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111.
Electroconvulsive therapy (ECT) remains one of the most effective treatments of major depression. It has been suggested that the mechanisms of action involve gene expression. In recent decades there have been several investigations of gene expression following both acute and chronic electroconvulsive stimulation (ECS). These studies have focused on several distinct gene targets but have generally included only few time points after ECS for measuring gene expression. Here we measured gene expression of three types of genes: Immediate early genes, synaptic proteins, and neuropeptides at six time points following an acute ECS. We find significant increases for c-Fos, Egr1, Neuritin 1 (Nrn 1), Bdnf, Snap29, Synaptotagmin III (Syt 3), Synapsin I (Syn 1), and Psd95 at differing time points after ECS. For some genes these changes are prolonged whereas for others they are transient. Npy expression significantly increases whereas the gene expression of its receptors Npy1r, Npy2r, and Npy5r initially decreases. These decreases are followed by a significant increase for Npy2r, suggesting anticonvulsive adaptations following seizures. In summary, we find distinct changes in mRNA quantities that are characteristic for each gene. Considering the observed transitory and inverse changes in expression patterns, these data underline the importance of conducting measurements at several time points post-ECS. 相似文献
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Maria Kippler Karin Engstr?m Simona Jurkovic Mlakar Matteo Bottai Sultan Ahmed Mohammad Bakhtiar Hossain Rubhana Raqib Marie Vahter Karin Broberg 《Epigenetics》2013,8(5):494-503
Dietary cadmium exposure was recently found to alter DNA methylation in adults, but data on effects early in life are lacking. Our objective was to evaluate associations between prenatal cadmium exposure, DNA methylation and birth weight. In total 127 mother-child pairs from rural Bangladesh were studied. For comparison, we included 56 children at 4.5 y. Cadmium concentrations in mothers’ blood (gestational week 14) and children’s urine were measured by ICPMS. Global DNA methylation was analyzed by Infinium HumanMethylation450K BeadChip in cord blood and children’s blood. Maternal cadmium exposure was associated with cord blood DNA methylation (p-value < 10–16). The association was markedly sex-specific. In boys, 96% of the top 500 CpG sites showed positive correlations (rS-values > 0.50), whereas most associations in girls were inverse; only 29% were positive (rS > 0.45). In girls we found overrepresentation of methylation changes in genes associated with organ development, morphology and mineralization of bone, whereas changes in boys were found in cell death-related genes. Several individual CpG sites that were positively associated with cadmium were inversely correlated with birth weight, although none statistically significant after correction for multiple comparisons. The associations were, however, fairly robust in multivariable-adjusted linear regression models. We identified CpG sites that were significantly associated with cadmium exposure in both newborns and 4.5-y-old children. In conclusion, cadmium exposure in early life appears to alter DNA methylation differently in girls and boys. This is consistent with previous findings of sex-specific cadmium toxicity. Cadmium-related changes in methylation were also related to lower birth weight. 相似文献
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Mads Lausen Gunna Christiansen Nichlas Karred Robert Winther Thomas Bouet Guldbæk Poulsen Yaseelan Palarasah Svend Birkelund 《Microbes and infection / Institut Pasteur》2018,20(6):328-336
Chlamydia trachomatis is an obligate intracellular bacterium that causes severe infections, which can lead to infertility and ectopic pregnancy. Although both innate and adaptive immune responses are elicited during chlamydial infection the bacterium succeeds to evade host defense mechanisms establishing chronic infections. Thus, studying the host–pathogen interaction during chlamydial infection is of importance to understand how C. trachomatis can cause chronic infections. Both the complement system and monocytes play essential roles in anti-bacterial defense, and, therefore, we investigated the interaction between the complement system and the human pathogens C. trachomatis D and L2.Complement competent serum facilitated rapid uptake of both chlamydial serovars into monocytes. Using immunoelectron microscopy, we showed that products of complement C3 were loosely deposited on the bacterial surface in complement competent serum and further characterization demonstrated that the deposited C3 product was the opsonin iC3b. Using C3-depleted serum we confirmed that complement C3 facilitates rapid uptake of chlamydiae into monocytes in complement competent serum. Complement facilitated uptake did not influence intracellular survival of C. trachomatis or C. trachomatis-induced cytokine secretion. Hence, C. trachomatis D and L2 activate the complement system leading to chlamydial opsonization by iC3b and subsequent phagocytosis, activation and bacterial elimination by human monocytes. 相似文献
116.
Anders Broberg Louise Malmgren Mats Jansson 《Journal of Aquatic Ecosystem Stress and Recovery (Formerly Journal of Aquatic Ecosystem Health)》1995,4(4):285-294
In many Swedish lakes, the fallout of 137Cs from the Chernobyl accident in April 1986 has largely accumulated in the sediments. The availability and transfer of deposited 137Cs to biota is influenced by factors such as resuspension. The frequency of resuspension and the 137Cs-content of different fish species was studied in three shallow lakes in Uppland, central Sweden, and in one deeper lake in northern Sweden. Resuspension was measured by the use of sediment traps. Sedimentation rates measured from the traps in the shallower lakes were 5–10 times higher than normal for this type of lake, indicating that resuspension was an important factor. The decrease of the 137Cs-content in muscle tissue of pike, perch and roach was slow in each of the shallow lakes. 137Cs decreased by about 30% over a period of 2 years in the shallowest lake (maximum depth 4 m), whereas 137Cs decreased by 50% in the deeper lakes (maximum depth 10 m). The slower rates of decline of 137Cs in biota from the shallow lakes, are probably a function of sediment dynamics (mainly influenced by lake morphometry, wind direction and strength). They may be influenced, also, by bioavailability of resuspended sediment material. In the deepest northern lake, much of the 137Cs-containing material collected in the sediment traps originated from the catchment area. Resuspension was minimal, and the high activity of 137Cs in the sediment had no effect on content or decline of 137Cs in lake fish. 相似文献
117.
Glucose formation in human skeletal muscle. Influence of glycogen content. 总被引:1,自引:0,他引:1
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Eight men exercised at 66% of their maximal isometric force to fatigue after prior decrease in the glycogen store in one leg (low-glycogen, LG). The exercise was repeated with the contralateral leg (control) at the same relative intensity and for the same duration. Muscle (quadriceps femoris) glycogen content decreased in the LG leg from 199 +/- 17 (mean +/- S.E.M.) to 163 +/- 16 mmol of glucosyl units/kg dry wt. (P less than 0.05), and in the control leg from 311 +/- 23 to 270 +/- 18 mmol/kg (P less than 0.05). The decrease in glycogen corresponded to a similar accumulation of glycolytic intermediates. Muscle glucose increased in the LG leg during the contraction, from 1.8 +/- 0.1 to 4.3 +/- 0.6 mmol/kg dry wt. (P less than 0.01), whereas no significant increase occurred in the control leg (P greater than 0.05). It is concluded that during exercise glucose is formed from glycogen through the debranching enzyme when muscle glycogen is decreased to values below about 200 mmol/kg dry wt. 相似文献
118.
K. Broberg Janusz Limon E. Pålsson Anders Lindstrand Sören Toksvig-Larsen Nils Mandahl Fredrik Mertens 《Human genetics》1997,101(3):295-298
We have previously reported recurrent clonal chromosomal aberrations in synovia, osteophytes and articular cartilage from
patients with osteoarthritis (OA). In particular, gain of chromosomes 5 and 7 was found to be strongly associated with OA.
In order to exclude the possibility of in vitro artefacts, we studied three to four parallel, independent cultures from ten
samples of synovia and three samples of osteophytes from ten women with primary OA. In all, 40 cultures were cytogenetically
analysed, 39 of which had clonal chromosomal aberrations. The most common aberrations were +7 and +5 which were found in 38
and 12 cultures, respectively. There were striking karyotype similarities among the parallel cultures from each case. Out
of a total of 83 clones, only 11 were unique for one culture, 7 from synovia and 4 from osteophytes. The genetic homogeneity
among different cultures from the same patients excludes the possibility of in vitro artefacts and indicates a widespread
distribution of the cytogenetically aberrant clones in vivo.
Received: 16 July 1997 / Accepted: 25 August 1997 相似文献
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Pawel Michalak Lin Kang Mads F. Schou Harold R. Garner Volker Loeschcke 《Molecular ecology》2019,28(3):600-614
Abiotic environmental factors play a fundamental role in determining the distribution, abundance and adaptive diversification of species. Empowered by new technologies enabling rapid and increasingly accurate examination of genomic variation in populations, researchers may gain new insights into the genomic background of adaptive radiation and stress resistance. We investigated genomic variation across generations of large‐scale experimental selection regimes originating from a single founder population of Drosophila melanogaster, diverging in response to ecologically relevant environmental stressors: heat shock, heat knock down, cold shock, desiccation and starvation. When compared to the founder population, and to parallel unselected controls, there were more than 100,000 single nucleotide polymorphisms (SNPs) displaying consistent allelic changes in response to selective pressures across generations. These SNPs were found in both coding and noncoding sequences, with the highest density in promoter regions, and involved a broad range of functionalities, including molecular chaperoning by heat‐shock proteins. The SNP patterns were highly stressor‐specific despite considerable variation among line replicates within each selection regime, as reflected by a principal component analysis, and co‐occurred with selective sweep regions. Only ~15% of SNPs with putatively adaptive changes were shared by at least two selective regimes, while less than 1% of SNPs diverged in opposite directions. Divergent stressors driving evolution in the experimental system of adaptive radiation left distinct genomic signatures, most pronounced in starvation and heat‐shock selection regimes. 相似文献