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International Journal of Organic Chemistry 2024年第3期14卷 107-122页

作者： Marwa Dhiabi Sirine Karoui Mehdi Fakhfakh Souhir Abid Emmanuelle Limanton Rémy le Guével Thierry Charlier Ludovic Paquin jean-pierre Bazureau Houcine Ammar Laboratoire de Chimie Applique: Htrocycles Corps et Polymres Facult des Sciences de Sfax Universit de Sfax Sfax Tunisie Institut des Sciences Chimiques de rennes Universit de Rennes Campus de Beaulieu Rennes Cedex France Department of Chemistry (Science and Arts): Al Qurayat Al-Jouf University Al Jawf Saudi Arabia S2Wave Platform ScanMAT UAR CNRS Universit de Rennes Campus de Beaulieu Rennes Cedex France ImPACcell Platform Biosit SFR UMS CNRS Inserm Campus de Villejean Rennes France Institut de recherche en Sant Environnement et Travail IRSET Inserm UMR_S Rennes France

The synthesis of new 4-imino-4H-chromeno[2,3-d]pyrimidin-3(5H)-amine in four steps including one step under microwave dielectric heating is reported. The structural identity of the synthesized compounds was established according to their spectroscopic analysis, such as FT-IR, NMR and mass spectroscopy. These new compounds were tested for their antiproliferative activities on seven representative human tumoral cell lines (Huh7 D12, Caco2, MDA-MB231, MDA-MB468, HCT116, PC3 and MCF7) and also on fibroblasts. Among them, only the compounds 6c showed micromolar cytotoxic activity on tumor cell lines (1.8 50 50 > 25 μM). Finally, in silico ADMET studies ware performed to investigate the possibility of using of the identified compound 6c as potential anti-tumor compound.

关键词： 2-Amino-4H-Chromene 4H-Chromeno[2 3-d]Pyrimidin-3(5H)-Amine Microwave Irradiation Tumoral Cell Line in Silico ADMET

Matrix Assisted Laser Desorption Ionization Time of Flight(MALDI-TOF)-Mass Spectrometry and^(13)C-NMR-Identified New Compounds in Paraberlinia bifoliolata(Ekop-Beli)Bark Tannins

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Journal of renewable Materials 2024年第3期12卷 553-568页

作者： Liliane Nga Benoit Ndiwe Achille Bernard Biwolé Antonio pizzi jean Jalin Eyinga Biwole Joseph Zobo Mfomo Laboratory of Forest resources and Wood Valorization Training Unit in Engineering SciencesPost Graduate School of Fundamental and Applied SciencesUniversity of DoualaP.O.Box 1872DoualaCameroun Laboratory of Mechanics Training Unit in Engineering SciencesPost Graduate School of Fundamental and Applied SciencesUniversity of DoualaP.O.Box 2701DoualaCameroun Laboratory of Studies and research on Wood Material(leRMAB) University of LorraineNancyFrance

Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial *** discovery of new tannins is therefore *** aim of this work was to contribute to the understanding of the properties of Paraberlinia bifoliolata tannin by Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy MALDI-TOF/MS and Carbon 13 Nuclear Magnetic resonance(13C NMR).The chemical composition of tannin extracted from Paraberlinia bifoliolata bark was determined,as was the mechanical strength of the resin hardened with Acacia nilotica *** by successive water extraction was 35%.MALDI-TOF/MS analysis revealed the presence of three new compounds in this tannin,previously unknown in this family of *** are 3-hydroxyproline acid,N-methyl-4-hydroxypipecolic acid and N-methyl-5-dihydroxypipecolic *** identification of the above molecules means that this tannin can be used for industrial applications,as a resin in the manufacture of particleboard and in the formulation of green corrosion *** information is reinforced by 13C NMR spectrometry,which indicates the presence of several polyflavonoid units,confirming the condensed nature of the *** analysis of the resin formed by the purified tannin of Paraberlinia bifoliolata to which a vegetal biohardener has been added provided a Modulus of Elasticity(MOE)value of 4840 MPa at 150℃,confirming its possible use as a binder resin in the manufacture of wood panels as well as for the formulation of a corrosion inhibitor.

关键词： Tannin Paraberlinia bifoliolata Central African wood species MALDI-TOF/MS 13C NMR bark extracts thermomechanical behaviour wood-binder

Phytochemical Screening, Study of Acute Toxicity and Hypoglycemic and Antihyperglycemic Activities of Silver Nanoparticles from Guibourtia tessmannii (Harms) J. leonard (Caesalpiniaceae)

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Open Journal of Applied Sciences 2024年第1期14卷 118-130页

作者： Ngoulé Charles Christian Eya’ane Meva François Sone Enone Bertin Ngo Nyobe Biwole Caroline Tankeu Séverin Elisée Songue Pascal Nguene jean pierre Etame-Loe Gisèle Department of Pharmaceutical Sciences Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Department of Biology of Plant Organisms Faculty of Sciences University of Douala Douala Cameroon

According to the World Health Organization, diabetes affects approximately 347 million people worldwide. Its management is not within the reach of all social classes, therefore medicinal plants are still the first resort for many populations in Africa. The biological material used in this study was the trunk bark of Guibourtia tessmannii. 50 g of trunk bark powder were decocted in 500 ml of distilled water for 5 minutes were carried out. The method used for the synthesis of silver nanoparticles (AgNps) was an organometallic bio-reduction of silver nitrate salts mediated by various secondary metabolites contained in the plant extract. The study of the toxicity acute was conducted according to guideline 423 of the OECD protocol. The pharmacological activities were each carried out with 28 female rats divided into 7 groups of four rats. It was a question for the hypoglycemic activity of administering various doses of silver nanoparticles and other substances to the rats thirty minutes after the carbohydrate intake and for the anti-hyperglycemic activity of administering the same substances to the rats thirty minutes before the carbohydrate intake. The extraction yield was 8.76%. Only the alkaloid test was negative. After acute toxicity study, the LD50 was greater than 2000 mg/kg. Blood sugar tests revealed that glibenclamide 5 mg/kg, which is the reference molecule, lowered blood sugar more than the other treatments applied in the other batches. It was followed by treatment with silver nanoparticles at a dose of 400 μg/kg in both tests. It was therefore concluded that silver nanoparticles from G. tessmannii are good for the formulation of improved traditional medicines and bring up their afficacity .

关键词： Guibourtia tessmannii Nanoparticles Hypoglycemia Anti-Hyperglycemia

Supervised learning Method: Critical Analysis and Updating of Cubing Rate Formulas for Determining Bark Masses of Prunus africana (Hook. f.) Kalkman (Rosaceae) in Cameroon

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Open Journal of Forestry 2024年第3期14卷 346-368页

作者： Armand Ndedy Bile Alain Mpouam Benoit Fouadjio Lorette Guedeu Kambale Muhesi Steve Tassiamba Paulette Kouam Eric Wete Marius Ela Michèle Yimga Joseph Ambara Louis Aimé Fono jean Lagarde Betti Department of Plant Biology Faculty of Science The University of Douala Douala Cameroon Department of Wood and Forest Sciences ISABEE University of Bertoua Bertoua Cameroon Department of Water and Forests Higher Institute of Agronomic Veterinary and Forestry Studies of Butembo Butembo Democratic Republic of Congo Department of Forestry Faculty of Agronomy and Agricultural Sciences University of Dschang Dschang Cameroon Department of Biology and Plant Faculty of Sciences University of Maroua Maroua Cameroon Deutsche Gresellschaft fur Internationale Zusammenarbeit GmbH (GIZ) Bertoua Cameroon Department of Mathematics and Computer Science Faculty of Science The University of Douala Douala Cameroon

The stem barks of Prunus africana are used in the treatment of the benign prostate. Cameroon is one of the important exporters of the barks. Despite the important measures adopted in Cameroon for sustaining its harvesting, some many chalenges still remain. The objective of this work is to refine the forest management parameters in relation to P. africana in the regions of Adamaoua and the South-West by developing a volume rate which makes it possible to estimate the production for a new stem. The work took place in two phases: in the South-West in 2010 and in Adamaoua in 2011. Data collection used the semi-direct method, while the cubing equation was deduced by the multiple linear regression method. Two models for volume estimation and three models for mass prediction were developed. The predictive parameters retained are diameter, height of the bole and thickness of the bark. results show that the average mass of the dry bark for a given P. africana tree species is 27.55 ± 14.44 kg and this varies according to the site. The strong adjusted coefficient of determination (adjusted R2) observed illustrates the reliability of the proposed models. These models provide a reliable tool that can be adopted as a standard in Cameroon for P. africana.

关键词： Prunus africana Prostate Quota Mass Model Sustainable Management

Efficacy and tolerability of chitin-glucan combined with simethicone(GASTRAP^(■)DIreCT)in irritable bowel syndrome:A prospective,open-label,multicenter study

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World Journal of Gastrointestinal Pharmacology and Therapeutics 2024年第3期15卷 10-22页

作者： Nathalie Talbodec Pauline le Roy Peggy Fournier Benoit lesage Elodie lepoutre François Castex jean Michel Godchaux Lionel Vandeville Benjamin Bismuth Xavier lesage Pauline Bayart Michael Genin Christel Rousseaux Veronique Maquet Salvatore Modica pierre Desreumaux Caroline Valibouze Department of Gastroenterology Hôpital privéLe BoisLille 59000France Department of Gastroenterology Hôpital privéde Villeneuve d’AscqVilleneuve d’Ascq 59650France Univ.Lille CHU LilleULR 2694–METRICSÉvaluation des Technologies de Santéet des Pratiques MédicalesLille 59000France Development of Intestinal Biotech 1 Avenue Oscar LambretLille 59045France KitoZyme SA Parc Industriel des hauts Sarts Zone 2Rue de MilmortHerstal 4040Belgium BiOkuris A Parc Industriel des hauts Sarts Zone 2Rue de MilmortHerstal 4040Belgium Department of Hepato-Gastroenterology Lille University HospitalLille 59000France U1286-INFINITE Institute for Translational Research in InflammationUniv.LilleInsermCHU LilleLille 59000France Department of Digestive Surgery and Transplantation Lille University HospitalLille 59037France

BACKGROUND Irritable bowel syndrome(IBS),defined according to the Rome IV diagnostic criteria,is a chronic functional gastrointestinal disorder characterized by recurrent abdominal pain related to altered bowel ***-line recommended treatments are limited to combining drugs targeting predominant symptoms,particularly pain(antispasmodics),constipation(laxatives),and diarrhea(loperamide),yielding only a limited therapeutic ***^(■)DIreCT is a class IIa medical formulation composed of a combination of chitin-glucan and simethicone indicated for the symptomatic treatment of gas-related gastrointestinal disorders by combining different mechanisms of *** To evaluate the efficacy,tolerability,and safety of 4-week GASTRAP^(■)DIreCT treatment in patients with *** In this prospective,multicenter,open-label trial,120 patients with IBS received three sticks of GASTRAP^(■)DIreCT(1.5 g/d of chitin-glucan and 0.75 mg/d of simethicone)per day for 4 *** primary endpoint was the responder rate,defined as the number of patients whose abdominal pain score decreased by≥30%from baseline to week(W)*** analysis was performed using the per-protocol *** symptoms,impact of global symptoms on daily life,change in stool consistency,and improvement in defecatory disorders were *** Overall,100 patients were *** W4,67%(95%CI:57-75)showed improvement in abdominal pain(score:5.8±2.4 vs 2.9±2.0,Pre observed for bloating[8.0±1.7 vs 4.7±2.9,Presponders],abdominal distension[7.2±2.1 vs 4.4±3.1,Presponders],and impact of global symptoms on daily life[7.1±2.0 vs 4.6±2.9,Presponders].Stool consistency improved in most patients(90%and 57%for patients with liquid and hard stools,respectively).Overall,42%of patients with defecatory disorders reported very much/considerable improvements by *** severe adverse event occurred,and tolerabil

关键词： Chitin-glucan Irritable bowel syndrome Abdominal pain Flatulence Defecatory disorders Stool consistency Natural non-pharmacological treatment

Silicon slow light photonic crystals structures:present achievements and future trends

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Frontiers of Optoelectronics 2011年第3期4卷 243-253页

作者： Eric CASSAN Xavier le ROUX Charles caer Ran HAO Damien BERNIER Delphine MARRIS-MORINI Laurent VIVIEN Institut d'Electronique Fondamentale Université Paris-Sud CNRS UMR 8622

Slow light in planar photonic structures has attracted for some years an increasing interest due to amazing physical effects it allows or reinforces and to the degrees of freedom it raises for designing new optical functions. Controlling light group velocity is achieved through the use of periodical optical media obtained by nano-structuration of semiconductor wafers at the scale of light wavelength: the so-called photonic crystals. This article reviews present achievements realized in the field of slow light photonic bandgap structures, including the physical principles of slow light to the description of the most advanced integrated optical devices relying on *** and current hot topics related to slow light are discussed to highlight the balance between the advantages and drawbacks of using slow waves in integrated photonic structures. Then, future trends are described, which is focused on the use of slow wave slot waveguides for nonlinear optics and bio-photonic applications.

关键词： slow light photonic crystals silicon photonics integrated optical devices

Effect of probiotic administration on the intestinal microbiota, current knowledge and potential applications

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World Journal of Gastroenterology 2014年第44期20卷 16518-16528页

作者： Alejandra de Moreno de le Blanc jean Guy le Blanc Centro de referencia para Lactobacilos San Miguel de Tucuman

Although it is now known that the human body is colonized by a wide variety of microbial populations in different parts(such as the mouth, pharynx and respiratory system, the skin, the gastro- and urogenital tracts), many effects of the complex interactions between the human host and microbial symbionts are still not completely understood. The dysbiosis of the gastrointestinal tract microbiota is considered to be one of the most important contributing factors in the development of many gastrointestinal diseases such as inflammatory bowel disease, irritable bowel syndrome and colorectal cancer, as well as systemic diseases like obesity, diabetes, atherosclerosis and non-alcoholic fatty liver disease. Fecal microbial transplantations appear to be promising therapies for dysbiosis-associated diseases; however, probiotic microorganisms have been growing in popularity due to increasing numbers of studies proving that certain strains present health promoting properties, among them the beneficial balance of the intestinal microbiota. Inflammatory bowel diseases andobesity are the pathologies in which there are more studies showing this beneficial association using animal models and even in human clinical *** this review,the association of the human gut microbiota and human health will be discussed along with the benefits that probiotics can confer on this symbiotic activity and on the prevention or treatment of associated diseases.

关键词： Probiotics Dysbiosis Gut microbiota Symbiosis Treatment

Does insect mother know under what conditions it will make their offspring live？

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Insect Science 2017年第1期24卷 141-149页

作者： Fatemeh Kohandani Guillaume jean le Goff Thierry Hance Earth and Life Institute Biodiversity Research Centre Universite Catholique de Louvain 4 Place Croix du Sud 1348 Louvain-la-Neuve Belgium

According to the optimal oviposition theory, the larval success of insects depends on the oviposition site selection by females. Females are expected to choose a site with many resources and few competitors or predators to allow the best performance for their progeny, assuming that ＂mother knows best.＂ However, this is not systematically observed. The Aphidoletes aphidimyza larvae are generalist aphid predators and females consequently lay their eggs near or inside aphid colonies. The goal of this study was to investigate the impact ofintraspecific competition on oviposition behavior of A. aphidimyza females. First, we counted the number of eggs laid by a female on a leaf with 20 aphids, in the presence of 0, 2, 4, or 6 conspecific eggs or in the absence of eggs but in presence of 3 virgin females. The same experiment was also performed under choice condition with 2 oviposition sites. Our results show that the presence of low densities ofconspecific eggs, or the presence of conspecific females, have no significant impact on the number of eggs laid by A. aphidimyza females. One of the hypotheses advanced to explain these results is the advantages of conspecifics presence. At low densities, the presence of eggs on an oviposition site can indicate the suitability of the site for the females. The conspecific presence can also insure a dilution effect against predator and increase the presence of potential mating partners for this monogenic species.

关键词： Aphidoletes aphidimyza clutch size dilution effect intraspecific competition optimal oviposition predatory larvae

Differences in egg hatching time between cyclical and obligate parthenogenetic lineages of aphids

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Insect Science 2019年第1期26卷 135-141页

作者： Charles-Antoine Dedryver Joel Bonhomme jean-Francois le Gallic jean-Christophe Simon Unite Mixte de recherche IGEPP 1349 INRAIAgrocampus OuestlUniversite Rennes 1Le Rheu cedexFrance

Many aphid species exhibit a variation in reproductive mode which is influenced by winter climate regimes,with cyclical parthenogenetic (CP)lines dominating in cold winter areas (because they produce cold-resistant eggs)and obligate parthenogenetic (OP) ones in mild winter regions (because of their parthenogenetic overwintering).Genetic studies on several aphid species have shown that the OP trait can be transmitted during sexual events involving the 2 types of *** genetic system could be considered as a local safeguarding mechanism for OP alleles in case severe frost would have killed all parthenogenetically overwintering ***,this strategy would only be efficient in restoring local polymorphism in breeding systems if the newly hatched OP recombinants remain competitive over their CP *** this study we compared egg hatching sequences of CP and OP F1 clones from several crosses obtained for 2 cereal aphid species,Sitobion avenae (constant 5℃,8 h of light)and Rhopalosiphum padi (winter outdoor conditions).For ***,we obtained F1 offspring from 6 crosses, involving 4 clones while in *** F1 were obtained from 11 crosses involving 14 clones. We showed that in both species proportions of OP clones were higher in the first half of the progeny relative to the second *** addition,F1 OP clones hatched in the mean about a week earlier than their CP sibs,which gives them a demographic advantage at the start of the growth *** then discussed the consequences of this fitness advantage for the maintenance and spread of the OP trait in aphid populations.

关键词： asexuality diapauses genetic variation insects overwintering strategies reproductive mode

Irrigated Agriculture Facing the Challenge of Climate Change: Adaptation Strategies for Farmers in the Irrigated Perimeters of Môle Saint-Nicolas, Haiti

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American Journal of Climate Change 2024年第3期13卷 477-498页

作者： Frantz Mial jean-François Bissonnette Marc-André Bourgault Meryem Qacami Department of Geography Laval University Quebec Canada

Môle Saint-Nicolas, like all other communes in the republic of Haiti, faces increasing climate variability, impacting agricultural production and water resources. Consequently, there is a pressing need for adaptation to these climatic changes. This research aims to showcase the adaptation strategies deployed by farmers to cope with the increasing climate variability. Surveys were conducted through group and individual discussions with a randomly selected cohort of 150 farmers. Two types of analysis were performed: quantitative and qualitative. The quantitative data analysis was conducted using Statistical Package for the Social Sciences (SPSS) software. The findings reveal that farmers have perceived changes in rainfall patterns, temperature, wind, and their environment. These changes manifest as irregular rainfall, higher temperatures, prolonged drought periods, violent winds accompanied by rain, premature cessation of rains, and reduced flow from water sources. In response, the most common adaptation strategies adopted include selecting new cultivars, early-maturing varieties, crop rotation and diversification, canal dredging, new soil preparation methods, upstream water source protection, and micro-watershed management. The significance of this research lies in its contribution to enhancing farmers’ adaptive capacities by alerting stakeholders in the irrigated perimeters about the consequences of climate change, thereby incorporating the real needs of farmers in future projects.

关键词： Climate Change Perception Adaptation Agriculture Irrigated Perimeter