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461.
Telocytes (TCs) were identified as a distinct cellular type of the interstitial tissue and defined as cells with extremely long telopodes (Tps). Our previous data demonstrated patterns of mouse TC‐specific gene profiles on chromosome 1. The present study focuses on the identification of characters and patterns of TC‐specific or TC‐dominated gene expression profiles in chromosome 2 and 3, the network of principle genes and potential functional association. We compared gene expression profiles of pulmonary TCs, mesenchymal stem cells, fibroblasts, alveolar type II cells, airway basal cells, proximal airway cells, CD8+T cells from bronchial lymph nodes (T‐BL), and CD8+ T cells from lungs (T‐LL). We identified that 26 or 80 genes of TCs in chromosome 2 and 13 or 59 genes of TCs up‐ or down‐regulated in chromosome 3, as compared with other cells respectively. Obvious overexpression of Myl9 in chromosome 2 of TCs different from other cells, indicates that biological functions of TCs are mainly associated with tissue/organ injury and ageing, while down‐expression of Pltp implies that TCs may be associated with inhibition or reduction of inflammation in the lung. Dominant overexpression of Sh3glb1, Tm4sf1 or Csf1 in chromosome 3 of TCs is mainly associated with tumour promotion in lung cancer, while most down‐expression of Pde5 may be involved in the development of pulmonary fibrosis and other acute and chronic interstitial lung disease.  相似文献   
462.
Telocytes have been reported to play an important role in long‐distance heterocellular communication in normal and diseased heart, both through direct contact (atypical junctions), as well as by releasing extracellular vesicles (EVs) which may act as paracrine mediators. Exosomes and ectosomes are the two main types of EVs, as classified by size and the mechanism of biogenesis. Using electron microscopy (EM) and electron tomography (ET) we have found that telocytes in culture release at least three types of EVs: exosomes (released from endosomes; 45 ± 8 nm), ectosomes (which bud directly from the plasma membrane; 128 ± 28 nm) and multivesicular cargos (MVC; 1 ± 0.4 μm), the latter containing tightly packaged endomembrane‐bound vesicles (145 ± 35 nm). Electron tomography revealed that endomembrane vesicles are released into the extracellular space as a cargo enclosed by plasma membranes (estimated area of up to 3 μm2). This new type of EV, also released by telocytes in tissue, likely represents an essential component in the paracrine secretion of telocytes and may consequently be directly involved in heart physiology and regeneration.  相似文献   
463.
The North of Romania is known for its wooden churches dating from the seventeenth and eighteenth centuries. Their deterioration constitutes a major problem due to their value for the cultural heritage. The microbial community from a seventeenth-century wooden church (Nicula, Romania) was investigated by characterization of uncultivated and cultivated bacteria using 16S rDNA sequence analysis. The study revealed not only the prevalence of the Bacillus thuringiensis strain IAM 12077 but also the presence of new microbial communities of Planomicrobium and Variovorax that were not previously reported in paintings or on wood. The identification of fungi showed the presence of seven common genera found on the walls and icon surfaces. Common bacteria from the human oral microbiota were not identified in the bacterial community.  相似文献   
464.

Aims

The study investigated the effects of the combined treatment Parecoxib (Pcox) and 5,10,15,20-tetra-sulphonato-phenyl-porphyrin(TSPP)-mediated photodynamic therapy on Walker 256 carcinosarcoma.

Main methods

Five groups of male Wistar rats were used: the control group, treated with TSPP, group 2, irradiated 24 h thereafter, group 3, treated with Pcox and irradiated 24 h thereafter, groups 4 and 5 treated with combined therapies, TSPP and Pcox before irradiation, and Pcox 24 h after TSPP and irradiation respectively. Tumour inflammation, growth and non-growth factors, apoptosis/necrosis rate and oxidative/nitrosative stress markers were investigated.

Key findings

Malondialdehyde levels and cyclooxygenase (COX)-2 expression increased significantly in the group treated with Pcox after TSPP-PDT when compared with TSPP + IR group (p < 0.05, p < 0.001 respectively), in correlation with a decrease in glutathione levels (p < 0.05). The quantification of apoptosis, based on the TUNEL-assay, and necrosis rate revealed an increase of apoptotic/necrotic index in the same group (p < 0.05). On the other hand, Pcox administered before irradiation showed a significant increase in both vascular endothelial growth factor (VEGF) and COX-2 levels (p < 0.05) and in nitric oxide production (p < 0.01), when compared with the control group.

Significance

The administration of Pcox after TSPP-mediated PDT showed promising antitumoural effects, leading to an increase in oxidative and nitrosative stress as well as apoptosis/necrosis rate in tumour tissue. These results show that combined regimens that involve selective COX-2 inhibitors administration after irradiation may improve the therapeutic effectiveness of PDT.  相似文献   
465.
Avoiding toxins in food is as important as obtaining nutrition. Conditioned food aversions have been studied in animals as diverse as nematodes and humans [1, 2], but the neural signaling mechanisms underlying this form of learning have been difficult to pinpoint. Honeybees quickly learn to associate floral cues with food [3], a trait that makes them an excellent model organism for studying the neural mechanisms of learning and memory. Here we show that honeybees not only detect toxins but can also learn to associate odors with both the taste of toxins and the postingestive consequences of consuming them. We found that two distinct monoaminergic pathways mediate learned food aversions in the honeybee. As for other insect species conditioned with salt or electric shock reinforcers [4-7], learned avoidances of odors paired with bad-tasting toxins are mediated by dopamine. Our experiments are the first to identify a second, postingestive pathway for learned olfactory aversions that involves serotonin. This second pathway may represent an ancient mechanism for food aversion learning conserved across animal lineages.  相似文献   
466.
One of the most important objects in bioinformatics is a gene product (protein or RNA). For many gene products, functional information is summarized in a set of Gene Ontology (GO) annotations. For these genes, it is reasonable to include similarity measures based on the terms found in the GO or other taxonomy. In this paper, we introduce several novel measures for computing the similarity of two gene products annotated with GO terms. The fuzzy measure similarity (FMS) has the advantage that it takes into consideration the context of both complete sets of annotation terms when computing the similarity between two gene products. When the two gene products are not annotated by common taxonomy terms, we propose a method that avoids a zero similarity result. To account for the variations in the annotation reliability, we propose a similarity measure based on the Choquet integral. These similarity measures provide extra tools for the biologist in search of functional information for gene products. The initial testing on a group of 194 sequences representing three proteins families shows a higher correlation of the FMS and Choquet similarities to the BLAST sequence similarities than the traditional similarity measures such as pairwise average or pairwise maximum.  相似文献   
467.
This paper presents two new experimental results: the protective effect of green light (GL) on ultraviolet (UV) denaturation of proteins, and the effect of GL on protein macromolecular structures. The protective effect of GL was revealed on two serum albumins, bovine (BSA) and human (HSA), and recorded by electrophoresis, absorption, and circular dichroism spectra. The effect of GL irradiation on protein structure was recorded by using fluorescence spectroscopy and electrophoresis. These new effects were modeled by quantum-chemistry computation using Gaussian 03W, leading to good fit between theoretical and experimental absorption and circular dichroism spectra. A mechanism for these phenomena is suggested, based on a double-photon absorption process. This nonlinear effect may lead to generation of long-lived Rydberg macromolecular systems, capable of long-range interactions. These newly suggested systems, with macroscopic quantum coherence behaviors, may block the UV denaturation processes.  相似文献   
468.
469.
Syrian hamster constitutive heterochromatin was analyzed for C-band distribution and for BrU late-replication pattern. Characteristic for this species is relatively large amounts of sex-chromosome and autosomal heterochromatin. The distribution of constitutive heterochromatin was determined. The long term of the X chromosome, the whole Y, the short arms of 8 autosomal pairs, the long arm of the smallest metacentric pair, and the centromeric regions of 12 pairs stained intensely dark on C-band preparations. In contrast to the heterochromatin in the centromeric regions, the autosomal short-arm heterochromatin has an increased susceptibility to the denaturation process, as indicated by prolonged exposure to NaOH or Ba(OH)2. Such further exposure to denaturing agents results in an intense dark stain only on the sex-chromosome heterochromatin and centromeric regions of the autosomes. The BrdU late-replication pattern demonstrated that the late-replicating regions correspond to C-bands. Centromeric regions replicate late in the S phase; however, no centromeric region is among the latest replicating segments of the complement. Centromeric and noncentromeric heterochromatin are two distinct categories of constitutive heterochromatin.  相似文献   
470.
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