salmonella bacteriophages on human gut. A method based on Domain-Domain Interactions (DDIs) model is implemented in the proposed system to determine the interactions between the proteins of human gut bacteria and the proteins of bacteriophages that infect virulent E. coli and Salmonella. The system helps gastroenterologists to realize the effect of injecting bacteriophages that infect virulent E. coli and Salmonella on the human gut. By testing the system over Enterobacteria phage 933W, Enterobacteria phage VT2-Sa and Enterobacteria phage P22, it resulted in four interactions between the proteins of the bacteriophages that infect E. coli O157:H7, E. coli O104:H4 and Salmonella typhimurium and the proteins of human gut bacterium strains. Several effects were detected such as: antibacterial activity against a number of bacterial species in human gut, regulation of cellular differentiation and organogenesis during gut, lung, and heart development, ammonia assimilation in bacteria, yeasts, and plants, energizing defense system and its function in the detoxification of lipopolysaccharide, and in the prevention of bacterial translocation in human gut. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Cold-inhibited phloem translocation in sugar beet

    International Nuclear Information System (INIS)

    Grusak, M.A.

    1985-01-01

    Experimental studies were undertaken on a simplified single source leaf-single sink leaf, or single source leaf-double sink leaf sugar beet system to investigate the responsive nature of the long-distance phloem translocation system to localized cooling perturbations on the source leaf petiole. Experiments were performed by using a steady state [ 14 C]-labelling system for the source leaf, and translocation into the sink leaf (leaves) was monitored with a Geiger-Mueller system. A specially designed Peltier apparatus enabled cooling of the source petiole to 1 0 C (or other desired temperatures) at various positions on the petiole, over different lengths, and at different rates of cooling. Initial experiment were designed to test the predictions of a mathematical recovery model of translocation inhibited by cold. The results did not support the mathematical model, but did suggest that vascular anastomoses may be involved in the recovery response. Selective petiolar incision/excision experiments showed that anastomoses were capable of re-establishing translocation following a disruption of flow. Studies with two monitored sink levels suggested that the inhibition to slow-coolings was not due to reduced translocation through the cooled source petiole region, but rather, was due to a repartitioning of flow among the terminal sinks (sink leaves and hypocotyl/crown region above the heat-girdled root). This repartitioning occurred via a redirection of flow through the vascular connections in the crown region of the plant, and appeared to be promoted by rapid, physical signals originating from the cooled region of the petiole

  7. MiT family translocation renal cell carcinoma.

    Science.gov (United States)

    Argani, Pedram

    2015-03-01

    The MiT subfamily of transcription factors includes TFE3, TFEB, TFC, and MiTF. Gene fusions involving two of these transcription factors have been identified in renal cell carcinoma (RCC). The Xp11 translocation RCCs were first officially recognized in the 2004 WHO renal tumor classification, and harbor gene fusions involving TFE3. The t(6;11) RCCs harbor a specific Alpha-TFEB gene fusion and were first officially recognized in the 2013 International Society of Urologic Pathology (ISUP) Vancouver classification of renal neoplasia. These two subtypes of translocation RCC have many similarities. Both were initially described in and disproportionately involve young patients, though adult translocation RCC may overall outnumber pediatric cases. Both often have unusual and distinctive morphologies; the Xp11 translocation RCCs frequently have clear cells with papillary architecture and abundant psammomatous bodies, while the t(6;11) RCCs frequently have a biphasic appearance with both large and small epithelioid cells and nodules of basement membrane material. However, the morphology of these two neoplasms can overlap, with one mimicking the other. Both of these RCCs underexpress epithelial immunohistochemical markers like cytokeratin and epithelial membrane antigen (EMA) relative to most other RCCs. Unlike other RCCs, both frequently express the cysteine protease cathepsin k and often express melanocytic markers like HMB45 and Melan A. Finally, TFE3 and TFEB have overlapping functional activity as these two transcription factors frequently heterodimerize and bind to the same targets. Therefore, on the basis of clinical, morphologic, immunohistochemical, and genetic similarities, the 2013 ISUP Vancouver classification of renal neoplasia grouped these two neoplasms together under the heading of "MiT family translocation RCC." This review summarizes our current knowledge of these recently described RCCs. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Atlas of alien and translocated indigenous aquatic animals in southern Africa

    CSIR Research Space (South Africa)

    De Moor, IJ

    1988-01-01

    Full Text Available This report serves as an introduction to the problem of alien and translocated aquatic animals in southern Africa is given followed by checklists of the different species which have been introduced into or translocated within the subcontinent...

  9. ANIMAL ENTEROTOXIGENIC ESCHERICHIA COLI

    Science.gov (United States)

    Dubreuil, J. Daniel; Isaacson, Richard E.; Schifferli, Dieter M.

    2016-01-01

    Enterotoxigenic Escherichia coli (ETEC) is the most common cause of E. coli diarrhea in farm animals. ETEC are characterized by the ability to produce two types of virulence factors; adhesins that promote binding to specific enterocyte receptors for intestinal colonization and enterotoxins responsible for fluid secretion. The best-characterized adhesins are expressed in the context of fimbriae, such as the F4 (also designated K88), F5 (K99), F6 (987P), F17 and F18 fimbriae. Once established in the animal small intestine, ETEC produces enterotoxin(s) that lead to diarrhea. The enterotoxins belong to two major classes; heat-labile toxin that consist of one active and five binding subunits (LT), and heat-stable toxins that are small polypeptides (STa, STb, and EAST1). This chapter describes the disease and pathogenesis of animal ETEC, the corresponding virulence genes and protein products of these bacteria, their regulation and targets in animal hosts, as well as mechanisms of action. Furthermore, vaccines, inhibitors, probiotics and the identification of potential new targets identified by genomics are presented in the context of animal ETEC. PMID:27735786

  10. Translocation Study of Some Zooxanthellae Clade to the Survival and Growth of Goniastrea Aspera After Bleaching

    OpenAIRE

    Purnomo, Pujiono W

    2014-01-01

    Inter-host translocation technique of zooxanthellae was attempted to prove Buddemier and Futin's (1993) theory on adaptation. The recent trend of coral products trading must be anticipated by its mass production through artificial techniques, the alternation of natural resources. Translocation bio-technique of zooxanthellae on coral was expected to resolve the problem and the translocation study should provide fundamental answer to coral recovery. The study of zooxanthellae translocation was ...

  11. Microbial Translocation in HIV Infection is Associated with Dyslipidemia, Insulin Resistance, and Risk of Myocardial Infarction

    DEFF Research Database (Denmark)

    Pedersen, Karin Kaereby; Pedersen, Maria; Trøseid, Marius

    2013-01-01

    Microbial translocation has been suggested to be a driver of immune activation and inflammation. We hypothesized that microbial translocation may be related to dyslipidemia, insulin resistance, and the risk of coronary heart disease in HIV-infected individuals.......Microbial translocation has been suggested to be a driver of immune activation and inflammation. We hypothesized that microbial translocation may be related to dyslipidemia, insulin resistance, and the risk of coronary heart disease in HIV-infected individuals....

  12. 40 CFR 798.5955 - Heritable translocation test in drosophila melanogaster.

    Science.gov (United States)

    2010-07-01

    ... drosophila melanogaster. 798.5955 Section 798.5955 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY....5955 Heritable translocation test in drosophila melanogaster. (a) Purpose. The heritable translocation test in Drosophila measures the induction of chromosomal translocations in germ cells of insects...

  13. Translocation as a conservation tool for Agassiz's desert tortoises: Survivorship, reproduction, and movements

    Science.gov (United States)

    K. E. Nussear; C. R. Tracy; P. A. Medica; D. S. Wilson; R. W. Marlow; P. S. Corn

    2012-01-01

    We translocated 120 Agassiz's desert tortoises to 5 sites in Nevada and Utah to evaluate the effects of translocation on tortoise survivorship, reproduction, and habitat use. Translocation sites included several elevations, and extended to sites with vegetation assemblages not typically associated with desert tortoises in order to explore the possibility of moving...

  14. Meiotic behaviour and spermatogenesis in male mice heterozygous for translocation types also occurring in man

    NARCIS (Netherlands)

    Nijhoff, J.H.

    1981-01-01

    In this thesis a start was made with meiotic observations of mouse translocation types - a Robertsonian translocation and a translocation between a metacentric and an acrocentric chromosome - which also occur in man. It is generally accepted that, when no chromosomal rearrangements are involved, man

  15. Dek-can rearrangement in translocation (6;9)(p23;q34)

    NARCIS (Netherlands)

    Soekarman, D.; von Lindern, M.; van der Plas, D. C.; Selleri, L.; Bartram, C. R.; Martiat, P.; Culligan, D.; Padua, R. A.; Hasper-Voogt, K. P.; Hagemeijer, A.

    1992-01-01

    The translocation (6;9)(p23;q34) is mainly found in specific subtypes of acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). The diagnosis of this translocation is not easy since the cytogenetic change is quite subtle. The two genes involved in this translocation were recently isolated

  16. Markers of immunity and bacterial translocation in cirrhosis

    DEFF Research Database (Denmark)

    Mortensen, Christian

    2015-01-01

    to be correlated to portal hypertension, a clinically relevant haemodynamic alteration, and appeared to be associated with increased mortality. To assess the consequences of BT on immunity, we developed an assay for the detection of bacterial DNA (bDNA), a novel marker of BT. Using the assay in the second study......Bacterial translocation (BT), the migration of enteric bacteria to extraintestinal sites, is related to immune stimulation and haemodynamic changes in experimental cirrhosis. These changes may be highly relevant to patients with cirrhosis, where changes in the circulation cause serious......, in 38 patients with ascites, we found no association between bDNA and immunity, in contrast to some previous findings. In the final paper, exploring one possible translocation route, we hypothesized a difference in bDNA levels between the blood from the veins draining the gut on one hand and the liver...

  17. Regulation of Neuronal Protein Trafficking and Translocation by SUMOylation

    Directory of Open Access Journals (Sweden)

    Jeremy M. Henley

    2012-05-01

    Full Text Available Post-translational modifications of proteins are essential for cell function. Covalent modification by SUMO (small ubiquitin-like modifier plays a role in multiple cell processes, including transcriptional regulation, DNA damage repair, protein localization and trafficking. Factors affecting protein localization and trafficking are particularly crucial in neurons because of their polarization, morphological complexity and functional specialization. SUMOylation has emerged as a major mediator of intranuclear and nucleo-cytoplasmic translocations of proteins involved in critical pathways such as circadian rhythm, apoptosis and protein degradation. In addition, SUMO-regulated re-localization of extranuclear proteins is required to sustain neuronal excitability and synaptic transmission. Thus, SUMOylation is a key arbiter of neuronal viability and function. Here, we provide an overview of recent advances in our understanding of regulation of neuronal protein localization and translocation by SUMO and highlight exciting areas of ongoing research.

  18. Sex Chromosome Translocations in the Evolution of Reproductive Isolation

    Science.gov (United States)

    Tracey, Martin L.

    1972-01-01

    Haldane's rule states that in organisms with differentiated sex chromosomes, hybrid sterility or inviability is generally expressed more frequently in the heterogametic sex. This observation has been variously explained as due to either genic or chromosomal imbalance. The fixation probabilities and mean times to fixation of sex-chromosome translocations of the type necessary to explain Haldane's rule on the basis of chromosomal imbalance have been estimated in small populations of Drosophila melanogaster. The fixation probability of an X chromosome carrying the long arm of the Y(X·YL) is approximately 30% greater than expected under the assumption of no selection. No fitness differences associated with the attached YL segment were detected. The fixation probability of a deficient Y chromosome is 300% greater than expected when the X chromosome contains the deleted portion of the Y. It is suggested that sex-chromosome translocations may play a role in the establishment of reproductive isolation. PMID:4630586

  19. Analysis of photosynthate translocation velocity and measurement of weighted average velocity in transporting pathway of crops

    International Nuclear Information System (INIS)

    Ge Cailin; Luo Shishi; Gong Jian; Zhang Hao; Ma Fei

    1996-08-01

    The translocation profile pattern of 14 C-photosynthate along the transporting pathway in crops were monitored by pulse-labelling a mature leaf with 14 CO 2 . The progressive spreading of translocation profile pattern along the sheath or stem indicates that the translocation of photosynthate along the sheath or stem proceed with a range of velocities rather than with just a single velocity. The method for measuring the weighted average velocity of photosynthate translocation along the sheath or stem was established in living crops. The weighted average velocity and the maximum velocity of photosynthate translocation along the sheath in rice and maize were measured actually. (4 figs., 3 tabs.)

  20. A strategy for generation and balancing of autosome: Y chromosome translocations.

    Science.gov (United States)

    Joshi, Sonal S; Cheong, Han; Meller, Victoria H

    2014-01-01

    We describe a method for generation and maintenance of translocations that move large autosomal segments onto the Y chromosome. Using this strategy we produced ( 2;Y) translocations that relocate between 1.5 and 4.8 Mb of the 2nd chromosome.. All translocations were easily balanced over a male-specific lethal 1 (msl-1) mutant chromosome. Both halves of the translocation carry visible markers, as well as P-element ends that enable molecular confirmation. Halves of these translocations can be separated to produce offspring with duplications and with lethal second chromosome deficiencies . Such large deficiencies are otherwise tedious to generate and maintain.

  1. Polymer translocation in the presence of excluded volume and explicit hydrodynamic interactions

    International Nuclear Information System (INIS)

    Guillouzic, Steve; Slater, Gary W.

    2006-01-01

    Molecular Dynamics simulations of polymer translocation are hereby reported. No external force was applied to the polymer during translocation, and the dynamics was dominated by polymer-pore interactions. It was found that hydrodynamic interactions play an important role in the relaxation of the polymer on each side of the membrane but have a negligible impact on the translocation process itself. Also, the scaling laws obtained for the relaxation and translocation times indicate that long translocating polymers may be considered to be following a quasi-equilibrium anomalous diffusion process in the absence of external forces

  2. International study of factors affecting human chromosome translocations

    Czech Academy of Sciences Publication Activity Database

    Sigurdson, A.J.; Ha, M.; Hauptmann, M.; Bhatti, P.; Šrám, Radim; Beskid, Olena; Tawn, E.J.; Whitehouse, C.A.; Lindholm, C.; Nakano, M.; Kodama, Y.; Nakamura, N.; Vorobtsova, I.; Oestreicher, U.; Stephan, G.; Yong, L.C.; Bauchinger, M.; Schmid, E.; Chung, H.W.; Darroudi, F.; Roy, L.; Voisin, P.; Barquinero, J.F.; Livingston, G.; Blakey, D.; Hayata, I.; Zhang, W.; Wang, Ch.; Benett, L.M.; Littlefield, L.G.; Edwards, A.A.; Kleinerman, R.A.; Tucker, J.D.

    2008-01-01

    Roč. 652, č. 2 (2008), s. 112-121 ISSN 1383-5718 R&D Projects: GA MŽP SL/5/160/05; GA MŽP SI/340/2/00; GA MŽP SL/740/5/03 Institutional research plan: CEZ:AV0Z50390512 Keywords : Chromosome translocations * FISH * Background frequency Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.363, year: 2008

  3. "Translocal Express" juba täna! / Rael Artel

    Index Scriptorium Estoniae

    Artel, Rael, 1980-

    2009-01-01

    27. märtsil algab Kumu Kunstimuuseumis "Public Preparation'i" ("Avalik ettevalmistus") sarja rahvusvaheline seminar "Translocal Express. Golden Age" ("Translokaalne ekspress. Kuldaeg"), kus on kõne all ajalookirjutamise ja kollektiivse mälu roll praegu domineerivas natsionalistlikus diskursuses ja selle käsitlemine kaasaegses kunstis. Seminaril on lähtutud eelkõige kunstnike Martin Krenni (Viin) ja Kristina Normani teoste tutvustamisest

  4. Single-strand DNA molecule translocation through nanoelectrode gaps

    International Nuclear Information System (INIS)

    Zhao Xiongce; Payne, Christina M; Cummings, Peter T; Lee, James W

    2007-01-01

    Molecular dynamics simulations were performed to investigate the translocation of single-strand DNA through nanoscale electrode gaps under the action of a constant driving force. The application behind this theoretical study is a proposal to use nanoelectrodes as a screening gap as part of a rapid genomic sequencing device. Preliminary results from a series of simulations using various gap widths and driving forces suggest that the narrowest electrode gap that a single-strand DNA can pass is ∼1.5 nm. The minimum force required to initiate the translocation within nanoseconds is ∼0.3 nN. Simulations using DNA segments of various lengths indicate that the minimum initiation force is insensitive to the length of DNA. However, the average threading velocity of DNA varies appreciably from short to long DNA segments. We attribute such variation to the different nature of drag force experienced by the short and long DNA segments in the environment. It is found that DNA molecules deform significantly to fit in the shape of the nanogap during the translocation

  5. Spatial behaviour and survival of translocated wild brown hares

    Directory of Open Access Journals (Sweden)

    Fischer, C.

    2012-01-01

    Full Text Available The fragility of many populations of brown hares in Western Europe is a concern for managers, hunters and naturalists. We took advantage of a locally high density population to use wild individuals to restock areas where the species had disappeared or was close to disappearing. The aim of the project was to assess the evolution of the spatial behaviour after release using radio–tracking. Over 150 wild brown hares were translocated, one third of which were fitted with radio collars. In addition, fifteen individuals were radio–tagged and released back into the source population as a control. Most individuals settled in less than two months and their seasonal home range, once settled, was similar to that observed in the source population. Mean duration of tracking was not significantly different between the two groups. Moreover, two years after the last translocation, tagged individuals can still be observed, but most hares present are not tagged, which indicates natural reproduction of the released individuals. The translocation of wild individuals thus appears to give encouraging results.

  6. Dominant-lethal mutations and heritable translocations in mice

    International Nuclear Information System (INIS)

    Generoso, W.M.

    1983-01-01

    Chromosome aberrations are a major component of radiation or chemically induced genetic damage in mammalian germ cells. The types of aberration produced are dependent upon the mutagen used and the germ-cell stage treated. For example, in male meiotic and postmeiotic germ cells certain alkylating chemicals induce both dominant-lethal mutations and heritable translocations while others induce primarily dominant-lethal mutations. Production of these two endpoints appears to be determined by the stability of alkylation products with the chromosomes. If the reaction products are intact in the male chromosomes at the time of sperm entry, they may be repaired in fertilized eggs. If repair is not effected and the alkylation products persist to the time of pronuclear chromosome replication, they lead to chromatid-type aberrations and eventually to dominant-lethality. The production of heritable translocations, on the other hand, requires a transformation of unstable alkylation products into suitable intermediate lesions. The process by which these lesions are converted into chromosome exchange within the male genome takes place after sperm enters the egg but prior to the time of pronuclear chromosome replication (i.e., chromosome-type). Thus, dominant-lethal mutations result from both chromatid- and chromosome-type aberrations while heritable translocations result primarily from the latter type. DNA target sites associated with the production of these two endpoints are discussed

  7. Dominant-lethal mutations and heritable translocations in mice

    Energy Technology Data Exchange (ETDEWEB)

    Generoso, W.M.

    1983-01-01

    Chromosome aberrations are a major component of radiation or chemically induced genetic damage in mammalian germ cells. The types of aberration produced are dependent upon the mutagen used and the germ-cell stage treated. For example, in male meiotic and postmeiotic germ cells certain alkylating chemicals induce both dominant-lethal mutations and heritable translocations while others induce primarily dominant-lethal mutations. Production of these two endpoints appears to be determined by the stability of alkylation products with the chromosomes. If the reaction products are intact in the male chromosomes at the time of sperm entry, they may be repaired in fertilized eggs. If repair is not effected and the alkylation products persist to the time of pronuclear chromosome replication, they lead to chromatid-type aberrations and eventually to dominant-lethality. The production of heritable translocations, on the other hand, requires a transformation of unstable alkylation products into suitable intermediate lesions. The process by which these lesions are converted into chromosome exchange within the male genome takes place after sperm enters the egg but prior to the time of pronuclear chromosome replication (i.e., chromosome-type). Thus, dominant-lethal mutations result from both chromatid- and chromosome-type aberrations while heritable translocations result primarily from the latter type. DNA target sites associated with the production of these two endpoints are discussed.

  8. Black bears in Arkansas: Characteristics of a successful translocation

    Science.gov (United States)

    Smith, Kimberly G.; Clark, Joseph D.

    1994-01-01

    In 1958, the Arkansas Game and Fish Commission began translocating black bears (Ursus americanus) from Minnesota to the Interior Highlands (Ozark and Ouachita mountains) of Arkansas where bears had been extirpated early in this century. This project continued for 11 years with little public imput, during which time an estimated 254 bears were released. We estimate there are now >2,500 bears in the Interior Highlands of Arkansas, Missouri, and Oklahoma, making it one of the most successful translocations of a Carnivora. Factors that contributed to the success include use of wild-captured animals, elimination of major factors associated with extirpation, release into prime habitats within the former range, multiple release sites, release of 20–40 animals/year for eight years, and release of mostly males prior to release of mostly females. Studies on two allopatric populations demonstrate that they are now diverging in some demographic characteristics, including litter size, cub survivorship, and adult sex-ratio. Translocation of black bears to the Interior Highlands is successful in terms of numbers of animals, but it will not be truly successful until people accept black bears as part of the regional fauna. To that end, those associated with management and research of bears in Arkansas are now focussing on public education and control of nuisance bears.

  9. Translocation of 11C from leaves of Helianthus: preliminary results

    International Nuclear Information System (INIS)

    Fensom, D.S.; Aikman, D.; Scobie, J.; Drinkwater, A.; Ledingham, K.W.O.

    1977-01-01

    11 C fed to leaves as 11 CO 2 was used to study the dynamics of short-term translocation of photosynthate in Helianthus. As in 14 C studies small amounts of tracer were often detected in the stem close to the fed leaf in th first 5 min, followed by a larger mass flow after 15 min. The speed of mass flow of tracer movement was calculated to be 60 to 400 cm.h -1 depending on the method of calculation. There was no evidence in the premass flow for discrete spots along the stem or petiole where tracer accumulated. Neither was there firm evidence for pulses of tracer moving steadily forward, but there were point fluctuations of greater variability than would be expected by chance alone, which suggest the possibility of aberrations of movement superimposed on the mass flow. Details of these aberrations could not be assessed with certainty from these preliminary experiments owing to the rather low tracer activity. The translocation profiles were sensitive to the prior light conditioning of the plant and above all to chilling. In Helianthus the latter produced temporary restrictions in translocation which lasted for some 10-12 min. (author)

  10. Asymptomatic bacteriuria Escherichia coli strains

    DEFF Research Database (Denmark)

    Hancock, Viktoria; Nielsen, E.M.; Klemm, Per

    2006-01-01

    Urinary tract infections (UTIs) affect millions of people each year. Escherichia coli is the most common organism associated with asymptomatic bacteriuria (ABU) in humans. Persons affected by ABU may carry a particular E. coli strain for extended periods of time without any symptoms. In contrast...... to uropathogenic E. coli (UPEC) that cause symptomatic UTI, very little is known about the mechanisms by which these strains colonize the urinary tract. Here, we have investigated the growth characteristics in human urine as well as adhesin repertoire of nine ABU strains; the ability of ABU strains to compete...

  11. Ammonium recruitment and ammonia transport by E. coli ammonia channel AmtB

    DEFF Research Database (Denmark)

    Nygaard, Thomas Pedersen; Rovira, C.; Peters, Günther H.j.

    2006-01-01

    To investigate substrate recruitment and transport across the Escherichia coli Ammonia transporter B (AmtB) protein, we performed molecular dynamics simulations of the AmtB trimer. We have identified residues important in recruitment of ammonium and intraluminal binding sites selective of ammonium......, which provide a means of cation selectivity. Our results indicate that A162 guides translocation of an extraluminal ammonium into the pore lumen. We propose a mechanism for transporting the intraluminally recruited proton back to periplasm. Our mechanism conforms to net transport of ammonia and can...

  12. Chromosomal features of Escherichia coli serotype O2:K2, an avian pathogenic E. coli

    DEFF Research Database (Denmark)

    Jørgensen, Steffen L; Kudirkiene, Egle; Li, Lili

    2017-01-01

    Escherichia coli causing infection outside the gastrointestinal system are referred to as extra-intestinal pathogenic E. coli. Avian pathogenic E. coli is a subgroup of extra-intestinal pathogenic E. coli and infections due to avian pathogenic E. coli have major impact on poultry production econo...

  13. TFE3-positive renal cell carcinomas are not always Xp11 translocation carcinomas: Report of a case with a TPM3-ALK translocation.

    Science.gov (United States)

    Thorner, Paul Scott; Shago, Mary; Marrano, Paula; Shaikh, Furqan; Somers, Gino R

    2016-10-01

    Translocation-associated renal cell carcinoma (RCC) is a distinct subtype of RCC with gene rearrangements of the TFE3 or TFEB loci. The TFE3 gene is located at Xp11 and can fuse to a number of translocation partners, resulting in high nuclear expression of TFE3 protein. TFE3 immunostaining is often used as a surrogate marker for a TFE3 translocation. We report a case of an RCC that expressed TFE3 but showed only gain of TFE3 rather than a translocation. Moreover, this case had a t(1;2) translocation fusing ALK and TMP3, identical to that seen in inflammatory myofibroblastic tumour. There was resulting overexpression of ALK protein in a cytoplasmic and membranous pattern. The patient was not treated with chemotherapy but following regional nodal recurrence, an ALK inhibitor was added and the patient remains alive one year later. There are only rare reports of RCC with an ALK-TMP3 fusion, and these tumours can express TFE3 on some unknown basis not related to a TFE3 translocation. Any RCC positive for TFE3 and lacking a translocation should be tested for ALK expression and translocation. Recognition of this subtype of RCC will allow ALK inhibitor therapy to be added, in the hope of improving patient outcome. Copyright © 2016 Elsevier GmbH. All rights reserved.

  14. Efficient induction of Wheat-agropyron cristatum 6P translocation lines and GISH detection.

    Directory of Open Access Journals (Sweden)

    Liqiang Song

    Full Text Available The narrow genetic background restricts wheat yield and quality improvement. The wild relatives of wheat are the huge gene pools for wheat improvement and can broaden its genetic basis. Production of wheat-alien translocation lines can transfer alien genes to wheat. So it is important to develop an efficient method to induce wheat-alien chromosome translocation. Agropyroncristatum (P genome carries many potential genes beneficial to disease resistance, stress tolerance and high yield. Chromosome 6P possesses the desirable genes exhibiting good agronomic traits, such as high grain number per spike, powdery mildew resistance and stress tolerance. In this study, the wheat-A. cristatum disomic addition was used as bridge material to produce wheat-A. cristatum translocation lines induced by (60Co-γirradiation. The results of genomic in situ hybridization showed that 216 plants contained alien chromosome translocation among 571 self-pollinated progenies. The frequency of translocation was 37.83%, much higher than previous reports. Moreover, various alien translocation types were identified. The analysis of M2 showed that 62.5% of intergeneric translocation lines grew normally without losing the translocated chromosomes. The paper reported a high efficient technical method for inducing alien translocation between wheat and Agropyroncristatum. Additionally, these translocation lines will be valuable for not only basic research on genetic balance, interaction and expression of different chromosome segments of wheat and alien species, but also wheat breeding programs to utilize superior agronomic traits and good compensation effect from alien chromosomes.

  15. Pertussis Toxin Exploits Host Cell Signaling Pathways Induced by Meningitis-Causing E. coli K1-RS218 and Enhances Adherence of Monocytic THP-1 Cells to Human Cerebral Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Laura Julia Starost

    2016-10-01

    Full Text Available Pertussis toxin (PTx, the major virulence factor of the whooping cough-causing bacterial pathogen Bordetella pertussis, permeabilizes the blood–brain barrier (BBB in vitro and in vivo. Breaking barriers might promote translocation of meningitis-causing bacteria across the BBB, thereby facilitating infection. PTx activates several host cell signaling pathways exploited by the neonatal meningitis-causing Escherichia coli K1-RS218 for invasion and translocation across the BBB. Here, we investigated whether PTx and E. coli K1-RS218 exert similar effects on MAPK p38, NF-κB activation and transcription of downstream targets in human cerebral endothelial TY10 cells using qRT-PCR, Western blotting, and ELISA in combination with specific inhibitors. PTx and E. coli K1-RS218 activate MAPK p38, but only E. coli K1-RS218 activates the NF-κB pathway. mRNA and protein levels of p38 and NF-κB downstream targets including IL-6, IL-8, CxCL-1, CxCL-2 and ICAM-1 were increased. The p38 specific inhibitor SB203590 blocked PTx-enhanced activity, whereas E. coli K1-RS218’s effects were inhibited by the NF-κB inhibitor Bay 11-7082. Further, we found that PTx enhances the adherence of human monocytic THP-1 cells to human cerebral endothelial TY10 cells, thereby contributing to enhanced translocation. These modulations of host cell signaling pathways by PTx and meningitis-causing E. coli support their contributions to pathogen and monocytic THP-1 cells translocation across the BBB.

  16. Diarrheagenic Escherichia coli Markers and Phenotypes among Fecal E. coli Isolates Collected from Nicaraguan Infants ▿

    OpenAIRE

    Reyes, Daniel; Vilchez, Samuel; Paniagua, Margarita; Colque-Navarro, Patricia; Weintraub, Andrej; Möllby, Roland; Kühn, Inger

    2010-01-01

    We analyzed the prevalence of diarrheagenic Escherichia coli (DEC) markers and common phenotypes in 2,164 E. coli isolates from 282 DEC-positive samples. Enteropathogenic E. coli (EPEC) and enteroaggregative E. coli (EAEC) were very diverse and were not correlated with diarrhea. Enterotoxigenic E. coli (ETEC) estA and enterohemorrhagic E. coli (EHEC) belonged to a few phenotypes and were significantly correlated with diarrhea.

  17. Protein folding and translocation : single-molecule investigations

    NARCIS (Netherlands)

    Leeuwen, Rudolphus Gerardus Henricus van

    2006-01-01

    This thesis describes experiments, in which we used an optical-tweezers setup to study a number of biological systems. We studied the interaction between the E. coli molecular chaperone SecB and a protein that was being unfolded and refolded using our optical tweezers setup. Our measurements clearly

  18. Absorption and translocation of arsenate arsenic by coffee plants

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, J F; Yamaguchi, S

    1964-01-01

    Studies on arsenate arsenic absorption and translocation in coffee plants were carried out using arsenic-77 applied either to leaves or to roots through the nutrient solution. The youngest leaves were unable to export arsenic and only an acropetal movement in the transpiration stream was observed. From the second pair of leaves, it moved into the growing leaves. From the fourth pair it moved downward through the stem and into the roots. Roots absorbed high amounts of arsenate once absorbed it moved via the xylem of the transpiration stream into the leaves. 7 references, 2 figures.

  19. Structure-Function Analysis of the DNA Translocating Portal of the Bacteriophage T4 Packaging Machine

    Science.gov (United States)

    Padilla-Sanchez, Victor; Gao, Song; Kim, Hyung Rae; Kihara, Daisuke; Sun, Lei; Rossmann, Michael G.; Rao, Venigalla B.

    2013-01-01

    Tailed bacteriophages and herpesviruses consist of a structurally well conserved dodecameric portal at a special five-fold vertex of the capsid. The portal plays critical roles in head assembly, genome packaging, neck/tail attachment, and genome ejection. Although the structures of portals from phages φ29, SPP1 and P22 have been determined, their mechanistic roles have not been well understood. Structural analysis of phage T4 portal (gp20) has been hampered because of its unusual interaction with the E. coli inner membrane. Here, we predict atomic models for the T4 portal monomer and dodecamer, and fit the dodecamer into the cryoEM density of the phage portal vertex. The core structure, like that from other phages, is cone-shaped with the wider end containing the “wing” and “crown” domains inside the phage head. A long “stem” encloses a central channel, and a narrow “stalk” protrudes outside the capsid. A biochemical approach was developed to analyze portal function by incorporating plasmid-expressed portal protein into phage heads and determining the effect of mutations on head assembly, DNA translocation, and virion production. We found that the protruding loops of the stalk domain are involved in assembling the DNA packaging motor. A loop that connects the stalk to the channel might be required for communication between the motor and portal. The “tunnel” loops that project into the channel are essential for sealing the packaged head. These studies established that the portal is required throughout the DNA packaging process, with different domains participating at different stages of genome packaging. PMID:24126213

  20. Structure-function analysis of the DNA translocating portal of the bacteriophage T4 packaging machine.

    Science.gov (United States)

    Padilla-Sanchez, Victor; Gao, Song; Kim, Hyung Rae; Kihara, Daisuke; Sun, Lei; Rossmann, Michael G; Rao, Venigalla B

    2014-03-06

    Tailed bacteriophages and herpesviruses consist of a structurally well conserved dodecameric portal at a special 5-fold vertex of the capsid. The portal plays critical roles in head assembly, genome packaging, neck/tail attachment, and genome ejection. Although the structures of portals from phages φ29, SPP1, and P22 have been determined, their mechanistic roles have not been well understood. Structural analysis of phage T4 portal (gp20) has been hampered because of its unusual interaction with the Escherichia coli inner membrane. Here, we predict atomic models for the T4 portal monomer and dodecamer, and we fit the dodecamer into the cryo-electron microscopy density of the phage portal vertex. The core structure, like that from other phages, is cone shaped with the wider end containing the "wing" and "crown" domains inside the phage head. A long "stem" encloses a central channel, and a narrow "stalk" protrudes outside the capsid. A biochemical approach was developed to analyze portal function by incorporating plasmid-expressed portal protein into phage heads and determining the effect of mutations on head assembly, DNA translocation, and virion production. We found that the protruding loops of the stalk domain are involved in assembling the DNA packaging motor. A loop that connects the stalk to the channel might be required for communication between the motor and the portal. The "tunnel" loops that project into the channel are essential for sealing the packaged head. These studies established that the portal is required throughout the DNA packaging process, with different domains participating at different stages of genome packaging. © 2013.

  1. Sorption, Uptake, and Translocation of Pharmaceuticals across Multiple Interfaces in Soil Environment

    Science.gov (United States)

    Zhang, W.; Liu, C. H.; Bhalsod, G.; Zhang, Y.; Chuang, Y. H.; Boyd, S. A.; Teppen, B. J.; Tiedje, J. M.; Li, H.

    2015-12-01

    Pharmaceuticals are contaminants of emerging concern frequently detected in soil and water environments, raising serious questions on their potential impact on human and ecosystem health. Overuse and environmental release of antibiotics (i.e., a group of pharmaceuticals extensively used in human medicine and animal agriculture) pose enormous threats to the health of human, animal, and the environment, due to proliferation of antibiotic resistant bacteria. Recently, we have examined interactions of pharmaceuticals with soil geosorbents, bacteria, and vegetable crops in order to elucidate pathways of sorption, uptake, and translocation of pharmaceuticals across the multiple interfaces in soils. Sorption of pharmaceuticals by biochars was studied to assess the potential of biochar soil amendment for reducing the transport and bioavailability of antibiotics. Our preliminary results show that carbonaceous materials such as biochars and activated carbon had strong sorption capacities for antibiotics, and consequently decreased the uptake and antibiotic resistance gene expression by an Escherichia coli bioreporter. Thus, biochar soil amendment showed the potential for reducing selection pressure on antibiotic resistant bacteria. Additionally, since consumption of pharmaceutical-tainted food is a direct exposure pathway for humans, it is important to assess the uptake and accumulation of pharmaceuticals in food crops grown in contaminated soils or irrigated with reclaimed water. Therefore, we have investigated the uptake and accumulations of pharmaceuticals in greenhouse-grown lettuce under contrasting irrigation practices (i.e., overhead or surface irrigations). Preliminary results indicate that greater pharmaceutical concentrations were measured in overhead irrigated lettuce than in surface irrigated lettuce. This could have important implications when selecting irrigation scheme to use the reclaimed water for crop irrigation. In summary, proper soil and water management

  2. Use of chromosome translocations for measuring prior environment exposures in humans

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, J. D.

    1997-05-01

    Recent advances in cytogenetic methodology are beginning to have a major impact upon our ability to provide assessments of environmental exposure in humans. The advent of fluorescent-based techniques for `painting` whole chromosomes has made the analysis of chromosome translocations rapid, specific, sensitive and routine. Chromosome painting has been used to address a wide variety of scientific questions, resulting in an increased understanding of the biological consequences of adverse environmental exposure. This paper describes the use of chromosome translocations as a biological marker of exposure and effect in humans. The relevance of translocations is discussed, as are the advantages and disadvantages of painting compared to classical cytogenetic methods for translocation evaluation. The factors to consider in the use of translocations as a retrospective indicator of exposure are then described. Several theoretical parameters that are important to the use of translocations are provided, and the paper concludes with a vision for the future of cytogenetic methodology.

  3. Akt phosphorylation is essential for nuclear translocation and retention in NGF-stimulated PC12 cells

    International Nuclear Information System (INIS)

    Truong Le Xuan Nguyen; Choi, Joung Woo; Lee, Sang Bae; Ye, Keqiang; Woo, Soo-Dong; Lee, Kyung-Hoon; Ahn, Jee-Yin

    2006-01-01

    Nerve growth factor (NGF) elicits Akt translocation into the nucleus, where it phosphorylates nuclear targets. Here, we describe that Akt phosphorylation can promote the nuclear translocation of Akt and is necessary for its nuclear retention. Overexpression of Akt-K179A, T308A, S473A-mutant failed to show either nuclear translocation or nuclear Akt phosphorylation, whereas expression of wild-type counterpart elicited profound Akt phosphorylation and induced nuclear translocation under NGF stimulation. Employing the PI3K inhibitor and a variety of mutants PI3K, we showed that nuclear translocation of Akt was mediated by activation of PI3K, and Akt phosphorylation status in the nucleus required PI3K activity. Thus the activity of PI3K might contribute to the nuclear translocation of Akt, and that Akt phosphorylation is essential for its nuclear retention under NGF stimulation conditions

  4. Polymer translocation under a pulling force: Scaling arguments and threshold forces

    Science.gov (United States)

    Menais, Timothée

    2018-02-01

    DNA translocation through nanopores is one of the most promising strategies for next-generation sequencing technologies. Most experimental and numerical works have focused on polymer translocation biased by electrophoresis, where a pulling force acts on the polymer within the nanopore. An alternative strategy, however, is emerging, which uses optical or magnetic tweezers. In this case, the pulling force is exerted directly at one end of the polymer, which strongly modifies the translocation process. In this paper, we report numerical simulations of both linear and structured (mimicking DNA) polymer models, simple enough to allow for a statistical treatment of the pore structure effects on the translocation time probability distributions. Based on extremely extended computer simulation data, we (i) propose scaling arguments for an extension of the predicted translocation times τ ˜N2F-1 over the moderate forces range and (ii) analyze the effect of pore size and polymer structuration on translocation times τ .

  5. Insulin-induced translocation of IR to the nucleus in insulin responsive cells requires a nuclear translocation sequence.

    Science.gov (United States)

    Kesten, Dov; Horovitz-Fried, Miriam; Brutman-Barazani, Tamar; Sampson, Sanford R

    2018-04-01

    Insulin binding to its cell surface receptor (IR) activates a cascade of events leading to its biological effects. The Insulin-IR complex is rapidly internalized and then is either recycled back to the plasma membrane or sent to lysosomes for degradation. Although most of the receptor is recycled or degraded, a small amount may escape this pathway and migrate to the nucleus of the cell where it might be important in promulgation of receptor signals. In this study we explored the mechanism by which insulin induces IR translocation to the cell nucleus. Experiments were performed cultured L6 myoblasts, AML liver cells and 3T3-L1 adipocytes. Insulin treatment induced a rapid increase in nuclear IR protein levels within 2 to 5 min. Treatment with WGA, an inhibitor of nuclear import, reduced insulin-induced increases nuclear IR protein; IR was, however, translocated to a perinuclear location. Bioinformatics tools predicted a potential nuclear localization sequence (NLS) on IR. Immunofluorescence staining showed that a point mutation on the predicted NLS blocked insulin-induced IR nuclear translocation. In addition, blockade of nuclear IR activation in isolated nuclei by an IR blocking antibody abrogated insulin-induced increases in IR tyrosine phosphorylation and nuclear PKCδ levels. Furthermore, over expression of mutated IR reduced insulin-induced glucose uptake and PKB phosphorylation. When added to isolated nuclei, insulin induced IR phosphorylation but had no effect on nuclear IR protein levels. These results raise questions regarding the possible role of nuclear IR in IR signaling and insulin resistance. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Balanced translocation linked to psychiatric disorder, glutamate, and cortical structure/function

    OpenAIRE

    Thomson, Pippa A; Duff, Barbara; Blackwood, Douglas H R; Romaniuk, Liana; Watson, Andrew; Whalley, Heather C; Li, Xiang; Dauvermann, Maria R; Moorhead, T William J; Bois, Catherine; Ryan, Niamh M; Redpath, Holly; Hall, Lynsey; Morris, Stewart W; van Beek, Edwin J R

    2016-01-01

    Rare genetic variants of large effect can help elucidate the pathophysiology of brain disorders. Here we expand the clinical and genetic analyses of a family with a (1;11)(q42;q14.3) translocation multiply affected by major psychiatric illness and test the effect of the translocation on the structure and function of prefrontal, and temporal brain regions. The translocation showed significant linkage (LOD score 6.1) with a clinical phenotype that included schizophrenia, schizoaffective disorde...

  7. Survival of translocated sharp-tailed grouse: Temporal threshold and age effects

    Science.gov (United States)

    Mathews, Steven; Coates, Peter S.; Delehanty, David J.

    2016-01-01

    Context: The Columbian sharp-tailed grouse (Tympanuchus phasianellus columbianus) is a subspecies of conservation concern in the western United States, currently occupying ≤10% of its historic range. Land and management agencies are employing translocation techniques to restore Columbian sharp-tailed grouse (CSTG) populations. However, establishing self-sustaining populations by translocating grouse often is unsuccessful, owing, in part, to low survivorship of translocated grouse following release.Aims: We measured and modelled patterns of CSTG mortality for 150 days following translocation into historic range, to better understand patterns and causes of success or failure in conservation efforts to re-establish grouse populations.Methods: We conducted two independent multi-year translocations and evaluated individual and temporal factors associated with CSTG survival up to 150 days following their release. Both translocations were reintroduction attempts in Nevada, USA, to establish viable populations of CSTG into their historic range.Key results: We observed a clear temporal threshold in survival probability, with CSTG mortality substantially higher during the first 50 days following release than during the subsequent 100 days. Additionally, translocated yearling grouse exhibited higher overall survival (0.669 ± 0.062) than did adults (0.420 ± 0.052) across the 150-day period and higher survival than adults both before and after the 50-day temporal threshold.Conclusions: Translocated CSTG are especially vulnerable to mortality for 50 days following release, whereas translocated yearling grouse are more resistant to mortality than are adult grouse. On the basis of the likelihood of survival, yearling CSTG are better candidates for population restoration through translocation than are adult grouse.Implications: Management actions that ameliorate mortality factors for 50 days following translocation and translocations that employ yearling grouse will

  8. Meiotic behaviour and spermatogenesis in male mice heterozygous for translocation types also occurring in man

    International Nuclear Information System (INIS)

    Nijhoff, J.H.

    1981-01-01

    In this thesis a start was made with meiotic observations of mouse translocation types - a Robertsonian translocation and a translocation between a metacentric and an acrocentric chromosome - which also occur in man. As an exogeneous factor of possible influence, the meiotic effects of two types of radiation (fission neutrons and X-rays) administered at relatively low doses 2 and 3 hours before prometaphase-metaphase II (probably during metaphase-anaphase I), were determined in Rb4Bnr/+-males. (Auth.)

  9. Occurence of translocations between irradiated and intact chromosomes of Drosophila melanogaster

    International Nuclear Information System (INIS)

    Myasnyankina, E.N.; Abeleva, Eh.A.; Generalova, M.V.

    1980-01-01

    Two translocations between irradiated father and intact mother autosomes are obtained in Drosophila melanogaster. Five out of 283 regular translocations (between the second and the third chromosomes of an irradiated male) are accompanied by a recombination over the second or the third chromosomes. Nine flies out of twenty considered to be recombinants, could originate due to mutations. The data obtained prove that intact female autosomes can take part in the exchange with homologic (recombinations) and heterologic (translocations) irradiated male autosomes

  10. Translocation of photoassimilates in γ-irradiated soybean plants

    International Nuclear Information System (INIS)

    Ursino, D.J.; Schefski, H.; Latour, P.W.

    1977-01-01

    Young soybean plants received on a single occasion a dose of 3.75 krads of γ-radiation after which they were allowed to photoassimilate 14 CO 2 so that the magnitude of translocation and distribution pattern of exported 14 C could be determined. In comparison to the non-irradiated controls, plants exposed to ionizing radiation showed a large reduction, almost 70%, in the magnitude of 14 C exported from the source leaf in a one hour period. Furthermore, the pattern of distribution of exported 14 C was altered such that less was exported to the shoot apex region and more to the region below the node of the source leaf. Replacement of the shoot apex with 20 ppm IAA immediately following irradiation completely restored the pattern of distribution but was able to only partially increase the magnitude of translocation. These results are interpreted with reference to the results from the author's previous study with soybean showing radiation effects on photosynthesis and shoot development. (author)

  11. Myeloid translocation genes differentially regulate colorectal cancer programs

    Science.gov (United States)

    Parang, Bobak; Bradley, Amber M.; Mittal, Mukul K.; Short, Sarah P.; Thompson, Joshua J.; Barrett, Caitlyn W.; Naik, Rishi D.; Bilotta, Anthony J.; Washington, Mary K.; Revetta, Frank L.; Smith, Jesse J.; Chen, Xi; Wilson, Keith T.; Hiebert, Scott W.; Williams, Christopher S.

    2016-01-01

    Myeloid translocation genes (MTGs), originally identified as chromosomal translocations in acute myelogenous leukemia, are transcriptional corepressors that regulate hematopoietic stem cell programs. Analysis of The Cancer Genome Atlas (TCGA) database revealed that MTGs were mutated in epithelial malignancy and suggested that loss of function might promote tumorigenesis. Genetic deletion of MTGR1 and MTG16 in the mouse has revealed unexpected and unique roles within the intestinal epithelium. Mtgr1−/− mice have progressive depletion of all intestinal secretory cells, and Mtg16−/− mice have a decrease in goblet cells. Furthermore, both Mtgr1−/− and Mtg16−/− mice have increased intestinal epithelial cell proliferation. We thus hypothesized that loss of MTGR1 or MTG16 would modify Apc1638/+-dependent intestinal tumorigenesis. Mtgr1−/− mice, but not Mtg16−/− mice, had a 10-fold increase in tumor multiplicity. This was associated with more advanced dysplasia, including progression to invasive adenocarcinoma, and augmented intratumoral proliferation. Analysis of ChIP-seq datasets for MTGR1 and MTG16 targets indicated that MTGR1 can regulate Wnt and Notch signaling. In support of this, immunohistochemistry and gene expression analysis revealed that both Wnt and Notch signaling pathways were hyperactive in Mtgr1−/− tumors. Furthermore, in human colorectal cancer (CRC) samples MTGR1 was downregulated at both the transcript and protein level. Overall our data indicates that MTGR1 has a context dependent effect on intestinal tumorigenesis. PMID:27270437

  12. [Bacterial Translocation from Intestine: Microbiological, Immunological and Pathophysiological Aspects].

    Science.gov (United States)

    Podoprigora, G I; Kafarskaya, L I; Bainov, N A; Shkoporov, A N

    2015-01-01

    Bacterial translocation (BT) is both pathology and physiology phenomenon. In healthy newborns it accompanies the process of establishing the autochthonous intestinal microbiota and the host microbiome. In immunodeficiency it can be an aethio-pathogenetic link and a manifestation of infection or septic complications. The host colonization resistance to exogenous microbic colonizers is provided by gastrointestinal microbiota in concert with complex constitutional and adaptive defense mechanisms. BT may be result of barrier dysfunction and self-purification mechanisms involving the host myeloid cell phagocytic system and opsonins. Dynamic cell humoral response to microbial molecular patterns that occurs on the mucous membranes initiates receptorsignalingpathways and cascade ofreactions. Their vector and results are largely determined by cross-reactivity between microbiome and the host genome. Enterocyte barriers interacting with microbiota play leading role in providing adaptive, homeostatic and stress host reactivity. Microcirculatory ischemic tissue alterations and inflammatory reactions increase the intestinal barrier permeability and BT These processes a well as mechanisms for apoptotic cells and bacteria clearance are justified to be of prospective research interest. The inflammatory and related diseases caused by alteration and dysfunction of the intestinal barrier are reasonably considered as diseases of single origin. Maternal microbiota affects theformation of the innate immune system and the microbiota of the newborn, including intestinal commensal translocation during lactation. Deeper understanding of intestinal barrier mechanisms needs complex microbiological, immunological, pathophysiological, etc. investigations using adequate biomodels, including gnotobiotic animals.

  13. Translocation of the neonicotinoid seed treatment clothianidin in maize.

    Science.gov (United States)

    Alford, Adam; Krupke, Christian H

    2017-01-01

    Neonicotinoid seed treatments, typically clothianidin or thiamethoxam, are routinely applied to >80% of maize (corn) seed grown in North America where they are marketed as a targeted pesticide delivery system. Despite this widespread use, the amount of compound translocated into plant tissue from the initial seed treatment to provide protection has not been reported. Our two year field study compared concentrations of clothianidin seed treatments in maize to that of maize without neonicotinoid seed treatments and found neonicotinoids present in root tissues up to 34 days post planting. Plant-bound clothianidin concentrations followed an exponential decay pattern with initially high values followed by a rapid decrease within the first ~20 days post planting. A maximum of 1.34% of the initial seed treatment was successfully recovered from plant tissues in both study years and a maximum of 0.26% was recovered from root tissue. Our findings show neonicotinoid seed treatments may provide protection from some early season secondary maize pests. However, the proportion of the neonicotinoid seed treatment clothianidin translocated into plant tissues throughout the growing season is low overall and this observation may provide a mechanism to explain reports of inconsistent efficacy of this pest management approach and increasing detections of environmental neonicotinoids.

  14. Translocation of the neonicotinoid seed treatment clothianidin in maize.

    Directory of Open Access Journals (Sweden)

    Adam Alford

    Full Text Available Neonicotinoid seed treatments, typically clothianidin or thiamethoxam, are routinely applied to >80% of maize (corn seed grown in North America where they are marketed as a targeted pesticide delivery system. Despite this widespread use, the amount of compound translocated into plant tissue from the initial seed treatment to provide protection has not been reported. Our two year field study compared concentrations of clothianidin seed treatments in maize to that of maize without neonicotinoid seed treatments and found neonicotinoids present in root tissues up to 34 days post planting. Plant-bound clothianidin concentrations followed an exponential decay pattern with initially high values followed by a rapid decrease within the first ~20 days post planting. A maximum of 1.34% of the initial seed treatment was successfully recovered from plant tissues in both study years and a maximum of 0.26% was recovered from root tissue. Our findings show neonicotinoid seed treatments may provide protection from some early season secondary maize pests. However, the proportion of the neonicotinoid seed treatment clothianidin translocated into plant tissues throughout the growing season is low overall and this observation may provide a mechanism to explain reports of inconsistent efficacy of this pest management approach and increasing detections of environmental neonicotinoids.

  15. Novel Class of Potential Therapeutics that Target Ricin Retrograde Translocation

    Directory of Open Access Journals (Sweden)

    Veronika Redmann

    2013-12-01

    Full Text Available Ricin toxin, an A-B toxin from Ricinus communis, induces cell death through the inhibition of protein synthesis. The toxin binds to the cell surface via its B chain (RTB followed by its retrograde trafficking through intracellular compartments to the ER where the A chain (RTA is transported across the membrane and into the cytosol. Ricin A chain is transported across the ER membrane utilizing cellular proteins involved in the disposal of aberrant ER proteins by a process referred to as retrograde translocation. Given the current lack of therapeutics against ricin intoxication, we developed a high-content screen using an enzymatically attenuated RTA chimera engineered with a carboxy-terminal enhanced green fluorescent protein (RTAE177Qegfp to identify compounds that target RTA retrograde translocation. Stabilizing RTAE177Qegfp through the inclusion of proteasome inhibitor produced fluorescent peri-nuclear granules. Quantitative analysis of the fluorescent granules provided the basis to discover compounds from a small chemical library (2080 compounds with known bioactive properties. Strikingly, the screen found compounds that stabilized RTA molecules within the cell and several compounds limited the ability of wild type RTA to suppress protein synthesis. Collectively, a robust high-content screen was developed to discover novel compounds that stabilize intracellular ricin and limit ricin intoxication.

  16. Molecular determinants of nucleolar translocation of RNA helicase A

    International Nuclear Information System (INIS)

    Liu Zhe; Kenworthy, Rachael; Green, Christopher; Tang, Hengli

    2007-01-01

    RNA helicase A (RHA) is a member of the DEAH-box family of DNA/RNA helicases involved in multiple cellular processes and the life cycles of many viruses. The subcellular localization of RHA is dynamic despite its steady-state concentration in the nucleoplasm. We have previously shown that it shuttles rapidly between the nucleus and the cytoplasm by virtue of a bidirectional nuclear transport domain (NTD) located in its carboxyl terminus. Here, we investigate the molecular determinants for its translocation within the nucleus and, more specifically, its redistribution from the nucleoplasm to nucleolus or the perinucleolar region. We found that low temperature treatment, transcription inhibition or replication of hepatitis C virus caused the intranuclear redistribution of the protein, suggesting that RHA shuttles between the nucleolus and nucleoplasm and becomes trapped in the nucleolus or the perinucleolar region upon blockade of transport to the nucleoplasm. Both the NTD and ATPase activity were essential for RHA's transport to the nucleolus or perinucleolar region. One of the double-stranded RNA binding domains (dsRBD II) was also required for this nucleolar translocation (NoT) phenotype. RNA interference studies revealed that RHA is essential for survival of cultured hepatoma cells and the ATPase activity appears to be important for this critical role

  17. Adenine nucleotide translocator transports haem precursors into mitochondria.

    Directory of Open Access Journals (Sweden)

    Motoki Azuma

    2008-08-01

    Full Text Available Haem is a prosthetic group for haem proteins, which play an essential role in oxygen transport, respiration, signal transduction, and detoxification. In haem biosynthesis, the haem precursor protoporphyrin IX (PP IX must be accumulated into the mitochondrial matrix across the inner membrane, but its mechanism is largely unclear. Here we show that adenine nucleotide translocator (ANT, the inner membrane transporter, contributes to haem biosynthesis by facilitating mitochondrial accumulation of its precursors. We identified that haem and PP IX specifically bind to ANT. Mitochondrial uptake of PP IX was inhibited by ADP, a known substrate of ANT. Conversely, ADP uptake into mitochondria was competitively inhibited by haem and its precursors, suggesting that haem-related porphyrins are accumulated into mitochondria via ANT. Furthermore, disruption of the ANT genes in yeast resulted in a reduction of haem biosynthesis by blocking the translocation of haem precursors into the matrix. Our results represent a new model that ANT plays a crucial role in haem biosynthesis by facilitating accumulation of its precursors into the mitochondrial matrix.

  18. Zinc translocation accelerates infarction after mild transient focal ischemia.

    Science.gov (United States)

    Lee, J-M; Zipfel, G J; Park, K H; He, Y Y; Hsu, C Y; Choi, D W

    2002-01-01

    Excess release of chelatable zinc (Zn(2+)) from central synaptic vesicles may contribute to the pathogenesis of selective neuronal cell death following transient forebrain ischemia, but a role in neurodegeneration after focal ischemia has not been defined. Adult male Long-Evans rats subjected to middle cerebral artery occlusion (MCAO) for 30 min followed by reperfusion developed delayed cerebral infarction reaching completion 3 days after the insult. One day after the insult, many degenerating cerebral neurons exhibited increased intracellular Zn(2+), and some labeled with the antibody against activated caspase-3. I.c.v. administration of the Zn(2+) chelator, EDTA saturated with equimolar Ca(2+) (CaEDTA), 15 min prior to ischemia attenuated subsequent Zn(2+) translocation into cortical neurons, and reduced infarct volume measured 3 days after ischemia. Although the protective effect of CaEDTA at this endpoint was substantial (about 70% infarct reduction), it was lost when insult severity was increased (from 30 to 60 min MCAO), or when infarct volume was measured at a much later time point (14 days instead of 3 days after ischemia). These data suggest that toxic Zn(2+) translocation, from presynaptic terminals to post-synaptic cell bodies, may accelerate the development of cerebral infarction following mild transient focal ischemia.

  19. Translocation of cesium in plants after foliar deposition - Experiments and models

    International Nuclear Information System (INIS)

    Proehl, G.; Voigt, G.; Mueller, H.

    1991-01-01

    The translocation of cesium from the foliage to the edible parts as function of the time period between deposition and harvest has been determined for cereals, potatoes, green beans and carrots. From the results the following conclusions can be drawn: 1. The maximum of the cesium translocation is 40 to 50 and 70 to 90 days before harvest for cereals and potatoes respectively. For green beans a maximum was observed after deposition 15 days before harvest; 2. The variations of the translocation factors are less if the translocation is normalized to the yield; 3. The translocation factors are in good agreement with those of other investigators. The agreement between the experimental series is better for a normalization of the translocation factor on the yield; 4. For cereals and potatoes the translocation can be described with gaussian functions which are consistent with the physiological development of cereals and potatoes. Although the approach in ECOSYS tends to over predict slightly the translocation for barley and potatoes there is a good overall agreement between the experiments and this model; 5. According to the investigations available the translocation of cesium can be predicted within a factor of 3 for cereals and a factor of 4 for potatoes. Sources of the uncertainties besides the biological variability and the inherent experimental error are differences in the development of the plants due to weather conditions, farm management and plant diseases. (9 refs., 5 figs.)

  20. Efficient secretion of small proteins in mammalian cells relies on Sec62-dependent posttranslational translocation

    Science.gov (United States)

    Lakkaraju, Asvin K. K.; Thankappan, Ratheeshkumar; Mary, Camille; Garrison, Jennifer L.; Taunton, Jack; Strub, Katharina

    2012-01-01

    Mammalian cells secrete a large number of small proteins, but their mode of translocation into the endoplasmic reticulum is not fully understood. Cotranslational translocation was expected to be inefficient due to the small time window for signal sequence recognition by the signal recognition particle (SRP). Impairing the SRP pathway and reducing cellular levels of the translocon component Sec62 by RNA interference, we found an alternate, Sec62-dependent translocation path in mammalian cells required for the efficient translocation of small proteins with N-terminal signal sequences. The Sec62-dependent translocation occurs posttranslationally via the Sec61 translocon and requires ATP. We classified preproteins into three groups: 1) those that comprise ≤100 amino acids are strongly dependent on Sec62 for efficient translocation; 2) those in the size range of 120–160 amino acids use the SRP pathway, albeit inefficiently, and therefore rely on Sec62 for efficient translocation; and 3) those larger than 160 amino acids depend on the SRP pathway to preserve a transient translocation competence independent of Sec62. Thus, unlike in yeast, the Sec62-dependent translocation pathway in mammalian cells serves mainly as a fail-safe mechanism to ensure efficient secretion of small proteins and provides cells with an opportunity to regulate secretion of small proteins independent of the SRP pathway. PMID:22648169

  1. Use of wild–caught individuals as a key factor for success in vertebrate translocations

    Energy Technology Data Exchange (ETDEWEB)

    Rummel, L.; MartInez-AbraIn, A.; Mayol, J.; Ruiz-Olmo, J.; Mañas, F.; Jimenez, J.; Gomez, J.A.; Oro, D.

    2016-07-01

    Success of vertebrate translocations is crucial to improve efficacy and efficiency of conservation actions but it is often difficult to assess because negative results (failed translocations) are seldom published. We developed surveys and sent them to heads of conservation services in three major Spanish Mediterranean regions. The purpose of our surveys was to determine which methodological factor, that could easily be implemented in practice, was more influential for translocation success. These factors included the origin of translocated individuals (captive or wild) and translocation effort (propagule size and program duration). After analyzing 83 programs, corresponding to 34 different vertebrate species, by means of generalized linear mixed modelling, we found that ‘origin’ was more relevant for translocation success than ‘effort’, although we could not rule out some role of translocation effort. Variance in success of translocation programs involving individuals from wild sources was smaller and consequently results more predictable. Origin interacted with taxa so that success was higher when using wild birds and especially wild fish and mammals, but not when releasing reptiles. Hence, we suggest that, for any given effort, translocation results will be better for most vertebrate taxa if individuals from wild sources are used. When this is not feasible, managers should release captive–reared individuals for a long number of years rather than a short number of years. (Author)

  2. Can Characteristics of Reciprocal Translocations Predict the Chance of Transferable Embryos in PGD Cycles?

    Directory of Open Access Journals (Sweden)

    Elsbeth Dul

    2014-04-01

    Full Text Available Translocation carriers have an increased risk of miscarriage or the birth of a child with congenital anomalies. Preimplantation genetic diagnosis (PGD is performed in translocation carriers to select for balanced embryos and, thus, increase the chance of an ongoing pregnancy. However, a common experience is that reciprocal translocation carriers produce a high percentage of unbalanced embryos, which cannot be transferred. Therefore, the pregnancy rates in PGD in this patient group are low. In a cohort of 85 reciprocal translocation carriers undergoing PGD we have searched for cytogenetic characteristics of the translocations that can predict the percentage of balanced embryos. Using shape algorithms, the most likely segregation mode per translocation was determined. Shape algorithm, breakpoint location, and relative chromosome segment sizes proved not to be independent predictors of the percentage of balanced embryos. The ratio of the relative sizes of the translocated segments of both translocation chromosomes can give some insight into the chance of transferable embryos: Very asymmetrical translocations have a higher risk of unbalanced products (p = 0.048. Counseling of the couples on the pros and cons of all their reproductive options remains very important.

  3. Use of wild–caught individuals as a key factor for success in vertebrate translocations

    Directory of Open Access Journals (Sweden)

    Rummel, L.

    2016-06-01

    Full Text Available Success of vertebrate translocations is crucial to improve efficacy and efficiency of conservation actions but it is often difficult to assess because negative results (failed translocations are seldom published. We developed surveys and sent them to heads of conservation services in three major Spanish Mediterranean regions. The purpose of our surveys was to determine which methodological factor, that could easily be implemented in practice, was more influential for translocation success. These factors included the origin of translocated individuals (captive or wild and translocation effort (propagule size and program duration. After analyzing 83 programs, corresponding to 34 different vertebrate species, by means of generalized linear mixed modelling, we found that ‘origin’ was more relevant for translocation success than ‘effort’, although we could not rule out some role of translocation effort. Variance in success of translocation programs involving individuals from wild sources was smaller and consequently results more predictable. Origin interacted with taxa so that success was higher when using wild birds and especially wild fish and mammals, but not when releasing reptiles. Hence, we suggest that, for any given effort, translocation results will be better for most vertebrate taxa if individuals from wild sources are used. When this is not feasible, managers should release captive–reared individuals for a long number of years rather than a short number of years.

  4. Translocation of reindeer from South Georgia to the Falkland Islands

    Directory of Open Access Journals (Sweden)

    Cameron M. Bell

    2010-03-01

    Full Text Available This report describes the first translocation of reindeer Rangifer tarandus from South Georgia to the Falkland Islands, in the South Atlantic Ocean. Reindeer were introduced from Norway to the subantarctic island of South Georgia on three occasions in the early 1900s by Norwegian whalers, and today they exist as two discrete herds, numbering approximately 2600 individuals in total. Because of concerns over the impact on native vegetation, the long-term eradication of reindeer from South Georgia has recently been proposed. A translocation of reindeer to the Falkland Islands was undertaken in 2001 by the Falkland Island Government with two objectives: (1 to preserve the genetic resources of at least one of the South Georgia herds; and (2 to facilitate the diversification of the agricultural sector of the Falkland Islands by establishing a commercial reindeer herd. Techniques developed and used in North America for the successful relocation of large numbers of calves were adopted for the translocation. A total of 59 calves (26 females and 33 males were successfully translocated from South Georgia to the Falklands Islands in 2001, and subsequently produced their first offspring in 2003. Good husbandry practices and an understanding of biology and behaviour are essential for the successful translocation of reindeer.Flytting av rein fra Sør-Georgia til FalklandsøyeneAbstract in Norwegian / Sammendrag: Artikkelen beskriver den første overføring av rein Rangifer tarandus fra Sør-Georgia til Falklandsøyene i søratlanteren. Tamrein fra Norge ble flyttet til den subarktiske øya Sør-Georgia ved tre anledninger i perioden 1911 til 1925 i forbindelse med den norske hvalfangsten der. I dag består bestanden av rundt regnet 2600 dyr fordelt på to geografisk atskilte flokker. Av hensyn til den naturlige vegetasjonen på øya er det forslag om å på sikt utrydde reinbestanden på øya. Regjeringen på Falklandsøyene foretok en første overføring av

  5. Photoreactivating enzyme from Escherichia coli

    International Nuclear Information System (INIS)

    Snapka, R.M.; Fuselier, C.O.

    1977-01-01

    Escherichia coli photoreactivating enzyme (PRE) has been purified in large amounts from an E.coli strain lysogenic for a defective lambda bacteriophage carrying the phr gene. The resulting enzyme had a pH optimum of 7.2 and an ionic strength optimum of 0.18. It consisted of an apoprotein and cofactor, both of which were necessary for catalytic activity. The apoprotein had a monomer molecular weight of 35,200 and showed stable aggregates under denaturing conditions. The amino acid analysis of the E.coli enzyme was very similar to that of the photoreactivating enzyme from orchid seedlings (Cattelya aurantiaca). Both had arginine at the amino terminus. The cofactor, like the holoenzyme, showed absorption, magnetic circular dichroism, and emission properties indicative of an adenine moiety. Although the isolated enzyme had an action spectrum which peaked at about 360 nm, neither the cofactor, apoenzyme nor holoenzyme showed any detectable absorption between 300 and 400 nm. (author)

  6. Photoreactivating enzyme from Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Snapka, R M; Fuselier, C O [California Univ., Irvine (USA)

    1977-05-01

    Escherichia coli photoreactivating enzyme (PRE) has been purified in large amounts from an E.coli strain lysogenic for a defective lambda bacteriophage carrying the phr gene. The resulting enzyme had a pH optimum of 7.2 and an ionic strength optimum of 0.18. It consisted of an apoprotein and cofactor, both of which were necessary for catalytic activity. The apoprotein had a monomer molecular weight of 35,200 and showed stable aggregates under denaturing conditions. The amino acid analysis of the E.coli enzyme was very similar to that of the photoreactivating enzyme from orchid seedlings (Cattelya aurantiaca). Both had arginine at the amino terminus. The cofactor, like the holoenzyme, showed absorption, magnetic circular dichroism, and emission properties indicative of an adenine moiety. Although the isolated enzyme had an action spectrum which peaked at about 360 nm, neither the cofactor, apoenzyme nor holoenzyme showed any detectable absorption between 300 and 400 nm.

  7. Surface display of Salmonella epitopes in Escherichia coli and Staphylococcus carnosus.

    Science.gov (United States)

    Nhan, Nguyen Thanh; Gonzalez de Valdivia, Ernesto; Gustavsson, Martin; Hai, Truong Nam; Larsson, Gen

    2011-04-11

    Salmonella enterica serotype Enteritidis (SE) is considered to be one of the most potent pathogenic Salmonella serotypes causing food-borne disease in humans. Since a live bacterial vaccine based on surface display of antigens has many advantages over traditional vaccines, we have studied the surface display of the SE antigenic proteins, H:gm and SefA in Escherichia coli by the β-autotransporter system, AIDA. This procedure was compared to protein translocation in Staphylococcus carnosus, using a staphylococci hybrid vector earlier developed for surface display of other vaccine epitopes. Both SefA and H:gm were translocated to the outer membrane in Escherichia coli. SefA was expressed to full length but H:gm was shorter than expected, probably due to a proteolytic cleavage of the N-terminal during passage either through the periplasm or over the membrane. FACS analysis confirmed that SefA was facing the extracellular environment, but this could not be conclusively established for H:gm since the N-terminal detection tag (His6) was cleaved off. Polyclonal salmonella antibodies confirmed the sustained antibody-antigen binding towards both proteins. The surface expression data from Staphylococcus carnosus suggested that the H:gm and SefA proteins were transported to the cell wall since the detection marker was displayed by FACS analysis. Apart from the accumulated knowledge and the existence of a wealth of equipment and techniques, the results indicate the selection of E. coli for further studies for surface expression of salmonella antigens. Surface expression of the full length protein facing the cell environment was positively proven by standard analysis, and the FACS signal comparison to expression in Staphylococcus carnosus shows that the distribution of the surface protein on each cell was comparatively very narrow in E. coli, the E. coli outer membrane molecules can serve as an adjuvant for the surface antigenic proteins and multimeric forms of the SefA protein

  8. Expression in E. coli systems

    DEFF Research Database (Denmark)

    Krogsdam, Anne-M; Kristiansen, Karsten; Nøhr, Jane

    2003-01-01

    intracellularly in soluble form. In E. coli, proteins containing disulfide bonds are best produced by secretion because the disulfide forming foldases reside in the periplasm. Likewise, a correct N-terminus is more likely to be obtained upon secretion. Moreover, potentially toxic proteins are more likely......Owing to cost advantage, speed of production, and often high product yield (up to 50% of total cell protein), expression in Escherichia coli is generally the first choice when attempting to express a recombinant protein. Expression systems exist to produce recombinant protein intracellularly...

  9. Experimental evolution of E. coli

    Science.gov (United States)

    Zhang, Mengshi

    The evolution from unicellular to multicellular behavior is an essential step in the history of life. Our aim is to investigate the emergence of collective behavior in the model organism Escherichia coli (E. coli) and its selection advantages, such as better utilization of public goods. Our preliminary results suggest that the evolution of collective behavior may be a natural response to stressed conditions. Mailing address: Room 306 Science Centre North Block, The Chinese University of Hong Kong, Shatin, N.T. Hong Kong SAR. Phone: +852-3943-6354. Fax: +852-2603-5204. E-mail: mengshi0928@gmail.com.

  10. The oxygen effect in E. coli cells

    International Nuclear Information System (INIS)

    Myasnik, M.N.; Skvortsov, V.G.; Sokolov, V.A.

    1982-01-01

    In experiments on E. coli strains deficient in some stages of DNA repair from radiation damages, it was demonstrated that the value of the oxygen effect, under optimal conditions for manifestation thereof, decreases in the following order: E. coli WP2 (the wild type) → E. coli WP2 exr - and E. coli B → E. coli WP2 uvr A6 → E. coli WP2 rec Al and E. coli WP2 hcr - exr - . It was detected that 0.14 M NaCl solution sensitizes the anoxic cells of some E. coli strains to the effect of γ-radiation. It was established that mutation of the uvr A-gene increases sharply the sensitivity of cells to iradiation under the anoxic conditions in the presence of NaCl, the reverse'' oxygen effect being observed

  11. [The influence of combinations of alien translocations on in vitro androgenesis in near-isogenic lines of spring bread wheat].

    Science.gov (United States)

    Sibikeeva, Yu E; Sibikeev, S N

    2014-07-01

    The features of in vitro androgenesis were studied in Cultured anthers of spring bread wheats L503 and Dobrynya, having 7DS-7DL-7Ae#1 L translocation with genes Lrl9/Sr25 (Lrl9 translocation) from Agropyron elongatum (Host.) P.B. and their near-isogenic lines carrying combinations of Lrl9 translocation with translocations: 1BL-IR#1S with genes Pm8/Sr31/Lr26/Yr9 (Lr26translocation) from Secale cereal L., 4BS-4BL-2R#1L with genes Lr25/Pm7 (Lr25 translocation) from Secale cereal, 3DS-3DL-3Ae#1L with genes Lr24/Sr24 (Lr24 translocation) from Agropyron elongatum and 6BS-6BL-6U#1L with gene Lr9 (Lr9 translocation) from Aegilops umbellulata Zhuk. In comparison with those varieties having received the Lrl9 translocation, the following was established: (1) the combination of translocations Lr19+26 increased embryo frequency and green plant regeneration; (2) the combination of translocations Lr19+9 decreased embryo frequency but increased green plant regeneration; (3) the combination of translocations Lr19+24 decreased embryo frequency but increased green and albino plant regeneration; (4) the combination of translocations Lr19+25 increased embryo frequency and green plant regeneration but decreased albino plant regeneration. Thus, on near-isogenic lines of spring bread wheat, the influences of genotypes of four alien translocation combinations on in vitro androgenesis were determined.

  12. The prognosis of MYC translocation positive diffuse large B-cell lymphoma depends on the second hit.

    Science.gov (United States)

    Clipson, Alexandra; Barrans, Sharon; Zeng, Naiyan; Crouch, Simon; Grigoropoulos, Nicholas F; Liu, Hongxiang; Kocialkowski, Sylvia; Wang, Ming; Huang, Yuanxue; Worrillow, Lisa; Goodlad, John; Buxton, Jenny; Neat, Michael; Fields, Paul; Wilkins, Bridget; Grant, John W; Wright, Penny; Ei-Daly, Hesham; Follows, George A; Roman, Eve; Watkins, A James; Johnson, Peter W M; Jack, Andrew; Du, Ming-Qing

    2015-07-01

    A proportion of MYC translocation positive diffuse large B-cell lymphomas (DLBCL) harbour a BCL2 and/or BCL6 translocation, known as double-hit DLBCL, and are clinically aggressive. It is unknown whether there are other genetic abnormalities that cooperate with MYC translocation and form double-hit DLBCL, and whether there is a difference in clinical outcome between the double-hit DLBCL and those with an isolated MYC translocation. We investigated TP53 gene mutations along with BCL2 and BCL6 translocations in a total of 234 cases of DLBCL, including 81 with MYC translocation. TP53 mutations were investigated by PCR and sequencing, while BCL2 and BCL6 translocation was studied by interphase fluorescence in situ hybridization. The majority of MYC translocation positive DLBCLs (60/81 = 74%) had at least one additional genetic hit. In MYC translocation positive DLBCL treated by R-CHOP ( n  = 67), TP53 mutation and BCL2, but not BCL6 translocation had an adverse effect on patient overall survival. In comparison with DLBCL with an isolated MYC translocation, cases with MYC/TP53 double-hits had the worst overall survival, followed by those with MYC/BCL2 double-hits. In MYC translocation negative DLBCL treated by R-CHOP ( n  = 101), TP53 mutation, BCL2 and BCL6 translocation had no impact on patient survival. The prognosis of MYC translocation positive DLBCL critically depends on the second hit, with TP53 mutations and BCL2 translocation contributing to an adverse prognosis. It is pivotal to investigate both TP53 mutations and BCL2 translocations in MYC translocation positive DLBCL, and to distinguish double-hit DLBCLs from those with an isolated MYC translocation.

  13. Experience with FISH-detected translocations as an indicator in retrospective dose reconstructions

    International Nuclear Information System (INIS)

    Pressl, S.; Romm, H.; Ganguly, B.B.; Stephan, G.

    2000-01-01

    The prerequisite for the use of translocations as an indicator in retrospective dose reconstructions, is knowledge of the background level, persistence, and the availability of dose response curves for the conversion of translocation frequencies into doses. The results obtained in these areas are summarised. Cells with complete painted chromosome material are evaluated. Those showing any aberrations which involve painted material are stored in a computerised system, and described in detail. The simultaneous painting of whole chromosomes and centromeres has proved to provide a better level of discrimination between translocations and dicentrics. Following irradiation, direct proportionality was observed between DNA content covered by the painted chromosomes (11-19%) and the translocation frequency. The background level of translocations was determined in 42 healthy subjects, aged between 21 and 73 years of age. The statistical analyses of the data revealed no influence from sex and smoking habits on the translocation frequency. A clear increase in translocation yield was, however, observed for age. For the whole genome the frequency is at a level of 3 to 11 per 1000 cells, for all types of translocations. In a radiation accident victim (Estonia) the frequency of translocations was determined over a post-exposure time of four years. For two-way translocations, the half-time was calculated to be 7.0 years, and that for one-way translocations 5.2 years. On the basis of our control data and our dose response curve, the lowest detectable radiation dose is about 0.3 Gy in subjects under 40 years of age, and about 0.5 Gy for those older than 40 years of age. (author)

  14. Translocation of iodine-129 in soil and transfer to vegetation

    International Nuclear Information System (INIS)

    Handl, J.

    1989-01-01

    The translocation of I-129 in the soil and its long-term transfer from soil to plant have been investigated using an undisturbed soil column and a pasture on a river bank. The I-129 profiles in the soils of the monolith and the pasture exhibit clear differences in the distribution of radioiodine after 52 and 47 months, respectively. At those times after surface contamination of both soil types 88% (monolith) and 66% (pasture) of the total I-129 activity were found in the top soil layer of 10 cm, indicating that translocation in the pasture soil is faster than in the monolith. Apart from soil-specific parameters this behaviour may be explained by anaerobic conditions created in the soil due to high water levels in the nearby river attecting the chemical form of iodine. The distribution of stable iodine was found rather homogeneous in both soils with mean contents of 3 mg I-127 kg -1 d.w. in the upper 15 cm and 4 mg I-127 kg -1 d.w. in deeper layers in case of the monolith. For the pasture soil the corresponding values are about 4 and 5 mg I-127 kg -1 d.w. Transfer factors plant/soil (dry weight basis) of I-129 obtained from the monolith 39 g and 52 months after contamination are 1.5x10 -3 and 2.1x10 -3 , respectively. Data from the pasture 35 and 47 months after contamination show values of 9.0x10 -3 and 8.4x10 -3 , respectively. Transfer factors of stable iodine are significantly higher in both soils yielding an average value of 1.0 for the monolith and 0.3 for the pasture. Delay constants (related to a top soil layer of 10 cm) calculated for I-129 using data obtained from the long-term translocation processes to deeper soil layers in the monolith and in the pasture show values of 1x10 -9 s -1 and 4x10 -9 s -1 , respectively. (orig.) [de

  15. Cd translocation into generative organs of linseed (Linum usitatissimum L.)

    Energy Technology Data Exchange (ETDEWEB)

    Becher, M.; Woerner, A.; Schubert, S. [Giessen Univ. (Germany). Inst. fuer Pflanzenernaehrung

    1997-12-31

    Linseed is able to accumulate considerably high concentrations of Cd in generative organs, the dietary critical value of 0.3 {mu}g Cd/g seed often being exceeded. Differences between genotypes of linseed in this respect, however, have been observed but the underlying mechanisms responsible for these differences are unknown. The aim of the present work was to identify these mechanisms by studying the Cd accumulation of the linseed genotypes Antares and McGregor which differ in their ability to accumulate Cd in the seeds. Cultivar Antares is a high and cv. McGregor is low Cd accumulator which was confirmed in a pot experiment. It was found that the differences between these genotypes were Cd-specific and were caused neither by single seed weight nor by Cd translocation into the shoot. The distribution pattern of Cd within mature capsules between the pericarp and the seeds differed from that of Ca which was used as a phloem-immobile reference ion. From these results we conclude that Cd was translocated from the pericarp into the seeds via the phloem. This conclusion was supported by direct Cd determination in collected phloem sap from linseed stems. As sources of seed-Cd we identified the pericarps of capsules and the leaves. The genotype differences concerning the Cd concentrations in the seeds may be explained in terms of differences in phloem translocation of Cd. (orig.) [Deutsch] Oellein vermag Cd in betraechtlichen Konzentrationen in den Samen zu akkumulieren. Aus diesem Grund wird der Grenzwert fuer Diaetlein von 0,3 {mu}g/g Samen im Anbau haeufig ueberschritten. Es gibt jedoch genotypische Unterschiede, deren zugrundeliegende Mechanismen nicht bekannt sind. Das Ziel der vorliegenden Arbeit bestand darin, diese Mechanismen an den Oelleinsorten Antares und McGregor zu untersuchen. Antares akkumuliert grosse, McGregor hingegen geringe Mengen Cd in den Samen. Diese Beobachtungen konnten in einem Gefaessversuch bestaetigt werden. Es wurde gezeigt, dass die

  16. Actions and advice in coli

    DEFF Research Database (Denmark)

    Knoche, Hendrik; Jamadagni, HS; Rao, PR Sheshagiri

    2015-01-01

    To improve their agricultural output, farmers require timely and contextualized information and advice. Relevant information and advice provided by trusted peers represents a promising approach. We present the considerations for the design of coli, an agricultural information network on touch scr...

  17. Infektionen mit darmpathogenen Escherichia coli.

    NARCIS (Netherlands)

    Friedrich, Alexander; Stein, Jürgen; Dignass, Axel

    2001-01-01

    E. coli ist ein wesentlicher Bestandteil der physiologischen Darmflora des Menschen. Die üblicherweise im Darm vorkommenden Kolibakterien sind apathogen und für den Menschen eher nützlich (Sonnenborn u. Greinwald 1990). Allerdings kennen wir bei dieser Bakterienspezies auch ein breites Spektrum von

  18. 76 FR 20542 - Escherichia coli

    Science.gov (United States)

    2011-04-13

    ... beef, Escherichia coli and coliphages were found in chicken, fresh pork, fresh oyster, fresh mushrooms, lettuce, chicken pot pie, biscuit dough, deli loaf, deli roasted turkey, and package roasted chicken... surfaces, and in foods such as ground beef, pork sausage, chicken, oysters, cheese, fresh mushrooms, and...

  19. ESCHERICHIA COLI AND STAPHYLOCOCCUS AUREUS

    African Journals Online (AJOL)

    DR. AMINU

    ABSTRACT. The bio-effects of the ethanol extracts from the leaf and stem of Momordica charantia were studied with the view to ascertain the medical usefulness ascribed to the plant by the locals. The plant parts, stem and leaf, revealed remarkable activity against Escherichia coli and Staphlococcus aureus. The leaves ...

  20. Conjugal Pairing in Escherichia Coli

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 13; Issue 8. Conjugal Pairing in Escherichia Coli. Joshua Lederberg. Classics Volume 13 Issue 8 August 2008 pp 793-794. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/013/08/0793-0794 ...

  1. Escherichia coli as a probiotic?

    NARCIS (Netherlands)

    Jansen, GJ; Wildeboer-Veloo, ACM; van der Waaij, D; Degener, JE

    1998-01-01

    The influence of oral treatment with a suspension of non-pathogenic Escherichia coli cells (commercially available as: Symbioflor II(R)) on the morphological composition of the gut microflora and on the systemic humoral immune response (the IgG-, IgA- and IgM-isotype) against the bacterial cells in

  2. Expression in E. coli systems

    DEFF Research Database (Denmark)

    Krogsdam, Anne-M; Kristiansen, Karsten; Nøhr, Jane

    2003-01-01

    intracellularly in soluble form. In E. coli, proteins containing disulfide bonds are best produced by secretion because the disulfide forming foldases reside in the periplasm. Likewise, a correct N-terminus is more likely to be obtained upon secretion. Moreover, potentially toxic proteins are more likely...

  3. Tailoring particle translocation via dielectrophoresis in pore channels

    Science.gov (United States)

    Tanaka, Shoji; Tsutsui, Makusu; Theodore, Hu; Yuhui, He; Arima, Akihide; Tsuji, Tetsuro; Doi, Kentaro; Kawano, Satoyuki; Taniguchi, Masateru; Kawai, Tomoji

    2016-01-01

    Understanding and controlling electrophoretic motions of nanoscopic objects in fluidic channels are a central challenge in developing nanopore technology for molecular analyses. Although progress has been made in slowing the translocation velocity to meet the requirement for electrical detections of analytes via picoampere current measurements, there exists no method useful for regulating particle flows in the transverse directions. Here, we report the use of dielectrophoresis to manipulate the single-particle passage through a solid-state pore. We created a trap field by applying AC voltage between electrodes embedded in a low-aspect-ratio micropore. We demonstrated a traffic control of particles to go through center or near side surface via the voltage frequency. We also found enhanced capture efficiency along with faster escaping speed of particles by virtue of the AC-mediated electroosmosis. This method is compatible with nanopore sensing and would be widely applied for reducing off-axis effects to achieve single-molecule identification. PMID:27527126

  4. Mitochondrial tRNA gene translocations in highly eusocial bees

    Directory of Open Access Journals (Sweden)

    Daniela Silvestre

    2006-01-01

    Full Text Available Mitochondrial gene rearrangement events, especially involving tRNA genes, have been described more frequently as more complete mitochondrial genome sequences are becoming available. In the present work, we analyzed mitochondrial tRNA gene rearrangements between two bee species belonging to the tribes Apini and Meliponini within the "corbiculate Apidae". Eleven tRNA genes are in different genome positions or strands. The molecular events responsible for each translocation are explained. Considering the high number of rearrangements observed, the data presented here contradict the general rule of high gene order conservation among closely related organisms, and also represent a powerful molecular tool to help solve questions about phylogeny and evolution in bees.

  5. Physical insights into the blood-brain barrier translocation mechanisms

    Science.gov (United States)

    Theodorakis, Panagiotis E.; Müller, Erich A.; Craster, Richard V.; Matar, Omar K.

    2017-08-01

    The number of individuals suffering from diseases of the central nervous system (CNS) is growing with an aging population. While candidate drugs for many of these diseases are available, most of these pharmaceutical agents cannot reach the brain rendering most of the drug therapies that target the CNS inefficient. The reason is the blood-brain barrier (BBB), a complex and dynamic interface that controls the influx and efflux of substances through a number of different translocation mechanisms. Here, we present these mechanisms providing, also, the necessary background related to the morphology and various characteristics of the BBB. Moreover, we discuss various numerical and simulation approaches used to study the BBB, and possible future directions based on multi-scale methods. We anticipate that this review will motivate multi-disciplinary research on the BBB aiming at the design of effective drug therapies.

  6. Translocation of labelled fertilizer nitrogen in soil columns

    International Nuclear Information System (INIS)

    Haunold, E.; Zvara, J.

    1975-01-01

    The translocation of 15 labeled ammonium and nitrate fertilizer was studied under normal weather conditions for two years in columns filled with different soils. At the end of the experimental period, which usually lasted for 9 months, between 5.9-10.3% of the ammonium fertilizer was leached out, 33.7-50.1% remained in the soil and 39.5-59.7% was lost as gas. For nitrate nitrogen the figures were: 22.6-47.3% leached out, 16.7-40% remaining in the soil, 12.7-60.0% lost as gas. The ammonium fertilizer moving through the soil interchanged with 1-13% of the soil nitrogen, the nitrate fertilizer with only 0.5-2%

  7. Real-time analysis of nitrogen translocation in plants

    International Nuclear Information System (INIS)

    Hayashi, Hiroaki

    2000-01-01

    Nitrogen absorbed by roots is transported to the leaves through xylem vessels and then retranslocated to the new leaves, such as root and storage organs through sieve tubes. It is very important to know how this nitrogen movement occurs in the plants and what mechanisms are involved in controlling this movement in order to increase the efficiency of fertilizer. In this experiments, 13 N and 15 N was used to detect the nitrogen circulation in plants, in combination with the technique for positron detection in real time and for collection of sap in sieve tubes and analysis of 15 N in it. By using 13 N, nitrogen movement from root to shoot was analyzed within 10 min after 13 N was applied to the roots. On the other hand, nitrogen retranslocation through sieve tubes was detected by the analysis of 15 N in the phloem sap over 6 hrs. All data suggest the dynamic translocation of nitrogen in rice plants. (author)

  8. Translocation of Cell Penetrating Peptide Engrafted Nanoparticles Across Skin Layers

    Science.gov (United States)

    Patlolla, Ram R; Desai, Pinaki; Belay, Kalayu; Singh, Mandip

    2010-01-01

    The objective of the current study was to evaluate the ability of cell penetrating peptides (CPP) to translocate the lipid payload into the skin layers. Fluorescent dye (DID-oil) encapsulated nano lipid crystal nanoparticles (FNLCN) were prepared using Compritol, Miglyol and DOGS-NTA-Ni lipids by hot melt homogenization technique. The FNLCN surface was coated with TAT peptide (FNLCNT) or control YKA peptide (FNLCNY) and in vitro rat skin permeation studies were performed using Franz diffusion cells. Observation of lateral skin sections obtained using cryotome with a confocal microscope demonstrated that skin permeation of FNLCNT was time dependent and after 24 h, fluorescence was observed upto a depth of 120 µm which was localized in the hair follicles and epidermis. In case of FNLCN and FNLCNY formulations fluorescence was mainly observed in the hair follicles. This observation was further supported by confocal Raman spectroscopy where higher fluorescence signal intensity was observed at 80 and 120 µm depth with FNLCNT treated skin and intensity of fluorescence peaks was in the ratio of 2:1:1 and 5:3:1 for FNLCNT, FNLCN, and FNLCNY treated skin sections, respectively. Furthermore, replacement of DID-oil with celecoxib (Cxb), a model lipophilic drug showed similar results and after 24 h, the CXBNT formulation increased the Cxb concentration in SC by 3 and 6 fold and in epidermis by 2 and 3 fold as compared to CXBN and CXBNY formulations respectively. Our results strongly suggest that CPP can translocate nanoparticles with their payloads into deeper skin layers. PMID:20413152

  9. Distribution and Translocation of 141Ce (III) in Horseradish

    Science.gov (United States)

    Guo, Xiaoshan; Zhou, Qing; Lu, Tianhong; Fang, Min; Huang, Xiaohua

    2007-01-01

    Background and Aims Rare earth elements (REEs) are used in agriculture and a large amount of them contaminate the environment and enter foods. The distribution and translocation of 141Ce (III) in horseradish was investigated in order to help understand the biochemical behaviour and toxic mechanism of REEs in plants. Method The distribution and translocation of 141Ce (III) in horseradish were investigated using autoradiography, liquid scintillation counting (LSC) and electron microscopic autoradiography (EMARG) techniques. The contents of 141Ce (III) and nutrient elements were analysed using an inductively coupled plasma-atomic emission spectrometer (ICP-AES). Results The results from autoradiography and LSC indicated that 141Ce (III) could be absorbed by horseradish and transferred from the leaf to the leaf-stalk and then to the root. The content of 141Ce (III) in different parts of horseradish was as follows: root > leaf-stalk > leaf. The uptake rates of 141Ce (III) in horseradish changed with the different organs and time. The content of 141Ce (III) in developing leaves was greater than that in mature leaves. The results from EMARG indicated that 141Ce (III) could penetrate through the cell membrane and enter the mesophyll cells, being present in both extra- and intra-cellular deposits. The contents of macronutrients in horseradish were decreased by 141Ce (III) treatment. Conclusions 141Ce (III) can be absorbed and transferred between organs of horseradish with time, and the distribution was found to be different at different growth stages. 141Ce (III) can enter the mesophyll cells via apoplast and symplast channels or via plasmodesmata. 141Ce (III) can disturb the metabolism of macronutrients in horseradish. PMID:17921527

  10. Muscle contraction increases carnitine uptake via translocation of OCTN2

    International Nuclear Information System (INIS)

    Furuichi, Yasuro; Sugiura, Tomoko; Kato, Yukio; Takakura, Hisashi; Hanai, Yoshiteru; Hashimoto, Takeshi; Masuda, Kazumi

    2012-01-01

    Highlights: ► Muscle contraction augmented carnitine uptake into rat hindlimb muscles. ► An increase in carnitine uptake was due to an intrinsic clearance, not blood flow. ► Histochemical analysis showed sarcolemmal OCTN2 was emphasized after contraction. ► OCTN2 protein in sarcolemmal fraction was increased in contracting muscles. -- Abstract: Since carnitine plays an important role in fat oxidation, influx of carnitine could be crucial for muscle metabolism. OCTN2 (SLC22A5), a sodium-dependent solute carrier, is assumed to transport carnitine into skeletal muscle cells. Acute regulation of OCTN2 activity in rat hindlimb muscles was investigated in response to electrically induced contractile activity. The tissue uptake clearance (CL uptake ) of L-[ 3 H]carnitine during muscle contraction was examined in vivo using integration plot analysis. The CL uptake of [ 14 C]iodoantipyrine (IAP) was also determined as an index of tissue blood flow. To test the hypothesis that increased carnitine uptake involves the translocation of OCTN2, contraction-induced alteration in the subcellular localization of OCTN2 was examined. The CL uptake of L-[ 3 H]carnitine in the contracting muscles increased 1.4–1.7-fold as compared to that in the contralateral resting muscles (p uptake of [ 14 C]IAP was much higher than that of L-[ 3 H]carnitine, but no association between the increase in carnitine uptake and blood flow was obtained. Co-immunostaining of OCTN2 and dystrophin (a muscle plasma membrane marker) showed an increase in OCTN2 signal in the plasma membrane after muscle contraction. Western blotting showed that the level of sarcolemmal OCTN2 was greater in contracting muscles than in resting muscles (p < 0.05). The present study showed that muscle contraction facilitated carnitine uptake in skeletal muscles, possibly via the contraction-induced translocation of its specific transporter OCTN2 to the plasma membrane.

  11. Most Uv-Induced Reciprocal Translocations in SORDARIA MACROSPORA Occur in or near Centromere Regions.

    Science.gov (United States)

    Leblon, G; Zickler, D; Lebilcot, S

    1986-02-01

    In fungi, translocations can be identified and classified by the patterns of ascospore abortion in asci from crosses of rearrangement x normal sequence. Previous studies of UV-induced rearrangements in Sordaria macrospora revealed that a major class (called type III) appeared to be reciprocal translocations that were anomalous in producing an unexpected class of asci with four aborted ascospores in bbbbaaaa linear sequence (b = black; a = abortive). The present study shows that the anomalous type III rearrangements are, in fact, reciprocal translocations having both breakpoints within or adjacent to centromeres and that bbbbaaaa asci result from 3:1 disjunction from the translocation quadrivalent.-Electron microscopic observations of synaptonemal complexes enable centromeres to be visualized. Lengths of synaptonemal complexes lateral elements in translocation quadrivalents accurately reflect chromosome arm lengths, enabling breakpoints to be located reliably in centromere regions. All genetic data are consistent with the behavior expected of translocations with breakpoints at centromeres.-Two-thirds of the UV-induced reciprocal translocations are of this type. Certain centromere regions are involved preferentially. Among 73 type-III translocations, there were but 13 of the 21 possible chromosome combinations and 20 of the 42 possible combinations of chromosome arms.

  12. Comparative study of the reciprocal translocation rate in spermatocytes after irradiation of newborn and adult mice

    International Nuclear Information System (INIS)

    Pomerantseva, M.D.

    1978-01-01

    The yield of reciprocal translocations was investigated in spermatocytes of the CBA male mice irradiated immediately after their brith or after the irradiation of the stem spermatogonia at the age of 3 months. The irradiation doses were 100, 200, 400 R X-rays 300 R gamma-rays 60 Co. The yield of translocations in both groups was the same

  13. ESX-1-mediated translocation to the cytosol controls virulence of mycobacteria

    KAUST Repository

    Houben, Diane; Demangel, Caroline; Van Ingen, Jakko; Perez, Jorge; Baldeó n, Lucy R.; Abdallah, Abdallah; Caleechurn, Laxmee; Bottai, Daria; Van Zon, Maaike; De Punder, Karin; Van Der Laan, Tridia; Kant, Arie; Bossers-De Vries, Ruth; Willemsen, Peter Th J; Bitter, Wilbert M.; Van Soolingen, Dick; Brosch, Roland; Van Der Wel, Nicole N.; Peters, Peter J.

    2012-01-01

    Mycobacterium species, including Mycobacterium tuberculosis and Mycobacterium leprae, are among the most potent human bacterial pathogens. The discovery of cytosolic mycobacteria challenged the paradigm that these pathogens exclusively localize within the phagosome of host cells. As yet the biological relevance of mycobacterial translocation to the cytosol remained unclear. In this current study we used electron microscopy techniques to establish a clear link between translocation and mycobacterial virulence. Pathogenic, patient-derived mycobacteria species were found to translocate to the cytosol, while non-pathogenic species did not. We were further able to link cytosolic translocation with pathogenicity by introducing the ESX-1 (type VII) secretion system into the non-virulent, exclusively phagolysosomal Mycobacterium bovis BCG. Furthermore, we show that translocation is dependent on the C-terminus of the early-secreted antigen ESAT-6. The C-terminal truncation of ESAT-6 was shown to result in attenuation in mice, again linking translocation to virulence. Together, these data demonstrate the molecular mechanism facilitating translocation of mycobacteria. The ability to translocate from the phagolysosome to the cytosol is with this study proven to be biologically significant as it determines mycobacterial virulence. © 2012 Blackwell Publishing Ltd.

  14. Comparative sensitivity of photosynthesis and translocation to sulfur dioxide damage in Phaseolus vulgaris L

    International Nuclear Information System (INIS)

    Noyes, R.D.

    1978-01-01

    The inhibiting effect of sulfur dioxide on photosynthesis in a mature bean leaf and, simultaneously, on the rate of carbohydrate translocation from this same leaf has been examined. The results show a reduction of 0, 13, and 73% in net photosynthesis and 39, 44, and 69% in translocation, at concentrations of 0.1, 1, and 3 ppm sulfur dioxide, respectively. The inhibition of translocation at 0.1 ppm sulfur dioxide without any accompanying inhibition of net photosynthesis indicates that translocation is considerably more sensitive to sulfur dioxide damage. The mechanism of translocation inhibition at 1 ppm sulfur dioxide or less is shown to be independent of photosynthetic inhibition. Whereas, it is suggested that at higher concentrations significant inhibition of photosynthesis causes an additive reduction of translocation due to reduced levels of transport sugars. Autoradiograms of 14 C-labeled source leaves indicate that one possible mechanism of sulfur dioxide damage to translocation is the inhibition of sieve-tube loading. Inhibition of phloem translocation at common ambient levels (0.1 ppm) of sulfur dioxide is important to the overall growth and yield of major agricultural crops sensitive to sulfur dioxide

  15. Live birth from a patient with a three-way balanced translocation t(5 ...

    African Journals Online (AJOL)

    Objectives: Array comparative genomic hybridisation (array-CGH) was used to screen embryos for chromosome imbalances. Methods: Embryo biopsy, preimplantation genetic diagnosis using a 24sure+ kit to detect translocations in embryos. Results: Of 10 embryos tested, 2 were found to have an unbalanced translocation, ...

  16. ESX-1-mediated translocation to the cytosol controls virulence of mycobacteria

    KAUST Repository

    Houben, Diane

    2012-05-08

    Mycobacterium species, including Mycobacterium tuberculosis and Mycobacterium leprae, are among the most potent human bacterial pathogens. The discovery of cytosolic mycobacteria challenged the paradigm that these pathogens exclusively localize within the phagosome of host cells. As yet the biological relevance of mycobacterial translocation to the cytosol remained unclear. In this current study we used electron microscopy techniques to establish a clear link between translocation and mycobacterial virulence. Pathogenic, patient-derived mycobacteria species were found to translocate to the cytosol, while non-pathogenic species did not. We were further able to link cytosolic translocation with pathogenicity by introducing the ESX-1 (type VII) secretion system into the non-virulent, exclusively phagolysosomal Mycobacterium bovis BCG. Furthermore, we show that translocation is dependent on the C-terminus of the early-secreted antigen ESAT-6. The C-terminal truncation of ESAT-6 was shown to result in attenuation in mice, again linking translocation to virulence. Together, these data demonstrate the molecular mechanism facilitating translocation of mycobacteria. The ability to translocate from the phagolysosome to the cytosol is with this study proven to be biologically significant as it determines mycobacterial virulence. © 2012 Blackwell Publishing Ltd.

  17. Preimplantation genetic diagnosis by fluorescence in situ hybridization of reciprocal and Robertsonian translocations

    Directory of Open Access Journals (Sweden)

    Chun-Kai Chen

    2014-03-01

    Conclusion: There is a trend whereby the outcome for Robertsonian translocation group carriers is better than that for reciprocal translocation group carriers. Aneuploidy screening may possibly be added in order to improve the outcome, especially for individuals with an advanced maternal age. The emergence of an array-based technology should help improve this type of analysis.

  18. CHROMOSOMAL SUBLOCALIZATION OF THE 2 13 TRANSLOCATION BREAKPOINT IN ALVEOLAR RHABDOMYOSARCOMA

    NARCIS (Netherlands)

    SHAPIRO, DN; VALENTINE, MB; SUBLETT, JE; SINCLAIR, AE; TEREBA, AM; SCHEFFER, H; BUYS, CHCM; LOOK, AT

    A characteristic balanced reciprocal chromosomal translocation [t(2;13)(q35;q14)] has been identified in more than 50% of alveolar rhabdomyosarcomas. As the first step in characterization of the genes involved in this translocation, we constructed somatic cell hybrids that retained either the

  19. Comparison of experimentally determined translocation of 134Cs in potatoes with the radioecological code CHECOSYS

    International Nuclear Information System (INIS)

    Riesen, T.; Egli, J.; Andres, R.

    1997-01-01

    The verification and adoption of radioecological models is a continuous process. Greenhouse trials on the translocation of radiocaesium from leaves to potato tubers showed a 4-12 times higher translocation rate compared to the radioecological code CHECOSYS. The possible reasons for the differences are discussed. (author) 1 tab., 3 refs

  20. Analysis of 1;17 translocation breakpoints in neuroblastoma: implications for mapping of neuroblastoma genes

    NARCIS (Netherlands)

    van Roy, N.; Laureys, G.; van Gele, M.; Opdenakker, G.; Miura, R.; van der Drift, P.; Chan, A.; Versteeg, R.; Speleman, F.

    1997-01-01

    Deletions and translocations resulting in loss of distal 1p-material are known to occur frequently in advanced neuroblastomas. Fluorescence in situ hybridisation (FISH) showed that 17q was most frequently involved in chromosome 1p translocations. A review of the literature shows that 10 of 27 cell

  1. Translocations of chromosome end-segments and facultative heterochromatin promote meiotic ring formation in evening primroses.

    Science.gov (United States)

    Golczyk, Hieronim; Massouh, Amid; Greiner, Stephan

    2014-03-01

    Due to reciprocal chromosomal translocations, many species of Oenothera (evening primrose) form permanent multichromosomal meiotic rings. However, regular bivalent pairing is also observed. Chiasmata are restricted to chromosomal ends, which makes homologous recombination virtually undetectable. Genetic diversity is achieved by changing linkage relations of chromosomes in rings and bivalents via hybridization and reciprocal translocations. Although the structural prerequisite for this system is enigmatic, whole-arm translocations are widely assumed to be the mechanistic driving force. We demonstrate that this prerequisite is genome compartmentation into two epigenetically defined chromatin fractions. The first one facultatively condenses in cycling cells into chromocenters negative both for histone H3 dimethylated at lysine 4 and for C-banding, and forms huge condensed middle chromosome regions on prophase chromosomes. Remarkably, it decondenses in differentiating cells. The second fraction is euchromatin confined to distal chromosome segments, positive for histone H3 lysine 4 dimethylation and for histone H3 lysine 27 trimethylation. The end-segments are deprived of canonical telomeres but capped with constitutive heterochromatin. This genomic organization promotes translocation breakpoints between the two chromatin fractions, thus facilitating exchanges of end-segments. We challenge the whole-arm translocation hypothesis by demonstrating why reciprocal translocations of chromosomal end-segments should strongly promote meiotic rings and evolution toward permanent translocation heterozygosity. Reshuffled end-segments, each possessing a major crossover hot spot, can furthermore explain meiotic compatibility between genomes with different translocation histories.

  2. Involvement of protein kinase C in the mechanism of action of Escherichia coli heat-stable enterotoxin (STa) in a human colonic carcinoma cell line, COLO-205

    International Nuclear Information System (INIS)

    Gupta, Dyuti Datta; Saha, Subhrajit; Chakrabarti, Manoj K.

    2005-01-01

    The present study was undertaken to determine the involvement of calcium-protein kinase C pathway in the mechanism of action of Escherichia coli heat stable enterotoxin (STa) apart from STa-induced activation of guanylate cyclase in human colonic carcinoma cell line COLO-205, which was used as a model cultured cell line to study the mechanism of action of E. coli STa. In response to E. coli STa, protein kinase C (PKC) activity was increased in a time-dependent manner with its physical translocation from cytosol to membrane. Inhibition of the PKC activity in membrane fraction and inhibition of its physical translocation in response to IP 3 -mediated calcium release inhibitor dantrolene suggested the involvement of intracellular store depletion in the regulation of PKC activity. Among different PKC isoforms, predominant involvement of calcium-dependent protein kinase C (PKCα) was specified using isotype-specific pseudosubstrate, which showed pronounce enzyme activity. Inhibition of enzyme activity by PKCα-specific inhibitor Goe6976 and immunoblott study employing isotype-specific antibody further demonstrated the involvement of calcium-dependent isoform of PKC in the mechanism of action of E. coli STa. Moreover, inhibition of guanylate cyclase activity by PKCα-specific inhibitor Goe6976 suggested the involvement of PKCα in the regulation of guanylate cyclase activity

  3. Meiotic chromosomal translocations in male mice induced by X-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Savkovic, N.; Pecevski; Vuksanovic, L.; Radivojevic, D.; Alavantic, D.

    1983-01-01

    The dose-response curve for reciprocal translocations induced by acute exposure of spermatogonial stem cells to X-rays in treated mice and their F-1 sons was examined. Male mice were totally irradiated with doses of 1Gy;5x1Gy and 5Gy. The obtained results show that frequency of the chromosomal translocations in directly treated animals is dose dependent. The percentage of animals irradiated with 1Gy which had the chromosomal translocations was 60, while this percentage in animals irradiated with single and fractionated dose of 5Gy was 100. The frequency of chromosomal translocations varies from 1.5% to 8.0%. Multivalent configurations in F-1 males were observed after exposure to 5Gy only. The incidence of F-1 translocated males was 17.5%.

  4. Translocation of 14C in adventitiously rooting Calluna vulgaris on peat

    International Nuclear Information System (INIS)

    Wallen, B.

    1983-01-01

    Seasonal variation in translocation of 14 C-labelled assimilates showed that 14 C-translocation within woody tissue was mainly limited to the phytomass produced during the last eight years. Independent of overgrowth of basal stem segments or decumbent sections by Sphagnum, or of subsequent adventitious rooting, the allocation followed a negative exponential from the assimilating units down the plant, and reached negligible values in 8-yr-old wood. Translocation to fine roots was however, mainly restricted to the shallow roots. Already at ca. 10 cm depth, the fine roots contained only about 5% of the concentration in the fine roots in the surface. During spring and autumn translocation to below ground parts dominated. During summer the main translocation was within the above ground green shoots and flowers. Here most of the allocated 14 C was irreversibly bound. There were only weak indications of accumulation of moblie 14 C-compounds in the woody parts near the soil surface. (author)

  5. Unraveling the relationship between microbial translocation and systemic immune activation in HIV infection

    Science.gov (United States)

    Shan, Liang; Siliciano, Robert F.

    2014-01-01

    Chronic immune activation is a key factor in HIV-1 disease progression. The translocation of microbial products from the intestinal lumen into the systemic circulation occurs during HIV-1 infection and is associated closely with immune activation; however, it has not been determined conclusively whether microbial translocation drives immune activation or occurs as a consequence of HIV-1 infection. In an important study in this issue of the JCI, Kristoff and colleagues describe the role of microbial translocation in producing immune activation in an animal model of HIV-1 infection, SIV infection of pigtailed macaques. Blocking translocation of intestinal bacterial LPS into the circulation dramatically reduced T cell activation and proliferation, production of proinflammatory cytokines, and plasma SIV RNA levels. This study directly demonstrates that microbial translocation promotes the systemic immune activation associated with HIV-1/SIV infection. PMID:24837427

  6. Human Meningitis-Associated Escherichia coli

    Science.gov (United States)

    KIM, KWANG SIK

    2016-01-01

    E. coli is the most common Gram-negative bacillary organism causing meningitis and E. coli meningitis continues to be an important cause of mortality and morbidity throughout the world. Our incomplete knowledge of its pathogenesis contributes to such mortality and morbidity. Recent reports of E. coli strains producing CTX-M-type or TEM-type extended-spectrum β-lactamases create a challenge. Studies using in vitro and in vivo models of the blood-brain barrier have shown that E. coli meningitis follows a high-degree of bacteremia and invasion of the blood-brain barrier. E. coli invasion of the blood-brain barrier, the essentials step in the development of E. coli meningitis, requires specific microbial and host factors as well as microbe- and host-specific signaling molecules. Blockade of such microbial and host factors contributing to E. coli invasion of the blood-brain barrier is shown to be efficient in preventing E. coli penetration into the brain. The basis for requiring a high-degree of bacteremia for E. coli penetration of the blood-brain barrier, however, remains unclear. Continued investigation on the microbial and host factors contributing to a high-degree of bacteremia and E. coli invasion of the blood-brain barrier is likely to identify new targets for prevention and therapy of E. coli meningitis. PMID:27223820

  7. Copper Homeostasis in Escherichia coli and Other Enterobacteriaceae.

    Science.gov (United States)

    Rensing, Christopher; Franke, Sylvia

    2007-04-01

    An interesting model for studying environmental influences shaping microbial evolution is provided by a multitude of copper resistance and copper homeostasis determinants in enteric bacteria. This review describes these determinants and tries to relate their presence to the habitat of the respective organism, as a current hypothesis predicts that the environment should determine an organism's genetic makeup. In Escherichia coli there are four regulons that are induced in the presence of copper. Two, the CueR and the CusR regulons, are described in detail. A central component regulating intracellular copper levels, present in all free-living enteric bacteria whose genomes have so far been sequenced, is a Cu(I)translocating P-type ATPase. The P-type ATPase superfamily is a ubiquitous group of proteins involved in the transport of charged substrates across biological membranes. Whereas some components involved in copper homeostasis can be found in both anaerobes and aerobes, multi-copper oxidases (MCOs) implicated in copper tolerance in E. coli, such as CueO and the plasmid-based PcoA, can be found only in aerobic organisms. Several features indicate that CueO, PcoA, and other related MCOs are specifically adapted to combat copper-mediated oxidative damage. In addition to these well-characterized resistance operons, there are numerous other genes that appear to be involved in copper binding and trafficking that have not been studied in great detail. SilE and its homologue PcoE, for example, are thought to effect the periplasmic binding and sequestration of silver and copper, respectively.

  8. Dose-response curve for translocation frequency with single pair of painted chromosome. A comparison with dicentric and micronuclei frequency

    Energy Technology Data Exchange (ETDEWEB)

    Venkatachalam, P.; Paul, S.F.D.; Mohankumar, M.N.; Prabhu, B.K.; Gajendiran, N.; Jeevanram, R.K

    2000-07-01

    A translocation dose-response curve using a single pair of painted chromosomes was constructed. The translocation frequencies observed at different doses were compared to those obtained for dicentrics (DC) and micronuclei (MN). The translocation and DC frequency followed the Poisson distribution and MN showed over-dispersion. The translocation and DC frequencies were nearly the same for each dose point. Micronuclei showed a comparatively lower frequency. The alpha/beta ratio for translocations (0.916) and DC (0.974) were comparable, whereas the value for MN (1.526) was much higher. The equal frequencies of translocations and DC observed for a given dose indicated that genomic translocation frequency estimated using a single pair of painted chromosomes provides a reliable and easy method to measure translocation frequency. (autho000.

  9. Dose-response curve for translocation frequency with single pair of painted chromosome. A comparison with dicentric and micronuclei frequency

    International Nuclear Information System (INIS)

    Venkatachalam, P.; Paul, S.F.D.; Mohankumar, M.N.; Prabhu, B.K.; Gajendiran, N.; Jeevanram, R.K.

    2000-01-01

    A translocation dose-response curve using a single pair of painted chromosomes was constructed. The translocation frequencies observed at different doses were compared to those obtained for dicentrics (DC) and micronuclei (MN). The translocation and DC frequency followed the Poisson distribution and MN showed over-dispersion. The translocation and DC frequencies were nearly the same for each dose point. Micronuclei showed a comparatively lower frequency. The alpha/beta ratio for translocations (0.916) and DC (0.974) were comparable, whereas the value for MN (1.526) was much higher. The equal frequencies of translocations and DC observed for a given dose indicated that genomic translocation frequency estimated using a single pair of painted chromosomes provides a reliable and easy method to measure translocation frequency. (author)

  10. Bladder instillation of Escherichia coli lipopolysaccharide alters the muscle contractions in rat urinary bladder via a protein kinase C-related pathway

    International Nuclear Information System (INIS)

    Weng, T.I.; Chen, W.J.; Liu, S.H.

    2005-01-01

    Uropathogenic Escherichia coli is a common cause of urinary tract infection. We determined the effects of intravesical instillation of E. coli lipopolysaccharide (LPS, endotoxin) on muscle contractions, protein kinase C (PKC) translocation, and inducible nitric oxide synthase (iNOS) expression in rat urinary bladder. The contractions of the isolated rat detrusor muscle evoked by electrical field stimulations were measured short-term (1 h) or long-term (24 h) after intravesical instillation of LPS. One hour after LPS intravesical instillation, bladder PKC-α translocation from cytosolic fraction to membrane fraction and endothelial (e)NOS protein was elevated, and detrusor muscle contractions were significantly increased. PKC inhibitors chelerythrine and Ro32-0432 inhibited this LPS-enhanced contractile response. Application of PKC activator β-phorbol-12,13-dibutyrate enhanced the muscle contractions. Three hours after intravesical instillation of LPS, iNOS mRNA was detected in the bladder. Immunoblotting study also demonstrated that the induction of iNOS proteins is detected in bladder in which LPS was instilled. 24 h after intravesical instillation of LPS, PKC-α translocation was impaired in the bladder; LPS did not affect PKC-δ translocation. Muscle contractions were also decreased 24 h after LPS intravesical instillation. Aminoguanidine, a selective iNOS inhibitor, blocked the decrease in PKC-α translocation and detrusor contractions induced by LPS. These results indicate that there are different mechanisms involved in the alteration of urinary bladder contractions after short-term and long-term treatment of LPS; an iNOS-regulated PKC signaling may participate in causing the inhibition of muscle contractions in urinary bladder induced by long-term LPS treatment

  11. Pneumatosis Coli Mimicking Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    Teresa Jacob

    2014-01-01

    Full Text Available Pneumatosis coli (PC is a rare condition of the gastrointestinal tract involving extraluminal gas confined within the bowel wall. We report the case of a 40-year-old gentleman presenting clinically and endoscopically with suspected colorectal cancer. In light of the patient’s red flag symptoms, and carpet of polyps seen endoscopically, surgical management by an anterior resection was performed with the patient making a successful recovery. Histological analysis of the resected specimen confirmed pneumatosis coli with no evidence of colonic neoplasia. Although PC can be an incidental finding in asymptomatic patients and considered a benign condition, it can also present as a life-threatening emergency with bowel necrosis and obstruction requiring emergency surgical intervention. Also, when PC mimics malignancy, surgical management is the most appropriate step to ensure that the diagnosis of cancer is not missed.

  12. Multiplex PCR Assay for Identification of Human Diarrheagenic Escherichia coli

    OpenAIRE

    Toma, Claudia; Lu, Yan; Higa, Naomi; Nakasone, Noboru; Chinen, Isabel; Baschkier, Ariela; Rivas, Marta; Iwanaga, Masaaki

    2003-01-01

    A multiplex PCR assay for the identification of human diarrheagenic Escherichia coli was developed. The targets selected for each category were eae for enteropathogenic E. coli, stx for Shiga toxin-producing E. coli, elt and est for enterotoxigenic E. coli, ipaH for enteroinvasive E. coli, and aggR for enteroaggregative E. coli. This assay allowed the categorization of a diarrheagenic E. coli strain in a single reaction tube.

  13. Functional expression of a human GDP-L-fucose transporter in Escherichia coli.

    Science.gov (United States)

    Förster-Fromme, Karin; Schneider, Sarah; Sprenger, Georg A; Albermann, Christoph

    2017-02-01

    To investigate the translocation of nucleotide-activated sugars from the cytosol across a membrane into the endoplasmatic reticulum or the Golgi apparatus which is an important step in the synthesis of glycoproteins and glycolipids in eukaryotes. The heterologous expression of the recombinant and codon-adapted human GDP-L-fucose antiporter gene SLC35C1 (encoding an N-terminal OmpA-signal sequence) led to a functional transporter protein located in the cytoplasmic membrane of Escherichia coli. The in vitro transport was investigated using inverted membrane vesicles. SLC35C1 is an antiporter specific for GDP-L-fucose and depending on the concomitant reverse transport of GMP. The recombinant transporter FucT1 exhibited an activity for the transport of 3 H-GDP-L-fucose with a V max of 8 pmol/min mg with a K m of 4 µM. The functional expression of SLC35C1 in GDP-L-fucose overproducing E. coli led to the export of GDP-L-fucose to the culture supernatant. The export of GDP-L-fucose by E. coli provides the opportunity for the engineering of a periplasmatic fucosylation reaction in recombinant bacterial cells.

  14. The adenomatous polyposis coli protein.

    OpenAIRE

    Näthke, I S

    1999-01-01

    Mutations in the adenomatous polyposis coli (APC) gene are associated with most colorectal cancers. The APC protein has been implicated in many aspects of tumour development. This article will discuss recent data suggesting that APC may have multiple functions in the cell. First, APC is a component of the Wnt signalling pathway; second, APC may have a role in cell migration; finally, APC may regulate proliferation and apoptosis.

  15. Muscle contraction increases carnitine uptake via translocation of OCTN2

    Energy Technology Data Exchange (ETDEWEB)

    Furuichi, Yasuro [Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa (Japan); Sugiura, Tomoko; Kato, Yukio [Faculty of Pharmacy, Kanazawa University, Kanazawa (Japan); Takakura, Hisashi [Faculty of Human Sciences, Kanazawa University, Kanazawa (Japan); Hanai, Yoshiteru [Nagoya Institute of Technology, Nagoya (Japan); Hashimoto, Takeshi [Ritsumeikan University, Kusatsu (Japan); Masuda, Kazumi, E-mail: masuda@ed.kanazawa-u.ac.jp [Faculty of Human Sciences, Kanazawa University, Kanazawa (Japan)

    2012-02-24

    Highlights: Black-Right-Pointing-Pointer Muscle contraction augmented carnitine uptake into rat hindlimb muscles. Black-Right-Pointing-Pointer An increase in carnitine uptake was due to an intrinsic clearance, not blood flow. Black-Right-Pointing-Pointer Histochemical analysis showed sarcolemmal OCTN2 was emphasized after contraction. Black-Right-Pointing-Pointer OCTN2 protein in sarcolemmal fraction was increased in contracting muscles. -- Abstract: Since carnitine plays an important role in fat oxidation, influx of carnitine could be crucial for muscle metabolism. OCTN2 (SLC22A5), a sodium-dependent solute carrier, is assumed to transport carnitine into skeletal muscle cells. Acute regulation of OCTN2 activity in rat hindlimb muscles was investigated in response to electrically induced contractile activity. The tissue uptake clearance (CL{sub uptake}) of L-[{sup 3}H]carnitine during muscle contraction was examined in vivo using integration plot analysis. The CL{sub uptake} of [{sup 14}C]iodoantipyrine (IAP) was also determined as an index of tissue blood flow. To test the hypothesis that increased carnitine uptake involves the translocation of OCTN2, contraction-induced alteration in the subcellular localization of OCTN2 was examined. The CL{sub uptake} of L-[{sup 3}H]carnitine in the contracting muscles increased 1.4-1.7-fold as compared to that in the contralateral resting muscles (p < 0.05). The CL{sub uptake} of [{sup 14}C]IAP was much higher than that of L-[{sup 3}H]carnitine, but no association between the increase in carnitine uptake and blood flow was obtained. Co-immunostaining of OCTN2 and dystrophin (a muscle plasma membrane marker) showed an increase in OCTN2 signal in the plasma membrane after muscle contraction. Western blotting showed that the level of sarcolemmal OCTN2 was greater in contracting muscles than in resting muscles (p < 0.05). The present study showed that muscle contraction facilitated carnitine uptake in skeletal muscles, possibly

  16. Uptake, translocation, and toxicity of gold nanorods in maize

    Science.gov (United States)

    Moradi Shahmansouri, Nastaran

    Nanomaterials are widely used in many different products, such as electronics, cosmetics, industrial goods, biomedical uses, and other material applications. The heavy emission of nanomaterials into the environment has motived increasing concern regarding the effects on ecosystems, food chains, and, human health. Plants can tolerate a certain amount of natural nanomaterials, but large amounts of ENMs released from a variety of industries could be toxic to plants and possibly threaten the ecosystem. Employing phytoremediation as a contamination treatment method may show promise. However a pre-requisite to successful treatment is a better understanding of the behavior and effects of nanomaterials within plant systems. This study is designed to investigate the uptake, translocation, bioavailability, and toxicity of gold nanorods in maize plants. Maize is an important food and feed crop that can be used to understand the potential hazardous effects of nanoparticle uptake and distribution in the food chain. The findings could be an important contribution to the fields of phytoremediation, agri-nanotechnology, and nanoparticle toxicity on plants. In the first experiment, hydroponically grown maize seedlings were exposed to similar doses of commercial non-coated gold nanorods in three sizes, 10x34 nm, 20x75 nm, and 40x96 nm. The three nanorod species were suspended in solutions at concentrations of 350 mg/l, 5.8 mg/l, and 14 mg/l, respectively. Maize plants were exposed to all three solutions resulting in considerably lower transpiration and wet biomass than control plants. Likewise, dry biomass was reduced, but the effect is less pronounced than that of transpiration and wet biomass. The reduced transpiration and water content, which eventually proved fatal to exposed plants, were most likely a result of toxic effect of gold nanorod, which appeared to physically hinder the root system. TEM images proved that maize plants can uptake gold particles and accumulate them in

  17. Bovine Lactoferrampin, Human Lactoferricin, and Lactoferrin 1-11 Inhibit Nuclear Translocation of HIV Integrase.

    Science.gov (United States)

    Wang, Winston Yan; Wong, Jack Ho; Ip, Denis Tsz Ming; Wan, David Chi Cheong; Cheung, Randy Chifai; Ng, Tzi Bun

    2016-08-01

    This study aimed to investigate fragments derived from human and bovine lactoferrins for ability to inhibit nuclear translocation of HIV-1 integrase. It was shown that human lactoferricin, human lactoferrin 1-11, and bovine lactoferrampin reduced nuclear distribution of HIV-1 integrase. Bovine lactoferrampin could inhibit both the activity and nuclear translocation of HIV-1 integrase. Human lactoferrampin, bovine lactoferricin, and bovine lactoferrin 1-11 had no effect on HIV-1 integrase nuclear translocation. Human lactoferrampin which inhibited the activity of integrase did not prevent its nuclear translocation. Human lactoferricin and lactoferrin 1-11 did not inhibit HIV-1 integrase nuclear translocation despite their ability to attenuate the enzyme activity. The discrepancy between the findings on reduction of HIV-1 activity and inhibition of nuclear translocation of HIV-1 integrase was due to the different mechanisms involved. A similar reasoning can also be applied to the different inhibitory potencies of the milk peptides on different HIV enzymes, i.e., nuclear translocation.

  18. Influence of the Location of Attractive Polymer-Pore Interactions on Translocation Dynamics.

    Science.gov (United States)

    Ghosh, Bappa; Chaudhury, Srabanti

    2018-01-11

    We probe the influence of polymer-pore interactions on the translocation dynamics using Langevin dynamics simulations. We investigate the effect of the strength and location of the polymer-pore interaction using nanopores that are partially charged either at the entry or the exit or on both sides of the pore. We study the change in the translocation time as a function of the strength of the polymer-pore interaction for a given chain length and under the effect of an externally applied field. Under a moderate driving force and a chain length longer than the length of the pore, the translocation time shows a nonmonotonic increase with an increase in the attractive interaction. Also, an interaction on the cis side of the pore can increase the translocation probability. In the presence of an external field and a strong attractive force, the translocation time for shorter chains is independent of the polymer-pore interaction at the entry side of the pore, whereas an interaction on the trans side dominates the translocation process. Our simulation results are rationalized by a qualitative analysis of the free energy landscape for polymer translocation.

  19. Translocation of a polymer through a nanopore across a viscosity gradient.

    Science.gov (United States)

    de Haan, Hendrick W; Slater, Gary W

    2013-04-01

    The translocation of a polymer through a pore in a membrane separating fluids of different viscosities is studied via several computational approaches. Starting with the polymer halfway, we find that as a viscosity difference across the pore is introduced, translocation will predominately occur towards one side of the membrane. These results suggest an intrinsic pumping mechanism for translocation across cell walls which could arise whenever the fluid across the membrane is inhomogeneous. Somewhat surprisingly, the sign of the preferred direction of translocation is found to be strongly dependent on the simulation algorithm: for Langevin dynamics (LD) simulations, a bias towards the low viscosity side is found while for Brownian dynamics (BD), a bias towards the high viscosity is found. Examining the translocation dynamics in detail across a wide range of viscosity gradients and developing a simple force model to estimate the magnitude of the bias, the LD results are demonstrated to be more physically realistic. The LD results are also compared to those generated from a simple, one-dimensional random walk model of translocation to investigate the role of the internal degrees of freedom of the polymer and the entropic barrier. To conclude, the scaling of the results across different polymer lengths demonstrates the saturation of the directional preference with polymer length and the nontrivial location of the maximum in the exponent corresponding to the scaling of the translocation time with polymer length.

  20. Three-dimensional genome architecture influences partner selection for chromosomal translocations in human disease.

    Directory of Open Access Journals (Sweden)

    Jesse M Engreitz

    Full Text Available Chromosomal translocations are frequent features of cancer genomes that contribute to disease progression. These rearrangements result from formation and illegitimate repair of DNA double-strand breaks (DSBs, a process that requires spatial colocalization of chromosomal breakpoints. The "contact first" hypothesis suggests that translocation partners colocalize in the nuclei of normal cells, prior to rearrangement. It is unclear, however, the extent to which spatial interactions based on three-dimensional genome architecture contribute to chromosomal rearrangements in human disease. Here we intersect Hi-C maps of three-dimensional chromosome conformation with collections of 1,533 chromosomal translocations from cancer and germline genomes. We show that many translocation-prone pairs of regions genome-wide, including the cancer translocation partners BCR-ABL and MYC-IGH, display elevated Hi-C contact frequencies in normal human cells. Considering tissue specificity, we find that translocation breakpoints reported in human hematologic malignancies have higher Hi-C contact frequencies in lymphoid cells than those reported in sarcomas and epithelial tumors. However, translocations from multiple tissue types show significant correlation with Hi-C contact frequencies, suggesting that both tissue-specific and universal features of chromatin structure contribute to chromosomal alterations. Our results demonstrate that three-dimensional genome architecture shapes the landscape of rearrangements directly observed in human disease and establish Hi-C as a key method for dissecting these effects.

  1. TDP2 suppresses chromosomal translocations induced by DNA topoisomerase II during gene transcription.

    Science.gov (United States)

    Gómez-Herreros, Fernando; Zagnoli-Vieira, Guido; Ntai, Ioanna; Martínez-Macías, María Isabel; Anderson, Rhona M; Herrero-Ruíz, Andrés; Caldecott, Keith W

    2017-08-10

    DNA double-strand breaks (DSBs) induced by abortive topoisomerase II (TOP2) activity are a potential source of genome instability and chromosome translocation. TOP2-induced DNA double-strand breaks are rejoined in part by tyrosyl-DNA phosphodiesterase 2 (TDP2)-dependent non-homologous end-joining (NHEJ), but whether this process suppresses or promotes TOP2-induced translocations is unclear. Here, we show that TDP2 rejoins DSBs induced during transcription-dependent TOP2 activity in breast cancer cells and at the translocation 'hotspot', MLL. Moreover, we find that TDP2 suppresses chromosome rearrangements induced by TOP2 and reduces TOP2-induced chromosome translocations that arise during gene transcription. Interestingly, however, we implicate TDP2-dependent NHEJ in the formation of a rare subclass of translocations associated previously with therapy-related leukemia and characterized by junction sequences with 4-bp of perfect homology. Collectively, these data highlight the threat posed by TOP2-induced DSBs during transcription and demonstrate the importance of TDP2-dependent non-homologous end-joining in protecting both gene transcription and genome stability.DNA double-strand breaks (DSBs) induced by topoisomerase II (TOP2) are rejoined by TDP2-dependent non-homologous end-joining (NHEJ) but whether this promotes or suppresses translocations is not clear. Here the authors show that TDP2 suppresses chromosome translocations from DSBs introduced during gene transcription.

  2. Leading tip drives soma translocation via forward F-actin flow during neuronal migration.

    Science.gov (United States)

    He, Min; Zhang, Zheng-hong; Guan, Chen-bing; Xia, Di; Yuan, Xiao-bing

    2010-08-11

    Neuronal migration involves coordinated extension of the leading process and translocation of the soma, but the relative contribution of different subcellular regions, including the leading process and cell rear, in driving soma translocation remains unclear. By local manipulation of cytoskeletal components in restricted regions of cultured neurons, we examined the molecular machinery underlying the generation of traction force for soma translocation during neuronal migration. In actively migrating cerebellar granule cells in culture, a growth cone (GC)-like structure at the leading tip exhibits high dynamics, and severing the tip or disrupting its dynamics suppressed soma translocation within minutes. Soma translocation was also suppressed by local disruption of F-actin along the leading process but not at the soma, whereas disrupting microtubules along the leading process or at the soma accelerated soma translocation. Fluorescent speckle microscopy using GFP-alpha-actinin showed that a forward F-actin flow along the leading process correlated with and was required for soma translocation, and such F-actin flow depended on myosin II activity. In migrating neurons, myosin II activity was high at the leading tip but low at the soma, and increasing or decreasing this front-to-rear difference accelerated or impeded soma advance. Thus, the tip of the leading process actively pulls the soma forward during neuronal migration through a myosin II-dependent forward F-actin flow along the leading process.

  3. Timing of translocation influences birth rate and population dynamics in a forest carnivore

    Science.gov (United States)

    Facka, Aaron N; Lewis, Jeffrey C.; Happe, Patricia; Jenkins, Kurt J.; Callas, Richard; Powell, Roger A.

    2016-01-01

    Timing can be critical for many life history events of organisms. Consequently, the timing of management activities may affect individuals and populations in numerous and unforeseen ways. Translocations of organisms are used to restore or expand populations but the timing of translocations is largely unexplored as a factor influencing population success. We hypothesized that the process of translocation negatively influences reproductive rates of individuals that are moved just before their birthing season and, therefore, the timing of releases could influence translocation success. Prior to reintroducing fishers (Pekania pennanti) into northern California and onto the Olympic Peninsula of Washington, we predicted that female fishers released in November and December (early) would have a higher probability of giving birth to kits the following March or April than females released in January, February, and March (late), just prior to or during the period of blastocyst implantation and gestation. Over four winters (2008–2011), we translocated 56 adult female fishers that could have given birth in the spring immediately after release. Denning rates, an index of birth rate, for females released early were 92% in California and 38% in Washington. In contrast, denning rates for females released late were 40% and 11%, in California and Washington, a net reduction in denning rate of 66% across both sites. To understand how releasing females nearer to parturition could influence population establishment and persistence, we used stochastic population simulations using three-stage Lefkovitch matrices. These simulations showed that translocating female fishers early had long-term positive influences on the mean population size and on quasi-extinction thresholds compared to populations where females were released late. The results from both empirical data and simulations show that the timing of translocation, with respect to life history events, should be considered during

  4. A voltage-gated pore for translocation of tRNA

    Energy Technology Data Exchange (ETDEWEB)

    Koley, Sandip; Adhya, Samit, E-mail: nilugrandson@gmail.com

    2013-09-13

    Highlights: •A tRNA translocating complex was assembled from purified proteins. •The complex translocates tRNA at a membrane potential of ∼60 mV. •Translocation requires Cys and His residues in the Fe–S center of RIC6 subunit. -- Abstract: Very little is known about how nucleic acids are translocated across membranes. The multi-subunit RNA Import Complex (RIC) from mitochondria of the kinetoplastid protozoon Leishmania tropica induces translocation of tRNAs across artificial or natural membranes, but the nature of the translocation pore remains unknown. We show that subunits RIC6 and RIC9 assemble on the membrane in presence of subunit RIC4A to form complex R3. Atomic Force Microscopy of R3 revealed particles with an asymmetric surface groove of ∼20 nm rim diameter and ∼1 nm depth. R3 induced translocation of tRNA into liposomes when the pH of the medium was lowered to ∼6 in the absence of ATP. R3-mediated tRNA translocation could also be induced at neutral pH by a K{sup +} diffusion potential with an optimum of 60–70 mV. Point mutations in the Cys{sub 2}–His{sub 2} Fe-binding motif of RIC6, which is homologous to the respiratory Complex III Fe–S protein, abrogated import induced by low pH but not by K{sup +} diffusion potential. These results indicate that the R3 complex forms a pore that is gated by a proton-generated membrane potential and that the Fe–S binding region of RIC6 has a role in proton translocation. The tRNA import complex of L. tropica thus contains a novel macromolecular channel distinct from the mitochondrial protein import pore that is apparently involved in tRNA import in some species.

  5. Tourette syndrome in a pedigree with a 7;18 translocation: Identification of a YAC spanning the translocation breakpoint at 18q22.3

    Energy Technology Data Exchange (ETDEWEB)

    Boghosian-Sell, L.; Overhauser, J. [Thomas Jefferson Univ., Philadelphia, PA (United States); Comings, D.E. [City of Hope Medical Center, Duarte, CA (United States)

    1996-11-01

    Tourette syndrome is a neuropsychiatric disorder characterized by the presence of multiple, involuntary motor and vocal tics. Associated pathologies include attention deficit disorder and obsessive-compulsive disorder (OCD). Extensive linkage analysis based on an autosomal dominant mode of transmission with reduced penetrance has failed to show linkage with polymorphic markers, suggesting either locus heterogeneity or a polygenic origin for Tourette syndrome. An individual diagnosed with Tourette syndrome has been described carrying a constitutional chromosome translocation. Other family members carrying the translocation exhibit features seen in Tourette syndrome including motor tics, vocal tics, and OCD. Since the disruption of specific genes by a chromosomal rearrangement can elicit a particular phenotype, we have undertaken the physical mapping of the 7;18 translocation such that genes mapping at the site of the breakpoint can be identified and evaluated for a possible involvement in Tourette syndrome. Using somatic cell hybrids retaining either the der(7) or the der(18), a more precise localization of the breakpoints on chromosomes 7 and 18 have been determined. Furthermore, physical mapping has identified two YAC clones that span the translocation breakpoint on chromosome 18 as determined by FISH. These YAC clones will be useful for the eventual identification of genes that map to chromosomes 7 and 18 at the site of the translocation. 41 refs., 3 figs., 1 tab.

  6. Synaptonemal complex analysis of X-7 translocations in male mice

    Energy Technology Data Exchange (ETDEWEB)

    Ashley, T. (Univ. of Tennessee, Knoxville); Russell, L.B.; Cacheiro, N.L.A.

    1982-01-01

    The synaptonemal complexes of surface-spread spermatocytes of mice heterozygous for one of two reciprocal translations (R3 and R5) between the X and chromosome 7 have been examined by light and electron microscopy (EM). The break points of R3 were determined to be at 70% of chromosome 7, as measured from the centromere, and at 22% of the X. Translocation quadrivalents were formed almost exclusively. The break points of R5 were at 21% of chromosome 7 as measured from the centromere, and at 83% of the X. There was little indication that the break in the X interfered with sex-chromosome synapis between the 7X and Y. Univalent Y's were not observed in R3, and only seldom observed (8-14%) in R5. However, in contrast to R3, R5 formed quadrivalents relatively rarely (20% in the EM study of 100 nuclei), and hetermorphic bivalents of 7X-Y and X7-7 quite frequently (72%). Possible causes of this high bivalent frequency are discussed. Light-microsope (LM) analysis alone was found to be inadequate for interpreting synaptic configurations (quadrivalents vs. bivalents) in R5. The LM analysis was further complicated by the occurrence of nonhomologous synapsis in the heteromorphic bivalents of R5, a phenomonon easily recognized and interpreted in the EM portion of the study.

  7. Micro-Evolution in Grasshoppers Mediated by Polymorphic Robertsonian Translocations

    Science.gov (United States)

    Colombo, Pablo C.

    2013-01-01

    This review focuses on grasshoppers that are polymorphic for Robertsonian translocations because in these organisms the clarity of meiotic figures allows the study of both chiasma distribution and the orientation of trivalents and multivalents in metaphase I. Only five species of such grasshoppers were found in the literature, and all of them were from the New World: Oedaleonotus enigma (Scudder) (Orthoptera: Acrididae), Leptysma argentina Bruner, Dichroplus pratensis Bruner, Sinipta dalmani Stål, and Cornops aquaticum Bruner. A general feature of these species (except O. enigma) is that fusion carriers suffer a marked reduction of proximal and interstitial (with respect to the centromere) chiasma frequency; this fact, along with the reduction in the number of linkage groups with the consequent loss of independent segregation, produces a marked decrease of recombination in fusion carriers. This reduction in recombination has led to the conclusion that Robertsonian polymorphic grasshopper species share some properties with inversion polymorphic species of Drosophila, such as the central-marginal pattern (marginal populations are monomorphic, central populations are highly polymorphic). This pattern might be present in D. pratensis, which is certainly the most complex Robertsonian polymorphism system in the present study. However, L. argentina and C. aquaticum do not display this pattern. This issue is open to further research. Since C. aquaticum is soon to be released in South Africa as a biological control, the latitudinal pattern found in South America may repeat there. This experiment's outcome is open and deserves to be followed. PMID:23909914

  8. [Molecular genetics in chronic myeloid leukemia with variant Ph translocation].

    Science.gov (United States)

    Wu, Wei; Li, Jian-yong; Zhu, Yu; Qiu, Hai-rong; Pan, Jin-lan; Xu, Wei; Chen, Li-juan; Shen, Yun-feng; Xue, Yong-quan

    2007-08-01

    To explore the value of fluorescence in situ hybridization (FISH) and multiplex fluorescence in situ hybridization (M-FISH) techniques in the detection of genetic changes in chronic myeloid leukemia (CML) with variant Philadelphia translocation (vPh). Cytogenetic preparations from 10 CML patients with vPh confirmed by R banding were assayed with dual color dual fusion FISH technique. If only one fusion signal was detected in interphase cells, metaphase cells were observed to determine if there were derivative chromosome 9[der (9)] deletions. Meanwhile, the same cytogenetic preparations were assayed with M-FISH technique. Of the 10 CML patients with vPh, 5 were detected with der (9) deletions by FISH technique. M-FISH technique revealed that besides the chromosome 22, chromosomes 1, 3, 5, 6, 8, 10, 11 and 17 were also involved in the vPh. M-FISH technique also detected the abnormalities which were not found with conventional cytogenetics (CC), including two never reported abnormalities. The combination of CC, FISH and M-FISH technique could refine the genetic diagnosis of CML with vPh.

  9. Movilidad y desarrollo translocal en la Nicaragua (semi-rural

    Directory of Open Access Journals (Sweden)

    Griet Steel

    2012-08-01

    Full Text Available Este artículo pretende contribuir al debate sobre los vínculos entre la movilidad y el desarrollo, explorando el concepto de desarrollo translocal. Basado en trabajo de campo en los municipios de Matiguás y Muy Muy, éste analiza cómo la movilidad da forma a las estrategias de vida de los hogares (semi-rurales en Nicaragua, y explora cómo los diferentes miembros de un hogar utilizan la movilidad física como una estrategia de vida. Argumenta que los habitantes de áreas (semi-rurales consideran distintos tipos de movimientos como estrategias importantes para establecer enlaces entre personas y lugares, y para alcanzar un mejor bienestar en su comunidad natal. Al mismo tiempo muestra cómo la movilidad se forma en una arena de poder, lo que afecta su potencial. De esta manera, este artículo contribuye a un entendimiento dinámico y multidimensional de cómo los procesos de desarrollo dan forma a – y son formados por – la movilidad y la interconectividad.

  10. Cholesterol Hydroperoxide Generation, Translocation, and Reductive Turnover in Biological Systems.

    Science.gov (United States)

    Girotti, Albert W; Korytowski, Witold

    2017-12-01

    Cholesterol is like other unsaturated lipids in being susceptible to peroxidative degradation upon exposure to strong oxidants like hydroxyl radical or peroxynitrite generated under conditions of oxidative stress. In the eukaryotic cell plasma membrane, where most of the cellular cholesterol resides, peroxidation leads to membrane structural and functional damage from which pathological states may arise. In low density lipoprotein, cholesterol and phospholipid peroxidation have long been associated with atherogenesis. Among the many intermediates/products of cholesterol oxidation, hydroperoxide species (ChOOHs) have a number of different fates and deserve special attention. These fates include (a) damage-enhancement via iron-catalyzed one-electron reduction, (b) damage containment via two-electron reduction, and (c) inter-membrane, inter-lipoprotein, and membrane-lipoprotein translocation, which allows dissemination of one-electron damage or off-site suppression thereof depending on antioxidant location and capacity. In addition, ChOOHs can serve as reliable and conveniently detected mechanistic reporters of free radical-mediated reactions vs. non-radical (e.g., singlet oxygen)-mediated reactions. Iron-stimulated peroxidation of cholesterol and other lipids underlies a newly discovered form of regulated cell death called ferroptosis. These and other deleterious consequences of radical-mediated lipid peroxidation will be discussed in this review.

  11. Uptake, translocation, and accumulation of polycyclic aromatic hydrocarbons in vegetation

    International Nuclear Information System (INIS)

    Walton, B.T.; Hoylman, A.M.

    1992-12-01

    A review of the scientific literature was conducted to determine the potential for plants to take up polycyclic aromatic hydrocarbons (PAHs) from soils and the possibility of PAH movement from soils into vegetation at waste disposal sites associated with manufactured gas plants (MGP). Studies published since 1983 are considered in conjunction with previous publications and literature reviews on PAH uptake by vegetation. These studies indicate that the extent to which sorption to roots occurs is likely to be influenced by species-specific properties of the plant, physicochemical properties of each PAH, soil properties, and biodegradation rates of the PAHs in soil. PAHs containing five or more rings may sorb to plant roots but are not expected to be translocated to foliage in other than trace quantities. Uptake of naphthalene, anthracene, and benzo[a]anthracene by roots has been reported in the literature. In addition, eight PAHs of three and four rings (acenapthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, and chrysene) were isolated from leaves and roots of four plant species collected near a coal tar disposal trench in eastern Tennessee. A total concentration of 5519 ng/g was observed for the eight PAHs in roots of lamb's quarters. Coal tar, in soil, was implicated as the source of PAHs in the four plant species

  12. Selenium uptake, translocation, assimilation and metabolic fate in plants.

    Science.gov (United States)

    Sors, T G; Ellis, D R; Salt, D E

    2005-12-01

    The chemical and physical resemblance between selenium (Se) and sulfur (S) establishes that both these elements share common metabolic pathways in plants. The presence of isologous Se and S compounds indicates that these elements compete in biochemical processes that affect uptake, translocation and assimilation throughout plant development. Yet, minor but crucial differences in reactivity and other metabolic interactions infer that some biochemical processes involving Se may be excluded from those relating to S. This review examines the current understanding of physiological and biochemical relationships between S and Se metabolism by highlighting their similarities and differences in relation to uptake, transport and assimilation pathways as observed in Se hyperaccumulator and non-accumulator plant species. The exploitation of genetic resources used in bioengineering strategies of plants is illuminating the function of sulfate transporters and key enzymes of the S assimilatory pathway in relation to Se accumulation and final metabolic fate. These strategies are providing the basic framework by which to resolve questions relating to the essentiality of Se in plants and the mechanisms utilized by Se hyperaccumulators to circumvent toxicity. In addition, such approaches may assist in the future application of genetically engineered Se accumulating plants for environmental renewal and human health objectives.

  13. Ready Experimental Translocation of Mycobacterium canettii Yields Pulmonary Tuberculosis.

    Science.gov (United States)

    Bouzid, Fériel; Brégeon, Fabienne; Lepidi, Hubert; Donoghue, Helen D; Minnikin, David E; Drancourt, Michel

    2017-12-01

    Mycobacterium canettii , which has a smooth colony morphology, is the tuberculous organism retaining the most genetic traits from the putative last common ancestor of the rough-morphology Mycobacterium tuberculosis complex. To explore whether M. canettii can infect individuals by the oral route, mice were fed phosphate-buffered saline or 10 6 M. canettii mycobacteria and sacrificed over a 28-day experiment. While no M. canettii was detected in negative controls, M. canettii -infected mice yielded granuloma-like lesions for 4/4 lungs at days 14 and 28 postinoculation (p.i.) and positive PCR detection of M. canettii for 5/8 mesenteric lymph nodes at days 1 and 3 p.i. and 5/6 pooled stools collected from day 1 to day 28 p.i. Smooth M. canettii colonies grew from 68% of lungs and 36% of spleens and cervical lymph nodes but fewer than 20% of axillary lymph nodes, livers, brown fat samples, kidneys, or blood samples throughout the 28-day experiment. Ready translocation in mice after digestive tract challenge demonstrates the potential of ingested M. canettii organisms to relocate to distant organs and lungs. The demonstration of this relocation supports the possibility that populations may be infected by environmental M. canettii . Copyright © 2017 American Society for Microbiology.

  14. Studies on the translocation and distribution characteristics of carbon assimilates in blackberry

    International Nuclear Information System (INIS)

    Wang Shuyu; Liu Hongjia

    1990-08-01

    The translocation and distribution characteristics of carbon assimilates were studied with the method of 14 CO 2 feeding. The results indicated that there were different translocation and distribution characteristics of carbon assimilates among the upper, middle and lower leaves in a shoot during annual cycle. Taking away leaves, sun-shading and drought could raise the exporting ratio of carbon assimilates in the feeding leaves and could change the distributing model of the tree. Most of the carbon assimilates were translocated to basic born branch after sun-shading and drought

  15. Translocation of the radioactive caesium via the calyx in persimmon fruit

    International Nuclear Information System (INIS)

    Sekizawa, Haruhito; Sato, Mari; Aihara, Takashi; Murakami, Toshifumi; Hachinohe, Mayumi; Hamamatsu, Shioka

    2016-01-01

    To elucidate pathways of radioactive caesium contamination of persimmon fruit, we investigated translocation via the calyx. We treated calyces of immature and mature fruits (at either stage and both stages) with water containing caesium-137 (1000 Bq/kg) and measured concentrations in the calyx, pericarp, and flesh with a germanium semiconductor detector. All treated fruits had higher levels of radioactive caesium in all tissues than untreated fruits at harvest. The translocated radioactive caesium was retained in the fruit and not retranslocated. These results indicate that radioactive caesium is translocated via the calyx of persimmon at all stages of fruit development and is accumulated in the flesh. (author)

  16. High speed translocation of /sup 86/Rb in the phloem of Tradescantia viridis

    Energy Technology Data Exchange (ETDEWEB)

    Penot, M.

    1976-01-01

    An autoradiographic study of the rooted shoots of Tradescantia viridis showed a high speed translocation of /sup 86/Rb applied to a leaf for short periods of time (5 to 2.5 min). The speed of this translocation (between 840 and 1.440 cm h/sup -1/) speaks for the existence of a very rapid phloem component translocating ions to an active sink, represented here by the growing roots. Pretreatment with cycloheximide (48 h, 50 mg 1/sup -1/) decreases the quantity of this long distance transport but not the velocity.

  17. Experimental observation of G banding verifying X-ray workers' chromosome translocation detected by FISH

    International Nuclear Information System (INIS)

    Sun Yuanming; Li Jin; Wang Qin; Tang Weisheng; Wang Zhiquan

    2002-01-01

    Objective: FISH is the most effective way of detecting chromosome aberration and many factors affect its accuracy. G-banding is used to verify the results of early X-ray workers' chromosome translocation examined by FISH. Methods: The chromosome translocations of early X-ray workers have been analysed by FISH (fluorescence in situ hybridization) and G-banding, yields of translocation treated with statistics. Results: The chromosome aberrations frequencies by tow methods are closely related. Conclusion: FISH is a feasible way to analyse chromosome aberrations of X-ray workers and reconstruct dose

  18. Melanotic Xp11 Translocation Renal Cancer Managed With Radical Nephrectomy and IVC Tumor Thrombectomy

    Directory of Open Access Journals (Sweden)

    Iyad S. Khourdaji

    2017-01-01

    Full Text Available Melanotic Xp11 translocation renal cancer is a rarely observed neoplasm primarily affecting adolescents and young adults. Given the paucity of data describing this malignancy, its natural history and subsequent long-term management are not well understood. We report a case of melanotic Xp11 translocation with tumor thrombus extension managed with radical nephrectomy and inferior vena cava (IVC tumor thrombectomy. To our knowledge, this is the first case report to describe use of conventional tumor thrombectomy techniques in a patient with melanotic Xp11 translocation renal cancer.

  19. Variant Philadelphia translocations with different breakpoints in six chronic myeloid leukemia patients

    Directory of Open Access Journals (Sweden)

    Dilhan Kuru

    2011-09-01

    Full Text Available Objective: The Philadelphia (Ph chromosome, consisting of the t(9;22(q34;q11 translocation, is observed in ~90% of patients with chronic myeloid leukemia (CML. Variant Ph translocations are observed in 5%-10% of CML patients. In variant translocations 3 and possibly more chromosomes are involved. Herein we report 6 CML patients with variant Ph translocations.Materials and Methods: Bone marrow samples were examined using conventional cytogenetic meth ods. Fluorescence in situ hybridization (FISH with whole-chromosome paints and BCR-ABL 1D probes were used to confirm and/or complement the findings, and identify rearrangements beyond the resolution of conventional cytogenetic methods. Results: Variant Ph translocations in the 6 patients were as follows: t(7;22(p22;q11, t(9;22;15(q34;q11;q22, t(15;22(p11;q11, t(1;9;22;3(q24;q34;q11;q21, t(12;22(p13;q11, and t(4;8;9;22(q11;q13;q34;q11.Conclusion: Among the patients, 3 had simple and 3 had complex variant Ph translocations. Two of the presented cases had variant Ph chromosomes not previously described, 1 of which had a new complex Ph translocation involving chromosomes 1, 3, 9, 22, and t(1;9;22;3(q24;q34;q11;q21 apart from a clone with a classical Ph, and the other case had variant Ph translocation with chromosomes 4, 8, 9, and 22, and t(4;8;9;22(q11;q13;q34;q11 full complex translocation. Number of studies reported that some patients with variant Ph translocation were poor responders to imatinib. All of our patients with variant Ph translocations had suboptimal responses to imatinib, denoting a poor prognosis also. Variant Ph translocations may be important as they are associated with prognosis and therapy for CML patients.

  20. Studies on translocation of tritiated assimilates into potatoes and wheat grains

    International Nuclear Information System (INIS)

    Mueller, J.; Diabate, S.; Strack, S.; Raskob, W.

    1993-01-01

    Tritium released in the enviroment may be converted to organically bound tritium (OBT), mainly by photosynthesis in green leaves. Tritiated assimilates can be translocated from leaves to storage organs of crop plants. This should be considered in models calculating the dose due to the ingestion pathway. This paper describes experiments with wheat and potatoes, which have been designed to study the translocation of tritiated assimilates. Additionally, gas exchange measurements have been performed with the leaves of those plants. A model has been developed to estimate the generation of OBT and the translocation of tritiated assimilates into edible plant parts. (orig.) [de

  1. Stem-spermatogonial survival and incidence of reciprocal translocations in the γ-irradiated boar

    International Nuclear Information System (INIS)

    Erickson, B.H.; Martin, P.G.

    1984-01-01

    To assess the effects of γ-radiation on stem-cell survival and incidence of reciprocal translocations, boar testes were irradiated with 100, 200, or 400 rad. Stem-cell survival was markedly affected by 100 rad (51% of control) and reduced to 34% of control by 400 rad. Production of differentiating spermatogonia renewal was incomplete at 12 weeks. Incidence of translocations peaked at 200 rad and the number occurring at 100 and 400 rad was similar. Kinetics of porcine spermatogonial renewal differs considerably from those of the rodent and, relative to the rodent, this may account for the boar's higher sensitivity to stem-cell killing and lower sensitivity to translocation

  2. Active Transcription of rRNA Operons Condenses the Nucleoid in Escherichia coli: Examining the Effect of Transcription on Nucleoid Structure in the Absence of Transertion | Center for Cancer Research

    Science.gov (United States)

    In Escherichia coli the genome must be compacted ∼1,000-fold to be contained in a cellular structure termed the nucleoid. It is proposed that the structure of the nucleoid is determined by a balance of multiple compaction forces and one major expansion force. The latter is mediated by transertion, a coupling of transcription, translation, and translocation of nascent membrane proteins and/or exported proteins.

  3. Detection of reciprocal chromosome translocations as an indicator of organism exposure to ionizing radiation by FISH-WCP method

    International Nuclear Information System (INIS)

    Holeckova, B.; Sivikova, K.; Dianovsky, J.; Piesova, E.; Lakatosova, M.

    2006-01-01

    Chromosome translocations are considered to be the gold standard for assessing ionizing radiation exposure. Because translocations are inherently more stable through cell division than dicentrics, translocations have become the aberration of choice for evaluating many types of exposure. Fluorescence in situ hybridization with whole chromosome painting probes (FISH-WCP) has been shown to be a rapid method of detecting chromosomal rearrangements, and appears to be especially useful for analysis of induced translocations. The present paper shortly describes FISH-WCP method for detection of reciprocal translocations as indicators of exposure to ionizing radiation. (authors)

  4. Annual Surveillance Summary: Escherichia coli (E. coli) Infections in the Military Health System (MHS), 2015

    Science.gov (United States)

    2017-03-01

    Annual Surveillance Summary: Escherichia coli ( E . coli ) Infections in the Military Health System (MHS...or position of the Department of the Navy, Department of Defense, nor the U.S. Government. i i E . coli in the MHS: Annual Summary 2015 Prepared...March 2017 EpiData Center Department NMCPHC-EDC-TR-187-2017 ii ii E . coli in the MHS: Annual Summary 2015 Prepared March 2017 EpiData

  5. Chromosomal features of Escherichia coli serotype O2:K2, an avian pathogenic E. coli.

    Science.gov (United States)

    Jørgensen, Steffen L; Kudirkiene, Egle; Li, Lili; Christensen, Jens P; Olsen, John E; Nolan, Lisa; Olsen, Rikke H

    2017-01-01

    Escherichia coli causing infection outside the gastrointestinal system are referred to as extra-intestinal pathogenic E. coli. Avian pathogenic E. coli is a subgroup of extra-intestinal pathogenic E. coli and infections due to avian pathogenic E. coli have major impact on poultry production economy and welfare worldwide. An almost defining characteristic of avian pathogenic E. coli is the carriage of plasmids, which may encode virulence factors and antibiotic resistance determinates. For the same reason, plasmids of avian pathogenic E. coli have been intensively studied. However, genes encoded by the chromosome may also be important for disease manifestation and antimicrobial resistance. For the E. coli strain APEC_O2 the plasmids have been sequenced and analyzed in several studies, and E. coli APEC_O2 may therefore serve as a reference strain in future studies. Here we describe the chromosomal features of E. coli APEC_O2. E. coli APEC_O2 is a sequence type ST135, has a chromosome of 4,908,820 bp (plasmid removed), comprising 4672 protein-coding genes, 110 RNA genes, and 156 pseudogenes, with an average G + C content of 50.69%. We identified 82 insertion sequences as well as 4672 protein coding sequences, 12 predicated genomic islands, three prophage-related sequences, and two clustered regularly interspaced short palindromic repeats regions on the chromosome, suggesting the possible occurrence of horizontal gene transfer in this strain. The wildtype strain of E. coli APEC_O2 is resistant towards multiple antimicrobials, however, no (complete) antibiotic resistance genes were present on the chromosome, but a number of genes associated with extra-intestinal disease were identified. Together, the information provided here on E. coli APEC_O2 will assist in future studies of avian pathogenic E. coli strains, in particular regarding strain of E. coli APEC_O2, and aid in the general understanding of the pathogenesis of avian pathogenic E. coli .

  6. The chromosomal risk in sperm from heterozygous Robertsonian translocation carriers is related to the sperm count and the translocation type.

    Science.gov (United States)

    Ferfouri, Fatma; Selva, Jacqueline; Boitrelle, Florence; Gomes, Denise Molina; Torre, Antoine; Albert, Martine; Bailly, Marc; Clement, Patrice; Vialard, François

    2011-12-01

    To study the chromosomal risk in sperm from Robertsonian translocation (RobT) carriers as a function of the sperm count and translocation type. Prospective study. Departments of reproductive biology, cytogenetics, gynecology, and obstetrics. A total of 29 RobT patients (8 normozoospermic and 21 oligozoospermic) and 20 46,XY patients (10 normozoospermic and 10 oligozoospermic). Sperm fluorescence in situ hybridization with probes for translocation malsegregation and chromosome 13, 18, 21, X, and Y probes for studying the interchromosomal effect (ICE). Translocation malsegregation and ICE aneuploidy rates. In RobT carriers, the sperm translocation malsegregation rate was significantly lower in normozoospermic patients (9.7%) than in oligozoospermic patients (18.0%). Considering only oligozoospermic patients, sperm malsegregation rates were significantly lower for rob(14;21) than for rob(13;14) (11.4% vs. 18.9%). In turn, the rates were significantly lower for rob(13;14) than for rare RobTs (18.9% vs. 25.3%). In sperm from normozoospermic RobT, an ICE was suggested by higher chromosome 13 and 21 aneuploidy rates than in control sperm. Conversely, chromosome 13 and 21 sperm aneuploidy rates were lower in oligozoospermic RobT patients than in oligozoospermic 46,XY patients, but higher than in control subjects. Both translocation type and sperm count influence the RobT malsegregation risk. Of the chromosomes analyzed (13, 18, 21, X, and Y), only chromosomes 13 and 21 were found to be associated with an ICE. Relative to the RobT effect, idiopathic alterations in spermatogenesis in 46,XY patients appear to be more harmful for meiosis. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  7. SIRT1 interacts with and protects glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from nuclear translocation: Implications for cell survival after irradiation

    International Nuclear Information System (INIS)

    Joo, Hyun-Yoo; Woo, Seon Rang; Shen, Yan-Nan; Yun, Mi Yong; Shin, Hyun-Jin; Park, Eun-Ran; Kim, Su-Hyeon; Park, Jeong-Eun; Ju, Yeun-Jin; Hong, Sung Hee; Hwang, Sang-Gu; Cho, Myung-Haing; Kim, Joon; Lee, Kee-Ho

    2012-01-01

    Highlights: ► SIRT1 serves to retain GAPDH in the cytosol, preventing GAPDH nuclear translocation. ► When SIRT1 is depleted, GAPDH translocation occurs even in the absence of stress. ► Upon irradiation, SIRT1 interacts with GAPDH. ► SIRT1 prevents irradiation-induced nuclear translocation of GAPDH. ► SIRT1 presence rather than activity is essential for inhibiting GAPDH translocation. -- Abstract: Upon apoptotic stimulation, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a cytosolic enzyme normally active in glycolysis, translocates into the nucleus and activates an apoptotic cascade therein. In the present work, we show that SIRT1 prevents nuclear translocation of GAPDH via interaction with GAPDH. SIRT1 depletion triggered nuclear translocation of cytosolic GAPDH even in the absence of apoptotic stress. Such translocation was not, however, observed when SIRT1 enzymatic activity was inhibited, indicating that SIRT1 protein per se, rather than the deacetylase activity of the protein, is required to inhibit GAPDH translocation. Upon irradiation, SIRT1 prevented irradiation-induced nuclear translocation of GAPDH, accompanied by interaction of SIRT1 and GAPDH. Thus, SIRT1 functions to retain GAPDH in the cytosol, protecting the enzyme from nuclear translocation via interaction with these two proteins. This serves as a mechanism whereby SIRT1 regulates cell survival upon induction of apoptotic stress by means that include irradiation.

  8. Hemolytic porcine intestinal Escherichia coli without virulence-associated genes typical of intestinal pathogenic E. coli.

    Science.gov (United States)

    Schierack, Peter; Weinreich, Joerg; Ewers, Christa; Tachu, Babila; Nicholson, Bryon; Barth, Stefanie

    2011-12-01

    Testing 1,666 fecal or intestinal samples from healthy and diarrheic pigs, we obtained hemolytic Escherichia coli isolates from 593 samples. Focusing on hemolytic E. coli isolates without virulence-associated genes (VAGs) typical for enteropathogens, we found that such isolates carried a broad variety of VAGs typical for extraintestinal pathogenic E. coli.

  9. A case of posttraumatic splenic translocation into the thorax; Przypadek pourazowego przemieszczenia sledziony do klatki piersiowej

    Energy Technology Data Exchange (ETDEWEB)

    Sosnowski, P.; Sikorski, L.; Ziemianski, A. [Akademia Medyczna, Poznan (Poland)

    1993-12-31

    A case of the left diaphragmatic hernia due to blunt thoracic and abdominal trauma is presented. Characteristic radiological signs of splenic translocation into the thorax contributed to quick diagnosis and immediate surgical intervention. (author). 5 refs, 2 figs.

  10. A Brownian motor mechanism of translocation and strand separation by hepatitis C virus helicase.

    Science.gov (United States)

    Levin, Mikhail K; Gurjar, Madhura; Patel, Smita S

    2005-05-01

    Helicases translocate along their nucleic acid substrates using the energy of ATP hydrolysis and by changing conformations of their nucleic acid-binding sites. Our goal is to characterize the conformational changes of hepatitis C virus (HCV) helicase at different stages of ATPase cycle and to determine how they lead to translocation. We have reported that ATP binding reduces HCV helicase affinity for nucleic acid. Now we identify the stage of the ATPase cycle responsible for translocation and unwinding. We show that a rapid directional movement occurs upon helicase binding to DNA in the absence of ATP, resulting in opening of several base pairs. We propose that HCV helicase translocates as a Brownian motor with a simple two-stroke cycle. The directional movement step is fueled by single-stranded DNA binding energy while ATP binding allows for a brief period of random movement that prepares the helicase for the next cycle.

  11. Variants forms of Philadelphia translocation in two patients with chronic myeloid leukemia

    International Nuclear Information System (INIS)

    Valent, A.; Zamecnikova, A.; Krizan, P.; Karlic, H.; Nowotny, H.

    1996-01-01

    During a 4-year period (December 1990-December 1994), among other diagnoses hundred cases of chronic myeloid leukemia (CML) were analyzed in our departments. We focused our attention on two cases with a variant form of Philadelphia translocation. Cytogenetic and molecular genetic studies were performed to resolve the status of BCR and ABL in the bone marrow or peripheral blood cells of the two CML patients with complex translocations involving chromosomes, 3, 9, 22 and 9, 12, 22 respectively. In the first case the presence of Ph chromosome was detected cytogenetically, BCR-ABL translocation was detected by Southern hybridization. In the second phase, only the PCR method showed BCR-ABL rearrangement. The second case, with a random variant form of Ph translocation, could be detected using different methods of clinical molecular genetics. (author)

  12. Complex Variant t(9;22 Chromosome Translocations in Five Cases of Chronic Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Ana Valencia

    2009-01-01

    Full Text Available The Philadelphia (Ph1 chromosome arising from the reciprocal t(9;22 translocation is found in more than 90% of chronic myeloid leukemia (CML patients and results in the formation of the chimeric fusion gene BCR-ABL. However, a small proportion of patients with CML have simple or complex variants of this translocation, involving various breakpoints in addition to 9q34 and 22q11. We report five CML cases carrying variant Ph translocations involving both chromosomes 9 and 22 as well as chromosomes 3, 5, 7, 8, or 10. G-banding showed a reciprocal three-way translocation involving 3q21, 5q31, 7q32, 8q24, and 10q22 bands. BCR-ABL fusion signal on der(22 was found in all of the cases by FISH.

  13. High positive end-expiratory pressure levels promote bacterial translocation in experimental pneumonia

    NARCIS (Netherlands)

    Lachmann, Robert A.; van Kaam, Anton H.; Haitsma, Jack J.; Lachmann, Burkhard

    2007-01-01

    A previous study in piglets with experimental pneumonia showed that reducing atelectasis by means of open lung ventilation attenuated bacterial translocation compared to conventional ventilation settings. This study examined the effect of open lung ventilation with higher than necessary positive

  14. Characterization of uptake and translocation of radioactive herbicides in a parasitic-host system

    International Nuclear Information System (INIS)

    Diaz S, Jorge; Lopez G, Francisca; Garcia T, Luis

    1999-01-01

    Uptake and translocation of [14C]-propyzamide applied to the sunflower seed by coating or soaking, of [14C]-imazapyr and [14C]-glyphosate both applied at post emergence, were studied in sunflower (Helianthus annuus L.) parasitising or not by nodding broom rape (Orobanche cumana Wallr.). Sunflower seed absorbed 9.8 and 3.4% of [14C]-propyzamide applied by coating or soaking, respectively, and less than 1% was translocated to the nodding broom rape. In sunflower plants infested and not infested with nodding broom rape, nearly 90% of [14C]-imazapyr was absorbed and 26% was translocated to the parasitic weed. Uptake of [14C]-glyphosate was similar (50%) for infested or not infested sunflower plants and only the 6% was translocated to the nodding broom rape

  15. Transport of radiocesium in mycelium and its translocation to fruitbodies of a saprophytic macromycete

    Energy Technology Data Exchange (ETDEWEB)

    Bazala, Michal A.; Golda, Katarzyna [Isotope Laboratory, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw (Poland); Bystrzejewska-Piotrowska, Grazyna [Isotope Laboratory, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw (Poland)], E-mail: byst@biol.uw.edu.pl

    2008-07-15

    We present a new protocol to study fluxes of radionuclides and other xenobiotics in saprophytic fungi. This simple method has successfully been used to evaluate transport of radiocesium in hyphae of Pleurotus eryngii and its translocation to fruitbodies.

  16. Nectar reabsorption and sugar translocation in male and female flowers of Cucurbita pepo

    International Nuclear Information System (INIS)

    Stpiczynska, M.; Nepi, M.

    2005-01-01

    Full text: The production and secretion of nectar has an energy cost that can be a substantial part of the energy economy of the plant. Plants may therefore recover part of the energy allocated to nectar secretion by reabsorbing nectar not collected by pollinators. This energy-saving strategy has been demonstrated by several authors by different methods. Here we demonstrate nectar reabsorption and sugar translocation in Cucurbita pepo by means of microautoradiography. Our results confirm that the dynamics of nectar reabsorption is different in male and female flowers. Differences in the dynamics of nectar reabsorption and sugar translocation were also found in pollinated and unpollinated female flowers. Pollinated female flowers reabsorbed sugar very quickly and translocated it to developing fruits in which ovules were the main sugar sink. Sugar translocation was slower and ovules did not label in unpollinated female flowers. (author)

  17. Robertsonian translocation 13/14 associated with rRNA genes ...

    African Journals Online (AJOL)

    Robertsonian translocation 13/14 associated with rRNA genes overexpression and intellectual disability. Alexander A. Dolskiy, Natalya A. Lemskaya, Yulia V. Maksimova, Asia R. Shorina, Irina S. Kolesnikova, Dmitry V. Yudkin ...

  18. Study of the frequency of translocations and dicentrics in human spermatozoid using fluorescent in situ hybridization

    International Nuclear Information System (INIS)

    Alvarez, R.; Ponsa, I.; Tusell, L.; Genesca, A.; Miro, R.; Egozcue, J.

    1998-01-01

    Present study has intended to analyze the induction translocations and dicentrics in human sperms irradiated in vitro to the dose 4Gy by means of the use technical in situ hybridization with probes marked fluorescently

  19. High-performance analysis of single interphase cells with custom DNA probes spanning translocation break points

    Science.gov (United States)

    Weier, Heinz-Ulli G.; Munne, S.; Lersch, Robert A.; Marquez, C.; Wu, J.; Pedersen, Roger A.; Fung, Jingly

    1999-06-01

    The chromatin organization of interphase cell nuclei, albeit an object of intense investigation, is only poorly understood. In the past, this has hampered the cytogenetic analysis of tissues derived from specimens where only few cells were actively proliferating or a significant number of metaphase cells could be obtained by induction of growth. Typical examples of such hard to analyze cell systems are solid tumors, germ cells and, to a certain extent, fetal cells such as amniocytes, blastomeres or cytotrophoblasts. Balanced reciprocal translocations that do not disrupt essential genes and thus do not led to disease symptoms exit in less than one percent of the general population. Since the presence of translocations interferes with homologue pairing in meiosis, many of these individuals experience problems in their reproduction, such as reduced fertility, infertility or a history of spontaneous abortions. The majority of translocation carriers enrolled in our in vitro fertilization (IVF) programs carry simple translocations involving only two autosomes. While most translocations are relatively easy to spot in metaphase cells, the majority of cells biopsied from embryos produced by IVF are in interphase and thus unsuitable for analysis by chromosome banding or FISH-painting. We therefore set out to analyze single interphase cells for presence or absence of specific translocations. Our assay, based on fluorescence in situ hybridization (FISH) of breakpoint-spanning DNA probes, detects translocations in interphase by visual microscopic inspection of hybridization domains. Probes are prepared so that they span a breakpoint and cover several hundred kb of DNA adjacent to the breakpoint. On normal chromosomes, such probes label a contiguous stretch of DNA and produce a single hybridization domain per chromosome in interphase cells. The translocation disrupts the hybridization domain and the resulting two fragments appear as physically separated hybridization domains in

  20. Enteroaggregative Escherichia coli in Daycare

    DEFF Research Database (Denmark)

    Hebbelstrup Jensen, Betina; Stensvold, Christen R.; Struve, Carsten

    2016-01-01

    Enteroaggregative Escherichia coli (EAEC) has been associated with persistent diarrhea, reduced growth acceleration, and failure to thrive in children living in developing countries and with childhood diarrhea in general in industrialized countries. The clinical implications of an EAEC carrier...... and answered a questionnaire regarding gastrointestinal symptoms and exposures. Exposures included foreign travel, consumption of antibiotics, and contact with a diseased animal. In the capital area of Denmark, a total of 179 children aged 0-6 years were followed in a cohort study, in the period between 2009...

  1. Carbon 14 absorption and translocation in sugar cane

    International Nuclear Information System (INIS)

    Pimentel, R.M.M.; Sampaio, E.V.S.; Salcedo, I.H.

    1990-01-01

    Plant-cane stools were labelled with sup(14) CO sub(2), in the field, at Goiana-PE, Brazil, when 3, 7 and 11 months old. Each stool was enclosed in a chamber with sup(14) CO sub(2) for 90 minutes. The sub(14) C photosynthetic were measured in leaves, stalks, roots and soil 24 hours after labelling. Roots were divided into alive and dead and soil into rhizosphere and outer soil. At the end of the labelling period at 3, 7 and 11 months, 2, 19 and 1% of the initial sup(14) CO sub(2) were recovered in the plant and the soil. The low recovery of sub(14) C at 3 months could be attribute to losses by respiration and lack of sampling of the top growing point. The low CO sub(2) fixation and losses at first sampling in the 7 month old labelling were attributed to low light intensity during the day of labelling. Most of the recovered sub(14) C (>80%) was founded in the leaves but all plant parts received labelled photosynthetic. At 3 months, most of the sub(14) C translocated from the leaves went to the living roots (83%); at 7 and 11 months it went to the stalks (69 and 66%). While the roots received less than 2%. Root masses did not vary consistently along the plant cycle and dead root masses were always less than 10% of the total root mass. Radioactivity in the dead roots was always very low. These results suggest that the root system have a low turnover rate after 3 months old. (author)

  2. Chromosomal translocation in a mongoloid male child and his normal mother

    Directory of Open Access Journals (Sweden)

    Willy Beçak

    1963-09-01

    Full Text Available The presence of a translocation 21/13-15 is related in 46 chromosomes, karyotypes of a mongoloid male child (Down's syndrome. The abnormal chromosome was transmitted by the mother of the patient. The possible deficiency of translocated chromosome 21 and the possible origin of the anomaly in the family was discussed and the presence of a markedly large Y chromosome in the karyotypes of the patient as in those of his father was also noted.

  3. Primary vitreoretinal dysplasia resembling Norrie's disease in a female: association with X autosome chromosomal translocation.

    OpenAIRE

    Ohba, N.; Yamashita, T.

    1986-01-01

    A female infant with the typical clinical and histopathological features of vitreoretinal dysplasia is described. She had an apparently balanced reciprocal chromosomal translocation 46XX,t(X;10) with the X chromosome breakpoint being on the short arm. Since the parents' karyotypes were normal, it is most plausible that a de novo chromosomal translocation disrupted the vitreoretinal dysplasia gene itself. The severe clinical symptoms of this heterozygous female patient were explained by non-ra...

  4. Short-Term Space-Use Patterns of Translocated Mojave Desert Tortoise in Southern California.

    Directory of Open Access Journals (Sweden)

    Matthew L Farnsworth

    Full Text Available Increasingly, renewable energy comprises a larger share of global energy production. Across the western United States, public lands are being developed to support renewable energy production. Where there are conflicts with threatened or endangered species, translocation can be used in an attempt to mitigate negative effects. For the threatened Mojave desert tortoise (Gopherus agassizii, we sought to compare habitat- and space-use patterns between short-distance translocated, resident, and control groups. We tested for differences in home range size based on utilization distributions and used linear mixed-effects models to compare space-use intensity, while controlling for demographic and environmental variables. In addition, we examined mean movement distances as well as home range overlap between years and for male and female tortoises in each study group. During the first active season post-translocation, home range size was greater and space-use intensity was lower for translocated tortoises than resident and control groups. These patterns were not present in the second season. In both years, there was no difference in home range size or space-use intensity between control and resident groups. Translocation typically resulted in one active season of questing followed by a second active season characterized by space-use patterns that were indistinguishable from control tortoises. Across both years, the number of times a tortoise was found in a burrow was positively related to greater space-use intensity. Minimizing the time required for translocated tortoises to exhibit patterns similar to non-translocated individuals may have strong implications for conservation by reducing exposure to adverse environmental conditions and predation. With ongoing development, our results can be used to guide future efforts aimed at understanding how translocation strategies influence patterns of animal space use.

  5. Effects of age and sex ratios on offspring recruitment rates in translocated black rhinoceros.

    Science.gov (United States)

    Gedir, Jay V; Law, Peter R; du Preez, Pierre; Linklater, Wayne L

    2018-06-01

    Success of animal translocations depends on improving postrelease demographic rates toward establishment and subsequent growth of released populations. Short-term metrics for evaluating translocation success and its drivers, like postrelease survival and fecundity, are unlikely to represent longer-term outcomes. We used information theory to investigate 25 years of data on black rhinoceros (Diceros bicornis) translocations. We used the offspring recruitment rate (ORR) of translocated females-a metric integrating survival, fecundity, and offspring recruitment at sexual maturity-to detect determinants of success. Our unambiguously best model (AICω = 0.986) predicted that ORR increases with female age at release as a function of lower postrelease adult rhinoceros sex ratio (males:females). Delay of first postrelease reproduction and failure of some females to recruit any calves to sexual maturity most influenced the pattern of ORRs, and the leading causes of recruitment failure were postrelease female death (23% of all females) and failure to calve (24% of surviving females). We recommend translocating older females (≥6 years old) because they do not exhibit the reproductive delay and low ORRs of juveniles (recruitment failure of juveniles and young adults (4-5.9 years old). Where translocation of juveniles is necessary, they should be released into female-biased populations, where they have higher ORRs. Our study offers the unique advantage of a long-term analysis across a large number of replicate populations-a science-by-management experiment as a proxy for a manipulative experiment, and a rare opportunity, particularly for a large, critically endangered taxon such as the black rhinoceros. Our findings differ from previous recommendations, reinforce the importance of long-term data sets and comprehensive metrics of translocation success, and suggest attention be shifted from ecological to social constraints on population growth and species recovery, particularly

  6. Increased frequency of chromosome translocations in airline pilots with long-term flying experience.

    Science.gov (United States)

    Yong, L C; Sigurdson, A J; Ward, E M; Waters, M A; Whelan, E A; Petersen, M R; Bhatti, P; Ramsey, M J; Ron, E; Tucker, J D

    2009-01-01

    Chromosome translocations are an established biomarker of cumulative exposure to external ionising radiation. Airline pilots are exposed to cosmic ionising radiation, but few flight crew studies have examined translocations in relation to flight experience. We determined the frequency of translocations in the peripheral blood lymphocytes of 83 airline pilots and 50 comparison subjects (mean age 47 and 46 years, respectively). Translocations were scored in an average of 1039 cell equivalents (CE) per subject using fluorescence in situ hybridisation (FISH) whole chromosome painting and expressed per 100 CE. Negative binomial regression models were used to assess the relationship between translocation frequency and exposure status and flight years, adjusting for age, diagnostic x ray procedures, and military flying. There was no significant difference in the adjusted mean translocation frequency of pilots and comparison subjects (0.37 (SE 0.04) vs 0.38 (SE 0.06) translocations/100 CE, respectively). However, among pilots, the adjusted translocation frequency was significantly associated with flight years (p = 0.01) with rate ratios of 1.06 (95% CI 1.01 to 1.11) and 1.81 (95% CI 1.16 to 2.82) for a 1- and 10-year incremental increase in flight years, respectively. The adjusted rate ratio for pilots in the highest compared to the lowest quartile of flight years was 2.59 (95% CI 1.26 to 5.33). Our data suggests that pilots with long-term flying experience may be exposed to biologically significant doses of ionising radiation. Epidemiological studies with longer follow-up of larger cohorts of pilots with a wide range of radiation exposure levels are needed to clarify the relationship between cosmic radiation exposure and cancer risk.

  7. Preimplantation genetic diagnosis by fluorescence in situ hybridization of reciprocal and Robertsonian translocations.

    Science.gov (United States)

    Chen, Chun-Kai; Wu, Dennis; Yu, Hsing-Tse; Lin, Chieh-Yu; Wang, Mei-Li; Yeh, Hsin-Yi; Huang, Hong-Yuan; Wang, Hsin-Shin; Soong, Yung-Kuei; Lee, Chyi-Long

    2014-03-01

    The presence of reciprocal and Robertsonian chromosomal rearrangement is often related to recurrent miscarriage. Using preimplantation genetic diagnosis, the abortion rate can be decreased. Cases treated at our center were reviewed. A retrospective analysis for either Robertsonian or reciprocal translocations was performed on all completed cycles of preimplantation genetic diagnosis at our center since the first reported case in 2004 until the end of 2010. Day 3 embryo biopsies were carried out, and the biopsied cell was checked by fluorescent in situ hybridization using relevant informative probes. Embryos with a normal or balanced translocation karyotype were transferred on Day 4. Thirty-eight preimplantation genetic diagnosis cycles involving 17 couples were completed. A total of 450 (82.6%) of the total oocytes were MII oocytes, and 158 (60.0%) of the two-pronuclei embryos were biopsied. In 41.4% of the fluorescent in situ hybridization analyses, the results were either normal or balanced. Embryos were transferred back after 21 cycles. Three babies were born from Robertsonian translocation carriers and another two from reciprocal translocation carriers. The miscarriage rate was 0%. Among the reciprocal translocation group, the live delivery rate was 8.3% per ovum pick-up cycle and 18.2% per embryo transfer cycle. Among the Robertsonian translocation group, the live delivery rate was 14.3% per ovum pick-up cycle and 20.0% per embryo transfer cycle. There is a trend whereby the outcome for Robertsonian translocation group carriers is better than that for reciprocal translocation group carriers. Aneuploidy screening may possibly be added in order to improve the outcome, especially for individuals with an advanced maternal age. The emergence of an array-based technology should help improve this type of analysis. Copyright © 2014. Published by Elsevier B.V.

  8. Production and identification of wheat - Agropyron cristatum (1.4P) alien translocation lines.

    Science.gov (United States)

    Liu, Wei-Hua; Luan, Yang; Wang, Jing-Chang; Wang, Xiao-Guang; Su, Jun-Ji; Zhang, Jin-Peng; Yang, Xin-Ming; Gao, Ai-Nong; Li, Li-Hui

    2010-06-01

    The P genome of Agropyron Gaertn., a wild relative of wheat, contains an abundance of desirable genes that can be utilized as genetic resources to improve wheat. In this study, wheat - Aegilops cylindrica Host gametocidal chromosome 2C addition lines were crossed with wheat - Agropyron cristatum (L.) Gaertn. disomic addition line accession II-21 with alien recombinant chromosome (1.4)P. We successfully induced wheat - A. cristatum alien chromosomal translocations for the first time. The frequency of translocation in the progeny was 3.75%, which was detected by molecular markers and genomic in situ hybridization (GISH). The translocation chromosomes were identified by dual-color GISH /fluorescence in situ hybridization (FISH). The P genomic DNA was used as probe to detect the (1.4)P chromosome fragment, and pHvG39, pAs1, or pSc119.2 repeated sequences were used as probes to identify wheat translocated chromosomes. The results showed that six types of translocations were identified in the three wheat - A. cristatum alien translocation lines, including the whole arm or terminal portion of a (1.4)P chromosome. The (1.4)P chromosome fragments were translocated to wheat chromosomes 1B, 2B, 5B, and 3D. The breakpoints were located at the centromeres of 1B and 2B, the pericentric locations of 5BS, and the terminals of 5BL and 3DS. In addition, we obtained 12 addition-deletion lines that contained alien A. cristatum chromosome (1.4)P in wheat background. All of these wheat - A. cristatum alien translocation lines and addition-deletion lines would be valuable for identifying A. cristatum chromosome (1.4)P-related genes and providing genetic resources and new germplasm accessions for the genetic improvement of wheat. The specific molecular markers of A. cristatum (1.4)P chromosome have been developed and used to track the (1.4)P chromatin.

  9. Preclinical Testing of a Translocator Protein Ligand for the Treatment of Amyotrophic Lateral Sclerosis

    Science.gov (United States)

    2017-03-01

    investigated the neuroprotective effect and therapeutic value of a drug : the translocator protein (TSPO) ligand PK11195 (PK), which we found to be...Translocator protein (TSPO) ligand Neuroprotective drugs In vitro models of neurodegeneration Axon preservation Neuromuscular junctions 5 3...pharmacokinetic data of the JNK study were showing that daily gavage (30 mg/kg/day) allowed an efficient delivery of the drugs in the brain and the spinal

  10. Stability of the translocation frequency following whole-body irradiation measured in rhesus monkeys

    Science.gov (United States)

    Lucas, J. N.; Hill, F. S.; Burk, C. E.; Cox, A. B.; Straume, T.

    1996-01-01

    Chromosome translocations are persistent indicators of prior exposure to ionizing radiation and the development of 'chromosome painting' to efficiently detect translocations has resulted in a powerful biological dosimetry tool for radiation dose reconstruction. However, the actual stability of the translocation frequency with time after exposure must be measured before it can be used reliably to obtain doses for individuals exposed years or decades previously. Human chromosome painting probes were used here to measure reciprocal translocation frequencies in cells from two tissues of 8 rhesus monkeys (Macaca mulatta) irradiated almost three decades previously. Six of the monkeys were exposed in 1965 to whole-body (fully penetrating) radiation and two were unexposed controls. The primates were irradiated as juveniles to single doses of 0.56, 1.13, 2.00, or 2.25 Gy. Blood lymphocytes (and skin fibroblasts from one individual) were obtained for cytogenetic analysis in 1993, near the end of the animals' lifespans. Results show identical dose-response relationships 28 y after exposure in vivo and immediately after exposure in vitro. Because chromosome aberrations are induced with identical frequencies in vivo and in vitro, these results demonstrate that the translocation frequencies induced in 1965 have not changed significantly during the almost three decades since exposure. Finally, our emerging biodosimetry data for individual radiation workers are now confirming the utility of reciprocal translocations measured by FISH in radiation dose reconstruction.

  11. Long-distance translocations to create a second millerbird population and reduce extinction risk

    Science.gov (United States)

    Holly Freifeld,; Sheldon Plentovich,; Chris Farmer,; Charles Kohley,; Peter Luscomb,; Work, Thierry M.; Daniel Tsukayama,; George Wallace,; Mark MacDonald,; Sheila Conant,

    2016-01-01

    Translocation is a conservation tool used with increasing frequency to create additional populations of threatened species. In addition to following established general guidelines for translocations, detailed planning to account for unique circumstances and intensive post-release monitoring to document outcomes and guide management are essential components of these projects. Recent translocation of the critically endangered Nihoa millerbird (Acrocephalus familiaris kingi) provides an example of this planning and monitoring. The Nihoa millerbird is a passerine bird endemic to Nihoa Island in the remote Northwestern Hawaiian Islands. The closely related, ecologically similar Laysan millerbird (Acrocephalus familiaris familiaris) went extinct on Laysan Island in the early 20th century when the island was denuded by introduced rabbits. To reduce extinction risk, we translocated 50 adult Nihoa millerbirds more than 1000 km by sea to Laysan, which has recovered substantially in the past century and has ample habitat and a rich prey-base for millerbirds. Following five years of intensive background research and planning, including development of husbandry techniques, fundraising, and regulatory compliance, translocations occurred in 2011 and 2012. Of 11 females in each cohort, 8 (2011 cohort) and 11 (2012 cohort) produced at least one brood of fledglings during their first year on Laysan. At the conclusion of monitoring in September 2014, 37 of the translocated birds were known to survive, and the population was estimated at 164 birds. The reintroduction of millerbirds to Laysan represents a milestone in the island's ongoing restoration.

  12. Connecting the kinetics and energy landscape of tRNA translocation on the ribosome.

    Directory of Open Access Journals (Sweden)

    Paul C Whitford

    Full Text Available Functional rearrangements in biomolecular assemblies result from diffusion across an underlying energy landscape. While bulk kinetic measurements rely on discrete state-like approximations to the energy landscape, single-molecule methods can project the free energy onto specific coordinates. With measures of the diffusion, one may establish a quantitative bridge between state-like kinetic measurements and the continuous energy landscape. We used an all-atom molecular dynamics simulation of the 70S ribosome (2.1 million atoms; 1.3 microseconds to provide this bridge for specific conformational events associated with the process of tRNA translocation. Starting from a pre-translocation configuration, we identified sets of residues that collectively undergo rotary rearrangements implicated in ribosome function. Estimates of the diffusion coefficients along these collective coordinates for translocation were then used to interconvert between experimental rates and measures of the energy landscape. This analysis, in conjunction with previously reported experimental rates of translocation, provides an upper-bound estimate of the free-energy barriers associated with translocation. While this analysis was performed for a particular kinetic scheme of translocation, the quantitative framework is general and may be applied to energetic and kinetic descriptions that include any number of intermediates and transition states.

  13. Genetic analysis of γ-ray induced W-translocation strain on Bombyx nori

    International Nuclear Information System (INIS)

    Onuma, Akio; Murakami, Akio

    1976-01-01

    In the process of analyzing a γ-ray induced mutant of Bombyx nori oo cyte, new type translocation strains of W chromosomes and No.5 chromosomes were detected. The constitution of their translocated chromosomes was assumed to be Z/(W-V) + sup(pe)-V + sup(oc)/v. Owing to such chromosome constitution, it was considered that non-disjunction was induced at meiosis, and Z/(W-V) + sup(pe)/V, Z/(W-V) + sup(pe), V/V were produced besides Z/(W-V) + sup(pe)-V + sup(oc)/V in the female chromosomes (gene) of the next progeny, while V/V and Z/Z, V + sup(oc)/V were produced besides Z/Z, V/V in male. Death of some male eggs in this translocation strain was also observed. No dissociated individual of translocated chromosomes was segregated in the next progeny of the female moth with Z/(W-V) + sup(pe), V/V chromosome constitution and the marker stock male moth, while a few dissociated individuals appeared in the next progeny of Z/(W-V) + sup(pe)-V + sup(oc)/V female moth group. This fact seemed to be resulted from the complicated translocated chromosome constitution of the translocation strain. (Kobatake, H.)

  14. Correlation of leaf damage with uptake and translocation of glyphosate in velvetleaf (Abutilon theophrasti)

    International Nuclear Information System (INIS)

    Feng, P.C.C.; Ryerse, J.S.; Sammons, R.D.

    1998-01-01

    Uptake and translocation of glyphosate in three commercial formulations were examined in velvetleaf, a dicotyledonous weed that is commonly treated with glyphosate. The formulations included Roundup(R) (MON35085), Roundup Ultra, and Touchdown(R) as sold in Canada. A minimal amount of 14C-glyphosate was spiked into a lethal rate of each formulation, and the short-term (3 to 72 h) uptake into the treated leaf and subsequent translocation into the plant were measured. Time-course studies showed very rapid uptake and translocation of glyphosate in the Ultra formulation. In comparison, the uptake and translocation of glyphosate in Touchdown was much slower but continued throughout the 72-h period. Glyphosate in the Roundup formulation showed intermediate uptake and translocation. Tissue necrosis at the application sites of Ultra and Roundup was visible within 24 h after treatment. Examinations using stereo and fluorescence microscopy revealed extensive cell death and tissue disruption. Tissue necrosis from Ultra and Roundup was also observed in blank formulations containing no glyphosate and therefore was likely caused by the surfactants. In contrast, the application sites of Touchdown produced little to no leaf damage. Our results demonstrated a direct correlation between tissue necrosis and rapid rates of glyphosate uptake and translocation. (author)

  15. Effects of an attractive wall on the translocation of polymer under driving

    International Nuclear Information System (INIS)

    Cao Weiping; Wang Chao; Sun Lizhen; Luo Mengbo

    2012-01-01

    The effects of an attractive wall at the trans side on the translocation of an eight-site bond-fluctuation model (BFM) polymer through a pore in a membrane under driving are simulated by the dynamic Monte Carlo method. The attractive wall shows two contrary effects: its excluded volume effect reduces configuration entropy and thus hinders the translocation of the polymer, while its attraction decreases the energy and thus accelerates the translocation. At a critical polymer-wall interaction ε* ≈- 1, we find that the two effects compensate each other and the translocation time τ is roughly independent of the separation distance between the wall and the pore. The value ε* ≈- 1 is roughly equal to the critical adsorption point for the BFM polymer. Moreover, the value of the critical attraction is roughly independent of chain length N and chemical potential difference Δμ. At last, a scaling relation τ ∼ N α is observed for polymer translocation at a high value of NΔμ. Though the translocation time is highly dependent on the polymer-wall interaction and pore-wall separation distance, the exponent α is always about 1.30 ± 0.05 so long as NΔμ is large enough. (paper)

  16. Chromosome translocations in chinese medical X-ray workers analyzed by fluorescence in situ hybridization

    International Nuclear Information System (INIS)

    Sun Yuanming; Li Jin; Wang Qin; Tang Weisheng; Wang Zhiquan

    2002-01-01

    Objective: To study long-term radiation effect in occupational workers exposed to low dose X-rays using the method of fluorescence in situ hybridization (FISH). Method: Chromosome translocations of 25 medical X-ray workers were analyzed by FISH with chromosome No. 4 and No. 7 probes according to PAINT (The Protocol for Aberration Identification and Nomenclature Terminology) system. Results: The frequency of genome translocation in X-ray workers was (13.14 ± 1.23)/1000 cells. The rate of complete and incomplete translocation was 1:1.7. According to the calendar year of entry before/after the year of 1965 as the border, the data showed that the incomplete translocation of the after 1965 group was obviously higher than those of the controls (P < 0.01 and P < 0.05, respectively). Conclusion: The chromosome translocation in early Chinese medical X-ray workers is mainly the incomplete one, the frequency of translocation does not dependent on chromosomal DNA content, and incomplete and complete ones increase along with prolongation of working years in their position

  17. Physiological control of the distribution of translocated amino acids and amides in young soybean plants

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, C D; Gorham, P R

    1959-01-01

    Each of 10 C/sup 14/-labelled amino acids or amides was introduced into young soybean plants through the cut petiole of one primary leaf. The compounds used were asparagine, glutamine, urea, aspartic acid, glutamic acid, glycine, serine, alanine, norleucine, and arginine. The rates of uptake of all the solutions except arginine were in the range 1.0 to 1.5 ..mu..l per minute. After 1 to 5 minutes, the distribution of C/sup 14/ throughout the plants was determined. Each amino acid was translocated as such without conversion to other compounds. From the point of introduction, translocation of each amino acid or amide was mainly downward toward the root; very little was translocated upward. The amount of asparagine or glutamine that was translocated into the primary leaf opposite the cut petiole increased as the leaf aged, while the amount of the other eight compounds decreased as the leaf aged. When asparagine and serine were administered together, serine moved into the young primary leaf while asparagine was excluded. Both excision of the roots and chilling the roots decreased the velocity of downward translocation of aspartic acid indicating that the roots exert a strong demand which favors translocation in a downward direction more than an upward direction in the stem. 17 references, 1 figure, 5 tables.

  18. Uptake and translocation of imidacloprid, clothianidin and flupyradifurone in seed-treated soybeans.

    Science.gov (United States)

    Stamm, Mitchell D; Heng-Moss, Tiffany M; Baxendale, Frederick P; Siegfried, Blair D; Blankenship, Erin E; Nauen, Ralf

    2016-06-01

    Seed treatment insecticides have become a popular management option for early-season insect control. This study investigated the total uptake and translocation of seed-applied [(14) C]imidacloprid, [(14) C]clothianidin and [(14) C]flupyradifurone into different plant parts in three soybean vegetative stages (VC, V1 and V2). The effects of soil moisture stress on insecticide uptake and translocation were also assessed among treatments. We hypothesized that (1) uptake and translocation would be different among the insecticides owing to differences in water solubility, and (2) moisture stress would increase insecticide uptake and translocation. Uptake and translocation did not follow a clear trend in the three vegetative stages. Initially, flupyradifurone uptake was greater than clothianidin uptake in VC soybeans. In V1 soybeans, differences in uptake among the three insecticides were not apparent and unaffected by soil moisture stress. Clothianidin was negatively affected by soil moisture stress in V2 soybeans, while imidacloprid and flupyradifurone were unaffected. Specifically, soil moisture stress had a positive effect on the distribution of flupyradifurone in leaves. This was not observed with the neonicotinoids. This study enhances our understanding of the uptake and distribution of insecticides used as seed treatments in soybean. The uptake and translocation of these insecticides differed in response to soil moisture stress. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  19. Connecting the dots: could microbial translocation explain commonly reported symptoms in HIV disease?

    Science.gov (United States)

    Wilson, Natalie L; Vance, David E; Moneyham, Linda D; Raper, James L; Mugavero, Michael J; Heath, Sonya L; Kempf, Mirjam-Colette

    2014-01-01

    Microbial translocation within the context of HIV disease has been described as one of the contributing causes of inflammation and disease progression in HIV infection. HIV-associated symptoms have been related to inflammatory markers and sCD14, a surrogate marker for microbial translocation, suggesting a plausible link between microbial translocation and symptom burden in HIV disease. Similar pathophysiological responses and symptoms have been reported in inflammatory bowel disease. We provide a comprehensive review of microbial translocation, HIV-associated symptoms, and symptoms connected with inflammation. We identify studies showing a relationship among inflammatory markers, sCD14, and symptoms reported in HIV disease. A conceptual framework and rationale to investigate the link between microbial translocation and symptoms is presented. The impact of inflammation on symptoms supports recommendations to reduce inflammation as part of HIV symptom management. Research in reducing microbial translocation-induced inflammation is limited, but needed, to further promote positive health outcomes among HIV-infected patients. Published by Elsevier Inc.

  20. Changes In water translocation in the vascular tissue of grape during fruit development

    International Nuclear Information System (INIS)

    Zhaosen, X.; Forney, C.F.

    2014-01-01

    The relationship between vascular water translocation in grapes and berry growth was investigated. Berry growth, firmness and turgor were measured, and the structure and function of the vascular bundles for water translocation was observed. During phase I fruit development, the dorsal and central vascular bundles rapidly translocated introduced dye in the pedicle. The speed of dye translocation was highest in the dorsal vascular bundles of phase I fruit with a speed of 0.97cm/h. After phase II, both the distribution of dye and the speed of dye translocation in the fruit vascular tissue decreased, with speeds in the dorsal and central vascular bundles being 0.08 cm/h and 0.72 cm/h, respectively. During phase III, the distribution of dye was still lower than phase I. After phase II, the walls of some xylem vessels were indistinct and broken. After phase III, even though the water translocation efficiency of the xylem decreased, sugar accumulation in the berry as well as osmoregulation increased. (author)

  1. Nuchal translucency thickness and outcome in chromosome translocation diagnosed in the first trimester.

    Science.gov (United States)

    Sepulveda, W; Be, C; Youlton, R; Carstens, E; Reyes, M

    2001-09-01

    In order to determine the significance of nuchal translucency thickness on the subsequent natural history of first-trimester fetuses with a chromosome translocation, seven consecutive cases diagnosed between 11 and 13 weeks of gestation were reviewed. Nuchal translucency measurements were successfully obtained before chorionic villus sampling (CVS) in all cases. Three fetuses had an unbalanced translocation and all were associated with increased nuchal translucency and multiple anomalies at the detailed second-trimester scan. There were no survivors in this group. The remaining four fetuses had a balanced translocation; all had normal nuchal translucency thickness and no structural anomalies were detected in the second trimester. Three of these fetuses were born at > or =35 weeks of gestation and were phenotypically normal. However, an unexpected single fetal demise occurred in a dichorionic twin pregnancy at 28 weeks of gestation. It is concluded that nuchal translucency measurements provide important prognostic information on pregnancy outcome in first-trimester fetuses with a chromosome translocation. In parents with a known balanced translocation, the detection of increased nuchal translucency at 11-14 weeks of gestation is associated with unbalanced translocations, structural anomalies and poor pregnancy outcome. Copyright 2001 John Wiley & Sons, Ltd.

  2. Movements and survival of black-footed ferrets associated with an experimental translocation in South Dakota

    Science.gov (United States)

    Biggins, D.E.; Godbey, J.L.; Horton, B.M.; Livieri, T.M.

    2011-01-01

    Black-footed ferrets (Mustela nigripes) apparently were extirpated from all native habitats by 1987, and their repatriation requires a combination of captive breeding, reintroductions, and translocations among sites. Improvements in survival rates of released ferrets have resulted from experience in quasi-natural environments during their rearing. Reestablishment of a self-sustaining wild population by 1999 provided the 1st opportunity to initiate new populations by translocating wild-born individuals. Using radiotelemetry, we compared behaviors and survival of 18 translocated wild-born ferrets and 18 pen-experienced captive-born ferrets after their release into a prairie dog colony not occupied previously by ferrets. Translocated wild-born ferrets moved significantly less and had significantly higher short-term survival rates than their captive-born counterparts. Using markrecapture methods, we also assessed potential impacts to the established donor population of removing 37% of its estimated annual production of kits. Annual survival rates for 30 ferret kits remaining at the donor subcomplex were higher than rates for 54 ferret kits at the control subcomplex (unmanipulated) for males (+82%) and females (+32%). Minimum survival of translocated kits did not differ significantly from survival of those at the control subcomplex. Direct translocation of young, wild-born ferrets from site to site appears to be an efficient method to establish new populations. ?? 2011 American Society of Mammalogists.

  3. Investigations on the question of radiation-induced intracellular ion translocations in the liver of rats

    Energy Technology Data Exchange (ETDEWEB)

    Wenning, J

    1975-01-01

    Radiation-induced ion translocations in cellular and/or subcellular units can be detected in the course of the examination of whole organs. The present paper attempts to study this problem in the liver of rats. The size and ion composition of the extracellular space and its subunits (interstice, intravascular space, biliary discharge system) must therefore be known in order to obtain purely cellular electrolyte values. They can be determined with the aid of dilution methods and by applying Donnan's law. For measuring radiation-induced ion translocations in nuclei and mitochondria, they must be isolated in an aqueous phase. Processing in 0.25 mol l/sup -1/ saccharose yields the best results with regard to ion losses, since the vitality of the membranes is largely preserved when using this method. During suspension, some of the nuclei and mitochondria obtained in sacharose solution show considerable ion translocations, depending on the composition of the medium. Irradiation up to 10 kR showed that relatively low doses (100 R) already cause further changes of the electrolyte concentrations of nuclei and mitochondria. In-vivo irradiation of the liver also caused definite potassium-sodium translocations in the nucleus and the mitochondria at doses as low as 100 R. These intracellular electrolyte translocations cannot be detected in examinations of the whole organ. All in all, it is shown that intracellular ion translocations can be found at relatively low radiation doses already. The present paper discusses the possible methods by which they can be detected.

  4. Breeding few-seed/seedless watermelon via chromosome reciprocal translocation induced by gamma-ray

    International Nuclear Information System (INIS)

    Ming, W.; Xingping, Z.; Xian, Z.; Kechi, N.; Shuai, Z.; Juenlian, Z.

    1988-01-01

    The development of autotriploid watermelon was a great advance in the field of watermelon breeding. However, some disadvantages still existed with this type of seedless watermelon. Partial sterility may be induced in diploid watermelon via chromosome reciprocal translocation. We used gamma-rays to irradiate the seeds of homozygous translocation strains with one translocation ring composed of 4 chromosomes (symbol (4) ). Watermelon strains were 'Asahi Yamato', 'Mioyaka', and 'Fumin' saent to us by H. Kihara in 1977. In order to further induce multiple reciprocal translocations for developing new few-seed/seedless watermelon strains, the seeds of the above 3 strains were sown for further selfing in 1978. The seeds of each selfed fruit were grown as a single plant line in 1979 for evaluation of their characters. In addition, some crosses between common diploid watermelon cultivars and translocations were carried out to test the seed setting rate of the heterozygous translocation strains. Some of the crosses were 'Sugar Baby' x 'Asahi Yamato AT-1' and 'Akakotama' x Asahi Yamato AT-2'. The plump seed setting rate of the F1 of these crosses were ca. 50%

  5. A kinetic Monte Carlo approach to investigate antibiotic translocation through bacterial porins

    International Nuclear Information System (INIS)

    Ceccarelli, Matteo; Ruggerone, Paolo; Vargiu, Attilio V

    2012-01-01

    Many relevant biological processes take place on time scales not reachable by standard all-atom computer simulations. The translocation of antibiotics through non-specific bacterial porins is an example. Microscopic effects compete to determine penetration routes and, consequently, free energy barriers to be overcome. Since bacteria can develop resistance to treatment also by reducing their antibiotic permeability, to understand the microscopic aspects of antibiotic translocation is an important step to rationalize drug design. Here, to investigate the translocation we propose a complete numerical model that combines the diffusion-controlled rate theory and a kinetic Monte Carlo scheme based on both experimental data and microscopically well-founded all-atom simulations. Within our model, an antibiotic translocating through an hour-glass-shaped channel can be described as a molecule moving on a potential of mean force featuring several affinity sites and a high central barrier. The implications of our results for the characterization of antibiotic translocation at in vivo concentrations are discussed. The presence of an affinity site close to the mouth of the channel seems to favor the translocation of antibiotics, the affinity site acting as a particle reservoir. Possible connections between results and the appearance of mutations in clinical strains are also outlined. (paper)

  6. Translocation of Candida albicans is related to the blood flow of individual intestinal villi.

    Science.gov (United States)

    Gianotti, L; Alexander, J W; Fukushima, R; Childress, C P

    1993-08-01

    Splanchnic ischemia is associated with increased bacterial translocation, but previous observations showed that translocation of Candida albicans did not occur uniformly among individual intestinal villi. This study was performed to investigate the relationship between the degree of Candida translocation and the microcirculation of individual villi. Thiry-Vella intestinal loops were created in eight guinea pigs. One week later, the distal aorta and right carotid artery were cannulated, and systemic blood pressure was recorded throughout the entire experiment. C. albicans (1 x 10(10)) was introduced into the Thiry-Vella loop, and the animals underwent a 40% full-thickness burn. Systolic hypotension was observed in the first 75 minutes postburn; then the systemic blood pressure returned to a normal range. Four hours after burn, 8 x 10(7) microspheres (10 microns) were injected into the aorta. The animals were sacrificed, and the Thiry-Vella loops were harvested and processed for light microscopy. At the microscopic level, within each villus, both the number of beads trapped in the arterioles and the number of Candida translocated into the enterocytes were counted. An inverse linear correlation between number of beads and number of translocated yeast per individual villus was found (r = -0.78; P flow is an important determinant of the magnitude of microbial translocation, even within individual villi.

  7. Miscoding-induced stalling of substrate translocation on the bacterial ribosome.

    Science.gov (United States)

    Alejo, Jose L; Blanchard, Scott C

    2017-10-10

    Directional transit of the ribosome along the messenger RNA (mRNA) template is a key determinant of the rate and processivity of protein synthesis. Imaging of the multistep translocation mechanism using single-molecule FRET has led to the hypothesis that substrate movements relative to the ribosome resolve through relatively long-lived late intermediates wherein peptidyl-tRNA enters the P site of the small ribosomal subunit via reversible, swivel-like motions of the small subunit head domain within the elongation factor G (GDP)-bound ribosome complex. Consistent with translocation being rate-limited by recognition and productive engagement of peptidyl-tRNA within the P site, we now show that base-pairing mismatches between the peptidyl-tRNA anticodon and the mRNA codon dramatically delay this rate-limiting, intramolecular process. This unexpected relationship between aminoacyl-tRNA decoding and translocation suggests that miscoding antibiotics may impact protein synthesis by impairing the recognition of peptidyl-tRNA in the small subunit P site during EF-G-catalyzed translocation. Strikingly, we show that elongation factor P (EF-P), traditionally known to alleviate ribosome stalling at polyproline motifs, can efficiently rescue translocation defects arising from miscoding. These findings help reveal the nature and origin of the rate-limiting steps in substrate translocation on the bacterial ribosome and indicate that EF-P can aid in resuming translation elongation stalled by miscoding errors.

  8. Recombinase, chromosomal translocations and lymphoid neoplasia: targeting mistakes and repair failures.

    Science.gov (United States)

    Marculescu, Rodrig; Vanura, Katrina; Montpellier, Bertrand; Roulland, Sandrine; Le, Trang; Navarro, Jean-Marc; Jäger, Ulrich; McBlane, Fraser; Nadel, Bertrand

    2006-09-08

    A large number of lymphoid malignancies is characterized by specific chromosomal translocations, which are closely linked to the initial steps of pathogenesis. The hallmark of these translocations is the ectopic activation of a silent proto-oncogene through its relocation at the vicinity of an active regulatory element. Due to the unique feature of lymphoid cells to somatically rearrange and mutate receptor genes, and to the corresponding strong activity of the immune enhancers/promoters at that stage of cell development, B- and T-cell differentiation pathways represent propitious targets for chromosomal translocations and oncogene activation. Recent progress in the understanding of the V(D)J recombination process has allowed a more accurate definition of the translocation mechanisms involved, and has revealed that V(D)J-mediated translocations result both from targeting mistakes of the recombinase, and from illegitimate repair of the V(D)J recombination intermediates. Surprisingly, V(D)J-mediated translocations turn out to be restricted to two specific sub-types of lymphoid malignancies, T-cell acute lymphoblastic leukemias, and a restricted set of mature B-cell Non-Hodgkin's lymphomas.

  9. Use of FISH-translocations analyses for retrospective biological dosimetry: How stable are stable chromosome aberrations?

    International Nuclear Information System (INIS)

    Darroudi, F.

    2000-01-01

    Chromosome aberrations, in particular dicentrics, in peripheral blood lymphocytes are used to estimate the absorbed dose immediately following a radiation accident. However, difficulties for dose estimation arise with old exposures, due to a decline of cells containing unstable dicentric aberrations. The fluorescence in situ hybridisation (FISH) technique employing chromosome specific DNA libraries to 'paint' individual human chromosomes has opened new perspectives for rapid and reliable detection of stable chromosome aberrations such as translocations. The inherent stability of translocations over cell generations has enabled them to be used as a biodosemeter. However, due to the limited life of circulating T-lymphocytes, a level of uncertainty exists on the long-term persistence of stable translocations. The objectives of the present work are to present the current state of knowledge on the stability of translocations detected by FISH. The following aspects have been considered; (1) experience so far of retrospective biological dosimetry in humans following accidental and occupational over-exposure, (2) animal studies using mice and monkeys, (3) the influence of subsequent cell divisions on the yield and persistence of translocations following in vitro irradiation of human lymphocytes, and (4) the needs for further work to standardise and validate the use of FISH as a biological dosemeter, and to investigate the influence of various parameters such as radiation quality, dose rate and the discrimination of sub-types of translocations on persistence. (author)

  10. Peptidoglycan Hydrolases of Escherichia coli

    Science.gov (United States)

    van Heijenoort, Jean

    2011-01-01

    Summary: The review summarizes the abundant information on the 35 identified peptidoglycan (PG) hydrolases of Escherichia coli classified into 12 distinct families, including mainly glycosidases, peptidases, and amidases. An attempt is also made to critically assess their functions in PG maturation, turnover, elongation, septation, and recycling as well as in cell autolysis. There is at least one hydrolytic activity for each bond linking PG components, and most hydrolase genes were identified. Few hydrolases appear to be individually essential. The crystal structures and reaction mechanisms of certain hydrolases having defined functions were investigated. However, our knowledge of the biochemical properties of most hydrolases still remains fragmentary, and that of their cellular functions remains elusive. Owing to redundancy, PG hydrolases far outnumber the enzymes of PG biosynthesis. The presence of the two sets of enzymes acting on the PG bonds raises the question of their functional correlations. It is difficult to understand why E. coli keeps such a large set of PG hydrolases. The subtle differences in substrate specificities between the isoenzymes of each family certainly reflect a variety of as-yet-unidentified physiological functions. Their study will be a far more difficult challenge than that of the steps of the PG biosynthesis pathway. PMID:22126997

  11. Third International E. coli genome meeting

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    Proceedings of the Third E. Coli Genome Meeting are provided. Presentations were divided into sessions entitled (1) Large Scale Sequencing, Sequence Analysis; (2) Databases; (3) Sequence Analysis; (4) Sequence Divergence in E. coli Strains; (5) Repeated Sequences and Regulatory Motifs; (6) Mutations, Rearrangements and Stress Responses; and (7) Origins of New Genes. The document provides a collection of abstracts of oral and poster presentations.

  12. Escherichia Coli Removal from Water Using Electrophotocatalytic ...

    African Journals Online (AJOL)

    Michael Horsfall

    inactivation of bacterial microorganisms in areas with low ... disinfection of water contaminated with fecal indicators such as E. coli ... media, brain heart infusion, sodium chloride, sodium hydroxide ... furnace at temperature 105 and 320°C f0r 60 min. For 2- and .... charge of E. coli logarithmic growth phase might affect the ...

  13. Antimicrobial resistance among commensal Escherichia coli from ...

    African Journals Online (AJOL)

    Commensal bacteria contribute to the distribution and persistence of antimicrobial resistance in the environment. This study monitored antimicrobial resistance in commensal Escherichia coli from the faeces of on-farm and slaughter cattle and beef. A total of 342 (89.5%) E. coli isolates were obtained from 382 samples.

  14. Characterization of Escherichia coli Phylogenetic Groups ...

    African Journals Online (AJOL)

    Background: Escherichia coli strains mainly fall into four phylogenetic groups (A, B1, B2, and D) and that virulent extra‑intestinal strains mainly belong to groups B2 and D. Aim: The aim was to determine the association between phylogenetic groups of E. coli causing extraintestinal infections (ExPEC) regarding the site of ...

  15. Biochemical and serological characterization of Escherichia coli ...

    African Journals Online (AJOL)

    This study was designed to determine the isolation rate, serotypes and biochemical profiles of E. coli from colibacillosis and dead-in-shell embryos in Zaria, Northern-Nigeria. The isolation rate of E. coli from hatcheries studied were 4.67% and 7.50% from farms of Simtu Agricultural Company and National Animal Production ...

  16. PATHOGENIC POTENTIALS OF ESCHERICHIA COLI ISOLATED ...

    African Journals Online (AJOL)

    Electrolyte and haematological parameters in rabbits infected with pathogenic isolates of Escherichia coli from rural water supplies in Rivers State, Nigeria, where monitored. Rabbits were orally infected with suspension containing 3x107 cfu /ml of Escherichia coli to induce diarrhoea, and the electrolyte (sodium, potassium ...

  17. Fosfomycin Resistance in Escherichia coli, Pennsylvania, USA.

    Science.gov (United States)

    Alrowais, Hind; McElheny, Christi L; Spychala, Caressa N; Sastry, Sangeeta; Guo, Qinglan; Butt, Adeel A; Doi, Yohei

    2015-11-01

    Fosfomycin resistance in Escherichia coli is rare in the United States. An extended-spectrum β-lactamase-producing E. coli clinical strain identified in Pennsylvania, USA, showed high-level fosfomycin resistance caused by the fosA3 gene. The IncFII plasmid carrying this gene had a structure similar to those found in China, where fosfomycin resistance is commonly described.

  18. Strategies for Protein Overproduction in Escherichia coli.

    Science.gov (United States)

    Mott, John E.

    1984-01-01

    Examines heterologous expression in Escherichia coli and the role of regulatory sequences which control gene expression at transcription resulting in abundant production of messenger RNA and regulatory sequences in mRNA which promote efficient translation. Also examines the role of E. coli cells in stabilizing mRNA and protein that is…

  19. Escherichia coli survival in waters: Temperature dependence

    Science.gov (United States)

    Knowing the survival rates of water-borne Escherichia coli is important in evaluating microbial contamination and making appropriate management decisions. E. coli survival rates are dependent on temperature, a dependency that is routinely expressed using an analogue of the Q10 mo...

  20. Comparison of 61 Sequenced Escherichia coli Genomes

    DEFF Research Database (Denmark)

    Lukjancenko, Oksana; Wassenaar, T. M.; Ussery, David

    2010-01-01

    Escherichia coli is an important component of the biosphere and is an ideal model for studies of processes involved in bacterial genome evolution. Sixty-one publically available E. coli and Shigella spp. sequenced genomes are compared, using basic methods to produce phylogenetic and proteomics...

  1. Antimicrobial resistance among commensal Escherichia coli from ...

    African Journals Online (AJOL)

    user1

    2012-07-19

    Jul 19, 2012 ... Commensal bacteria contribute to the distribution and persistence of antimicrobial resistance in the environment. This study monitored antimicrobial resistance in commensal Escherichia coli from the faeces of on-farm and slaughter cattle and beef. A total of 342 (89.5%) E. coli isolates were obtained.

  2. Fimbrial adhesins from extraintestinal Escherichia coli

    DEFF Research Database (Denmark)

    Klemm, Per; Hancock, Viktoria; Schembri, Mark A.

    2010-01-01

    Extraintestinal pathogenic Escherichia coli (ExPEC) represent an important subclass of E. coli that cause a wide spectrum of diseases in human and animal hosts. Fimbriae are key virulence factors of ExPEC strains. These long surface located rod-shaped organelles mediate receptor-specific attachment...

  3. lactamase in clinical isolates of Escherichia coli

    African Journals Online (AJOL)

    Jane

    2011-08-22

    Aug 22, 2011 ... The beta lactamase enzyme producing E. coli, resistant to β-lactam antibiotics, created many problems ... Key words: Escherichia coli, β-lactamase enzymes, TEM-type extended spectrum ... difficulties in treatment using antibiotics that are currently ... and chloramphenicol (30 µg) (Mast Diagnostics Ltd., UK).

  4. Entry of a Six-Residue Antimicrobial Peptide Derived from Lactoferricin B into Single Vesicles and Escherichia coli Cells without Damaging their Membranes.

    Science.gov (United States)

    Moniruzzaman, Md; Islam, Md Zahidul; Sharmin, Sabrina; Dohra, Hideo; Yamazaki, Masahito

    2017-08-22

    Lactoferricin B (LfcinB) and shorter versions of this peptide have antimicrobial activity. However, the elementary processes of interactions of these peptides with lipid membranes and bacteria are still not well understood. To elucidate the mechanism of their antimicrobial activity, we investigated the interactions of LfcinB (4-9) (its sequence of RRWQWR) with Escherichia coli cells and giant unilamellar vesicles (GUVs). LfcinB (4-9) and lissamine rhodamine B red-labeled LfcinB (4-9) (Rh-LfcinB (4-9)) did not induce an influx of a membrane-impermeant fluorescent probe, SYTOX green, from the outside of E. coli cells into their cytoplasm, indicating that no damage occurred in their plasma membrane. To examine the activity of LfcinB (4-9) to enter E. coli cytoplasm, we investigated the interaction of Rh-LfcinB (4-9) with single cells of E. coli containing calcein using confocal microscopy. We found that Rh-LfcinB (4-9) entered the cytoplasm without leakage of calcein. Next, we investigated the interactions of Rh-LfcinB (4-9) with single GUVs of dioleoylphosphatidylglycerol (DOPG) and dioleoylphosphatidylcholine (DOPC) mixtures containing a fluorescent probe, Alexa Fluor 647 hydrazide (AF647), using the single GUV method. The results indicate that Rh-LfcinB (4-9) outside the GUV translocated through the GUV membrane and entered its lumen without leakage of AF647. Interaction of Rh-LfcinB (4-9) with DNA increased its fluorescence intensity greatly. Therefore, we can conclude that Rh-LfcinB (4-9) can translocate across lipid membrane regions of the plasma membrane of E. coli cells to enter their cytoplasm without leakage of calcein and its antimicrobial activity is not due to damage of their plasma membranes.

  5. A translocator-specific export signal establishes the translocator-effector secretion hierarchy that is important for type III secretion system function

    Science.gov (United States)

    Tomalka, Amanda G.; Stopford, Charles M.; Lee, Pei-Chung; Rietsch, Arne

    2012-01-01

    Summary Type III secretion systems are used by many Gram-negative pathogens to directly deliver effector proteins into the cytoplasm of host cells. To accomplish this, bacteria secrete translocator proteins that form a pore in the host-cell membrane through which the effector proteins are then introduced into the host cell. Evidence from multiple systems indicates that the pore-forming translocator proteins are exported before effectors, but how this secretion hierarchy is established is unclear. Here we used the P. aeruginosa translocator protein PopD as a model to identify its export signals. The amino-terminal secretion signal and chaperone, PcrH, are required for export under all conditions. Two novel signals in PopD, one proximal to the chaperone-binding site and one at the very C-terminus of the protein, are required for export of PopD before effector proteins. These novel export signals establish the translocator-effector secretion hierarchy, which in turn, is critical for the delivery of effectors into host cells. PMID:23121689

  6. Control of glucokinase translocation in rat hepatocytes by sorbitol and the cytosolic redox state.

    Science.gov (United States)

    Agius, L

    1994-02-15

    In rat hepatocytes cultured in 5 mM glucose, glucokinase activity is present predominantly in a bound state, and during permeabilization of the cells with digitonin in the presence of Mg2+ less than 20% of glucokinase activity is released. However, incubation of hepatocytes with a higher [glucose] [concn. giving half-maximal activation (A50) 15 mM] or with fructose (A50 50 microM) causes translocation of glucokinase from its Mg(2+)-dependent binding site to an alternative site [Agius and Peak (1993) Biochem. J. 296, 785-796]. A comparison of various substrates showed that sorbitol (A50 8 microM) was 6-fold more potent than fructose at causing glucokinase translocation, whereas tagatose was as potent and mannitol was > 10-fold less potent (A50 550 microM). These substrates also stimulate glucose conversion into glycogen with a similar relative potency, suggesting that conversion of glucose into glycogen is dependent on the binding and/or location of glucokinase within the hepatocyte. Ethanol and glycerol inhibited the effects of fructose, sorbitol and glucose on glucokinase translocation, whereas dihydroxy-acetone had a small additive effect at sub-maximal substrate stimulation. The converse effects of glycerol and dihydroxy-acetone suggest a role for the cytosolic NADH/NAD+ redox state in controlling glucokinase translocation. Titrations with three competitive inhibitors of glucokinase did not provide evidence for involvement of glucokinase flux in glucose-induced glucokinase translocation: N-acetylglucosamine inhibited glucose conversion into glycogen, but not glucose-induced glucokinase translocation; glucosamine partially suppressed glucose-induced and fructose-induced glucokinase translocation, at concentrations that caused total inhibition of glucose conversion into glycogen; D-mannoheptulose increased glucokinase release and had an additive effect with glucose. 3,3'-Tetramethylene-glutaric acid (5 mM), an inhibitor of aldose reductase, inhibited glucokinase

  7. Soil amendments effects on radiocesium translocation in forest soils.

    Science.gov (United States)

    Sugiura, Yuki; Ozawa, Hajime; Umemura, Mitsutoshi; Takenaka, Chisato

    2016-12-01

    We conducted an experiment to investigate the potential of phytoremediation by soil amendments in a forest area. To desorb radiocesium ( 137 Cs) from variable charges in the soil, ammonium sulfate (NH 4 + ) and elemental sulfur (S) (which decrease soil pH) were applied to forest soil collected from contaminated area at a rate of 40 and 80 g/m 2 , respectively. A control condition with no soil treatment was also considered. We defined four groups of aboveground conditions: planted with Quercus serrata, planted with Houttuynia cordata, covered with rice straw as litter, and unplanted/uncovered (control). Cultivation was performed in a greenhouse with a regular water supply for four months. Following elemental sulfur treatment, soil pH values were significantly lower than pH values following ammonium sulfate treatment and no treatment. During cultivation, several plant species germinated from natural seeds. No clear differences in aboveground tissue 137 Cs concentrations in planted Q. serrata and H. cordata were observed among the treatments. However, aboveground tissue 137 Cs concentration values in the germinated plants following elemental sulfur treatment were higher than the values following the ammonium sulfate treatment and no treatment. Although biomass values for Q. serrata, H. cordata, and germinated plants following elemental sulfur treatment tended to be low, the total 137 Cs activities in the aboveground tissue of germinated plants were higher than those following ammonium sulfate treatment and no treatment in rice straw and unplanted conditions. Although no significant differences were observed, 137 Cs concentrations in rice straw following ammonium sulfate and elemental sulfur treatments tended to be higher than those in the control case. The results of this study indicate that elemental sulfur lowers the soil pH for a relatively long period and facilitates 137 Cs translocation to newly emerged and settled plants or litter, but affects plant growth in

  8. Bim nuclear translocation and inactivation by viral interferon regulatory factor.

    Directory of Open Access Journals (Sweden)

    Young Bong Choi

    2010-08-01

    Full Text Available Viral replication efficiency is in large part governed by the ability of viruses to counteract pro-apoptotic signals induced by infection of the host cell. Human herpesvirus 8 (HHV-8 uses several strategies to block the host's innate antiviral defenses via interference with interferon and apoptotic signaling. Contributors include the four viral interferon regulatory factors (vIRFs 1-4, which function in dominant negative fashion to block cellular IRF activities in addition to targeting IRF signaling-induced proteins such as p53 and inhibiting other inducers of apoptosis such as TGFbeta receptor-activated Smad transcription factors. Here we identify direct targeting by vIRF-1 of BH3-only pro-apoptotic Bcl-2 family member Bim, a key negative regulator of HHV-8 replication, to effect its inactivation via nuclear translocation. vIRF-1-mediated relocalization of Bim was identified in transfected cells, by both immunofluorescence assay and western analysis of fractionated cell extracts. Also, co-localization of vIRF-1 and Bim was detected in nuclei of lytically infected endothelial cells. In vitro co-precipitation assays using purified vIRF-1 and Bim revealed direct interaction between the proteins, and Bim-binding residues of vIRF-1 were mapped by deletion and point mutagenesis. Generation and experimental utilization of Bim-refractory vIRF-1 variants revealed the importance of vIRF-1:Bim interaction, specifically, in pro-replication and anti-apoptotic activity of vIRF-1. Furthermore, blocking of the interaction with cell-permeable peptide corresponding to the Bim-binding region of vIRF-1 confirmed the relevance of vIRF-1:Bim association to vIRF-1 pro-replication activity. To our knowledge, this is the first report of an IRF protein that interacts with a Bcl-2 family member and of nuclear sequestration of Bim or any other member of the family as a means of inactivation. The data presented reveal a novel mechanism utilized by a virus to control

  9. Frequency and distribution analysis of chromosomal translocations induced by x-ray in human lymphocytes

    International Nuclear Information System (INIS)

    Lopez Hidalgo, Juana Ines

    2000-01-01

    The characteristic of ionizing radiation suggests that induced chromosomal damage in the form of translocations would appear to be randomly distributed. However, the outcome of tests performed in vitro and in vivo (irradiated individuals) are contradictories. The most translocation-related chromosomes, as far as some studies reveal on one hand, appear to be less involved in accordance with others. These data, together with those related to molecular mechanisms involved in translocations production suggest that in G 0 -irradiated cells, the frequency and distribution of this kind of chromosomal rearrangement, does not take place at random. They seem to be affected by in-nucleus chromosome distribution, by each chromosome's DNA length and functional features, by the efficiency of DNA repair mechanisms, and by inter individual differences. The objective of this study was to establish the frequency pattern of each human chromosome involved in radio-induced translocations, as well as to analyze the importance the chromosome length, the activity of DNA polymerase- dependant repair mechanisms, and inter individual differences within the scope of such distribution. To achieve the goals, peripheral blood lymphocytes from healthy donors were irradiated in presence and absence of 2'-3' dideoxithimidine (ddThd), a Β - DNA polymerase inhibitor, which takes part in the base repair mechanism (B E R). The results showed that: The presence of ddThd during the irradiation increase the basal frequency of radioinduced translocations in 60 %. This result suggests that ddThd repair synthesis inhibition can be in itself a valid methodology for radiation-induced bases damage assessment, damage which if not BER-repaired may result in translocation-leading double strand breaks. A statistically significant correlation between translocation frequency and chromosome length, in terms of percentage of genome, has been noticed both in (basal) irradiation and in irradiation with ddThd inhibitor

  10. Driven polymer translocation in good and bad solvent: Effects of hydrodynamics and tension propagation.

    Science.gov (United States)

    Moisio, J E; Piili, J; Linna, R P

    2016-08-01

    We investigate the driven polymer translocation through a nanometer-scale pore in the presence and absence of hydrodynamics both in good and bad solvent. We present our results on tension propagating along the polymer segment on the cis side that is measured for the first time using our method that works also in the presence of hydrodynamics. For simulations we use stochastic rotation dynamics, also called multiparticle collision dynamics. We find that in the good solvent the tension propagates very similarly whether hydrodynamics is included or not. Only the tensed segment is by a constant factor shorter in the presence of hydrodynamics. The shorter tensed segment and the hydrodynamic interactions contribute to a smaller friction for the translocating polymer when hydrodynamics is included, which shows as smaller waiting times and a smaller exponent in the scaling of the translocation time with the polymer length. In the bad solvent hydrodynamics has a minimal effect on polymer translocation, in contrast to the good solvent, where it speeds up translocation. We find that under bad-solvent conditions tension does not spread appreciably along the polymer. Consequently, translocation time does not scale with the polymer length. By measuring the effective friction in a setup where a polymer in free solvent is pulled by a constant force at the end, we find that hydrodynamics does speed up collective polymer motion in the bad solvent even more effectively than in the good solvent. However, hydrodynamics has a negligible effect on the motion of individual monomers within the highly correlated globular conformation on the cis side and hence on the entire driven translocation under bad-solvent conditions.

  11. Preimplantation genetic diagnosis outcomes and meiotic segregation analysis of robertsonian translocation carriers.

    Science.gov (United States)

    Ko, Duck Sung; Cho, Jae Won; Lee, Hyoung-Song; Kim, Jin Yeong; Kang, Inn Soo; Yang, Kwang Moon; Lim, Chun Kyu

    2013-04-01

    To investigate the meiotic segregation patterns of cleavage-stage embryos from robertsonian translocation carriers and aneuploidy of chromosome 18 according to meiotic segregation patterns. Retrospective study. Infertility center and laboratory of reproductive biology and infertility. Sixty-two couples with robertsonian translocation carriers. One blastomere was biopsied from embryos and diagnosed with the use of fluorescence in situ hybridization (FISH). Translocation chromosomes were analyzed with the use of locus-specific and subtelomeric FISH probes. Aneuploidy of chromosome 18 was assessed simultaneously with translocation chromosomes. Preimplantation genetic diagnosis (PGD) outcomes, meiotic segregation patterns of robertsonian translocation, and aneuploidy of chromosome 18 depending on meiotic segregation patterns. Two hundred seventy embryos of 332 transferrable embryos were transferred in 113 cycles, and 27 healthy babies were born. The alternate segregation was significantly higher in male carriers than in female carriers (43.9% vs. 29.9%, respectively), and adjacent segregation was higher in female carriers than in male carriers (44.7% vs. 38.7%, respectively). Aneuploidy of chromosome 18 was significantly increased in 3:0-segregated or chaotic embryos. Forty-seven alternate embryos were excluded from embryo replacement owing to aneuploidy of chromosome 18. In carriers of robertsonian translocation, meiotic segregation showed differences between men and women. Frequent meiotic errors caused by premature predivision or nondisjunction and less stringent checkpoint in women might cause such differences between sexes. Aneuploidy of chromosome 18 might be influenced by meiotic segregation of translocation chromosomes. Factors that cause malsegregation, such as 3:0 or chaotic segregation, seem to play a role in aneuploidy of chromosome 18. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  12. Preferential selection and transfer of euploid noncarrier embryos in preimplantation genetic diagnosis cycles for reciprocal translocations.

    Science.gov (United States)

    Wang, Li; Shen, Jiandong; Cram, David S; Ma, Minyue; Wang, Hui; Zhang, Wenke; Fan, Junmei; Gao, Zhiying; Zhang, Liwen; Li, Zhifeng; Xu, Mengnan; Leigh, Don A; Trounson, Alan O; Liu, Jiayin; Yao, Yuanqing

    2017-10-01

    To develop and validate a new strategy to distinguish between balanced/euploid carrier and noncarrier embryos in preimplantation genetic diagnosis (PGD) cycles for reciprocal translocations and to successfully achieve a live birth after selective transfer of a noncarrier embryo. Retrospective and prospective study. In vitro fertilization (IVF) units. Eleven patients undergoing mate pair sequencing for identification of translocation breakpoints, followed by clinical PGD cycles. Embryo biopsy with 24-chromosome testing to determine carrier status of balanced/euploid embryos. Definition of translocation breakpoints and polymerase chain reaction (PCR) diagnostic primers, correct diagnosis of euploid embryos for carrier status, and a live birth with a normal karyotype after transfer of a noncarrier embryo. In 9 of 11 patients (82%), translocation breakpoints were successfully identified. In four patients with a term PGD pregnancy established with a balanced/euploid embryo of unknown carrier status, the correct carrier status was retrospectively determined, matching with the cytogenetic karyotype of the resulting newborns. In a prospective PGD cycle undertaken by a patient with a 46,XY,t(7;14)(q22;q24.3) translocation, the four balanced/euploid embryos identified comprised three carriers and one noncarrier. Transfer of the noncarrier embryo resulted in birth of a healthy girl who was subsequently confirmed with a normal 46,XX karyotype. The combination of mate pair sequencing and PCR breakpoint analysis of balanced reciprocal translocation derivatives is a novel, reliable, and accurate strategy for distinguishing between carrier and noncarrier balanced/euploid embryos. The method has potential application in clinical PGD cycles for patients with reciprocal translocations or other structural rearrangements. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  13. A comparative study on the uptake and translocation of organochlorines by Phragmites australis

    Energy Technology Data Exchange (ETDEWEB)

    San Miguel, Angélique; Ravanel, Patrick [Laboratoire d’Ecologie Alpine, UMR CNRS n°5553, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 09 (France); Raveton, Muriel, E-mail: muriel.raveton@ujf-grenoble.fr [Laboratoire d’Ecologie Alpine, UMR CNRS n°5553, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 09 (France)

    2013-01-15

    Highlights: ► This study compares uptake/translocation of organochlorine congeners in macrophytes. ► First, root OC uptake was strongly linked with the partitioning/diffusion process. ► With time exposure, bioconcentration increased with OC solubility and volatility. ► Translocation was linked to the combination of water flow and vapor flux transfers. ► The most volatile OCs might be phytovolatilized from foliar surfaces. -- Abstract: Organochlorines (OCs) are persistent chemicals found in various environmental compartments. The differences in the uptake of {sup 14}C-labeled 1,4-dichlorobenzene (DCB), 1,2,4-trichlorobenzene (TCB) and γ-hexachlorocyclohexane (γHCH) by Phragmites australis were investigated under hydroponic conditions. The first step in sorption appears to be correlated with the hydrophobic nature of the compounds, since log-linear correlations were obtained between root concentration factor and partition coefficient (LogK{sub ow}). After 7 days of exposure, plant uptake of DCB, TCB, γHCH was significant with bioconcentration factors reaching 14, 19 and 15, respectively. Afterwards, uptake and translocation were seen to be more complex, with a loss of the simple relationship between uptake and LogK{sub ow}. Linear correlations between the bioconcentration/translocation factors and the physico-chemical properties of OCs were shown, demonstrating that translocation from roots to shoots increases with solubility and volatility of the OCs. This suggests that OC-translocation inside plants might result from the combination of two processes, xylem sap flow and vapor fluxes. {sup 14}C-phytovolatilization was measured and was correlated with the volatility of the compounds; the more volatile OCs being most the likely to be phytovolatilized from foliar surfaces (p = 0.0008). Thus, OC-uptake/translocation appears to proceed at a rate that depends mostly on the OCs hydrophobicity, solubility and volatility.

  14. PAK1 translocates into nucleus in response to prolactin but not to estrogen

    Energy Technology Data Exchange (ETDEWEB)

    Oladimeji, Peter, E-mail: Peter.Oladimeji@rockets.utoledo.edu; Diakonova, Maria, E-mail: mdiakon@utnet.utoledo.edu

    2016-04-22

    Tyrosyl phosphorylation of the p21-activated serine–threonine kinase 1 (PAK1) has an essential role in regulating PAK1 functions in breast cancer cells. We previously demonstrated that PAK1 serves as a common node for estrogen (E2)- and prolactin (PRL)-dependent pathways. We hypothesize herein that intracellular localization of PAK1 is affected by PRL and E2 treatments differently. We demonstrate by immunocytochemical analysis that PAK1 nuclear translocation is ligand-dependent: only PRL but not E2 stimulated PAK1 nuclear translocation. Tyrosyl phosphorylation of PAK1 is essential for this nuclear translocation because phospho-tyrosyl-deficient PAK1 Y3F mutant is retained in the cytoplasm in response to PRL. We confirmed these data by Western blot analysis of subcellular fractions. In 30 min of PRL treatment, only 48% of pTyr-PAK1 is retained in the cytoplasm of PAK1 WT clone while 52% re-distributes into the nucleus and pTyr-PAK1 shuttles back to the cytoplasm by 60 min of PRL treatment. In contrast, PAK1 Y3F is retained in the cytoplasm. E2 treatment causes nuclear translocation of neither PAK1 WT nor PAK1 Y3F. Finally, we show by an in vitro kinase assay that PRL but not E2 stimulates PAK1 kinase activity in the nuclear fraction. Thus, PAK1 nuclear translocation is ligand-dependent: PRL activates PAK1 and induces translocation of activated pTyr-PAK1 into nucleus while E2 activates pTyr-PAK1 only in the cytoplasm. - Highlights: • Prolactin but not estrogen causes translocation of PAK1 into nucleus. • Tyrosyl phosphorylation of PAK1 is required for nuclear localization. • Prolactin but not estrogen stimulates PAK1 kinase activity in nucleus.

  15. Effects of different ligands on epidermal growth factor receptor (EGFR) nuclear translocation

    Energy Technology Data Exchange (ETDEWEB)

    Faria, Jerusa A.Q.A.; Andrade, Carolina de; Goes, Alfredo M. [Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, Belo Horizonte, MG, 31270-901 (Brazil); Rodrigues, Michele A. [Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, Belo Horizonte, MG, 31270-901 (Brazil); Department of General Pathology, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, Belo Horizonte, MG, 31270-901 (Brazil); Gomes, Dawidson A., E-mail: dawidson@ufmg.br [Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, Belo Horizonte, MG, 31270-901 (Brazil)

    2016-09-09

    The epidermal growth factor receptor (EGFR) is activated through binding to specific ligands and generates signals for proliferation, differentiation, migration, and cell survival. Recent data show the role of nuclear EGFR in tumors. Although many EGFR ligands are upregulated in cancers, little is known about their effects on EGFR nuclear translocation. We have compared the effects of six EGFR ligands (EGF, HB-EGF, TGF-α, β-Cellulin, amphiregulin, and epiregulin) on nuclear translocation of EGFR, receptor phosphorylation, migration, and proliferation. Cell fractionation and confocal immunofluorescence detected EGFR in the nucleus after EGF, HB-EGF, TGF-α and β-Cellulin stimulation in a dose-dependent manner. In contrast, amphiregulin and epiregulin did not generate nuclear translocation of EGFR. EGF, HB-EGF, TGF-α and β-Cellulin showed correlations between a higher rate of wound closure and increased phosphorylation of residues in the carboxy-terminus of EGFR, compared to amphiregulin and epiregulin. The data indicate that EGFR is translocated to the nucleus after stimulation with EGF, HB-EGF, TGF-α and β-Cellulin, and that these ligands are related to increased phosphorylation of EGFR tyrosine residues, inducing migration of SkHep-1 cells. - Highlights: • EGF, HB-EGF, TGF-α, β-Cellulin are involved in the EGFR nuclear translocation. • Amphiregulin and epiregulin did not promote nuclear translocation of EGFR. • EGF, HB-EGF, TGF-α and β-Cellulin have a role in SkHep-1 cells migration. • EGFR ligands associated with better prognosis don't stimulate EGFR translocation.

  16. Effects of different ligands on epidermal growth factor receptor (EGFR) nuclear translocation

    International Nuclear Information System (INIS)

    Faria, Jerusa A.Q.A.; Andrade, Carolina de; Goes, Alfredo M.; Rodrigues, Michele A.; Gomes, Dawidson A.

    2016-01-01

    The epidermal growth factor receptor (EGFR) is activated through binding to specific ligands and generates signals for proliferation, differentiation, migration, and cell survival. Recent data show the role of nuclear EGFR in tumors. Although many EGFR ligands are upregulated in cancers, little is known about their effects on EGFR nuclear translocation. We have compared the effects of six EGFR ligands (EGF, HB-EGF, TGF-α, β-Cellulin, amphiregulin, and epiregulin) on nuclear translocation of EGFR, receptor phosphorylation, migration, and proliferation. Cell fractionation and confocal immunofluorescence detected EGFR in the nucleus after EGF, HB-EGF, TGF-α and β-Cellulin stimulation in a dose-dependent manner. In contrast, amphiregulin and epiregulin did not generate nuclear translocation of EGFR. EGF, HB-EGF, TGF-α and β-Cellulin showed correlations between a higher rate of wound closure and increased phosphorylation of residues in the carboxy-terminus of EGFR, compared to amphiregulin and epiregulin. The data indicate that EGFR is translocated to the nucleus after stimulation with EGF, HB-EGF, TGF-α and β-Cellulin, and that these ligands are related to increased phosphorylation of EGFR tyrosine residues, inducing migration of SkHep-1 cells. - Highlights: • EGF, HB-EGF, TGF-α, β-Cellulin are involved in the EGFR nuclear translocation. • Amphiregulin and epiregulin did not promote nuclear translocation of EGFR. • EGF, HB-EGF, TGF-α and β-Cellulin have a role in SkHep-1 cells migration. • EGFR ligands associated with better prognosis don't stimulate EGFR translocation.

  17. Free energy and scalings for polymer translocation through a nanopore: A molecular dynamics simulation study combined with milestoning

    International Nuclear Information System (INIS)

    Xue, Xiang-Gui; Zhao, Li; Lu, Zhong-Yuan; Li, Ze-Sheng

    2012-01-01

    Coarse-grained molecular dynamics simulations combined with milestoning method are used to study the stochastic process of polymer chain translocation though a nanopore. We find that the scalings for polymer translocation process (the chain is initialized with the first monomer in the nanopore) and for polymer escape process (the chain is initialized with the middle monomer in the nanopore) are different. The translocation process is mainly controlled by the entropic barrier, while the polymer escape process is driven by the effective force due to free energy difference. -- Highlights: ► We study polymer translocating through a nanopore by CGMD combined with milestoning. ► We find that the scalings for polymer translocation and for polymer escape are different. ► The translocation process is mainly controlled by the entropic barrier. ► The polymer escape process is driven by the effective force due to free energy difference.

  18. Protein translocation channel of mitochondrial inner membrane and matrix-exposed import motor communicate via two-domain coupling protein.

    Science.gov (United States)

    Banerjee, Rupa; Gladkova, Christina; Mapa, Koyeli; Witte, Gregor; Mokranjac, Dejana

    2015-12-29

    The majority of mitochondrial proteins are targeted to mitochondria by N-terminal presequences and use the TIM23 complex for their translocation across the mitochondrial inner membrane. During import, translocation through the channel in the inner membrane is coupled to the ATP-dependent action of an Hsp70-based import motor at the matrix face. How these two processes are coordinated remained unclear. We show here that the two domain structure of Tim44 plays a central role in this process. The N-terminal domain of Tim44 interacts with the components of the import motor, whereas its C-terminal domain interacts with the translocation channel and is in contact with translocating proteins. Our data suggest that the translocation channel and the import motor of the TIM23 complex communicate through rearrangements of the two domains of Tim44 that are stimulated by translocating proteins.

  19. Effect of bile on growth, peritoneal absorption, and blood clearance of Escherichia coli in E coli peritonitis

    International Nuclear Information System (INIS)

    Andersson, R.; Schalen, C.; Tranberg, K.G.

    1991-01-01

    The effect of intraperitoneal bile on growth, peritoneal absorption, and clearance of Escherichia coli was determined in E coli peritonitis in the rat. In E coli peritonitis, intraperitoneal bacterial counts gradually decreased, whereas they increased (after 2 hours) with subsequent development of bacteremia in E coli plus bile peritonitis. After an intraperitoneal injection of labeled bacteria, blood radioactivity was only initially lower in E coli plus bile peritonitis compared with E coli peritonitis. Clearance from blood was lower in E coli plus bile peritonitis than in E coli peritonitis. Organ localization was similar in E coli peritonitis and E coli plus bile peritonitis with decreased splenic, increased pulmonary, and unchanged hepatic uptakes compared with controls. Impaired peritoneal absorption of bacteria, together with impaired local host defense, is likely to enhance the noxious effect of bile in E coli peritonitis

  20. The impact of conservation-driven translocations on blood parasite prevalence in the Seychelles warbler

    Science.gov (United States)

    Fairfield, Eleanor A.; Hutchings, Kimberly; Gilroy, Danielle L.; Kingma, Sjouke A.; Burke, Terry; Komdeur, Jan; Richardson, David S.

    2016-01-01

    Introduced populations often lose the parasites they carried in their native range, but little is known about which processes may cause parasite loss during host movement. Conservation-driven translocations could provide an opportunity to identify the mechanisms involved. Using 3,888 blood samples collected over 22 years, we investigated parasite prevalence in populations of Seychelles warblers (Acrocephalus sechellensis) after individuals were translocated from Cousin Island to four new islands (Aride, Cousine, Denis and Frégate). Only a single parasite (Haemoproteus nucleocondensus) was detected on Cousin (prevalence = 52%). This parasite persisted on Cousine (prevalence = 41%), but no infection was found in individuals hatched on Aride, Denis or Frégate. It is not known whether the parasite ever arrived on Aride, but it has not been detected there despite 20 years of post-translocation sampling. We confirmed that individuals translocated to Denis and Frégate were infected, with initial prevalence similar to Cousin. Over time, prevalence decreased on Denis and Frégate until the parasite was not found on Denis two years after translocation, and was approaching zero prevalence on Frégate. The loss (Denis) or decline (Frégate) of H. nucleocondensus, despite successful establishment of infected hosts, must be due to factors affecting parasite transmission on these islands. PMID:27405249

  1. PGE2 suppresses intestinal T cell function in thermal injury: a cause of enhanced bacterial translocation.

    Science.gov (United States)

    Choudhry, M A; Fazal, N; Namak, S Y; Haque, F; Ravindranath, T; Sayeed, M M

    2001-09-01

    Increased gut bacterial translocation in burn and trauma patients has been demonstrated in a number of previous studies, however, the mechanism for such an increased gut bacterial translocation in injured patients remains poorly understood. Utilizing a rat model of burn injury, in the present study we examined the role of intestinal immune defense by analyzing the T cell functions. We investigated if intestinal T cells dysfunction contributes to bacterial translocation after burn injury. Also our study determined if burn-mediated alterations in intestinal T cell functions are related to enhanced release of PGE2. Finally, we examined whether or not burn-related alterations in intestinal T cell function are due to inappropriate activation of signaling molecule P59fyn, which is required for T cell activation and proliferation. The results presented here showed an increase in gut bacterial accumulation in mesenteric lymph nodes after thermal injury. This was accompanied by a decrease in the intestinal T cell proliferative responses. Furthermore, the treatments of burn-injured animals with PGE2 synthesis blocker (indomethacin or NS398) prevented both the decrease in intestinal T cell proliferation and enhanced bacterial translocation. Finally, our data suggested that the inhibition of intestinal T cell proliferation could result via PGE2-mediated down-regulation of the T cell activation-signaling molecule P59fyn. These findings support a role of T cell-mediated immune defense against bacterial translocation in burn injury.

  2. A two-step recognition of signal sequences determines the translocation efficiency of proteins.

    Science.gov (United States)

    Belin, D; Bost, S; Vassalli, J D; Strub, K

    1996-02-01

    The cytosolic and secreted, N-glycosylated, forms of plasminogen activator inhibitor-2 (PAI-2) are generated by facultative translocation. To study the molecular events that result in the bi-topological distribution of proteins, we determined in vitro the capacities of several signal sequences to bind the signal recognition particle (SRP) during targeting, and to promote vectorial transport of murine PAI-2 (mPAI-2). Interestingly, the six signal sequences we compared (mPAI-2 and three mutated derivatives thereof, ovalbumin and preprolactin) were found to have the differential activities in the two events. For example, the mPAI-2 signal sequence first binds SRP with moderate efficiency and secondly promotes the vectorial transport of only a fraction of the SRP-bound nascent chains. Our results provide evidence that the translocation efficiency of proteins can be controlled by the recognition of their signal sequences at two steps: during SRP-mediated targeting and during formation of a committed translocation complex. This second recognition may occur at several time points during the insertion/translocation step. In conclusion, signal sequences have a more complex structure than previously anticipated, allowing for multiple and independent interactions with the translocation machinery.

  3. Translocality, Network Structure, and Music Worlds: Underground Metal in the United Kingdom.

    Science.gov (United States)

    Emms, Rachel; Crossley, Nick

    2018-02-01

    Translocal music worlds are often defined as networks of local music worlds. However, their networked character and more especially their network structure is generally assumed rather than concretely mapped and explored. Formal social network analysis (SNA) is beginning to attract interest in music sociology but it has not previously been used to explore a translocal music world. In this paper, drawing upon a survey of the participation of 474 enthusiasts in 148 live music events, spread across 6 localities, we use SNA to explore a significant "slice" of the network structure of the U.K.'s translocal underground heavy metal world. Translocality is generated in a number of ways, we suggest, but one way, the way we focus upon, involves audiences traveling between localities to attend gigs and festivals. Our analysis of this network uncovers a core-periphery structure which, we further find, maps onto locality. Not all live events enjoy equal standing in our music world and some localities are better placed to capture more prestigious events, encouraging inward travel. The identification of such structures, and the inequality they point to, is, we believe, one of several benefits of using SNA to analyze translocal music worlds. © 2018 Canadian Sociological Association/La Société canadienne de sociologie.

  4. Wildlife translocation: the conservation implications of pathogen exposure and genetic heterozygosity

    Science.gov (United States)

    2011-01-01

    Background A key challenge for conservation biologists is to determine the most appropriate demographic and genetic management strategies for wildlife populations threatened by disease. We explored this topic by examining whether genetic background and previous pathogen exposure influenced survival of translocated animals when captive-bred and free-ranging bighorn sheep (Ovis canadensis) were used to re-establish a population that had been extirpated in the San Andres Mountains in New Mexico, USA. Results Although the free-ranging source population had significantly higher multi-locus heterozygosity at 30 microsatellite loci than the captive bred animals, neither source population nor genetic background significantly influenced survival or cause of death. The presence of antibodies to a respiratory virus known to cause pneumonia was associated with increased survival, but there was no correlation between genetic heterozygosity and the presence of antibodies to this virus. Conclusions Although genetic theory predicts otherwise, increased heterozygosity was not associated with increased fitness (survival) among translocated animals. While heterosis or genetic rescue effects may occur in F1 and later generations as the two source populations interbreed, we conclude that previous pathogen exposure was a more important marker than genetic heterozygosity for predicting survival of translocated animals. Every wildlife translocation is an experiment, and whenever possible, translocations should be designed and evaluated to test hypotheses that will further improve our understanding of how pathogen exposure and genetic variability influence fitness. PMID:21284886

  5. Wildlife translocation: the conservation implications of pathogen exposure and genetic heterozygosity

    Directory of Open Access Journals (Sweden)

    Penedo M Cecilia T

    2011-02-01

    Full Text Available Abstract Background A key challenge for conservation biologists is to determine the most appropriate demographic and genetic management strategies for wildlife populations threatened by disease. We explored this topic by examining whether genetic background and previous pathogen exposure influenced survival of translocated animals when captive-bred and free-ranging bighorn sheep (Ovis canadensis were used to re-establish a population that had been extirpated in the San Andres Mountains in New Mexico, USA. Results Although the free-ranging source population had significantly higher multi-locus heterozygosity at 30 microsatellite loci than the captive bred animals, neither source population nor genetic background significantly influenced survival or cause of death. The presence of antibodies to a respiratory virus known to cause pneumonia was associated with increased survival, but there was no correlation between genetic heterozygosity and the presence of antibodies to this virus. Conclusions Although genetic theory predicts otherwise, increased heterozygosity was not associated with increased fitness (survival among translocated animals. While heterosis or genetic rescue effects may occur in F1 and later generations as the two source populations interbreed, we conclude that previous pathogen exposure was a more important marker than genetic heterozygosity for predicting survival of translocated animals. Every wildlife translocation is an experiment, and whenever possible, translocations should be designed and evaluated to test hypotheses that will further improve our understanding of how pathogen exposure and genetic variability influence fitness.

  6. Production of reciprocal translocation lines and genetical analysis of tetravalent behavior in barley

    Energy Technology Data Exchange (ETDEWEB)

    Makino, Tokuhiko

    1988-03-01

    The seeds of a barley cultivar, Chikurinibaraki No.1 and of an early mutant line, Ea 52, derived from it were exposed to the external irradiation of gamma ray and thermal neutrons, and to the internal irradiation with the alpha ray from the nuclear reaction B-10 (n, alpha) Li-7 generated by the thermal neutron irradiation of B-10 imbibed seeds. The reciprocal translocation induced by these irradiation was detected and bred in the pedigrees of irradiated materials by the selection in terms of the partial sterility of seeds. The examination of seed fertility and chromosome pairing at the MI of meiosis of the F/sub 1/ hybrid between the selected lines and the original cultivar was also used. Consequently, 50 homozygous lines of reciprocal translocation were confirmed. The tester lines for translocated chromosomes were established by the cytological examination of the chromosome pairing in the hybrids between each two of the tester lines. The investigation of the inheritance of translocation heterozygotes showed that most of the newly obtained lines differently behaved from the expectation on the genetical basis of reciprocal translocation. (Kako, I.).

  7. Proline accumulation in water-stressed barley leaves in relation to translocation and the nitrogen budget

    International Nuclear Information System (INIS)

    Tully, R.E.; Hanson, A.D.; Nelsen, C.E.

    1979-01-01

    Mobilization of N from leaves of barley (Hordeum vulgare L.) during water stress, and the role of proline as a mobilized species, were examined in plants at the three-leaf stage. The plants responded to water stress by withdrawing about 25% of the total reduced N from the leaf blades via phloem translocation. Most of this N loss was during the first 2 days while translocation of 14 C-photosynthate out of the stressed blade still remained active. Free proline accumulation in the blade was initially slow, and became more rapid during the 2nd day of stress. Although a major free amino acid, proline accounted for only about 5% of the total N(soluble + insoluble) retained in severely stressed blades. When the translocation pathway in water-stressed leaves was interrupted just below the blade by a heat girdle, a cold jacket, or by blade excision, N loss from the blade was prevented and proline began to accumulate rapidly on 1st day of stress. Little free proline accumulated in the blades until after the ability to translocate was lost. Proline was, however, probably not a major species of N translocated during stress, because proline N accumulation in heat-girdled stressed leaves was five times slower than the rate of total N export from intact blades

  8. All-Atom Molecular Dynamics Simulation of Protein Translocation through an α-Hemolysin Nanopore

    KAUST Repository

    Di Marino, Daniele

    2015-08-06

    © 2015 American Chemical Society. Nanopore sensing is attracting the attention of a large and varied scientific community. One of the main issues in nanopore sensing is how to associate the measured current signals to specific features of the molecule under investigation. This is particularly relevant when the translocating molecule is a protein and the pore is sufficiently narrow to necessarily involve unfolding of the translocating protein. Recent experimental results characterized the cotranslocational unfolding of Thioredoxin (Trx) passing through an α-hemolisin pore, providing evidence for the existence of a multistep process. In this study we report the results of all-atom molecular dynamics simulations of the same system. Our data indicate that Trx translocation involves two main barriers. The first one is an unfolding barrier associated with a translocation intermediate where the N-terminal region of Trx is stuck at the pore entrance in a conformation that strongly resembles the native one. After the abrupt unfolding of the N-terminal region, the Trx enters the α-hemolisin vestibule. During this stage, the constriction is occupied not only by the translocating residue but also by a hairpin-like structure forming a tangle in the constriction. The second barrier is associated with the disentangling of this region.

  9. Application of DNA RFLP procedures in interspecific gene transfer: The Lr19 translocation of wheat

    International Nuclear Information System (INIS)

    Prins, R.; Marais, G.F.; Marais, A.S.; Pretorius, Z.A.; Janse, B.J.H.

    1998-01-01

    Twenty-nine lines with deletions in the Lr19 ('Indis') translocated chromosome segment were used to physically map Thinopyrum Restriction Fragment Length Polymorphism (RFLP) loci as well as the Sr25 and Sdl loci. The relative distances between marker loci on the translocation were then calculated. The information was then used as an aid to characterize several recombined forms of the translocation. The data confirmed the reported homoeology between the Lr19 segment and chromosome arm 7DL of wheat. Also, it seems that the Lr19 translocation in 'Indis' is very similar to the Lr19 segment in the T4 source and that the former may not derive from Thinopyrum distichum. Near-isogenic lines of the recombined segments were derived and used to study their expression of leaf rust resistance. It became evident that only one potentially useful recombinant was obtained in an earlier attempt to induce allosyndetic pairing between the Lr19 translocation and 7DL of wheat. (author)

  10. All-Atom Molecular Dynamics Simulation of Protein Translocation through an α-Hemolysin Nanopore

    KAUST Repository

    Di Marino, Daniele; Bonome, Emma Letizia; Tramontano, Anna; Chinappi, Mauro

    2015-01-01

    © 2015 American Chemical Society. Nanopore sensing is attracting the attention of a large and varied scientific community. One of the main issues in nanopore sensing is how to associate the measured current signals to specific features of the molecule under investigation. This is particularly relevant when the translocating molecule is a protein and the pore is sufficiently narrow to necessarily involve unfolding of the translocating protein. Recent experimental results characterized the cotranslocational unfolding of Thioredoxin (Trx) passing through an α-hemolisin pore, providing evidence for the existence of a multistep process. In this study we report the results of all-atom molecular dynamics simulations of the same system. Our data indicate that Trx translocation involves two main barriers. The first one is an unfolding barrier associated with a translocation intermediate where the N-terminal region of Trx is stuck at the pore entrance in a conformation that strongly resembles the native one. After the abrupt unfolding of the N-terminal region, the Trx enters the α-hemolisin vestibule. During this stage, the constriction is occupied not only by the translocating residue but also by a hairpin-like structure forming a tangle in the constriction. The second barrier is associated with the disentangling of this region.

  11. Production of reciprocal translocation lines and genetical analysis of tetravalent behavior in barley

    International Nuclear Information System (INIS)

    Makino, Tokuhiko

    1988-01-01

    The seeds of a barley cultivar, Chikurinibaraki No.1 and of an early mutant line, Ea 52, derived from it were exposed to the external irradiation of gamma ray and thermal neutrons, and to the internal irradiation with the alpha ray from the nuclear reaction B-10 (n, alpha) Li-7 generated by the thermal neutron irradiation of B-10 imbibed seeds. The reciprocal translocation induced by these irradiation was detected and bred in the pedigrees of irradiated materials by the selection in terms of the partial sterility of seeds. The examination of seed fertility and chromosome pairing at the MI of meiosis of the F 1 hybrid between the selected lines and the original cultivar was also used. Consequently, 50 homozygous lines of reciprocal translocation were confirmed. The tester lines for translocated chromosomes were established by the cytological examination of the chromosome pairing in the hybrids between each two of the tester lines. The investigation of the inheritance of translocation heterozygotes showed that most of the newly obtained lines differently behaved from the expectation on the genetical basis of reciprocal translocation. (Kako, I.)

  12. Autism Spectrum Disorder in a Girl with a De Novo X;19 Balanced Translocation

    Science.gov (United States)

    Baruffi, Marcelo Razera; de Souza, Deise Helena; Bicudo da Silva, Rosana Aparecida; Ramos, Ester Silveira; Moretti-Ferreira, Danilo

    2012-01-01

    Balanced X-autosome translocations are rare, and female carriers are a clinically heterogeneous group of patients, with phenotypically normal women, history of recurrent miscarriage, gonadal dysfunction, X-linked disorders or congenital abnormalities, and/or developmental delay. We investigated a patient with a de novo X;19 translocation. The six-year-old girl has been evaluated due to hyperactivity, social interaction impairment, stereotypic and repetitive use of language with echolalia, failure to follow parents/caretakers orders, inconsolable outbursts, and persistent preoccupation with parts of objects. The girl has normal cognitive function. Her measurements are within normal range, and no other abnormalities were found during physical, neurological, or dysmorphological examinations. Conventional cytogenetic analysis showed a de novo balanced translocation, with the karyotype 46,X,t(X;19)(p21.2;q13.4). Replication banding showed a clear preference for inactivation of the normal X chromosome. The translocation was confirmed by FISH and Spectral Karyotyping (SKY). Although abnormal phenotypes associated with de novo balanced chromosomal rearrangements may be the result of disruption of a gene at one of the breakpoints, submicroscopic deletion or duplication, or a position effect, X; autosomal translocations are associated with additional unique risk factors including X-linked disorders, functional autosomal monosomy, or functional X chromosome disomy resulting from the complex X-inactivation process. PMID:23074688

  13. Autism Spectrum Disorder in a Girl with a De Novo X;19 Balanced Translocation

    Directory of Open Access Journals (Sweden)

    Marcelo Razera Baruffi

    2012-01-01

    Full Text Available Balanced X-autosome translocations are rare, and female carriers are a clinically heterogeneous group of patients, with phenotypically normal women, history of recurrent miscarriage, gonadal dysfunction, X-linked disorders or congenital abnormalities, and/or developmental delay. We investigated a patient with a de novo X;19 translocation. The six-year-old girl has been evaluated due to hyperactivity, social interaction impairment, stereotypic and repetitive use of language with echolalia, failure to follow parents/caretakers orders, inconsolable outbursts, and persistent preoccupation with parts of objects. The girl has normal cognitive function. Her measurements are within normal range, and no other abnormalities were found during physical, neurological, or dysmorphological examinations. Conventional cytogenetic analysis showed a de novo balanced translocation, with the karyotype 46,X,t(X;19(p21.2;q13.4. Replication banding showed a clear preference for inactivation of the normal X chromosome. The translocation was confirmed by FISH and Spectral Karyotyping (SKY. Although abnormal phenotypes associated with de novo balanced chromosomal rearrangements may be the result of disruption of a gene at one of the breakpoints, submicroscopic deletion or duplication, or a position effect, X; autosomal translocations are associated with additional unique risk factors including X-linked disorders, functional autosomal monosomy, or functional X chromosome disomy resulting from the complex X-inactivation process.

  14. Pregnancy outcomes following 24-chromosome preimplantation genetic diagnosis in couples with balanced reciprocal or Robertsonian translocations.

    Science.gov (United States)

    Idowu, Dennis; Merrion, Katrina; Wemmer, Nina; Mash, Janine Gessner; Pettersen, Barbara; Kijacic, Dusan; Lathi, Ruth B

    2015-04-01

    To report live birth rates (LBR) and total aneuploidy rates in a series of patients with balanced translocations who pursued in vitro fertilization (IVF)-preimplantation genetic diagnosis (PGD) cycles. Retrospective cohort analysis. Genetic testing reference laboratory. Seventy-four couples who underwent IVF-PGD due to a parental translocation. IVF cycles and embryo biopsies were performed by referring clinics. Biopsy samples were sent to a single reference lab for PGD for the translocation plus 24-chromosome aneuploidy screening with the use of a single-nucleotide polymorphism (SNP) microarray. LBR per biopsy cycle, aneuploidy rate, embryo transfer (ET) rate, miscarriage rate. The LBR per IVF biopsy cycle was 38%. LBR for patients reaching ET was 52%. Clinical miscarriage rate was 10%. Despite a mean age of 33.8 years and mean of 7 embryos biopsied, there was a 30% chance for no chromosomally normal embryos. Maternal age >35 years, day 3 biopsy, and having fewer than five embryos available for biopsy increased the risk of no ET. IVF-PGD for translocation and aneuploidy screening had good clinical outcomes. Patients carrying a balanced translocation who are considering IVF-PGD should be aware of the high risk of no ET, particularly in women ≥35 years old. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  15. A recurrent translocation is mediated by homologous recombination between HERV-H elements

    Directory of Open Access Journals (Sweden)

    Hermetz Karen E

    2012-01-01

    Full Text Available Abstract Background Chromosome rearrangements are caused by many mutational mechanisms; of these, recurrent rearrangements can be particularly informative for teasing apart DNA sequence-specific factors. Some recurrent translocations are mediated by homologous recombination between large blocks of segmental duplications on different chromosomes. Here we describe a recurrent unbalanced translocation casued by recombination between shorter homologous regions on chromosomes 4 and 18 in two unrelated children with intellectual disability. Results Array CGH resolved the breakpoints of the 6.97-Megabase (Mb loss of 18q and the 7.30-Mb gain of 4q. Sequencing across the translocation breakpoints revealed that both translocations occurred between 92%-identical human endogenous retrovirus (HERV elements in the same orientation on chromosomes 4 and 18. In addition, we find sequence variation in the chromosome 4 HERV that makes one allele more like the chromosome 18 HERV. Conclusions Homologous recombination between HERVs on the same chromosome is known to cause chromosome deletions, but this is the first report of interchromosomal HERV-HERV recombination leading to a translocation. It is possible that normal sequence variation in substrates of non-allelic homologous recombination (NAHR affects the alignment of recombining segments and influences the propensity to chromosome rearrangement.

  16. Effects of arbuscular mycorrhizal fungi on the root uptake and translocation of radiocaesium

    International Nuclear Information System (INIS)

    Dupre de Boulois, Herve; Delvaux, Bruno; Declerck, Stephane

    2005-01-01

    Because mycorrhizal fungi are intimately associated with plant roots, their importance in radionuclide (RN) recycling and subsequent dispersion into the biosphere has received an increasing interest. Recently, the capacity of arbuscular mycorrhizal fungi to take up and translocate radiocaesium to their host was demonstrated. However, the relative contribution of these processes in comparison to the ones of roots remains unknown. Here, the respective contributions of the hyphae of a Glomus species and the transformed carrot (Daucus carota L.) roots on radiocaesium uptake and translocation were compared and quantified. We observed that radiocaesium uptake by hyphae was significantly lower as compared to that of the roots, while the opposite was noted for radiocaesium translocation/uptake ratio. We also observed that the intraradical fungal structures might induce a local accumulation of radiocaesium and concurrently reduce its translocation within mycorrhizal roots. We believe that intraradical fungal structures might induce the down-regulation of radiocaesium channels involved in the transport processes of radiocaesium towards the xylem. - Radiocaesium root uptake and translocation is affected by an arbuscular mycorrhizal fungus

  17. Effects of arbuscular mycorrhizal fungi on the root uptake and translocation of radiocaesium

    Energy Technology Data Exchange (ETDEWEB)

    Dupre de Boulois, Herve [Universite catholique de Louvain, Mycotheque de l' Universite catholique de Louvain (MUCL), Unite de Microbiologie, Place Croix du Sud 3, 1348 Louvain-la-Neuve (Belgium); Delvaux, Bruno [Universite catholique de Louvain, Unite des Sciences du Sol, Place Croix du Sud 2/10, 1348 Louvain-la-Neuve (Belgium); Declerck, Stephane [Universite catholique de Louvain, Mycotheque de l' Universite catholique de Louvain (MUCL), Unite de Microbiologie, Place Croix du Sud 3, 1348 Louvain-la-Neuve (Belgium)]. E-mail: declerck@mbla.ucl.ac.be

    2005-04-01

    Because mycorrhizal fungi are intimately associated with plant roots, their importance in radionuclide (RN) recycling and subsequent dispersion into the biosphere has received an increasing interest. Recently, the capacity of arbuscular mycorrhizal fungi to take up and translocate radiocaesium to their host was demonstrated. However, the relative contribution of these processes in comparison to the ones of roots remains unknown. Here, the respective contributions of the hyphae of a Glomus species and the transformed carrot (Daucus carota L.) roots on radiocaesium uptake and translocation were compared and quantified. We observed that radiocaesium uptake by hyphae was significantly lower as compared to that of the roots, while the opposite was noted for radiocaesium translocation/uptake ratio. We also observed that the intraradical fungal structures might induce a local accumulation of radiocaesium and concurrently reduce its translocation within mycorrhizal roots. We believe that intraradical fungal structures might induce the down-regulation of radiocaesium channels involved in the transport processes of radiocaesium towards the xylem. - Radiocaesium root uptake and translocation is affected by an arbuscular mycorrhizal fungus.

  18. Local traction force in the proximal leading process triggers nuclear translocation during neuronal migration.

    Science.gov (United States)

    Umeshima, Hiroki; Nomura, Ken-Ichi; Yoshikawa, Shuhei; Hörning, Marcel; Tanaka, Motomu; Sakuma, Shinya; Arai, Fumihito; Kaneko, Makoto; Kengaku, Mineko

    2018-04-05

    Somal translocation in long bipolar neurons is regulated by actomyosin contractile forces, yet the precise spatiotemporal sites of force generation are unknown. Here we investigate the force dynamics generated during somal translocation using traction force microscopy. Neurons with a short leading process generated a traction force in the growth cone and counteracting forces in the leading and trailing processes. In contrast, neurons with a long leading process generated a force dipole with opposing traction forces in the proximal leading process during nuclear translocation. Transient accumulation of actin filaments was observed at the dipole center of the two opposing forces, which was abolished by inhibition of myosin II activity. A swelling in the leading process emerged and generated a traction force that pulled the nucleus when nuclear translocation was physically hampered. The traction force in the leading process swelling was uncoupled from somal translocation in neurons expressing a dominant negative mutant of the KASH protein, which disrupts the interaction between cytoskeletal components and the nuclear envelope. Our results suggest that the leading process is the site of generation of actomyosin-dependent traction force in long bipolar neurons, and that the traction force is transmitted to the nucleus via KASH proteins. Copyright © 2018 Elsevier B.V. and Japan Neuroscience Society. All rights reserved.

  19. Follow-up of translocations and dicentrics by chromosome painting (Fish) after accidental exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Lindhom, C.; Salomaa, S.; Tekkel, M.; Veidebaum, T.

    1997-01-01

    Chromosome painting was applied to follow the frequencies of translocations and dicentrics in blood lymphocytes from eight persons involved in a radiation accident in Estonia, 1994. Complete translocation frequencies remained relatively constant during the first year of study, whereas the rate of complete dicentrics declined rapidly in patients exposed to 1 Gy or more. The high proportion of incomplete translocations observed right after the accident declined during the first year after the exposure, approaching the level of incomplete dicentrics. (authors)

  20. Optimization of the Expression of DT386-BR2 Fusion Protein in Escherichia coli using Response Surface Methodology.

    Science.gov (United States)

    Shafiee, Fatemeh; Rabbani, Mohammad; Jahanian-Najafabadi, Ali

    2017-01-01

    The aim of this study was to determine the best condition for the production of DT386-BR2 fusion protein, an immunotoxin consisting of catalytic and translocation domains of diphtheria toxin fused to BR2, a cancer specific cell penetrating peptide, for targeted eradication of cancer cells, in terms of the host, cultivation condition, and culture medium. Recombinant pET28a vector containing the codons optimized for the expression of the DT386-BR2 gene was transformed to different strains of Escherichia coli ( E. coli BL21 DE3, E. coli Rosetta DE3 and E. coli Rosetta-gami 2 DE3), followed by the induction of expression using 1 mM IPTG. Then, the strain with the highest ability to produce recombinant protein was selected and used to determine the best expression condition using response surface methodology (RSM). Finally, the best culture medium was selected. Densitometry analysis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the expressed fusion protein showed that E. coli Rosetta DE3 produced the highest amounts of the recombinant fusion protein when quantified by 1 mg/ml bovine serum albumin (178.07 μg/ml). Results of RSM also showed the best condition for the production of the recombinant fusion protein was induction with 1 mM IPTG for 2 h at 37°C. Finally, it was established that terrific broth could produce higher amounts of the fusion protein when compared to other culture media. In this study, we expressed the recombinant DT386-BR2 fusion protein in large amounts by optimizing the expression host, cultivation condition, and culture medium. This fusion protein will be subjected to purification and evaluation of its cytotoxic effects in future studies.

  1. Optimization of the Expression of DT386-BR2 Fusion Protein in Escherichia coli using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Fatemeh Shafiee

    2017-01-01

    Full Text Available Background: The aim of this study was to determine the best condition for the production of DT386-BR2 fusion protein, an immunotoxin consisting of catalytic and translocation domains of diphtheria toxin fused to BR2, a cancer specific cell penetrating peptide, for targeted eradication of cancer cells, in terms of the host, cultivation condition, and culture medium. Materials and Methods: Recombinant pET28a vector containing the codons optimized for the expression of the DT386-BR2 gene was transformed to different strains of Escherichia coli (E. coli BL21 DE3, E. coli Rosetta DE3 and E. coli Rosetta-gami 2 DE3, followed by the induction of expression using 1 mM IPTG. Then, the strain with the highest ability to produce recombinant protein was selected and used to determine the best expression condition using response surface methodology (RSM. Finally, the best culture medium was selected. Results: Densitometry analysis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the expressed fusion protein showed that E. coli Rosetta DE3 produced the highest amounts of the recombinant fusion protein when quantified by 1 mg/ml bovine serum albumin (178.07 μg/ml. Results of RSM also showed the best condition for the production of the recombinant fusion protein was induction with 1 mM IPTG for 2 h at 37°C. Finally, it was established that terrific broth could produce higher amounts of the fusion protein when compared to other culture media. Conclusion: In this study, we expressed the recombinant DT386-BR2 fusion protein in large amounts by optimizing the expression host, cultivation condition, and culture medium. This fusion protein will be subjected to purification and evaluation of its cytotoxic effects in future studies.

  2. Infectious endocarditis caused by Escherichia coli

    DEFF Research Database (Denmark)

    Lauridsen, Trine Kiilerich; Arpi, Magnus; Fritz-Hansen, Thomas

    2011-01-01

    Although Escherichia coli is among the most common causes of Gram-negative bacteraemia, infectious endocarditis (IE) due to this pathogen is rare. A 67-y-old male without a previous medical history presented with a new mitral regurgitation murmur and persisting E. coli bacteraemia in spite of broad......-spectrum intravenous antibiotics. Transthoracic and transoesophageal echocardiography revealed a severe mitral endocarditis. E. coli DNA was identified from the mitral valve and the vegetation, and no other pathogen was found. The case was further complicated by spondylodiscitis and bilateral endophthalmitis. Extra...

  3. Survival of pathogenic Escherichia coli on basil, lettuce, and spinach

    Science.gov (United States)

    The contamination of lettuce, spinach and basil with pathogenic E. coli has caused numerous illnesses over the past decade. E. coli O157:H7, E. coli O104:H4 and avian pathogenic E. coli (APECstx- and APECstx+) were inoculated on basil plants and in promix soiless substrate using drip and overhead ir...

  4. 21 CFR 866.3255 - Escherichia coli serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Escherichia coli serological reagents. 866.3255... coli serological reagents. (a) Identification. Escherichia coli serological reagents are devices that consist of antigens and antisera used in serological tests to identify Escherichia coli from cultured...

  5. A scoping study on the prevalence of Escherichia coli and ...

    African Journals Online (AJOL)

    In the Eastern Cape Province E. coli and enterococci were detected in 7 and 4 of the 15 RHRW tanks, respectively. Enterococci were detected only from one river whereas E. coli was detected in all three rivers; in spring water neither enterococci nor E. coli were detected. Samples from GRWH tanks were positive for E. coli ...

  6. Comparison between fluorescent in-situ hybridisation and array comparative genomic hybridisation in preimplantation genetic diagnosis in translocation carriers.

    Science.gov (United States)

    Lee, Vivian C Y; Chow, Judy F C; Lau, Estella Y L; Yeung, William S B; Ho, P C; Ng, Ernest H Y

    2015-02-01

    To compare the pregnancy outcome of the fluorescent in-situ hybridisation and array comparative genomic hybridisation in preimplantation genetic diagnosis of translocation carriers. Historical cohort. A teaching hospital in Hong Kong. All preimplantation genetic diagnosis treatment cycles performed for translocation carriers from 2001 to 2013. Overall, 101 treatment cycles for preimplantation genetic diagnosis in translocation were included: 77 cycles for reciprocal translocation and 24 cycles for Robertsonian translocation. Fluorescent in-situ hybridisation and array comparative genomic hybridisation were used in 78 and 11 cycles, respectively. The ongoing pregnancy rate per initiated cycle after array comparative genomic hybridisation was significantly higher than that after fluorescent in-situ hybridisation in all translocation carriers (36.4% vs 9.0%; P=0.010). The miscarriage rate was comparable with both techniques. The testing method (array comparative genomic hybridisation or fluorescent in-situ hybridisation) was the only significant factor affecting the ongoing pregnancy rate after controlling for the women's age, type of translocation, and clinical information of the preimplantation genetic diagnosis cycles by logistic regression (odds ratio=1.875; P=0.023; 95% confidence interval, 1.090-3.226). This local retrospective study confirmed that comparative genomic hybridisation is associated with significantly higher pregnancy rates versus fluorescent in-situ hybridisation in translocation carriers. Array comparative genomic hybridisation should be the technique of choice in preimplantation genetic diagnosis cycles in translocation carriers.

  7. Protective effects of indigenous Escherichia coli against a pathogenic E. coli challenge strain in pigs.

    Science.gov (United States)

    Vahjen, W; Cuisiniere, T; Zentek, J

    2017-10-13

    To investigate the inhibitory effect of indigenous enterobacteria on pathogenic Escherichia coli, a challenge trial with postweaning pigs was conducted. A pathogenic E. coli strain was administered to all animals and their health was closely monitored thereafter. Faecal samples were taken from three healthy and three diarrhoeic animals. Samples were cultivated on MacConkey agar and isolates were subcultured. A soft agar overlay assay was used to determine the inhibitory activity of the isolates. A total of 1,173 enterobacterial isolates were screened for their ability to inhibit the E. coli challenge strain. Colony forming units of enterobacteria on MacConkey agar were not different between healthy and diarrhoeic animals in the original samples. Furthermore, numbers of isolates per animal were also not significantly different between healthy (482 isolates) and diarrhoeic animals (691 isolates). A total of 43 isolates (3.7%) with inhibitory activity against the pathogenic E. coli challenge strain were detected. All inhibitory isolates were identified as E. coli via MALDI-TOF. The isolates belonged to the phylotypes A, C and E. Many isolates (67.4%) were commensal E. coli without relevant porcine pathogenic factors, but toxin- and fimbrial genes (stx2e, fae, estIb, elt1a, fas, fan) were detected in 14 inhibitory isolates. Healthy animals showed significantly (P=0.003) more inhibitory isolates (36 of 482 isolates; 7.5%) than diseased animals (7 of 691 isolates; 1.0%). There were no significant correlations regarding phylotype or pathogenic factors between healthy and diseased animals. This study has shown that a small proportion of indigenous E. coli is able to inhibit in vitro growth of a pathogenic E. coli strain in pigs. Furthermore, healthy animals possess significantly more inhibitory E. coli strains than diarrhoeic animals. The inhibition of pathogenic E. coli by specific indigenous E. coli strains may be an underlying principle for the containment of pathogenic

  8. γ-Ray-induced reciprocal translocations in spermatogonia of the crab-eating monkey (Macaca fascicularis)

    International Nuclear Information System (INIS)

    Matsuda, Y.; Tobari, I.; Yamagiwa, J.; Utsugi, T.; Kitazume, M.; Nakai, S.

    1984-01-01

    The yield of translocations induced by γ-rays in the crab-eating monkey (Macaca fascicularis) spermatogonia were studied by cytological analysis in spermatocytes derived from them. The frequencies of translocations were 0.09 per cent at 0 Gy, 1.9 per cent at 1 Gy, 2.5 per cent at 2 Gy and 1.3 per cent at 3 Gy, showing a humped dose-response curve with a peak yield around 2 Gy. No remarkable inter-seasonal or inter-animal variations in the induction of translocation were observed. The frequencies in the crab-eating monkey were significantly higher than those in the same Macaca genus, the rhesus monkey (Macaca mulatta). This inter-species difference in radiosensitivity might be affected by the condition of spermatogonial stem cells at the time of exposure to radiation, depending on the seasonal change in spermatogenetic activity. (orig.)

  9. Influence of cycloheximide on translocation of 32P in Laminaria digitata (Linne) Lamouroux

    International Nuclear Information System (INIS)

    Floc'h, J.Y.; Penot, M.

    1978-01-01

    Cycloheximide strongly reduced translocation of 32 P when applied to various regions of Laminaria digitata thallus. In addition, the part of the different organs is demonstrated. The results show that CHM action was restricted to the treated zone since 32 P migrations were not reduced in surrounding regions. At the same time, CHM influence on other metabolic processes possibly involved in translocation, was studied. Thus, as concerns 32 P uptake by thallus pieces, CHM inhibition took effect but after a 4 hour action period. Moreover, no effect on O 2 uptake was observed. These results are believed to favour an inhibitory action on protein synthesis more than to affect oxidative phosphorylations. The present data are considered to support the view that in algae as well as in higher plants, the mechanisms of the translocation of inorganic substances depend on the protein metabolism. (orig.) [de

  10. Studies on the translocation of Cs-134 from leaves to fruit of apple trees

    International Nuclear Information System (INIS)

    Katana, H.; Bunnenberg, C.; Kuehn, W.

    1988-01-01

    Besides the commonly considered pathway of radionulides into plant products, namely root uptake and surface deposition, another contamination process of edible parts of plants may occur when activity is intercepted by exposed plant surfaces and translocated within the plant into the fruit under consideration. This pathway seems especially relevant in case of fruit trees having large total leaf areas compared to the actual fruit surface. Besides the plant species and the nutritive element the most relevant parameters of the uptake and translocation efficiencies seem to be the age and the time and way of application, where these parameters include a number of sub-parameters. The present studies concern the translocation of cesium in apple tress from differently labeled plant parts into fruit in view of its possible contribution to fruit contamination

  11. Identification of genome-specific transcripts in wheat–rye translocation lines

    Directory of Open Access Journals (Sweden)

    Tong Geon Lee

    2015-09-01

    Full Text Available Studying gene expression in wheat–rye translocation lines is complicated due to the presence of homeologs in hexaploid wheat and high levels of synteny between wheat and rye genomes (Naranjo and Fernandez-Rueda, 1991 [1]; Devos et al., 1995 [2]; Lee et al., 2010 [3]; Lee et al., 2013 [4]. To overcome limitations of current gene expression studies on wheat–rye translocation lines and identify genome-specific transcripts, we developed a custom Roche NimbleGen Gene Expression microarray that contains probes derived from the sequence of hexaploid wheat, diploid rye and diploid progenitors of hexaploid wheat genome (Lee et al., 2014. Using the array developed, we identified genome-specific transcripts in a wheat–rye translocation line (Lee et al., 2014. Expression data are deposited in the NCBI Gene Expression Omnibus (GEO under accession number GSE58678. Here we report the details of the methods used in the array workflow and data analysis.

  12. Transfer of alien genes by means of induced translocation in oats and other crop species

    International Nuclear Information System (INIS)

    Thomas, H.; Taing Aung

    1977-01-01

    Some of the best sources of resistance to mildew, which is the most important disease of the oat crop in the United Kingdom, occur in related weed species. The mildew resistance found in a genotype of the tetraploid species Avena barbata has been transferred into the germ plasm of the cultivated hexaploid species A. sativa by means of an induced translocation. The procedures adopted to isolate the desirable translocation and to determine its breeding behaviour are described. A number of alien genes have been transferred into wheat by means of induced translocations and genetic induction, but their successful introduction into commercial varieties has been limited. In this paper, the use and limitations of alien transfers as breeding material are discussed. (author)

  13. Kinetics of contraction-induced GLUT4 translocation in skeletal muscle fibers from living mice

    DEFF Research Database (Denmark)

    Lauritzen, Hans Peter M. Mortensen; Galbo, Henrik; Toyoda, Taro

    2010-01-01

    Exercise is an important strategy for the treatment of type 2 diabetes. This is due in part to an increase in glucose transport that occurs in the working skeletal muscles. Glucose transport is regulated by GLUT4 translocation in muscle, but the molecular machinery mediating this process is poorl...... understood. The purpose of this study was to 1) use a novel imaging system to elucidate the kinetics of contraction-induced GLUT4 translocation in skeletal muscle and 2) determine the function of AMP-activated protein kinase alpha2 (AMPKalpha2) in this process.......Exercise is an important strategy for the treatment of type 2 diabetes. This is due in part to an increase in glucose transport that occurs in the working skeletal muscles. Glucose transport is regulated by GLUT4 translocation in muscle, but the molecular machinery mediating this process is poorly...

  14. Assessment of an in vitro model of pulmonary barrier to study the translocation of nanoparticles

    Directory of Open Access Journals (Sweden)

    Samir Dekali

    2014-01-01

    The use of Calu-3 cells allowed high transepithelial electrical resistance (TEER values (>1000 Ω cm2 in co-cultures with or without macrophages. After 24 h of exposure to non-cytotoxic concentrations of non-functionalized PS nanobeads, the relative TEER values (%/t0 were significantly decreased in co-cultures. Epithelial cells and macrophages were able to internalize PS nanobeads. Regarding translocation, Transwell® membranes per se limit the passage of nanoparticles between apical and basal side. However, small non-functionalized PS nanobeads (51 nm were able to translocate as they were detected in the basal side of co-cultures. Altogether, these results show that this co-culture model present good barrier properties allowing the study of nanoparticle translocation but research effort need to be done to improve the neutrality of the porous membrane delimitating apical and basal sides of the model.

  15. The effect of using a "soft" release on translocation success of red-cockaded woodpeckers.

    Energy Technology Data Exchange (ETDEWEB)

    Franzreb, Kathleen, E.

    2004-12-31

    Franzreb, Kathleen, E. 2004 The effect of using a "soft" release on translocation success of red-cockaded woodpeckers. In: Red-cockaded woodpecker; Road to Recovery. Proceedings of the 4th Red-cockaded woodpecker Symposium. Ralph Costa and Susan J. Daniels, eds. Savannah, Georgia. January, 2003. Chapter 6. Translocation. Pp 301-306. Abstract: Translocations of the endangered red-cockaded woodpecker have been conducted since 1986 to enhance critically small subpopulations, to minimize the likelihood of local extirpations, and to reduce the adverse effects of fragmentation and isolation among existing populations. Such attempts have had mixed success. This article compares "hard" releases with a "soft" release technique where the birds are temporarily interned in a large aviary at the release point for a period of 9 to 14 days.

  16. Interleukin-2 induces tyrosine phosphorylation and nuclear translocation of stat3 in human T lymphocytes

    DEFF Research Database (Denmark)

    Nielsen, M; Svejgaard, A; Skov, S

    1994-01-01

    that stimulation through the IL-2R induced tyrosine phosphorylation and subsequent nuclear translocation of stat3, a newly identified member of the signal transducers and activators of transcription (STAT) family of proteins. In contrast, stat1 proteins were not tyrosine phosphorylated after IL-2 ligation, whereas...... an apparent molecular mass of 84 kDa and was not recognized by stat3 or stat1 mAb or antisera. Since IL-2 induced nuclear translocation of the 84 kDa protein and stat3 followed identical kinetics, p84 is a candidate for a new, yet undefined, member of the STAT family. Taken together, we report that IL-2...... induces tyrosine phosphorylation and subsequent nuclear translocation of stat3 and an as yet undefined 84-kDa protein in antigen-specific human T cell lines....

  17. Chromosome 2 short arm translocations revealed by M-FISH analysis of neuroblastoma cell lines.

    Science.gov (United States)

    Van Roy, N; Van Limbergen, H; Vandesompele, J; Van Gele, M; Poppe, B; Laureys, G; De Paepe, A; Speleman, F

    2000-12-01

    M-FISH analysis was performed on 18 neuroblastoma cell lines, which were previously studied with cytogenetic, standard FISH and CGH data. One of the most striking findings of this study was the detection of chromosome 2 short arm rearrangements in 61% of the investigated cell lines. These rearrangements resulted from translocations with various partner chromosomes. All translocations, except one were unbalanced, leading to the consistent gain of chromosome segment 2pter-p22. A cryptic balanced translocation t(2;4) was observed with a breakpoint located in the vicinity of MYCN in cell line NBL-S. Combination of M-FISH results together with cytogenetic, standard FISH and CGH data yielded the most comprehensive description of chromosome 2 short arm rearrangements, leading to a consistent gain of chromosome 2 short arm material. Copyright 2000 Wiley-Liss, Inc.

  18. Amplification of chromosomal translocation junctions from paraffin-embedded tissues of follicular lymphoma patients

    International Nuclear Information System (INIS)

    Nambiar, Mridula; Raghavan, Sathees C; Choudhary, Bibha; Rao, Clementina R

    2008-01-01

    Follicular lymphoma is associated with the t(14;18) translocation, which is one of the most common chromosomal translocations in cancer. Generally, tissues from such patients are preserved as formalin-fixed and paraffin-embedded samples. Most of the time, retrieving the molecular information from such samples is hampered due to quality of preservation, extraction procedures and reaction conditions. In the present study, we isolate the chromosomal DNA from the paraffin-embedded nodal tissues of lymphoma patients and use a highly sensitive nested PCR approach to detect t(14;18) translocation. Our studies show that despite the sheared DNA obtained, appropriate modification of PCR reaction conditions can help in obtaining the desired amplifications. The DNA extraction protocol from paraffin-embedded nodal tissues and modifications in the PCR conditions are discussed. This study would contribute to the successful use of archival tissue samples in obtaining valuable information for cancer research

  19. Amplification of chromosomal translocation junctions from paraffin-embedded tissues of follicular lymphoma patients

    Energy Technology Data Exchange (ETDEWEB)

    Nambiar, Mridula; Raghavan, Sathees C [Department of Biochemistry, Indian Institute of Science, Bangalore-560 012 (India); Choudhary, Bibha [Manipal Institute of Regenerative Medicine, Manipal University, Bangalore-560 071 (India); Rao, Clementina R [Department of Pathology, Kidwai Memorial Institute of Oncology, Bangalore-560 029 (India)], E-mail: sathees@biochem.iisc.ernet.in

    2008-09-01

    Follicular lymphoma is associated with the t(14;18) translocation, which is one of the most common chromosomal translocations in cancer. Generally, tissues from such patients are preserved as formalin-fixed and paraffin-embedded samples. Most of the time, retrieving the molecular information from such samples is hampered due to quality of preservation, extraction procedures and reaction conditions. In the present study, we isolate the chromosomal DNA from the paraffin-embedded nodal tissues of lymphoma patients and use a highly sensitive nested PCR approach to detect t(14;18) translocation. Our studies show that despite the sheared DNA obtained, appropriate modification of PCR reaction conditions can help in obtaining the desired amplifications. The DNA extraction protocol from paraffin-embedded nodal tissues and modifications in the PCR conditions are discussed. This study would contribute to the successful use of archival tissue samples in obtaining valuable information for cancer research.

  20. (ESBL) producing Escherichia coli and Klebsiella pneumoniae

    African Journals Online (AJOL)

    use

    2011-11-21

    Nov 21, 2011 ... the most common serious bacterial infections in infants ... UTI is a common cause of morbidity .... of ESBL and non-ESBL producing Escherichia coli and Klebsiella pneumonia. ... in hospital and community acquired infections.

  1. FTIR nanobiosensors for Escherichia coli detection

    Directory of Open Access Journals (Sweden)

    Stefania Mura

    2012-07-01

    Full Text Available Infections due to enterohaemorrhagic E. coli (Escherichia coli have a low incidence but can have severe and sometimes fatal health consequences, and thus represent some of the most serious diseases due to the contamination of water and food. New, fast and simple devices that monitor these pathogens are necessary to improve the safety of our food supply chain. In this work we report on mesoporous titania thin-film substrates as sensors to detect E. coli O157:H7. Titania films treated with APTES ((3-aminopropyltriethoxysilane and GA (glutaraldehyde were functionalized with specific antibodies and the absorption properties monitored. The film-based biosensors showed a detection limit for E. coli of 1 × 102 CFU/mL, constituting a simple and selective method for the effective screening of water samples.

  2. Escherichia coli pyomyositis in an immunocompromised host.

    Science.gov (United States)

    Sharma, Umesh; Schwan, William R; Agger, William A

    2011-08-01

    Pyomyositis due to Escherichia coli (E. coil) is rarely reported in immunocompromised patients with hematological malignancy. We present a case report of a 34-year-old man who developed E. coli pyomyositis as a complication of acute myelogenous leukemia (AML). Magnetic resonance imaging (MRI) of the right hip suggested myofascial infection of the gluteal muscles, and a needle muscle aspiration grew E. coli phylogenetic group B2. The patient responded to intravenous piperacillin/tazobactam followed by prolonged oral levofloxacin. Pyomyositis should be suspected in all immunocompromised patients complaining of muscle pain and may exhibit signs of localized muscle infection. Appropriate antibiotic therapy targeting fluoroquinolone-resistant E. coli should be considered for initial empiric therapy of pyomyositis in immunocompromised patients.

  3. Characterization of Escherichia coli Phylogenetic Groups ...

    African Journals Online (AJOL)

    tract infection (UTI), bacteremia, pneumonia, soft-tissue infection, and ... Keywords: Drug resistance, Escherichia coli, Extraintestinal infections, Polymerase chain reaction, .... gynecology, 12 from orthopedics and 5 from pediatrics units.

  4. Infectious endocarditis caused by Escherichia coli

    DEFF Research Database (Denmark)

    Lauridsen, Trine Kiilerich; Arpi, Magnus; Fritz-Hansen, Thomas

    2011-01-01

    Although Escherichia coli is among the most common causes of Gram-negative bacteraemia, infectious endocarditis (IE) due to this pathogen is rare. A 67-y-old male without a previous medical history presented with a new mitral regurgitation murmur and persisting E. coli bacteraemia in spite of broad......-spectrum intravenous antibiotics. Transthoracic and transoesophageal echocardiography revealed a severe mitral endocarditis. E. coli DNA was identified from the mitral valve and the vegetation, and no other pathogen was found. The case was further complicated by spondylodiscitis and bilateral endophthalmitis. Extra......-intestinal pathogenic E. coli (ExPEC) are able to colonize tissue outside the gastrointestinal tract and contain a variety of virulence factors that may enable the pathogens to invade and induce infections in the cardiac endothelia. In these cases echocardiography as the imaging technology is of paramount importance...

  5. Synergistic effects in mixed Escherichia coli biofilms

    DEFF Research Database (Denmark)

    Reisner, A.; Holler, B.M.; Molin, Søren

    2006-01-01

    Bacterial biofilms, often composed of multiple species and genetically distinct strains, develop under complex influences of cell-cell interactions. Although detailed knowledge about the mechanisms underlying formation of single-species laboratory biofilms has emerged, little is known about...... the pathways governing development of more complex heterogeneous communities. In this study, we established a laboratory model where biofilm-stimulating effects due to interactions between genetically diverse strains of Escherichia coli were monitored. Synergistic induction of biofilm formation resulting from...... the cocultivation of 403 undomesticated E. coli strains with a characterized E. coli K-12 strain was detected at a significant frequency. The survey suggests that different mechanisms underlie the observed stimulation, yet synergistic development of biofilm within the subset of E. coli isolates (n = 56) exhibiting...

  6. Experimental induced avian E. coli salpingitis

    DEFF Research Database (Denmark)

    Olsen, Rikke Heidemann; Thøfner, Ida; Pors, Susanne Elisabeth

    2016-01-01

    Several types of Escherichia coli have been associated with extra-intestinal infections in poultry, however, they may vary significantly in their virulence potential. The aim of the present study was to investigate the virulence of five strains of E. coli obtained from different disease......) had a distinct ability to cause disease. Results of the study shows major differences in virulence of different strains of E. coli in ascending infections; however, there was no indication of tissue-specific adaptation, since strains obtained from lesions unrelated to the reproductive system were...... fully capable of causing experimental infection. In conclusion, the study provides evidence for the clinical outcome of infection with E. coli in poultry is largely influenced by the specific strain as well as individual host factors....

  7. WARBURG EFFECT AND TRANSLOCATION-INDUCED GENOMIC INSTABILITY: TWO YEAST MODELS FOR CANCER CELLS

    Directory of Open Access Journals (Sweden)

    Valentina eTosato

    2013-01-01

    Full Text Available Yeast has been established as an efficient model system to study biological principles underpinning human health. In this review we focus on yeast models covering two aspects of cancer formation and progression i the activity of pyruvate kinase (PK, which recapitulates metabolic features of cancer cells, including the Warburg effect, and ii Bridge-Induced chromosome Translocation (BIT mimicking genome instability in cancer. Saccharomyces cerevisiae is an excellent model to study cancer cell metabolism, as exponentially growing yeast cells exhibit many metabolic similarities with rapidly proliferating cancer cells. The metabolic reconfiguration includes an increase in glucose uptake and fermentation, at the expense of respiration and oxidative phosphorylation (the Warburg effect, and involves a broad reconfiguration of nucleotide and amino acid metabolism. Both in yeast and humans, the regulation of this process seems to have a central player, pyruvate kinase, which is up-regulated in cancer, and to occur mostly on a post-transcriptional and posttranslational basis. Furthermore, BIT allows to generate selectable translocation-derived recombinants (translocants, between any two desired chromosomal locations, in wild-type yeast strains transformed with a linear DNA cassette carrying a selectable marker flanked by two DNA sequences homologous to different chromosomes. Using the Bridge-Induced Translocation system, targeted non-reciprocal translocations in mitosis are easily inducible. An extensive collection of different yeast translocants exhibiting genome instability and aberrant phenotypes similar to cancer cells has been produced and subjected to analysis. In this review, we hence provide an overview upon two yeast cancer models, and extrapolate general principles for mimicking human disease mechanisms in yeast.

  8. Rewilding the tropics, and other conservation translocations strategies in the tropical Asia-Pacific region

    Science.gov (United States)

    Louys, Julien; Corlett, Richard T; Price, Gilbert J; Hawkins, Stuart; Piper, Philip J

    2014-01-01

    Alarm over the prospects for survival of species in a rapidly changing world has encouraged discussion of translocation conservation strategies that move beyond the focus of ‘at-risk’ species. These approaches consider larger spatial and temporal scales than customary, with the aim of recreating functioning ecosystems through a combination of large-scale ecological restoration and species introductions. The term ‘rewilding’ has come to apply to this large-scale ecosystem restoration program. While reintroductions of species within their historical ranges have become standard conservation tools, introductions within known paleontological ranges—but outside historical ranges—are more controversial, as is the use of taxon substitutions for extinct species. Here, we consider possible conservation translocations for nine large-bodied taxa in tropical Asia-Pacific. We consider the entire spectrum of conservation translocation strategies as defined by the IUCN in addition to rewilding. The taxa considered are spread across diverse taxonomic and ecological spectra and all are listed as ‘endangered’ or ‘critically endangered’ by the IUCN in our region of study. They all have a written and fossil record that is sufficient to assess past changes in range, as well as ecological and environmental preferences, and the reasons for their decline, and they have all suffered massive range restrictions since the late Pleistocene. General principles, problems, and benefits of translocation strategies are reviewed as case studies. These allowed us to develop a conservation translocation matrix, with taxa scored for risk, benefit, and feasibility. Comparisons between taxa across this matrix indicated that orangutans, tapirs, Tasmanian devils, and perhaps tortoises are the most viable taxa for translocations. However, overall the case studies revealed a need for more data and research for all taxa, and their ecological and environmental needs. Rewilding the Asian

  9. Chromosomal Translocations in Black Flies (Diptera: Simuliidae-Facilitators of Adaptive Radiation?

    Directory of Open Access Journals (Sweden)

    Peter H Adler

    Full Text Available A macrogenomic investigation of a Holarctic clade of black flies-the Simulium cholodkovskii lineage-provided a platform to explore the implications of a unique, synapomorphic whole-arm interchange in the evolution of black flies. Nearly 60 structural rearrangements were discovered in the polytene complement of the lineage, including 15 common to all 138 analyzed individuals, relative to the central sequence for the entire subgenus Simulium. Three species were represented, of which two Palearctic entities (Simulium cholodkovskii and S. decimatum were sympatric; an absence of hybrids confirmed their reproductive isolation. A third (Nearctic entity had nonhomologous sex chromosomes, relative to the other species, and is considered a separate species, for which the name Simulium nigricoxum is revalidated. A cytophylogeny is inferred and indicates that the two Palearctic taxa are sister species and these, in turn, are the sister group of the Nearctic species. The rise of the S. cholodkovskii lineage encompassed complex chromosomal and genomic restructuring phenomena associated with speciation in black flies, viz. expression of one and the same rearrangement as polymorphic, fixed, or sex linked in different species; taxon-specific differentiation of sex chromosomes; and reciprocal translocation of chromosome arms. The translocation is hypothesized to have occurred early in male spermatogonia, with the translocated chromosomal complement being transmitted to the X- and Y-bearing sperm during spermatogenesis, resulting in alternate disjunction of viable F1 translocation heterozygotes and the eventual formation of more viable and selectable F2 translocation homozygous progeny. Of 11 or 12 independently derived whole-arm interchanges known in the family Simuliidae, at least six are associated with subsequent speciation events, suggesting a facilitating role of translocations in adaptive radiations. The findings are discussed in the context of potential

  10. Detection of zinc translocation into apical dendrite of CA1 pyramidal neuron after electrical stimulation.

    Science.gov (United States)

    Suh, Sang Won

    2009-02-15

    Translocation of the endogenous cation zinc from presynaptic terminals to postsynaptic neurons after brain insult has been implicated as a potential neurotoxic event. Several studies have previously demonstrated that a brief electrical stimulation is sufficient to induce the translocation of zinc from presynaptic vesicles into the cytoplasm (soma) of postsynaptic neurons. In the present work I have extended those findings in three ways: (i) providing evidence that zinc translocation occurs into apical dendrites, (ii) presenting data that there is an apparent translocation into apical dendrites when only a zinc-containing synaptic input is stimulated, and (iii) presenting data that there is no zinc translocation into apical dendrite of ZnT3 KO mice following electrical stimulation. Hippocampal slices were preloaded with the "trappable" zinc fluorescent probe, Newport Green. After washout, a single apical dendrite in the stratum radiatum of hippocampal CA1 area was selected and focused on. Burst stimulation (100Hz, 500microA, 0.2ms, monopolar) was delivered to either the adjacent Schaffer-collateral inputs (zinc-containing) or to the adjacent temporo-ammonic inputs (zinc-free) to the CA1 dendrites. Stimulation of the Schaffer collaterals increased the dendritic fluorescence, which was blocked by TTX, low-Ca medium, or the extracellular zinc chelator, CaEDTA. Stimulation of the temporo-ammonic pathway caused no significant rise in the fluorescence. Genetic depletion of vesicular zinc by ZnT3 KO showed no stimulation-induced apical dendrite zinc rise. The present study provides evidence that synaptically released zinc translocates into postsynaptic neurons through the apical dendrites of CA1 pyramidal neurons during physiological synaptic activity.

  11. ECMDB: The E. coli Metabolome Database

    OpenAIRE

    Guo, An Chi; Jewison, Timothy; Wilson, Michael; Liu, Yifeng; Knox, Craig; Djoumbou, Yannick; Lo, Patrick; Mandal, Rupasri; Krishnamurthy, Ram; Wishart, David S.

    2012-01-01

    The Escherichia coli Metabolome Database (ECMDB, http://www.ecmdb.ca) is a comprehensively annotated metabolomic database containing detailed information about the metabolome of E. coli (K-12). Modelled closely on the Human and Yeast Metabolome Databases, the ECMDB contains >2600 metabolites with links to ?1500 different genes and proteins, including enzymes and transporters. The information in the ECMDB has been collected from dozens of textbooks, journal articles and electronic databases. E...

  12. Contraction-associated translocation of protein kinase C in rat skeletal muscle

    DEFF Research Database (Denmark)

    Richter, Erik; Cleland, P J; Rattigan, S

    1987-01-01

    Electrical stimulation of the sciatic nerve of the anaesthetized rat in vivo led to a time-dependent translocation of protein kinase C from the muscle cytosol to the particulate fraction. Maximum activity of protein kinase C in the particulate fraction occurred after 2 min of intermittent short...... tetanic contractions of the gastrocnemius-plantaris-soleus muscle group and coincided with the loss of activity from the cytosol. Translocation of protein kinase C may imply a role for this kinase in contraction-initiated changes in muscle metabolism....

  13. Kinetics of contraction-induced GLUT4 translocation in skeletal muscle fibers from living mice

    DEFF Research Database (Denmark)

    Lauritzen, Hans Peter M. Mortensen; Galbo, Henrik; Toyoda, Taro

    2010-01-01

    Exercise is an important strategy for the treatment of type 2 diabetes. This is due in part to an increase in glucose transport that occurs in the working skeletal muscles. Glucose transport is regulated by GLUT4 translocation in muscle, but the molecular machinery mediating this process is poorly...... understood. The purpose of this study was to 1) use a novel imaging system to elucidate the kinetics of contraction-induced GLUT4 translocation in skeletal muscle and 2) determine the function of AMP-activated protein kinase alpha2 (AMPKalpha2) in this process....

  14. Balanced Chromosomal Translocation of Chromosomes 6 and 7: A Rare Male Factor of Spontaneous Abortions

    Directory of Open Access Journals (Sweden)

    Sefa Resim

    2013-06-01

    Full Text Available Background: Carriers of structural chromosomal rearrangements such as Robertsonian or reciprocal translocations have an increased risk of spontaneous abortion and producing offspring with genetic abnormalities. Case Report: We report a man with balanced chromosomal translocations located at 6p22, and 7q22. His wife has a history of four spontaneous abortions. Conclusion: Couples with a history of abortions should be investigated cytogenetically, after other causes of miscarriages are excluded. The possibility of spontaneous abortions can be reduced with preimplantation genetic diagnosis (PGD before embryo transfer.

  15. 134Cs foliar contamination of vine: translocation to grapes and transfer to wine

    International Nuclear Information System (INIS)

    Carini, F.; Anguissola Scotti, I.; Montruccoli, M.; Silva, S.

    1996-01-01

    Grape vines growing in pots placed in open field were contaminated by sprinkling an aqueous solution of carrier free 134 Cs. Activity was determined in acini and must at the ripening stage. Interception and Translocation Factors (TLF) were quantified. They strictly depend on the state of growth of the crop. Wine was produced by a laboratory process and analysed as to radiocesium. Transfer parameters, F r and P e , were calculated to predict radiocesium concentration in wine: it is 0.6 times the activity found in grapes. The leaf fruit translocation seems to be the dominant process in the contamination of acini when compared to direct deposition. (author)

  16. Bacteremia and bacterial translocation in the naturally occurring canine gastric dilatation-volvulus patient.

    Science.gov (United States)

    Winkler, Kevin P; Greenfield, Cathy L; Schaeffer, David J

    2003-01-01

    This prospective study was performed to determine the prevalence of bacteremia in the naturally occurring gastric dilatation-volvulus (GDV) patient, the possible relationship between bacteremia and survival, and whether bacteremia was a result of translocation from the stomach. Blood cultures were collected from each patient. Bacterial cultures were collected from the liver, mesenteric lymph node, and stomach. Forty-three percent of the GDV cases and 40% of the controls developed positive blood cultures. Gram-negative rods were the most frequently isolated organisms. Evidence of bacterial translocation from the stomach could not be demonstrated in GDV patients, and survival was not affected by the presence of bacteremia.

  17. Effect of dose rate on the translocation yield in rat spermatogonia

    International Nuclear Information System (INIS)

    Vyglenov, A.; Rudnitski, T.; Kokhmanska-Tvardovska, A.

    1987-01-01

    The effectiveness of chronic gamma-irradiation with dose rate 1.10 -4 Gy/min on the yield of reciprocal translocations in rat spermatogonia was studied. Comparsion was made with acute gamma-irradiation at emissive power 1,23 Gy/min. Emissive power decrease by four orders reduced 12 times the extent of genetic injury - from 34,9 down to 3 translocations per cellx10 -5 /cGy. In this respect, the rat is close to the laboratory mouse

  18. Studies on uptake and translocation of some nutrient elements in plant

    International Nuclear Information System (INIS)

    Aly, S.S.M.

    1985-01-01

    The main objective of this work is to study the uptake and translocation of some nutrients. In this respect, two experiments, dealing with 3 2 P and 6 5 Zn, were conducted using a sandy clay loam soil where corn plants were grown to study such influence on the uptake and translocation of P, Zn, N and K.The utilization of P and Zn fertilizers by corn plants as well as the production of dry matter yield were considered. Chemical analysis of some mineral components and assay of radioactive materials 3 2 P and 6 5 Zn of both plant and soil and the dry weight of corn plants were estimated

  19. Escherichia coli morphological changes and lipid A removal induced by reduced pressure nitrogen afterglow exposure.

    Directory of Open Access Journals (Sweden)

    Hayat Zerrouki

    Full Text Available Lipid A is a major hydrophobic component of lipopolysaccharides (endotoxin present in the membrane of most Gram-negative bacteria, and the major responsible for the bioactivity and toxicity of the endotoxin. Previous studies have demonstrated that the late afterglow region of flowing post-discharges at reduced pressure (1-20 Torr can be used for the sterilization of surfaces and of the reusable medical instrumentation. In the present paper, we show that the antibacterial activity of a pure nitrogen afterglow can essentially be attributed to the large concentrations of nitrogen atoms present in the treatment area and not to the UV radiation of the afterglow. In parallel, the time variation of the inactivation efficiency quantified by the log reduction of the initial Escherichia coli (E. coli population is correlated with morphologic changes observed on the bacteria by scanning electron microscopy (SEM for increasing afterglow exposure times. The effect of the afterglow exposure is also studied on pure lipid A and on lipid A extracted from exposed E. coli bacteria. We report that more than 60% of lipid A (pure or bacteria-extracted are lost with the used operating conditions (nitrogen flow QN2 = 1 standard liter per minute (slpm, pressure p = 5 Torr, microwave injected power PMW = 200 W, exposure time: 40 minutes. The afterglow exposure also results in a reduction of the lipid A proinflammatory activity, assessed by the net decrease of the redox-sensitive NFκB transcription factor nuclear translocation in murine aortic endothelial cells stimulated with control vs afterglow-treated (pure and extracted lipid A. Altogether these results point out the ability of reduced pressure nitrogen afterglows to neutralize the cytotoxic components in Gram-negative bacteria.

  20. Atrofia mucosa/translocação bacteriana na sepse experimental em ratos Wistar Mucosal atrophy/bacterial translocation in experimental sepsis in Wistar rats

    Directory of Open Access Journals (Sweden)

    Armando José d'Acampora

    2004-10-01

    Full Text Available OBJETIVO: Avalizar a relação entre lesão mucosa e translocação bacteriana. MÉTODO: Utilizou-se 50 ratos distribuídos em 5 grupos: 1.Controle: injeção de inóculo padrão de Pseudomonas aeruginosa, 2.Dreno: injeção do inóculo padrão e drenagem da cavidade abdominal, após 6 horas, 3.Lavado: injeção do inóculo padrão e lavagem da cavidade abdominal, após 6 horas, 4.Lavado + dreno: injeção do inóculo padrão e após 6 horas, drenagem e lavagem da cavidade, 5.Normal: avaliação histológica da parede intestinal normal. Após o óbito, realizou-se hemocultura e cultura peritoneal. Realizou-se medida da espessura total da parede do jejuno e da camada mucosa em vilosidades seccionadas de forma longitudinal. RESULTADOS: Na hemocultura, houve crescimento de Pseudomonas aeruginosa e Escherichia coli em 90% e 52,5% dos animais. Na cultura peritoneal, houve crescimento de P. aeruginosa, E. coli e Klebsiella sp em 87,5%, 85% e 5% dos animais. Quanto a altura da camada mucosa e da parede intestinal, não houve alteração estatisticamente significativa entre os 5 grupos. CONCLUSÃO: A sepse aguda não causou alteração na camada mucosa do intestino delgado e a translocação ocorrida não pode ser considerada como decorrente de uma lesão da mucosa intestinal.PURPOSE: Observe the relation between small intestine's mucosal injury and bacterial translocation. METHODS: 50 adult female rats were distributed in 5 groups: 1. Control: intraperitoneal injection of Pseudomonas aeruginosa, 2. Drainage: intraperitoneal injection of P. aeruginosa and drainage of the abdominal cavity, after 6 hours, 3. Washed: intraperitoneal injection of P. aeruginosa and washing of the abdominal cavity, after 6 hours, 4. Washed + drainage: intraperitoneal injection of P. aeruginosa plus drainage and washing of the cavity, after 6 hours, 5. Normal: evaluation of the normal intestinal wall. After death, blood and peritoneal cultures were performed. Fragments of

  1. Construindo uma política feminista translocal da tradução Enacting a Translocal Feminist Politics of Translation

    Directory of Open Access Journals (Sweden)

    Sonia E Alvarez

    2009-12-01

    Full Text Available Nosso projeto coletivo Translocalities/Translocalidades: Feminist Politics of Translation in the Latin/a Américas (Políticas Feministas de Tradução na América Latina explora como discursos e práticas feministas viajam por uma variedade de lugares e direções e acabam se tornando paradigmas interpretativos para a leitura/escrita de questões de classe, gênero, sexualidade, migração, saúde, cidadania, política e circulação de identidades e textos. Sustentamos que a tradução é política e teoricamente indispensável para forjar epistemologias e alianças políticas feministas, antirracistas e pós-coloniais/pós-ocidentais, pois as Américas Latinas - enquanto formação cultural transfronteiriça e não territorialmente delimitada - devem ser entendidas como translocais em dois sentidos. O primeiro sentido que usamos - o de translocalidade - parte de movimentos além das concepções da "política da localização" empregadas pelo feminismo terceiro-mundista estadunidense. Mais do que "migrar" e "se assimilar", muitas pessoas nas Américas Latinas cada vez mais se movem de um lado para outro entre localidades, entre lugares historicamente situados e culturalmente específicos, ainda que porosos, atravessando múltiplas fronteiras, e não apenas entre nações (como deixa a entender o termo "migração transnacional", por exemplo. Empregamos a expressão translocal, então, em um segundo sentido, que chamamos de translocalidades, precisamente para capturar esses cruzamentos e movimentos multidirecionaisOur collective project on Translocalities/Translocalidades: Feminist Politics of Translation in the Latin/a Américas explores how feminist discourses and practices travel across a variety of sites and directionalities to become interpretive paradigms to read/write issues of class, gender, race, sexuality, migration, health, social movements, citizenship, politics, and the circulation of identities and texts. Translation is

  2. Translocation of differently sized and charged polystyrene nanoparticles in in vitro intestinal cell models of increasing complexity

    NARCIS (Netherlands)

    Walczak, A.P.; Kramer, E.; Hendriksen, P.J.M.; Tromp, P.; Helsper, J.P.F.G.; Zande, M. van der; Rietjens, I.M.C.M.; Bouwmeester, H.

    2015-01-01

    Intestinal translocation is a key factor for determining bioavailability of nanoparticles (NPs) after oral uptake. Therefore, we evaluated three in vitro intestinal cell models of increasing complexity which might affect the translocation of NPs: a mono-culture (Caco-2 cells), a co-culture with

  3. Robertsonian translocations: An overview of a 30-year experience in a single tertiary medical center in Taiwan

    Directory of Open Access Journals (Sweden)

    Yi-Wen Chang

    2013-06-01

    Conclusion: Although AMA is an indication for amniocentesis in approximately two-fifths of cases with Robertsonian translocations, the indication of parent with abnormal karyotypes was more likely to lead to the detection of non-de novo Robertsonian translocations, suggesting that parents with abnormal karyotypes need careful prenatal consultation.

  4. OK-432 reduces mortality and bacterial translocation in irradiated and granulocyte-colony stimulating factor (G-CSF)-treated mice

    Energy Technology Data Exchange (ETDEWEB)

    Nose, Masako; Uzawa, Akiko; Ogyu, Toshiaki [National Inst. of Radiological Sciences, Chiba (Japan); Suzuki, Gen

    2001-06-01

    Acute radiation induces bacterial translocation from the gut, followed by systemic infection and sepsis. In order to reduce the mortality after acute whole body irradiation, it is essential to control bacterial translocation. In this study, we established a bacterial translocation assay as a sensitive method to detect minor mucosal injury by radiation. By utilizing this assay, we evaluated the adverse effects, if any, of hematopoietic reagents on the mucosal integrity in the respiratory and gastro-intestinal tracts. Bacterial translocation to the liver and spleen occurred after whole-body irradiation if the dose exceeded 6 Gy. The administration of G-CSF unexpectedly increased the bacterial translocation in 8 Gy-irradiated mice. The pharmaceutical preparation of low-virulent Streptococcus pyogenes, OK-432, significantly reduced the endotoxin levels in peripheral blood without any reduction of bacterial translocation. A combined treatment with G-CSF and OK-432 decreased bacterial translocation and prevented death. This result indicates that the early administration of G-CSF has an adverse effect on bacterial translocation, and that a combined treatment of G-CSF and OK-432 attenuates the adverse effect of G-CSF and improves the survival rate after acute irradiation. (author)

  5. Translocations of Chromosome End-Segments and Facultative Heterochromatin Promote Meiotic Ring Formation in Evening Primroses[W][OPEN

    Science.gov (United States)

    Golczyk, Hieronim; Massouh, Amid; Greiner, Stephan

    2014-01-01

    Due to reciprocal chromosomal translocations, many species of Oenothera (evening primrose) form permanent multichromosomal meiotic rings. However, regular bivalent pairing is also observed. Chiasmata are restricted to chromosomal ends, which makes homologous recombination virtually undetectable. Genetic diversity is achieved by changing linkage relations of chromosomes in rings and bivalents via hybridization and reciprocal translocations. Although the structural prerequisite for this system is enigmatic, whole-arm translocations are widely assumed to be the mechanistic driving force. We demonstrate that this prerequisite is genome compartmentation into two epigenetically defined chromatin fractions. The first one facultatively condenses in cycling cells into chromocenters negative both for histone H3 dimethylated at lysine 4 and for C-banding, and forms huge condensed middle chromosome regions on prophase chromosomes. Remarkably, it decondenses in differentiating cells. The second fraction is euchromatin confined to distal chromosome segments, positive for histone H3 lysine 4 dimethylation and for histone H3 lysine 27 trimethylation. The end-segments are deprived of canonical telomeres but capped with constitutive heterochromatin. This genomic organization promotes translocation breakpoints between the two chromatin fractions, thus facilitating exchanges of end-segments. We challenge the whole-arm translocation hypothesis by demonstrating why reciprocal translocations of chromosomal end-segments should strongly promote meiotic rings and evolution toward permanent translocation heterozygosity. Reshuffled end-segments, each possessing a major crossover hot spot, can furthermore explain meiotic compatibility between genomes with different translocation histories. PMID:24681616

  6. Fine mapping of the human renal oncocytoma-associated translocation (5;11)(q35;q13) breakpoint

    NARCIS (Netherlands)

    Sinke, RJ; Dijkhuizen, T; Janssen, B; Weghuis, DO; Merkx, G; vandenBerg, E; Schuuring, E; Meloni, AM; deJong, B; vanKessel, AG

    1997-01-01

    Recent cytogenetic analysis of a series of human renal oncocytomas revealed the presence of a recurring chromosomal translocation (5;11)(q35;q13) as sole anomaly in a subset of the tumors. The molecular characterization of this translocation was initiated using two primary t(5;11)-positive renal

  7. Identification and Prevalence of Escherichia coli and Escherichia coli O157: H7 in Foods

    Directory of Open Access Journals (Sweden)

    Ancuta Mihaela Rotar

    2013-11-01

    Full Text Available The objective of this study is to investigate the incidence of Escherichia coli in animal and non-animal foods, and mainly the incidence of the serotype O157: H7 producing verotoxin. The presence of common Escherichia coli and Escherichia coli O157: H7 in various foods (of animal and non animal origin was performed in Transylvania area. We analyzed a total of one hundred forty-one samples of minced meat, one hundred twenty-six samples of meat , twenty six samples of meat products, five samples of alcoholic beverages, three samples of seafood, one hundred samples of cheese from pasteurized milk, seventeen samples of butter, four samples of vegetables and one sample of milk powder, using the standard cultural method and Vidas Eco method for E. coli O157: H7 strains. E. coli was identified in 50 samples of minced meat, 55 samples of meat prepared, 4 samples of meat products, 2 samples of alcoholic beverages, 25 samples of cheese from pasteurized milk, 6 samples of butter and 1 sample of vegetables. In this study were not been identified any foods contaminated with the E. coli O157: H7 serotype. The results of this reasearch have demostrated that E. coli wich represents a hygienic indicator of recent food contamination, can be destroyed with heat treatment and hygienic handling of foods. Our country over the years has been among the few countries where the incidence of the E. coli O157: H7 serotype has been minimal.

  8. Influence of artificial cavity age on red-cockaded woodpecker translocation success

    Science.gov (United States)

    Daniel Saenz; Richard R. Schaefer; Richard N. Conner; D. Craig Rudolph; Dawn K. Carrie; M. Stephen Best

    2004-01-01

    Red-cockaded woodpecker (Picoides borealis) translocations have been used to bolster woodpecker populations and to fill breeding vacancies. Artificial, insert cavities have been used to offset cavity shortages in woodpecker clusters and are the primary cavity type used in recruitment clusters in Texas and Arkansas, but inserts may lose their...

  9. Comparative Genomics of Interreplichore Translocations in Bacteria: A Measure of Chromosome Topology?

    Science.gov (United States)

    Khedkar, Supriya; Seshasayee, Aswin Sai Narain

    2016-06-01

    Genomes evolve not only in base sequence but also in terms of their architecture, defined by gene organization and chromosome topology. Whereas genome sequence data inform us about the changes in base sequences for a large variety of organisms, the study of chromosome topology is restricted to a few model organisms studied using microscopy and chromosome conformation capture techniques. Here, we exploit whole genome sequence data to study the link between gene organization and chromosome topology in bacteria. Using comparative genomics across ∼250 pairs of closely related bacteria we show that: (a) many organisms show a high degree of interreplichore translocations throughout the chromosome and not limited to the inversion-prone terminus (ter) or the origin of replication (oriC); (b) translocation maps may reflect chromosome topologies; and (c) symmetric interreplichore translocations do not disrupt the distance of a gene from oriC or affect gene expression states or strand biases in gene densities. In summary, we suggest that translocation maps might be a first line in defining a gross chromosome topology given a pair of closely related genome sequences. Copyright © 2016 Khedkar and Seshasayee.

  10. Translocation 1;7 in dyshematopoiesis: possibly induced with a nonrandom geographic distribution

    International Nuclear Information System (INIS)

    Scheres, J.M.; Hustinx, T.W.; Holdrinet, R.S.; Geraedts, J.P.; Hagemeijer, A.; van der Blij-Philipsen, M.

    1984-01-01

    Eight patients with various hematologic disorders had an identical chromosomal aberration in their bone marrow or unstimulated peripheral blood, a translocation t(1;7) interpreted as t(1;7)(p11;p11). The translocation chromosome replaced one normal chromosome number7; therefore, the karyotype of the abnormal cells was trisomic for 1q and monosomic for 7q. Including four cases from the literature, a total of 12 patients (4 women, 8 men) with this translocation are known at the moment. The translocation does not seem to be associated with a specific disorder, but almost all patients had a preleukemic syndrome during some stage of their disease. It is very remarkable that 11 of the 12 patients lived in the Netherlands, and 7 patients had a history of iatrogenic exposure to alkylating agents or irradiation; one patient was a radiation worker and another one had a history of toxic exposure to chloramphenicol. It is suggested, therefore, that the t(1;7) is a possibly induced chromosomal aberration with a clearly nonrandom geographic distribution

  11. Sequence-Based Analysis of Translocations and Inversions in Bread Wheat (Triticum aestivum L.)

    Czech Academy of Sciences Publication Activity Database

    Ma, J.; Stiller, J.; Berkman, P.J.; Wei, Y.M.; Rogers, J.; Feuillet, C.; Doležel, Jaroslav; Mayer, K. F.; Eversole, K.; Zheng, Y.L.; Liu, C.L.

    2013-01-01

    Roč. 8, č. 11 (2013) E-ISSN 1932-6203 Institutional research plan: CEZ:AV0Z50380511 Keywords : CHROMOSOMAL TRANSLOCATIONS * HOMOEOLOGOUS GROUP-4 * EVOLUTION Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.534, year: 2013

  12. (q24: q12) translocation is common in Ewing's sarcoma/peripheral ...

    Indian Academy of Sciences (India)

    The Ewing's sarcoma family can present diagnostic difficulties. In the past the basis of diagnosis has been a exclusion. Identification of a specific translocation especially t(11; 22) (EWS-FLI 1 fusion gene), which is seen in nearly 85% of Ewing's sarcoma cases can help in precise diagnosis. We have carried out a study on ...

  13. Translocation success of Frithia humilis Burgoyne, an endangered succulent plant: preliminary results

    Directory of Open Access Journals (Sweden)

    E. Kruger

    2012-03-01

    Full Text Available AFrithia humilispopulation,growing on a licensed mining plot nearWitbank was saved from obliteration in 2009. It was translocated to three habitats, which havebeen monitored since 2010. Thus far, flowering has increased despite decreasing populationnumbers; the populations seem stable.

  14. Translocation studies in Loranthus (dendrophthoe falcata (L.F) using labelled 14C

    International Nuclear Information System (INIS)

    Girija, T.; Suresh Kumar, P.; Francis, Vidhu; Abraham, C.T.

    2006-01-01

    Radioisotope studies with 14 C indicated that 4.07 per cent of the CO 2 fixed by loranthus leaves was translocated to the nearest cocoa leaf by the second day. This revealed that there is movement of prepared nutrients from the parasite to the host. The study also revealed that systemic herbicides cannot be safely recommended for the control of loranthus. (author)

  15. Mobilizing Learning Resources in a Transnational Classroom: Translocal and Digital Resources in a Community Technology Center

    Science.gov (United States)

    Noguerón-Liu, Silvia

    2014-01-01

    Drawing from transnational and activity theory frameworks, this study analyzes the ways translocal flows shape learning in a community technology center serving adult immigrants in the US Southwest. It also explores students' constructions of the transnational nature of the courses they took, where they had access to both online and face-to-face…

  16. Laboratory evaluation of interception and translocation of 131I in fenugreek and Okra plants

    International Nuclear Information System (INIS)

    Singhal, R.K.; Narayanan, U.; Bhat, I.S.

    1994-01-01

    The work reported here deals with the study of interception and translocation of airborne 131 I in fenugreek (Trigonella foenum-graecum) and okra (Hibiscus esculentus), two very common vegetables in India. Activity was injected into the experimental chamber in the form of iodide aerosols having a size distribution of 0.3 to 5.0 μm (AMAD). Samples of plants were collected over a period of a few days at different time intervals after injection of the aerosols. Evaluation of interception with deposition and translocation of 131 I was done from the activity measured in air and in plant parts. For the deposition factor, the values are 1.22 m 3 kg -1 for fenugreek leaves, and 1.49 m 3 kg -1 for the plant as a whole. For okra plants these values are 0.02 and 0.16 m 3 kg -1 in edible okra and leaves, respectively. For the okra plant as a whole, the value is 0.19 m 3 kg -1 . The translocation factors vary from 0.62 to 0.86 and 0.47 to 0.87 for leaves and stem, respectively, in the case of fenugreek plants. For okra plants, the translocation factor varies from 0.21 to 0.82, 0.53 to 0.93, and 0.42 to 0.81 in edible okra, leaves, and stems, respectively. 13 refs., 6 figs., 2 tabs

  17. Four centuries of translocal development in cities and regions in Northwest Germany

    NARCIS (Netherlands)

    Terlouw, K.

    2013-01-01

    This paper analyses how the fates of different peripheral localities (Emsland, Gütersloh, and Lippe in Germany) were linked to the outside world in the course of the seventeenth to twentieth centuries. In the first centuries, these localities' translocal relations with the world economy were

  18. XP11.2 Translocation renal cell carcinoma: Clinical experience of Taipei Veterans General Hospital

    Directory of Open Access Journals (Sweden)

    Chia-Chen Hung

    2011-11-01

    Conclusion: Although RT-PCR and DNA sequencing are the final diagnoses of the molecular identity of Xp11.2 translocation RCC, experienced pathologists could confirm the histologic diagnosis based on the distinctive morphologic features with positive TFE3 immunochemical nuclear stain. Surgical resection is the only treatment. The role of systemic therapy for local recurrence and metastasis remains to be determined.

  19. Literacy as a Translocal Practice: Digital Multimodal Literacy Practices among Girls Resettled as Refugees

    Science.gov (United States)

    Omerbašic, Delila

    2015-01-01

    Situated in critical sociocultural theory of literacy with a particular focus on literacy in relation to space and displacement, this qualitative study considers how nine teenage girls who were resettled as refugees from Thailand engage in productions of translocality through multimodal literacy practices in digital spaces. The girls are…

  20. Comparative Genomics of Interreplichore Translocations in Bacteria: A Measure of Chromosome Topology?

    Directory of Open Access Journals (Sweden)

    Supriya Khedkar

    2016-06-01

    Full Text Available Genomes evolve not only in base sequence but also in terms of their architecture, defined by gene organization and chromosome topology. Whereas genome sequence data inform us about the changes in base sequences for a large variety of organisms, the study of chromosome topology is restricted to a few model organisms studied using microscopy and chromosome conformation capture techniques. Here, we exploit whole genome sequence data to study the link between gene organization and chromosome topology in bacteria. Using comparative genomics across ∼250 pairs of closely related bacteria we show that: (a many organisms show a high degree of interreplichore translocations throughout the chromosome and not limited to the inversion-prone terminus (ter or the origin of replication (oriC; (b translocation maps may reflect chromosome topologies; and (c symmetric interreplichore translocations do not disrupt the distance of a gene from oriC or affect gene expression states or strand biases in gene densities. In summary, we suggest that translocation maps might be a first line in defining a gross chromosome topology given a pair of closely related genome sequences.

  1. A New Noncanonical Anionic Peptide That Translocates a Cellular Blood–Brain Barrier Model

    Directory of Open Access Journals (Sweden)

    Sara Neves-Coelho

    2017-10-01

    Full Text Available The capacity to transport therapeutic molecules across the blood–brain barrier (BBB represents a breakthrough in the development of tools for the treatment of many central nervous system (CNS-associated diseases. The BBB, while being protective against infectious agents, hinders the brain uptake of many drugs. Hence, finding safe shuttles able to overcome the BBB is of utmost importance. Herein, we identify a new BBB-translocating peptide with unique properties. For years it was thought that cationic sequences were mandatory for a cell-penetrating peptide (CPP to achieve cellular internalization. Despite being anionic at physiological pH, PepNeg (sequence (SGTQEEY is an efficient BBB translocator that is able to carry a large cargo (27 kDa, while maintaining BBB integrity. In addition, PepNeg is able to use two distinct methods of translocation, energy-dependent and -independent, suggesting that direct penetration might occur when low concentrations of peptide are presented to cells. The discovery of this new anionic trans-BBB peptide allows the development of new delivery systems to the CNS and contributes to the need to rethink the role of electrostatic attraction in BBB-translocation.

  2. Robertsonian translocation 13/14 associated with rRNA genes ...

    African Journals Online (AJOL)

    Alexander A. Dolskiy

    2017-12-01

    Dec 1, 2017 ... Results: We describe a family case of a translocation rob (13; 14) and elevated rRNA expression in the proband with ..... Clin Genet 2010;78:299–309. ... [9] Bertini V, Fogli A, Bruno R, Azzarà A, Michelucci A, Mattina T, et al.

  3. The effect of acetylcholine on 14C-assimilates translocation of Isatis tinctoria L

    International Nuclear Information System (INIS)

    Yang Chongjun; Tang Feiyu; Zhang Ping; Guo Yuhai

    2004-01-01

    The effects of acetylcholine on 14 C-assimilates translocation are studied with source-channel-sink of Isatis tinctoria L. The experiments show that 0.01 mmol/L treatments of acetylcholine on the phloem, can improve the output of 14 C-assimilates in leaves indicating that acetylcholine enhances the activity of phloem transport. (authors)

  4. Structural differences in reciprocal translocations. Potential for a model of risk in Rcp.

    Science.gov (United States)

    Daniel, A

    1979-10-01

    Interchange segment sizes and the sizes of chromosome imbalance arising from the different modes of meiotic segregation were measured in a selected sample of 20 reciprocal translocations (Rep). The Rep were selected by two modes of ascertainment: (I) neonates with an unbalanced form of the translocation, and (II) couples with recurrent spontaneous abortions without evidence of full-term translocation aneuploid offspring. The measurements (% of haploid autosomal length: %HAL) were plotted as the observed or potential chromosomal imbalance with monosomy (abscissa) and trisomy (ordinate). It was found that (a) the interchange segments were larger in the spontaneous abortion Rcp, (b) that all of the imbalances observed in full-term neonates plotted close to the origin and to the left of the line joining 4% trisomy to 2% monosomy, and (c) the imbalances observed in the neonates in each individual Rcp were of the smallest size possible arising by any segregation mode. It was concluded that a major factor in the survival to term of aneuploid conceptuses is the size (proportion of genome) of the chromosome abnormality, irrespective of the origin of the chromosome regions. These results are discussed in relation to their use as a model to evaluate the risk of abnormal offspring in the progeny of translocation heterozygotes (the Chromosome Imbalance Size-Viability Model).

  5. The efficacy of translocating little penguins Eudyptula minor during an oil spill

    International Nuclear Information System (INIS)

    Hull, Cindy L.; Hindell, Mark A.; Moyle, Diane I.; Gales, Rosemary P.; Brothers, Nigel P.; Meggs, Ross A.

    1998-01-01

    As a consequence of the ship The Iron Baron running aground at Low Head in northern Tasmania, Australia, an unknown number of little penguins Eudyptula minor were contaminated with bunker fuel oil. Of these, 1894 were brought into captivity and cleaned of oil. The area was still contaminated with oil when the penguins were ready for release and, rather than prolong captivity with its associated risk of disease and stress at a time when breeding was imminent, a translocation strategy was trialled, the results of which are reported here. Twenty-five penguins equipped with VHF transmitters were translocated 360 km to the east coast of Tasmania, and their movements tracked from the air. Two birds returned to the capture site in 3 days, insufficient time for clean-up to be completed, prompting a new release site 120 km further south. A further six penguins were tracked at nearby Ninth Island to monitor foraging behaviour. Fifty-six per cent of the birds released at the translocation sites returned to Low Head in 4 months. This is a conservative estimate, and subsequent monitoring found no differences in the survival rate of translocated and control birds. (author)

  6. Intestinal ischemia-reperfusion injury augments intestinal mucosal injury and bacterial translocation in jaundiced rats.

    Science.gov (United States)

    Yüksek, Yunus Nadi; Kologlu, Murat; Daglar, Gül; Doganay, Mutlu; Dolapci, Istar; Bilgihan, Ayse; Dolapçi, Mete; Kama, Nuri Aydin

    2004-01-01

    The aim of this study was to evaluate local effects and degree of bacterial translocation related with intestinal ischemia-reperfusion injury in a rat obstructive jaundice model. Thirty adult Sprague-Dawley rats (200-250 g) were divided into three groups; including Group 1 (jaundice group), Group 2 (jaundice-ischemia group) and Group 3 (ischemia group). All rats had 2 laparotomies. After experimental interventions, tissue samples for translocation; liver and ileum samples for histopathological examination, 25 cm of small intestine for mucosal myeloperoxidase and malondialdehyde levels and blood samples for biochemical analysis were obtained. Jaundiced rats had increased liver enzyme levels and total and direct bilirubin levels (p<0.05). Intestinal mucosal myeloperoxidase and malondialdehyde levels were found to be high in intestinal ischemia-reperfusion groups (p<0.05). Intestinal mucosal damage was more severe in rats with intestinal ischemia-reperfusion after bile duct ligation (p<0.05). Degree of bacterial translocation was also found to be significantly high in these rats (p<0.05). Intestinal mucosa is disturbed more severely in obstructive jaundice with the development of ischemia and reperfusion. Development of intestinal ischemia-reperfusion in obstructive jaundice increases bacterial translocation.

  7. Genetic markers, translocations and sexing genes on chromosome 2 of Ceratitis capitata

    International Nuclear Information System (INIS)

    Cladera, J.L.

    1997-01-01

    A review is presented of results obtained in a search for genetic markers, translocations and selectable genes obtained at the Instituto de Genetica, Castelar, Argentina, with special reference to chromosome 2 linked mutations and genes useful for developing self-sexing strains in Ceratitis capitata. (author)

  8. "Translocal Express" tembutab jälle / Rael Artel, Airi Triisberg

    Index Scriptorium Estoniae

    Artel, Rael, 1980-

    2008-01-01

    Korraldajad 22. ja 23. II Okupatsioonide Muuseumis toimuvast rahvusvahelisest seminarist "Translocal Express. Jubilee Edition", kus vaatluse all on kaasaegse kunsti ja natsionalismi suhted. Seminari kava. Eesti kunstnikest esineb Flo Kasearu, esitletakse Rael Arteli ja Airi Triisbergi raamatut "Public Preparation - Biennale of Young Artists"

  9. Designing Species Translocation Strategies When Populaton Growth and Future Funding Are Uncertain

    Science.gov (United States)

    Robert G. Haight; Katherine Ralls; Anthony M. Starfield

    2000-01-01

    When translocating individuals to found new populations, managers must allocate limited funds among release and monitoring activities that differ in method, cost, and probable result. In addition, managers are increasingly expected to justify the funding decisions they have made. Within the framework of decision analysis, we used robust optimization to formulate and...

  10. Research methods in weed science: herbicide absorption and translocation in plants using radioisotopes

    Science.gov (United States)

    Herbicide absorption and translocation in plants is a key component in the study of herbicide physiology, mode of action, selectivity, resistance mechanisms, and in the registration process. Radioactive herbicides have been in use for over half-a-century in the research and study of herbicide absorp...

  11. Systemic translocation and metabolism of 14C-metalaxyl in citrus

    International Nuclear Information System (INIS)

    Musumeci, M.R.; Ruegg, E.F.

    1984-01-01

    Systemic uptake and translocation of 14 C-metalaxyl to citrus seedlings from soils (Humic Gley and Yellow Red Latosol) with different physical - chemical properties are studied. Seedlings of Citrus limonia are treated with 14 C-metalaxyl. (M.A.C.) [pt

  12. Stabilization, not polymerization, of microtubules inhibits the nuclear translocation of STATs in adipocytes

    International Nuclear Information System (INIS)

    Gleason, Evanna L.; Hogan, Jessica C.; Stephens, Jacqueline M.

    2004-01-01

    Signal transducers and activators of transcriptions (STATs) are a family of latent transcription factors which are activated by a variety of growth factors and cytokines in many cell types. However, the mechanism by which these transcription factors translocate to the nucleus is poorly understood. The goal of this study was to determine the requirement of microfilaments and microtubules for cytokine induced STAT activation in cultured adipocytes. We used seven different actin-specific and microtubule-specific agents that are well-established effectors of these cytoskeletal networks. Our results clearly demonstrate that inhibition of microfilaments or the prevention of microtubule polymerization has no effect on the ability of STATs to be tyrosine phosphorylated or to translocate to the nucleus. However, we observed that paclitaxel, a microtubule stabilizer, resulted in a significant decrease in the nuclear translocation of STATs without affecting the cytosolic tyrosine phosphorylation of these transcription factors. In summary, our results demonstrate that the dynamic instability, but not the polymerization, of microtubules contributes to nuclear translocation of STAT proteins in adipocytes

  13. Translocation of autogenous bone particles to improve peri-implant osteogenesis.

    NARCIS (Netherlands)

    Tabassum, A.; Walboomers, X.F.; Meijer, G.J.; Jansen, J.B.M.J.

    2012-01-01

    During the placement of titanium implants into bone, particles are loosened and translocated as a result of the inherent roughness of the surface. Such bone particles have been shown to play a significant role in new bone formation. Therefore, the aim of the present study was to establish a new

  14. Interception and translocation of radionuclides in major food crops for Koreans

    International Nuclear Information System (INIS)

    Choi, Y. H.; Lim, K. M.; Park, H. G.; Choi, H. J.; Lee, H. S.

    2002-01-01

    In order to investigate the direct plant contamination pathway of 54 Mn, 57 Co, 85 Sr, 103 Ru and 134 Cs in major food crops for Koreans, rice, soybean and radish plants at different growth stages were sprayed with radioactive solutions in a greenhouse. The interception factor and the translocation factor were quantified as the fraction of the total deposition that is initially retained on the aboveground plant surface and the fraction of the total initial plant activity that is contained in the edible part at harvest, respectively. In rice and radish, interception factors increased as plants grew old to harvest. In soybean, however, rapid defoliation in old plants made interception factors decrease with increasing age during the later part of the growth. There was little difference in the interception factor among radionuclides. Translocation factors decreased in the order of 134 Cs ≥> 57 Co > 54 Mn ≥ 85 Sr > 103 Ru in general and varied with radionuclides by factors of 6-4000, depending on application time and plant species. Translocation factors for rice seeds were the highest when radionuclides were applied at the active seed growth stage and those for soybean seeds were the highest following the application at the early pod-filling stage except for 103 Ru. For radish roots, translocation factors were on the whole the highest following the early- growth-stage application. The obtained data can be used for parameter values in food-chain dose assessment models especially for Koreans and many other Asian people

  15. Development and viability of a translocated beaver Castor fiber population in the Netherlands

    NARCIS (Netherlands)

    Nolet, B.A.; Baveco, J.M.

    1996-01-01

    We monitored survival, reproduction and emigration of a translocated beaver Castor fiber population in the Netherlands for five years and used a stochastic model to assess its viability. Between 1988 and 1991, 42 beavers were released in the Biesbosch National Park. The mortality was initially high

  16. Alien and translocated aquatic animals in Southern Africa: a general introduction, checklist and bibliography

    CSIR Research Space (South Africa)

    Bruton, MN

    1985-01-01

    Full Text Available A list of references to research and records of alien and translocated aquatic animals in southern Africa is given, as well as a general introduction to the problem of invasive aquatic animals. Reference is made to 5&7 publications. The genera...

  17. In-vitro photo-translocation of antiretroviral drug delivery into TZMbl cells

    CSIR Research Space (South Africa)

    Malabi, Rudzani

    2017-01-01

    Full Text Available The objectives of this study are to use femtosecond laser pulses in a photo-translocation system to deliver ARVs into HIV infected TZMbl cells, and to investigate the influence of ARVs and laser on cellular processes using different molecular...

  18. Driven translocation of Polymer through a nanopore: effect of heterogeneous flexibility

    Science.gov (United States)

    Adhikari, Ramesh; Bhattacharya, Aniket

    2014-03-01

    We have studied translocation of a model bead-spring polymer through a nanopore whose building blocks consist of alternate stiff and flexible segments and variable elastic bond potentials. For the case of uniform spring potential translocation of a symmetric periodic stiff-flexible chain of contour length N and segment length m (mod(N,2m)=0), we find that the end-to-end distance and the mean first passage time (MFPT) have weak dependence on the length m. The characteristic periodic pattern of the waiting time distribution captures the stiff and flexible segments of the chain with stiff segments taking longer time to translocate. But when we vary both the elastic bond energy, and the bending energy, as well as the length of stiff/flexible segments, we discover novel patterns in the waiting time distribution which brings out structural information of the building blocks of the translocating chain. Partially supported by UCF Office of Research and Commercialization & College of Science SEED grant.

  19. LACE1 interacts with p53 and mediates its mitochondrial translocation and apoptosis

    Czech Academy of Sciences Publication Activity Database

    Česneková, J.; Spáčilová, J.; Hansíková, H.; Houštěk, Josef; Zeman, J.; Stibůrek, L.

    2016-01-01

    Roč. 7, č. 30 (2016), s. 47687-47698 ISSN 1949-2553 R&D Projects: GA ČR(CZ) GA13-07223S Institutional support: RVO:67985823 Keywords : p53 * LACE1 * mitochondria * apoptosis * translocation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.168, year: 2016

  20. Premodern Translocals: German Merchant Diaspora Between Kalmar and Northern German Towns(1250 – 1500)

    DEFF Research Database (Denmark)

    Naum, Magdalena

    2013-01-01

    of diaspora. This case study also illustrates the importance of engagement with the material world for maintaining such dual relationships and prompts general exploration of theimportance of material culture in diasporic and translocal lives. It discusses how things are used to fill the spaces of physical...

  1. High dietary niacin intake is associated with decreased chromosome translocation frequency in airline pilots.

    Science.gov (United States)

    Yong, Lee C; Petersen, Martin R

    2011-02-01

    Experimental studies suggest that B vitamins such as niacin, folate, riboflavin, vitamin B6 and vitamin B12 may protect against DNA damage induced by ionising radiation (IR). However, to date, data from IR-exposed human populations are not available. We examined the intakes of these B vitamins and their food sources in relation to the frequency of chromosome translocations as a biomarker of cumulative DNA damage, in eighty-two male airline pilots. Dietary intakes were estimated by using a self-administered semi-quantitative FFQ. Translocations in peripheral blood lymphocytes were scored by using fluorescence in situ hybridisation whole-chromosome painting. Negative binomial regression was used to estimate rate ratios and 95 % CI, adjusted for age and occupational and lifestyle factors. We observed a significant inverse association between translocation frequency and dietary intake of niacin (P = 0·02): adjusted rate ratio for subjects in the highest tertile compared with the lowest tertile was 0·58 (95 % CI 0·40, 0·83). Translocation frequency was not associated with total niacin intake from food and supplements as well as dietary or total intake of folate, riboflavin or vitamin B6 or B12. However, the adjusted rate ratios were significant for subjects with ≥ median compared with food or a diet high in whole grains but low in red and processed meat may protect against cumulative DNA damage in IR-exposed persons.

  2. Assessing the ability of Salmonella enterica to translocate Type III effectors into plant cells

    Science.gov (United States)

    Salmonella enterica, a human enteric pathogen, has the ability to multiply and survive endophytically in plants, and mutations in genes encoding the type III secretion system (T3SS) or its effectors (T3Es) may contribute to this colonization. Two reporter plasmids for T3E translocation into plant ce...

  3. Langevin dynamics simulation on the translocation of polymer through α-hemolysin pore

    International Nuclear Information System (INIS)

    Sun, Li-Zhen; Luo, Meng-Bo

    2014-01-01

    The forced translocation of a polymer through an α-hemolysin pore under an electrical field is studied using a Langevin dynamics simulation. The α-hemolysin pore is modelled as a connection of a spherical vestibule and a cylindrical β-barrel and polymer-pore attraction is taken into account. The results show that polymer-pore attraction can help the polymer enter the vestibule and the β-barrel as well; however, a strong attraction will slow down the translocation of the polymer through the β-barrel. The mean translocation time for the polymer to thread through the β-barrel increases linearly with the polymer length. By comparing our results with that of a simple pore without a vestibule, we find that the vestibule helps the polymer enter and thread through the β-barrel. Moreover, we find that it is easier for the polymer to thread through the β-barrel if the polymer is located closer to the surface of the vestibule. Some simulation results are explained qualitatively by theoretically analyzing the free-energy landscape of polymer translocation. (paper)

  4. A Hands-On Approach to Teaching Protein Translation & Translocation into the ER

    Science.gov (United States)

    LaBonte, Michelle L.

    2013-01-01

    The process of protein translation and translocation into the endoplasmic reticulum (ER) can often be challenging for introductory college biology students to visualize. To help them understand how proteins become oriented in the ER membrane, I developed a hands-on activity in which students use Play-Doh to simulate the process of protein…

  5. Sustainable Development Mechanism of Food Culture’s Translocal Production Based on Authenticity

    Directory of Open Access Journals (Sweden)

    Guojun Zeng

    2014-10-01

    Full Text Available Food culture is a kind of non-material culture with authenticity. To achieve sustainable development of translocal heritage and food culture, we must protect its authenticity. By selecting the cases of the Dongbeiren Flavor Dumpling Restaurant and the Daozanjia Northeast Dumpling Restaurant and using the in-depth interview method, this study discusses how northeastern Cuisine in Guangzhou balances the inheritance and innovation of authenticity, how producers and customers negotiate, and how to realize sustainable development. The main conclusions are: first, there are two different paths of translocal food culture production, which are “authentic food culture production” and “differentiated food culture production”. Second, what translocal enterprises produce is not objective authenticity, but constructive authenticity, or even existential authenticity. Third, compared with differentiated food culture production, authentic food culture production is helpful for the sustainable development of local food culture production. It protects the locality while transmitting and developing the local culture. Fourth, translocal food culture production is a process in which the producers and consumers continue to interact to maintain a state of equilibrium, which informs the sustainable development mechanism with a high degree of authenticity.

  6. The asymptomatic bacteriuria Escherichia coli strain 83972 outcompetes uropathogenic E. coli strains in human urine

    DEFF Research Database (Denmark)

    Hancock, Viktoria; Ulett, G.C.; Schembri, M.A.

    2006-01-01

    Escherichia coli is the most common organism associated with asymptomatic bacteriuria (ABU). In contrast to uropathogenic E. coli (UPEC), which causes symptomatic urinary tract infections (UTI), very little is known about the mechanisms by which these strains colonize the human urinary tract....... The prototype ABU E. coli strain 83972 was originally isolated from a girl who had carried it asymptomatically for 3 years. Deliberate colonization of UTI-susceptible individuals with E. coli 83972 has been used successfully as an alternative approach for the treatment of patients who are refractory...... to conventional therapy. Colonization with strain 83972 appears to prevent infection with UPEC strains in such patients despite the fact that this strain is unable to express the primary adhesins involved in UTI, viz. P and type 1 fimbriae. Here we investigated the growth characteristics of E. coli 83972 in human...

  7. hPEPT1 Affinity and Translocation of Selected Gln-Sar and Glu-Sar Dipeptide Derivatives

    DEFF Research Database (Denmark)

    Eriksson, A. H.; Elm, Peter L.; Begtrup, Mikael

    2005-01-01

    using 14C-labeled Gly-Sar. Translocation was measured as fluorescence ratios induced by the substrates using the fluorescent probe BCECF and an epifluorescence microscope setup. All compounds showed high affinity to hPEPT1, but only the amides l-Gln(N,N-dimethyl)-Sar and l-Gln(N-piperidinyl)-Sar were...... been suggested. However, these are not necessarily predictive of compounds that are actually translocated by hPEPT1. More information on affinity to and translocation via hPEPT1 of side-chain-modified dipeptides may be gained by conducting a study of selected dipeptide derivatives with variety in size...... translocated by hPEPT1. hPEPT1 is very susceptible to modifications of the N-terminal amino acid side chain of dipeptidomimetic substrates, in terms of achieving compounds with high affinity for the transporter. However, as affinity is not predictive of translocation, derivatization in this position must...

  8. Translocation of 14C-photosynthates under normal and moisture stress conditions in finger millet (Eleusine coracana) gaertin

    International Nuclear Information System (INIS)

    Udayakumar, M.; Rama Rao, S.; Krishna Sastry, K.S.

    1981-01-01

    Translocation of photosynthates into different sinks was studied following feeding a single leaf with 14 CO 2 in 40 day old stressed and non-stressed plants of Eleusine coracana. The rate of efflux of 14 C-photosynthates was twice as much in non-stressed plants compared to stressed plants. Young developing leaves, stem apex and stem which are the potential sinks under non-stressed conditions received very little activity under stress conditions. Percent activity in the roots was enhanced under stress suggesting the pattern of translocation was altered under stress conditions. In the plants subjected to moisture stress, after feeding with 14 CO 2 the rate of efflux of 14 C-photosynthates from the fed leaf decreased and the pattern of translocation was altered. Though the effect of stress seems to be directly on the translocation system, the photosynthetic rate appears to be more sensitive to stress than translocation. (author)

  9. A cohort of balanced reciprocal translocations associated with dyslexia: identification of two putative candidate genes at DYX1

    DEFF Research Database (Denmark)

    Buonincontri, Roberta; Bache, Iben; Silahtaroglu, Asli

    2011-01-01

    Dyslexia is one of the most common neurodevelopmental disorders where likely many genes are involved in the pathogenesis. So far six candidate dyslexia genes have been proposed, and two of these were identified by rare chromosomal translocations in affected individuals. By systematic re......-examination of all translocation carriers in Denmark, we have identified 16 different translocations associated with dyslexia. In four families, where the translocation co-segregated with the phenotype, one of the breakpoints concurred (at the cytogenetic level) with either a known dyslexia linkage region--at 15q21...... (DYX1), 2p13 (DYX3) and 1p36 (DYX8)--or an unpublished linkage region at 19q13. As a first exploitation of this unique cohort, we identify three novel candidate dyslexia genes, ZNF280D and TCF12 at 15q21, and PDE7B at 6q23.3, by molecular mapping of the familial translocation with the 15q21 breakpoint....

  10. Energetics of Ortho-7 (oxime drug translocation through the active-site gorge of tabun conjugated acetylcholinesterase.

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    Vivek Sinha

    Full Text Available Oxime drugs translocate through the 20 Å active-site gorge of acetylcholinesterase in order to liberate the enzyme from organophosphorus compounds' (such as tabun conjugation. Here we report bidirectional steered molecular dynamics simulations of oxime drug (Ortho-7 translocation through the gorge of tabun intoxicated enzyme, in which time dependent external forces accelerate the translocation event. The simulations reveal the participation of drug-enzyme hydrogen bonding, hydrophobic interactions and water bridges between them. Employing nonequilibrium theorems that recovers the free energy from irreversible work done, we reconstruct potential of mean force along the translocation pathway such that the desired quantity represents an unperturbed system. The potential locates the binding sites and barriers for the drug to translocate inside the gorge. Configurational entropic contribution of the protein-drug binding entity and the role of solvent translational mobility in the binding energetics is further assessed.

  11. Melanotic MiT family translocation neoplasms: Expanding the clinical and molecular spectrum of this unique entity of tumors.

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    Saleeb, Rola M; Srigley, John R; Sweet, Joan; Doucet, Cedric; Royal, Virginie; Chen, Ying-Bei; Brimo, Fadi; Evans, Andrew

    2017-11-01

    MiT family translocation tumors are a group of neoplasms characterized by translocations involving MiT family transcription factors. The translocation renal cell carcinomas, TFE3 (Xp11.2) and TFEB (t6;11) are known members of this family. Melanotic Xp11 translocation renal cancer is a more recently described entity. To date only 14 cases have been described. It is characterized by a distinct set of features including a nested epithelioid morphology, melanin pigmentation, labeling for markers of melanocytic differentiation, lack of labeling for markers of renal tubular differentiation, predominance in a younger age population and association with aggressive clinical behavior. There are noted similarities between that entity and TFE3 associated PEComas. There are no cases reported of equivalent melanotic TFEB translocation renal cancer. We report 2 rare cases of melanotic translocation renal neoplasms. The first is a melanotic TFE3 translocation renal cancer with an indolent clinical course, occurring in a patient more than 3-decades older than the usual average age in which such tumors have been described. The other case is, to our knowledge, the first reported melanotic TFEB translocation cancer of the kidney. Both cases exhibit the same H&E morphology as previously reported in melanotic translocation renal cancers and label accordingly with HMB45 and Melan-A. While the TFE3 melanotic tumor lacked any evidence of renal tubular differentiation, the TFEB melanotic cancer exhibited some staining for renal tubular markers. Based on the unique features noted above, these two cases expand the clinical and molecular spectrum of the melanotic translocation renal cancers. Copyright © 2017 Elsevier GmbH. All rights reserved.

  12. Simultaneous localization of MLL, AF4 and ENL genes in interphase nuclei by 3D-FISH: MLL translocation revisited

    International Nuclear Information System (INIS)

    Gué, Michaël; Sun, Jian-Sheng; Boudier, Thomas

    2006-01-01

    Haematological cancer is characterised by chromosomal translocation (e.g. MLL translocation in acute leukaemia) and two models have been proposed to explain the origins of recurrent reciprocal translocation. The first, established from pairs of translocated genes (such as BCR and ABL), considers the spatial proximity of loci in interphase nuclei (static 'contact first' model). The second model is based on the dynamics of double strand break ends during repair processes (dynamic 'breakage first' model). Since the MLL gene involved in 11q23 translocation has more than 40 partners, the study of the relative positions of the MLL gene with both the most frequent partner gene (AF4) and a less frequent partner gene (ENL), should elucidate the MLL translocation mechanism. Using triple labeling 3D FISH experiments, we have determined the relative positions of MLL, AF4 and ENL genes, in two lymphoblastic and two myeloid human cell lines. In all cell lines, the ENL gene is significantly closer to the MLL gene than the AF4 gene (with P value < 0.0001). According to the static 'contact first' model of the translocation mechanism, a minimal distance between loci would indicate a greater probability of the occurrence of t(11;19)(q23;p13.3) compared to t(4;11)(q21;q23). However this is in contradiction to the epidemiology of 11q23 translocation. The simultaneous multi-probe hybridization in 3D-FISH is a new approach in addressing the correlation between spatial proximity and occurrence of translocation. Our observations are not consistent with the static 'contact first' model of translocation. The recently proposed dynamic 'breakage first' model offers an attractive alternative explanation

  13. HELICOBACTER PYLORI AND t(11;18(q21;q21 TRANSLOCATION IN GASTRIC MALT LYMPHOMA

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    Karine Sampaio LIMA

    2014-04-01

    Full Text Available Context Gastric mucosa-associated lymphoid tissue (MALT lymphoma is clearly associated with Helicobacter pylori gastritis and can be cured with anti- H pylori therapy alone. The presence of t(11;18(q21;q21 translocation is thought to predict a lower response rate to anti- H pylori treatment. Objectives To study the presence of t(11;18(q21;q21 genetic translocation and its clinical impact in low-grade gastric MALT lymphoma Brazilian patients. Methods A consecutive series of eight patients with gastric MALT lymphoma were submitted to gastroscopy, endoscopic ultrasound, histopathological examination, H pylori search and RT-PCR-based methodology. All patients received anti-H pylori treatment. Eradicated patients were followed-up every 3-6 months for 2 years. Results Eight patients were studied. All patients had tumor involvement restricted to the mucosa or submucosa and seven patients had low-grade gastric MALT lymphoma. All infected patients achieved H pylori eradication. Histological tumor regression was observed in 5/7 (71% of the low-grade gastric MALT lymphoma patients. The presence of t(11;18(q21;q21 translocation was found in 4 (57% of these patients; among them only two had histological tumor regression following H pylori eradication. Conclusions RT-PCR is a feasible and efficient method to detect t(11;18(q21;q21 translocation, being carried out in routine molecular biology laboratories. The early detection of such translocation can be very helpful for better targeting the therapy to be applied to gastric MALT lymphoma patients.

  14. A framework for assessing the feasibility of native fish conservation translocations: Applications to threatened bull trout

    Science.gov (United States)

    Galloway, Benjamin T.; Muhlfeld, Clint C.; Guy, Christopher S.; Downs, Christopher C.; Fredenberg, Wade A.

    2016-01-01

    There is an urgent need to consider more aggressive and direct interventions for the conservation of freshwater fishes that are threatened by invasive species, habitat loss, and climate change. Conservation introduction (moving a species outside its indigenous range to other areas where conditions are predicted to be more suitable) is one type of translocation strategy that fisheries managers can use to establish new conservation populations in areas of refugia. To date, however, there are few examples of successful conservation-based introductions. Many attempts fail to establish new populations—in part because environmental factors that might influence success are inadequately evaluated before the translocation is implemented. We developed a framework to assess the feasibility of rescuing threatened fish populations through translocation into historically unoccupied stream and lake habitats. The suitability of potential introduction sites was evaluated based on four major components: the recipient habitat, recipient community, donor population, and future threats. Specific questions were then developed to evaluate each major component. The final assessment was based on a scoring system that addressed each question by using criteria developed from characteristics representative of highly suitable habitats and populations. This framework was used to evaluate the proposed within-drainage translocation of three Bull Trout Salvelinus confluentus populations in Glacier National Park, Montana. Our results indicated that within-drainage translocation is a feasible strategy for conserving locally adapted populations of Bull Trout through the creation of new areas of refugia in Glacier National Park. The framework provides a flexible platform that can help managers make informed decisions for moving threatened fishes into new areas of refugia for conservation and recovery programs.

  15. Carnivore translocations and conservation: insights from population models and field data for fishers (Martes pennanti.

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    Jeffrey C Lewis

    Full Text Available Translocations are frequently used to restore extirpated carnivore populations. Understanding the factors that influence translocation success is important because carnivore translocations can be time consuming, expensive, and controversial. Using population viability software, we modeled reintroductions of the fisher, a candidate for endangered or threatened status in the Pacific states of the US. Our model predicts that the most important factor influencing successful re-establishment of a fisher population is the number of adult females reintroduced (provided some males are also released. Data from 38 translocations of fishers in North America, including 30 reintroductions, 5 augmentations and 3 introductions, show that the number of females released was, indeed, a good predictor of success but that the number of males released, geographic region and proximity of the source population to the release site were also important predictors. The contradiction between model and data regarding males may relate to the assumption in the model that all males are equally good breeders. We hypothesize that many males may need to be released to insure a sufficient number of good breeders are included, probably large males. Seventy-seven percent of reintroductions with known outcomes (success or failure succeeded; all 5 augmentations succeeded; but none of the 3 introductions succeeded. Reintroductions were instrumental in reestablishing fisher populations within their historical range and expanding the range from its most-contracted state (43% of the historical range to its current state (68% of the historical range. To increase the likelihood of translocation success, we recommend that managers: 1 release as many fishers as possible, 2 release more females than males (55-60% females when possible, 3 release as many adults as possible, especially large males, 4 release fishers from a nearby source population, 5 conduct a formal feasibility assessment, and

  16. Photoinactivation of mcr-1 positive Escherichia coli

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    Caires, C. S. A.; Leal, C. R. B.; Rodrigues, A. C. S.; Lima, A. R.; Silva, C. M.; Ramos, C. A. N.; Chang, M. R.; Arruda, E. J.; Oliveira, S. L.; Nascimento, V. A.; Caires, A. R. L.

    2018-01-01

    The emergence of plasmid-mediated colistin resistance in Enterobacteriaceae, mostly in Escherichia coli due to the mcr-1 gene, has revealed the need to develop alternative approaches in treating mcr-1 positive bacterial infections. This is because colistin is a broad-spectrum antibiotic and one of the ‘last-resort’ antibiotics for multidrug resistant bacteria. The present study evaluated for the first time, to the best of our knowledge, the efficacy of photoinactivation processes to kill a known mcr-1 positive E. coli strain. Eosin methylene-blue (EMB) was investigated as a photoantimicrobial agent for inhibiting the growth of a mcr-1 positive E. coli strain obtained from a patient with a diabetic foot infection. The photoantimicrobial activity of EMB was also tested in a non-multidrug resistant E. coli strain. The photoinactivation process was tested using light doses in the 30-45 J cm-2 range provided by a LED device emitting at 625 nm. Our findings demonstrate that a mcr-1 positive E. coli strain is susceptible to photoinactivation. The results show that the EMB was successfully photoactivated, regardless of the bacterial multidrug resistance; inactivating the bacterial growth by oxidizing the cells in accordance with the generation of the oxygen reactive species. Our results suggest that bacterial photoinactivation is an alternative and effective approach to kill mcr-1 positive bacteria.

  17. Profiling of Escherichia coli Chromosome database.

    Science.gov (United States)

    Yamazaki, Yukiko; Niki, Hironori; Kato, Jun-ichi

    2008-01-01

    The Profiling of Escherichia coli Chromosome (PEC) database (http://www.shigen.nig.ac.jp/ecoli/pec/) is designed to allow E. coli researchers to efficiently access information from functional genomics studies. The database contains two principal types of data: gene essentiality and a large collection of E. coli genetic research resources. The essentiality data are based on data compilation from published single-gene essentiality studies and on cell growth studies of large-deletion mutants. Using the circular and linear viewers for both whole genomes and the minimal genome, users can not only gain an overview of the genome structure but also retrieve information on contigs, gene products, mutants, deletions, and so forth. In particular, genome-wide exhaustive mutants are an essential resource for studying E. coli gene functions. Although the genomic database was constructed independently from the genetic resources database, users may seamlessly access both types of data. In addition to these data, the PEC database also provides a summary of homologous genes of other bacterial genomes and of protein structure information, with a comprehensive interface. The PEC is thus a convenient and useful platform for contemporary E. coli researchers.

  18. Crucial role of Asp408 in the proton translocation pathway of multidrug transporter AcrB: evidence from site-directed mutagenesis and carbodiimide labeling.

    Science.gov (United States)

    Seeger, Markus A; von Ballmoos, Christoph; Verrey, François; Pos, Klaas M

    2009-06-30

    The three-component AcrA/AcrB/TolC efflux system of Escherichia coli catalyzes the proton motive force-driven extrusion of a variety of cytotoxic compounds. The inner membrane pump component AcrB belongs to the resistance nodulation and cell division (RND) superfamily and is responsible for drug specificity and energy transduction of the entire tripartite efflux system. Systematic mutational analysis of titratable and polar membrane-located amino acids revealed four residues, D407, D408, K940, and, R971, to be of prime importance for AcrB function. Using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry, D408 was shown to specifically react with dicyclohexylcarbodiimide (DCCD) in a pH-dependent manner. The apparent pK(a) of D408 of 7.4 would enable binding and release of protons under physiological conditions. In contrast to other secondary transporters, D408 was not protected from carbodiimide modification in the presence of drugs, which supports the notion of spatially separated transport pathways for drugs and protons. This study provides evidence for a substantial role of membrane-located carboxylates as a central element of the proton translocation pathway in AcrB and other members of the RND superfamily.

  19. Extracellular overexpression of recombinant Thermobifida fusca cutinase by alpha-hemolysin secretion system in E. coli BL21(DE3

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    Su Lingqia

    2012-01-01

    Full Text Available Abstract Background Extracellular expression of proteins has an absolute advantage in a large-scale industrial production. In our previous study, Thermobifida fusca cutinase, an enzyme mainly utilized in textile industry, was expressed via type II secretory system in Escherichia coli BL21(DE3, and it was found that parts of the expressed protein was accumulated in the periplasmic space. Due to the fact that alpha-hemolysin secretion system can export target proteins directly from cytoplasm across both cell membrane of E. coli to the culture medium, thus in the present study we investigated the expression of cutinase using this alpha-hemolysin secretion system. Results T. fusca cutinase was fused with the specific signal peptide of alpha-hemolysin scretion system and expressed in E. coli BL21(DE3. In addition, HlyB and HlyD, strain-specific translocation components of alpha-hemolysin secretion system, were coexpressed to facilitate the enzyme expression. The cultivation of this engineered cell showed that cutinase activity in the culture medium reached 334 U/ml, which is 2.5 times that from type II secretion pathway under the same culture condition. The recombinant cutinase was further purified. Biochemical characterization of purified enzyme, which had an α-hemolysin secretion pathway signal peptide attached, had substrate specificity, pH and temperature profile, as well as application capability in bioscouring similar to that of wild-type cutinase. Conclusions In the present study, T. fusca cutinase was successfully secreted to the culture media by α-hemolysin secretion system. This is the first report of cutinase being efficiently secreted by this pathway. Due to the limited cases of successful expression of industrial enzyme by E. coli α-hemolysin secretion system, our study further explored the utilization of this pathway in industrial enzymes.

  20. Mucin2 is Required for Probiotic Agents-Mediated Blocking Effects on Meningitic E. coli-Induced Pathogenicities.

    Science.gov (United States)

    Yu, Jing-Yi; He, Xiao-Long; Puthiyakunnon, Santhosh; Peng, Liang; Li, Yan; Wu, Li-Sha; Peng, Wen-Ling; Zhang, Ya; Gao, Jie; Zhang, Yao-Yuan; Boddu, Swapna; Long, Min; Cao, Hong; Huang, Sheng-He

    2015-10-01

    Mucin2 (MUC2), an important regulatory factor in the immune system, plays an important role in the host defense system against bacterial translocation. Probiotics known to regulate MUC2 gene expression have been widely studied, but the interactions among probiotic, pathogens, and mucin gene are still not fully understood. The aim of this study was to investigate the role of MUC2 in blocking effects of probiotics on meningitic E. coli-induced pathogenicities. In this study, live combined probiotic tablets containing living Bifidobacterium, Lactobacillus bulgaricus, and Streptococcus thermophilus were used. MUC2 expression was knocked down in Caco-2 cells by RNA interference. 5-Aza-2'-deoxycytidine (5-Aza-CdR), which enhances mucin-promoted probiotic effects through inducing production of Sadenosyl- L-methionine (SAMe), was used to up-regulate MUC2 expression in Caco-2 cells. The adhesion to and invasion of meningitic E. coli were detected by competition assays. Our studies showed that probiotic agents could block E. coli-caused intestinal colonization, bacteremia, and meningitis in a neonatal sepsis and meningitis rat model. MUC2 gene expression in the neonatal rats given probiotic agents was obviously higher than that of the infected and uninfected control groups without probiotic treatment. The prohibitive effects of probiotic agents on MUC2-knockdown Caco-2 cells infected with E44 were significantly reduced compared with nontransfected Caco-2 cells. Moreover, the results also showed that 5- Aza-CdR, a drug enhancing the production of SAMe that is a protective agent of probiotics, was able to significantly suppress adhesion and invasion of E44 to Caco-2 cells by upregulation of MUC2 expression. Taken together, our data suggest that probiotic agents can efficiently block meningitic E. coli-induced pathogenicities in a manner dependent on MUC2.