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71.
72.
Although the biological significance of proteoglycans (PGs) has previously been highlighted in multiple myeloma (MM), little is known about serglycin, which is a hematopoietic cell granule PG. In this study, we describe the expression and highly constitutive secretion of serglycin in several MM cell lines. Serglycin messenger RNA was detected in six MM cell lines. PGs were purified from conditioned medium of four MM cell lines, and serglycin substituted with 4-sulfated chondroitin sulfate was identified as the predominant PG. Flow cytometry and confocal microscopy showed that serglycin was also present intracellularly and on the cell surface, and attachment to the cell surface was at least in part dependent on intact glycosaminoglycan side chains. Immunohistochemical staining of bone marrow biopsies showed the presence of serglycin both in benign and malignant plasma cells. Immunoblotting in bone marrow aspirates from a limited number of patients with newly diagnosed MM revealed highly increased levels of serglycin in 30% of the cases. Serglycin isolated from myeloma plasma cells was found to influence the bone mineralization process through inhibition of the crystal growth rate of hydroxyapatite. This rate reduction was attributed to adsorption and further blocking of the active growth sites on the crystal surface. The apparent order of the crystallization reaction was found to be n=2, suggesting a surface diffusion-controlled spiral growth mechanism. Our findings suggest that serglycin release is a constitutive process, which may be of fundamental biological importance in the study of MM.  相似文献   
73.
Purpose: To describe the baseline, 1?hr and delta high sensitivity cardiac troponin (hs-cTnT) values in patients with suspected acute myocardial infarction (AMI) but without a final acute coronary syndrome (ACS) diagnosis.

Materials and methods: hs-cTnT assay for RAPID rule out of acute myocardial infarction (TRAPID-AMI) was a prospective diagnostic trial that enrolled emergency department (ED) patients with suspected AMI. Final patient diagnoses were adjudicated by a clinical events committee and subjects placed in different clinical groups: AMI, unstable angina, non-ACS cardiac, non-cardiac and unknown origin. The baseline, 1?hr and delta hs-cTnT values were analysed in the 902 non-ACS patients.

Results: Amongst the 1282 studied the patient groups were 213 (17%) AMI, 167 (13%) unstable angina, 113 (9%) non-ACS cardiac, 288 (22%) non-cardiac and 501 (39%) unknown origin. The hs-cTnT values in the non-cardiac and unknown origin groups were combined. The median hs-cTnT values (ng/L) were higher (p?<?0.001) in the non-ACS cardiac compared to the non-cardiac/unknown origin group at baseline (11.8,?<5) and 1?hr (12.3,?<5). Their negative predictive values were 0.955 (baseline) and 0.954 (1?hr) for predicting non-ACS cardiac versus non-cardiac/unknown origin diagnoses.

Conclusions: Hs-cTnT may help predict whether non-ACS ED patients have a final non-ACS cardiac or non-cardiac/unknown origin diagnoses.  相似文献   

74.
A time series of survey abundance indices for commercially important demersal fish and cephalopod species, inhabiting the narrow continental shelf of the southern Aegean Sea, is analyzed in relation to the topography of the area in order to evaluate the impact of different spatial fishery bans on the bottom-trawl fishery. With reference to the current situation, results suggested that implementation of the 1967/2006 EC Regulation, which bans bottom-trawl activities within 1.5 NM off the coast, will significantly increase (20–80%, depending on the species) the proportion of the populations that are inaccessible to the bottom-trawl fishery. It might also result in shifting of fishing activities toward deeper waters, adding fishing pressure onto slope resources inhabiting the slope. As depth determines, to a large extent, the distribution pattern of the species, it constitutes a variable of crucial importance for the spatial management of marine fisheries and should be taken into account when adopting relevant management regimes.  相似文献   
75.
76.
During macroautophagy, conjugation of ATG12 to ATG5 is essential for LC3 lipidation and autophagosome formation. Additionally, ATG12 has ATG5-independent functions in diverse processes including mitochondrial fusion and mitochondrial-dependent apoptosis. In this study, we investigated the regulation of free ATG12. In stark contrast to the stable ATG12–ATG5 conjugate, we find that free ATG12 is highly unstable and rapidly degraded in a proteasome-dependent manner. Surprisingly, ATG12, itself a ubiquitin-like protein, is directly ubiquitinated and this promotes its proteasomal degradation. As a functional consequence of its turnover, accumulation of free ATG12 contributes to proteasome inhibitor-mediated apoptosis, a finding that may be clinically important given the use of proteasome inhibitors as anticancer agents. Collectively, our results reveal a novel interconnection between autophagy, proteasome activity, and cell death mediated by the ubiquitin-like properties of ATG12.  相似文献   
77.

Background

Analysis of data from multiple sources has the potential to enhance knowledge discovery by capturing underlying structures, which are, otherwise, difficult to extract. Fusing data from multiple sources has already proved useful in many applications in social network analysis, signal processing and bioinformatics. However, data fusion is challenging since data from multiple sources are often (i) heterogeneous (i.e., in the form of higher-order tensors and matrices), (ii) incomplete, and (iii) have both shared and unshared components. In order to address these challenges, in this paper, we introduce a novel unsupervised data fusion model based on joint factorization of matrices and higher-order tensors.

Results

While the traditional formulation of coupled matrix and tensor factorizations modeling only shared factors fails to capture the underlying structures in the presence of both shared and unshared factors, the proposed data fusion model has the potential to automatically reveal shared and unshared components through modeling constraints. Using numerical experiments, we demonstrate the effectiveness of the proposed approach in terms of identifying shared and unshared components. Furthermore, we measure a set of mixtures with known chemical composition using both LC-MS (Liquid Chromatography - Mass Spectrometry) and NMR (Nuclear Magnetic Resonance) and demonstrate that the structure-revealing data fusion model can (i) successfully capture the chemicals in the mixtures and extract the relative concentrations of the chemicals accurately, (ii) provide promising results in terms of identifying shared and unshared chemicals, and (iii) reveal the relevant patterns in LC-MS by coupling with the diffusion NMR data.

Conclusions

We have proposed a structure-revealing data fusion model that can jointly analyze heterogeneous, incomplete data sets with shared and unshared components and demonstrated its promising performance as well as potential limitations on both simulated and real data.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2105-15-239) contains supplementary material, which is available to authorized users.  相似文献   
78.
Perception of our environment is a multisensory experience; information from different sensory systems like the auditory, visual and tactile is constantly integrated. Complex tasks that require high temporal and spatial precision of multisensory integration put strong demands on the underlying networks but it is largely unknown how task experience shapes multisensory processing. Long-term musical training is an excellent model for brain plasticity because it shapes the human brain at functional and structural levels, affecting a network of brain areas. In the present study we used magnetoencephalography (MEG) to investigate how audio-tactile perception is integrated in the human brain and if musicians show enhancement of the corresponding activation compared to non-musicians. Using a paradigm that allowed the investigation of combined and separate auditory and tactile processing, we found a multisensory incongruency response, generated in frontal, cingulate and cerebellar regions, an auditory mismatch response generated mainly in the auditory cortex and a tactile mismatch response generated in frontal and cerebellar regions. The influence of musical training was seen in the audio-tactile as well as in the auditory condition, indicating enhanced higher-order processing in musicians, while the sources of the tactile MMN were not influenced by long-term musical training. Consistent with the predictive coding model, more basic, bottom-up sensory processing was relatively stable and less affected by expertise, whereas areas for top-down models of multisensory expectancies were modulated by training.  相似文献   
79.
Fossil testudinids are known in Europe since the Eocene, with several taxa of medium size (from more than 0.3 m to less than 0.7 m) recognized in the Palaeogene record, most of them being poorly known. The size of several European Neogene taxa was larger (between 1 and 2 m). These large testudinids were relatively abundant and diverse, ranging from the early Miocene to the Pleistocene. However, there is a nomenclatural gap at the generic level for the Neogene forms, as their generally used assignment to the more primitive Eocene Cheirogaster cannot be sustained. This is because relatively little material has been assigned to the described species, and also because of the absence of a detailed study comparing all of the European taxa. Here, the European Cenozoic taxa are incorporated for the first time in a data matrix, so that a hypothesis on their phylogenetic relationships is justified. This study identified the large testudinids from the Neogene of Europe as belonging to a monophyletic clade, assigned to the new genus T itanochelon . The hitherto poorly understood ‘Testudobolivari, proposed nearly a century ago but lacking diagnosis, is analysed in detail. It is recognized as the best‐represented large testudinid from the European record, and is identified as the type species of T itanochelon gen. nov. Its comparison with the other Neogene species allowed a detailed study of the new genus and an analysis of its phylogenetic relationships with the other European taxa. © 2014 The Linnean Society of London  相似文献   
80.
The speed of development, versatility and efficacy of mRNA-based vaccines have been amply demonstrated in the case of SARS-CoV-2. DNA vaccines represent an important alternative since they induce both humoral and cellular immune responses in animal models and in human trials. We tested the immunogenicity and protective efficacy of DNA-based vaccine regimens expressing different prefusion-stabilized Wuhan-Hu-1 SARS-CoV-2 Spike antigens upon intramuscular injection followed by electroporation in rhesus macaques. Different Spike DNA vaccine regimens induced antibodies that potently neutralized SARS-CoV-2 in vitro and elicited robust T cell responses. The antibodies recognized and potently neutralized a panel of different Spike variants including Alpha, Delta, Epsilon, Eta and A.23.1, but to a lesser extent Beta and Gamma. The DNA-only vaccine regimens were compared to a regimen that included co-immunization of Spike DNA and protein in the same anatomical site, the latter of which showed significant higher antibody responses. All vaccine regimens led to control of SARS-CoV-2 intranasal/intratracheal challenge and absence of virus dissemination to the lower respiratory tract. Vaccine-induced binding and neutralizing antibody titers and antibody-dependent cellular phagocytosis inversely correlated with transient virus levels in the nasal mucosa. Importantly, the Spike DNA+Protein co-immunization regimen induced the highest binding and neutralizing antibodies and showed the strongest control against SARS-CoV-2 challenge in rhesus macaques.  相似文献   
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