PubMed İndeksli Yayınlar Koleksiyonu

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2-[(2-Bromo-phen-yl)imino-meth-yl]-6-methyl-phenol
(int Union Crystallography, 2010) Karadag, Asli Tosyali; Atalay, Sehriman; Genc, Hasan
In the title compound, C14H12BrNO, is a Schiff base which adopts the phenol-imine tautomeric form in the solid state. The dihedral angle between the two aromatic rings is 34.26 (9)degrees and an intramolecular O-H center dot center dot center dot N hydrogen bond generates an S(6) ring.
2-[(E)-2-Hy-droxy-5-(trifluoro-meth-oxy)benzyl-idene-amino]-4-methyl-phenol
(int Union Crystallography, 2011) Karadag, Asli Tosyali; Atalay, Sehriman; Genc, Hasan
The title compound, C15H12F3NO3, is a Schiff base which adopts the cis-quinoid form in the solid state. The dihedral angle between the least-squares planes of the benzene rings being 3.6 (1)degrees. The F atoms of the -CF3 group are disordered over two sets of sites with refined occupancies of 0.61 (5) and 0.39 (5). An intramolecular N-H center dot center dot center dot O hydrogen bond occurs. The crystal structure is stabilized by intermolecular O-H center dot center dot center dot O hydrogen bonds.
3,5-Dibenzoyl
(int Union Crystallography, 2009) Sahin, Zarife Sibel; Isik, Samil; Sener, Ahmet; Tan, Meltem
In the crystal structure of the title compound, C26H27NO3, a one-dimensional network of C-H center dot center dot center dot O hydrogen bonds and pi-ring interactions is responsible for crystal stabilization. Intermolecular hydrogen bonds and C-H center dot center dot center dot pi interactions produce R-2(2)(10), R-4(4)(27) and R-4(4)(29) rings.
A 5 Years Follow-Up for Ischemic Cardiac Outcomes in Patients With Carotid Artery Calcification on Panoramic Radiographs Confirmed by Doppler Ultrasonography in Turkish Population
(British inst Radiology, 2020) Akkemik, Ozlem; Kazaz, Hakki; Tamsel, Sadik; Dundar, Nesrin; Sahinalp, Sahin; Ellidokuz, Hulya
Objective: To evaluate the diagnostic accuracy of digital panoramic radiograph (DPR) for detection of carotid artery calcification (CAC) confirmed by Doppler Ultrasonography (DUSG) and to clarify the relationship between between CAC identified by DPR and cardiovascular events through a 5 year follow-up period. Methods: Of 3600 consecutive patients examined, 158 patients presented with CAC as detected by DPR. The final study group was composed of 96 patients who had CAC confirmed by DUSG or CT angiogram. The control group was composed of 62 patients who has normal DUSG. The end point of the study was the occurrence of any cardiovascular event. Results: 72 (75%) of the 96 patients with CAC confirmed by DUSG (16 patients had significant stenosis) had bilateral and 24 (25%) had unilateral CAS as detected by DUSG. There was a low agreement between the examination results with a kappa value of 0.488 (p < 0.005) for calcification. Study data revealed that smoking, chronic obstructive pulmonary disease (COPD), diabetes mellitus (DM) and diastolic hypertension were significantly more common in patients with CAC than the control group (p < 0.05). During the follow-up period, 13 subjects had myocardial infarction and 1 subject died; in the control group, 1 patient died after MI and 1 patient died of a non-cardiac event. Conclusion: Patients with CAC detectable by DPR concomitant with COPD, DM, smoking or diastolic hypertension are more likely to suffer from vascular events. Therefore, patients with detectable carotid plaque in DPR require referral to a cardiovascular surgery clinic for further investigations.
5-fluoro/(trifluoromethoxy)-2-indolinone Derivatives With Anti-Interleukin Activity
(Wiley-v C H verlag Gmbh, 2023) Soylu-Eter, Ozge; Sevincli, Zekiye Seyma; Ersoy, Betul; Hasanusta, Bahar; Gatfar, Ugur; Lack, Nathan A.; Karali, Nilgun
The pro-inflammatory cytokine interleukin-1 (IL-1) drives the pathogenesis of several inflammatory diseases. Recent studies have revealed that 2-indolinones can modulate cytokine responses. Therefore, we screened several 2-indolinone derivatives in preliminary studies to develop agents with anti-IL-1 activity. First, the putative efficacies and binding interactions of 2-indolinones were evaluated by docking studies. Second, previously synthesized 5-fluoro/(trifluoromethoxy)-1H-indole-2,3-dione 3-(4-phenylthiosemicarbazones) (compounds 47-69) which had the highest inhibitory effect in the screening were evaluated for inhibitory effects on the IL-1 receptor (IL-1R). Compounds 52 (IC50 = 0.09 mu M) and 65 (IC50 = 0.07 mu M) were selected as lead compounds for the subsequent synthesis of new derivatives. The novel 5-fluoro/(trifluoromethoxy)-1H-indole-2,3-dione 3-(4-phenylthiosemicarbazones) (compounds 70-116) were designed, synthesized, and in vitro studies were completed. The compounds 76, 78, 81, 91, 100, 105, and 107 tested showed nontoxic inhibitory effects on IL-1R-dependent responses in the range of 0.01-0.06 mu M and stronger than the lead compounds 52 and 65. In vitro and in silico findings showed that compounds 78 (IC50 = 0.01 mu M) and 81 (IC50 = 0.02 mu M) had the strongest IL-1R inhibitory effects and the most favorable drug-like properties. Molecular modeling studies of the compounds 78 and 81 were carried out to determine the possible binding interactions at the active site of the IL-1R. Novel 5-fluoro/(trifluoromethoxy)-2-indolinone derivatives were designed and synthesized based on in silico and preliminary in vitro test results from lead compounds. All compounds tested displayed nontoxic IL-1 receptor inhibitory effects at IC50 values in the range of 10 nM to 13 mu M, and seven compounds showed inhibitory responses stronger than the lead compounds at 0.01-0.06 mu M.image
7-Acetoxyhorminone From Salvia Multicaulis Vahl. as Promising Inhibitor of 3-Hydroxy Coenzyme a (hmg-Coa) Reductase
(Mdpi, 2022) Yigitkan, Serkan; Ertas, Abdulselam; Salmas, Ramin Ekhteiari; Firat, Mehmet; Orhan, Ilkay Erdogan
3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase is a key enzyme involved in cholesterol biosynthesis and one of the most important targets for the treatment of hypercholesterolemia. A limited number of studies on the HMG-CoA reductase inhibitory potential of natural products are available. Thus, in the current study, we aimed to test the HMG-CoA reductase inhibitory capacity of extracts from the roots and aerial parts of Salvia multicaulis Vahl., through activity-guided isolation. Our findings revealed that the root extract prepared with dichloromethane-acetone (1:1) showed the highest inhibition (71.97 +/- 0.37%) at 100 mu g/mL. The extract was then initially fractionated by column chromatography and the obtained fractions were monitored by thin layer chromatography. Fractions which were similar to each other were combined and a total of 15 fractions were obtained. Further conventional chromatographic studies were carried out on the active fractions. Based on these fractions, 10 known compounds, comprising 9 terpenes and 1 steroid derivative in total, were isolated and their structures were verified by a combination of IT-TOF-MS, and 1D and 2D NMR techniques. According to the enzyme inhibition data of the identified compounds, 7-acetoxyhorminone exerted the highest inhibition (84.15 +/- 0.10%, IC50 = 63.6 +/- 1.21 mu g/mL). The molecular docking experiments on 7-acetoxyhorminone and horminone indicated that both compounds strongly bind to the active site of the enzyme.
Abnormal Left Ventricular Longitudinal Functional Reserve Assessed by Exercise Pulsed Wave Tissue Doppler Imaging in Patients With Subclinical Hypothyroidism
(Endocrine Soc, 2009) Akcakoyun, Mustafa; Kaya, Hasan; Kargin, Ramazan; Pala, Selcuk; Emiroglu, Yunus; Esen, Ozlem; Esen, Ali Metin
Background: Response of systolic and diastolic velocities of mitral annulus to exercise in patients with subclinical hypothyroidism (SCH) has not been explored previously. We sought to investigate whether SCH is associated with abnormal left ventricular (LV) longitudinal function reserve to exercise. Methods: Mitral annular systolic (S') and early diastolic (E') velocities were measured at rest and during supine bicycle exercise using tissue Doppler echocardiography (TDE) in 23 patients with newly diagnosed SCH and 25 controls. LV diastolic and systolic longitudinal function reserve indices were calculated. Results: There were no significant differences in mitral inflow velocities at rest between groups except for LV end-diastolic dimension and LV end-systolic dimension, which were higher in the control group. E' and S' at rest were also similar between the groups. However, S' (9.8 +/- 1.5 vs. 11.3 +/- 1.5 cm/sec at 25 W, P = 0.001; and 11.3 +/- 1.8 vs. 13.1 +/- 1.8 cm/sec at 50 W, P = 0.001) and E' (13.8 +/- 1.4 vs. 15.7 +/- 1.6 cm/sec at 25 W, P = 0.001; and 15.6 +/- 1.6 vs. 18.2 +/- 1.5 cm/sec at 50 W, P < 0.001) during exercise were significantly lower in patients with SCH. Longitudinal systolic and diastolic function reserve indices were significantly lower in patients with SCH (systolic index, 1.4 +/- 0.9 vs. 2.5 +/- 0.9 cm/sec at 25 W, P = 0.001; and 2.7 +/- 1.3 vs. 4.1 +/- 1.2 cm/sec at 50 W, P = 0.001; diastolic index, 2.3 +/- 1.3 vs. 3.6 +/- 1.5 cm/sec at 25 W, P = 0.003; and 3.9 +/- 1.6 vs. 5.9 +/- 1.3 cm/sec at 50 W, P < 0.001). Conclusion: Assessment of LV longitudinal functional reserve with exercise using TDE appears to be helpful in identifying early myocardial dysfunction in SCH. (J Clin Endocrinol Metab 94: 2979-2983, 2009)
Absence of Frontal Sinus in Turkish Individuals
(Yonsei University College of Medicine, 2003) Aydinlioǧlu, A.; Kavakli, A.; Erdem, S.
The frontal sinus has been used for personal identification since the early part of the 20th century as a result of its tremendous interindividual variation. The frontal sinus is present in approximately 90% of adults. However, some populations have a higher proportion of people without a frontal sinus. This study investigated the frequency of the absence of frontal sinuses in Turkish individuals. The present study was performed retrospectively on the CT scans of the paranasal sinuses in the axial and coronal planes from a series of 1200 cases. A bilateral absence and a unilateral absence of sinuses were found in 3.8% and 4.8% of cases, respectively. The clinical significance of the frontal sinuses and their absence are also discussed.
Absence of Right Superior Vena Cava and Aortic Annular Hypoplasia in a Patient With Turner's Syndrome
(Wiley, 2005) Kutay, V; Yakut, C
Cardiovascular abnormalities are frequently encountered in patients with Turner's syndrome. These include coarctation of the aorta, bicuspid aortic valve, aortic root dilatation, atrial and ventricular septal defects, but absence of the right superior vena cava (SVC) in visceroatrial situs solitus is extremely rare. We report absence of the right SVC and congenital aortic annular hypoplasia with bicuspid aortic valve stenosis in a patient with Turner's syndrome. Aortic root extension with prosthetic valve replacement was performed and absent right SVC, which was detected incidentally during operation, is confirmed by postoperative venous angiogram.
Absence of the Mecc Gene in Methicillin-Resistant Staphylococcus Aureus Isolated From Various Clinical Samples: the First Multi-Centered Study in Turkey
(Elsevier Science London, 2019) Cikman, Aytekin; Aydin, Merve; Gulhan, Baris; Karakecili, Faruk; Kurtoglu, Muhammet G.; Yuksekkaya, Serife; Ozekinci, Tuncer
Background: mecA is a predefined gene causing methicillin resistance in Staphylococcus aureus (S. aureus) isolates; however, it has been shown that some methicillin-resistant S. aureus (MRSA) strains do not carry this gene. Recently, in isolates found to be MRSA-positive but mecA-negative, a new resistance gene called mecC, which is a homolog of mecA, has been reported. This study aimed to investigate the mecC and mecA genes in MRSA strains isolated from different geographic regions in Turkey. Methods: The sample of the study consisted of 494 MRSA strains isolated from seven geographical regions in Turkey between 2013 and 2016. The strains were obtained from 17 centers, comprising 13 university hospitals, three education and research hospitals, and one state hospital. Methicillin resistance in S. aureus strains was determined using the agar disk diffusion method with a cefoxitin disk and the agar dilution method with oxacillin. The mecC and mecA genes in MRSA strains was investigated by Polymerase Chain Reaction (PCR). Results: Of the MRSA strains investigated, 47.9% were isolated from intensive care units. Concerning sample type, 36.7% were detected in the respiratory tract (tracheal aspirate, sputum, etc.), 24.8% in blood, 18.7% in skin and soft tissues, 9.3% in nasal swabs, 5.4% in urine, 4.1% in ears, and 1% in sterile body fluid. Using PCR, mecC was not identified in any of the S. aureus strains isolated from different clinical microbiology laboratories. mecA gene positivity was found in 315 of the MRSA strains (63.8%). Staphylococcal Cassette Chromosome mec ( SCCmec) type was identified in 232 strains (46.9%), of which 136 (58.7%) were type II, 75 (32.4%) were type IV, 12 (5.1%) were type Mb, six (2.5%) were type I, and three (1.3%) were type III. Conclusion: This is the first multi-centered study to investigate MRSA strains isolated from different regions in Turkey. The mecC gene was not detected in any of the MRSA strains. We believe that this study will constitute an important basis for monitoring possible future changes. (C) 2019 The Authors. Published by Elsevier Limited on behalf of King Saud Bin Abdulaziz University for Health Sciences.
Absorption Ratio of Treatment Couch and Effect on Surface and Build-Up Region Doses
(Elsevier Science Bv, 2018) Tugrul, Taylan
Aim: In this study, at different fields, energies and gantry angles, treatment couch and rails dose absorption ratio and treatment couch effect on surface and build-up region doses were examined. Background: It is assumed that radiation attenuation is minimal because the carbon fiber couches have low density and it is not generally accounted for during treatment planning. Consequently, it leads to a major dosimetric mistake. Materials and methods: Solid water phantom was used for relative dose measurement. The measurements were done using a Farmer ion chamber with 0.6 cc volume and a parallel plane ion chamber starting from surface with 1 mm depth intervals at 10 x 10 cm(2) field, SSD 100 cm. Measurements were taken for situations where the beams intersect the couch and couch rails. Results: Dose absorption ratio of carbon fiber couch obtained at gantry angle of 180 was 1.52%, 0.69%, 0.33% and 0.25% at different field sizes for 6 MV. For 15 MV, this ratio was 0.95%, 0.27%, 0.20% and 0.05%. The absorption ratio is between 3.4% and 1.22% when the beams intersect with couch rails. The couch effect increased surface dose from 14% to 70% for 6 MV and from 11.34% to 53.03% for 15 MV. Conclusions: The results showed that the carbon fiber couch increased surface dose during posterior irradiation. Therefore, the skin -sparing effect of the high energy beams was decreased. If the effect of couch is not considered, it may cause significant differences at dose which reaches the patient and may cause tissue problems such as erythema. (C) 2017 Greater Poland Cancer Centre. Published by Elsevier Sp. z o.o. All rights reserved.
Accelerated Atherosclerosis in Haemodialysis Patients; Correlation of Endothelial Function With Oxidative Dna Damage
(Oxford Univ Press, 2012) Kaya, Yuksel; Ari, Elif; Demir, Halit; Soylemez, Nihat; Cebi, Aysegul; Alp, Hakan; Beytur, Ali
Background. Accelerated atherosclerosis is the major cause of mortality in patients on chronic haemodialysis (HD). The aim of this study was to evaluate the relationship between oxidative DNA damage [8-hydroxy-2'-deoxyguanosine/deoxyguanosine ratio (8-OHdG/dG ratio)], oxidative stress biomarkers and endothelial function in HD patients as an indicator of atherosclerosis. Methods. Forty-four chronic HD patients without known atherosclerotic disease and 55 age- and sex-matched healthy individuals were included in the study. Plasma malondialdehyde (MDA) levels and 8-OHdG/dG ratio were determined as oxidative stress markers. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured as antioxidants. Endothelial function was assessed by ultrasonography. Results. 8-OHdG/dG ratio and MDA levels were higher in HD patients than controls while SOD and GPx activities were lower in HD patients compared to controls. Flow-mediated dilatation FMD% in HD patients were lower than the control group (7.28 +/- 0.79 versus 11.18 +/- 0.82, P < 0.001). There was a significant negative correlation between FMD% and 8-OHdG/dG ratio (r = -0.678, P < 0.01) and MDA levels (r = 0.517, P < 0.01), while there was a significant positive correlation between FMD% and SOD (r = 0.538, P < 0.01) and GPx levels (r = 0.720, P < 0.01). Conclusions. Our data have demonstrated that HD patients exhibit increased oxidative DNA damage and decreased antioxidant activity. We propose that endothelial function is negatively correlated with 8-OHdG/dG ratio and positively correlated with antioxidant enzymes. To our knowledge, this is the first study to demonstrate the inverse relationship between endothelial function and plasma oxidative DNA damage in HD patients.
Accurately Localizing the Thyroid Tissue in Mature Cystic Teratoma of Ovary by Single-Photon Emission Computerized Tomography/Computerized Tomography
(Wolters Kluwer Medknow Publications, 2015) Demir, Yusuf; Ucler, Rifki; Alkis, Ismet; Bulut, Gulay
A 30-year-old woman with hyperthyroidism was admitted to hospital. Although increased thyroid function was found, the gland was normal in ultrasonography (USG). Additionally, thyroid iodine uptake and Tc-99m pertechnetate scintigraphy was normal. Abdomen USG detected a cystic pelvic mass in left ovary. A whole-body scan was performed 48 hours after oral ingestion of 29.6 MBq (0.8 mCi) 1-131 (iodine-131) revealed a round structure located to the left lower abdomen. Iodine uptake was detected in this cyst which was compatible with functional thyroid tissue demonstrated by SPECT/CT. The patient was underwent surgical operation and histopathology confirmed mature cystic teratoma. Accurate localization and depiction of thyroid tissue in ovary mass was provided with SPECT/CT.
Acetabular Fractures From Judet and Letournel To the Present: Research Trends and Global Outcomes With Bibliometric Analysis During 1980 To 2022
(Lippincott Williams & Wilkins, 2023) Dundar, Abdulrahim; Ipek, Deniz; Kaya, Sehmuz
Fractures of the acetabulum are one of the most challenging injuries treated by orthopedic surgeons. However, a bibliometric analysis has not been performed in the literature on acetabular fractures, which seriously affect the quality of life of patients. The aim of this study was to summarize the bibliometric and intellectual structure, and determine and map the most recent trends on the topic of acetabular fractures by analyzing the social and structural relationships between the different research components of articles published on the acetabular fractures. 1599 articles on acetabular fractures published between 1980 and 2022 were extracted from the Web of Science (WoS) database and analyzed. Bibliometric visualization maps were used to reveal trending topics, citation analyses, and international collaborations. Spearman correlation analysis was performed for correlation investigations. The trend in the expected number of articles to be published over the next few years was displayed using the exponential smoothing estimator. The top 3 contributing countries to the literature were United States of America (USA) (551, 34.4%), China (170, 10.6%), and Germany (160, 10%). The most active author was Berton R. Moed (n = 29) and the most active institution was the University of California System (n = 41). A high-level statistically significant correlation was found between the number of articles on the topic of acetabular fractures published by nations and the gross domestic product (GDP) and GDP per capita values of those countries (R = 0.719, P < .001; R = 0.701, P < .001, respectively). The trending topics researched in recent years were 3D printing, 3-dimensional printing, outcomes, Open Reduction and Internal Fixation (ORIF), mortality, Kocher-Langenbeck, Pararectus approach, tranexamic acid, transfusion, epidemiology, fracture mapping, modified Stoppa approach, post-traumatic osteoarthritis, pelvis fracture, pelvic trauma, fracture reduction, and pelvic ring injury. The leading countries in research on the subject of acetabular fractures were seen to be western countries with large economies (especially the USA, European countries, and Canada) and China, India and Turkey.
Acoustic Radiation Force Impulse (Arfi) Elastography Quantification of Muscle Stiffness Over a Course of Gradual Isometric Contractions: a Preliminary Study
(Soc Romana Ultrasonografe Medicina Biologie-srumb, 2015) Yavuz, Alpaslan; Bora, Aydin; Bulut, Mehmet Deniz; Batur, Abdussamet; Milanlioglu, Aysel; Goya, Cemil; Andic, Cagatay
Aims: To evaluate the feasibility of quantitative analysis of muscle stiffness by Acoustic Radiation Forced Impulse (ARFI) elastography over a course of graduate isometric voluntary contractions. Material and methods: The stiffness of the bilateral biceps muscle of 13 healthy volunteers was measured in real time by ARFI elastography, while the forearm was in neutral-extended position, 90 degree self-flexed positions and 90 degree self-flexed position, with altered weights ranging from 1 to 8 kg placed on flattened palmar surfaces consecutively. The determined increases in biceps muscle stiffness were measured for both arms and correlated with the loadings weights adopted at progressive trial stages. Results: The mean shear wave velocity (SWV) values of biceps muscles in a neutral position, in 90 degree flex position and 90 degree flex position with 1 to 8 kg weights on palmar surfaces were 2.162 +/- 0.302 m/sec, 3.382 +/- 0.581 m/sec, and 3.897 +/- 0.585 to 5.562 +/- 0.587 m/sec, respectively. Significant correlations between the muscle SWV values and related palmar weights and between the SWV values of right and left sides at different trial stages were identified (r=0.951 and r=0.954, respectively). A mutual propagation path of deep regions to entire areas was described to account for the distribution of increase in stiffness with increases in palmar weights. The confidence of method regarding inter-observer difference was confirmed by the correlation analyses of the results (r=0.998). Conclusions: ARFI elastography is a feasible imaging modality for quantifying the stiffness of isometrically voluntarily contracting muscles.
Acoustic Radiation Force Impulse Elastosonography of Placenta in Maternal Red Blood Cell Alloimmunization: a Preliminary and Descriptive Study
(Soc Romana Ultrasonografe Medicina Biologie-srumb, 2017) Cetin, Orkun; Karaman, Erbil; Arslan, Harun; Akbudak, Ibrahim; Yildizhan, Recep; Kolusari, Ali
Aims: Maternal red blood cell alloimmunization is an important cause of fetal morbidity and mortality in the perinatal period, despite well-organized prophylaxis programs. The objective of the study was to evaluate placental elasticity by using Acoustic Radiation Force Impulse (ARFI) in Rhesus (Rh) alloimmunized pregnant women with hydropic and nonhydropic fetuses and to compare those with healthy pregnant women. Material and methods: This case-control and descriptive study comprised twenty-eight healthy pregnant women, 14 Rh alloimmunized pregnant women with nonhydropic fetuses, and 16 Rh alloimmunized pregnant women with hydropic fetuses in the third trimester of pregnancy. Placental elasticity measurements were performed by ARFI elastosonography at the day of delivery. The maternal characteristics and neonatal outcomes of the patients were also noted. Results: The highest mean placental ARFI scores were observed in Rh alloimmunized pregnant women with hydropic fetuses (1.13 m/s) (p= 0.001). Healthy controls and Rh alloimmunized pregnant women with nonhydropic fetuses had similar mean placenta ARFI scores (0.84 m/s, 0.88 m/s, respectively) (p< 0.05). Conclusions: Based on the present findings, the placenta becomes stiffer in Rh alloimmunized pregnancies complicated with hydrops fetalis. The increased placental ARFI scores may be a supplemental marker for adverse pregnancy outcomes, additional to Doppler evaluation of middle cerebral artery. This data should be confirmed with a large sample size and prospective studies by using serial measurements of ARFI elastosonography in maternal red blood cell alloimmunization.
Acrodermatitis Enteropathica in Three Siblings
(Medknow Publications & Media Pvt Ltd, 2013) Karadag, Ayse Serap; Bilgili, Serap Gunes; Calka, Omer
Active Shrinkage Protects Neurons Following Axonal Transection
(Cell Press, 2023) Aydin, Mehmet Sxerif; Bay, Sadik; Yigit, Esra Nur; Ozgul, Cemil; Oguz, Elif Kaval; Konuk, Elcin Yenidunya; Ozturk, Gurkan
Trauma, vascular events, or neurodegenerative processes can lead to axonal injury and eventual transec(axotomy). Neurons can survive axotomy, yet the underlying mechanisms are not fully understood. Excessive water entry into injured neurons poses a particular risk due to swelling and subsequent death. Using in vitro and in vivo neurotrauma model systems based on laser transection and surgical nerve cut, demonstrated that axotomy triggers actomyosin contraction coupled with calpain activity. As a consequence, neurons shrink acutely to force water out through aquaporin channels preventing swelling and bursting. Inhibiting shrinkage increased the probability of neuronal cell death by about 3-fold. These studies reveal a previously unrecognized cytoprotective response mechanism to neurotrauma and offer fresh perspective on pathophysiological processes in the nervous system.
Activity of Cdk4/6 Inhibitors and Parameters Affecting Survival in Elderly Patients in Age-Subgroups: Turkish Oncology Group (Tog) Retrospective Study
(Bmc, 2024) Kahraman, Seda; Hizal, Mutlu; Demirel, Burcin Cakan; Guven, Deniz Can; Gumusay, Ozge; Uluc, Basak Oyan; Sendur, Mehmet Ali Nahit
Highly selective inhibitors of cyclin-dependent kinase 4 and 6 (CDK4/6is) have emerged as a standart of care for first- and second-line therapies in combination with endocrine therapy (ET) for HR+/HER2- metastatic breast cancer (MBC) patients. It has been reported that combination therapy is more effective than ET alone and is safe in elderly patients as well as young patients. Nevertheless, elderly and very old patients with HR+/HER2-MBC treated with CDK4/6 inhibitor (CDK4/6i) combinations are relatively underrepresented in randomized controlled trials. To contribute to the literature, we investigated the real-world efficacy, factors associated with survival and the rates of adverse events (AEs) of the treatment with palbociclib or ribociclib plus ET in the HR+/HER2- MBC patient cohort over the age of 65 for age subgroups. In this retrospective study, 348 patients were divided into subgroups: 65-69 years old, 70-79 years old and 80 years and older. Median PFS (mPFS) for whole group was 18.3 (95% CI,14.3-22.3) months. There was no significant difference in mPFS between age groups (p = 0.75). The estimated median OS (mOS) was 39.5 (95% CI, 24.9-54.1) months and there was no significant difference between age groups (p = 0.15). There was a meaningfull numerical difference that did not reach statistical significance in patients who received CDK4/6i treatment as the first line for MBC. Grade 3-4 AEs were reported in 42.7% for the entire group, and neutropenia was the most common (37.3%). It can be concluded that combination therapy with palbociclib or ribociclib with an ET partner has similar efficacy and is safe among subgroups of older patients diagnosed with HR+/HER2-MBC.
The Acute Effects of Simulated Hypoxic Training at Different Altitudes on Oxidative Stress and Muscle Damage in Elite Long-Distance Runners
(Peerj inc, 2025) Sarikaya, Muecahit; Oge, Beyza; Embiyaoglu, Nuri Mert; Selcuk, Muzaffer; Cinar, Vedat; Oner, Salih; Batrakoulis, Alexios
Background Understanding the impact of altitude on muscle damage and oxidative stress is essential for optimizing training and recovery strategies for athletes exposed to high-altitude conditions. Therefore, this study aimed to investigate the effects of acute exercise at different altitudes on oxidative stress and muscle damage. Methods A total of twelve elite long-distance runners (mean age: 20.3 +/- 1.5 years) from different branches participated in the study. The exercise protocol was the Bruce submaximal treadmill exercise test, which was conducted under three simulated hypoxic conditions (at 1,700 m, 2,450 m, and 3,200 m) and one normoxic condition (sea level). All measurements took place at the same time of the day. After the exercise protocol, 5 ml venous blood samples were taken from the participants, while heart rate and oxygen saturation were monitored at the 3rd, 6th, 9th, and 12th minutes during the exercise. Results Significant altitude-dependent variations were observed in oxidative stress markers, with total oxidant status (TOS) (p = 0.017) and malondialdehyde (MDA) (p < 0.001) levels increasing at higher altitudes, while total antioxidant status (TAS) (p < 0.001) exhibited an elevation and oxidative stress index (OSI) (p < 0.001) demonstrated a decline as altitude increased. However, no significant difference was found in creatine kinase (CK, p = 0.059) levels. Additionally, there were significant differences in the oxygen saturation measurement taken at the 3rd (p < 0.001), 6th (p < 0.001), 9th (p < 0.001), and 12th (p < 0.001), minutes following the exercise session. There was no difference in the pulse measurement taken at the 3rd and 12th minutes, but a difference was observed at the 6th and 9th minutes post-exercise (p < 0.01). Conclusions In conclusion, the study determined that endurance exercises performed under simulated normobaric hypoxia at different altitudes increased TAS and reduced OSI in elite long-distance runners. The increase in TAS and the reduction in OSI were more pronounced at higher altitudes, particularly at 2,450 m and 3,200 m, compared to sea level. These findings highlight the need for altitude-specific training and recovery strategies to minimize oxidative stress and muscle damage in athletes.

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