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.
The goal of this study was to examine the effectiveness of 6 STR markers application (D21S1435, D21S11, D21S1270, D21S1411, D21S226 and IFNAR) in molecular genetic diagnostics of Down syndrome (DS) and to compare it with cytogenetic method. Testing was performed on 73 children, with the previously cytogenetically confirmed Down syndrome. DNA isolated from the buccal swab was used. Previously mentioned loci located on chromosome 21 were simultaneously amplified using quantitative fluorescence PCR (QF PCR). Using this method, 60 previously cytogenetically diagnosed DS with standard type of trisomy 21 were confirmed. Furthermore, six of eight children with mosaic type of DS were detected. Two false negative results for mosaic type of DS were obtained. Finally, five children with the translocation type of Down syndrome were also confirmed with this molecular test. In conclusion, molecular genetic analysis of STR loci is fast, cheap and simple method that could be used in detection of DS. Regarding possible false results detected for certain number of mosaic types, cytogenetic analysis should be used as a confirmatory test.
The aim of the study was to detect prevalence of MBL2 exon 1 (codons 52, 54 and 57) genetic polymorphism in postmenopausal women in Bosnia and Herzegovina and its possible role as genetic risk factor for susceptibility to occurrence of osteoporosis in this study group. Also, we investigated association between MBL serum concentrations and osteoporosis in postmenopausal women. Genetic codons' variations were determined by PCR-RFLP and MBL in serum was measured by ELISA method in 75 postmenopausal women (37 with osteoporosis and 38 apparently healthy, non-osteoporotic women serving as a control). Serum MBL levels were not significantly different between osteoporosis and control group (492 (37-565.1) and 522.6 (477-559.4) ng/mL respectively, p=0.206). Genotype frequencies were not significantly different (p=0.997) between the studied groups of postmenopausal women. Genotype frequencies A/A, A/0 and 0/0 in osteoporosis group were 0.576; 0.405; 0.018 and in control group 0.562; 0.412; 0.026, respectively. Frequencies of A and 0 allele were 0.78 and 0.22 in osteoporosis and 0.77 and 0.23 in control group. The results do not suggest association of functional polymorphism of MBL2 gene and MBL serum concentration with osteoporosis in postmenopausal females.
Endogenious opiod met-enkephalin throughout previous research manifested cytoprotective and anti-inflammatory effects. Previous research suggests that met-enkephalin has cytogenetic effects. Reducement in the frequency of structural chromosome aberrations as well as a suppressive effect on lymphocyte cell cycle is found. It also reduces apoptosis in the blood samples of the patients with immune-mediated diseases. Met-enkephalin exerts immunomodulatory properties and induces stabilization of the clinical condition in patients with multiple Sclerosis (MS). The goal of the present research was to evaluate met-enkephalin in vitro effects on the number and type of chromosome aberrations in the peripheral blood lymphocytes of patients with MS. Our research detected disappearance of ring chromosomes and chromosome fragmentations in the cultures of the peripheral blood lymphocytes treated with met-enkephalin (1.2 μg/mL). However, this research did not detect any significant effects of met-enkephalin on the reduction of structural chromosome aberrations and disappearance of dicentric chromosomes. Chromosomes with the greatest percent of inclusion in chromosome aberrations were noted as: chromosome 1, chromosome 2 and chromosome 9. Additionally, we confirmed chromosome 14 as the most frequently included in translocations. Furthermore, met-enkephalin effects on the increase of the numerical aberrations in both concentrations applied were detected. Those findings should be interpreted cautiously and more research in this field should be conducted.
The aim of this research was to assess the reactive changes of rat proximal tubules caused by gentamicin and the effect of relatively low doses of melatonin. 48 adult male Wistar rats were distributed into six groups of equal size which all received one of the following daily intraperitoneal injections: vehicle (5% ethanol in Ringer solution) during 11 days (C); gentamicin (80 mg/kg) during 8 days (G), two groups which concomitantly received gentamicin (80 mg/kg) during 8 days and melatonin in two different test doses (5 or 20 mg/kg) during 11 days (GM1, GM2) and two groups treated only with melatonin in two different doses (5 or 20 mg/kg) during 11 days (M1, M2). Histological analysis included qualitative and semi-quantitative light microscopy analysis of proximal tubules. Exogenous melatonin had no significant effect on the microstructure, independently of dosis. The changes of proximal tubules microstructure induced by gentamicin were expressed in the form of granulovacuolar degeneration, necrosis and desquamation. The grade of proximal tubular changes was smaller in animals who besides gentamicin received melatonin. Melatonin has a dose dependent protective effect on the structural alterations of proximal tubules of the kidney induced by gentamicin.
OBJECTIVE A significant number of patients with rheumatoid arthritis (RA) link the start of illness with psychological trauma or severe stress. Impaired mental health (IMH), defined as depression and anxiety with psychoneuroimmunological factors, can play a significant role in RA. The main objective of this research was to investigate the mutual correlation of IMH and RA activity, estimated by the laboratory and clinical parameters in RA patients. MATERIAL AND METHODS An open clinical prospective study that lasted for 6 months was designed. There were 72 patients included, 58 women and 14 men, aged 34 to 80 years and screened for mental health status. The study population was randomized following the Brief Symptoms Inventory (BSI) scale, comprised of 53 questions with a range from 0 (no symptoms) to 4 (severe). This mental test was done only once during the study. Following the results from the BSI scale, RA patients were divided into mentally stable and mentally unstable patients to investigate the influence of RA activity on mental health. The following laboratory and clinical parameters were analyzed: sex, age, erythrocyte sedimentation rate (ESR), rheumatoid factor (RF), C-reactive protein (CRP), anti-cyclic citrullinated peptide (anti-CCP) antibody, and disease activity score (DAS28). All RA patients did not express extra-articular manifestations or Sjögren's syndrome. The chi-square test, ANOVA, Pearson's coefficient, and IBM Statistics - SPSS v19 were used. RESULTS From a total of 72 RA patients, there were 44 mentally stable and 28 mentally unstable patients. All patients had either moderate or severe active disease. The only significant correlation of IMH and activity of RA was found in CRP and DAS28, but no significance was observed in ESR, RF, and anti-CCP. The DAS28 showed high disease activity with an average of 5.3 and CRP of 20.9 mg/L in patients with unstable mental health compared to stable mental health patients, where RA was associated with a moderate DAS average value of 4.35 and CRP of 14.1 mg/L. Depression and anxiety were found in all 28 (39%) RA patients. CONCLUSION Mentally unstable RA patients correlate more with severe disease activity, while mentally stable patients express moderate disease activity.
Nema pronađenih rezultata, molimo da izmjenite uslove pretrage i pokušate ponovo!
Ova stranica koristi kolačiće da bi vam pružila najbolje iskustvo
Saznaj više