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221.
Marcotullio MC Pagiotti R Maltese F Oball-Mond Mwankie GN Hoshino T Obara Y Nakahata N 《Bioorganic & medicinal chemistry》2007,15(8):2878-2882
Two new cyathane diterpenes, cyrneine C (4) and D (5), were isolated from the mushroom Sarcodon cyrneus, along with previously isolated cyrneine A, B and glaucopine C. The structures of the novel diterpenoids were determined by the analysis of spectroscopic data. Effects of the cyrneines and glaucopine C on the NGF gene expression in 1321N1 cells and on neurite outgrowth on PC12 cells were evaluated. 相似文献
222.
Bryan J. Culbertson Jaymie Krone Erastus Gatebe Norbert C. Furumo Steven L. Daniel 《World journal of microbiology & biotechnology》2007,23(10):1357-1362
The impact of various supplemental carbon sources (oxalate, glyoxylate, glycolate, pyruvate, formate, malate, acetate, and
succinate) on growth and oxalate formation (i.e., oxalogenesis) by Sclerotinia sclerotiorum was studied. With isolates D-E7, 105, W-B10, and Arg-L of S. sclerotiorum, growth in an undefined broth medium (0.1% soytone; pH 5) with 25 mM glucose and 25 mM supplemental carbon source was increased
by the addition of malate and succinate. Oxalate accumulation occurred in the presence of glucose and a supplemental carbon
source, with malate, acetate, and succinate supporting the most oxalate synthesis. With S. sclerotiorum Arg-L, oxalate-to-biomass ratios, an indicator of oxalogenic potential, were dissimilar when the organism was grown in the
presence of different carbon sources. The highest oxalate-to-biomass ratios were observed with pyruvate, formate, malate,
acetate, and succinate. Time-course studies with acetate-supplemented cultures revealed that acetate and glucose consumption
by S. sclerotiorum D-E7 coincided with oxalogenesis and culture acidification. By day 5 of incubation, oxalogenesis was halted when cultures
reached a pH of 3 and were devoid of acetate. In succinate-supplemented cultures, oxalogenesis essentially paralleled glucose
and succinate utilization over the 9-day incubation period; during this time period, culture pH declined but never fell below
4. Overall, these results indicate that carbon sources can regulate the accumulation of oxalate, a key pathogenicity determinant
for S. sclerotiorum. 相似文献
223.
224.
Chrenek P Trandzik J Massanyi P Makarevich A Lukac N Peskovicova D Paleyanda R 《Animal reproduction science》2007,99(1-2):127-134
The influence of foreign transgene integration on the reproductive capabilities of rabbit males is not known. Therefore, we analyzed their ejaculate characteristics, reproductive capabilities, occurrence of pathological spermatozoa and histological structure of the testis. We have generated transgenic rabbits by microinjection of WAP-hFVIII gene into pronucleus of fertilized egg. We observed that the libido, volume and pH value of the ejaculate did not differ significantly between transgenic and non-transgenic male lines. The motility, concentration, osmolarity, thermoresistant test of spermatozoa (at 1 or 6 h) and the percentage of alive spermatozoa were significantly different (p < 0.001) among transgenic and non-transgenic males. No significant differences were found between transgenic and non-transgenic male lines in the occurrence of pathological spermatozoa and histology of the testis. The ability of spermatozoa from transgenic and non-transgenic males to fertilize eggs was ranged within 96 and 100%; while the yield of transgenic embryos ranged from 43 to 57%. Our results show that mammary gland specific over-expression mWAP-hFVIII gene construct does not affect reproductive traits of transgenic rabbit males. 相似文献
225.
Fetal and early post-natal development of the human spleen: from primordial arterial B cell lobules to a non-segmented organ 总被引:2,自引:2,他引:0
Immunohistological analysis of 31 human spleens from the 11th week of gestation to the early postnatal period suggested that
fetal organ development may be preliminarily divided into four stages. At stage 0 the organ anlage contained erythrocyte precursors,
few macrophages and almost no lymphocytes. Fetal spleens of stage I exhibited arterial vascular lobules and lymphocytes just
began colonizing the organ. At stage II, B and T lymphocytes formed periarteriolar clusters. B cell clusters predominated,
because B cells aggregated around the more peripheral branches of splenic arterioles, while T cells occupied the more centrally
located parts of the vessels. The vascular lobules of stage I and II consisted of central arterioles surrounded by B cells,
capillaries and peripheral venules. The lobular architecture slowly dissolved at late stage II when sinuses grew out from
the peripheral venules into the centre of the lobule. Interestingly, the B cell accumulations around peripheral arterioles
did not represent the precursors of follicles, but apparently persisted as periarteriolar B cell clusters in the adult splenic
red pulp, while follicles containing FDCs developed at late stage II from B cells in direct contact to T cell clusters around
larger arterial vessels. At stage III before birth the lobular architecture was no longer recognized. The chemokine CXCL13
was already present in vascular smooth muscle and adjacent stromal cells at stage I before B cells immigrated. CCL21, on the
contrary, was only demonstrated in fibroblast-like cells supporting T cell clusters from stage II onwards. 相似文献
226.
Slevogt H Seybold J Tiwari KN Hocke AC Jonatat C Dietel S Hippenstiel S Singer BB Bachmann S Suttorp N Opitz B 《Cellular microbiology》2007,9(3):694-707
Moraxella catarrhalis is an important pathogen in patients with chronic obstructive lung disease (COPD). While M. catarrhalis has been categorized as an extracellular bacterium so far, the potential to invade human respiratory epithelium has not yet been explored. Our results obtained by electron and confocal microscopy demonstrated a considerable potential of M. catarrhalis to invade bronchial epithelial (BEAS-2B) cells, type II pneumocytes (A549) and primary small airway epithelial cells (SAEC). Moraxella invasion was dependent on cellular microfilament as well as on bacterial viability, and characterized by macropinocytosis leading to the formation of lamellipodia and engulfment of the invading organism into macropinosomes, thus indicating a trigger-like uptake mechanism. In addition, the cells examined expressed TLR2 as well as NOD1, a recently found cytosolic protein implicated in the intracellular recognition of bacterial cell wall components. Importantly, inhibition of TLR2 or NOD1 expression by RNAi significantly reduced the M. catarrhalis-induced IL-8 secretion. The role of TLR2 and NOD1 was further confirmed by overexpression assays in HEK293 cells. Overall, M. catarrhalis may employ lung epithelial cell invasion to colonize and to infect the respiratory tract, nonetheless, the bacteria are recognized by cell surface TLR2 and the intracellular surveillance molecule NOD1. 相似文献
227.
Driss Mountassif Mostafa Kabine Rachid Manar Noureddine Bourhim Zaina Zaroual Norbert Latruffe MHammed Saïd El Kebbaj 《Ecological Indicators》2007,7(4):882-894
The individual cytotoxicity of cadmium chloride, iron sulphate and chromium nitrate has been investigated by using the freshwater ciliate Tetrahymena pyriformis. The metabolic enzymes and antioxidant defense biomarkers were assessed. The results obtained reveal that their metal salts have perturbed the physiology and morphology of T. pyriformis. Also, the biomarkers assessed were sensitive to the presence of metal salts and this sensitivity was metal salt and dose dependant. To estimate the impact of their metal salts on mitochondria, we studied their effects in vivo and in vitro on the d-β-hydroxybutyrate dehydrogenase (BDH) (EC 1.1.1.30) inner mitochondrial membrane enzyme. The results showed a high inhibition of BDH in terms of activity, protein expression and kinetic parameters. 相似文献
228.
Protein phosphatase 1 (PP1) catalytic subunits typically combine with other proteins that modulate their activity, direct them to distinct substrates, or serve as substrates for PP1. More than 50 PP1-interacting proteins (PIPs) have been identified so far. Given there are approximately 10 000 phosphoproteins in mammals, many PIPs remain to be discovered. We have used arrays containing 100 carefully selected antibodies to identify novel PIPs that are important in cell proliferation and cell survival in murine fetal lung epithelial cells and human A549 lung cancer cells. The antibody arrays identified 31 potential novel PIPs and 11 of 17 well-known PIPs included as controls, suggesting a sensitivity of at least 65%. A majority of the interactions between PP1 and putative PIPs were isoform- or cell type-specific. We confirmed by co-immunoprecipitation that 9 of these proteins associate with PP1: APAF-1, Bax, E-cadherin, HSP-70, Id2, p19Skp1, p53, PCNA, and PTEN. We examined two of these interactions in greater detail in A549 cells. Exposure to nicotine enhanced association of PP1 with Bax (and Bad), but also induced inhibitory phosphorylation of PP1. In addition to p19Skp1, PP1alpha antibodies also coprecipitated cullin 1, suggesting that PP1alpha is associated with the SCF1 complex. This interaction was only detectable during the G1/S transition and S phase. Forced loss of PP1 function decreased the levels of p27Kip1, a well-known SCF1 substrate, suggesting that PP1 may rescue proteins from ubiquitin/proteasome-mediated destruction. Both of these novel interactions are consistent with PP1 facilitating cell cycle arrest and/or apoptosis. 相似文献
229.
Martin FP Wang Y Sprenger N Holmes E Lindon JC Kochhar S Nicholson JK 《Journal of proteome research》2007,6(4):1471-1481
We have used a simplified gnotobiotic mouse model to evaluate the effects of single bacterial species, Lactobacillus paracasei NCC2461, on the metabolic profiles of intact intestinal tissues using high-resolution magic-angle-spinning 1H NMR spectroscopy (HRMAS). A total of 24 female gnotobiotic mice were divided into three groups: a control group supplemented with water and two groups supplemented with either live L. paracasei or a gamma-irradiated equivalent. HRMAS was used to characterize the biochemical components of intact epithelial tissues from the duodenum, jejunum, ileum, proximal, and distal colons in all animals and data were analyzed using chemometrics. Variations in relative concentrations of amino acids, anti-oxidant, and creatine were observed relating to different physiological properties in each intestinal tissue. Metabolic characteristics of lipogenesis and fat storage were observed in the jejunum and colon. Colonization with live L. paracasei induced region-dependent changes in the metabolic profiles of all intestinal tissues, except for the colon, consistent with modulation of intestinal digestion, absorption of nutrients, energy metabolism, lipid synthesis and protective functions. Ingestion of gamma-irradiated bacteria produced no effects on the observed metabolic profiles. 1H MAS NMR spectroscopy was able to generate characteristic metabolic signatures reflecting the structure and function of intestinal tissues. These signals acted as reference profiles with which to compare changes in response to gut microbiota manipulation at the tissue level as demonstrated by ingestion of a bacterial probiotic. 相似文献
230.
Roldan M de Guia Adam J Rose Anke Sommerfeld Oksana Seibert Daniela Strzoda Annika Zota Yvonne Feuchter Anja Krones‐Herzig Tjeerd Sijmonsma Milen Kirilov Carsten Sticht Norbert Gretz Geesje Dallinga‐Thie Sven Diederichs Nora Klöting Matthias Blüher Mauricio Berriel Diaz Stephan Herzig 《The EMBO journal》2015,34(3):344-360
In mammals, glucocorticoids (GCs) and their intracellular receptor, the glucocorticoid receptor (GR), represent critical checkpoints in the endocrine control of energy homeostasis. Indeed, aberrant GC action is linked to severe metabolic stress conditions as seen in Cushing's syndrome, GC therapy and certain components of the Metabolic Syndrome, including obesity and insulin resistance. Here, we identify the hepatic induction of the mammalian conserved microRNA (miR)‐379/410 genomic cluster as a key component of GC/GR‐driven metabolic dysfunction. Particularly, miR‐379 was up‐regulated in mouse models of hyperglucocorticoidemia and obesity as well as human liver in a GC/GR‐dependent manner. Hepatocyte‐specific silencing of miR‐379 substantially reduced circulating very‐low‐density lipoprotein (VLDL)‐associated triglyceride (TG) levels in healthy mice and normalized aberrant lipid profiles in metabolically challenged animals, mediated through miR‐379 effects on key receptors in hepatic TG re‐uptake. As hepatic miR‐379 levels were also correlated with GC and TG levels in human obese patients, the identification of a GC/GR‐controlled miRNA cluster not only defines a novel layer of hormone‐dependent metabolic control but also paves the way to alternative miRNA‐based therapeutic approaches in metabolic dysfunction. 相似文献