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171.
Germ cell tumours predominantly of the testis ((T)GCTs) are remarkably chemotherapy sensitive. However, a small proportion of patients fail to be cured with cisplatin‐based combination chemotherapy. miR‐371a‐3p is a new liquid biopsy biomarker for (T)GCTs. The aim of this study was to evaluate clinical utility of plasma miR‐371a‐3p level in patients starting systemic chemotherapy. Patients were included before the first cycle (N = 180) and second cycle (N = 101) of systemic first line chemotherapy, treated between July 2010 and May 2017. Plasma miR‐371a‐3p levels were measured with the ampTSmiR test and compared to disease characteristics and outcome. Pretreatment plasma miR‐371a‐3p levels were increased in 51.7% of cases and associated with number of metastatic sites, presence of lung, retroperitoneal, and mediastinal lymph node metastases, S – stage, IGCCCG risk group, and response to therapy. Patients with a negative pretreatment plasma level had better progression‐free survival (PFS) and overall survival (OS) compared to patients being positive for miR‐371a‐3p (hazard ratio [HR] = 0.26, 95% confidence interval [CI] 0.09‐0.71, = 0.02 for PFS and HR = 0.21, 95% CI 0.07‐0.67, = 0.03 for OS, respectively). Patients negative for miR‐371a‐3p in both samples had a superior PFS (HR = 0.10, 95% CI 0.01‐21.49, P = 0.02) and OS (HR = 0.08, 95% CI 0.01‐27.81, P = 0.008) compared to patients with miR‐371a‐3p positive in both samples (multivariate analyses were non‐significant). In total 68% of the patients were S0. This study demonstrates clinical value of plasma miR‐371a‐3p level in chemotherapy naïve (T)GCT patients starting first line of chemotherapy to predict prognosis.  相似文献   
172.
Epidemiological studies indicate a high risk of stroke, heart failure and myocardial infarction in patients with multiple sclerosis, especially in its secondary progressive (SPMS) phase. Some ischaemic events are directly associated with abnormal platelet functions and their prothrombotic activity. Recent reports, including this study, confirm the increased activation of circulating platelets in SPMS, and also show increased platelet reactivity, among other responses, as well as strong aggregation. In this current study, we conducted a comparative analysis of the platelet proteome in SPMS patients and in healthy controls, to demonstrate the quantitative and qualitative differences likely to affect functional changes observed in SPMS. During densitometry evaluation of 2‐D fluorescence difference gel electrophoresis, we observed differences between the electrophoretic patterns of SPMS platelets and the control samples. To determine a detailed characterisation of the proteome changes in the SPMS patients’ blood platelets, in the next stage, we performed mass spectrometry of selected spots and indicated the increased presence of four proteins (fibrinogen, α‐2 macroglobulin, septin‐14 and tubulin β‐1 chain). The most important of these is the increased amount of prothrombotic protein, fibrinogen, which seems to confirm the accuracy of the imaging and potentially explains the increased risk of platelet‐origin thrombotic events. This study provides new knowledge of the potential existence of the molecular mechanisms responsible for the acceleration of the platelet pro‐coagulant function in SPMS. This can help to identify new targets for therapy, which can then be used not only in the second stage of the disease.  相似文献   
173.
Human Papillomavirus (HPV) remains one of the most commonly contracted sexually transmitted diseases around the world. There are a multitude of HPV types, some of which may never present any symptoms. Others, however, are considered high-risk types, which increase the chance of the person infected to develop cancer. In recent years, the utilization of nanotechnology has allowed researchers to employ and explore the use of nanoparticles in immunotherapies.The new nanoparticle frontier has opened many doors in this area of research as a form of prevention, diagnosis, and treatment in cancers resulting from HPV. This review will provide a brief background of HPV, its relationship to head and neck cancer (HNC) and present some insight into the field of immunotherapeutic nanoparticles.  相似文献   
174.
Extremophiles - Genotypic and morphological diversity of cyanobacteria in the Rupite hot spring (Bulgaria) was investigated by means of optical microscopy, cultivation, single-cell PCR, and 16S...  相似文献   
175.
19-Hydroxyeicosatetraenoic acid (19-HETE, 1), a metabolically and chemically labile cytochrome P450 eicosanoid, has diverse biological activities including antagonism of the vasoconstrictor 20-hydroxyeicosatetraenoic acid (20-HETE, 2). A SAR study was conducted to develop robust analogs of 1 with improved in vitro and in vivo efficacy. Analogs were screened in vitro for inhibition of 20-HETE-induced sensitization of rat renal preglomerular microvessels toward phenylephrine and demonstrated to normalize the blood pressure of male Cyp4a14(-/-) mice that display androgen-driven, 20-HETE-dependent hypertension.  相似文献   
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Calreticulin is an endoplasmic reticulum Ca2+-storage protein, which influences gene expression and cell adhesion. In this study, we show that calreticulin induces fibronectin gene expression and matrix deposition, leading to differences in cell spreading and focal adhesion formation in cells differentially expressing calreticulin. We further show that these effects of calreticulin occur via a c-Src-regulated pathway and that c-Src activity is inversely related to calreticulin abundance. Since c-Src is an important regulator of focal contact turnover, we investigated the effect of c-Src inhibition on cells differentially expressing calreticulin. Inhibition of c-Src rescued the poorly adhesive phenotype of the calreticulin-underexpressing cells in that they became well spread, commenced formation of numerous focal contacts, and deposited a rich fibronectin matrix. Importantly, we show that c-Src activity is dependent on releasable Ca2+ from the endoplasmic reticulum, thus implicating Ca2+-sensitive pathways that are affected by calreticulin in cell-substratum adhesion. We propose that calreticulin affects fibronectin synthesis and matrix assembly via the regulation of fibronectin gene expression. In parallel, calcium-dependent effects of calreticulin on c-Src activity influence the formation and/or stability of focal contacts, which are instrumental in matrix assembly and remodeling.  相似文献   
180.
MDC1 (NFBD1), a mediator of the cellular response to DNA damage, plays an important role in checkpoint activation and DNA repair. Here we identified a cross-talk between the DNA damage response and cell cycle regulation. We discovered that MDC1 binds the anaphase-promoting complex/cyclosome (APC/C), an E3 ubiquitin ligase that controls the cell cycle. The interaction is direct and is mediated by the tandem BRCA1 C-terminal domains of MDC1 and the C terminus of the Cdc27 (APC3) subunit of the APC/C. It requires the phosphorylation of Cdc27 and is enhanced after induction of DNA damage. We show that the tandem BRCA1 C-terminal domains of MDC1, known to directly bind the phosphorylated form of histone H2AX (gamma-H2AX), also bind the APC/C by the same mechanism, as phosphopeptides that correspond to the C termini of gamma-H2AX and Cdc27 competed with each other for the binding to MDC1. Our results reveal a link between the cellular response to DNA damage and cell cycle regulation, suggesting that MDC1, known to have a role in checkpoint regulation, executes part of this role by binding the APC/C.  相似文献   
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