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71.
Pascal Bonnarme Michel Delattre Georges Corrieu Marcel Asther 《Applied microbiology and biotechnology》1992,37(5):670-673
Summary Lignin (LiP) and manganese peroxidase (MnP) excretion by Phanerochaete chrysosporium INA-12 was significantly increased in response to fungal extract supplementation. LiP and MnP production was increased 1.7- and 1.8-fold, respectively, with fungal extracts from agitated pellet cultures of strain INA-12, namely fungal extracts P6 and P4. In cultures supplemented with a fungal extract harvested from static cultures of strain INA-12 (fungal extract S4), LiP and MnP production was increased 1.8- and 1.6-fold, respectively. Succinate dehydrogenase activity, a mitochondrial marker, was significantly enhanced (2.7-fold) in cultures with the addition of fungal extracts.
Correspondence to: M. Asther 相似文献
72.
Frederick C. Wedler Michael C. Vichnin Brenda W. Ley Georges Tholey Marc Ledig Jean-Christoph Copin 《Neurochemical research》1994,19(2):145-151
Previous studies have demonstrated that in glia and astrocytes Mn(II) is distributed with ca. 30–40% in the cytoplasm, 60–70% in mitochondria. Ca(II) ions were observed to alter both the flux rates and distribution of Mn(II) ions in primary cultues of chick glia and rat astrocytes. External (influxing) Ca(II) ions had the greatest effect on Mn(II) uptake and efflux, compared to internal (effluxing) or internal-external equilibrated Ca(II) ions. External (influxing) Ca(II) ions inhibited the net rate and extent of Mn(II) uptake but enhanced Mn(II) efflux from mitochondria. These observations differ from Ca(II)–Mn(II) effects previously reported with brain (neuronal) mitochondria. Overall, increased cytoplasmic Ca(II) acts to block Mn(II) uptake and enhance Mn(II) release by mitochondria, which serve to increase the cytoplasmic concentration of free Mn(II). A hypothesis is presented involving external L-glutamate acting through membrane receptors to mobilize cell Ca(II), which in turn causes mitochondrial Mn(II) to be released. Because the concentration of free cytoplasmic Mn(II) is poised near the Kd for Mn(II) with glutamine synthetase, a slight increase in cytoplasmic Mn(II) will directly enhance the activity of glutamine synthetase, which catalyzes removal of neurotoxic glutamate and ammonia. 相似文献
73.
To meet the technical challenge of recovering human IgG fusion protein from transgenic whole goat milk at reasonable cost with high purity and yield, a predictive aggregate transport model for microfiltration has been developed (Baruah and Belfort, 2003). Here, to test the model's predictability of permeate flux and mass transport, a comprehensive series of experiments with varying wall shear rate, feed temperature, feed concentration, and module design are presented. A very good fit was obtained between the model predictions and measurements for a wide variety of experimental conditions. For microfiltration module design comparison, a linear hollow fiber module (representing current commercial technologies) gave lower permeation flux and higher yield than a helical hollow fiber module (representing the latest self-cleaning methodology). These results are easily explained with the model that is now being used to define operating conditions for maximizing performance. The procedure described by the model is generalizable and can be used to obtain optimal filtration performance for applications other than milk. 相似文献
74.
Rhodobacter sphaeroides is able to assemble two different flagella, the subpolar flagellum (Fla1) and the polar flagella (Fla2). In this work, we report the swimming behavior of R. sphaeroides Fla2(+) cells lacking each of the proteins encoded by chemotactic operon 1. A model proposing how these proteins control Fla2 rotation is presented. 相似文献
75.
Objectives
There has been increased interest in the possible role of human cytomegalovirus (HCMV) in carcinogenesis during the last decade. HCMV seroprevalence was enhanced in patients with hepatocellular carcinoma (HCC) but a possible relationship between HCC and HCMV infection remained to be assessed. The aim of this work was to investigate the pro-tumor influence of HCMV on primary human hepatocytes (PHH) and HepG2 cells.Methods
Following infection of PHH and HepG2 cells by two different strains of HCMV, we measured the production of IL-6 in culture supernatants by ELISA and the protein levels of STAT3, pSTAT3, JAK, cyclin D1, survivin, p53, p21, and Mdm2 by western Blotting in infected and uninfected cells. Cell proliferation and transformation were investigated using Ki67Ag expression measurement and soft-agar colony formation assay respectively.Results
Infection of HepG2 cells and PHH by HCMV resulted in the production of IL-6 and the subsequent activation of the IL-6R-JAK-STAT3 pathway. HCMV increased the expression of cyclin D1 and survivin. Cell proliferation was enhanced in HepG2 and PHH infected with HCMV, despite a paradoxical overexpression of p53 and p21. More importantly, we observed the formation of colonies in soft agar seeded with PHH infected with HCMV and when we challenged the HepG2 cultures to form tumorspheres, we found that the HCMV-infected cultures formed 2.5-fold more tumorspheres than uninfected cultures.Conclusion
HCMV activated the IL-6-JAK-STAT3 pathway in PHH and HepG2 cells, favored cellular proliferation, induced PHH transformation and enhanced HepG2 tumorsphere formation. Our observations raise the possibility that HCMV infection might be involved in the genesis of hepatocellular carcinoma. 相似文献76.
Thomas?Durand Sophie?Jacob Laura?Lebouil Hassen?Douzane Philippe?Lestaevel Amithys?Rahimian Dimitri?Psimaras Lo?c?Feuvret Delphine?Leclercq Bruno?Brochet Radia?Tamarat Fabien?Milliat Marc?Benderitter Nicolas?Vayatis Georges?No?l Khê?Hoang-Xuan Jean-Yves?Delattre Damien?Ricard Marie-Odile?BernierEmail author 《BMC neurology》2015,15(1):261
Background
Radiotherapy is one of the most important treatments of primary and metastatic brain tumors. Unfortunately, it can involve moderate to severe complications among which leukoencephalopathy is very frequent and implies cognitive deficits such as memory, attention and executive dysfunctions. However, the incidence of this complication is not well established and the risk factors and process are poorly understood. The main objective of the study is to improve knowledge on radio-induced leukoencephalopathy based on pluridisciplinar approaches combining cognitive, biologic, imagery and dosimetric investigations.Method/Design
The EpiBrainRad study is a prospective cohort study including newly diagnosed high grade gliomas patients treated by radiotherapy and concomitant-adjuvant temozolomide chemotherapy. Patients are included between their surgery and first day of radio-chemotherapy, and the follow-up lasts for 3 years after treatment. Cognitive functioning assessments, specific blood biomarkers measures and magnetic resonance imagery are performed at different moment during the follow-up, and a specific dosimetric assessment of organs involved in the beam fields is performed. Firstly, leukoencephalopathy incidence rate will be estimated in this population. Secondly, correlations between cognitive impairments and dosimetry, biomarkers ranges and anomalies on imagery will be analyzed in order to better understand the onset and evolution of cognitive decrement associated with radiotherapy. Furthermore, a new cognitive test, quickly and easily performed, will be studied to determine its sensibility to detect leukoencephalopathy decrement.Discussion
With an original multidisciplinary approach, the EpiBrainRad study aims to improve knowledge on radio-induced leukoencephalopathy in order to improve its early diagnosis and prevention. The main challenge is to preserve quality-of-life after cancer treatments which imply to study the incidence of radiation-induced complications and their associated risk factors.Trial Registration
NCT0254417877.
78.
Tariq Ezaz Denis O’Meally Alexander E. Quinn Stephen D. Sarre Arthur Georges Jennifer A. Marshall Graves 《Cytotechnology》2008,58(3):135-139
Primary cell lines were established from cultures of tail and toe clips of five species of Australian dragon lizards: Tympanocryptis pinguicolla, Tympanocryptis sp., Ctenophorus fordi, Amphibolurus norrisi and Pogona vitticeps. The start of exponential cell growth ranged from 1 to 5 weeks. Cultures from all specimens had fibroblastic morphology.
Cell lines were propagated continuously up to ten passages, cryopreserved and recovered successfully. We found no reduction
in cell viability after short term (<6 months) storage at −80 °C. Mitotic metaphase chromosomes were harvested from these
cell lines and used in differential staining, banding and fluorescent in situ hybridisation. Cell lines maintained normal
diploidy in all species. This study reports a simple non-invasive method for establishing primary cell lines from Australian
dragon lizards without sacrifice. The method is likely to be applicable to a range of species. Such cell lines provide a virtually
unlimited source of material for cytogenetic, evolutionary and genomic studies. 相似文献
79.
80.
Véronique de Berardinis David Vallenet Vanina Castelli Marielle Besnard Agnès Pinet Corinne Cruaud Sumitta Samair Christophe Lechaplais Gabor Gyapay Céline Richez Maxime Durot Annett Kreimeyer François Le Fèvre Vincent Schächter Valérie Pezo Volker Döring Claude Scarpelli Claudine Médigue Georges N Cohen Philippe Marlière Marcel Salanoubat Jean Weissenbach 《Molecular systems biology》2008,4(1)
We have constructed a collection of single‐gene deletion mutants for all dispensable genes of the soil bacterium Acinetobacter baylyi ADP1. A total of 2594 deletion mutants were obtained, whereas 499 (16%) were not, and are therefore candidate essential genes for life on minimal medium. This essentiality data set is 88% consistent with the Escherichia coli data set inferred from the Keio mutant collection profiled for growth on minimal medium, while 80% of the orthologous genes described as essential in Pseudomonas aeruginosa are also essential in ADP1. Several strategies were undertaken to investigate ADP1 metabolism by (1) searching for discrepancies between our essentiality data and current metabolic knowledge, (2) comparing this essentiality data set to those from other organisms, (3) systematic phenotyping of the mutant collection on a variety of carbon sources (quinate, 2‐3 butanediol, glucose, etc.). This collection provides a new resource for the study of gene function by forward and reverse genetic approaches and constitutes a robust experimental data source for systems biology approaches. 相似文献