Phytochemical study and biological evaluation of the stem of Derris ferruginea Bentham

The genus Derris Loureiro belongs to the tribe Milletiae of the Leguminosae. It includes about fifteen species widely found in the tropical areas of Africa and Asia [1]. These plants have been traditionally used over centuries as fish poisoning, insecticide and pesticide, particularly due to their large production of rotenone [2]. Biological activities of Derris species are various: cytotoxic, antibacterial, antifungal, and antioxidant [3,4,5]. Though major secondary metabolites found in the genus are known to be flavonoids, including prenylated flavanones, and isoflavonoids such as rotenoids, very few phytochemical informations were available on D. ferruginea [6]. Different crude extracts were obtained from the stem (2kg, Soxhlet apparatus). They were fractionated using successively MPLC, LC, FCPC® (Fast Centrifugal Partition Chromatography, Kromaton Angers), Sephadex LH-20® gel and finally purified on preparative HPLC. Chemical structures of the isolated compounds were elucidated using 1H and 13C NMR spectrum as well as Mass Spectrometry. Most of these compounds were identified as prenylated flavonoids (flavanones and isoflavonoids). Biological effects of these compounds will be reported here, particularly antimicrobial, antiparasitic activities and inhibition of the formation of AGEs (Advanced Glycation End Products involved in age- and diabetes-related chronic diseases)

Anatomical study and reanalysis of the nomenclature of the anterolateral complex of the knee focusing on the distal iliotibial band: identification and description of the condylar strap

Background: The capsulo-osseous layer, short lateral ligament, mid-third lateral capsular ligament, lateral capsular ligament and anterolateral ligament are terms that have been used interchangeably to describe what is probably the same structure. This has resulted in confusion regarding the anatomy and function of the anterolateral complex of the knee and its relation to the distal iliotibial band. Purpose: To characterize the macroscopic anatomy of the anterolateral complex of the knee, in particular the femoral condylar attachment of the distal iliotibial band (ITB). We identified a specific and consistent anatomical structure that was not accurately described previously, connects the deep surface of the ITB to the condylar area, and is distinct from the anterolateral ligament, the capsulo-osseous layer and the Kaplan fibers. Study Design: Descriptive laboratory study. Methods: Sixteen fresh-frozen human cadaveric knees were used to study the anterolateral complex of the knee. Standardized dissections were performed that included a qualitative and quantitative assessment of the anatomy through both anterior (n=5) and posterior (n=11) approaches. Results: The femoral condylar attachment of the distal ITB was not reliably identified by anterior dissection but was in all posterior dissections. A distinct anatomical structure, hereafter termed condylar strap (CS), was identified between the femur and the lateral gastrocnemius on one side and the deep surface of the ITB on the other, in all posteriorly dissected specimens. The structure had a mean thickness of 0.88 mm, and its femoral insertion was located between the distal Kaplan fibers and the epicondyle. The proximal femoral attachment of the structure had a mean width of 15.82 mm and the width of the distal insertion of the structure on the ITB was 13.27 mm. The mean length of the structure was 26.33 mm on its distal border and 21.88 mm on its proximal border. Qualitative evaluation of behavior in internal rotation revealed that this anatomical structure became tensioned and created a tenodesis effect on the ITB. Conclusions: There is a consistent structure that attaches to the deep ITB and the femoral epicondylar area. The orientation of fibers suggest that it may have a role in anterolateral knee stability. Clinical Relevance: This new anatomical description may help surgeons to optimize technical aspects of lateral extra-articular procedures in cases of anterolateral knee laxity

Constrained Statistical Modelling of Knee Flexion from Multi-Pose Magnetic Resonance Imaging

© 1982-2012 IEEE.Reconstruction of the anterior cruciate ligament (ACL) through arthroscopy is one of the most common procedures in orthopaedics. It requires accurate alignment and drilling of the tibial and femoral tunnels through which the ligament graft is attached. Although commercial computer-Assisted navigation systems exist to guide the placement of these tunnels, most of them are limited to a fixed pose without due consideration of dynamic factors involved in different knee flexion angles. This paper presents a new model for intraoperative guidance of arthroscopic ACL reconstruction with reduced error particularly in the ligament attachment area. The method uses 3D preoperative data at different flexion angles to build a subject-specific statistical model of knee pose. To circumvent the problem of limited training samples and ensure physically meaningful pose instantiation, homogeneous transformations between different poses and local-deformation finite element modelling are used to enlarge the training set. Subsequently, an anatomical geodesic flexion analysis is performed to extract the subject-specific flexion characteristics. The advantages of the method were also tested by detailed comparison to standard Principal Component Analysis (PCA), nonlinear PCA without training set enlargement, and other state-of-The-Art articulated joint modelling methods. The method yielded sub-millimetre accuracy, demonstrating its potential clinical value

Polyphenolic content and pharmacological potential of french BFA propolis extracts

Propolis, or bee glue, is a natural resinous hive product collected by honeybees from buds and exudates of various trees and plants. Mixed with beewax and salivary enzymes, it is employed to fill cracks and embalm dead invaders in the hive. Propolis has been used in folk medecine since ancien times due to its pharmacological potential associated with antioxidant, antifungal, antibacterial as well as antitumoral properties. A batch of various French propolis extracts, supplied by “Ballot-Flurin Apiculteurs” (BFA), a company located in the South-West of France and specialized in apitherapy products, was fractionated and analysed by HPLC/MS. Its qualitative chemical composition highlights the presence of polyphenols such as hydroxycinnamic acid derivatives and flavonoids. Total polyphenol content and antioxidant activities were evaluated on six BFA propolis extracts, using respectively Folin-Ciocalteu, DPPH and ORAC assays. Preliminary antifungal (Candida albicans) and antibacterial (Staphylococcus aureus) evaluations will also be given

Hydroxamate siderophores of Scedosporium apiospermum

Scedosporium apiospermum is an emerging pathogen colonizing the airways of patients with cystic fibrosis and causing severe infections in immunocompromised hosts. In order to improve our knowledge on the pathogenic mechanisms of this fungus, we investigated the production of siderophores. Cultivation on CAS medium and specific assays for different classes of siderophores suggested the secretion of hydroxamates. A maximal production was obtained by cultivation of the fungus at alkaline pH in an iron-restricted liquid culture medium. Siderophores were then extracted from the culture filtrate by liquid/liquid extraction, and separated by reverse phase high performance liquid chromatography. Two siderophores, dimerumic acid and N α-methyl coprogen B, were identified by electrospray ionization-mass spectrometry and MS–MS fragmentation. Finally, comparison of various strains suggested a higher production of N α-methyl coprogen B by clinical isolates of respiratory origin. Studies are initiated in order to determine the potential usefulness of these siderophores as diagnostic markers of scedosporiosis

Antileishmanial polyphenols from Garcinia vieillardii

Seven xanthones, the new vieillardiixanthones B and C (1) and (7), pancixanthones A (2), B (3), 1,6-dihydroxyxanthone (6), pyranojacareubin and 5,6-O-dimethyl-2-deprenylrheediaxanthone together with two benzophenones, clusiachromene (4) and 3-geranyl-2,4,6-trihydroxybenzophenone (5) were isolated from the stem bark of the neocaledonian Garcinia vieillardii. 2, 5 and 6 showed a significant antileishmanial activity against the promastigote forms of Leishmania mexicana and L. infantum and against the amastigote forms of L. infantum

Preparative Isolation, Fast Centrifugal Partition Chromatography Purification and Biological Activity of Cajaflavanone from Derris ferruginea Stems

Introduction The Derris genus is known to contain flavonoid derivatives, including prenylated flavanones and isoflavonoids such as rotenoids, which are generally associated with significant biological activity. Objective To develop an efficient preparative isolation procedure for bioactive cajaflavanone. Methodology Fast centrifugal partition chromatography (FCPC) was optimised to purify cajaflavanone from Derris ferruginea stems in a single step as compared to fractionation from the cyclohexane extract by successive conventional solid–liquid chromatography procedures. The purification yield, purity, time and solvent consumption per procedure are described. The anti-fungal, anti-bacterial, anti-leishmanial, anti-plasmodial, anti-oxidant activities and the inhibition of advanced glycation end-products (AGEs) by cajaflavanone accumulation are described. Results FCPC enabled cajaflavanone purification in a single separation step, yielding sufficient quantities to perform in vitro biological screening. Interestingly, cajaflavanone had an inhibitory effect on the formation of AGEs, without displaying any in vitro anti-oxidant activity. Conclusion A simple and efficient procedure, in comparison with other preparative methods, for bioactive cajaflavone purification has been developed using FCPC

Purification hemisynthesis of xanthatin derivates and in vitro evaluation of their activity towards farnesyltransferase (PFTase)

Originating from America and introduced a few centuries ago in Europe, Xanthium macrocarpum DC. (Asteraceae) also called „Lampourde à gros fruits“ is a species commonly growing on the edges of the Loire. Xanthanolides (sesquiterpene lactones) found in this plant exhibit interesting biological activities [1]. These activities are usually explained by their alkylating properties due to the presence of the α-methylene-γ-lactone function which is also related to the toxicity of several plants. As recent reports pointed out the potential of dimeric or monomeric sesquiterpene lactones as farnesyltransferase (PFTase) inhibitors, we decided to explore this activity knowing that PFTase is an interesting target to find new effective therapeutic agents for the treatment of cancer. So, the objective was to obtained atoxic hemisynthetic derivates from the natural xanthanolides: xanthatin and xanthinin. These compounds were first isolated in one step from the crude chloroformic extract of the leaves of X. macrocarpum using differents methods of chromatography: silica gel and a 5L pilot scale FCPC® (Fast Centrifungal Partition Chromatograph, Kromaton, Angers, France). We have shown that FCPC® is more efficient for purification: solvent consumption is lowered (divided by 2), with highest purity (5 fold increase on average), high loading capacity (2g of extract/L of organic solvent), and manipulation time reduction (few hours versus few days) [2]. Sixteen derivates were investigated as potent inhibitors of protein farnesyl transferase. These results showed that the α-methylene-γ-lactone function is not required to insure a PFTase inhibitory activity whereas the α-methyl-γ-lactone function is responsible for a non competitive-inhibition

Unusual chemical composition of a Mexican Propolis collected in Yucatan

Introduction: Propolis, or bee glue, is a natural resinous hive product collected by honeybees from buds and exudates of various trees and plants. Mixed with beewax and salivary enzymes, it is employed to fill cracks and embalm dead invaders in the hive. Several studies about mexican propolis have revealed chemical profiles where cinnamic and phenylpropanoic acid derivatives as well as flavonoids dominated, whereas these extracts exhibited cytotoxic and/or antifungal activities. Research methods: An ethanolic extract of a batch of mexican propolis, collected in the state of Quintana Roo, Mexico, was first analysed by High Performance Liquid Chromatography coupled with Diode Array Detector (HPLC/DAD) but no major components could be detected. Its antioxidant activity was evaluated by 1,1-diPhenyl-2-PicrylHydrazyl (DPPH) assay as well, and its antibacterial (against 21 Gram-positive and Gram-negative strains including Staphyloccocus aureus) and antifungal (against Candida albicans and Aspergillus fumigatus) properties were evaluated through microdilution assays. Then, this extract was fractionated by Flash chromatography. Three of the fractions, containing the major constituents, were analysed by Gas Chromatography coupled with Mass Spectrometry (GC/MS). Results and discussion: This Mexican propolis did not show any antioxidant neither antibacterial nor antifungal activity. The main constituents of this Mexican propolis were identified as triterpenes (amyrenone, amyrin and amyrin-3-acetate) and sterols (fucosterol and sistosterol). This unusual composition associated with a Mexican propolis would thus explain the lack of biological activities. Further investigations will be conducted in order to link this chemical composition with the propolis plant sources

Normal phase HPLC profiling of the acetylcholinesterase activity in apolar plant extracts

Among nineteen evaluated Clusiaceous species, one stem bark CH2Cl2 crude extract was selected based on a significant inhibition of acetylcholinesterase (AChE) using the micro-dilution Ellman\u27s method [1]. A normal phase HPLC profiling with micro-fractionation of this extract provided discrete fractions every 20 seconds. In order to obtain a comprehensive profiling of AChE activity all microfractions were tested [2] in dilution assay (Ellman) as well as by bioautography (the Fast Blue B salt method). Furthermore the potency of inhibition was evaluated both by keeping the genuine concentration within the extract and after normalisation to a standard concentration level. From the active fractions five pure compounds were isolated and identified. The different methods of sample preparation and biological evaluation associated with normal-phase micro-fractionation of plant extracts are critically discussed