The influence of fault reactivation on injection-induced dynamic triggering of permeability evolution

Mechanisms controlling fracture permeability enhancement during injection-induced and natural dynamic stressing remain unresolved. We explore pressure-driven permeability (k) evolution by step-increasing fluid pressure (p) on near-critically stressed laboratory fractures in shale and schist as representative of faults in sedimentary reservoirs/seals and basement rocks. Fluid is pulsed through the fracture with successively incremented pressure to first examine sub-reactivation permeability response that then progresses through fracture reactivation. Transient pore pressure pulses result in a permeability increase that persists even after the return of spiked pore pressure to the null background level. We show that fracture sealing is systematically reversible with the perturbing pressure pulses and pressure-driven permeability enhancement is eminently reproducible even absent shear slip and in the very short term (order of minutes). These characteristics of the observed fracture sealing following a pressure perturbation appear similar to those of the response by rate-and-state frictional healing upon stress/velocity perturbations. Dynamic permeability increase scales with the pore pressure magnitude and fracture sealing controls the following per-pulse permeability increase, both in the absence and presence of reactivation. However, initiation of the injection-induced reactivation results in a significant increase in the rate of permeability enhancement (dk/dp). These results demonstrate the role of frictional healing and sealing of fractures at interplay with other probable processes in pore pressure-driven permeability stimulation, such as particle mobilization

The influence of fault reactivation on injection-induced dynamic triggering of permeability evolution

Mechanisms controlling fracture permeability enhancement during injection-induced and natural dynamic stressing remain unresolved. We explore pressure-driven permeability (k) evolution by step-increasing fluid pressure (p) on near-critically stressed laboratory fractures in shale and schist as representative of faults in sedimentary reservoirs/seals and basement rocks. Fluid is pulsed through the fracture with successively incremented pressure to first examine sub-reactivation permeability response that then progresses through fracture reactivation. Transient pore pressure pulses result in a permeability increase that persists even after the return of spiked pore pressure to the null background level. We show that fracture sealing is systematically reversible with the perturbing pressure pulses and pressure-driven permeability enhancement is eminently reproducible even absent shear slip and in the very short term (order of minutes). These characteristics of the observed fracture sealing following a pressure perturbation appear similar to those of the response by rate-and-state frictional healing upon stress/velocity perturbations. Dynamic permeability increase scales with the pore pressure magnitude and fracture sealing controls the following per-pulse permeability increase, both in the absence and presence of reactivation. However, initiation of the injection-induced reactivation results in a significant increase in the rate of permeability enhancement (dk/dp). These results demonstrate the role of frictional healing and sealing of fractures at interplay with other probable processes in pore pressure-driven permeability stimulation, such as particle mobilization

Evaluation of the results of MOTAKK hepatitis C virus RNA genotyping and hepatitis delta virus external quality assessment programs during 2015-2016

Background/Aims: To evaluate the HCV RNA genotyping and HDV RNA tests that are performed in molecular microbiology laboratories in Turkey as part of a national external quality assessment programme, MOTAKK (Molekuler Tanida Kalite Kontrol) (English translation: Quality control in molecular diagnostics)

Prevalence of Vitamin D Deficiency and Hypervitaminosis D Among Adult Patients Admitted to the Tertiary Care Hospitals in Turkey

Objective: Vitamin D deficiency is a common health problem around the world. This study aimed to evaluate the nationwide prevalence of vitamin D status in tertiary care hospitals in Turkey

Real life experience of patients with locally advanced gastric and gastroesophageal junction adenocarcinoma treated with neoadjuvant chemotherapy: a Turkish oncology group study

Neoadjuvant chemotherapy (NACT) in gastroesophageal junction (GEJ) and gastric cancer (GC) was shown to improve survival in recent studies. We aimed to share our real-life experience of patients who received NACT to compare the efficacy and toxicity profile of different chemotherapy regimens in our country. This retrospective multicentre study included locally advanced GC and GEJ cancer patients who received NACT between 2007 and 2021. Relation between CT regimens and pathological evaluation were analysed. A total of 794 patients from 45 oncology centers in Turkey were included. Median age at the time of diagnosis was 60 (range: 18-86). Most frequent NACT regimens used were FLOT (65.4%), DCF (17.4%) and ECF (8.1%), respectively. In the total study group, pathological complete remission (pCR) rate was 7.2%, R0 resection rate 86.4%, and D2 dissection rate was 66.8%. Rate of pCR and near-CR (24%), and R0 resection (84%) were numerically higher in FLOT arm (p > 0.05). Patients who received FLOT had also higher chemotherapy-related toxicity rate compared to patients who received other regimens (p > 0.05). Median follow-up time was 16 months (range: 1-154 months). Estimated median overall survival (OS) was 58.4months (95% CI: 35.2-85.7) and disease-free survival (DFS) was 50.7 months (95% CI: 25.4-75.9). The highest 3-year estimated OS rate was also shown in FLOT arm (68%). We still do not know which NACT regimen is the best choice for daily practice. Clinicians should tailor treatment regimens according to patients' multifactorial status and comorbidities for to obtain best outcomes. Longer follow-up period needs to validate our results

Treatment outcomes and prognostic factors in patients with driver mutant non-small cell lung cancer and de novo brain metastases

Abstract Central nervous system (CNS) metastases can be seen at a rate of 30% in advanced stages for patients with non-small cell lung cancer (NSCLC). Growing evidence indicates the predictive roles of driver gene mutations in the development of brain metastases (BM) in recent years, meaning that oncogene-driven NSCLC have a high incidence of BM at diagnosis. Today, 3rd generation targeted drugs with high intracranial efficacy, which can cross the blood–brain barrier, have made a positive contribution to survival for these patients with an increased propensity to BM. It is important to update the clinical and pathological factors reflected in the survival with real-life data. A multi-center, retrospective database of 306 patients diagnosed with driver mutant NSCLC and initially presented with BM between between November 2008 and September 2022 were analyzed. The median progression-free survival (mPFS) was 12.25 months (95% CI, 10–14.5). While 254 of the patients received tyrosine kinase inhibitor (TKI), 51 patients received chemotherapy as first line treatment. The median intracranial PFS (iPFS) was 18.5 months (95% CI, 14.8–22.2). The median overall survival (OS) was 29 months (95% CI, 25.2–33.0). It was found that having 3 or less BM and absence of extracranial metastases were significantly associated with better mOS and iPFS. The relationship between the size of BM and survival was found to be non-significant. Among patients with advanced NSCLC with de novo BM carrying a driver mutation, long-term progression-free and overall survival can be achieved with the advent of targeted agents with high CNS efficacy with more conservative and localized radiotherapy modalities

Evaluation of the results of MOTAKK hepatitis C virus RNA genotyping and hepatitis delta virus external quality assessment programs during 2015-2016

Background/Aims: To evaluate the HCV RNA genotyping and HDV RNA tests that are performed in molecular microbiology laboratories in Turkey as part of a national external quality assessment programme, MOTAKK (Molekuler Tanida Kalite Kontrol) (English translation: Quality control in molecular diagnostics). Materials and Methods: Plasmas having different HCV RNA genotypes were used to prepare HCV genotype control sera. The HDV RNA main stock was prepared from patients with chronic delta hepatitis who had a significant amount of viral load detected, as per the WHO reference materials on viral load studies that were compiled for the purpose of developing HDV RNA control sera. Samples with different viral loads were prepared from this main stock by dilution. The prepared controls were delivered to the registered laboratories. The laboratories carried out the relevant tests and entered their results via the MOTAKK web page. External quality assessment (EQA) reports of the participants were uploaded to the website as well. Results: In total, there were 23 participating laboratories, out of which 20 exclusively performed HCV genotyping, and 15 and 16 only performed HDV RNA in 2015 and 2016, respectively. The success rate of the results of the HCV genotype was 56-96\% in 2015 and 30-95\% in 2016. The tube with a 30\% success rate had a recombinant type of HCV, therefore, it could not be detected in most of the laboratories. The HDV RNA results were evaluated qualitatively. Accordingly, HDV RNA detection rates of participant laboratories were 71-100\% in 2015 and 50-100\% in 2016. Conclusion: This study was the first national external quality control program in Turkey regarding HCV RNA genotyping and HDV RNA in the field of molecular microbiology, and it was implemented successfully

Evaluation of 2015-2016 MOTAKK HBV DNA and HCV RNA External Quality Assessment National Program Results

MOTAKK, as a national external quality control program has been launched to evaluate the molecular detection of viral infections including HBV DNA and HCV RNA in molecular microbiology diagnostic laboratories in Turkey. This program is prepared in compliance with ISO 17043:2010 (Conformity assessment general requirements for proficiency testing) standards, and aims to take the place of external quality control programs from abroad, contributing to standardization and accuracy of molecular diagnostic tests in our country. The aim of this study was to evaluate 2015 and 2016 results of the MOTAKK External Quality Control Program for HBV DNA and HCV RNA viral load. The calls were announced on the web page of MOTAKK (www.motakk.org). The quality control samples were sent to participating laboratories in 2015 and 2016. Main stocks were prepared from patients with chronic hepatitis B and C who had viral load detection with reference methods according to WHO reference materials for viral load studies to improve quality control sera. From these main stocks, samples with different viral loads were prepared from dilutions of plasma with HBV, HCV, HAV, HIV, Parvovirus B19 and CMV negative serologic markers. Quality control samples were sent to the participating laboratories along with the negative samples in the cold chain. The laboratories accomplished the related tests within 2-3 weeks and entered their results on the MOTAKK web page. These results were analysed according to ISO 13528 (Statistical methods for use in proficiency testing by interlaboratory comparison) and scoring reports were created by a software developed by MOTAKK and sent to participating labs. Each laboratory evaluated their own results in comparison with the other laboratory results, reassessed the tests via observing the distance from the mean result and the reference values. The number of laboratories participating in the HBV DNA and HCV RNA external quality control program was 70-73 in 2015-2016. Participants were able to comply with the program tools, registering, entering results and receiving the results reports problem. In HBV panel, 72.6-89.1% and 84.7-90.3% of the participant laboratories were in 1 standard deviation (SD) in 2015-2016, respectively. In HCV panel, 70.8-89.1% and 84.7-90.3% of the participant laboratories were in 1 SD in 2015-2016, respectively. A national external quality control program for HBV DNA and HCV RNA in Turkey has been prepared for the first time with this project and implemented successfully. All the data provided in the MOTAKK external quality control program final report, compensate all the data provided by the quality control program final reports from abroad; additionally, the report allows comparison of used technologies and commercial products

Treatment efficacy of ribociclib or palbociclib plus letrozole in hormone receptor-positive/HER2-negative metastatic breast cancer.

Background: Ribociclib, palbociclib and abemaciclib are currently approved CDK4/6 inhibitors along with aromatase inhibitors as the first-line standard-of-care for patients with hormone receptor-positive, HER2-negative metastatic breast cancer. Methods: The authors report retrospective real-life data for 600 patients with estrogen receptor- and/or progesterone receptor-positive and HER2-negative metastatic breast cancer who were treated with ribociclib and palbociclib in combination with letrozole. Results & conclusion: The results demonstrated that the combination of palbociclib or ribociclib with letrozole has similar progression-free survival and overall survival benefit in real life for the patient group with similar clinical features. Specifically, endocrine sensitivity may be a factor to be considered in the treatment preference

The prevalence of childhood psychopathology in Turkey: a cross-sectional multicenter nationwide study (EPICPAT-T).

Aim: The aim of this study was to determine the prevalence of childhood psychopathologies in Turkey