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11.
The detection of donor-specific anti-HLA antibodies by standard procedures such as complement-dependent cytotoxicity assay (CDC) or flow cytometric (FACS) analysis is limited by its low sensitivity and the quality of the donor cells. Therefore, an ELISA-based technique was employed using solid phase-immobilized monoclonal antibodies to capture HLA class I or class II molecules of the donor, respectively. In this HLA class I and class II antibody monitoring system (AMS) the donor-specific anti-HLA antibodies from the sera of recipients bind to the HLA molecules of the donor which have been immobilized by monoclonal antibodies (mAb) recognizing non-polymorphic epitopes. Upon binding of donor-specific anti-HLA antibodies they are recognized by secondary enzyme-conjugated anti-human immunoglobulin (Ig) antibodies. A newly established modification of the standard protocol allows the differentiation between bound antibodies of the IgG and IgM isotype. Furthermore, this assay was adapted for investigating small amounts of solid tissue of donors from whom no other cells (e.g. from blood) were available. We here provide an overview of the classical crossmatch methods with their advantages and limits. In addition, the design of the novel AMS-ELISA is described in terms of quality and sensitivity of the approach using exemplary cases of different application. The selected cases show that the AMS-ELISA represents a valuable tool for the post-transplantation monitoring of donor-specific anti-HLA antibodies during reaction crisis, after transfusion reactions and in particular cases of tissue transplantations lacking single cells. 相似文献
12.
Exonuclease 1 (Exo 1) is an important nuclease involved in mismatch repair system that contributes to maintain genomic stability,
to modulate DNA recombination, and to mediate cell cycle arrest. A guanine (G)/adenine (A) common single nucleotide polymorphism
at first position of codon 589 in Exo 1 gene determines a glutamic acid (Glu, E) to lysine (Lys, K) (K589E) aminoacidic substitution
which may alter cancer risk by influencing the activity of Exo 1 protein. Exo 1 K589E polymorphism has been studied in various
cancers, but its association with hepatocellular carcinoma (HCC) has yet to be investigated. To determine the association
of the Exo 1 K589E polymorphism with the risk of HCC development in a Turkish population, a hospital-based case–control study
was designed consisting of 224 subjects with HCC and 224 cancer-free control subjects matched for age, gender, smoking and
alcohol status. The genotype frequency of the Exo 1 K589E polymorphism was determined by using a polymerase chain reaction–restriction
fragment length polymorphism assay. Our data shows that the Lys/Lys genotype of the Exo 1 K589E polymorphism is associated
with increased risk of HCC development in this Turkish population [odds ratio (OR) = 2.15, 95% confidence interval (CI): 1.13–4.09,
P = 0.02]. Furthermore, according to stratified analysis, a significant association was observed between the homozygote Lys/Lys
genotype and HCC risk in the subgroups of male gender (OR = 2.67, 95% CI: 1.27–5.61, P = 0.009) and patients with non-viral-related HCC (OR = 3.14, 95% CI: 1.09–8.99, P = 0.03). Because our results suggest for the first time that the Lys/Lys homozygote genotype of Exo 1 K589E polymorphism
may be a genetic susceptibility factor for HCC in the Turkish population, further independent studies are required to validate
our findings in a larger series, as well as in patients of different ethnic origins. 相似文献
13.
14.
Değer Y Mert H Mert N Yur F Kozat S Yörük IH Sel T 《Biological trace element research》2008,121(1):39-43
The aim of this study was to determine the serum concentrations of selenium, vitamin E, and total- and lipid-bound sialic
acid (LBSA) in lambs with white muscle disease (WMD) before and after treatment with a commercial preparation containing selenite
and vitamin E. Fifteen lambs with WMD and ten control animals were used as research materials. Blood samples were collected
from both groups before- and 1 month after treatment for Se analysis by fluorimetry, whereas vitamin E and sialic acid were
measured by HPLC and spectrophotometry, respectively. Compared to controls, in the diseased animals, there was a significant
increase of serum total sialic acid (TSA) and LBSA, together with significant decreases of serum Se and vitamin E concentrations
(p < 0.001). One month after treatment, a reversal of trend was observed with decreases of TSA and LBSA and increases of Se
and vitamin E concentrations. The TSA and LBSA levels, however, remained significantly higher than those of the controls,
p < 0.05 and 0.001, respectively. The Se and vitamin E concentrations of the treated animals were the same as those of controls.
This is the first study on total and LBSA concentrations in lambs with WMD, showing that these markers can be used in the
prognosis of the disease. 相似文献
15.
The mast depression hypothesis (MDH) proposes that cyclic population fluctuations of microtines and other herbivores are
an effect of cyclic seed cropping of plants. This is because high seed crops, termed masts, are produced at the expense of
chemical defence against herbivores. It has generally been assumed that bird-hunting raptors produce high numbers of offspring
when microtine prey are abundant because of reduced competition from generalist predators. However, this may also be caused
by higher production of herbivorous insects, and thus insectivorous bird prey, because of lower contents of chemical defence
compounds in some plant species, such as bilberry Vaccinium myrtillus and cowberry V. vitis-idaea. In Aust-Agder county, southern Norway, the mean brood size of pied flycatcher Ficedula hypoleuca, sparrowhawk Accipiter nisus and goshawk A. gentilis was higher in peak vole years than in other years. The effect was not due to variation in nest predation, as only successful
nesting attempts were included in the analyses. For the pied flycatcher, the annual proportion of large broods (>6 fledglings)
was positively correlated with the vole trapping index. No correlation was found between the offspring production of goshawks
and the proportion of voles in their diet. During a 3-year light-trapping study of nocturnal moths prior to our study, four
moth species whose larvae ate Vaccinium were commonest in the vole peak year. All these results are consistent with the MDH.
Received: 16 March 1998 / Accepted: 20 April 1998 相似文献
16.
Robin M. Giblin-Davis Sel?uk Hazir Barbara J. Center Weimin Ye Nevin Keskin Robbin W. Thorp W. Kelley Thomas 《Journal of nematology》2005,37(3):336-342
Bursaphelenchus anatolius n. sp., a phoretic associate of Halictus bees from Ankara, Turkey, is described and illustrated. Bursaphelenchus anatolius n. sp. is closest to B. kevini, which is phoretically associated with Halictus bees from the Pacific Northwest. Bursaphelenchus anatolius n. sp. and B. kevini appear to be sister taxa based upon several shared morphological features, similar life histories involving phoresy with soil-dwelling Halictus bees, and molecular analysis of the near-full-length small subunit rDNA, D2D3 expansion segments of the large subunit rDNA, and partial mitochondrial DNA COI. Bursaphelenchus anatolius n. sp. can be differentiated from all other species of Bursaphelenchus based upon spicule morphology. The paired spicules are uniquely shaped and ventrally recurved, and both B. anatolius n. sp. and B. kevini possess extending flaps that open when the spicules are protracted beyond the cloaca. Population growth of B. anatolius n. sp. was measured at 23 °C in the laboratory on cultures of the fungus Monilinia fructicola grown on lactic acid-treated, 5% glycerol-supplemented potato dextrose agar. Nematode population densities rapidly increased from 110 to about 110,000/9-cm-diam. dish within 21 days. 相似文献
17.
Changes in the brain’s neuroactive steroid levels, behavior in the open field, and the anxious-phobic status of male and female
rats in the course of development have been studied. An increase in the motor and exploratory activity and emotionality in
rats of both sexes in the pubertal period and a decrease in their values in mature and old animals have been detected. Anxiety
has no sexual dimorphism in adult animals; it is significantly higher in males than in females in the prepubertal and pubertal
periods of development and is higher in old females than in males of the same age. An increase in the level of corticosterone
in some brain structures in maturing and old rats has been found; the testosterone concentration increases in one-month-old
and adult animals but decreases in old individuals, while the estradiol concentration in all studied brain structures of male
and female rats was low in all periods of postnatal life. Correlation analysis has shown modulation by steroid hormones of
the changes in behavioral responses during development. 相似文献
18.
The effects of timed ingestion of high-quality protein before and after resistance exercise are not well known. In this study,
young men were randomized to protein (n = 11), placebo (n = 10) and control (n = 10) groups. Muscle cross-sectional area by MRI and muscle forces were analyzed before and after 21 weeks of either heavy
resistance training (RT) or control period. Muscle biopsies were taken before, and 1 and 48 h after 5 × 10 repetition leg
press exercise (RE) as well as 21 weeks after RT. Protein (15 g of whey both before and after exercise) or non-energetic placebo
were provided to subjects in the context of both single RE bout (acute responses) as well as each RE workout twice a week
throughout the 21-week-RT. Protein intake increased (P ≤ 0.05) RT-induced muscle cross-sectional area enlargement and cell-cycle kinase cdk2 mRNA expression in the vastus lateralis
muscle suggesting higher proliferating cell activation response with protein supplementation. Moreover, protein intake seemed
to prevent 1 h post-RE decrease in myostatin and myogenin mRNA expression but did not affect activin receptor IIb, p21, FLRG,
MAFbx or MyoD expression. In conclusion, protein intake close to resistance exercise workout may alter mRNA expression in
a manner advantageous for muscle hypertrophy. 相似文献
19.