A new elasmotheriine (Mammalia,Rhinocerotidae) from the Early Miocene of Spain

A new species of Hispanotherium from the Early Miocene of Spain is named. Its phylogenetic relationships within Elasmotheriina are discussed owing to a cladistic analysis. H. grimmi Heissig, 1974 and H. beonense Antoine, 1997 are consequently integrated in the genus Hispanotherium, together with the type species H. matritense and the new species, which differs from other ones by several dental and postcranial features. The westward dispersal of the Elasmotheriina from Asia toward Western Europe during the Early Miocene is hypothesized. To cite this article: P.-O. Antoine et al., C. R. Palevol 1 (2002) 19–26.     

Steroidal constituents from the leaves of Hosta longipes and their inhibitory effects on nitric oxide production

Hosta longipes (FR. et SAV.) MATSUMURA (Liliaceae) is an edible vegetable in Korea. This study was conducted with the aim of evaluating the potential of H. longipes as a functional food for the treatment of neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease. In this respect, the study resulted in the identification of three new steroidal compounds, longipenane (1), longipenane 26-O-β-d-glucopyranoside (2) and neogitogenin 3-O-α-l-rhamnopyranosyl-(1→2)-O-[β-d-glucopyranosyl-(1→4)]-β-d-galactopyranoside (3), along with two known steroidal saponins (4 and 5). The identification and structural elucidation of these compounds were based on 1D and 2D NMR measurements, high-resolution FAB mass spectroscopy (HR-FAB-MS), and chemical methods. A proinflammatory mediator, nitric oxide (NO), in murine microglial BV-2 cells was used to assess the anti-neuroinflammatory effect of the isolated compounds from H. longipes. Among them, compounds 4 and 5 showed strong inhibitory effects on NO production without high cell toxicity in lipopolysaccharide-activated BV-2 cells (IC₅₀ = 17.66 and 13.16 μM, respectively).     

The first camel from the Upper Miocene of Turkey and the dispersal of the camels into the Old World

Paracamelus cf. aguirrei from Çobanpinar (Turkey) is described. Rodents from that locality suggest a Late Turolian or Latest Miocene age, indicating that this is one of the oldest records of the genus. Paracamelus dispersed from North America in a relatively short period during the Late Turolian (MN13) into the extensive open and dry environments from central Asia to North Africa, as well as into southern Spain. To cite this article: J. van der Made et al., C. R. Palevol 1 (2002) 117–122.     

Chemical constituents from Tribulus terrestris and screening of their antioxidant activity

Two oligosaccharides (1, 2) and a stereoisomer of di-p-coumaroylquinic acid (3) were isolated from the aerial parts of Tribulus terrestris along with five known compounds (4–8). The structures of the compounds were established as O-β-d-fructofuranosyl-(2 → 6)-α-d-glucopyranosyl-(1 → 6)-β-d-fructofuranosyl-(2 → 6)-β-d-fructofuranosyl-(2 → 1)-α-d-glucopyranosyl-(6 → 2)-β-d-fructofuranoside (1), O-α-d-glucopyranosyl-(1 → 4)-α-d-glucopyranosyl-(1 → 4)-α-d-glucopyranosyl-(1 → 2)-β-d-fructofuranoside (2), 4,5-di-p-cis-coumaroylquinic acid (3) by different spectroscopic methods including 1D NMR (¹H, ¹³C and DEPT) and 2D NMR (COSY, TOCSY, HMQC and HMBC) experiments as well as ESI-MS analysis. This is the first report for the complete NMR spectral data of the known 4,5-di-p-trans-coumaroylquinic acid (4).The antioxidant activity represented as DPPH free radical scavenging activity was investigated revealing that the di-p-coumaroylquinic acid derivatives possess potent antioxidant activity so considered the major constituents contributing to the antioxidant effect of the plant.     

Lower Cretaceous plant cuticles and amber (Kirkwood Formation,South Africa)

Plant cuticle compressions and marble-like amber pieces have been extracted in one particular level from the Middle–Upper Valanginian of the Kirkwood Formation (Eastern Cape Province, South Africa). Preliminary cuticular study indicates high plant diversity and may complete previous data published from impressions only. Cretaceous amber is reported for the first time in Africa and corresponds to the oldest, southernmost record from Gondwanaland. To cite this article: B. Gomez et al., C. R. Palevol 1 (2002) 83–87.     

Chemical access to the mononuclear Mn(III) [(mL)Mn(OMe)]+ complex (mLH = N,N′-bis-(2-pyridylmethyl)-N-(2-hydroxybenzyl)-N′-methyl-ethane-1,2-diamine) and electrochemical oxidation to the Mn(IV) [(mL)Mn(OMe)]2+ species

Chemical oxidation in acetonitrile of the previously reported phenolato-bridged binuclear Mn(II) complex [(mL)MnMn(mL)]²⁺ (1), where mLH is pentadentate N,N′-bis-(2-pyridylmethyl)-N-(2-hydroxybenzyl)-N′-methyl-ethane-1,2-diamine ligand [C. Hureau, et al., Chem. Eur. J. 2004, 10, 1998–2010] using iodosylbenzene PhIO (dissolved in methanol) is described. The addition of one to four equivalents of PhIO per Mn ion leads to the transient formation of the mono-μ-oxo binuclear Mn₂(III,III) complex [(mL)Mn(μ-O)Mn(mL)]²⁺ (2), previously studied. After addition of five equivalents of PhIO per Mn ion, the mononuclear Mn(III) species [(mL)Mn(OMe)]⁺ (3) is quantitatively generated. The UV–Vis spectrum of 3 displays a broad band at 456 nm (ε = 1000 L mol⁻¹ cm⁻¹) attributed to phenolato to Mn(III) charge transfer transition. Complex 3 exhibits a reversible oxidation wave at E^1/2 = 0.68 V versus SCE, and the mononuclear Mn(IV) complex [(mL)Mn(OMe)]²⁺ (3^ox) can thus be generated by exhaustive electrolysis at 1.0 V versus SCE. The 9.4 GHz EPR spectrum of complex 3^ox shows a strong transition near g = 4 consistent with a rhombically distorted S = 3/2 system with a zero-field splitting dominating the Zeeman effect. UV–Vis spectrum displays a large phenolato to Mn(IV) charge transfer transition at 670 nm (ε = 2450 L mol⁻¹ cm⁻¹).     

Design,synthesis and biological evaluation of N,N-3-phenyl-3-benzylaminopropanamide derivatives as novel cholesteryl ester transfer protein inhibitor

A series of N,N-3-phenyl-3-benzylaminopropanamide derivatives were identified as novel CETP (cholesteryl ester transfer protein) inhibitors. In our previous study, lead compound L10 was discovered by pharmacophore-based virtual screening (Dong-Mei Zhao et al., 2014). Based on L10 (IC₅₀ 8.06 μM), compound HL6 (IC₅₀ 10.7 μM) was discovered following systematic structure variation and biological tests. Further optimization of the structure–activity relationship (SAR) resulted in N,N-3-phenyl-3-benzylaminopro panamides derivatives as novel CETP inhibitors. They were synthesized and evaluated against CETP by BODIPY-CE fluorescence assay. Among them, HL16 (IC₅₀ 0.69 μM) was a highly potent CETP inhibitor in vitro. In addition, HL16 exhibited favorable HDL-C enhancement and LDL-C reduction in vivo by hamster. The molecular docking of HL16 into the CETP was performed. The binding mode demonstrated that HL16 occupied the CETP binding site and formed interactions with the key amino acid residues.     

Cytotoxicity of a naturally occurring furoquinoline alkaloid and four acridone alkaloids towards multi-factorial drug-resistant cancer cells

IntroductionChemotherapy is one of the preferred mode of treatment of malignancies, but is complicated by the expression of diverse resistance mechanisms of cancer cells.MethodsIn the present study, we investigated the cytotoxicity of five alkaloids including a furoquinoline montrofoline (1) and four acridones namely 1-hydroxy-4-methoxy-10-methylacridone (2), norevoxanthine (3), evoxanthine (4), 1,3-dimethoxy-10-methylacridone (5) against 9 drug-sensitive and multidrug-resistant (MDR) cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of these compounds, whilst caspase-Glo assay was used to detect caspase activation. Cell cycle, mitochondrial membrane potential (MMP) and levels of reactive oxygen species (ROS) were all analyzed via flow cytometry.ResultsFuroquinoline 1 as well as the acridone alkaloids 2–5 displayed cytotoxic effects with IC₅₀ values below 138 µM on all the 9 tested cancer cell lines. The IC₅₀ values ranged from 41.56 µM (towards hepatocarinoma HepG2 cells) to 90.66 µM [towards colon carcinoma HCT116 (p53^−/−) cells] for 1, from 6.78 µM [towards HCT116 (p53^−/−) cells) to 106.47 µM [towards breast adenocarcinoma MDA-MB-231-pcDNA cells] for 2, from 5.72 µM (towards gliobastoma U87MG.ΔEGFR cells) to 137.62 µM (towards leukemia CCRF-CEM cells] for 3, from 6.11 µM [towards HCT116 (p53^+/+) cells] to 80.99 µM (towards HepG2 cells] for 4, from 3.38 µM (towards MDA-MB-231-BCRP cells) to 58.10 µM (towards leukemia CEM/ADR5000 cells] for 5 and from 0.20 µM (against CCRF-CEM cells) to 195.12 µM (against CEM/ADR5000 cells) for doxorubicin. Acridone alkaloid 5 induced apoptosis in CCRF-CEM leukemia cells, mediated by increased ROS production.ConclusionsThe five tested alkaloids and mostly acridone 5 are potential cytotoxic natural products that deserve more investigations to develop novel cytotoxic compounds against multifactorial drug-resistant cancers.     

Two new metabolites from Portulaca oleracea and their anti-inflammatory activities

Two new metabolites, identified as 6-phenylbenzofuran-4-ol, named olerabenzofuran (1), and 2-(furan-2-yl)− 6-hydroxy-1 H-inden-1-one, named oleraindenone (2), together with eight furan compounds obtained for the first time, (+)-pinoresinol (3), (-)-syringaresinol (4), (+)-diasyringaresinol (5), (+)-episyringaresinol (6), (2 S)− 1-[2-(furan-2-yl)− 2-oxoethyl]− 5-oxopyrrolidine-2-carboxylic acid (7), methyl (2 S)− 1[2-(furan-2-yl)− 2-oxoethyl]− 5-oxopyrrolidine-2-carboxylate (8), drynaran (9), and 2-furoic acid (10), were isolated from Portulaca oleracea L., and spectroscopic methods, including 1D and ²D NMR and UHPLC-ESI-QTOF/MS spectrometry techniques, were employed to determine their structures. It was suggested that both olerabenzofuran (1) and oleraindenone (2) could significantly inhibit inflammatory factor interleukin-1β (IL-1β) in RAW 264.7 cells induced by LPS.     

Proposition de reconstitution du deuxième crâne d’Homo erectus de Yunxian (Chine)

A proposal of reconstruction of the second Homo erectus skull from Yunxian (China). In 1989 and 1990, two Homo erectus crania were recovered from Yunxian (Hubei province) in archaeological levels dated to more than 780 000 years. Considered along with Lantian, these skulls represent the oldest human remains discovered in China to date, constituting important palaeontological finds. Nevertheless, the crania were badly deformed during the course of fossilization, necessitating extensive cranial reconstruction. Of the two crania, only Yunxian II was in sufficient condition to carry out this reconstruction. Using sophisticated techniques only recently applied in human palaeontology, including computed tomography and rapid prototyping, and incorporating taphonomic and morphometrically-based hypotheses, we were able to correct virtually the deformation and to produce a 3D prototype of Yunxian II. To cite this article: A. Vialet et al., C. R. Palevol 4 (2005).     

Versatile near-infrared fluorescent probe for in vivo detection of Aβ oligomers

Amyloid-β oligomers (AβOs) enrichment in brain is highly related to Alzheimer’s pathogenesis, but tracing them in the brain by imaging technique is still a great challenge due to their heterogeneity and metastability. Herein, a new near-infrared (NIR) fluorescent probe, namely, PTO-41, was designed and synthesized to specifically target AβOs. PTO-41 possesses excellent functional properties including optimal fluorescent properties (emission maxima at 680 nm upon interacting with AβOs), high affinity (K_d = 349 nM), low cell toxicity, desirable lipophilicity (log P = 2.24), and fast wash out from the brain (brain_{2 min}/brain_{60 min} = 5.0). Furthermore, PTO-41 exhibits a high sensitivity toward AβOs in vitro phantom imaging experiments. More importantly, PTO-41 shows great capacity to differentiate between 4-month-old APP/PS1 model mice from age-matched control mice using in vivo imaging. In summary, PTO-41 almost meets all the requirements as a versatile NIR fluorescent probe for the detection of AβOs both in vitro and in vivo.     

Evaluation of nitrogen excretion equations for ryegrass pasture-fed dairy cows

Accurate and precise estimates of nitrogen (N) excretion in faeces and urine of dairy cattle may provide direct tools to improve N management and thus, to mitigate environmental pollution from dairy production. Empirical equations of N excretion have been evaluated for indoor dairy cattle but there is no evaluation for cows fed high proportions of fresh forage. Therefore, the objective of the current study was to evaluate N excretion equations with a unique data set of zero-grazing experiments. Through literature searches, 89 predictive equations were identified from 13 studies. An independent data set was developed from seven zero-grazing experiments with, in total, 55 dairy Holstein-Friesian cows. Models’ performance was evaluated with statistics derived from a mixed-effect model and a simple regression analysis model. Squared sample correlation coefficients were used as indicators of precision and based on either the best linear unbiased predictions (R²_BLUP) or model-predicted estimates (R²_MDP) derived from the mixed model and simple regression analysis, respectively. The slope (β₀), the intercept (β₁) and the root mean square prediction error (RMSPE_m%) were calculated with the mixed-effect model and used to assess accuracy. The root mean square prediction error (RMSPE_sr%) and the decomposition of the mean square prediction error were calculated with the simple regression analysis and were used to estimate the error due to central tendency (mean bias), regression (systematic bias), and random variation. Concordance correlation coefficient (CCC) were also calculated with the simple regression analysis model and were used to simultaneously assess accuracy and precision. Considering both analysis models, results suggested that urinary N excretion (UN; R²_MDP = 0.76, R²_BLUP = 0.89, RMSPE_m% = 17.2, CCC = 0.82), total manure N excretion (ManN; R²_MDP = 0.83, R²_BLUP = 0.90, RMSPE_m% = 11.0, CCC = 0.84) and N apparently digested (NAD; R²_MDP = 0.97, R²_BLUP = 0.97, RMSPE_m% = 5.3, CCC = 0.95) were closely related to N intake. Milk N secretion was better predicted using milk yield as a single independent variable (MilkN; R²_MDP = 0.77, R²_BLUP = 0.97, RMSPE_m% = 6.0, CCC = 0.74). Additionally, DM intake was a good predictor of UN and ManN and dietary CP concentration of UN and ManN. Consequently, results suggest that several evaluated empirical equations can be used to make accurate and precise predictions concerning N excretion from dairy cows being fed on fresh forage.     

Anti-folate quintuple mutations in Plasmodium falciparum asymptomatic infections in Yaoundé, Cameroon

A major challenge in the fight to effectively control malaria is the emergence of resistant parasite to drugs used in therapy as well as for chemoprevention. In this study, single nucleotide polymorphisms (SNPs) associated with Plasmodium falciparum resistance to sulfadoxine-pyrimethamine (SP), one of the partner drugs in artemisinin-based therapies (ACTs) were studied in asymptomatic P. falciparum isolates from Cameroon. Dried Blood spots were collected from children with asymptomatic malaria enrolled during a household survey. The P. falciparum dihydrofolate reductase (Pfdhfr), dihydropteroate synthase (Pfdhps) and Kelch 13 genes were amplified and point mutations in these gene sequences were analyzed by sequencing. Among a total of 234 samples collected, 51 showed parasitaemia after microscopic examination of which 47 were P. falciparum mono-infections. Molecular analysis revealed 97.3% of mutant alleles at codons 51I, 59R and 108 N in Pfdhfr gene. In Pfdhps gene the most common mutation was 437G (83.3%); followed by 436A (47.6%) and 436F (28.6%). The association of mutations in the two genes (dhfr + dhps) showed 11 different haplotypes including three sextuple mutants (IRNI + AGKGA, IRNI + AAKGS, IRNI + AGKAS) and one septuple mutant (IRNI + AGKGS). For K13 gene no SNPs were seen in the studied asymptomatic malaria samples. The findings revealed presence of SP-resistant alleles in asymptomatic infected individuals with presence of sextuples and septuple SNPs. This emphasizes that regular profiling of antimalarial drugs resistance markers in such population is essential for malaria control and elimination programmes.     

Antibacterially active phenolic lipid derivatives from Comarum salesovianum (Steph.) Aschers. et Gr.

The antibacterial activity-guided purification of the dichloromethane fraction of the aerial parts of Comarum salesovianum (Steph.) Aschers.et Gr. led to the isolation and elucidation of three phenolic lipid derivatives: 6-(non-8-enyl) salicylic acid (1), 6-nonyl salicylic acid (2) and 3-(non-8-enyl) phenol (3), which were found for the first time in the natural source. The equal mixture of compounds 1 and 2 exhibited potent inhibitory activity against all tested Gram-positive bacterial strains (Enterococcus faecalis, Micrococcus luteus, Staphylococcus epidermidis and Staphylococcus aureus) with inhibitory zones of 12.2–22.1 mm, whereas each single compound showed weaker activity than the mixture of 1 and 2. However, compound 3 strongly inhibited (29.9 ± 1.8) the growth of M. luteus. The presence of salicylic acid with the unsaturated aliphatic side chain is essential for the antibacterial activity strength of phenolic lipid molecules.     

Synthesis and anti-inflammatory activity of 2-oxo-2H-chromenyl and 2H-chromenyl-5-oxo-2,5-dihydrofuran-3-carboxylates

Cycloaddition reaction of 4-chloro-2-oxo-2H-chromene-3-carbaldehydes (3a-g) and 4-chloro-2H-chromene-3-carbaldehydes (7a-h) with activated alkynes (4a-b) provided the 2-oxo-2H-chromenyl-5-oxo-2,5-dihydrofuran-3-carboxylates (5a-n) and 2H-chromenyl-5-oxo-2,5-dihydrofuran-3-carboxylates (8a-p). All the prepared compounds were screened for anti-inflammatory activity. In vitro anti-inflammatory activity data demonstrated that the compounds 5g, 5i, 5k-l and 8f are effective among the tested compounds against TNF-α (1.108 ± 0.002, 0.423 ± 0.022, 0.047 ± 0.001, 0.070 ± 0.002 and 0.142 ± 0.001 µM) in comparison with standard compound Prednisolone (0.033 ± 0.002 µM). Based on in vitro results, three compounds (5i, 5k and 8f) have been selected for in vivo experiments and these compounds are identified as better compounds with respect to anti-inflammatory activity in LPS induced mice model. Compound 5i was identified as potent and showed significant reduction in TNF-α and IL-6.     

New 30-norlupane derivatives through chemical-microbial semi-synthesis of betulinic acid and their neuroprotective effect

In this study, seven 30-norlupane derivatives (2–8) was obtained from the chemical oxidation of betulinic acid followed by biotransformation via Bacillus megaterium CGMCC 1.1741. And metabolites 2–4 and 6–8 were newly identified products. In the first step, betulinic acid was chemically oxidized to platanic acid (1). Following the chemical oxidation, B. megaterium catalyzed the hydroxylation at C-7, C-11, C-15 and C-23 of platanic acid (1) as well as the oxidation of C-3 hydroxyl group. Compared to the labor-intensive isolation from natural plants, this chemical-microbial semi-synthesis is more capable to provide increased structural diversity of oxygenated 30-norlupane. Finally, the potential neuroprotective effect of the derivatives was assessed on neuron-like PC12 cells induced by cobalt chloride (CoCl₂). Metabolite 6 showed a potent neuroprotective activity.     

Microbial alcohol dehydrogenase screening for enantiopure lactone synthesis: Down-stream process from microtiter plate to bench bioreactor

One-pot conversion with whole cells of bacteria was performed for biooxidation of meso monocyclic (3a–b) and bicyclic diols (3c–e) into corresponding chiral lactones of bicyclo[4.3.0]nonane structure (2a–b) as well as exo- and endo-bridged lactones with the structure of [2.2.1] (3c–d) and [2.2.2] (3e). Micrococcus sp. DSM 30771 was selected as biocatalyst with significant alcohol dehydrogenase activity. Among tested strains, microbial oxidation of meso diols 3a–e catalyzed by Micrococcus sp. afforded enantiomerically pure ((+)-(2S,3R)-2c (ee = 99%), (+)-(2S,3R)-2e (ee = 99%)) or enriched ((+)-(1S,5R)-2a (ee = 90%), (−)-(1S,5R)-2b (ee = 86%), (+)-(2S,3R)-2d (ee = 80%)) lactone moieties. Comparative study with respect to microbial cultivation as well as biooxidation was undertaken to verify agreement of secondary metabolite biosynthesis in different scales: from MTP (4 mL), across shake flask (100 mL) till bioreactor (4 L). The results from biotransformations showed quite similar dependence in oxidation of all substrates 3a–e in MTP and flasks as well, thereby confirmed the validity and reasonable approach of using MTP for preliminary studies.     

A new cerebroside from the twigs of Lindera glauca (Sieb. et Zucc.) Blume

Lindera glauca (Sieb. et Zucc.) Blume (Lauraceae) has been used to treat rheumatic arthritis, stroke, and cardiac pain. Phytochemical investigation of twigs of L. glauca (Sieb. et Zucc.) Blume resulted in the isolation and identification of a new cerebroside, glaucerebroside (1). The structure of 1 was elucidated by a combination of extensive spectroscopic analyses, including extensive 2D NMR, HR-MS, chemical reactions, and LC/MS analysis. Compound 1 is a relatively rare cerebroside with l-threo-configuration of the sphingosine part. This is the second example of identification of a cerebroside from the family Lauraceae. Compound 1 significantly inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated BV-2 cells, with an IC₅₀ value of 23.84 μM without inducing cell toxicity. This study suggests that glaucerebroside (1) can be an excellent candidate for development of novel anti-neuroinflammatory agents.     

New oleanane saponins from Schefflera kwangsiensis

Four new oleanane-type triterpenoid saponins, schefflesides I–L (1–4), were isolated from the aerial parts of Schefflera kwangsiensis. Their structures were established as oleanolic acid 3-O-β-d-glucopyranosyl (1 → 2) [α-l-arabinopyranosyl (1 → 4)]-β-d-(6-O-methyl) glucuronopyranoside (1), 22α-hydroxyoleanolic acid 3-O-α-l-arabinopyranosyl (1 → 4)-β-d-glucuronopyranoside (2), hederagenin 3-O-α-l-arabinopyranosyl (1 → 4)-β-d-glucuronopyranoside (3) and oleanolic acid 28-O-β-d-glucopyranosyl (1 → 2)-β-d-glucuronopyranosyl ester (4) by spectroscopic analyses (HRESIMS, 1D and 2D NMR) and chemical methods.