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41.
Burak Derkus Kaan Cebesoy Emregul Hidayet Mazi Emel Emregul Tugrul Yumak Ali Sinag 《Bioprocess and biosystems engineering》2014,37(5):965-976
A novel highly sensitive electrochemical impedimetric Protein A immunosensor for the determination of immunoglobulin G (IgG) was developed by immobilization of Protein A within a newly synthesized, and characterized polymer, poly(maleicanhydride-alt-decene-1). TiO2 nanoparticles (10–30 nm) were synthesized, characterized with X-ray diffraction, transmission electron microscopy and Brunauer–Emmett–Teller surface analysis. The electron transfer between IgG and the poly(maleicanhydride-alt-decene-1)-TiO2-Protein A is quasireversible with a formal potential of 225 mV vs Ag|AgCl. The response of the poly(maleicanhydride-alt-decene-1)-TiO2-Protein A immunosensor was proportional to IgG concentration with a correlation coefficient of 0.9963. The detection limit and linear range was 0.57 ng mL?1 and 0.0062–500 μg mL?1, respectively. Impedance measurments showed that synthesized TiO2 nanoparticles have better conducting properties compared with commercial degussa P25 TiO2 nanoparticles. The nonspecific binding of anti-MBP was 10 %. The label-free impedimetric immunosensor provided a simple and sensitive detection method for the specific determination of IgG in human serum. 相似文献
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Arif Yuksel Levent Kebapcilar Erkan Erdur Giray Bozkaya Ismail Sari Ahmet Alacacioglu Ayse Gul Kebapcilar Gulten Sop 《Biological trace element research》2010,137(3):317-323
The present study was aimed to determine the effect of iron supplementation on levels of soluble intercellular adhesion molecule-1
(sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) in patients with iron deficiency anemia (IDA). In this study,
26 female patients diagnosed with iron deficiency were treated approximately 3 months of oral iron supplementation (99 ± 10 days;
ferrous glycine sulfate; 100 mg/day of elemental iron). Levels of sICAM-1 and sVCAM-1 were assessed prior to treatment and
after approximately 3 months of treatment and compared with 26 healthy female subjects. A significant increase in sVCAM levels
was found in the patients with iron deficiency at the end of the treatment relative to pretreatment levels compared to controls,
whereas no significant differences were determined in sICAM levels. In the posttreatment period, no significant change was
observed in sICAM levels compared to the pretreatment levels, whereas sVCAM levels decreased. However, after the treatment
period, the sVCAM, hemoglobin, mean corpuscular volume (MCV), and serum ferritin levels did not return to the normal range
compared to the controls. Pretreatment sVCAM-1 levels were inversely correlated with levels of hemoglobin, hemotocrit, MCV,
serum iron, and ferritin. After treatment, the sVCAM-1 levels were negatively correlated with ferritin levels. Levels of sVCAM
were significantly higher in patients with IDA than controls. After the treatment period, the sVCAM levels were not completely
normalized in patients with IDA compared to controls, regardless of the presence of inadequate levels of hemoglobin, MCV,
and serum ferritin. Thus, iron supplementation not only ameliorates anemia, but may also reduce the inflammation markers in
cases with IDA. 相似文献
43.
The Euglossini are a key group for studying the traits that promote or hinder highly social behavior in bees because it is
the only tribe in the Apine clade without large colonies or females with distinct life histories, e.g. queens and workers.
There have been few studies on behavior of orchid bee females in nests because these nests are not found easily. Taking advantage
of the relatively high abundance of Eg. nigropilosa nests at Reserva Natural La Planada, Colombia, we examined social behavior of Eg. nigropilosa individuals in five nests (3 original and 2 reused) for nine months. We report this species to have the largest colonies
known for Euglossa, with nests reaching up to 22 individuals, and all nests containing more than one female bee from the same generation. These
nests presented many traits that correspond to communal insect colonies. No generational overlap and no cooperative brood
care were detected. We examined natural enemies and resource limitation as important factors for group nesting. We examined
parasitoid attacks to cells in a nest with females and one without females. We also searched for nesting locations and examined
nest re-use as indicators of nest site limitation. Lastly, we examined behavioral and physiological differences among females
in the same nest. Such differences could be the bases for evolution of alternative life histories among group living females.
We examined extent of ovary development and oviposition rates in similarly aged females in the same nest. We found large variation
in reproductive effort of young females. We also examined differences in resin foraging and cell usurpation behaviors. Behavioral
specialization was observed, with some individuals bringing only resin to the nest. Inside the nests, bees had territories
in which they constructed and defended cells. This territoriality may be a defense against usurpation of provisioned cells
by nest mates.
Received 10 December 2007; revised 2 May 2008; accepted 7 May 2008. 相似文献
44.
Octopamine influences honey bee foraging preference 总被引:1,自引:0,他引:1
Colony condition and differences in individual preferences influence forage type collected by bees. Physiological bases for the changing preferences of individual foragers are just beginning to be examined. Recently, for honey bees octopamine is shown to influence age at onset of foraging and probability of dance for rewards. However, octopamine has not been causally linked with foraging preference in the field. We tested the hypothesis that changes in octopamine may alter forage type (preference hypothesis). We treated identified foragers orally with octopamine or its immediate precursor, tyramine, or sucrose syrup (control). Octopamine-treated foragers switched type of material collected; control bees did not. Tyramine group results were not different from the control group. In addition, sugar concentrations of nectar collected by foragers after octopamine treatment were lower than before treatment, indicating change in preference. In contrast, before and after nectar concentrations for bees in the control group were similar. These results, taken together, support the preference hypothesis. 相似文献
45.
Forty-seven samples of corn were collected from various street bazaars and market outlets in different regions of Turkey and
total aflatoxin (AF) and ochratoxin A (OTA) levels were determined by enzyme-linked immunosorbent assay (ELISA) following
sample preparation. Levels of AF and OTA in corn samples ranged between 1.75–120.3 μg/kg and 1.08–8.57 μg/kg, respectively.
Although 53% of the samples analysed had no detectable levels of AF, 4% of similar samples were found to contain AFs above
the acceptable limit of 10 μg/kg in Turkey. For OTA, 4% of the corn samples had levels above the acceptable limit (3 μg/kg)
in Turkey, with over 43% samples not found to contain this mycotoxin. Although the levels of mycotoxins analysed in this study
were not found to be high and the percentage of samples contaminated above permitted limits were low, the importance of overall
daily dietary intake should not be underestimated and control of these fungal metabolites in corn must be explored to minimise
the hazards they may cause in humans. 相似文献
46.
Asli Giray Kurt Emel Aytan Ufuk Ozer Burhan Ates Hikmet Geckil Professor 《Biotechnology journal》2009,4(7):1077-1088
Given the well-established beneficial effects of Vitreoscilla hemoglobin (VHb) on heterologous organisms, the potential of this protein for the production of L -DOPA and dopamine in two bacteria, Citrobacter freundii and Erwinia herbicola, was investigated. The constructed recombinants bearing the VHb gene (vgb+) had substantially higher levels of cytoplasmic L -DOPA (112 mg/L for C. freundii and 97 mg/L for E. herbicola) than their respective hosts (30.4 and 33.8 mg/L) and the vgb– control strains (35.6 and 35.8 mg/L). Further, the vgb+ recombinants of C. freundii and E. herbicola had 20-fold and about two orders of magnitude higher dopamine levels than their hosts, repectively. The activity of tyrosine phenol-lyase, the enzyme converting L -tyrosine to L -DOPA, was well-correlated to cytoplasmic L -DOPA levels. As cultures aged, higher tyrosine phenol-lyase activity of the vgb+ strains was more apparent. 相似文献
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