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1.
Dr AR Holmes RD Cannon HF Jenkinson 《Journal of industrial microbiology & biotechnology》1995,15(3):208-213
The yeastCandida albicans coaggregates with a variety of streptococcal species, an interaction that may promote oral colonization by yeast cells.C. albicans andCandida tropicalis are the yeasts most frequently isolated from the human oral cavity and our data demonstrate that both these species bind toStreptococcus gordonii NCTC 7869 while two otherCandida species (Candida krusei andCandida kefyr) do not. Adherence ofC. albicans was greatest when the yeast had been grown at 30° C to mid-exponential growth phase. For 21 strains ofC. albicans there was a positive correlation between the ability to adhere toS. gordonii and adherence to experimental salivary pellicle. Whole saliva either stimulated or slightly inhibited adherence ofC. albicans toS. gordonii depending on the streptococcal growth conditions. The results suggest that the major salivary adhesins and coaggregation adhesins ofC. albicans are co-expressed. 相似文献
2.
Abstract: Effects of cadmium (10 nM), copper (80 nM) and zinc (150 nM) additions were studied in the marine diatom Ditylum brightwellii and the riverine diatom Thalassiosira pseudonana . Defense against oxidative stress via cellular thiol (SH) pools and superoxide dismutase (SOD) activation, detoxification via phytochelatins and cell damage were monitored in metal-exposed exponential-phase cells and controls, grown in estuarine medium. Total SH and reduced + oxidized glutathione (GSH + GSSG) in T. pseudonana were much higher than in D. brightwellii . In T. pseudonana , total SH and GSH decreased at 322 nM Zn, and GSH increased at 80 nM Cu but decreased at 119 nM Cu. GSH:GSSG ratios were low, while phytochelatins were not detectable in metal-exposed D. brightwellii . Cd-exposed T. pseudonana made more phytochelatins than Cu-exposed cells, and in different proportions. At 322 nM Zn, SOD activity decreased in T. pseudonana . Zn caused a major, and Cu a minor increase of SOD activity in D. brightwellii ; inhibition of photosynthesis was observed in Cu-exposed D. brightwellii , probably due to oxidative damage. The C:N ratios were higher and protein contents lower in Cu-exposed cells of both species, which might indicate excretion due to a loss of cell membrane integrity. From these results, it is hypothesized that T. pseudonana has evolved an effective detoxification mechanism as a result of a more severe exposure to toxic metals in rivers and estuaries. In contrast, D. brightwellii , a marine-estuarine species, cannot adjust well to metal exposure. Its poor defense against metal toxicity was marked by low SH-contents. 相似文献
3.
The littoral macroalga Enteromorpha prolifera was sampled along the Scheldt estuary at Lillo (Belgium), Bath and Ellewoutsdijk (SW Netherlands). The algae were incubated in water from the same locations with salinities of 7, 14 and 23%, at about 50 molquanta m–2 s–1 irradiance and 15 °C. One series of cultures was exposed to 400 nm Cd, a second series served as a control. Temporal changes in cadmium, copper, iron, lead and zinc contents of E. prolifera were monitored with atomic absorption spectroscopy in a 21 day experiment. Both synergistic and antagonistic metal interactions became evident in response to cadmium uptake. During the first 8 days of incubation iron contents increased in both cadmium-exposed and control algae. However, iron contents were relatively higher in cadmium-exposed algae. Similar, but weaker synergisms were also found between lead/cadmium and coper/cadmium. Zinc contents decreased in controls and cadmium-exposed algae, but were significantly lower in cadmium-exposed algae. A distinct antagonism between cadmium and zinc was observed in cadmium-exposed algae. 相似文献
4.
Perni RB Pitlik J Britt SD Court JJ Courtney LF Deininger DD Farmer LJ Gates CA Harbeson SL Levin RB Lin C Lin K Moon YC Luong YP O'Malley ET Rao BG Thomson JA Tung RD Van Drie JH Wei Y 《Bioorganic & medicinal chemistry letters》2004,14(6):1441-1446
The alpha-ketoamide warhead (e.g., 15) was found to be a practical replacement for aliphatic aldehydes in a series of HCV NS3.4A protease inhibitors. Structure-activity relationships and prime side optimization are discussed. 相似文献
5.
Perni RB Britt SD Court JC Courtney LF Deininger DD Farmer LJ Gates CA Harbeson SL Kim JL Landro JA Levin RB Luong YP O'Malley ET Pitlik J Rao BG Schairer WC Thomson JA Tung RD Van Drie JH Wei Y 《Bioorganic & medicinal chemistry letters》2003,13(22):4059-4063
Tetrapeptide-based peptidomimetic compounds have been shown to effectively inhibit the hepatitis C virus NS3.4A protease without the need of a charged functionality. An aldehyde is used as a prototype reversible electrophilic warhead. The SAR of the P1 and P2 inhibitor positions is discussed. 相似文献
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Perni RB Chandorkar G Cottrell KM Gates CA Lin C Lin K Luong YP Maxwell JP Murcko MA Pitlik J Rao G Schairer WC Van Drie J Wei Y 《Bioorganic & medicinal chemistry letters》2007,17(12):3406-3411
Reversible tetrapeptide-based compounds have been shown to effectively inhibit the hepatitis C virus NS3.4A protease. Inhibition of viral replicon RNA production in Huh-7 cells has also been demonstrated. We show herein that the inclusion of hydrogen bond donors on the P4 capping group of tetrapeptide-based inhibitors result in increased binding potency to the NS3.4A protease. The capping groups also impart significant effects on the pharmacokinetic profile of these inhibitors. 相似文献
8.
Dagmar Waberski Anke Döhring Florencia Ardón Nadine Ritter Holm Zerbe Hans-Joachim Schuberth Marion Hewicker-Trautwein Karl Fritz Weitze Ronald HF Hunter 《Acta veterinaria Scandinavica》2006,48(1):13-8
Whole boar semen or seminal plasma has been demonstrated to advance the time of ovulation in gilts. As a means of clarifying
this influence, the contribution of uterine lymphatics and their white cell populations has been examined. After duct visualisation
with Evan's blue, lymph was sampled from a mesometrial vessel in eight pre-ovulatory gilts whose uterine lumen was infused
simultaneously with whole semen in one ligated horn and saline in the contralateral ligated horn. Lymph was collected from
cannulated vessels for periods of up to four hours under general anaesthesia. Thereafter, mesometrial lymph nodes, utero-tubal
junction and uterine wall tissues were sampled. The proportion of nucleated cells in the sampled lymph increased towards the
end of the collection period, but erythrocytes were found in all instances preventing a meaningful differentiation and identification
of leukocytes. Prominent uterine lymph nodes were present in the mesometrium on both sides of the reproductive tract in 7
of 10 gilts. Differences in cellular contents were demonstrated between the side of the tract infused with semen and that
infused with saline control. Two of 4 gilts had lower values for CD4 (Cluster Differentiation) and 3 of 6 gilts higher values
for MHC II (Major Histocompatibility Complex) markers on the side challenged with semen. In contrast, values remained constant
for CD8 but ranged widely for CD18. Immunohistochemical analysis of uterine tissue samples for MHC II+ cells revealed significant
differences (P < 0.05) between the control and semen-treated ligated portions of the horns, as well as between the tissue
sample of uterine wall and that from the utero-tubal junction, but there were no significant differences for CD4+ cells. It
therefore remains plausible that semen-induced cytokines in the uterine lymph undergo counter-current transfer to the ipsilateral
ovary and accelerate the final maturation of pre-ovulatory Graafian follicles. 相似文献
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Stefan Drie?en Niklas Berleth Olena Friesen Antje S L?ffler Philip B?hler Nora Hieke Fabian Stuhldreier Christoph Peter Kay O Schink Sebastian W Schultz Harald Stenmark Petter Holland Anne Simonsen Sebastian Wesselborg Bj?rn Stork 《Autophagy》2015,11(9):1458-1470
Autophagy represents an intracellular degradation process which is involved in both regular cell homeostasis and disease settings. In recent years, the molecular machinery governing this process has been elucidated. The ULK1 kinase complex consisting of the serine/threonine protein kinase ULK1 and the adapter proteins ATG13, RB1CC1, and ATG101, is centrally involved in the regulation of autophagy initiation. This complex is in turn regulated by the activity of different nutrient- or energy-sensing kinases, including MTOR, AMPK, and AKT. However, next to phosphorylation processes it has been suggested that ubiquitination of ULK1 positively influences ULK1 function. Here we report that the inhibition of deubiquitinases by the compound WP1130 leads to increased ULK1 ubiquitination, the transfer of ULK1 to aggresomes, and the inhibition of ULK1 activity. Additionally, WP1130 can block the autophagic flux. Thus, treatment with WP1130 might represent an efficient tool to inhibit the autophagy-initiating ULK1 complex and autophagy. 相似文献