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111.
Caffeic acid phenethyl ester (CAPE), a flavonoid like compound, is one of the major components of honeybee propolis. It has been used in folk medicine for many years in Middle East countries. It was found to be a potent free radical scavenger and antioxidant recently. The aim of this study was to examine long-term applied 900 MHz emitting mobile phone-induced oxidative stress that promotes production of reactive oxygen species (ROS) and, was to investigate the role of CAPE on kidney tissue against the possible electromagnetic radiation (EMR)-induced renal impairment in rats. In particular, the ROS such as superoxide and nitric oxide (NO) may contribute to the pathophysiology of EMR-induced renal impairment. Malondialdehyde (MDA, an index of lipid peroxidation) levels, urinary N-acetyl-β-d-glucosaminidase (NAG, a marker of renal tubular injury) and nitric oxide (NO, an oxidant product) levels were used as markers of oxidative stress-induced renal impairment and the success of CAPE treatment. The activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in renal tissue were determined to evaluate the changes of antioxidant status. The rats used in the study were randomly grouped (10 each) as follows: i) Control group (without stress and EMR), ii) Sham-operated rats stayed without exposure to EMR (exposure device off), iii) Rats exposed to 900 MHz EMR (EMR group), and iv) A 900 MHz EMR exposed + CAPE treated group (EMR + CAPE group). In the EMR exposed group, while tissue MDA, NO levels and urinary NAG levels increased (p < 0.0001), the activities of SOD, CAT, and GSH-Px in renal tissue were reduced (p < 0.001). CAPE treatment reversed these effects as well (p < 0.0001, p < 0.001 respectively). In conclusion, the increase in NO and MDA levels of renal tissue, and in urinary NAG with the decrease in renal SOD, CAT, GSH-Px activities demonstrate the role of oxidative mechanisms in 900 MHz mobile phone-induced renal tissue damage, and CAPE, via its free radical scavenging and antioxidant properties, ameliorates oxidative renal damage. These results strongly suggest that CAPE exhibits a protective effect on mobile phone-induced and free radical mediated oxidative renal impairment in rats.  相似文献   
112.
In this study, acetylcholinesterase and choline oxidase were co-immobilized on poly(2-hydroxyethyl methacrylate) membranes and the change in oxygen consumption upon aldicarb introduction was measured. Immobilization of the enzymes was achieved either by entrapment or by surface attachment via a hybrid immobilization method including epichlorohydrin and Cibacron Blue F36A activation. Immobilized enzymes had a long-storage stability (only 15% activity decrease in 2 months in wet storage and no activity loss in dry storage). Aldicarb detection studies showed that a linear working range of 10-500 and 10-250 ppb aldicarb could be achieved by entrapped and surface immobilized enzymes, respectively. Enzymes immobilized on membrane surfaces responded to aldicarb presence more quickly than entrapped enzymes. Aldicarb concentrations as low as 23 and 12 ppb could be detected by entrapped and surface immobilized enzymes, respectively, in 25 min.  相似文献   
113.
Five chimpanzees were immunized by administration of one or more intranasal priming doses of one to three recombinant adenoviruses containing a gp160 insert from human immunodeficiency virus type 1 (HIV-1) MN (HIV-1MN) followed by one or more boosts of recombinant HIV-1SF2 gp120 delivered intramuscularly with MF59 adjuvant. This regimen resulted in humoral immune responses in three of five animals. Humoral responses included immunochemically active anti-HIV-1 antibodies (Abs) directed to recombinant gp120 and neutralizing Abs reactive with T-cell-line-adapted HIV-1MN and HIV-1SF2. In addition, neutralizing activity was detected to the two homologous primary isolates and to two of three heterologous primary isolates which, like the immunizing strains, can use CXCR4 as a coreceptor for infection. The three animals with detectable neutralizing Abs and a fourth exhibiting the best cytotoxic T-lymphocyte response were protected from a low-dose intravenous challenge with a cell-free HIV-1SF2 primary isolate administered 4 weeks after the last boost. Animals were rested for 46 weeks and then rechallenged, without a boost, with an eightfold-higher challenge dose of HIV-1SF2. The three animals with persistent neutralizing Abs were again protected. These data show that a strong, long-lived protective Ab response can be induced with a prime-boost regimen in chimpanzees. The data suggest that in chimpanzees, the presence of neutralizing Abs correlates with protection for animals challenged intravenously with a high dose of a homologous strain of HIV-1, and they demonstrate for the first time the induction of neutralizing Abs to homologous and heterologous primary isolates.  相似文献   
114.
The reaction of vitamin B12r, generated by photolysis of methylcobalamin under a nitrogen atmosphere, with 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT), results in extensive dechlorination and formation of 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD) and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) as the major products. Minor quantities of 1,1-bis(p-chlorophenyl)-2-chloroethane (DDMS), 1,1-bis(p-chlorophenyl)-2-chloroethylene (DDMU), 1,1-bis(p-chlorophenyl)ethane (DDO), and 1,1-bis(p-chlorophenyl)ethylene (DDNU) were also formed. Reaction of vitamin B12r with DDD results in the production of DDMU and DDMS, the latter of which can react to produce DDNU and DDO. DDE and DDMU do not react with vitamin B12r. The results obtained are suggestive of a vitamin B12r-mediated dechlorination pathway for polyhalogenated hydrocarbon pesticides.  相似文献   
115.
There are contradictory results in the literature relating to the effect oftamoxifen on membrane fluidity. The present work investigates the effect oftamoxifen on membrane dynamics to find out whether the concentration oftamoxifen can be one of the factors in this discrepancy. Turbidity(absorbance at 440 nm) and Fourier transform infrared spectroscopicstudies reveal that tamoxifen causes opposite effects on membranefluidity at low (1 mol.%) and high (30 mol.%) tamoxifen concentrations. Lowtamoxifen concentrations increase the absorbance in the gel and liquidcrystalline phase, whereas high tamoxifen concentrations decrease theabsorbance in gel and liquid crystalline phase, whereas tamoxifenconcentrations decrease the absorbance. Observations on both phasesshow that the bandwidth of the CH2 stretching bands decreases with1 mol.% tamoxifen and increases with 30 mol.% tamoxifen present, indicatinga decrease in membrane fluidity at low tamoxifen concentrations and anincrease in fluidity at high tamoxifen concentrations. It is seen that theapparent discrepancy in the literature on the effect of tamoxifen onmembrane fluidity mainly arises from the tamoxifen concentration used andthe confusion on the concept of lipid fluidity and lipid order.  相似文献   
116.
The present study aims to examine the changes in the serum levels of trace elements before and after the operation in thyroid cancer patients. The study registered 50 individuals, of whom 25 were female and 25 were male. The patients were allocated to four groups: group 1: male thyroid cancer patients group (n = 15), group 2: female thyroid cancer patients group (n = 15), group 3: male control group (n = 10), group 4: female control group (n = 10). The subjects in groups 1 and 2 were the patients who were post-operatively diagnosed with a pathological malignancy in the thyroid tissue samples. Blood samples were collected from all subjects before the operation, immediately after the operation, and on the post-operative day 15. Additionally, thyroid tissue samples were taken from all subjects post-operatively. Some elements in the blood and tissue samples were determined using the atomic emission method. Zinc and selenium levels of groups 1 and 2 in the pre- and post-operative measurements were significantly lower than those in the control groups (p < 0.05), but were higher in the thyroid tissue (p < 0.05). Serum zinc and selenium levels measured in the subjects on the post-operative day 15 were similar to those measured in the controls. Our study show that changes in the serum and thyroid tissue levels of trace elements like zinc and selenium, which play a critical role in thyroid function, might be associated with the pathogenesis of thyroid cancer.  相似文献   
117.
In light of our ageing population it is important that the urban environment is easily accessible and hence supports older adults' independence. Tactile 'blister' paving was originally designed to provide guidance for visually impaired people at pedestrian crossings. However, as research links irregular surfaces to falls in older adults, such paving may have an adverse effect on older people. We investigated the effects of tactile paving on older adults' gait in a scenario closely resembling crossing the street. Gait analysis of 32 healthy older adults showed that tactile, as compared to smooth, paving increases the variability in timing of foot placement by 20%, thereby indicating a disturbance of the rhythmic gait pattern. Moreover, toe clearance during the swing phase increased by 7% on tactile paving, and the ability to stop upon cue from the traffic light was compromised. These results need to be viewed under the consideration of limitations associated with laboratory studies and real world analysis is needed to fully understand their implications for urban design.  相似文献   
118.
IL-26 is classified as a member of the IL-10 cytokine family because it has limited sequence homology to IL-10 and the IL-10-related cytokines. The human IL-26 gene, IL26, is located on chromosome 12q15 between the genes for two other important class-2 cytokines, IFNG (IFN-γ) and IL22 (IL-22). IL-26 is often co-expressed with IL-22 by activated T cells, especially Th17 cells. It signals through a heterodimeric receptor complex composed of the IL-20R1 and IL-10R2 chains. IL-26 receptors are primarily expressed on non-hematopoietic cell types, particularly epithelial cells. Signaling through IL-26 receptor complexes results in the activation of STAT1 and STAT3 with subsequent induction of IL-26-responsive genes. The biological functions of IL-26 have only begun to be defined.  相似文献   
119.
Sarcoidosis is a chronic inflammatory disease with a complex pathogenesis and unknown etiology characterized by noncaseating granulomas that invade the lungs, eyes, liver and other organs. Insertion (I)/deletion (D) polymorphism in the gene encoding the angiotensin-converting enzyme (ACE) has been studied to examine the genetic predisposition to sarcoidosis in different populations, but the results have been inconsistent and inconclusive. This study aimed to determine the frequencies of the genotypes and alleles of I/D polymorphism in the ACE gene in Turkish patients as a distinct ethnic group and to investigate whether such polymorphism is associated with predisposition to sarcoidosis. Genomic DNA samples obtained from 154 individuals (70 patients with sarcoidosis and 84 healthy controls) were used in the study. The DNA was amplified using polymerase chain reactions using allele-specific primers. The amplified products were analyzed by 2 % agarose gel electrophoresis followed by UV transillumination. The allele frequencies and genotype distribution of the groups were analyzed using the Chi square test. There were no significant differences between the controls and sarcoidosis cases with respect to genotype distribution (χ2 = 4.202, p = 0.122) and allele frequencies (χ2 = 1.358, p = 0.244). Our results suggest that I/D polymorphism in the ACE gene does not cause a genetic predisposition to sarcoidosis in Turkish patients.  相似文献   
120.
Summary A decondensed site at band q26 of the X chromosome was found in a male baby with growth and developmental retardation and a dysmorphic syndrome, as well as in his phenotypically normal mother, without using any special culture conditions.  相似文献   
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