SCREEN ISOTROPIC LEAVES ON LIGHTLIKE HYPERSURFACES OF A LORENTZIAN MANIFOLD

Gulbahar, Mehmet Korean Mathematical Society 2017 대한수학회보 Vol.54 No.2

In the present paper, screen isotropic leaves on lightlike hypersurfaces of a Lorentzian manifold are introduced and studied which are inspired by the definition of isotropic immersions in the Riemannian context. Some examples of such leaves are mentioned. Furthermore, some relations involving curvature invariants are obtained.

Screen isotropic leaves on lightlike hypersurfaces of a Lorentzian manifold

Mehmet Gulbahar 대한수학회 2017 대한수학회보 Vol.54 No.2

In the present paper, screen isotropic leaves on lightlike hypersurfaces of a Lorentzian manifold are introduced and studied which are inspired by the definition of isotropic immersions in the Riemannian context. Some examples of such leaves are mentioned. Furthermore, some relations involving curvature invariants are obtained.

The expressions of HSP70 and αB-crystallin in myocarditis associated with foot-and-mouth disease virus in lambs

Mustafa Yavuz Gulbahar,Yonca Betil Kabak,Mehmet Onder Karayigit,Murat Yarim,Tolga Guvenc,Unal Parlak 대한수의학회 2011 JOURNAL OF VETERINARY SCIENCE Vol.12 No.1

This study describes the expression of heat shock protein70 (HSP70) and alpha-basic-crystallin (α-BC) and their association with apoptosis and some related adaptor proteins in the pathogenesis of foot-and-mouth disease virus (FMDV)-induced myocarditis in lambs. HSP70 was generally overexpressed in the myocardial tissues and inflammatory cells of FMDV-induced myocarditis with differential accumulation and localization in same hearts when compared to non-foot-and-mouth disease control hearts. α-BC immunolabeling showed coarse aggregations in the Z line of the cardiomyocytes in FMDV-infected hearts in contrast to control hearts. Overall, the results of this study show that the anti-apoptotic proteins, HSP70 and α-BC, were overexpressed with increased apoptosis in FMDV-infected heart tissues. Both proteins failed to protect the cardiomyocytes from apoptosis as defense mechanisms to the FMDV during the infection, suggesting that the virus is able to increase apoptosis via both downregulation and/or upregulation of these anti-apoptotic proteins.

Mammary fibroadenoma in a lamb

M. Yavuz Gulbahar,Tolga Guvenc,Murat Yarim,Yonca B. Kabak,Yuksel Sozgen 대한수의학회 2007 Journal of Veterinary Science Vol.8 No.4

A fibroadenoma was diagnosed in the left udder of a 3-month-old female Chios lamb. No recurrence was observed after surgery. Grossly, the tumor had a whitishgray lobular appearance, and the lobules were interlaced with thin septa. Microscopically, the tumor was composed of proliferating fibroepithelial tissue, including differentiated ducts lined by whorls and interlacing bundles of abundant loose fibrovascular stroma. Immunohistochemistry revealed the ductal epithelium to be positive for pancytokeratin (AE1/AE3) and loose fibrovascular stroma was positive for vimentin and basal cells covering the ductal epithelium of alpha-smooth-muscle actin. Immunostaining for the estrogen and progesterone receptors was negative. A diagnosis of mammary fibroadenoma was made based on the histological and immunohistochemical findings.

Alpha basic crystallin expression in canine mammary tumors

Tolga Guvenc,Mustafa Yavuz Gulbahar,Murat Yarim,Yonca Betil Kabak,Onder Karayigit,Mahmut Sozmen 대한수의학회 2012 JOURNAL OF VETERINARY SCIENCE Vol.13 No.1

The aim of this study was to evaluate prognostic and/or diagnostic factors of canine mammary tumors by immunohistochemically analyzing the expression of alpha basic crystallin (aB-c). For this, formalin-fixed, paraffin-embedded blocks of 51 naturally-occurring canine mammary tumors (11 benign and 40 malignant) were used. Tissue from eight normal canine mammary glands were served as a control. Immunohistochemically, in the control mammary tissues, a few luminal epithelial cells were aB-c positive but myoepithelial cells were negative. In benign or simple type malignant tumors, aB-c expression was observed in luminal epithelial cells while the myoepithelial basal cells were negative. In benign or complex type malign tumors, positive staining was predominantly found in the cytoplasm of epithelial cells. Immunoreactivity of aB-c was also observed in neoplastic myoepithelial cells. Statistically, the number of cells immunolabeled with aB-c was found to be significantly different among tissues from normal canine mammary glands, benign lesions, and malignant tumors (p < 0.05). aB-c immunoreactivity was higher in malignant tumors than the control mammary tissues (p < 0.001). Data obtained in the current study revealed a strong association between high expression levels af aB-c and primary mammary gland tumors in canines.

Applying nano-HA in addition to scaling and root planing increases clinical attachment gain

Uysal, Ozge,Ustaoglu, Gulbahar,Behcet, Mustafa,Albayrak, Onder,Tunali, Mustafa Korean Academy of Periodontology 2021 Journal of Periodontal & Implant Science Vol.51 No.-

Purpose: This study evaluated the efficacy of treating periodontitis using subgingival nano-hydroxyapatite powder with an air abrasion device (NHAPA) combined with scaling and root planing (SRP). Methods: A total of 28 patients with stage III periodontitis (grade B) were included in this study, although 1 was lost during follow-up and 3 used antibiotics. The patients were divided into a test group and a control group. All patients first received whole-mouth SRP using hand instruments, and a split-mouth approach was used for the second treatment. In the test group, the teeth were treated with NHAPA for 15 seconds at 70% power per pocket. Subgingival plaque samples were obtained from the 2 deepest pockets at the test and control sites before treatment (baseline) and 3 months after treatment. The full-mouth plaque index (PI), gingival index (GI), papillary bleeding index (PBI), bleeding on probing (BOP), probing depth (PD) and clinical attachment level (CAL) were recorded at baseline and at 1- and 3-month post-treatment. Real-time polymerase chain reaction was used to determine the colonisation of Treponema denticola (Td), Porphyromonas gingivalis (Pg), and Aggregatibacter actinomycetemcomitans in the subgingival plaque. Results: From baseline to the first month, the test group showed significantly larger changes in BOP and CAL (43.705%±27.495% and 1.160±0.747 mm, respectively) than the control group (36.311%±27.599% and 0.947±0.635 mm, respectively). Periodontal parameters had improved in both groups at 3 months. The reductions of PI, GI, BOP, PD, and CAL in the test group at 3 months were greater and statistically significant. The total bacterial count and Td and Pg species had decreased significantly by the third month in both groups (P<0.05). Conclusions: Applying NHAPA in addition to SRP improves clinical periodontal parameters more than SRP alone. Subgingival NHAPA may encourage clot adhesion to tooth surfaces by increasing surface wettability.

Effects of Tumor Necrosis Factor Alpha Blocker Adalimumab in Experimental Spinal Cord Injury

Borcek, Alp Ozgun,Civi, Soner,Ocal, Ozgur,Gulbahar, Ozlem The Korean Neurosurgical Society 2015 Journal of Korean neurosurgical society Vol.57 No.2

Objective : Tumor necrosis factor alpha (TNF-${\alpha}$) have proven effects in pathogenesis of neuroinflammation after spinal cord injury (SCI). Current study is designed to evaluate the effects of an anti-TNF-${\alpha}$ agent, adalimumab, on spinal cord clip compression injury in rats. Methods : Thirty two male adult Wistar rats were divided into four groups (sham, trauma, infliximab, and adalimumab groups) and SCI was introduced using an aneurysm clip. Animals in treatment groups received 5 mg/kg subcutaneous adalimumab and infliximab right after the trauma. Malondialdehyde (MDA) levels were studied in traumatized spinal cord tissues 72 hours after the injury as a marker of lipid peroxidation. Results : Animals that received anti-TNF-${\alpha}$ agents are found to have significantly decreased MDA levels. MDA levels were significantly different between the trauma and infliximab groups (p<0.01) and trauma and adalimumab groups (p=0.022). There was no significant difference in neurological evaluation of the rats using Tarlov scale. Conclusion : These results suggest that, like infliximab, adalimumab has favorable effects on lipid peroxidation induced by spinal cord trauma in rats.

Improvement of Pulmonary Functions Following Septoplasty: How Are Lower Airways Affected?

Arzu Tuzuner,Gulden Bilgin,Sule Demirci,Gulbahar Darilmaz Yuce,Cemile Acikgoz,Ethem Erdal Samim 대한이비인후과학회 2016 Clinical and Experimental Otorhinolaryngology Vol.9 No.1

Objectives. Nasal septal deviation is a frequent cause of increased nasal airway resistance. A narrow nasal airway would result in a decreased airflow into the lungs. The aim of the present study was to evaluate the alterations of the pulmonary functions following septoplasty using spirometry and 6 minutes walking test (6mWT). And reveal the correlation of symptom score improvement with nasal obstruction symptom score (NOSE) and sino-nasal outcome test (SNOT22) questionnaires following surgery. Methods. Thirty patients with obvious nasal septal deviations were enrolled in the study. All patients had a detailed otorhinolaryngologic examination, filled NOSE/SNOT22 questionnaires, performed spirometry and 6mWT preoperatively. One month after surgery, NOSE/SNOT22 questionnaires filled by subjects and spirometry with 6mWT were performed again, and the results were compared. Results. The mean total walking distance was 702.3±68.2 m preoperatively, and it improved to 753.2±72.6 m postoperatively (P<0.001). Total tour count increased from 11 (range, 10.8 to 12.0) to 12 (range, 11 to 13.3), and the difference was found statistically significant (P<0.001). When the preoperative and postoperative mean 6mWT results were compared, diastolic blood pressure increased from 70 to 80 mmHg (P=0.031), heart rate increased from 83.5±13.2 to 90.1±12.5 bpm (P=0.017), dyspnea rate decreased from 1 to 0 (P=0.002), and fatigue scores reduced from 2 to 1 (P=0.003). Evaluation on spirometry findings revealed that FIF50% (maximum inspiratory flow at 50% of forced vital capacity [FVC]) scores and peak expiratory flow (PEF) values improved significantly after surgery. Septoplasty improves the nasal breathing pattern. While reducing FEF50% (maximum expiratory flow at 50% of FVC)/FIF50%, it increases PEF and FIF50% values. In addition, as shown by 6mWT, exercise capacity improves following surgery. Postoperative NOSE and SNOT22 scores reduced markedly compared to preoperative values (P<0.001). Conclusion. These findings suggest that nasal septal surgery has a positive effect on pulmonary functions, and this can be an important clue for the relationship of lung disorders and nasal obstruction.

Syntheses of MgCO₃ and Na₂Mg(CO₃)₂ through solid-gas reactions mediated by alkali nitrates

Oh, Kyung-Ryul,Kim, Kang-Yeong,Kwak, Jin-Su,Atila, Gulbahar,Kwon, Young-Uk Elsevier 2018 Journal of solid state chemistry Vol.263 No.-

<P><B>Abstract</B></P> <P>In this work, we devised a set of molten salt-mediated reactions that can make use of gaseous reagents in forming solid products. In order for gaseous molecules to be reacted, its solubility in the molten salt medium needs to be high, which condition, in turn, requires the molten salt material to have a low melting point. We used alkali nitrate (ANO<SUB>3</SUB>, A = Li, Na, K, Rb, and Cs) as the reaction medium, for their low melting points, for the reactions of CO<SUB>2</SUB>(g) with various Mg-reagents. Reactions between 4MgCO<SUB>3</SUB>·Mg(OH)<SUB>2</SUB>·4H<SUB>2</SUB>O or Mg(OH)<SUB>2</SUB> with CO<SUB>2</SUB> in the presence of an ANO<SUB>3</SUB> above a certain quantity (30 wt% with respect to the MgO content in the Mg-reagent) produced single phase MgCO<SUB>3</SUB>, after washing the ANO<SUB>3</SUB> with water. On the contrary, the same reactions without ANO<SUB>3</SUB> did not show any sign of incorporating gaseous CO<SUB>2</SUB> in the final products. Similarly, the reaction of a mixture between Na<SUB>2</SUB>CO<SUB>3</SUB> and 4MgCO<SUB>3</SUB>·Mg(OH)<SUB>2</SUB>·4H<SUB>2</SUB>O or Mg(OH)<SUB>2</SUB> with CO<SUB>2</SUB> in an ANO<SUB>3</SUB> medium produced Na<SUB>2</SUB>Mg(CO<SUB>3</SUB>)<SUB>2</SUB>, a double carbonate of MgCO<SUB>3</SUB> with Na<SUB>2</SUB>CO<SUB>3</SUB>. The X-ray diffraction patterns and the thermogravimetry data under a CO<SUB>2</SUB> flow of MgCO<SUB>3</SUB> and Na<SUB>2</SUB>Mg(CO<SUB>3</SUB>)<SUB>2</SUB> indicate their high phase purity. The effects of various synthesis parameters such as the nature of ANO<SUB>3</SUB> and the amounts on the products were systematically investigated.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We performed solid-gas reactions in molten salt medium to provide solid products. </LI> <LI> We prepared anhydrous MgCO<SUB>3</SUB>, and Na<SUB>2</SUB>Mg(CO<SUB>3</SUB>)<SUB>2</SUB> in pure phase. </LI> <LI> Small amount of alkali nitrate can be used to prepare carbonate species. </LI> <LI> The kind of alkali nitrate affects the morphology of products. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Solid-gas reactions are performed through molten salt route to produce pure anhydrous MgCO<SUB>3</SUB> and Na<SUB>2</SUB>Mg(CO<SUB>3</SUB>)<SUB>2</SUB>.</P> <P>[DISPLAY OMISSION]</P>

Formation and crystal structure of a new double carbonate phase between Na and Cd

Kim, Kang-Yeong,Kwak, Jin-Su,Oh, Kyung-Ryul,Atila, Gulbahar,Kwon, Young-Uk Elsevier 2018 Journal of solid state chemistry Vol.267 No.-

<P><B>Abstract</B></P> <P>We report on the formation of a new phase Na<SUB>2</SUB>Cd(CO<SUB>3</SUB>)<SUB>2</SUB> (<B>1</B>) and its crystal structure. <B>1</B> belongs to the rare examples of double carbonates composed of d-block element metal elements. It is formed in a narrow window of temperature from 230 °C to slightly higher than 350 °C, because of which synthesis of <B>1</B> as a pure phase is practically impossible. We attempted to elucidate the crystal structure of <B>1</B> based on a powder X-ray diffraction pattern on a mixture between <B>1</B> and CdO as the major phase. Comparing with known structures of double carbonates of alkaline earth metal elements and introducing structural distortions to them, we identified the mother structure of <B>1</B> to be an orthorhombic variant of the Fairchildite structure reported for K<SUB>2</SUB>Ca(CO<SUB>3</SUB>)<SUB>2.</SUB> Rietveld refinements with a model in which the two symmetry-independent carbonate ions are disordered resulted in a good agreement with the observed data, which leads to the composition of <B>1</B> to be Na<SUB>2</SUB>Cd(CO<SUB>3</SUB>)<SUB>2</SUB>.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Solid-solid-gas reaction was performed to produce solid product. </LI> <LI> New double carbonate phase was formed between Na and Cd. </LI> <LI> Crystal structure of the product is determined to be a derivative of fairchildite structure. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>New double carbonate phase was observed between Na and Cd by solid-solid-gas reaction at 300 °C whose structure is analyzed as a fairchildite derivative.</P> <P>[DISPLAY OMISSION]</P>