Development of Validated and Stability-Indicating LC-DAD and LC-MS/MS Methods for Determination of Avanafil in Pharmaceutical Preparations and Identification of a Novel Degradation Product by LCMS-IT-TOF

Avanafil (AVA), one of the most effective drugs prescribed for erectile dysfunction, is a pyrimidine-derivative PDE5 inhibitor. In the current work, new LC methods were developed and validated for quantitative determination of avanafil and qualitative determination of its degradation products. The quantitative determination of avanafil was carried out using liquid chromatography with photodiode array detection (LC-DAD) and liquid chromatography-tandem mass spectrometry LC-MS/MS methods, and fully validated according to the ICH Q2 (R1) guideline, while qualitative determination was performed using a liquid chromatography mass spectrometry-ion trap-time of flight (LCMS-IT-TOF) instrument. The separation of avanafil and its degradation products was carried out using the same reversed-phase chromatographic conditions, in which a second-generation C18-bonded monolithic silica column (Chromolith® High Resolution RP-18e, 100 × 4.6 mm, Merck KGaA) was used as stationary phase. Briefly, the methods enable quantitation of avanafil with high accuracy (recovery > 95%) and precision (RSD% < 2.0), within the ranges of 0.5–20 μg/mL for LC-DAD and 150–6000 ng/mL for LC-MS/MS. In the forced degradation studies, over and above currently existing data, a new oxidation-based degradation product, whose predicted m/z is 367.1168, was identified and its structure was confirmed by high-resolution mass spectrometric analysis. As the main advantage, either an LC-DAD or LC-MS/MS instrument can be chosen for interference-free quantitation of AVA, according to the facilities in quality-control laboratories

Doğal serin iklim buğdaygil yembitkilerinin bitki gelişme dönemlerine bağlı yem kalitesi değişimi ve çiftlik hayvanlarının günlük ihtiyacını karşılayabilme yetenekler

Aims: For a proper range management and livestock feeding operations need to detailed chemical analyses and knowledge on pasture composition. Methods and Results: Seven native cool-season grasses that are Festuca arundinaceae L., Brachypodium pinnatum (L.) Beauv., Phleum pretense L., Dactylis glomerata L., Bromus inermis Leyss., Lolium perenne L. and Hordeum bulbosum L. were evaluated for their nutritive value at five different phenological stages. The chemical composition, quality and therefore their feeding value so the animal performance are directly under control of the stage of plant phenology. Stage of plant maturity decreases dry matter digestibility, dry matter intake and protein content, but increases in lignocellulosic structure with the advance phenology of the whole investigated perennial species. Conclusions: The species which have thickand longer leaves, and higher leaf/stem ratio determined as the more digestible, and also the metabolizable energy of the fast growing ones was considerably higher. The vast majority of the minerals’ concentration was distinctly reduced at stem elongation to flowering and then increased remarkably from that point to developing seed stalks. The fast growing species accumulated the minerals more. Grass Tetany risk (K/(Ca+Mg)) of the investigated species increased remarkably at head emergence and flowering stage. Most of the species were detected within the boundaries of the recommended Ca/P ratio for diet. Significance and Impact of the Study: The native pastures seem to satisfy the daily maintenance requirements of most livestock in respect to most minerals without any supplementation via correct timing for feeding.Amaç: Doğru bir mera yönetimi ve hayvan besleme ilkeleri açısından mera kompozisyonu üzerinde detaylı kimyasal inceleme ve yoğun bir bilgiye ihtiyaç vardır. Yöntem ve Bulgular: Mevcut araştırmada; doğal çok yıllık serin mevsim buğdaygil türleri, Festuca arundinaceae L., Brachypodium pinnatum (L.) Beauv., Phleum pretense L., Dactylis glomerata L., Bromus inermis Leyss., Lolium perenne L. ve Hordeum bulbosum L. beş farklı bitki gelişim döneminde hayvan besleme kalitesi açısından değerlendirilmiştir. Bitki kimyasal kompozisyonu, kalite ve dolayısıyla besleme değerleri yani hayvan performansı bitki gelişim dönemlerinden doğrudan etkilenmektedir. İncelenen tüm türlerde kuru maddenin sindirilebilirliği, alımı ve protein içerikleri bitki olgunlaşması ile birlikte azaltırken, lignifikasyon artmıştır. Genel Yorum: İnce uzun yapraklı ve yaprak/sap oranı yüksek olan türlerin sindirilebilirlik oranlarının daha yüksek oldukları belirlenmiştir. Hızlı büyüyen türlerde ise metabolize olabilir enerji içeriğinin yüksekliği dikkate değer bulunmuştur Mineral elementlerin büyük çoğunluğunun konsantrasyonu sapa kalkma ve çiçeklenme dönemi arasında belirgin şekilde azalırken, bu dönemden başak/salkım çıkarma aşamasına kadar önemli bir artış saptanmıştır. Hızlı büyüyen türlerde mineral element birikimi de daha fazla gerçekleşmiştir. İncelenen türlerde çayır tetanisi riski (K/(Ca+Mg)) çiçeklenme aşamasında belirgin bir şekilde artış göstermiştir. Hesaplanan Ca/P oranının, tüm türler için rasyonda olması önerilen sınırlar içinde bulunduğu değerlendirilmiştir. Çalışmanın Önemi ve Etkisi: Araştırma bulguları incelenen doğal mera bitkilerinin, çoğu mineral element açısından çiftlik hayvanlarının günlük gereksinimlerini, herhangi bir ilaveye gerek olmaksızın karşılayabilecek kapasitede olduklarını ortaya koymuştur

Production of dihaploids in durum wheat using Imperata cylindrica L. mediated chromosome elimination

The possibility of obtaining dihaploid durum wheat ( Triticum durum L.) plants by interspecifc hybridization with Imperata cylindrica L. was studied. Ten local varieties and 1 commercial durum wheat variety (Triticum durum L., 2n = 4x = 28; AABB) were used as maternal lines. Imperata cylindrica L. (2n = 2x = 20) ecotypes sampled from diferent districts of Hatay were used as the pollen source. Isolated embryos were placed in an MS medium for plant regeneration 14 days afer the interspecifc hybridization. Te highest average seed setting, embryo formation, and dihaploid plant regeneration for the diferent hybrid combinations were determined as 31.1%, 15.5%, and 11.5%, respectively. Cytological observations revealed that all the regenerants had 2n = 2x = 14 chromosomes.The possibility of obtaining dihaploid durum wheat ( Triticum durum L.) plants by interspecifc hybridization with Imperata cylindrica L. was studied. Ten local varieties and 1 commercial durum wheat variety (Triticum durum L., 2n = 4x = 28; AABB) were used as maternal lines. Imperata cylindrica L. (2n = 2x = 20) ecotypes sampled from diferent districts of Hatay were used as the pollen source. Isolated embryos were placed in an MS medium for plant regeneration 14 days afer the interspecifc hybridization. Te highest average seed setting, embryo formation, and dihaploid plant regeneration for the diferent hybrid combinations were determined as 31.1%, 15.5%, and 11.5%, respectively. Cytological observations revealed that all the regenerants had 2n = 2x = 14 chromosomes

Effect to the young inflorescence length on the callus formation and plant regeneration in yellow bluestem (Bothriochloa ischaemmum (L.) Keng)

Bu çalışma, sarı sakalotu ( Bothriochloa ischaemum(L.) Keng) genç salkımlarının in vitrokültüründe salkım uzunluğunun kallus oluşumu ve bitki rejenerasyonuna etkisini saptamak amacıyla sürdürülmüştür. Arastırmada, in vitro kültüre iyi reaksiyon gösteren bir sarı sakalotu ekotipinin rejeneratlarından alınan farklı uzunluktaki salkımlar (2-25 mm) 8 mg/l dicamba içeren LS besi ortamında kültüre alınmışlardır. Araştırmada, kallus indüksiyon oranı salkım uzunluguna baglı olarak % 20.3 ile % 46.9 arasında degişmiştir. Salkım başına en yüksek kallus ağırlığı (111.5 mg/salkım) 11-15 mm uzunluğundaki salkımlardan elde edilmiştir. 15 mm'den daha uzun salkımların eksplantat olarak kullanılması durumunda salkım uzunlugu arttıkça salkım basına kallus ağırlığı azalma göstermiştir. En yüksek rejenerasyon oranı (10.860 bitkicik/salkım) 16-20 mm uzunlugundaki salkımlardan elde edilmiştir. 20 mm'den daha uzun salkımların eksplantat olarak kullanılması durumunda, rejenarasyon oranı azalmıştır. Araştırma sonuçları dikkate alınarak, 11-20 mm uzunluğundaki açık sarı renkli salkımların sarı sakalotunda embriyogenik kallus kültürlerinin elde edilmesi amacıyla eksplantat olarak kullanılabilecegi sonucuna varılmıştır.This study was carried out to determine the effect of inflorescence length on callus induction and plant regeneration in yellow bluestem ( Bothriochloa ischaemum(L) Keng). Inflorescences with different lengths (2-25 mm) from the in vitro regenerated plants of a Bothriochloa - ecotype with a good response to in vitro culture were cultured on LS-medium with addition 8 mg/l dicamba. The results of the study showed that the rates of callus induction related to inflorescence length varied from 20.3% to 46.9%. The highest callus weight per inflorescence was obtained from the inflorescences with a length of 11-15 mm. Increasing the inflorescence length decreased the callus weight per inflorescence when inflorescences longer than 15 mm were used as explant. The highest rate of regeneration (10.860 plantlets per inflorescence) was obtained from the inflorescence with a length of 16-20 mm. Increasing the inflorescence length decreased the regeneration rate when inflorescences longer than 20 mm were used as explant.It was concluded that inflorescences that are yellowish and 11-20 mm long can be used as explant for the establishment of the embryogenic callus cultures of Bothriochloa ischaemum

Effects of genotype and concentration of 2,4-d on callus induction and plant regeneration from young inflorescences of dallisgrass (Paspalum dilatatum poir)

This study was conducted to determine the effects of genotype and 2,4-D concentrations on the callus induction and plant regeneration from young inflorescences of dallisgrass ( Paspalum dilatatumPoir). Segments of young inflorescences from six different ecotypes of dallisgrass were cultured on MS-medium containing different con-centrations of 2,4-D ( 2, 4, 6, 8 and 10 mg/l). The results of the study showed that the ecotypes were significantly different in cal-lus induction ratio, callus weight per petri dish and plant regeneration from the young inflorescences. With respect to the ecotypes, callus induction ratio varied from 17.5 % to 65 %, callus weight from 75.25 to 365.1 mg/petri dish and number of regenerates per inflorescence segment from 0.775 to 1.612. The callus induction ratio, callus weight and regeneration ratio were also signifi-cantly influenced by the 2,4-D concentrations. The segments cultured on the MS medium containing 6 mg/l of 2,4-D gave the high-est values of callus induction ratio (74 %), callus weight (369.3 mg/petri dish) and regeneration ratio (2.094 regenerates perseg-ment).This study was conducted to determine the effects of genotype and 2,4-D concentrations on the callus induction and plant regeneration from young inflorescences of dallisgrass ( Paspalum dilatatumPoir). Segments of young inflorescences from six different ecotypes of dallisgrass were cultured on MS-medium containing different con-centrations of 2,4-D ( 2, 4, 6, 8 and 10 mg/l). The results of the study showed that the ecotypes were significantly different in cal-lus induction ratio, callus weight per petri dish and plant regeneration from the young inflorescences. With respect to the ecotypes, callus induction ratio varied from 17.5 % to 65 %, callus weight from 75.25 to 365.1 mg/petri dish and number of regenerates per inflorescence segment from 0.775 to 1.612. The callus induction ratio, callus weight and regeneration ratio were also signifi-cantly influenced by the 2,4-D concentrations. The segments cultured on the MS medium containing 6 mg/l of 2,4-D gave the high-est values of callus induction ratio (74 %), callus weight (369.3 mg/petri dish) and regeneration ratio (2.094 regenerates perseg-ment)

Quality by design approach with design of experiment for sample preparation techniques

The quality by design (QbD) based approach has begun to be embedded in various method development. Studies show that with the design of experiment tool, the analysis process has become more efficient, faster, and easier. The analysis has two components: Method development and sample preparation. Sample preparation can be at least as difficult as method development, and sometimes even more difficult. Therefore, in addition to the new techniques and materials developed in sample preparation, the QbD approach can significantly reduce the workload of the analysts and provide analysis with high accuracy and precision. So far, very limited studies have been come across in the literature about the QbD approach. The review in question has been prepared to encourage and guide researchers on this subject, and will greatly support this deficiency

Synthesis of Some Novel Thiadiazole Derivative Compounds and Screening Their Antidepressant-Like Activities

Novel thiadiazole derivatives were synthesized through the reaction of acetylated 2-aminothiadiazole and piperazine derivatives. The chemical structures of the compounds were clarified by Infrared Spectroscopy (IR), 1H Nuclear Magnetic Resonance Spectroscopy (1H-NMR), 13C Nuclear Magnetic Resonance Spectroscopy (13C-NMR) and Electronspray Ionisation Mass Spectroscopy (ESI-MS) spectroscopic methods. Antidepressant-like activities were evaluated by the tail-suspension (TST) and modified forced swimming (MFST) methods. Besides, possible influence of the test compounds on motor activities of the animals were examined by activity cage tests. In the TST, administration of the compounds 2c, 2d, 2e, 2f, 2g and 2h significantly decreased the immobility time of mice regarding the control values. Further, in the MFST, the same compounds reduced the total number of immobility behaviors while increasing swimming performance. However, no change was observed in the total number of climbing behaviors. These data suggested that compounds 2c, 2d, 2e, 2f, 2g and 2h possess notable antidepressant-like activities. Reference drug fluoxetine (10 mg/kg) was also exhibited its antidepressant activity, as expected. No significant difference was seen between the locomotor activity values of the test groups signifying that observed antidepressant-like activities are specific. Theoretical calculation of absorption, distribution, metabolism, excretion (ADME) properties for the obtained compounds were performed and obtained data supported the antidepressant-like potential of these novel thiadiazole derivatives

Open reduction technique for overlapping and locked pubic symphysis

A locked pubic symphysis can occur following a lateral compression injury of the pelvic ring when one pubic bone becomes entrapped behind the contralateral pubis or obturator foramen, In selecting the treatment modality, it is important to know the mechanism of injury. We presented the use of an open reduction technique in the treatment of a locked pubic symphysis in which open reduction external fixation application failed in the emergency department

Production of dihaploids in durum wheat using Imperata cylindrica L. mediated chromosome elimination

The possibility of obtaining dihaploid durum wheat ( Triticum durum L.) plants by interspecifc hybridization with Imperata cylindrica L. was studied. Ten local varieties and 1 commercial durum wheat variety (Triticum durum L., 2n = 4x = 28; AABB) were used as maternal lines. Imperata cylindrica L. (2n = 2x = 20) ecotypes sampled from diferent districts of Hatay were used as the pollen source. Isolated embryos were placed in an MS medium for plant regeneration 14 days afer the interspecifc hybridization. Te highest average seed setting, embryo formation, and dihaploid plant regeneration for the diferent hybrid combinations were determined as 31.1%, 15.5%, and 11.5%, respectively. Cytological observations revealed that all the regenerants had 2n = 2x = 14 chromosomes.The possibility of obtaining dihaploid durum wheat ( Triticum durum L.) plants by interspecifc hybridization with Imperata cylindrica L. was studied. Ten local varieties and 1 commercial durum wheat variety (Triticum durum L., 2n = 4x = 28; AABB) were used as maternal lines. Imperata cylindrica L. (2n = 2x = 20) ecotypes sampled from diferent districts of Hatay were used as the pollen source. Isolated embryos were placed in an MS medium for plant regeneration 14 days afer the interspecifc hybridization. Te highest average seed setting, embryo formation, and dihaploid plant regeneration for the diferent hybrid combinations were determined as 31.1%, 15.5%, and 11.5%, respectively. Cytological observations revealed that all the regenerants had 2n = 2x = 14 chromosomes