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71.
Nedra Badri Maroua Mhamdi Ridha Ben Ali Horea Matei Walid-Habib Tekaya Adrian Florea Samira Maghraoui Leila Tekaya 《Biological trace element research》2018,183(2):280-287
Gold, a heavy yellow-colored metal, is usually found in nature as a metallic element or as salts. This noble metal historically had a reputation as an anti-inflammatory medicine for rheumatoid arthritis, a nervine, and a remedy for nervous disorders, as well as a potential anticancer agent. It has also been used as component in dental restorations and in implant materials. The present study was undertaken to point out histological and ultrastructural effects of gold, administered by intraperitoneal route, in pregnant female reproductive organs (ovary and uterus), in order to clarify its side effects on the reproductive function. Using the transmission electron microscopy (TEM), the ultrastructural investigations of both ultrathin ovarian and uterine sections of treated pregnant rats revealed the existence of numerous heterogeneous clusters with very electron-dense inclusions characterized by various aspects in the lysosomes of granulosa, theca interna cells, and theca externa cells. Degeneration of these tissues, like cell vacuolization, marked expansion of the endoplasmic reticulum, mitochondrial alterations, and necrotic foci, were also highlighted. Moreover, huge phagolysosomes and high numbers of eosinophils as signs of inflammation were also identified especially in endometrial and myometrial cells of gold-treated rats. The ultrastructural investigations of reproductive organ sections of control pregnant rats showed a normal ultrastructural aspect and no loaded lysosomes. These results speculated the toxicity of gold at the used dose. The observed signs of toxicity allowed concluding that the important role of lysosome in the sequestration of this element under an insoluble form in all categories of cells in the studied tissues does not seem to be efficient. 相似文献
72.
Samira Benyoucef Didier Hober Lu Shen Faïza Ajana Donat De Groote Laurence Bocket-Mouton Yann Grard Georges Lion Virginie Vilain Pierre Wattr 《Microbiology and immunology》1997,41(12):939-946
Diluted whole blood (WB) culturing may be the most appropriate milieu in which to study cytokine production in vitro. We tested TNFα and IL-6 production using small volumes of WB (25 μl) from HIV-1 positive patients with a one-step procedure that combines WB stimulation with LPS, PHA and cytokine measurement. We studied 49 patients without secondary infection or at distance of secondary infection staged according to the 1993 classification of the CDC and 12 healthy seronegative subjects. Heparinized blood from 5 control subjects had been collected sequentially during a period of 5 months. The individual variations of TNFα and IL-6 production were limited for all these individuals. In 1 out of 20 CDC group A patients, 6 out of 17 CDC group B patients and 3 out of 12 CDC group C patients, we obtained higher values of TNFα than the mean + 2 S.D. of the control group. In 3 out of 20 CDC group A patients, 1 out of 17 CDC group B patients without AIDS and 5 out of 12 CDC group C patients, the TNFα values were lower than the mean ?2 S.D. of the control group. Low IL-6 values were obtained in 1 out of 20 CDC group A patients and 1 out of 17 CDC group B patients and 3 out of 12 CDC group C patients. There was no correlation between TNFα production in vitro and plasma level of TNFα. We found no correlation between the levels of cytokines and monocyte count or between the levels of cytokines and CD4 T-cell count in peripheral blood. Our data point out a disarray in TNFα and IL-6 production by WB from HIV-1 infected patients. The relationship between the disarray of cytokine production and cytopathogenicity of HIV-1 isolates in the P4 cell line was investigated in this study. We found a correlation between the high level of TNFα produced by WB and the phenotype of HIV-1 isolates isolated from patients. The one-stage procedure used in this work is of potential value to investigate the activation status of cells for monitoring HIV-1 positive individuals and predicting HIV-1 phenotype. 相似文献
73.
Zhaleh Fakhri Ghader Mirzaghaderi Samira Ahmadian Annaliese S. Mason 《Plant cell reports》2016,35(5):1143-1154
Key message
The presence of homologous subgenomes inhibited unreduced gamete formation in wheat × Aegilops interspecific hybrids. Unreduced gamete rates were under the control of the wheat nuclear genome.Abstract
Production of unreduced gametes is common among interspecific hybrids, and may be affected by parental genotypes and genomic similarity. In the present study, five cultivars of Triticum aestivum and two tetraploid Aegilops species (i.e. Ae. triuncialis and Ae. cylindrica) were reciprocally crossed to produce 20 interspecific hybrid combinations. These hybrids comprised two different types: T. aestivum × Aegilops triuncialis; 2n = ABDUtCt (which lack a common subgenome) and T. aestivum × Ae. cylindrica; 2n = ABDDcCc (which share a common subgenome). The frequency of unreduced gametes in F1 hybrids was estimated in sporads from the frequency of dyads, and the frequency of viable pollen, germinated pollen and seed set were recorded. Different meiotic abnormalities recorded in the hybrids included precocious chromosome migration to the poles at metaphase I and II, laggards in anaphase I and II, micronuclei and chromosome stickiness, failure in cell wall formation, premature cytokinesis and microspore fusion. The mean frequency of restitution meiosis was 10.1 %, and the mean frequency of unreduced viable pollen was 4.84 % in T. aestivum × Ae. triuncialis hybrids. By contrast, in T. aestivum × Ae. cylindrica hybrids no meiotic restitution was observed, and a low rate of viable gametes (0.3 %) was recorded. This study present evidence that high levels of homologous pairing between the D and Dc subgenomes may interfere with meiotic restitution and the formation of unreduced gametes. Variation in unreduced gamete production was also observed between T. aestivum × Ae. triuncialis hybrid plants, suggesting genetic control of this trait.74.
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77.
Inactivation of photosynthesis during atmospheric and osmotic (highly concentrated NaCl or sucrose solutions) dehydration
was monitored by measurement of chlorophyll fluorescence induction (OIP-phase, Kautsky-curves) in three lichen species. The
induction curves were changed in a very similar way by all three treatments. All dehydration effects were rapidly reversible
after rehydration. At relatively mild water stress, the rise time to the transient peak Fp was prolonged, and the variable part of fluorescence was diminished. In addition, at severe water stress, a considerable
decline of the F0 value was observed. For NaCl treatment this effect started at water potentials <-8.5 MPa in P. aphthosa, <-12 MPa in H. physodes, and <-21 MPa in L. pulmonaria. Above these water potentials, our observations are in agreement with values from desiccation-tolerant algae, higher plants,
and lichens, where an inactivation on the photosystem 2 (PS2) donor side has been postulated. At very low water potentials,
the decrease in F0 probably monitors changes in the organization of the antenna apparatus of PS2.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
78.
79.
The FTD‐like syndrome causing TREM2 T66M mutation impairs microglia function,brain perfusion,and glucose metabolism
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Gernot Kleinberger Matthias Brendel Eva Mracsko Benedikt Wefers Linda Groeneweg Xianyuan Xiang Carola Focke Maximilian Deußing Marc Suárez‐Calvet Fargol Mazaheri Samira Parhizkar Nadine Pettkus Wolfgang Wurst Regina Feederle Peter Bartenstein Thomas Mueggler Thomas Arzberger Irene Knuesel Axel Rominger Christian Haass 《The EMBO journal》2017,36(13):1837-1853
Genetic variants in the triggering receptor expressed on myeloid cells 2 (TREM2) increase the risk for several neurodegenerative diseases including Alzheimer's disease and frontotemporal dementia (FTD). Homozygous TREM2 missense mutations, such as p.T66M, lead to the FTD‐like syndrome, but how they cause pathology is unknown. Using CRISPR/Cas9 genome editing, we generated a knock‐in mouse model for the disease‐associated Trem2 p.T66M mutation. Consistent with a loss‐of‐function mutation, we observe an intracellular accumulation of immature mutant Trem2 and reduced generation of soluble Trem2 similar to patients with the homozygous p.T66M mutation. Trem2 p.T66M knock‐in mice show delayed resolution of inflammation upon in vivo lipopolysaccharide stimulation and cultured macrophages display significantly reduced phagocytic activity. Immunohistochemistry together with in vivo TSPO small animal positron emission tomography (μPET) demonstrates an age‐dependent reduction in microglial activity. Surprisingly, perfusion magnetic resonance imaging and FDG‐μPET imaging reveal a significant reduction in cerebral blood flow and brain glucose metabolism. Thus, we demonstrate that a TREM2 loss‐of‐function mutation causes brain‐wide metabolic alterations pointing toward a possible function of microglia in regulating brain glucose metabolism. 相似文献
80.
Synthesis and in vitro Bioactivity Evaluation of New Galactose and Fructose Ester Derivatives of 5‐Aminosalicylic Acid
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Samira Yousefi Saadi Bayat Mohd Basyaruddin Abdul Rahman Zalikha Ibrahim Emilia Abdulmalek 《化学与生物多样性》2017,14(4)
Inflammatory bowel disease (IBD) is the main risk factor for developing colorectal cancer which is common in patients of all ages. 5‐Aminosalicylic acid (5‐ASA), structurally related to the salicylates, is highly active in the treatment of IBD with minor side effects. In this study, the synthesis of galactose and fructose esters of 5‐ASA was planned to evaluate the role of glycoconjugation on the bioactivity of the parent drug. The antibacterial activity of the new compounds were evaluated against two Gram‐negative and two Gram‐positive species of bacteria, with a notable effect observed against Staphylococcus aureus and Escherichia coli in comparisons with the 5‐ASA. Cytotoxicity testing over HT‐29 and 3T3 cell lines indicated that the toxicity of the new products against normal cells was significantly reduced compared with the original drug, whereas their activity against cancerous cells was slightly decreased. The anti‐inflammatory activity test in RAW264.7 macrophage cells indicated that the inhibition of nitric oxide by both of the monosaccharide conjugated derivatives was slightly improved in comparison with the non‐conjugated drug. 相似文献