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[en] Design and optimization of radioimmunoassay for T4. The results of a radioimmunoassay are influenced by the equipment, the laboratory personnel, the quality of the reagents used and especially by the assay design. A good essay design should yield analytical results with high precision and sensitivity within the desired concentration range and can be performed rapidly and easily at low cost. In order to optimize the assay design for T4 the following parameters were studied: amount and dilution of reagents, incubation temperature and length of time prior to separation, reagent volume and sequence of reagent addition. Optimal results for T4 assay were achieved using 25 ul of T4 standard (or samples), 100 ul of 125I labelled T4 (30,000 cpm) and 100 ul of T4 antiserum (1:200 dilution), incubated at room temperature for 1 hour or at 370C for 45 minutes. The following results were obtained under these conditions: a non specific binding value of (6,8+-0,7)%, a maximum binding (B/T) of (67,8+-2,2)%, a value of (5,0+-0,7)ug/dl for ED50. Results for low medium, and high quality control samples were (1,8+-0,1)ug/dl, (5,6+-0,3)ug/dl, and (14,9+-0,6)ug/dl respectively. (author). 12 figs, 6 refs
[en] In this study 233Uranyl nitrate was added to uranium (U) contaminated Hanford 300 Area sediment and incubated under moist conditions for 1 year. It hypothesized that geochemical transformations and/or physical processes will result in decreased extractability of 233U as the incubation period increases, and eventually the extraction behavior of the 233U spike will be congruent to contaminant U that has been associated with sediment for decades. Following 1 week, 1 month, and 1 year incubation periods, sediment extractions were performed using either batch or dynamic (sediment column flow) chemical extraction techniques. Overall, extraction of U from sediment using batch extraction was less complicated to conduct compared to dynamic extraction, but dynamic extraction could distinguish the range of U forms associated with sediment which are eluted at different times.
[en] Pioglitazone, a peroxisome proliferator-activated receptor gamma (PPARγ) agonist, has shown protective effects against ischemic insult in various tissues. Pioglitazone is also reported to reduce matrix metalloproteinase (MMP) activity. MMPs can remodel extracellular matrix components in many pathological conditions. The current study was designed to investigate whether the neuroprotection of pioglitazone is related to its MMP inhibition in focal cerebral ischemia. Mice were subjected to 90 min focal ischemia and reperfusion. In gel zymography, pioglitazone reduced the upregulation of active form of MMP-9 after ischemia. In in situ zymograms, pioglitazone also reduced the gelatinase activity induced by ischemia. After co-incubation with pioglitazone, in situ gelatinase activity was directly reduced. Pioglitazone reduced the infarct volume significantly compared with controls. These results demonstrate that pioglitazone may reduce MMP-9 activity and neuronal damage following focal ischemia. The reduction of MMP-9 activity may have a possible therapeutic effect for the management of brain injury after focal ischemia.
[en] The effect of irradiation of White Leghorn eggs with ultraviolet rays on their embryonal development, egg hatchability, viability of hatched chicks and their liveweight, is studied. Irradiation length was 1, 3, 5, 10, 15, 20, 40 and 60 min in two experiments and 2, 4, 16 and 256 min in one trial. It was established that egg irradiation with ultraviolet rays affected positively egg hatchability and viability of the chicks, the irradiation effect being strongest in the range of 2 to 40 min. No significant difference was established between liveweight of chicks obtained from irradiated and nonirradiated eggs. It was further found that the length of incubation period was shortened by 2 to 5 hrs with increase in irradiation length over 5 min. (author)
[en] Apparatus is described for incubating a plurality of biological samples and particularly as part of an analysis, e.g. radioimmunoassay or enzyme assay, of the samples. The apparatus is comprised of an incubation station with a plurality of containers to which samples together with diluent and reagents are supplied. The containers are arranged in rows in two side-by-side columns and are circulated sequentially. Sample removal means is provided either at a fixed location or at a movable point relative to the incubator. Circulation of the containers and the length of sample incubation time is controlled by a computer. The incubation station may include a plurality of sections with the columns in communication so that rows of samples can be moved from the column of one section to the column of an adjacent section, to provide alternative paths for circulation of the samples. (author)
[en] We underwent this study to evaluate the factors which influence labeling efficiency when modified in vivo erythrocyte labeling technique was used. Thirty healthy volunteers (M:F=19:11, age:25±2 yrs) were enrolled in this study. Totally, two hundred ten samples were obtained from them. The 1 mg of stannous pyrophosphate was injected intravenously at the beginning of labeling. After suitable tinning time (5 min, 20 min, 35 min) passed by, blood (5 mL, 3 mL or 1 mL) was withdrawn into 10 mL syringe previously containing Tc-99m (740 MBq) and anticoagulant (heparin, ACD or CPDA) through 19-gauged scalp needle. The generator ingrowth time of Tc-99m was within 24 hrs in each case. The blood samples were placed on rotating invertor during incubation (10 min, 25 min, 40 min) but some of them were not. Immediately after the conclusion of incubation, the labeled blood specimens to analyze were centrifuged and then %Unbound Tc-99m was calculated. Statical analysis was used paired T-test and one way ANOVA with SPSS 10.0. The binding efficiency at 1 mL of blood volume was 73±32%, 91±10% at 3 mL and 96±7% at 5 mL (p<0.01). The binding efficiency at 5 min of tinning time was 45±23%, 98±6% at 20 min and 97±8% at 35 min (p<0.001). The binding efficiency at 10 min of incubation time was 96±7%, 95±12% at 25 min and 98±3% at 40 min (p>0.05). The binding efficiency in case of using rotating invertor was 96±7% and the binding efficiency in case of not using it was 87±18% (p>0.05). There was no significant difference between them. In binding efficiency according to kinds of anticoagulants, ACD was 98±4%, CPDA was 97±6% and heparin was 89±20% (p<0.001). When modified in vivo erythrocyte labeling technique is used with Tc-99m, the methods to obtain the highest labeling efficiency are as follow. The withdrawing blood volume should be over 3 mL, tinning time should be kept between 20 min and 35 min, and incubation time should be kept between 10 min and 40 min. ACD or CPDA have to be used as a anticoagulant except heparin and the blood samples should be placed on rotating invertor during incubation
[en] 99mTc-rufloxacin (99mTc-RUN) complex was prepared by reaction of different amounts of reduced sodium pertechnetate with different amount of Rufloxacin (RUN) antibiotic for the in vivo scintigraphic localization of the Staphylococcus aureus (S. aureus) infectious foci in Male Wister Rats (MWR) model. The 99mTc-RUN complex was radiochemically and biologically characterized in terms of radiochemical stability in saline, serum, in vitro binding with S. aureus and biodistribution in artificially infected with S. aureus MWR. The 99mTc-RUN complex showed stability more than 90% up to 240 min in normal saline with a maximum stability value of 98.10 ± 0.18% at 30 min after reconstitution. At 37 deg C the complex showed in vitro permanence in serum up to 16 h with 13.90% side products during incubation. The 99mTc-RUN complex showed saturated in vitro binding with S. aureus at different intervals with a maximum uptake value of 71.50%. Infected to normal muscle, infected to inflamed and inflamed to normal muscles ratios were approximately 6.04, 4.31 and 1.40. Based on the stability of the complex in saline, serum, in vitro binding with S. aureus and biodistribution results, the 99mTc-RUN complex is recommended for in vivo scintigraphic localization of the S. aureus in vivo infectious foci in human. (author)
[en] Nine fungal strains related to: Trametes versicolor, Nigrospora oryzae, Inonotus radiatus, Crumenulopsis sororia, Coryneum betulinum, Cryptosporiopsis radicicola, Fusarium equiseti, Rhodotorula glutinis and Candida parapsilosis were tested for their ability to degrade humulones and lupulones. The best results were obtained for T. versicolor culture, in which humulones and lupulones were fully degraded after 4 days of incubation in the dark or after 36 h in the light. The experiments were performed on a commercial hop extract and on sterilized spent hops
[en] We wanted to know if incubation time and temperature for many radioimmunoassay methods could be standardized, to decrease assay time and so improve efficiency. Percentage binding was determined for triiodothyronine, thyroxine, digoxin, digitoxin, testosterone, aldosterone, estradiol, and diphenylhydantoin when the reaction mixtures were incubated at 6 to 8, 22, or 370C for various periods of time. In all methods tested, binding of antigen to antibody was greatest when the reaction mixtures were incubated at 6 to 80C, less at 220C, and least at 370C. Maximum binding occurred within 30 to 60 min at each temperature for all methods tested. Hence, it is possible to standardize the incubation time and temperature for these eight radioimmunoassay methods to 60 min at 6 to 80C