Background: The hyaluronan receptor CD44 interacts with the PDGF β-receptor and the TGFβ type I receptor. Results: CD44, PDGF β-receptor and TGFβ type I receptor affect each other's signaling, stability and function. Conclusion: Cross-talk between PDGF β-receptor and TGFβ type I receptor occurs in human dermal fibroblasts. Significance: This study reveals novel modulatory mechanisms of PDGF and TGFβ signaling. Growth factors, such as platelet-derived growth factor BB (PDGF-BB) and transforming growth factor β (TGFβ), are key regulators of cellular functions, including proliferation, migration, and differentiation. Growth factor signaling is modulated by context-dependent cross-talk between different signaling pathways. We demonstrate in this study that PDGF-BB induces phosphorylation of Smad2, a downstream mediator of the canonical TGFβ pathway, in primary dermal fibroblasts. The PDGF-BB-mediated Smad2 phosphorylation was dependent on the kinase activities of both TGFβ type I receptor (TβRI) and PDGF β-receptor (PDGFRβ), and it was prevented by inhibitory antibodies against TGFβ. Inhibition of the activity of the TβRI kinase greatly reduced the PDGF-BB-dependent migration in dermal fibroblasts. Moreover, we demonstrate that the receptors for PDGF-BB and TGFβ interact physically in primary dermal fibroblasts and that stimulation with PDGF-BB induces internalization not only of PDGFRβ but also of TβRI. In addition, silencing of PDGFRβ by siRNA decreased the stability of TβRI and delayed TGFβ-induced signaling. We further show that the hyaluronan receptor CD44 interacts with both PDGFRβ and TβRI. Depletion of CD44 by siRNA increased signaling via PDGFRβ and TβRI by stabilizing the receptor proteins. Our data suggest that cross-talk between PDGFRβ and TβRI occurs in dermal fibroblasts and that CD44 negatively modulates signaling via these receptors.
E-mail: meldi@bih.net.ba Heart rate variability, a phenomenon of variations of the length of consecutive heat cycles reflects the autonomic modulation of the heart function. Parameters of monitoring the heart rate variability are suggested to be important in the assessment of autonomic neuropathy that may complicate several pathological conditions, with established clinical importance in predicting morbidity and mortality in patients with coronary syndrome and in patients with diabetes mellitus. The complexity of the critical illness of the subjects in the intensive care unit demands complex pharmacological and procedural therapeutic interventions and measures, which all have a significant impact on the parameters of heart rate variability. Such complex interactions limit the possibility to reach conclusions on a potential degree of the influences of the deteriorated organ function and the influence of the therapeutic interventions. Despite difficulties and limitations of interpretation of the variations and depression of the heart rate variability parameters, research in this field has been continuing. In this paper, different parameters of short-term heart rate variability monitored in 25 consecutive patients who were admitted to an adult intensive care medicine unit for different conditions of critical illness are presented.
An implantable wireless Doppler device used in microsurgical free flap surgeries can suffer from lost data points. To recover the lost samples, the authors considered the approaches based on a recently proposed compressive sensing. In this paper, they performed a comparative analysis of several different approaches by using synthetic and real signals obtained during blood flow monitoring in four pigs. They considered three different bases functions: Fourier bases, discrete prolate spheroidal sequences and modulated discrete prolate spheroidal sequences, respectively. To avoid the computational burden, they considered the approaches based on the l 1 minimisation for all the three bases. To understand the trade-off between the computational complexity and the accuracy, they also used a recovery process based on a matching pursuit and modulated discrete prolate spheroidal sequences bases. For both the synthetic and the real signals, the matching approach with modulated discrete prolate spheroidal sequences provided the most accurate results. Future studies should focus on the optimisation of the modulated discrete prolate spheroidal sequences in order to further decrease the computational complexity and increase the accuracy.
This paper concerns available steganographic techniques that can be used for sending hidden data through public network. Typically, in steganographic communication it is advised to use popular/often used method for sending hidden data and amount of that data need to be high as much as possible. We confirmed this by choosing a Domain Name System (DNS) as a vital protocol of each network and choosing Distributed denial of service (DDoS) attacks that are most popular network attacks currently represented in the world. Apart from characterizing existing steganographic methods we provide new insights by presenting two new techniques. The first one is network steganography solution which exploits free/unused protocols fields and is known for IP, UDP or TCP protocols, but has never been applied to DNS (Domain Name Server) which are the fundamental part of network communications. The second explains the usage of DNS Amplification DDoS Attack to send seamlessly data through public network. The calculation that was performed to estimate the total amount of data that can be covertly transferred by using these technique, regardless of steganalysis, is included in this paper.
Emotional states of humans and their impact on physiological and neurological characteristics are discussed in this paper. This problem is the goal of many teams who have dealt with this topic. Nowadays, it is necessary to increase the accuracy of methods for obtaining information about correlations between emotional state and physiological changes. To be able to record these changes, we focused on two majority emotional states. Studied subjects were psychologically stimulated to neutral - calm and then to the stress state. Electrocardiography, Electroencephalography and blood pressure represented neurological and physiological samples that were collected during patient’s stimulated conditions. Speech activity was recording during the patient was reading selected text. Feature extraction was calculated by speech processing operations. Classifier based on Gaussian Mixture Model was trained and tested using Mel-Frequency Cepstral Coefficients extracted from the patient's speech. All measurements were performed in a chamber with electromagnetic compatibility. The article discusses a method for determining the influence of stress emotional state on the human and his physiological and neurological changes.
Background: For the assessment of the left ventricular function and infarct size in acute myocardial infarction, brain natriuretic peptide (BNP) and cardiac troponin I (cTnI) are useful for the prediction of a prognosis. The aim of the present study was to correlate left ventricular function and infarct size to the level of cTnI and BNP in acute myocardial infarction. Patients and Methods: We studied 40 patients (pts), with the first ST-segment elevation myocardial infarction (STEMI). We measured the level of BNP and cTnI on a single occasion at 96 hours after the onset of symptoms, and then compared it with echocardiography estimated systolic and diastolic ventricular function and infarct size — which was determined with numbers of ECG leads and classification into small and large infarct size (small infarct size 3-4 leads, large infarct size 6-9 leads). Results: Distribution of data was estimated by using the Shapiro-Wilk test. The data do not have normal distribution, so they are representative as a median and range. We used non-parametric statistic tests (Mann-Whitney tests) to compare and improve differences among the groups. For statistical correlation, we used the Sperman rank correlation. Data were analyzed using statistical program Arcus Quick Stat. There was significant inverse correlation between the level of BNP and EF (r = -0.504, P = 0.0016) and between BNP i E/A (r = -0.290, P = 0.00705). There was a strong inverse correlation between BNP and LV-EF in STEMI, such as between BNP and E/A, against cTnI no significant correlation with LV-EF and E/A in STEMI was found. There is no significant statistical difference between BNP and cTnI in small and large infarct size. Conclusion: A single BNP value at 96 hours after the onset symptoms of myocardial infarction proved useful for the estimation of LV systolic and diastolic function. In a direct comparison BNP disclosed a better performance for the estimation of LV-EF and E/A against cTnI. cTnI is useful for diagnosing early myocardial damage in acute myocardial infarction, suggesting an implementation of dual marker strategy in acute myocardial infarction for diagnostic and prognostic work-up.
Nema pronađenih rezultata, molimo da izmjenite uslove pretrage i pokušate ponovo!
Ova stranica koristi kolačiće da bi vam pružila najbolje iskustvo
Saznaj više