Gas seepage and seismogenic structures along the North Anatolian Fault in the eastern Sea of Marmara

We carried out a combined geophysical and gas-geochemical survey on an active fault strand along the North Anatolian Fault (NAF) system in the Gulf of İzmit (eastern Sea of Marmara), providing for the first time in this area data on the distribution of methane (CH4) and other gases dissolved in the bottom seawater, as well as the CH4isotopic composition. Based on high-resolution morphobathymetric data and chirp-sonar seismic reflection profiles we selected three areas with different tectonic features associated to the NAF system, where we performed visual and instrumental seafloor inspections, including in situ measurements of dissolved CH4, and sampling of the bottom water. Starting from background values of 2–10 nM, methane concentration in the bottom seawater increases abruptly up to 20 nM over the main NAF trace. CH4 concentration peaks up to ∼120 nM were detected above mounds related probably to gas and fluids expulsion. Methane is microbial (δ13CCH4: −67.3 and −76‰ versus VPDB), and was found mainly associated with pre-Holocene deposits topped by a 10–20 m thick draping of marine mud. The correlation between tectonic structures and gas-seepages at the seafloor suggests that the NAF in the Gulf of İzmit could represent a key site for long-term combined monitoring of fluid exhalations and seismicity to assess their potential as earthquake precursors

An example of secondary fault activity along the North Anatolian Fault on the NE Marmara Sea Shelf, NW Turkey

Seismic data on the NE Marmara Sea Shelf indicate that a NNE-SSW-oriented buried basin and ridge system exist on the sub-marine extension of the Paleozoic Rocks delimited by the northern segment of the North Anatolian Fault (NS-NAF), while seismic and multi-beam bathymetric data imply that four NW-SE-oriented strike-slip faults also exist on the shelf area. Seismic data indicate that NW-SE-oriented strike-slip faults are the youngest structures that dissect the basin-ridge system. One of the NW-SE-oriented faults (F1) is aligned with a rupture of the North Anatolian Fault (NAF) cutting the northern slope of the Cinarcik Basin. This observation indicates that these faults have similar characteristics with the NS-NAF along the Marmara Sea. Therefore, they may have a secondary relation to the NAF since the principle deformation zone of the NAF follows the Marmara Trough in that region. The seismic energy recorded on these secondary faults is much less than that on the NAF in the Marmara Sea. These faults may, however, produce a large earthquake in the long term

Identification of Cryptococcus antigen in human immunodeficiency virus-positive Turkish patients by using the Dynamiker® lateral flow assay

PubMedID: 31344286Cryptococcus neoformans causes life-threatening meningoencephalitis, particularly in human immunodeficiency virus (HIV)-positive individuals with low CD4 levels ('100 cells/µL). Although the burden of cryptococcal meningoencephalitis (CM) in Turkey is low (0.13 cases per 100 000 persons), asymptomatic individuals at risk of cryptococcosis should be screened for antigenemia to prevent the disease and/or promote early CM diagnosis. A lateral flow assay (LFA) is used to detect Cryptococcus antigen (CrAg) in cerebrospinal fluid and serum. We determined Cryptococcus antigenemia prevalence in serum samples of HIV-positive and HIV-negative adult patients by using Dynamiker® CrAg-LFA, a point-of-care dipstick test. Patients’ demographic data, CD4 count, HIV-RNA levels and anti-retroviral therapy status were recorded. CrAg was detected in 28 (11%) of 254 HIV-positive patients screened but not in 100 HIV-negative control individuals; a significant difference was observed in the CrAg-LFA positivity rate between HIV-positive and HIV-negative groups (x2 = 11.970; P '.05). In CrAg-positive patients, the median CD4 level was 666 cells/µL (115-1344 cells/µL), with a median viral load of 23 copies/mL (0-3.69 × 106 copies/mL). In HIV-positive CrAg-negative patients, the median CD4 level was 633 cells/µL (31-2953 cells/µL) and the median viral load was 12 copies/mL (0-1.95 × 106 copies/mL; P '.05). Results indicate that HIV-positive patients with both low ('200 cells/µL) and high ('200 cells/µL) CD4 counts should be screened for asymptomatic cryptococcal antigenemia. HIV-associated asymptomatic cryptococcosis is not uncommon in Turkey, which warrants systematic screening. Updated strategies for CM prevention among HIV-positive patients should be used even in non-endemic countries. © 2019 Blackwell Verlag Gmb

Effect of ketamine, thiopental and ketamine–thiopental combination during electroconvulsive therapy for depression

Objective: We aimed to evaluate the effect of anaesthesia with thiopental (4 mg kg-1), ketamine (1 mg kg-1) and ketamine-thiopental (1 mg kg-1 and 4 mg kg-1, respectively) combination during electroconvulsive therapy (ECT) on the Hamilton Depression Rating Scale (HDRS) and Hamilton Anxiety Rating Scale (HAM-A) and haemodynamic variables in patients with resistant major depression. Methods: Patients with HDRS scores above 17 were included. The patients were randomly divided into three groups according to the anaesthesia used. Group 1 was given thiopental (4 mg kg-1), Group 2 was given ketamine (1 mg kg-1) and Group 3 was given ketamine (1 mg kg-1) and thiopental (4 mg kg-1). Succinylcholine (1 mg kg-1) was administered in all patients for muscle relaxation. HDRS and HAM-A scores were evaluated before ECT, after 3, 6. ECT and after the final ECT. Systolic and diastolic blood pressures, heart rates and oxygen saturations were recorded before and after anaesthesia induction and after the ECT procedure. Seizure duration was recorded. Results: Fifty-eight patients were included in the study. Thirty (52%) patients were male and 28 (48%) were female. The mean age was 42.7±15.8 years in Group 1, 44.8±11 years in Group 2 and 38.6±6.8 years in Group 3. In all groups, HDRS scores were reduced compared with the baseline values. There was no statistical significant difference between the groups regarding HDRS scores. HAM-A scores were higher in Group 2 and Group 3. Systolic and diastolic blood pressures and heart rate values were lower in Group 1 and the difference was statistically significant. Conclusion: In this study, anaesthesia induced with thiopental, ketamine and thiopental–ketamine combination was observed to not result in a difference in ECT for patients with treatment-resistant depression. Ketamine at a dose of 1 mg kg-1 given just before ECT did not enhance the antidepressant effect of ECT; however, anxiety scores were increased with ketamine application. © 2015 by Turkish Anaesthesiology and Intensive Care Society

Molecular epidemiology of carbapenem-resistant Klebsiella pneumoniae at a Turkish centre: Is the increase of resistance a threat for Europe?

PubMedID: 28743652Objectives In recent years, carbapenem-resistant Klebsiella pneumoniae (CRKP) have become an important threat to hospitalised patients. This study aimed to identify the genetic mechanisms of carbapenem resistance in CRKP isolated from patients in a Turkish centre. Methods During 2013–2014, a total of 98 K. pneumoniae isolated from patients at Çukurova University Balcalı Hospital (Adana, Turkey) determined phenotypically as resistant to carbapenems were screened genotypically for the presence of carbapenemase enzymes by multiplex PCR. Results Of the 98 patients for whom genetic investigation was made, 93 (94.9%) were adults, 56 (57.1%) were male and 81 (82.7%) were diagnosed as infected. The mean and median age were 51.8 ± 20.5 years and 55 years (range 1–89 years), respectively. The nosocomial infection rate was 87.8% (86/98). The mortality rate was 41.8% (41/98). Fifty-eight patients (59.2%) were admitted to intensive care units. Of the 12 non-nosocomial infections, 5 (41.7%) originated from the inpatient clinic of the urology department. The mean and median hospital length of stay (LOS) were 20.7 ± 20.8 days and 17 days (range 0–90 days), respectively. The most common carbapenemase gene detected was blaOXA-48 (74.5%), followed by blaVIM (45.9%) and blaSME (37.8%). The blaNDM gene was detected in 20 isolates (20.4%). The most effective antibiotics were tigecycline and colistin, with susceptibility rates of 87.5% and 74.3%, respectively. Conclusions Multiple resistance mechanisms were present in CRKP isolates in Turkey. Most of the isolates harboured blaOXA-48, blaVIM and blaSME genes; meanwhile, the rate of 20.4% for blaNDM is alarming. © 2017 International Society for Chemotherapy of Infection and Cance

The Importance of Parameters: MPV, MPV/Thrombocyte Ratio and Neutrophil/Lymphocyte Ratio in Sorafenib Treatment Response of Patients with Hepatocellular Cancer

PubMedID: 28691138[No abstract available

Factors affecting epilepsy prognosis in patients with tuberous sclerosis

PubMedID: 30673834Purpose: We aimed to determine the characteristics of epileptic seizures that significantly affect the cognitive functions of 83 patients followed with tuberous sclerosis complex (TSC), their resistance to treatment and risk factors causing this resistance. Materials-methods: In order to determine the prognosis, the seizure-free/seizure-controlled group and the group with refractory seizures were compared. In addition, risk factors affecting cognitive functions in the patients were determined. Results: There was a statistical significance between the presence of a history of seizures in the neonatal period, the age of onset of seizures being less than 2 years of age, autism, status epilepticus, Lennox-Gastaut syndrome (LGS), presence of infantile spasm, generalization of the electroencephalography (EEG) findings, the number of tubers in cerebral imaging being more than three and refractory seizures (p < 0.05). Statistically significant relationship was found between presence of a history of seizures in the neonatal period, the age of onset of seizures, autism, LGS, presence of infantile spasm, presence of status epilepticus history, history of using more than three antiepileptic drugs, generalization of EEG findings, presence of SEGA in cerebral imaging, number of tubers being more than three and the patient’s mental retardation (p < 0.05). Conclusion: In logistic regression analysis, the age of the seizure onset being less than 2 years of age, the presence of autism and number of tubers being more than three in cerebral magnetic resonance imaging (MRI) are determined to be the risk factors that most likely to increase the seizures to be more resistant. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature

Is losartan a promising agent for the treatment of type 1 diabetes-induced testicular germ cell apoptosis in rats?

Background: Diabetes mellitus (DM) is common metabolic disease that poses a major risk to public health and fertility. Previous studies indicate that DM may cause male infertility by triggering oxidative stress and germ cell apoptosis in the testis. Due to the undesirable effects of known antidiabetic drugs, scientists have begun to investigate the use of alternative drugs to control infertility complications observed in men. In this context, present study aimed to investigate the possible antiapoptotic effect of losartan against DM-induced testicular germ cell apoptosis. Methods and results: Expreimental DM model was induced by intraperitoneal injection of streptozocin (STZ, 55 mg/kg) to 28 rats, which were then randomly assigned to 4 groups; 1 mL saline solution was given to DM + saline group by oral gavage, 5 mg/kg/day oral losartan was given to DM + low-dose losartan, 20 mg/kg/day oral losartan was given to DM + mid-dose losartan and, 80 mg/kg/day oral losartan was given to DM + high-dose losartan group for 4 weeks. Bax, Bcl-2 and cleaved-Caspase 3 immunoexpression, terminal-deoxynucleotidyl transferase dutp nick end labeling (TUNEL), Annexin-V and Real Time PCR analyses performed to evaluate antiapoptotic effects of losartan on diabetic rats’ testis. In addition, biochemical analyzes carried out to evaluate change in oxidative stress. Conclusion: The results showed that losartan may have dose-related antiapoptotic effects on rats’ testis via decreasing oxidative stress. © 2022, The Author(s), under exclusive licence to Springer Nature B.V.This study was supported by the Ege University Research Fund [grant number 16-TIP-092 (to Altuğ Yavaşoğlu)].Ege University Research Foundation: 16-TIP-09