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Burial dolomitization, the genesis of dolomite in the Dapu Formation (Upper carboniferous), Guixinan area, Youjiang basin, Southwest china: petrologic and geochemical evidence

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cARBONATES AND EVAPORITES 2020年第2期35卷 1-14页

作者： Miao, Zhuowei Gong, Enpu Zhang, Yongli Guan, changqing Huang, Wentao Northeastern Univ Resources & Civil Engn Coll Shenyang 110819 Liaoning Peoples R China

The genesis of dolomite is an intensively debated and extensively studied problem in the field of carbonate sedimentology. This study focuses on the dolomite of the Dapu Formation in the Guixinan area, with the aim of deciphering the mechanism of dolomitization in the Dapu Formation. Three types of sedimentary environment, including the open marine of inner ramp, the restricted marine of inner ramp, and the shoal of inner ramp, have been identified. Three types of dolostone (DI, DII and DIII) identified in the study area with massive structure had close relationship with fault structures, and contacted with limestone in curved diffuse way on the outcrop. Both of the above points indicated diagenetic dolomite. Three types of dolomite (D1, D2 and D3) displayed similar dark-light purple red luminescence, indicating that the characteristics of their diagenetic fluids were similar. The planar-s to nonplanar dolomite crystals indicated that the temperature was more than 50 degrees c. The mineral assemblage including D2, D3, and silicate minerals (feldspar, tremolite and actinolite) suggested contact metamorphism and tht the diagenetic fluid was rich in silicon and magnesium. The dolomitization process was not influenced by the leaching of meteoric water in surface or shallow buried environment and hydrothermal fluids, based on the corrected REE characteristics. The range of the delta O-18 of dolostone samples showed that the burial dolomitization had taken place in high-temperature environment. The lower Sr-87/Sr-86 ratio of the dolostone samples than the coeval seawater meant that the diagenetic fluid was derived from the alteration of mid-ocean ridge basalt. Based on the geologic setting, it was speculated that the burial dolomitization was driven by the hydro-tectonic processes in the passive margin burial diagenesis hydrologic realm. In brief, magnesium came from the low-temperature alteration of ocean basalts, the thermohaline and compactional flow supplied hydrodyna

关键词： c O Sr isotopes Burial dolomitization Dolomite Dapu Formation Passive margin Rare earth elements

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PAPAIN-DERIVED FRAGMENT-IIc OF TETANUS TOXIN - ITS BINDING TO ISOLATED SYNAPTIc-MEMBRANES AND RETROGRADE AXONAL-TRANSPORT

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BRAIN RESEARcH 1981年第1-2期210卷 291-299页

作者： BIZZINI, B GROB, P AKERT, K UNIV ZURICH INST BRAIN RESCH-8029 ZURICHSWITZERLAND INST PASTEUR F-92420 MARNES LA COQUETTFRANCE

The papain-derived fragment II(c) of tetanus toxin, which is immunologically identical to the B-II(b) fragment, has previously been shown to bind gangliosides. As could be expected from its analogy with the B-II(b) fragment, the II(c) fragment was also found to bind to isolated synaptic membranes and to be transported retrogradely from the axonal endings within muscle to the motorneuronal perikarya. It is concluded that the II(c) fragment - like the B-II(b) fragment - might also serve as a specific carrier for chemical and chemotherapeutical agents into the central nervous system.

关键词： tetanus toxin retrograde axonal transport II c fragment synaptic membranes

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EXPRESSION OF THE MULTIDRUG RESISTANcE GENE IN MYELOID LEUKEMIAS

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LEUKEMIA RESEARcH 1990年第1期14卷 11-+页

作者： SATO, H GOTTESMAN, MM GOLDSTEIN, LJ PASTAN, I BLOcK, AM SANDBERG, AA PREISLER, HD BARRETT CTR CANC PREVENT RES & TREATMENT 234 GOODMAN AVE CINCINNATI OH 45267 USA

The human multidrug-resistance gene (MDR1) encodes an energy-dependent multidrug efflux protein responsible for the cross-resistance of cultured cells to natural product chemotherapeutic agents such as the anthracyclines and vinca alkaloids. RNA transcript levels were measured in leukemia cells obtained from 15 adult acute nonlymphotic leukemia (ANLL) cases and 15 cases of chronic myelogenous leukemia (cML). Expression of MDR1 RNA was common in ANLL, and appears to be most frequent in leukemic cells of patients with the poorest response to chemotherapy. Expression of the MDR1 gene was not detectable in the peripheral white blood cells of any of the cML cases during the chronic phase, but was detectable in the immature cells present during this phase of the disease. The cells of the three blastic crisis patients contained detectable levels of MDR1 RNA. These studies support the idea that expression of the MDR1 gene contributes to drug resistance in ANLL, and may play a role in some instances in the drug-resistance of cML in blastic crisis. In contrast, studies of the level of expression of anionic glutathione transferase and DNA polymerase B failed to show any relationship between the RNA transcript levels of these enzymes and responsiveness to chemotherapy.

关键词： Multidrug resistance AML cML HL , HL-60 Nc , RNS from nonresistant chinese hamster ovary cell line AUXB1 Pc , RNA from colcicine-resistant chinese hamster ovary cell line MDR1 , multidrug resistant gene GST-P , anionic glutathione transferase H 4, histone H4 B-PLM , DNA polymerase M , bone marrow specimen P , peripheral blood specimen c -mye, proto-oncogene c- myc TPI , triose phosphate isomerate

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The Acid-Dependent and Independent Effects of Lactobacillus acidophilus cL1285, Lacticaseibacillus casei LBc80R, and Lacticaseibacillus rhamnosus cLR2 on clostridioides difficile R20291

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PROBIOTIcS AND ANTIMIcROBIAL PROTEINS 2021年第4期13卷 949-956页

作者： Gunaratnam, Sathursha Diarra, carine Paquette, Patrick D. Ship, Noam Millette, Mathieu Lacroix, Monique Ctr Armand Frappier Sante Biotechnol Inst Natl Rech Sci 531 Blvd Prairies Laval PQ H7V 1B7 Canada BioK Plus Int Inc 495 Blvd Armand Frappier Laval PQ H7V 4B3 Canada

clostridioides difficile infections (cDI) result from antibiotic use and cause severe diarrhea which is life threatening and costly. A specific probiotic containing Lactobacillus acidophilus cL1285, Lacticaseibacillus casei LBc80R, and Lacticaseibacillus rhamnosus cLR2 has demonstrated a strong inhibitory effect on the growth of several nosocomial c. difficile strains by production of antimicrobial metabolites during fermentation. Though there are several lactobacilli shown to inhibit c. difficile growth by processes relying on acidification, this probiotic has demonstrated potency for cDI prevention among hospitalized patients. Here, we describe the acid-dependent and independent mechanisms by which these strains impair the cytotoxicity of a hypervirulent strain, c. difficile R20291 (cD). These bacteria were co-cultured in a series of experiments under anaerobic conditions in glucose-rich and no-sugar medium to inhibit or stimulate cD toxin production, respectively. In glucose-rich medium, there was low cD toxin production, but sufficient amounts to cause cytotoxic damage to human fibroblast cells. In co-culture, there was acidification by the lactobacilli resulting in growth inhibition as well as >= 99% reduced toxin A and B production and no observable cytotoxicity. In the absence of glucose, cD produced much more toxin. In co-culture, the lactobacilli did not acidify the medium and cD growth was unaffected;yet, the amount of detected toxin A and B was decreased by 20% and 41%, respectively. Despite the high concentration of toxin, cells exposed to the supernatant from the co-culture were able to survive. These results suggest that in addition to known acid-dependent effects, the combination of L. acidophilus cL1285, L. casei LBc80R, and L. rhamnosus cLR2 can interfere with cD pathogenesis without acidification: (1) reduced toxin A and B production and (2) toxin neutralization. This might explain the strain specificity of this probiotic in potently preventing c.

关键词： c difficile Lactobacillus Probiotic Antibiotic Infection Pathogenesis microbiota colonization resistance Infection control Preventive intervention L acidophilus cL1285 L casei LBc80R L rhamnosus cLR2

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Homologous complement activation on drug-induced apoptotic cells from a human lung adenocarcinoma cell line

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IMMUNOBIOLOGY 1997年第5期196卷 491-503页

作者： Hara, T Matsumoto, M Tsuji, S Nagasawa, S Hiraoka, A Masaoka, T Kodama, K Horai, T Sakuma, T Seya, T CTR ADULT DIS DEPT IMMUNOL & CELL BIOLOSAKA 537JAPAN CTR ADULT DIS DEPT HEMATOLOSAKA 537JAPAN HOKKAIDO UNIV DEPT PHARMACEUT SCISAPPOROHOKKAIDO 060JAPAN JRDC PRESTOKYOTOJAPAN

Activation of the alternative pathway of homologous complement (c) was observed in a human lung adenocarcinoma cell line, cADO 43, after the cells had become apoptotic following treatment in vitro With vincristine and predonisolone. Deposition of c3b and c3bi on the serum-treated apoptotic cells was revealed by flow cytometry with anti-c3b and -c3bi-specific antibodies and immunoblotting with anti-c3 antibody immunoprecipitates extracted from solubilized fractions of serum-treated apoptotic cells. Two molecular mechanisms were found to be responsible for this post-apoptotic c-activation. Firstly, all c regulators, decay accelerating factor (DAF), membrane cofactor protein (McP) and c3b/c4b receptor (cRI), were diminished on the cell surface concomitantly with the apoptotic process. Secondly, unidentified molecules which potentially activate homologous c and accept c3b/c3bi fragments became expressed on the cell surface during the apoptotic process. These findings may explain the mechanism whereby tumor cells are efficiently eliminated through chemotherapy.

关键词： c complement cRI c3b/c4b receptor cR2 c3d/Epstein-Barr virus receptor DAF decay accelerating factor (cD55) GPI glycanphosphatidylinositol McP membrane cofactor protein (cD46) NHS normal human serum PBS phosphate buffered saline PI propidium iodide TdT terminal deoxytransferase

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Oxidative stress and longevity in caenorhabditis elegans as mediated by SKN-1

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AGING cELL 2009年第3期8卷 258-269页

作者： Park, Sang-Kyu Tedesco, Patricia M. Johnson, Thomas E. Univ Colorado Inst Behav Genet Boulder CO 80309 USA

Oxidative stress has been hypothesized to play a role in normal aging. The response to oxidative stress is regulated by the SKN-1 transcription factor, which also is necessary for intestinal development in caenorhabditis elegans. Almost a thousand genes including the antioxidant and heat-shock responses, as well as genes responsible for xenobiotic detoxification were induced by the oxidative stress which was found using transcriptome analysis. There were also 392 down-regulated genes including many involved in metabolic homeostasis, organismal development, and reproduction. Many of these oxidative stress-induced transcriptional changes are dependent on SKN-1 action;the induction of the heat-shock response is not. When RNAi to inhibit genes was used, most had no effect on either resistance to oxidative stress or longevity;however two SKN-1-dependent genes, nlp-7 and cup-4, that were up-regulated by oxidative stress were found to be required for resistance to oxidative stress and for normal lifespan. nlp-7 encodes a neuropeptide-like protein, expressed in neurons, while cup-4 encodes a coelomocyte-specific, ligand-gated ion channel. RNAi of nlp-7 or cup-4 increased sensitivity to oxidative stress and reduced lifespan. Among down-regulated genes, only inhibition of ent-1, a nucleoside transporter, led to increased resistance to oxidative stress;inhibition had no effect on lifespan. In contrast, RNAi of nhx-2, a Na+/H+ exchanger, extended lifespan significantly without affecting sensitivity to oxidative stress. These findings showed that a transcriptional shift from growth and maintenance towards the activation of cellular defense mechanisms was caused by the oxidative stress;many of these transcriptional alterations are SKN-1 dependent.

关键词： aging c elegans longevity microarray oxidative stress SKN-1

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MELTING OF AN INFINITE SOLID WITH A SPHERIcAL cAVITY

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INTERNATIONAL JOURNAL OF ENGINEERING ScIENcE 1973年第12期11卷 1277-1295页

作者： LEE, YF BOLEY, BA CORNING GLASS WORKS CORNINGNY 14830 CORNELL UNIV DEPT THEORET & APPL MECHITHACANY 14850

The embedding technique is employed to obtain the short time exact analytical solution for the melting or solidification of an infinite body with a spherical cavity, with melting or solidification starting from the interior surface of the cavity. General cases of zero and infinite rates of ablation are considered, with particular emphasis on the Neumann problem and the case corresponding to a sudden rise of temperature. Numerical results are presented, and the validity and accuracy of the solutions are briefly discussed. La technique d'inclusion est utilisée pour obtenir la solution analytique exacte pour la fusion ou la soliditication en un temps court d'un corps infini avec une cavité sphérique, la fusion ou la solidification commençant à partir de la surface interne de la cavité. Des cas généraux de taux unls et infinis d'ablation sont considérés, en insistant particulièrement sur le problème de Neumann et sur le cas correspondant à une montée brusque de température. Des résultats numériques sont présentés, et la validité et la précision des solutions font l'objet d'une brève discussion. Es wird das Einbettungsverfahren verwendet, um die kurzzeitige exakte analytische Lösung für das Schmelzen oder die Verfestigung eines unendlichen Körpers mit einer kugelförmigen Höhlung zu erhalten, wobei Schmelzen oder Verfestigung von der Innenfläche der Höhlung ausgehen. Es werden allgemeine Fälle von Null- und Unendlichraten von Ablation untersucht, mit besonderer Beachtung des Neumann-Problemes und des Falles, der einem plötzlichen Temperaturanstieg entspricht. Es werden numerische Resultate vorgelegt und die Gültigkeit und Genquigkeit der Lösungen werden kurz besprochen. Ma tecnica di incassatura viene impiegata per ottenere la soluzione analitica esatta in breve tempo per la fusione o la solidificazione di un solido infinito con una cavitá sferica, in cui la fusione o la solidificazione comincia dalla superficie interna della cavitá. Vengono considerati i casi generali di

关键词： α radius of the spherical cavity c specific heat D non-dimensional thermal diffusivity defined by equation (4.4) G Green's function k thermal conductivity K thermal diffusivity k 1 non-dimensional thermal conductivity defined by equation (4.4) l latent heat of melting m non-dimensional material property defined by equation (3.4) Q heat-input Q 0 reference heat-input defined by equation (3.4) Q ′ fictitious heat-input Q 1 heat-input at liquid-solid interface Q ∗ analytic continuation of the actual heat-input r radial coordinate R non-dimensional radial coordinate defined by equation (3.4) s radius of the liquid-solid interface t time t m time for melt initiation T temperature T m melt temperature of material T 0 Green's function T ′ temperature distribution due to fictitious heat-input Q ′ T ∗ analytic continuation of the pre-melt temperature T ∗∗ temperature distribution due to a prescribed temperature V at r = a T θ temperature distribution due to fictitious initial temperature T m θ V prescribed temperature on the inner exposed surface of the cavity X depth of melted material y non-dimensional time defined by equation (3.4) θ non-dimensional fictitious initial temperature ξ non-dimensional location of the liquid-solid interface defined by equation (3.4) ρ density ψ non-dimensional parameter defined by equation (4.4) S variable associated with solid L variable associated with liquid

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cOMPARATIVE EFFEcTS OF THYROID-HORMONE ANALOGS ON THE AcTIVITIES OF BRAIN AND LIVER-MITOcHONDRIA AND NUcLEI IN THYROIDEcTOMIZED RATS

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MOLEcULAR AND cELLULAR ENDOcRINOLOGY 1984年第2期37卷 223-232页

作者： DEMBRI, A MIcHEL, R MIcHEL, O BELKHIRIA, M JORGENSEN, Ec COLL FRANCE F-75231 PARIS 05 FRANCE FDN RECH HORMONOL F-94260 FRESNES FRANCE

Several thyroid hormone analogs [L-thyroxine, 3,5,3''-triiodo-L-thyronine [T3], 3,5-diiodo-3''-isopropyl-L-thyronine;3,5-dimethyl-3''-isopropyl-L-thyronine;3,5,3''-triiodothyroacetic acid;3,5-diiodo-3''-isopropylthyroacetic acid;and 3,5-diiodo-4-(4-hydroxy-3-isopropylbenzoyl)-phenylacetic acid] were tested for thyromimetic activity on rat brain and liver subcellular organelles. The compounds were administered immediately after thyroidectomy to 90 g male S-D rats for 10 days by daily s.c. injection. In cerebral cortex and liver were measured the activities of mitochondrial succinate cytochrome c reductase and .alpha.-GPD [.alpha.-glycerophosphate dehydrogenase], and nuclear RNA polymerase I. Brain mitochondrial enzymes were unchanged in thyroidectomized (Tx) and in Tx-treated rats, whereas the activities of these enzymes in liver mitochondria were partially restored by the treatments. RNA polymerase I activity in brain and liver dropped significantly 10 days after thyroidectomy, and daily injection of thyroid hormones or analogs maintained the nuclear activity at a normal level. correlation between the structure of thyroid hormone analogs and their subcellular effects is in good agreement with previous binding and in vivo studies. Enzyme activities stimulated by T3 were lowered by replacing the T3 side-chain by an acetic acid group or by substituting the bridged oxygen atom by atom by cO. In contrast, the activity was enhanced by substituting iodine with a 3'' isopropyl group. Although less active than iodine, the 3,5-dimethyl substituents may be introduced without a complete loss of nuclear activity.

关键词： thyroid hormone analogs succinate cytochrome c reductase α-GPD RNA polymerase rat brain and liver

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Priming effect and microbial diversity in ecosystem functioning and response to global change: a modeling approach using the SYMPHONY model

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GLOBAL cHANGE BIOLOGY 2014年第4期20卷 1174-1190页

作者： Perveen, Nazia Barot, Sebastien Alvarez, Gael Klumpp, Katja Martin, Raphael Rapaport, Alain Herfurth, Damien Louault, Frederique Fontaine, Sebastien INRA Unite Rech Ecosyst Prairial UR874 F-63039 Clermont Ferrand France Ecole Normale Super IRD UMR BIOEMCO Biogeochim & Ecol Milieux Continentau F-75230 Paris France Univ Clermont Ferrand 2 VetAgro Sup F-6300 Clermont Ferrand France SupAgro MISTEA UMR INRA F-34060 Montpellier France INRIA MODEMIC EPI INRA F-34060 Montpellier France

Integration of the priming effect (PE) in ecosystem models is crucial to better predict the consequences of global change on ecosystem carbon (c) dynamics and its feedbacks on climate. Over the last decade, many attempts have been made to model PE in soil. However, PE has not yet been incorporated into any ecosystem models. Here, we build plant/soil models to explore how PE and microbial diversity influence soil/plant interactions and ecosystem c and nitrogen (N) dynamics in response to global change (elevated cO2 and atmospheric N depositions). Our results show that plant persistence, soil organic matter (SOM) accumulation, and low N leaching in undisturbed ecosystems relies on a fine adjustment of microbial N mineralization to plant N uptake. This adjustment can be modeled in the SYMPHONY model by considering the destruction of SOM through PE, and the interactions between two microbial functional groups: SOM decomposers and SOM builders. After estimation of parameters, SYMPHONY provided realistic predictions on forage production, soil c storage and N leaching for a permanent grassland. consistent with recent observations, SYMPHONY predicted a cO2-induced modification of soil microbial communities leading to an intensification of SOM mineralization and a decrease in the soil c stock. SYMPHONY also indicated that atmospheric N deposition may promote SOM accumulation via changes in the structure and metabolic activities of microbial communities. collectively, these results suggest that the PE and functional role of microbial diversity may be incorporated in ecosystem models with a few additional parameters, improving accuracy of predictions.

关键词： bank functioning c sequestration c N coupling nutrient cycling nutrient mining plant soil interactions

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EFFEcT OF cALcIUM ON THE INTERAcTIONS BETWEEN cA-2+-ATPASE MOLEcULES IN SARcOPLASMIc-RETIcULUM

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BIOcHIMIcA ET BIOPHYSIcA AcTA 1989年第3期984卷 326-338页

作者： KERESZTES, T JONA, I PIKULA, S VEGH, M MULLNER, N PAPP, S MARTONOSI, A SUNY HLTH SCI CTR DEPT BIOCHEM & MOLEC BIOL SYRACUSE NY 13210 USA

The interaction between ca2+-ATPase molecules in the native sarcoplasmic reticulum membrane and in detergent solutions was analyzed by chemical crosslinking, high performance liquid chromatography (HPLc), and by the polarization of fluorescence of fluorescein 5''-isothiocyanate (FITc) covalently attached to the ca2+-ATPase. Reaction of sarcoplasmic reticulum vesicles with glutaraldehyde causes the crosslinking of ca2+-ATPase molecules with the formation of dimers, tetramers and higher oligomers. At moderate concentrations of glutaraldehyde solubilization of sarcoplasmic reticulum by c12E8 or Brij 36T (.simeq. 4 mg/mg protein) decreased the formation of higher oligomers without significant interference with the appearance of crosslinked ATPase dimers. These observations are consistent with the existence of ca2+-ATPase dimers in detergent-solubilized sarcoplasmic reticulum. ca2+ (2-20 mM) and glycerol (10-20%) increased the degree of crosslinking at pH 6.0 both in vesicular and in solubilized sarcoplasmic reticulum, presumably by promoting interactions between ATPase molecules;at pH 7.5 the effect of ca2+ was less pronounced. In agreement with these observations, high performance liquid chromatography of sarcoplasmic reticulum proteins solubilized by Brij 36T or c12E10 revealed the presence of components with the expected elution characteristics of ca2+-ATPase oligomers. The polarization of fluorescence of FITc covalently attached to the ca2+-ATPase is low in the native sarcoplasmic reticulum due to energy transfer, consistent with the existence of ATPase oligomers (Highsmith, S. and cohen, J.A. (1987) Biochemistry 26, 154-161);upon solubilization of the sarcoplasmic reticulum by detergents, the polarization of fluorescence increased due to dissociation of ATPase oligomers. Based on its effects on the fluorescence of FITc-ATPase, ca2+ promoted the interaction between ATPase molecules, both in the native membrane and in detergent solutions.

关键词： calcium ion effect ATPase, ca 2+ - ATPase dimer Sarcoplasmic reticulum Brij-36T polyoxyethylene 10 lauryl ether c 12 E 8 octaethyleneglycol dodecyl ether c 12 E 9 polyoxyethylene 9 lauryl ether c 12 E 10 polyoxyethylene 10 lauryl ether DOc deoxycholate DTT dithiothreitol EFTA ethylene glycol bis( β -aminoethyl ether)- N , N , N ′, N ′-tetraacetic acid FITc fluorescein-5′-isothiocyanate HPLc high performance liquid chromatography Mops 4-morpholinepropanesulfonic acid SDS sodium dodecyl sulfate SR sarcoplasmic reticulum Tes N -[tris(hydroxymethyl)methyl″]-2-aminoethanesulfonic acid

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