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1.
FURTHER STUDIES ON MOBILIZATION OF CFUs 总被引:1,自引:0,他引:1
Mobilization of CFUs from haemopoietic tissues into circulation was studied after injection of different bacterial lipopolysaccharides (LPS), zymosan, phytohaemagglutinin (PHA), concanavalin A (Con A), trypsin and di-isopropyl-fluorophosphate-inhibited trypsin. All bacterial LPS used gave an increase of CFUs in the peripheral blood at 1 h after i.v. injection. Some variation in activity could not be excluded. As with Salmonella typhosa LPS, zymosan gave an increase in circulating CFUs during the first few hr and a second peak a few days later. After injection of zymosan as well as S. typhosa LPS the second peak in the blood was accompanied by a large increase in CFUs numbers in the spleen. PHA gave an immediate mobilization of CFUs, but the mobilization after injection of Con A during the first few hr occurred more slowly. After injection of S. typhosa LPS, zymosan and PHA the blood C3 level was found to be depressed considerably. This might indicate that the complement system is involved in the early mobilization of CFUs. Dexamethasone, a synthetic hormone which has been reported to give sequestration of several cell types in the bone marrow, did not inhibit the early and late mobilization of CFUs which normally occurs after injection of S. typhosa LPS. 相似文献
2.
Smith I Broos A de Jong C Zeddeman A Smith C Smith G Moore F Barr J Crameri G Marsh G Tachedjian M Yu M Kung YH Wang LF Field H 《PloS one》2011,6(9):e25275
Hendra virus (HeV) causes a zoonotic disease with high mortality that is transmitted to humans from bats of the genus Pteropus (flying foxes) via an intermediary equine host. Factors promoting spillover from bats to horses are uncertain at this time, but plausibly encompass host and/or agent and/or environmental factors. There is a lack of HeV sequence information derived from the natural bat host, as previously sequences have only been obtained from horses or humans following spillover events. In order to obtain an insight into possible variants of HeV circulating in flying foxes, collection of urine was undertaken in multiple flying fox roosts in Queensland, Australia. HeV was found to be geographically widespread in flying foxes with a number of HeV variants circulating at the one time at multiple locations, while at times the same variant was found circulating at disparate locations. Sequence diversity within variants allowed differentiation on the basis of nucleotide changes, and hypervariable regions in the genome were identified that could be used to differentiate circulating variants. Further, during the study, HeV was isolated from the urine of flying foxes on four occasions from three different locations. The data indicates that spillover events do not correlate with particular HeV isolates, suggesting that host and/or environmental factors are the primary determinants of bat-horse spillover. Thus future spillover events are likely to occur, and there is an on-going need for effective risk management strategies for both human and animal health. 相似文献
3.
Diagnostic polymorphisms in the mitochondrial cytochrome b gene allow discrimination between cattle,sheep, goat,roe buck and deer by PCR-RFLP 总被引:3,自引:0,他引:3
Background
As an alternative to direct DNA sequencing of PCR products, random PCR-RFLP is an efficient technique to discriminate between species. The PCR-RFLP-method is an inexpensive tool in forensic science, even if the template is degraded or contains only traces of DNA from various species. 相似文献4.
5.
Neiman M Hedberg JJ Dönnes PR Schuppe-Koistinen I Hanschke S Schindler R Uhlén M Schwenk JM Nilsson P 《Journal of proteome research》2011,10(11):4925-4934
There is a need for reliable and sensitive biomarkers for renal impairments to detect early signs of kidney toxicity and to monitor progression of disease. Here, antibody suspension bead arrays were applied to profile plasma samples from patients with four types of kidney disorders: glomerulonephritis, diabetic nephropathy, obstructive uropathy, and analgesic abuse. In total, 200 clinical renal-associated cases and control plasma samples from different cohorts were profiled. Parallel plasma protein profiles were obtained using biotinylated and nonfractionated samples and a selected set of 94 proteins targeted by 129 antigen-purified polyclonal antibodies. Out of the analyzed target proteins, human fibulin-1 was detected at significantly higher levels in the glomerulonephritis patient group compared to the controls and with elevated levels in patient samples for all other renal disorders investigated. Two polyclonal antibodies and one monoclonal antibody directed toward separate, nonoverlapping epitopes showed the same trend in the discovery cohorts. A technical verification using Western blot analysis of selected patient plasma confirmed the trends toward higher abundance of the target protein in disease samples. Furthermore, a verification study was carried out in the context of glomerulonephritis using an independent case and control cohort, and this confirmed the results from the discovery cohort, suggesting that plasma levels of fibulin-1 could serve as a potential indicator to monitor kidney malfunction or kidney damage. 相似文献
6.
Thioesterase activity and acyl-CoA/fatty acid cross-talk of hepatocyte nuclear factor-4{alpha} 总被引:2,自引:0,他引:2
Hertz R Kalderon B Byk T Berman I Za'tara G Mayer R Bar-Tana J 《The Journal of biological chemistry》2005,280(26):24451-24461
7.
Plant regeneration from Rosa shoot tips cryopreserved by a combined droplet vitrification method 总被引:1,自引:0,他引:1
Shoot tips obtained from in vitro Rosa plants (three cultivars) were successfully cryopreserved by a combined droplet vitrification method and subsequently shoots
regenerated. The excised shoot tips (1–4 mm long) were incubated in a liquid MS medium supplemented with 2.5 mg l−1 thiamine, 0.2 mg l−1 biotin, 0.2 mg l−1 pyridoxine, 0.25 mg l−1 6-benzylaminopurine (BAP), 0.5 mg l−1 gibberellic acid (GA3) and 0.08 M sucrose, for 24 h. Following that incubation shoot tips were pre-cultured in this MS medium containing 0.1 till
1.0 M sucrose for 24 and 48 h, respectively. Pre-cultured shoot tips were dehydrated with concentrated PVS2 cryoprotective
solution for 10–30 min at room temperature, prior to a direct plunge in liquid nitrogen. After rapid rewarming in the above
mentioned liquid medium shoot tips were plated on a modified MS medium (5 g l−1 agar) supplemented with vitamins and plant growth regulators as mentioned above for regrowth. Cryopreserved shoot tips resumed
growth within 10 days and regenerated shoots within 3 weeks. The highest numbers of regrowing shoot tips were 64.44% for cv.
Kardinal, 67.73% for cv. Fairy and 57.57% for cv. Maidy. 相似文献
8.
Kazuo Ina Reiko Takasawa Akihito Yagi Noriyuki Yamashita Hideo Ltoh Kanzo Sakata 《Bioscience, biotechnology, and biochemistry》2013,77(12):3319-3321
The restriction endonuclease AatII was purified from cell-free extracts of Acetobacter aceti IFO 3281 by streptomycin treatment, ammonium sulfate fractionation, combined column chromatographies on DEAE-Toyopearl 650S, heparin-Sepharose CL-6B and DEAE-Sepharose CL-6B and FPLC on Mono Q and on Superose 12 (gel filtration). The purified enzyme was homogeneous on SDS-polyacrylamide gel disk electrophoresis. The relative molecular mass of the purified enzyme was 190,000 daltons by gel filtration. The SDS-polyacrylamide gel disk electrophoresis gave the relative molecular mass of 47,500 daltons. These data indicated that the purified, native enzyme is a tetramer (190,000 daltons) composed of four 47,500-dalton subunits. The isoelectric point of the enzyme was 6.0. The purified enzyme was intensely activated by manganese ion (50-fold increase or more when compared with magnesium ion). The enzyme worked best at 37°C and pH 8.5 in a reaction mixture (50 μl) containing 1.0 μg λDNA, 10 mm Tris-HCl, 7 mm 2-mercaptoethanol, 7 mm MnCl2 and 50 mm NaCl. The enzyme recognizes the same palindromic hexanucleotide sequence 5′-GACGTC-3′, cuts between T and C and produces a 3′-tetranucleotide extension in the presence of MnCl2, as it does in the presence of MgCl2. 相似文献
9.
Katja Behnke Maaria Loivamäki Ina Zimmer Heinz Rennenberg Jörg-Peter Schnitzler Sandrine Louis 《Photosynthesis research》2010,104(1):5-17
In the present study, we combined transient temperature and light stress (sunfleck) and comparably analyzed photosynthetic
gas exchange in Grey poplar which has been genetically modified in isoprene emission capacity. Overall, we demonstrate that
for poplar leaves the ability to emit isoprene is crucial to maintain photosynthesis when exposed to sunflecks. Net CO2 assimilation and electron transport rates were strongly impaired in sunfleck-treated non-isoprene emitting poplars. Similar
impairment was not detected when the leaves were exposed to high light (lightflecks) only. Within 10 h non-isoprene emitting
poplars recovered from sunfleck-related impairment as indicated by chlorophyll fluorescence and microarray analysis. Unstressed
leaves of non-isoprene emitting poplars had higher ascorbate contents, but also higher contents of malondialdehyde than wild-type.
Microarray analyses revealed lipid and chlorophyll degradation processes in the non-isoprene emitting poplars. Thus, there
is evidence for an adjustment of the antioxidative system in the non-isoprene emitting poplars even under normal growth conditions. 相似文献
10.