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1.
This study examines dispersions of rapeseed oil (RSO) in water by mechanical agitation under conditions mimicking those found in certain antibiotic fermentations; for example, in the presence of air, antifoam, and finely divided CaCO(3) particles. A problem with residual oil has been reported for such fermentations, and it has been suggested that the use of pre-emulsified oil can reduce this problem. Hence, the dispersion of a pre-emulsified oil produced by the "phase inversion temperature (PIT) method" has been evaluated. In both cases, the volume fraction of oil was 2%. For the RSO systems, a relatively high agitation speed was required to disperse the oil, especially in the presence of the particles and, when the agitation was stopped, separation occurred rapidly. The Sauter mean drop diameters depended on the system, being at an average energy dissipation rate of approximately 0.9 W kg(-1), 180 microm for RSO/water, 130 microm for RSO/water(antifoam)/air, 580 microm for RSO/water/CaCO(3), and 850 microm for RSO/water(antifoam)/air/CaCO(3). For the same four systems, the PIT emulsion, once dispersed, was very stable and the drop size was essentially independent of the operating conditions, with a Sauter mean diameter of approximately 0.3 microm. The implications of these findings for fermentations in which oil is used as a carbon source are assessed. 相似文献
2.
Helen K. Graham Nigel W. Hodson Judith A. Hoyland Sarah J. Millward-Sadler David Garrod Anthea Scothern Christopher E.M. Griffiths Rachel E.B. Watson Thomas R. Cox Janine T. Erler Andrew W. Trafford Michael J. Sherratt 《Matrix biology》2010,29(4):254-260
Conventional approaches for ultrastructural high-resolution imaging of biological specimens induce profound changes in bio-molecular structures. By combining tissue cryo-sectioning with non-destructive atomic force microscopy (AFM) imaging we have developed a methodology that may be applied by the non-specialist to both preserve and visualize bio-molecular structures (in particular extracellular matrix assemblies) in situ. This tissue section AFM technique is capable of: i) resolving nm–µm scale features of intra- and extracellular structures in tissue cryo-sections; ii) imaging the same tissue region before and after experimental interventions; iii) combining ultrastructural imaging with complimentary microscopical and micromechanical methods. Here, we employ this technique to: i) visualize the macro-molecular structures of unstained and unfixed fibrillar collagens (in skin, cartilage and intervertebral disc), elastic fibres (in aorta and lung), desmosomes (in nasal epithelium) and mitochondria (in heart); ii) quantify the ultrastructural effects of sequential collagenase digestion on a single elastic fibre; iii) correlate optical (auto fluorescent) with ultrastructural (AFM) images of aortic elastic lamellae. 相似文献
3.
Luciana Tovo‐Rodrigues Sidia M. Callegari‐Jacques M. Luiza Petzl‐Erler Luiza Tsuneto Francisco M. Salzano Mara H. Hutz 《American journal of physical anthropology》2010,143(3):458-464
The DRD4 variable number of tandem repeats (VNTR) allele distribution of 172 Guarani (Kaiowá and Ñandeva subgroups) and Kaingang Brazilian Amerindians is reported. These results are integrated with those previously obtained for this ethnic group. Allele frequencies for the three populations are within the interval observed for 15 other Native American populations and show intermediate values between those observed in Amazonia and Patagonia. Significant differences in allele distribution between recent past hunter–gatherer and agriculturalist populations are observed, with an increase of the 7R allele among hunter–gatherers (P < 0.001). Analysis of molecular variance (AMOVA) and pairwise FST data suggest three distinct sectors for the genetic landscape of Native South America: Andes, Center/Southeast region, and Amazonia. Common traits among hunter–gatherers such as novelty‐seeking temperament, hyperactivity, and impulsivity could have been important and advantageous in new environments during America's prehistoric colonization. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
4.
Mona Hoppenrath Malte Elbrächter Hannelore Halliger Reinoud P. T. Koeman Alexander Krakhmalnyy Barbara Surek Katrin Erler Bernd Luckas 《Helgoland Marine Research》2007,61(3):157-165
Thecadinium yashimaense was recorded for the first time in France, Great Britain, The Netherlands, and Germany. The invasion and establishment of
the species in the German Bight was documented reliably and is presented here. The geographic expansion of the species from
the North Pacific to the North Atlantic Ocean is discussed. This bloom-forming, marine, sand-dwelling dinoflagellate was shown
to be non-toxic. Also Thecadinium kofoidii, the type species of the genus, was analyzed for potential toxin production and turned out to be non-toxic as well. 相似文献
5.
Ozkinay F Ercal D Ozkinay C Onay H Bora E Erler A 《Genetic counseling (Geneva, Switzerland)》2005,16(1):45-48
Chromosome analysis in a fetus revealed an abnormal appearance of chromosome 9. The secondary constriction region of chromosome 9 was very large and two separate G+ bands were observed within this region with GTG banding. Parents' karyotypes showed maternal inheritance of this variant chromosome 9. Two G+ bands were stained negative with C banding both in the fetus and in the mother. The mother was phenotypically normal. Regarding phenotypically normal mother, normal fetal ultrasonographic findings and the similar cases described before in the literature it was considered that the fetus would be normal. Physical examination of the baby was normal after birth as expected. The existence of two G+ bands in 9qh was considered to be a normal variant in humans. 相似文献
6.
Velden J Paust HJ Hoxha E Turner JE Steinmetz OM Wolf G Jabs WJ Özcan F Beige J Heering PJ Schröder S Kneißler U Disteldorf E Mittrücker HW Stahl RA Helmchen U Panzer U 《American journal of physiology. Renal physiology》2012,302(12):F1663-F1673
Interleukin-17A (IL-17) promotes inflammatory renal tissue damage in mouse models of crescentic glomerulonephritis, including murine experimental autoimmune anti-myeloperoxidase glomerulonephritis, which most likely depends on IL-17-producing Th17 cells. In human anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis, however, the cellular sources of IL-17 remain to be elucidated. Therefore, we analyzed human kidney biopsies of active necrotizing and crescentic ANCA-associated glomerulonephritis by immunohistochemistry using an IL-17-specific antibody and by immunofluorescent colocalization with cell type markers. We detected numerous IL-17-expressing (IL-17(+)) cells in the glomeruli and in the tubulointerstitium. Unexpectedly, most of these IL-17(+) cells were polymorphonuclear neutrophilic granulocytes, while IL-17(+) T cells and IL-17(+) mast cells were present at significantly lower frequencies. IL-17 was not detected in other infiltrating or resident kidney cells. In those patients who had not received immunosuppressive treatment before biopsy, serum creatinine levels were positively correlated with tubulointerstitial IL-17(+) neutrophils as well as IL-17(+) T cells. Furthermore, we could demonstrate that purified human blood neutrophils expressed IL-17 protein and released it upon stimulation in vitro. In conclusion, these results support a pathogenic role for IL-17 in human ANCA-associated glomerulonephritis. Our data suggest that in the acute stage of the disease neutrophils may act as an important immediate-early innate source of IL-17 and may thereby initiate and promote ongoing renal inflammation. IL-17 may thus be a target for treating acute ANCA-associated glomerulonephritis. 相似文献
7.
An in-vitro model was developed to study the effects of a long-term exposure with a low concentration of ochratoxin A (OTA)
or ochratoxin C (OTC) on a human monocytic cell line (THP-1).
Cells were propagated in 24-well cell culture plates for 15 days. OTA and OTC preparations, respectively, at a concentration
of 1 ng/ml were included in the cell culture medium during the whole cultivation period. At the end of the exposure time,
parameters of cell viability and cell function were examined.
After 15 days of exposure to ochratoxins, viability and function of the THP-1 cell line were modulated. Mitochondrial activity
and the production of IL-6 were increased by all mycotoxin preparations. Cell membrane integrity was disturbed, proliferation
and the production of TNF-α and IL-8 were inhibited. These parameters were most severely affected by mycotoxin preparations
containing OTC.
Our results show that long term exposure to OTA and especially OTC in low concentrations can cause subtle alterations of cell
viability and function which may have remarkable consequences for human and animal health. In this context it seems to be
necessary to study the contamination of food and feed stuffs with OTC more intensively.
Presented at the 25th Mykotoxin Workshop in Giessen, Germany, May 19–21, 2003 相似文献
8.
Tian Xia Edward R. Horton Anna Elisabetta Salcini Roger Pocock Thomas R. Cox Janine T. Erler 《Proteomics》2018,18(2)
The nematode Caenorhabditis elegans is widely used as a model organism to study cell and developmental biology. Quantitative proteomics of C. elegans is still in its infancy and, so far, most studies have been performed on adult worm samples. Here, we used quantitative mass spectrometry to characterize protein level changes across the four larval developmental stages (L1–L4) of C. elegans. In total, we identified 4130 proteins, and quantified 1541 proteins that were present across all four stages in three biological replicates from independent experiments. Using hierarchical clustering and functional ontological analyses, we identified 21 clusters containing proteins with similar protein profiles across the four stages, and highlighted the most overrepresented biological functions in each of these protein clusters. In addition, we used the dataset to identify putative larval stage‐specific proteins in each individual developmental stage, as well as in the early and late developmental stages. In summary, this dataset provides system‐wide analysis of protein level changes across the four C. elegans larval developmental stages, which serves as a useful resource for the C. elegans research community. MS data were deposited in ProteomeXchange ( http://proteomecentral.proteomexchange.org ) via the PRIDE partner repository with the primary accession identifier PXD006676. 相似文献
9.
10.
Anke Kremp Tore Lindholm Nicole Dreßler Katrin Erler Gunnar Gerdts Sanna Eirtovaara Elina Leskinen 《Harmful algae》2009,8(2):318-328
In the past years, late summer blooms of the bioluminescent dinoflagellate Alexandrium ostenfeldii have become a recurrent phenomenon in coastal waters of the central and Northern Baltic Sea. This paper reports exceptionally high cell concentrations (105 to 106 cells L?1) of the species found during bioluminescent blooms in 2003 and 2004 in a shallow embayment of the Åland archipelago at the SW coast of Finland. Clonal cultures were established for morphological, molecular, toxicological and ecophysiological investigations to characterize the Finnish populations and compare them to other global A. ostenfeldii isolates. The Finnish isolates exhibited typical morphological features of A. ostenfeldii such as large size, a prominent ventral pore and an orthogonally bent first apical plate. However, unambiguous differentiation from closely related Alexandrium peruvianum was difficult due to considerable variation of sulcal anterior plate shapes. The Finnish strains were genetically distinct from other isolates of the species, but phylogenetic analyses revealed a close relationship to isolates from southern England and an A. peruvianum morphotype from the Spanish Mediterranean. Together these isolates formed a distinct clade which was separated from a clade containing other Northern European, North American and New Zealand populations. Toxin analyses confirmed the presence of the PSP toxins GTX2, GTX3 and STX in both Finnish isolates with GTX3 being the dominant toxin. Total relative PSP toxin contents were moderate, ranging from approximately 6 to 15 fmol cell?1 at local salinities of 5 and 10 psu, respectively. Spirolides were not detected. Salinity tolerance experiments showed that the Finnish isolates were well adapted to grow at the low salinities of the Baltic Sea. With a salinity range of approximately 6 to 20–25 psu, Baltic populations are physiologically distinct from their marine relatives. Vigorous production of different cyst types in the cultures suggest that cysts may play a crucial role in the survival and retainment of A. ostenfeldii populations in the Baltic Sea. 相似文献