Atay, İrem | Kırmızıbekmez, Hasan | Yeşilada, Erdem | Gören, Ahmet Ceyhan

Other | 2015 | Turkish Journal of Chemistry39 ( 1 ) , pp.34 - 41

Abstract: A new nonglycosidic iridoid, sambulin B (1), was isolated from the methanol extract of Sambucus ebulus L. leaves along with a recently reported new nonglycosidic iridoid, 10-O-acetylpatrinoside aglycone (sambulin A) (2); 2 flavonoids, isorhamnetin-3-O-eta-D-glucopyranoside (3) and isorhamnetin-3-O-rutinoside (4); and a mixture of 2 flavonoids (5), quercetin-3-O-eta-D-glucopyranoside and quercetin-3-O-eta-D-galactopyranoside. Their structures were elucidated by 1-D and 2-D nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS) experiments.

Soğukpınar, İ. Cenk | Şahin, Duygu | Demirağ, Alp | Dinçel, Aylin Sepici | Kısakürek, Mustafa | Aakuş, M. Ali | Altan, Nilgün

Other | 2008 | Türk Biyokimya Dergisi33 ( 3 ) , pp.111 - 116

Amaç: Bu çalışmada hepatik iskemik önkoşullamanın intestinal iskemi-reperfüzyon hasarındaki lokal etkisinin yanı sıra, akciğer ve karaciğer gibi uzak doku hasarının incelenmesi amaçlandı. Gereç ve Yöntem: Deney hayvanları Wistar tipi albino ratlar 3 gruba ayrıldı. Grup 1, kontrol grubu olarak kabul edildi. Grup 2’de süperior mezenterik arter 1 saat klemplenerek iskemi oluşturuldu, klemp açıldıktan sonra 0, 2, 24, ve 48 saatlik reperfüzyonun ardından sakrifiye edilerek doku örnekleri alındı. Grup 3’ te hepatik pedikül 2 kez 5’er dakika klemplenip iskemi sağlandıktan sonra 10’ar dakika reperfüzyon yapılarak iskemik ön koşullanma yapıl . . .dı. Ardından süperior mezenterik arter 1 saat klemplenip iskemi sağlandı, klemp açıldıktan sonra 0., 2., 24. ve 48. saatlerde doku örnekleri alındı. Karaciğer, bağırsak, akciğer dokularında malondialdehit düzeyleri, akciğer ve bağırsak dokusunda miyeloperoksidaz aktivitesi incelendi. Bulgular: Araştırma sonucunda karaciğer dokusunda 2. ve 24. saatte, ince bağırsak dokusunda tüm saatlerde, akciğer dokusunda 2., 24. ve 48. saatlerde malondialdehit düzeyleri ve akciğer dokusunda tüm saatlerde MPO düzeyleri, Grup 2’de grup 3 e göre anlamlı şekilde yüksek bulundu. Grup 2, malondialdehit düzeyleri ince bağırsak ve akciğer dokusunda 2. saatte, karaciğer dokusunda 24. saatte en yüksek düzeye ulaştı ve daha sonra azalma eğilimi gösterdi, aynı şekilde akciğer dokusu MPO düzeyinin de 2. saatte en yüksek düzeyde olduğu gözlendi. İnce bağırsak MPO düzeylerinde ise her iki grupta da 48. saatte başlangıç değerlerine göre anlamlı azalma gözlendi. Sonuç: Hepatik iskemik önkoşullamanın intestinal iskemi-reperfüzyon hasarının lokal ve sistemik etkilerine karşı koruyucu etki gösterdiği düşünülmektedir. Aim: The aim of this study was to investigate the effects of hepatic ischemic preconditioning on the intestinal ischemia/reperfusion injury. Methods: Wistar albino rats were used in this experiment and randomly assigned into three groups: (i) Group I (sham); (ii) Group II: hepatic ischemia was formed by clamping on the superior mesenteric artery for 1 hour and reperfusion for 0, 2, 24, 48 hours and then subjects were sacrificed. (iii) Group III: preconditioning ischemia was obtained by clamping on hepatic pedicules twice for 5 min. and reperfused for 10 min. Then, the clamping and reperfusion processes used in Group II were repeated. Liver, intestine and lung malondialdehyde levels, lung and small intestine myeloperoxidase activities were evaluated. Results: Experimental data revealed significantly elevated levels of malondialdehyde in liver, intestine and lung tissues in Group II compared to Group III. In addition to these results, the myeloperoxidase activity of lung tissue was increased in Group II compared to Group III. In all tissues just like lung myeloperoxidase activity, malondialdehyde levels also reached to the highest level at reperfusion period of 2 h and then a tendency to decrease was observed. The decreased malondialdehyde levels were measured in Group II and Group III after 24 h. Conclusions: It can be suggested that the hepatic ischemic preconditioning may have protective effects against intestinal ischemia/reperfusion injury Daha fazlası Daha az

İnce, Ahmet T. | Snook, Richard D. | Dawson, John B.

Other | 2000 | Turkish Journal of Chemistry24 ( 1 ) , pp.43 - 58

A study of inherent noise sources present in a purpose built flame atomic magneto-optic rotation (AMOR) spectrometer system was carried out with a view to identifying their sources. Two different optical configurations were employed, a crossed polariser and a 45° offset polariser configuration. The offset polariser configuration was operated in both an AMOR and atomic absorption (AA) mode for the noise measurements. Two main interference frequencies were found to occur in all the optical measurement modes. An interference flame feature frequency (15.5 Hz -39.0 Hz) which arose from an "organ-pipe" effect in the gas flow . . . through the flame cooling sheets. The second interference frequency (at 100 Hz) was thought, to arise due to modulation of the analytes magneto-optic properties due to ripple on the electromagnet d.c. power supply. Photon noise and fluctuation noise were found to be present as background noise. The fluctuation noise was dominant at. higher analyte concentrations. The characteristics and origins of fluctuation noise are discussed and investigated for each measurement mode. The noise spectra of the conventional AA measurements were compared with those of the contemporary AMOR measurements, to ascertain any differences in noise power spectra which may affect, the signal-to-noise ratio Daha fazlası Daha az

İnce, T Ahmet

Other | 2001 | Turkish Journal of Chemistry25 ( 2 ) , pp.135 - 143

Analytical signals in an Atomic Magneto-Optic Rotation spectrometer are buried in noise at the limit of detection. The noisy analytical signals were analysed by carrying out mathematical correlation of their time domain waveforms. The noise components of signals were removed by auto-correlation to simplify the study. If noise interferes in analytical signals whose source is unclear, a cross-correlation of the output waveform with noise source may identify the source, e.g., mains frequencies and background radio signals. A cross-correlation will reveal whether the two signals are derived from the same source. This can also lead to an . . . improvement in the signal detection limit. Either of the two above situations can occur in studying analytical signals. In this study, both auto-and cross-correlation studies were carried out on analytical signals which had discrete noise sources present in their waveforms Daha fazlası Daha az