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Disruption of Biofilm Formation and Quorum Sensing in Pathogenic Bacteria by Compounds from Zanthoxylum Gilletti (De Wild) PG Waterman
No full textMicrobial resistance is facilitated by biofilm formation and quorum-sensing mediated processes. In this work, the stem bark (ZM) and fruit extracts (ZMFT) of Zanthoxylum gilletii were subjected to column chromatography and afforded lupeol (1), 2,3-epoxy-6,7-methylenedioxyconiferyl alcohol (3), nitidine chloride (4), nitidine (7), sucrose (6) and sitosterol-beta-D-glucopyranoside (2). The compounds were characterized using MS and NMR spectral data. The samples were evaluated for antimicrobial, antibiofilm and anti-quorum sensing activities. Highest antimicrobial activity was exhibited by compounds 3, 4 and 7 against Staphylococcus aureus (MIC 200 mu g/mL), compounds 3 and 4 against Escherichia coli (MIC = 100 mu g/mL) and compounds 4 and 7 against Candida albicans (MIC = 50 mu g/mL). At MIC and sub-MIC concentrations, all samples inhibited biofilm formation by pathogens and violacein production in C. violaceum CV12472 except compound 6. Good disruption of QS-sensing in C. violaceum revealed by inhibition zone diameters were exhibited by compounds 3 (11.5 +/- 0.5 mm), 4 (12.5 +/- 1.5 mm), 5 (15.0 +/- 0.8 mm), 7 (12.0 +/- 1.5 mm) as well as the crude extracts from stem barks (16.5 +/- 1.2 mm) and seeds (13.0 +/- 1.4 mm). The profound inhibition of quorum sensing mediated processes in test pathogens by compounds 3, 4, 5 and 7 suggests the methylenedioxy- group that these compounds possess as the possible pharmacophore
Paleoseismology of the Ganos segment; the western extend of the North Anatolian Fault (Turkey)
No full textThe Ganos fault that ruptured on 9 August 1912 (Mw: 7.4) is the westernmost inland segment of the North Anatolian fault (NAF). Here, the Ganos fault is bounded at its two tips with offshore faults segments, in the Sea of Marmara to the east and the Gulf of Saros to the west in the North Aegean Trough. Therefore, the paleoseismology of the 45-km-long inland fault is of importance to the seismic hazard analysis related to offshore active faults and in particular for the seismic gap in the Marmara Region. Earlier studies have established an earthquake chronology for the western and eastern inland tips of the Ganos fault. Here, we extend the paleoseismic studies toward the central segment. Three trenches at Yörgüç have revealed evidence for two faulting events, possibly post-1669 CE ±30 years, which can be correlated to the 1659 or 1766, and the 1912 historical earthquakes. At Yeniköy, we determined an offset of 46 ± 1 m and 47 ± 1 m on a stream channel and a ridge-crest, respectively. In two trenches we determined two faulting events for the last 1000 years and seven events for the last 3500 years. In trench T5, the base of the displaced stream channel provides a calibrated date of 829–591 BCE. Using the 46 ± 1 m right-lateral displacement, we calculate a slip rate of 16.9 ± 0.7 mm/year for the last 2732 ± 119 years. A combined analysis with earlier paleoseismic studies on the Ganos fault suggests that the historical earthquakes of 1912, 1766b or 1659, 1354 or 1343a, and 1063 ruptured the entire inland fault section. In such a case, the recurrence interval for this section of the NAF corresponds to 283 ± 81 years. Combining earlier estimations, we suggest an average slip rate of 17.1 ± 0.9 mm/year for the last 2700 years and observe a characteristic slip behavior of 4.5 to 5 m per event for this section of the North Anatolian plate boundary fault
Comparison of the electrocardiographic findings, heart rates, cloacal temperatures, respiratory rates, and anaesthetic effects of medetomidine- ketamine and detomidine-ketamine combination in the buzzards (Buteo buteo)
No full textAim of the present study was to compare the electrocardiographic findings, heart rate, cloacal tem-perature, respiratory rate, and anaesthetic effects of medetomidine-ketamine to detomidine-ketamine in buzzards. Fourteen buzzards of unknown sex and age and weighing a mean +/- standart deviation (SD) of 789.29 +/- 82.97 g were included in the study. The buzzards were randomly assigned to two groups: MK group (0.1 mg kg-1 medetomidine and 10 mg kg-1 ketamine 10 minutes after medetomidine application) and group DK (0.3 mg kg-1 detomidine and 10 mg kg-1 ketamine 10 minutes after medetomidine application). Heart rates (HR), respiratory rates (fR), and cloacal temperatures (CT) were recorded before administration of any drug (0) and then 5 and 10 minutes after medetomidine and 5, 10, 15, 30, 45, 60 minutes after ketamine. At this point, atipamezole (0.5 mg/kg, IM) was administered and measurement recorded at 5, 10 and 15 minutes. Serum electrolyte and blood gases were measured before and during anesthesia. Elec-trocardiogram was recorded before and during anesthesia. Distribution and suitability of the data were evaluated by the Shapiro-Wilks test. Statistical tests were performed via two-way variance analysis in repeated measures, and multiple comparisons were corrected with the post-hoc Generalized Linear Model (GLM). Differences were considered to be statistically significant if p < 0.05. Onset of anesthesia time was 4.1 +/- 2.3 and 3.9 +/- 1.3 minutes (mean +/- standard deviation) in groups MK and DK, respectively. Reflexes (righting reflex, toe pinch reflex, feather plucking reflex, palpebral reflex) disappeared studied in both groups during anesthesia. HR,fR , and CT were significantly decreased in both groups (p < 0.001). Baseline blood gases values showed significantly increases in pCO2 and HCO3 and decreases in pH and pO2 during anesthesia in both groups (p < 0.05). In conclusions medetomidine-ketamine and detomidine-ketamine combinations were both sufficient to provide desired level of anesthesia, analgesia and muscle relaxation
Stroke and bleeding risks according to age caterogories in patients on edoxaban
No full textStroke and bleeding risks..
The prognostic value of P53 index in predicting the recurrence of early low-risk endometrial cancer
No full textAim: We aimed to clarify the clinical value of P53 index in patients with early low-risk endometrial cancer (EC) and find an optimal cut-off value of P53 index for predicting the recurrence of these patients. Methods: The clinicopathological data of 157 patients with early low-risk EC (stage 1A with grade 1 or 2 endometrioid EC) were analyzed. The optimal cut-off value of the P53 index was calculated by the receiver operating characteristic curve analysis and Youden index. Cox regression model was used to evaluate the independent prognostic predictors of recurrence of EC. Then all patients were divided into two groups according to the optimal cut-off value of the P53 index. Differences of the clinicopathological parameters between the two groups were compared. Results: Multivariate analysis showed age PR (p = 0.020) and P53 (p = 0.001) were independent prognostic factors for the recurrence of EC. The value of P53 index was found to be the optimal cut-off point of 17.5% in estimating the recurrence of EC. The 5-year recurrence-free survival rates of patients in the low P53 index group (<17.5%) and the high P53 index group (≥17.5%) were 94.6% and 65.4% (p < 0.001). Conclusion: It has been revealed that the P53 index is a prognostic factor for recurrence in early low-risk EC. The optimal cut-off value of P53 index may contribute to the postoperative individualized treatment options for early low-risk EC patients
Evaluation of Auditory Temporal Discrimination Thresholds in Migraine Patients
No full textIntroduction: Although vestibular migraine is well defined, the effects of migraine on the auditory system have not been clearly identified yet. The aim of this study was to determine the effect of migraine on the auditory system. Methods: Migraine patients without hearing loss were included in the study. Group 1 consisted of patients with migraine pain, group 2 consisted of patients with migraine in the interictal period, and group 3 consisted of healthy volunteers with similar demographic characteristics to groups 1 and 2. Random gap detection test was applied to all 3 groups. Additionally, group 2 and group 3 patients were evaluated with the auditory cortical potentials and the mismatch negativity test. Results: There was a statistically significant difference between the 3 groups in the random gap detection test. There was no statistically significant difference in auditory cortical potentials between group 2 and group 3; however, a statistically significant difference was found between the groups in terms of mismatch negativity test latency. Conclusion: An auditory pathway may be affected in migraine patients, although hearing tests are normal. This interaction continues between attacks, being more evident during the pain period. Therefore, disorders of hearing or speech perception in migraine patients should be evaluated by further audiological tests
Comparison of Methods Used in Detection of DIF in Cognitive Diagnostic Models with Traditional Methods: Applications in TIMSS 2011
No full textThis study aims to compare the Wald test and likelihood ratio test (LRT) approaches with Classical Test Theory (CTT) and Item Response Theory (IRT) based differential item functioning (DIF) detection methods in the context of cognitive diagnostic models (CDMs), using the TIMSS 2011 dataset as a retrofitting study. CDMs, which have a significant potential when determining the DIF and their contribution to validity, can give confidence under the strong methodological background condition is met. Therefore, it is hoped that this study will contribute to the literature to ensure the correct usage of CDMs and evaluate the compatibility of these new approaches with traditional methods. According to the analysis results, thirty-one items showed differences between the cognitive diagnosis assessments and the traditional methods. The item with the largest DIF was found in the Raju Unsigned Area Measures technique in IRT, whereas the item with the lowest DIF was found in the Wald test technique developed for CDMs. In general, the analyses show that methods not based on CDMs detect more items with DIF, but the Wald test and LRT methods based on CDMs detect fewer items with DIF. This study conducted DIF analyses to determine the test's psychometric properties within the framework of CDMs rather than the source of the bias. Researchers can take the study one step further and make more specific assessments about the items' bias regarding the test structure, test scope, and subgroups. In addition, DIF analyses in this study were carried out using only the gender variable, and researchers can use different variables to conduct studies specific to their purpose
Experimental Investigation of a Concentrating Bifacial Photovoltaic/Thermal Heat Pump System with a Triangular Trough
No full textThe heat absorbed by the heat transfer fluid for cooling a concentrated photovoltaic thermal (CPVT) solar collector can be used for purposes such as residential heating and cooking. Because of the combined production of heat and power, these systems are proposed for individual or commercial use in rural areas. In this study, a hybrid system was proposed to increase the electrical efficiency of the system. Experiments were conducted in winter conditions. Two operational modes were compared, namely a CPVT system with HP (HP-CPVT) and without HP (CPVT). The evaporator of the heat pump was settled inside the triangular trough receiver. The effects of cooling the PV system with a heat pump in the bifacial CPVT system on the electrical and thermal energy efficiencies were investigated. The electricity and thermal energy efficiencies of the CPVT system were calculated as 12.54% and 38.37% in the HP-CPVT system, respectively, and 10.05% and 81.97% in the CPVT system, respectively. The electrical exergy efficiencies of the CPVT system with and without HP were 14.65% and 10.73%, respectively. The thermal exergy efficiencies of the CPVT system with and without HP were 82.47% and 85.63%, respectively. The thermal heat obtained from the HP-CPVT system can be used for heating needs. Thus, the bifacial HP-CPVT system was an example of the micro-CHP system
Birth outcomes in pregnant women with epilepsy: A Nationwide multicenter study from Türkiye
No full textObjective: The present study was aimed at investigating the effects of anti-seizure medications (ASMs), patient demographic characteristics, and the seizure type and frequency on the development of congenital malformations (CMs) in the infants of pregnant women with epilepsy (PWWE). Methods: PWWE followed up at the neurology outpatient clinic of 21 centers between 2014 and 2019 were included in this prospective study. The follow-up of PWWE was conducted using structured, general pregnant follow-up forms prepared by the Pregnancy and Epilepsy Study Committee. The newborns were examined by a neonatologist after delivery and at 1 and 3 months postpartum. Results: Of the infants of 759 PWWE, 7.2% had CMs, with 5.6% having major CMs. Polytherapy, monotherapy, and no medications were received by 168 (22.1%), 548 (72.2 %), and 43 (5.7 %) patients, respectively. CMs were detected at an incidence of 2.3% in infants of PWWE who did not receive medication, 5.7% in infants of PWWE who received monotherapy, and 13.7% in infants of PWWE who received polytherapy. The risk of malformation was 2.31-fold (95% confidence interval (CI): 1.48–4.61, p <.001) higher in infants of PWWE who received polytherapy. Levetiracetam was the most frequently used seizure medication as monotherapy, with the highest incidence of CMs occurring with valproic acid (VPA) use (8.5%) and the lowest with lamotrigine use (2.1%). The incidence of CMs was 5% at a carbamazepine dose <700 mg, 10% at a carbamazepine dose ≥700 mg, 5.5% at a VPA dose [removed
Is the number of non-native species in the European Union saturating?
No full textBackground: Non-native species can have significant negative impacts on the environment, economies, and amongst others, also human Non-native species can have significant negative impacts on the environment, economies, and human Non-native species can have significant negative impacts on the environment, economies, and human well-being, among other factors. Globalisation and economic incentives have substantially facilitated the growth in the numbers of newly recorded non-native species in the European Union. The European Union’s diversity in terms of political and socio-economic differences across member states may have contributed to the introduction of non-native species. Results: Data reported in the Alien Species First Record Database, however, suggests a decreasing trend in the number of non-native species recorded over the past three decades. InvaCost, a database of non-native species with economic impacts, similarly shows increasing numbers of reported non-native species with costs until the 2010s, which were, however, followed by a plateauing and ultimately decline. Although the recent trends in non-native species reports may be affected by a lag time in reporting and data allocation as well as possibly a disparity in research efforts, their impacts persist, leading to a growing ecological but also economic burden. We further identified substantial spatial differences as western European member states generally reported higher numbers of non-native species and non-native species with monetary impacts. Conclusions: Without improved actions, biological invasions and their associated impacts will continue to rise, degrading natural capital and hampering sustainable development and sustainability targets. Therefore, improved coordinated efforts across the European Union are necessary to improve reporting of non-native species and a centralized collation of data through accessible databases should be considered