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21.
Frans C. S. Ramaekers Taco R. Boomkens Hans Bloemendal 《Experimental cell research》1981,135(2):454-461
Bovine lenses from animals of different ages were separated into two epithelial sections, a cortical region and the lens nucleus. Both the 10000 g supernatant fraction and pellet of these sections were analysed by electrophoresis in SDS-containing polyacrylamide gels. When comparing total protein patterns of the cytoskeletal preparations from the different parts of lenses of different ages a decrease in the amount of vimentin, the protein subunit of lens intermediate-sized filaments (IF), was observed upon lens cell differentiation and aging. Amounts of monomeric (G) and filamentous (F) actin in the different stages of lens cell differentiation were quantitated using the DNase I inhibition technique. A significant increase in the relative amount of F-actin was observed upon fibre cell formation. A slight, but significant increase in the total amount of actin relative to the total amount of cellular protein was observed when passing from the central part of the lens epithelium to the epithelial cells in the elongation zone. In the fibre cells the amount of total actin decreased from cortex to nucleus. A possible function of microfilament-assembly in the process of lens cell differentiation is suggested. 相似文献
22.
Daniela C. Granato Leandro X. Neves Luciana D. Trino Carolina M. Carnielli Ariane F.B. Lopes Sami Yokoo Bianca A. Pauletti Romênia R. Domingues Jamile O. Sá Gabriella Persinoti Douglas A.A. Paixão César Rivera Fabio M. de Sá Patroni Geizecler Tommazetto Alan R. Santos-Silva Márcio A. Lopes Gilberto de Castro Thaís B. Brandão Adriana F. Paes Leme 《Biochimica et Biophysica Acta - Proteins and Proteomics》2021,1869(8):140659
Saliva is a biofluid that maintains the health of oral tissues and the homeostasis of oral microbiota. Studies have demonstrated that Oral squamous cell carcinoma (OSCC) patients have different salivary microbiota than healthy individuals. However, the relationship between these microbial differences and clinicopathological outcomes is still far from conclusive. Herein, we investigate the capability of using metagenomic and metaproteomic saliva profiles to distinguish between Control (C), OSCC without active lesion (L0), and OSCC with active lesion (L1) patients. The results show that there are significantly distinct taxonomies and functional changes in L1 patients compared to C and L0 patients, suggesting compositional modulation of the oral microbiome, as the relative abundances of Centipeda, Veillonella, and Gemella suggested by metagenomics are correlated with tumor size, clinical stage, and active lesion. Metagenomics results also demonstrated that poor overall patient survival is associated with a higher relative abundance of Stenophotromonas, Staphylococcus, Centipeda, Selenomonas, Alloscordovia, and Acitenobacter. Finally, compositional and functional differences in the saliva content by metaproteomics analysis can distinguish healthy individuals from OSCC patients. In summary, our study suggests that oral microbiota and their protein abundance have potential diagnosis and prognosis value for oral cancer patients. Further studies are necessary to understand the role of uniquely detected metaproteins in the microbiota of healthy and OSCC patients as well as the crosstalk between saliva host proteins and the oral microbiome present in OSCC. 相似文献
23.
Evelyn Walenta Ariane R. Pessentheiner Helmut J. Pelzmann Alexander Deutsch Madeleine Goeritzer Dagmar Kratky Hubert Hackl Da Young Oh Andreas Prokesch Juliane G. Bogner-Strauss 《PloS one》2013,8(11)
Our knowledge about adipocyte metabolism and development is steadily growing, yet many players are still undefined. Here, we show that α/β-hydrolase domain containing protein 15 (Abhd15) is a direct and functional target gene of peroxisome proliferator-activated receptor gamma (PPARγ), the master regulator of adipogenesis. In line, Abhd15 is mainly expressed in brown and white adipose tissue and strongly upregulated during adipogenesis in various murine and human cell lines. Stable knockdown of Abhd15 in 3T3-L1 cells evokes a striking differentiation defect, as evidenced by low lipid accumulation and decreased expression of adipocyte marker genes. In preconfluent cells, knockdown of Abhd15 leads to impaired proliferation, which is caused by apoptosis, as we see an increased SubG1 peak, caspase 3/7 activity, and BAX protein expression as well as a reduction in anti-apoptotic BCL-2 protein. Furthermore, apoptosis-inducing amounts of palmitic acid evoke a massive increase of Abhd15 expression, proposing an apoptosis-protecting role for ABHD15. On the other hand, in mature adipocytes physiological (i.e. non-apoptotic) concentrations of palmitic acid down-regulate Abhd15 expression. Accordingly, we found that the expression of Abhd15 in adipose tissue is reduced in physiological situations with high free fatty acid levels, like high-fat diet, fasting, and aging as well as in genetically obese mice. Collectively, our results position ABHD15 as an essential component in the development of adipocytes as well as in apoptosis, thereby connecting two substantial factors in the regulation of adipocyte number and size. Together with its intricate regulation by free fatty acids, ABHD15 might be an intriguing new target in obesity and diabetes research. 相似文献
24.
Expectation contributes to placebo and nocebo responses in Parkinson''s disease (PD). While there is evidence for expectation-induced modulations of bradykinesia, little is known about the impact of expectation on resting tremor. Subthalamic nucleus (STN) deep brain stimulation (DBS) improves cardinal PD motor symptoms including tremor whereas impairment of verbal fluency (VF) has been observed as a potential side-effect. Here we investigated how expectation modulates the effect of STN-DBS on resting tremor and its interaction with VF. In a within-subject-design, expectation of 24 tremor-dominant PD patients regarding the impact of STN-DBS on motor symptoms was manipulated by verbal suggestions (positive [placebo], negative [nocebo], neutral [control]). Patients participated with (MedON) and without (MedOFF) antiparkinsonian medication. Resting tremor was recorded by accelerometry and bradykinesia of finger tapping and diadochokinesia were assessed by a 3D ultrasound motion detection system. VF was quantified by lexical and semantic tests. In a subgroup of patients, the effect of STN-DBS on tremor was modulated by expectation, i.e. tremor decreased (placebo response) or increased (nocebo response) by at least 10% as compared to the control condition while no significant effect was observed for the overall group. Interestingly, nocebo responders in MedON were additionally characterized by significant impairment in semantic verbal fluency. In contrast, bradykinesia was not affected by expectation. These results indicate that the therapeutic effect of STN-DBS on tremor can be modulated by expectation in a subgroup of patients and suggests that tremor is also among the parkinsonian symptoms responsive to placebo and nocebo interventions. While positive expectations enhanced the effect of STN-DBS by further decreasing the magnitude of tremor, negative expectations counteracted the therapeutic effect and at the same time exacerbated a side-effect often associated with STN-DBS. The present findings underscore the potency of patients'' expectation and its relevance for therapeutic outcomes. 相似文献
25.
Vincent Fraisier Amal Kasri Stéphanie Miserey-Lenkei Jean-Baptiste Sibarita Deepak Nair Adeline Mayeux Sabine Bardin Yusuke Toyoda Ina Poser Andrei Poznyakovskiy Bruno Goud Anthony A. Hyman Ariane Dimitrov 《PloS one》2013,8(12)
The Golgi apparatus is an intracellular compartment necessary for post-translational modification, sorting and transport of proteins. It plays a key role in mitotic entry through the Golgi mitotic checkpoint. In order to identify new proteins involved in the Golgi mitotic checkpoint, we combine the results of a knockdown screen for mitotic phenotypes and a localization screen. Using this approach, we identify a new Golgi protein C11ORF24 (NP_071733.1). We show that C11ORF24 has a signal peptide at the N-terminus and a transmembrane domain in the C-terminal region. C11ORF24 is localized on the Golgi apparatus and on the trans-Golgi network. A large part of the protein is present in the lumen of the Golgi apparatus whereas only a short tail extends into the cytosol. This cytosolic tail is well conserved in evolution. By FRAP experiments we show that the dynamics of C11ORF24 in the Golgi membrane are coherent with the presence of a transmembrane domain in the protein. C11ORF24 is not only present on the Golgi apparatus but also cycles to the plasma membrane via endosomes in a pH sensitive manner. Moreover, via video-microscopy studies we show that C11ORF24 is found on transport intermediates and is colocalized with the small GTPase RAB6, a GTPase involved in anterograde transport from the Golgi to the plasma membrane. Knocking down C11ORF24 does not lead to a mitotic phenotype or an intracellular transport defect in our hands. All together, these data suggest that C11ORF24 is present on the Golgi apparatus, transported to the plasma membrane and cycles back through the endosomes by way of RAB6 positive carriers. 相似文献
26.
Context
Health care technological evolution through new drugs, implants and other interventions is a key driver of healthcare spending. Policy makers are currently challenged to strengthen the evidence for and cost-effectiveness of reimbursement decisions, while not reducing the capacity for real innovations. This article examines six cases of reimbursement decision making at the national health insurance authority in Belgium, with outcomes that were contested from an evidence-based perspective in scientific or public media.Methods
In depth interviews with key stakeholders based on the adapted framework of Davies allowed us to identify the relative impact of clinical and health economic evidence; experience, expertise & judgment; financial impact & resources; values, ideology & political beliefs; habit & tradition; lobbyists & pressure groups; pragmatics & contingencies; media attention; and adoption from other payers & countries.Findings
Evidence was not the sole criterion on which reimbursement decisions were based. Across six equivocal cases numerous other criteria were perceived to influence reimbursement policy. These included other considerations that stakeholders deemed crucial in this area, such as taking into account the cost to the patient, and managing crisis scenarios. However, negative impacts were also reported, in the form of bypassing regular procedures unnecessarily, dominance of an opinion leader, using information selectively, and influential conflicts of interest.Conclusions
‘Evidence’ and ‘negotiation’ are both essential inputs of reimbursement policy. Yet, purposely selected equivocal cases in Belgium provide a rich source to learn from and to improve the interaction between both. We formulated policy recommendations to reconcile the impact of all factors identified. A more systematic approach to reimburse new care may be one of many instruments to resolve the budgetary crisis in health care in other countries as well, by separating what is truly innovative and value for money from additional ‘waste’. 相似文献27.
Erik Ziegler Ariane Foret Laura Mascetti Vincenzo Muto Anahita Le Bourdiec-Shaffii Johan Stender Evelyne Balteau Vinciane Dideberg Vincent Bours Pierre Maquet Christophe Phillips 《PloS one》2013,8(7)
Brain-derived neurotrophic factor (BDNF) modulates the pruning of synaptically silent axonal arbors. The Met allele of the BDNF gene is associated with a reduction in the neurotrophin''s activity-dependent release. We used diffusion-weighted imaging to construct structural brain networks for 36 healthy subjects with known BDNF genotypes. Through permutation testing we discovered clear differences in connection strength between subjects carrying the Met allele and those homozygotic for the Val allele. We trained a Gaussian process classifier capable of identifying the subjects'' allelic group with 86% accuracy and high predictive value. In Met carriers structural connectivity was greatly increased throughout the forebrain, particularly in connections corresponding to the anterior and superior corona radiata as well as corticothalamic and corticospinal projections from the sensorimotor, premotor, and prefrontal portions of the internal capsule. Interhemispheric connectivity was also increased via the corpus callosum and anterior commissure, and extremely high connectivity values were found between inferior medial frontal polar regions via the anterior forceps. We propose that the decreased availability of BDNF leads to deficits in axonal maintenance in carriers of the Met allele, and that this produces mesoscale changes in white matter architecture. 相似文献
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Reza Jafarzadeh-Esfehani Seyed Mostafa Parizadeh Amirsaeed Sabeti Aghabozorgi Negar Yavari Ariane Sadr-Nabavi Seyed Alireza Parizadeh Maryam Ghandehari Afsane Javanbakht Afsaneh Rezaei-Kalat Seyed Mahdi Hassanian Mohammad Vojdanparast Gordon A. Ferns Majid Khazaei Amir Avan 《Journal of cellular physiology》2020,235(10):6393-6403
Venous and arterial thrombosis are conditions that have a considerable burden if left untreated. The hypoxia-induced by the occluded vessel can disrupt the circulation of any organ, the cornerstone of treating thrombosis is rapid diagnosis and appropriate treatment. Diagnosis of thrombosis may be made by using laboratory tests or imaging techniques in individuals who have clinical manifestations of a thrombotic event. The use of serum micro ribonucleic acids (RNAs) has recently been applied to the diagnosis of thrombosis. These small RNA molecules are emerging as new diagnostic markers but have had very limited applications in vascular disease. Most of the articles provided various microRNAs with different levels of accuracy. However, there remains a lack of an appropriate panel of the most specific microRNA in the literature. The purpose of the present review was to summarize the existing data on the use of microRNAs as a diagnostic biomarker for venous thrombosis. 相似文献