Browsing by Subject "MECHANISMS"

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    TGF-βs and SMADs Activities at the Site of Failed Neural Tube in the Human Embryos
    (TURKISH NEUROSURGICAL SOC) Barutcuoglu, M; Umur, AS; Vatansever, HS; Umur, N; Ozbilgin, K; Sayhan, S; Selcuki, M
    AIM: Transforming growth factor beta (TGF-beta) and Smads control intracellular signaling pathways in neurulation. Although previously reported similar experimental animal studies, the aim of this human study is to investigate the expression of TGF-beta (1,2,3) and Smads (1,2,3,6,7) in aborted human fetuses with myeloschisis. MATERIAL and METHODS: Twelve human fetuses with neural tube defect were obtained. They were stained with antibodies against TGF-beta 1, TGF-beta 2,TGF-beta 3, Smad (1,2,3), Smad 6 and Smad 7 using the indirect immunohistochemical technique. RESULTS: We noted mild immune reactivity of TGF-beta 1 and TGF-beta 2 in the open neural plate, motor neurons and surrounding tissue. Strong immune reactivity of TGF-beta 3 was shown in only open neural plate and surrounding tissue. Immunoreactivity of all Smads noted negative except Smad7. CONCLUSION: These results suggested at the site where the neural tube failed to close, TGF-beta 1,2 and Smads 1,2,3,6 do not continue their activity and decrease with internal timing of embryonic development. Additionally ectodermal layers are considered by embryo asnot closed wound and TGF-beta 3 activity may be an effort to repair the failed closure.
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    Immunohistochemical analysis of Ki-67, p53 and Bcl-2 expression related to histological features in gastroesophageal reflux disease
    (AVES) Ayhan, S; Nalbant, OA; Isisag, A; Küçükmentin, NT; Temiz, P
    Background/aims: The endoscopic and histologic findings of gastroesophageal reflux disease are usually indistinct. The current study was designed to define accurately the histology in gastroesophageal reflux disease and to develop a hypothesis that reflux produces immunohistochemical changes. Methods: The study was based on the examination of endoscopic esophageal biopsy specimens obtained from 20 patients with evidence of reflux with 24-hour pH-meter monitoring and from 20 control subjects without clinical or endoscopic reflux. The pathogenesis of reflux esophagitis was discussed by comparing the histopathologic changes with determined Ki-67, p53 and Bcl-2 immunoreactivity. Results: In this study, the presence of esophagitis was determined endoscopically in only 55% of the patients with gastroesophageal reflux disease, while microscopic esophagitis was detected in 60% of them. No correlation was found between presence of endoscopic esophagitis and microscopic esophagitis in the patients with gastroesophageal reflux disease. There was a significant difference between control cases and the patients according to histological parameters, which included basal activity (p=0.006), height of papillae (p=0.006), intraepithelial neutrophils (p=0.000), intraepithelial eosinophils (p=0.006), congestion (p=0.001), and dilated intercellular spaces (p=0.006). Immunohistochemically, there was a significant difference in the expression of p53 and Ki-67 between the three study groups (patients with I without microscopic esophagitis, controls) (p<0.05). However, there was no difference in Bcl-2 between the patients with reflux and control cases. Conclusions: In this study, we considered that microscopic esophagitis does not always accompany reflux, and the lack of reliable diagnostic histologic criteria is still a serious problem for pathologists. Immunohistochemically, an increase in cell proliferative activity and p53 protein accumulation to repair oxidative DNA damage related to reflux were observed. However, the close Bcl-2 immunoreactivity in all groups that was indicated by a weak positivity suggests that the inhibition of apoptosis may not be involved in reflux esophagitis.
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    Investigation on the tribology of Zr ion implanted tool steel
    (ELSEVIER SCIENCE SA) Akbas, N; Oztarhan, A; Monteiro, OR; Brown, IG
    AISI D3 tool steel was ion implanted with zirconium and the improvement in surface tribological properties investigated. The Zr ion implantation was done using a metal vapor vacuum ire (Mevva) broad-beam ion source, with a mean ion energy of 130 keV and at doses of 3.6 x 10(16), 5 x 10(16) and 1 x 10(17) ions/cm(2). Wear, friction and hardness of the implanted samples were measured and compared to the performance of unimplanted steel. The wear resistance was increased by about a factor of two, the friction remained about the same or was possibly increased by a small amount and the near-surface hardness was improved by a factor of live or more by the ion implantation. We also investigated the effect on the Zr implantation profile of the multi-component energy distribution of the ion beam. (C) 2002 Elsevier Science B.V. All rights reserved.
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    Vitamin D receptor gene polymorphism in children with urinary tract infection
    (SPRINGER) Aslan, S; Akil, I; Aslan, G; Onay, H; Ozyurt, BC; Ozkinay, F
    It is known that small alterations leading to different vitamin D receptor (VDR) alleles affect resistance or susceptibility to infections. In this study, we examined VDR gene polymorphisms in urinary tract infections (UTI), which are common and an important cause of morbidity in children and subsequently of renal scar formation. We evaluated 92 patients diagnosed with UTI and 105 children without prior history of UTI as a control group. The VDR gene polymorphisms BsmI, FokI, ApaI, and TaqI were evaluated in patients and controls. BsmI polymorphism genotype distribution was similar between groups. There was a significant difference between groups for FokI (p = 0 < 001); for the ff genotype, the risk of UTI was significantly increased (p < 0.01) ,at 3.94 times higher (odds ratio = 3.94; 95% confidence interval 1.71-9.09). ApaI polymorphism was significantly increased in the control group (p < 0.01) and evaluated as a protective factor. Comparing the TaqI genotype between groups, there was no statistically significant difference, but in both Tt and tt genotypes, there was minimal increased risk of UTI. The results of this study suggest that VDR gene polymorphisms can be important for susceptibility to UTI and renal scar formation. Association between VDR polymorphisms and UTI is in accordance with the understanding of how vitamin D modulates the immune response against infections.
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    Determination of antifungal efficiency of some fungicides and secondary metabolites of Trichoderma species against Botrytis cinerea
    (TRIVENI ENTERPRISES) Savas, NG; Yildiz, M; Eltem, R; Ozkale, E
    Aim: The present study aimed to investigate the antifungal effects of fenhexamid, cyprodinil+fludioxanil, Bacillus subtilis QST 713, Trichoderma secondary metabolites (EGE-K-38 and EGE-K-71) on 6 isolates of necrotrophic fungi (Botrytis cinerea) under in-vitro conditions. Methodology: the effects of volatile compounds produced by Trichoderma in culture media against Botrytis cinerea isolates. For non-volatile and volatile metabolites, measurements for growth inhibition were made with the mixture of filter sterilized liquid medium of Trichoderma and potato dextrose agar. The fungicidal effects of these non-volatile metabolites and fungicides were first evaluated according to the effective concentration (EC50) data of growing mycelium inhibition of disease agents. Results: the lowest fungicidal activity was determined as fenhexamide, which seems to have the lowest EC50 value of 0.05 ug m l . Both-1 non-volatile metabolites and volatile metabolites of Trichoderma strains showed strong inhibition against B. cinerea isolates under experimental conditions. The highest growth inhibition percentage was determined with volatile metabolites of Trihoderma atroviride EGE-K-71 strain as 71.8%. Interpretation: secondary metabolites and volatile compounds of Trichoderma strains produced in both liquid culture and dual culture conditions The study suggest that filtrates that contain can be used as an effective fungal control agents against pre and postharvest contamination of grapes with Botrytis cinerea.
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    The protective effect of metformin against the noise-induced hearing loss
    (SPRINGER) Kesici, GG; Öcal, FCA; Gürgen, SG; Erdem, SR; Ögüs, E; Erbek, HS; Özlüoglu, LN
    ObjectiveTo test the protective effect of metformin against noise-induced hearing loss.Methods24 rats were included in the study. The first group was exposed to noise only, the second group took metformin, the third group was exposed to noise and took metformin, and the fourth group was neither exposed to noise nor took metformin as control group. After measurement of baseline DPOAE and ABR of rats, the metformin group and the metformin+noise group received 300mg/kg/day metformin via gavage for 10days. On the 11th day, group 1 and group 3 were exposured to white noise at 105dB SPL for 15h. After noise exposure, DPOAE and ABR measurements of all rats were repeated on days 1st, 7th, and 21st. At the end of the study, all animals were sacrificed and cochlear tissues were separated for immunohistochemical assessments.ResultsABR threshold values and DPAOE measurements of groups 1 and 3 were deteriorated on the 1st day after noise, while deterioration in group 1 continued on 7th and 21st days, but normalized on 7th day in group 3. After immune staining, a significant immunoreaction was observed in the noise group, while the reaction in the noise+metformin group was close to the control group.ConclusionMetformin has a protective effect on noise-induced hearing loss in rats. As a conclusion, it is determined that metformin protects from permanent threshold shift in rats. It can be considered a good alternative for protecting noise-induced hearing loss.
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    Histological investigations on thymus of male rats prenatally exposed to bisphenol A
    (PERGAMON-ELSEVIER SCIENCE LTD) Aydemir, I; Kum, S; Tuglu, MI
    Bisphenol A is called as a endocrine-distrupting chemical because of the its steroid-like activity and it used in the construction of plastic containing materials. It is indicated that bisphenol A can pass the human serum, urine, follicular fluid, placenta and umblical cord as a result of the use of substances containing this agent. In this study, we aimed to investigate the effects of bisphenol A on the development of the thymus, a primary lymphoid organ which plays an important role in the specific immunity. The adult pregnant female rats were administered orally with bisphenol A (for 21 days) and postnatal thymus samples were obtained on day 21, 45 and 90 and were performed for histochemical and immunohistochemical staining for CD3, CD4, CD8 and CD79a and TUNEL assay for the apoptotic cells. Evaluation of all groups, CD3, CD4, CD8 and CD79a stainings were decreased in the experimental groups compared with control group. The apoptotic cells were determined in the all groups on day 90 as a result of the thymus involution. It is noted that there was not any histological and morphological damages in the rats prenatally exposed the bisphenol A. The effect of the bisphenol A is unknown in the future, but there is no problem in the adult rats. (C) 2018 Elsevier Ltd. All rights reserved.
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    Ultrastructural Dynamics of Transendothelial Migration of Lymphocytes Through High Endothelial Venules (HEVs) of the Mucosa Associated Peyer's Patches
    (PERIODICUM BIOLOGORUM) Balcan, E; Karaçali, S
    Background and Purpose: Although the pivotal role of high endothelial venules (HEVs) in the migration of leukocytes from the blood into the secondary lymphoid parenchyma is well established, conflicting ideas concerning the cellular dynamics both of leukocytes and endothelial cells throughout the migratory processes have been present. Here we focused specifically on the cellular dynamics of HEVs from Peyer's patches in an ultrastructural perspective. Materials and Methods: In order to determine the microstructural organization of transendothelial migration we used conventional methods for transmission electron microscopy. Results: Our results indicate that both lymphocytes and endothelial cells are highly active in the processes of transmigration steps, and a series of morphological and cellular alterations can occur depending upon their activity. Various types of cellular protrusions provide a direct contact between luminal lymphocytes and the endothelial cells at the initial phases of the migration. The endothelial protrusions subsequently embrace the lymphocytes and guide them into lymphoid stroma during the transcellular migration. Meanwhile, different sizes of vesicles show different cellular localizations according to their roles. The vesicles which are clustered near the lateral borders and the stand alone ones found only in the abluminal surfaces of endothelial cells might be involved in the paracellular migration. Concurrently, the other types of vesicles were smaller and appeared in the lateral border of the endothelial cells. Differ from the clustered and abluminally localized vesicles, they were closely related with plasma membranes. Conclusions: These results indicated that not only adhesion molecules, but also cellular dynamics of leukocytes and endothelial cells regulate the leukocyte traffic into lymphoid stroma or vice versa.
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    Handling of allergen immunotherapy in the COVID-19 pandemic: An ARIA-EAACI statement
    (WILEY) Klimek, L; Jutel, M; Akdis, C; Bousquet, J; Akdis, M; Bachert, C; Agache, I; Ansotegui, I; Bedbrook, A; Bosnic-Anticevich, S; Canonica, GW; Chivato, T; Cruz, AA; Czarlewski, W; Del Giacco, S; Du, H; Fonseca, JA; Gao, YD; Haahtela, T; Hoffmann-Sommergruber, K; Ivancevich, JC; Khaltaev, N; Knol, EF; Kuna, P; Larenas-Linnemann, D; Melén, E; Mullol, J; Naclerio, R; Ohta, K; Okamoto, Y; O'Mahony, L; Onorato, GL; Papadopoulos, NG; Pawankar, R; Pfaar, O; Samolinski, B; Schwarze, J; Toppila-Salmi, S; Shamji, MH; Ventura, MT; Valiulis, A; Yorgancioglu, A; Matricardi, P; Zuberbier, T
    The current COVID-19 pandemic influences many aspects of personal and social interaction, including patient contacts with health care providers and the manner in which allergy care is provided and maintained. Allergen-specific immunotherapy (AIT) is one of the most important treatment options for IgE-mediated allergies and is based on inducing an appropriate immune response in the allergic patient. This manuscript outlines the EAACI recommendations regarding AIT during the COVID-19 pandemic and aims at supporting allergists and all physicians performing AIT in their current daily practice with clear recommendations on how to perform treatment during the pandemic and in SARS-CoV-2 infected patients.
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    Does sucralfate prevent apoptosis occurring in the ischemia/reperfusion-induced intestinal injury?
    (GEORG THIEME VERLAG KG) Sencan, A; Yilmaz, Ö; Özer, E; Günsar, C; Genç, K; Ulukus, Ç; Taneli, C; Mir, E
    Background/Purpose: We have shown in a previous study that sucralfate is beneficial in the prophylaxis and treatment of hypoxia/reoxygenation-induced intestinal injury. The aim of this study is to investigate whether sucralfate has any effect on the prevention of apoptosis in the ischemia/reperfusion (I/R)-induced intestinal injury. Methods: Rats were randomized into three groups. Group 1 and 2 were subjected to I/R. Group 1 (treatment group) received sucralfate while group 2 (treatment control group) did not. Group 3 served as a normal control group (sham group). The terminal ileum was harvested for histopathologic investigation by light microscopy. The presence of apoptotic enterocytes (DNA fragmentation in cell nuclei) was detected by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end-labeling (TUNEL) reaction. Results: In treatment control group, 3 of 7 rats had severe inflammation. None of the sucralfate-treated rats showed severe inflammation, 6 of them only showed mild inflammatory changes (p < 0.05). The apoptotic percentage was found to be 37.1 +/- 9.4 in the sucralfate-treated group (group 1), whereas it was 45.4 +/- 3.9 in the untreated group (group 2) (p < 0.05). The sham group had a completely normal intestinal architecture. Conclusions: The present study shows that 1) the experimental model of I/R-induced intestinal injury induces enterocyte apoptosis; 2) sucralfate decreases enterocyte apoptosis in the experimental model of I/R-induced intestinal injury which may play a key role in the pathophysiological events leading to failure of the intrinsic gut barrier defense mechanisms.
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    Neuroprotective effects of MK-801 against traumatic brain injury in immature rats
    (ELSEVIER IRELAND LTD) Sönmez, A; Sayin, O; Gürgen, SG; Çalisir, M
    Traumatic brain injury (TBI) is a major health problem in pediatric ages and also has major social, economic, and emotional outcomes, with diverse sequelae in many spheres of everyday life. We aimed to investigate the effect of MK-801, a competitive NMDA receptor antagonist, on hippocampal damage and behavioral deficits on 10-day-old rat pups subjected to contusion injury. The aims of the present study were to determine: (i) the short term effects of MK-801 on hippocampal BDNF, NGF and NMDA receptor immunoreactivity and neuron density in hippocampus (ii) long term effects of MK-801 on cognitive dysfunction following TBI in the immature rats. MK-801, was injected intraperitoneally at the doses of 1 mg/kg of body weight immediately after induction of traumatic injury. Hippocampal damage was examined by cresyl violet staining, BDNF, NGF and NMDAR receptor immunohistochemistry on P10 day and behavioral alterations were evaluated using elevated plus maze and novel object recognition tests two months after the trauma. Histopathological and immunohistochemical evaluations showed that treatment with a single dose of 1 mg/kg MK-801 (i.p.) significantly ameliorated the trauma induced hippocampal neuron loss and decreased BDNF, NGF and NMDAR expressions in CA1, CA3 and DG hippocampal brain regions. Additionally, treatment with MK-801 ameliorated anxiety and hippocampus dependent memory of animals subjected to trauma. These results show that acute treatment of MK-801 has a neuroprotective role against trauma induced hippocampal neuron loss and associated cognitive impairment in immature rats. (C) 2015 Elsevier Ireland Ltd. All rights reserved.
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    Selected transient receptor potential channel genes' expression in peripheral blood mononuclear cells of multiple sclerosis
    (SAGE PUBLICATIONS LTD) Çakir, M; Saçmaci, H; Sabah-Özcan, S
    Transient receptor potential channels have responsibilities in many cellular processes such as cytokine production, cell differentiation, and cytotoxicity by affecting intracellular cation levels or intracellular signal pathways. Multiple sclerosis is a chronic autoimmune central nervous system (CNS) disease caused by environmental and genetic factors. In this study, we aim to investigate TRPV1-TRPV4, TRPM2, TRPM4, TRPM7, TRPC6, and TRPA1 mRNA expression levels, which are associated with the inflammatory process, in the peripheral blood mononuclear cells (PBMCs) of relapsing-remitting multiple sclerosis (RRMS) patients. Thirty-five healthy controls and age-gender matched thirty patients with RRMS were involved in the study. TRPC6, TRPA1, TRPM2, TRPM4, TRPM7, TRPV1, TRPV2, TRPV3, and TRPV4 PBMCs mRNA expression levels were determined by qPCR. In the present study, the TRPC6, TRPM7, TRPV1, TRPV3, and TRPV4 mRNA expressions of RRMS patients in PBMCs decreased at a significant level compared to the healthy control group (p = .000, p = .000, p = .044, p = .000, p = .004, respectively). The decreased expression of TRPC6, TRPM7, TRPV1, TRPV3, and TRPV4 in PBMCs may be associated with the pathogenesis of MS. Further studies are required to understand the mechanism of the relation between these TRP channels and MS and other autoimmune diseases.
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    Daily allergic multimorbidity in rhinitis using mobile technology: A novel concept of the MASK study
    (WILEY) Bousquet, J; Devillier, P; Anto, JM; Bewick, M; Haahtela, T; Arnavielhe, S; Bedbrook, A; Murray, R; van Eerd, M; Fonseca, JA; Almeida, MM; Bom, AT; Menditto, E; Passalacqua, G; Stellato, C; Triggiani, M; Ventura, MT; Vezzani, G; Annesi-Maesano, I; Bourret, R; Bosse, I; Caimmi, D; Cartier, C; Demoly, P; Just, J; Portejoie, F; Siroux, V; Viart, F; Bergmann, KC; Keil, T; Klimek, L; Mösges, R; Pfaar, O; Shamai, S; Zuberbier, T; Mullol, J; Valero, A; Spranger, O; Tomazic, PV; Kowalski, ML; Kuna, P; Kupczyk, M; Raciborski, F; Samolinski, B; Toppila-Salmi, SK; Valovirta, E; Cruz, AA; Sarquis-Serpa, F; da Silva, J; Stelmach, R; Larenas-Linnemann, D; Gonzalez, MR; Cabañas, MTB; Kvedariene, V; Valiulis, A; Chavannes, NH; Fokkens, WJ; Ryan, D; Sheikh, A; Bachert, C; Hellings, PW; VandenPlas, O; Ballardini, N; Kull, I; Melén, E; Westman, M; Wickman, M; Bindslev-Jensen, C; Eller, E; Bosnic-Anticevich, S; O'Hehir, RE; Agache, I; Bieber, T; Casale, T; Gemicioglu, B; Ivancevich, JC; De Vries, G; Sorensen, M; Yorgancioglu, A; Laune, D
    BackgroundMultimorbidity in allergic airway diseases is well known, but no data exist about the daily dynamics of symptoms and their impact on work. To better understand this, we aimed to assess the presence and control of daily allergic multimorbidity (asthma, conjunctivitis, rhinitis) and its impact on work productivity using a mobile technology, the Allergy Diary. MethodsWe undertook a 1-year prospective observational study in which 4 210 users and 32585days were monitored in 19 countries. Five visual analogue scales (VAS) assessed the daily burden of the disease (i.e., global evaluation, nose, eyes, asthma and work). Visual analogue scale levels <20/100 were categorized as Low burden and VAS levels 50/100 as High burden. ResultsVisual analogue scales global measured levels assessing the global control of the allergic disease were significantly associated with allergic multimorbidity. Eight hypothesis-driven patterns were defined based on Low and High VAS levels. There were <0.2% days of Rhinitis Low and Asthma High or Conjunctivitis High patterns. There were 5.9% days with a Rhinitis HighAsthma Low pattern. There were 1.7% days with a Rhinitis HighAsthma HighConjunctivitis Lowpattern. A novel Rhinitis HighAsthma HighConjunctivitis High pattern was identified in 2.9% days and had the greatest impact on uncontrolled VAS global measured and impaired work productivity. Work productivity was significantly correlated with VAS global measured levels. ConclusionsIn a novel approach examining daily symptoms with mobile technology, we found considerable intra-individual variability of allergic multimorbidity including a previously unrecognized extreme pattern of uncontrolled multimorbidity.
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    Influence of Li dopants on thermoluminescence spectra of CaSO4 doped with Dy or Tm
    (ELSEVIER SCIENCE BV) Wang, Y; Can, N; Townsend, PD
    Thermoluminescence emission spectra are presented for lithium doped variants of CaSO4:Dy or CaSO4:Tm dosimetry material. All three dopants (Li, Dy and Tm) variously introduce different changes in both the glow peak temperatures and the luminescence efficiency. In every case the emission signals display the line emission characteristic of the rare earth ions. At temperatures below similar to 50 K the relative peak intensities differ for Dy and Tm doped samples, and there are small temperature shifts between the Dy:Li and Tm:Li co-doped materials. Above room temperature the rare earth ions do not show peak temperature movements when co-doped with lithium. However they do influence the peak temperature by similar to 5 degrees C when they are the sole dopant. Inclusion of lithium dramatically moves the high temperature glow peak from similar to 200 degrees C down to 120 degrees C. All these changes are consistent with a single defect model in which the trapping sites and luminescence occur within the complexes formed of the rare earth ion, an intrinsic sulphate defect and lithium. The evidence and rationale for such a model are presented. There is discussion which suggests that such defect complexes are the norm in thermoluminescence. (C) 2011 Elsevier B.V. All rights reserved.
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    Determination of histopathological effects and myoglobin, periostin gene-protein expression levels in Danio rerio muscle tissue after acaricide yoksorrun-5EC (hexythiazox) application
    (TAYLOR & FRANCIS LTD) Koca, YB; Koca, S; Öztel, Z; Balcan, E
    Although pesticides are essential agrochemicals to annihilate harmful organisms in agriculture, their uncontrolled use has become an important threat to environmental health. Exposure to pesticides can affect many biological systems including immune system, endocrine system, and nervous system. However, the potential side effects of pesticides to skeletal muscle system remain unclear. Present study has focused on the evaluation of this issue by using an acaricide, yoksorrun-5EC (hexythiazox), in an aquatic model organism, Danio rerio. The histological analyses revealed that increased concentrations of the acaricide cause degradation of skeletal muscle along with increased necrosis and atrophy in myocytes, intercellular edema, and increased infiltrations between perimysium sheaths of muscle fibers. The effects of acaricide on myoglobin and periostin, which are associated with oxygen transport and muscle regeneration, respectively, were investigated at the gene and protein levels. RT-PCR results suggested that high concentration yoksorrun-5EC (hexythiazox) can induce myoglobin and periostin genes. Similar results were also obtained in the protein levels of these genes by western blotting analysis. These results suggested that yoksorrun-5EC (hexythiazox)-dependent disruption of skeletal muscle architecture is closely associated with the expression levels of myoglobin and periostin genes in Danio rerio model.
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    Neuroprotective Effects of Hesperidin and Naringin in SK-N-AS Cell as an In Vitro Model for Alzheimer's Disease
    (ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD) Kusi, M; Becer, E; Vatansever, HS; Yücecan, S
    Objective: Hesperidin and naringin are flavonoids that are found in citrus fruits. Our aim was to create an in vitro model of Alzheimer's disease (AD) and to evaluate the neuroprotective effects of hesperidin and naringin in SK-N-AS and AD model cells. Methods: A beta(25-35) was used to create an AD model in SK-N-AS cells. The cytotoxicity of hesperidin and naringin was evaluated using MTT. beta-amyloid, tau and alpha-synuclein distributions were analyzed using indirect immunoperoxidase staining to investigate the neuroprotective effects of hesperidin and naringin. Results: The AD model was created by 1 mu M of A beta(25-35) for 48 hours after ThT staining. The intensity of beta-amyloid was reduced through both hesperidin and naringin treatment in AD model cells. Both flavonoids significantly decreased the intensity of alpha-synuclein in SK-N-AS and AD model cells. Conclusions: Hesperidin and naringin can be potentially used as neuroprotective agents. Naringin may be more effective than hesperidin in the accumulation of beta-amyloid and tau proteins.
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    Evaluation of Heterozygous Deletion of TP53 Gene in Pleural Fluid Samples: A Case Series of 11 Patients
    (DERMAN MEDICAL PUBL) Dirican, N; Bagci, Ö; Uz, E; Ozturk, Ö; Bircan, HA; Dirican, A
    We described heterozygous deletion of tumor protein 53 (TP53) gene in 11 patients including 2 patients with non- malignant diseases (pneumonia) and 9 patients with malignant diseases [including small cell lung cancer (n = 3), non-small cell lung carcinoma (n = 4), non-Hodgkin's lymphoma (n= 1), and gastric carcinoma (n= 1)]. Chromosomal aberrant status was analyzed by fluorescence in situ hybridization with centromere specific and 17p13.1 locus specific probes. In 3 of 9 cancer patients we did not find malignant pleural effusion with histological examination and/or closed pleural biopsy. Heterozygous deletion of TP53 gene was found to be significantly higher in patients with malignant disease when compared to the patients with benign pleural fluid. As a result, we suggest that heterozygous deletion of TP53 may have indicator value for malignancy; however further studies are warranted to confirm this suggestion in large patient cohorts.
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    Evaluation of the Effects of Mobile Phones on the Neural Tube Development of Chick Embryos
    (TURKISH NEUROSURGICAL SOC) Umur, AS; Yaldiz, C; Bursali, A; Umur, N; Kara, B; Barutcuoglu, M; Vatansever, S; Selcuki, D; Selcuki, M
    AIM: The objective of this study is to examine the effects of radiation of mobile phones on developing neural tissue of chick embryos. MATERIAL and METHODS: There were 4 study groups. All Groups were placed in equal distance, from the mobile phones. Serial sections were taken from each Group to study the neural tube segments. RESULTS: The TUNEL results were statistically significant (p<0.001) at 30 and 48 hours in the third Group. We found low Bcl-2 levels partly in Group 4 and increased activity in Group 3. Caspase-3 was negative in the 48 and 72 hours in the Control Group, had moderate activity in the third Group 3, weak activity in the 48 hour, and was negative in the 72 hour in other groups. Caspase-9 immunoreactivity was weak in Group 1,2 and 3 at 30 hours and was negative in Group 1 and 4 at 48 and 72 hours. Caspase-9 activity in the third Group was weak in all three stages. CONCLUSION: Electromagnetic radiation emitted by mobile phones caused developmental delay in chick embryos in early period. This finding suggests that the use of mobile phones by pregnant women may pose risks.
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    ABRASIVE WEAR BEHAVIOUR OF SiCp-REINFORCED 2011 Al-ALLOY COMPOSITES
    (INST ZA KOVINSKE MATERIALE I IN TEHNOLOGIE) Uzkut, M
    In this study, the abrasive wear behaviour of aluminium-alloy (Al-2011) SiC-particle-reinforced composites was investigated and compared with that of the matrix alloy. The experimental variables were the SiC-particle proportion, sliding distance and abrasive grit size. Al-2011 reinforced composites containing volume fractions (7, 14 and 21) % SiCp were fabricated with the vortex method. Sliding-wear tests were carried out using a pin-on-disc abrasive-test machine where a sample slides against a SiC abrasive of different grit sizes at a fixed speed, under the load of 4 N at room conditions. The results show that the wear resistance of the composites was significantly larger than that of the Al-2011 alloy; it increased with the increasing SiC-particle proportion and decreased with the increasing abrasive grit size.
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    Combination of AT-101/cisplatin overcomes chemoresistance by inducing apoptosis and modulating epigenetics in human ovarian cancer cells
    (SPRINGER) Karaca, B; Atmaca, H; Bozkurt, E; Kisim, A; Uzunoglu, S; Karabulut, B; Sezgin, C; Sanli, UA; Uslu, R
    We investigated the effects of AT-101/cisplatin combination treatment on the expression levels of apoptotic proteins and epigenetic events such as DNA methyltransferase (DNMT) and histone deacetylase (HDAC) enzyme activities in OVCAR-3 and MDAH-2774 ovarian cancer cells. XTT cell viability assay was used to evaluate cytotoxicity. For showing apoptosis, both DNA Fragmentation and caspase 3/7 activity measurements were performed. The expression levels of apoptotic proteins were assessed by human apoptosis antibody array. DNMT and HDAC activities were evaluated by ELISA assay and mRNA levels of DNMT1 and HDAC1 genes were quantified by qRT-PCR. Combination of AT-101/cisplatin resulted in strong synergistic cytotoxicity and apoptosis in human ovarian cancer cells. Combination treatment reduced some pivotal anti-apoptotic proteins such as Bcl-2, HIF-1A, cIAP-1, XIAP in OVCAR-3 cells, whereas p21, Bcl-2, cIAP-1, HSP27, Clusterin and XIAP in MDAH-2774 cells. Among the pro-apoptotic proteins, Bad, Bax, Fas, phospho-p53 (S46), Cleaved caspase-3, SMAC/Diablo, TNFR1 and Cytochrome c were induced in OVCAR-3 cells, whereas, Bax, TRAILR2, FADD, p27, phospho-p53 (S46), Cleaved caspase-3, Cytochrome c, SMAC/Diablo and TNFR1 were induced in MDAH-2774 cells. Combination treatment also inhibited both DNMT and HDAC activities and also mRNA levels in both ovarian cancer cells. AT-101 exhibits great potential in sensitization of human ovarian cancer cells to cisplatin treatment in vitro, suggesting that the combination of AT-101 with cisplatin may hold great promise for development as a novel chemotherapeutic approach to overcome platinum-resistance in human ovarian cancer.