Interaction of lignans with human sex hormone binding globulin (SHBG)

Lignans bind to sex hormone-binding globulin (SHBG). The lignan with the highest binding affinity is (±)-3,4-divanillyltetrahydrofuran. In a double Stobbe condensation - without use of protecting groups - a wide variety of lignans with different substitution pattern in the aromatic and aliphatic part of the molecule was synthesized. These lignans were tested in a SHBG-binding assay which allowed to deduce the following relationship between structure and activity: 1) (±)-diastereoisomers are more active than meso compounds 2.) the 4-hydroxy-3-methoxy (guajacyl) substitution pattern in the aromatic part is most effective 3.) the activity increases with the decline in polarity of the aliphatic part of the molecule

In vitro production and exudation of 20-hydroxymaytenin from Gymnosporia heterophylla (Eckl. and Zeyh.) Loes. cell culture

The metabolite 20-Hydroxymaytenin (20-HM) is a member of the quinone-methide pentacyclic triterpenoids (QMTs) group. This metabolite group is present only in Celastraceae plants, and it has shown various biological activities from antioxidant to anticancer properties. However, most QMTs metabolites including 20-HM cannot be synthesized in a laboratory. Therefore, we optimized a plant tissue culture protocol and examined the potential of Gymnosporia heterophylla (synonym. Maytenus heterophylla) to produce 20-HM in an in vitro experiment. For the first time, we reported the optimum callus induction medium with a high percentage success rate of 82% from the combination of 1 mg/L indole-3-butyric acid and 5 mg/L naphthalene acetic acid. Later, our cell suspension culture cultivated in the optimum medium provided approximately 0.35 mg/g fresh weight of 20-HM. This concentration is roughly 87.5 times higher than a concentration of 20-HM presenting in Elaeodendron croceum (Celastraceae) leaves. In addition, we also found that 20-HM presented in a cultivation medium, suggesting that G. heterophylla cells secreted 20-HM as an exudate in our experiment. Noticeably, 20-HM was missing when Penicillium cf. olsonii occurred in the medium. These findings hint at an antifungal property of 20-HM

Fusarium species and mycotoxin profiles on commercial maize hybrids in Germany

Abstract High year-to-year variability in the incidence of Fusarium spp. and mycotoxin contamination was observed in a two-year survey investigating the impact of maize ear rot in 84 field samples from Germany. Fusarium verticillioides, F. graminearum, and F. proliferatum were the predominant species infecting maize kernels in 2006, whereas in 2007 the most frequently isolated species were F. graminearum, F. cerealis and F. subglutinans. Fourteen Fusariumrelated mycotoxins were detected as contaminants of maize kernels analyzed by a multi-mycotoxin determination method. In 2006, a growth season characterized by high temperature and low rainfall during anthesis and early grain filling, 75% of the maize samples were contaminated with deoxynivalenol, 34% with fumonisins and 27% with zearalenone. In 2007, characterized by moderate temperatures and frequent rainfall during the entire growth season, none of the 40 maize samples had quantifiable levels of fumonisins while deoxynivalenol and zearalenone were detected in 90% and 93% of the fields, respectively. In addition, 3-acetyldeoxynivalenol, 15-acetyldeoxnivalenol, moniliformin, beauvericin, nivalenol and enniatin B were detected as common contaminants produced in both growing seasons. The results demonstrate a significant mycotoxin contamination associated with maize ear rots in Germany and indicate, with regard to anticipated climate change, that fumonisins-producing species already present in German maize production may become more important. Keywords Deoxynivalenol . Ear rot . F. verticillioides . F. graminearum . Fumonisin . Zearalenon

Urinary cholesterol in cancer screening

Cholesterol determinations in morning urine samples were taken in 235 selected patients with a positive test for microscopic hematuria. Values ranged from 0.2 to 76.0 mg (median 5.5) in 23 patients with urologic malignancies and from 0.1 to 33.4 mg (median 1.1) in 38 patients with various benign diseases of the kidney or urogenital tract. In the 28 patients with urinary tract infections and 146 subjects without evidence of disorders of the kidney and the urogenital system, urinary cholesterol excretion was usually normal (0.1 to 1.9 mg; median 0.35). Using 1.0 mg urinary cholesterol per morning urine as a cutoff point, sensitivity for urologic carcinomas is about 80 per cent with a comparable high specificity of 90 per cent. Therefore, subsequent measurements of urinary cholesterol in populations with microscopic hematuria could define two groups, one with high prevalence and one with low prevalence of urologic malignancies. The less complicated colorimetric instead of gas-liquid chromatographic determination of urinary cholesterol can be recommended as a screening test for urologic carcinomas in populations with microscopic hematuria

Charakterisierung von N-Acyl-glutaminkonjugaten aus dem Regurgitat von Lepidoptera Larven

Viele Pflanzen reagieren bei Herbivorenbefall, z. B. durch Lepidoptera-Larven, mit Abwehrreaktionen, unter anderem mit der Produktion von Duftstoffen. Da einfache mechanische Verwundung diese Verteidigungseaktion nicht einleitet, scheinen im Regurgitat (Vorderdarminhalt) befindliche chemische Komponenten Auslöser (Elicitoren) der pflanzlichen Abwehr zu sein. Bei der Charakterisierung der chemischen Zusammensetzung von Regurgitat wurden schwerpunktsmässig N-Acylglutaminkonjugate, die als Elicitoren angesehen werden, untersucht: die Stereochemie der 17-Hydroxygruppe von Volicitin [(17S)-N-(17-Hydroxylinolenoyl)-L-glutamin) wurde bestimmt und neue N-Acylglutaminkonjugate wie N-(15,16-Epoxylinoleoyl)-glutamin, N-(15,16-Dihydroxylinoleoyl)-glutamin und N-(17-Phosphonoxylinolenoyl)-glutamin sowie N-(17-Acyloxyacyl)-glutamine wurden mit Hilfe von LC-MS/MS, GC-MS und synthetisierten Referenzverbindungen identifiziert. Die Biosynthese von N-Acylglutaminkonjugaten wird in vitro von Darmbakterien der Lepidoptera-Larven katalysiert. Die Tensideigenschaften von N-Acylglutaminen sind vermutlich Ursache für ihre Elicitorwirkung auf manche Pflanzen. Das zur Beschreibung der Interaktionen von Pflanze, Herbivor und Predator verwendete tritrophische System muss daher erweitert werden, um auch die mikrobielle Komponente zu berücksichtigen

Endophytes Are Hidden Producers of Maytansine in Putterlickia Roots

Several recent studies have lent evidence to the fact that certain so-called plant metabolites are actually biosynthesized by associated microorganisms. In this work, we show that the original source organism(s) responsible for the biosynthesis of the important anticancer and cytotoxic compound maytansine is the endophytic bacterial community harbored specifically within the roots of Putterlickia verrucosa and P. retrospinosa plants. Evaluation of the root endophytic community by chemical characterization of their fermentation products using HPLC-HRMSn, along with a selective microbiological assay using the maytansine-sensitive type strain Hamigera avellanea revealed the endophytic production of maytansine. This was further confirmed by the presence of AHBA synthase genes in the root endophytic communities. Finally, MALDI-imaging-HRMS was used to demonstrate that maytansine produced by the endophytes is typically accumulated mainly in the root cortex of both plants. Our study, thus, reveals that maytansine is actually a biosynthetic product of root-associated endophytic microorganisms. The knowledge gained from this study provides fundamental insights on the biosynthesis of so-called plant metabolites by endophytes residing in distinct ecological niches

Система поддержки принятие решений при проведении клинических исследований

Разработка программного обеспечения для проведения клинических исследований. Данное приложение может применяться для обеспечения целостности данных, безопасности субъекта исследования, качества продукта в ходе проведения исследования, что приведет к автоматизации рутинных процессов и будет способствовать повышению скорости и качества проводимых исследований.Development of software for conducting clinical trials. This application can be used to ensure data integrity, security of the research subject, and product quality during the research, which will lead to automation of routine processes and will help to improve the speed and quality of research