1,103 research outputs found

    Low efficacy of the combination artesunate plus amodiaquine for uncomplicated falciparum malaria among children under 5 years in Kailahun, Sierra Leone.

    Get PDF
    OBJECTIVE: In 2004, Sierra Leone adopted artesunate plus amodiaquine as first-line antimalarial treatment. We evaluated the efficacy of this combination in Kailahun, where a previous study had shown 70.2% efficacy of amodiaquine in monotherapy. METHODS: Method and outcome classification of the study complied with WHO guidelines. Children 6-59 months with uncomplicated malaria were followed-up for 28 days. PCR genotyping was used to distinguish recrudescence from reinfection. Reinfections were reclassified as cured. RESULTS: Of 172 children who were referred to the study clinic, 126 satisfied inclusion criteria and were enrolled. No early treatment failures were reported. The day 14, efficacy was 98.2% (95% CI: 93.8-99.8). Of 65 recurrent parasitaemias analysed by PCR, 17 were recrudescences. The PCR-adjusted day 28 efficacy was 84.5% (95% CI: 76.4-90.7). All true failures occurred in the last 8 days of follow-up. Of 110 children who completed the 28-day follow-up, 54 (49.1%) experienced a novel infection. CONCLUSION: The efficacy of this combination was disappointing. The high reinfection rate suggested little prophylactic effect. In Kailahun a more efficacious combination might be necessary in the future. The efficacy of AS + AQ needs to be monitored in Kailahun and in the other regions of Sierra Leone

    Getting DNA twist rigidity from single molecule experiments

    Get PDF
    We use an elastic rod model with contact to study the extension versus rotation diagrams of single supercoiled DNA molecules. We reproduce quantitatively the supercoiling response of overtwisted DNA and, using experimental data, we get an estimation of the effective supercoiling radius and of the twist rigidity of B-DNA. We find that unlike the bending rigidity, the twist rigidity of DNA seems to vary widely with the nature and concentration of the salt buffer in which it is immerged

    Detection of skewed X-chromosome inactivation in Fragile X syndrome and X chromosome aneuploidy using quantitative melt analysis.

    Get PDF
    Methylation of the fragile X mental retardation 1 (FMR1) exon 1/intron 1 boundary positioned fragile X related epigenetic element 2 (FREE2), reveals skewed X-chromosome inactivation (XCI) in fragile X syndrome full mutation (FM: CGG > 200) females. XCI skewing has been also linked to abnormal X-linked gene expression with the broader clinical impact for sex chromosome aneuploidies (SCAs). In this study, 10 FREE2 CpG sites were targeted using methylation specific quantitative melt analysis (MS-QMA), including 3 sites that could not be analysed with previously used EpiTYPER system. The method was applied for detection of skewed XCI in FM females and in different types of SCA. We tested venous blood and saliva DNA collected from 107 controls (CGG < 40), and 148 FM and 90 SCA individuals. MS-QMA identified: (i) most SCAs if combined with a Y chromosome test; (ii) locus-specific XCI skewing towards the hypomethylated state in FM females; and (iii) skewed XCI towards the hypermethylated state in SCA with 3 or more X chromosomes, and in 5% of the 47,XXY individuals. MS-QMA output also showed significant correlation with the EpiTYPER reference method in FM males and females (P < 0.0001) and SCAs (P < 0.05). In conclusion, we demonstrate use of MS-QMA to quantify skewed XCI in two applications with diagnostic utility

    Changes in cocoa properties induced by the alkalization process: A review

    Full text link
    [EN] Alkalization, also known as "Dutching," is an optional, but very useful, step taken in the production chain of cocoa to darken its color, modify its taste, and increase natural cocoa solubility. Over the years, various attempts have been made to design new and more effective alkalization methods. Moreover, different authors have attempted to elucidate the impact of alkalization on the physicochemical, nutritional, functional, microbiological, and sensory characteristics of alkalized cocoa. The aim of this review is to provide a clear guide about not only the conditions that can be applied to alkalize cocoa, but also the reported effects of alkalization on the nutritional, functional, microbiological, and sensory characteristics of cocoa. The first part of this review describes different cocoa alkalization systems and how they can be tuned to induce specific changes in cocoa properties. The second part is a holistic analysis of the effects of the alkalization process on different cocoa features, performed by emphasizing the biochemistry behind all these transformations.European Regional Development Fund, Grant/Award Number: Project RTC-2016-5241-2; Ministerio deEconomia y Competitividad, Grant/Award Number: Project RTC-2016-5241-2Valverde-Garcia, D.; Pérez-Esteve, É.; Barat Baviera, JM. (2020). Changes in cocoa properties induced by the alkalization process: A review. Comprehensive Reviews in Food Science and Food Safety. 19(4):2200-2221. https://doi.org/10.1111/1541-4337.12581S22002221194Ilesanmi Adeyeye, E. (2016). Proximate, Mineral And Antinutrient Compositions Of Natural Cocoa Cake, Cocoa Liquor And Alkalized Cocoa Powders. Journal of Advanced Pharmaceutical Science And Technology, 1(3), 12-28. doi:10.14302/issn.2328-0182.japst-15-855Ajandouz, E. H., Tchiakpe, L. S., Ore, F. D., Benajiba, A., & Puigserver, A. (2001). Effects of pH on Caramelization and Maillard Reaction Kinetics in Fructose-Lysine Model Systems. Journal of Food Science, 66(7), 926-931. doi:10.1111/j.1365-2621.2001.tb08213.xAndres-Lacueva, C., Monagas, M., Khan, N., Izquierdo-Pulido, M., Urpi-Sarda, M., Permanyer, J., & Lamuela-Raventós, R. M. (2008). Flavanol and Flavonol Contents of Cocoa Powder Products: Influence of the Manufacturing Process. Journal of Agricultural and Food Chemistry, 56(9), 3111-3117. doi:10.1021/jf0728754Andruszkiewicz, P. J., D’Souza, R. N., Altun, I., Corno, M., & Kuhnert, N. (2019). Thermally-induced formation of taste-active 2,5-diketopiperazines from short-chain peptide precursors in cocoa. Food Research International, 121, 217-228. doi:10.1016/j.foodres.2019.03.015Aprotosoaie, A. C., Luca, S. V., & Miron, A. (2015). Flavor Chemistry of Cocoa and Cocoa Products-An Overview. Comprehensive Reviews in Food Science and Food Safety, 15(1), 73-91. doi:10.1111/1541-4337.12180Aremu, C. Y., Agiang, M. A., & Ayatse, J. O. I. (1995). Nutrient and antinutrient profiles of raw and fermented cocoa beans. Plant Foods for Human Nutrition, 48(3), 217-223. doi:10.1007/bf01088443Bandi J. P. Kubicek K. &Raboud P. B.(1984).Installation for solubilizing cocoa. US4438681A.Baigrie, B. D. (1994). Cocoa flavour. Understanding Natural Flavors, 268-282. doi:10.1007/978-1-4615-2143-3_17Bartella, L., Di Donna, L., Napoli, A., Siciliano, C., Sindona, G., & Mazzotti, F. (2019). A rapid method for the assay of methylxanthines alkaloids: Theobromine, theophylline and caffeine, in cocoa products and drugs by paper spray tandem mass spectrometry. Food Chemistry, 278, 261-266. doi:10.1016/j.foodchem.2018.11.072Bauermeister J.(1989).Process for making cacao powder by disagglomeration and cacao powder granulate by subsequent agglomeration. EP0310790A2.Beg, M. S., Ahmad, S., Jan, K., & Bashir, K. (2017). Status, supply chain and processing of cocoa - A review. Trends in Food Science & Technology, 66, 108-116. doi:10.1016/j.tifs.2017.06.007Biehl B.(1986).Cocoa fermentation and problem of acidity over‐fermentation and low cocoa flavour.Selangor Malaysia: Incorporated Society of Planters.Serra Bonvehí, J., & Ventura Coll, F. (2000). Evaluation of purine alkaloids and diketopiperazines contents in processed cocoa powder. European Food Research and Technology, 210(3), 189-195. doi:10.1007/pl00005510Borthwick, A. D., & Da Costa, N. C. (2015). 2,5-diketopiperazines in food and beverages: Taste and bioactivity. Critical Reviews in Food Science and Nutrition, 57(4), 718-742. doi:10.1080/10408398.2014.911142Chalin M. L.(1972).Method of dutching cocoa. US3868469A.Rainer Cremer, D. (2000). The reaction kinetics for the formation of Strecker aldehydes in low moisture model systems and in plant powders. Food Chemistry, 71(1), 37-43. doi:10.1016/s0308-8146(00)00122-9De Vuyst, L., & Weckx, S. (2016). The cocoa bean fermentation process: from ecosystem analysis to starter culture development. Journal of Applied Microbiology, 121(1), 5-17. doi:10.1111/jam.13045Del Rio, D., Costa, L. G., Lean, M. E. J., & Crozier, A. (2010). Polyphenols and health: What compounds are involved? Nutrition, Metabolism and Cardiovascular Diseases, 20(1), 1-6. doi:10.1016/j.numecd.2009.05.015Domínguez-Rodríguez, G., Marina, M. L., & Plaza, M. (2017). Strategies for the extraction and analysis of non-extractable polyphenols from plants. Journal of Chromatography A, 1514, 1-15. doi:10.1016/j.chroma.2017.07.066El Gharras, H. (2009). Polyphenols: food sources, properties and applications - a review. International Journal of Food Science & Technology, 44(12), 2512-2518. doi:10.1111/j.1365-2621.2009.02077.xEllis L. D.(1990).Process for making dark cocoa. US5114730A.Ellis L. D. (1992).Process for making dark cocoa. US5114730A.Lu, F., Rodriguez-Garcia, J., Van Damme, I., Westwood, N. J., Shaw, L., Robinson, J. S., … Charalampopoulos, D. (2018). Valorisation strategies for cocoa pod husk and its fractions. Current Opinion in Green and Sustainable Chemistry, 14, 80-88. doi:10.1016/j.cogsc.2018.07.007Franco, R., Oñatibia-Astibia, A., & Martínez-Pinilla, E. (2013). Health Benefits of Methylxanthines in Cacao and Chocolate. Nutrients, 5(10), 4159-4173. doi:10.3390/nu5104159Germann, D., Stark, T. D., & Hofmann, T. (2019). Formation and Characterization of Polyphenol-Derived Red Chromophores. Enhancing the Color of Processed Cocoa Powders: Part 1. Journal of Agricultural and Food Chemistry, 67(16), 4632-4642. doi:10.1021/acs.jafc.9b01049Germann, D., Stark, T. D., & Hofmann, T. (2019). Formation and Characterization of Polyphenol-Derived Red Chromophores. Enhancing the Color of Processed Cocoa Powders: Part 2. Journal of Agricultural and Food Chemistry, 67(16), 4643-4651. doi:10.1021/acs.jafc.9b01050Gobert, J., & Glomb, M. A. (2009). Degradation of Glucose: Reinvestigation of Reactive α-Dicarbonyl Compounds†. Journal of Agricultural and Food Chemistry, 57(18), 8591-8597. doi:10.1021/jf9019085Gu, L., House, S. E., Wu, X., Ou, B., & Prior, R. L. (2006). Procyanidin and Catechin Contents and Antioxidant Capacity of Cocoa and Chocolate Products. Journal of Agricultural and Food Chemistry, 54(11), 4057-4061. doi:10.1021/jf060360rGültekin-Özgüven, M., Berktaş, I., & Özçelik, B. (2016). Change in stability of procyanidins, antioxidant capacity and in-vitro bioaccessibility during processing of cocoa powder from cocoa beans. LWT - Food Science and Technology, 72, 559-565. doi:10.1016/j.lwt.2016.04.065Hagerman, A. E. (1992). Tannin—Protein Interactions. Phenolic Compounds in Food and Their Effects on Health I, 236-247. doi:10.1021/bk-1992-0506.ch019Holkar, C. R., Jadhav, A. J., & Pinjari, D. V. (2019). A critical review on the possible remediation of sediment in cocoa/coffee flavored milk. Trends in Food Science & Technology, 86, 199-208. doi:10.1016/j.tifs.2019.02.035Huang, Y., & Barringer, S. A. (2010). Alkylpyrazines and Other Volatiles in Cocoa Liquors at pH 5 to 8, by Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS). Journal of Food Science, 75(1), C121-C127. doi:10.1111/j.1750-3841.2009.01455.xHurst, W. J., Krake, S. H., Bergmeier, S. C., Payne, M. J., Miller, K. B., & Stuart, D. A. (2011). Impact of fermentation, drying, roasting and Dutch processing on flavan-3-ol stereochemistry in cacao beans and cocoa ingredients. Chemistry Central Journal, 5(1). doi:10.1186/1752-153x-5-53International Cocoa Organization(2017).Annual report 2014/2015 Retrieved fromhttps://www.icco.org/about-us/international-cocoa-agreements/cat_view/1-annual-report.html.Mazor Jolić, S., Radojčić Redovniković, I., Marković, K., Ivanec Šipušić, Đ., & Delonga, K. (2011). Changes of phenolic compounds and antioxidant capacity in cocoa beans processing. International Journal of Food Science & Technology, 46(9), 1793-1800. doi:10.1111/j.1365-2621.2011.02670.xKofink, M., Papagiannopoulos, M., & Galensa, R. (2007). (-)-Catechin in Cocoa and Chocolate: Occurence and Analysis of an Atypical Flavan-3-ol Enantiomer. Molecules, 12(7), 1274-1288. doi:10.3390/12071274Kongor, J. E., Hinneh, M., de Walle, D. V., Afoakwa, E. O., Boeckx, P., & Dewettinck, K. (2016). Factors influencing quality variation in cocoa (Theobroma cacao) bean flavour profile — A review. Food Research International, 82, 44-52. doi:10.1016/j.foodres.2016.01.012Kopp G. M. Hennen J. C. Seyller M. &Brandstetter B.(2010).Process for producing high flavour cocoa. EP2241190A1.Kruszewski, B., & Obiedziński, M. W. (2020). Impact of Raw Materials and Production Processes on Furan and Acrylamide Contents in Dark Chocolate. Journal of Agricultural and Food Chemistry, 68(8), 2562-2569. doi:10.1021/acs.jafc.0c00412Lan, X., Liu, P., Xia, S., Jia, C., Mukunzi, D., Zhang, X., … Xiao, Z. (2010). Temperature effect on the non-volatile compounds of Maillard reaction products derived from xylose–soybean peptide system: Further insights into thermal degradation and cross-linking. Food Chemistry, 120(4), 967-972. doi:10.1016/j.foodchem.2009.11.033Li, Y., Feng, Y., Zhu, S., Luo, C., Ma, J., & Zhong, F. (2012). The effect of alkalization on the bioactive and flavor related components in commercial cocoa powder. Journal of Food Composition and Analysis, 25(1), 17-23. doi:10.1016/j.jfca.2011.04.010Li, Y., Zhu, S., Feng, Y., Xu, F., Ma, J., & Zhong, F. (2013). Influence of alkalization treatment on the color quality and the total phenolic and anthocyanin contents in cocoa powder. Food Science and Biotechnology, 23(1), 59-63. doi:10.1007/s10068-014-0008-5Lima, L. J. R., Kamphuis, H. J., Nout, M. J. R., & Zwietering, M. H. (2011). Microbiota of cocoa powder with particular reference to aerobic thermoresistant spore-formers. Food Microbiology, 28(3), 573-582. doi:10.1016/j.fm.2010.11.011MALEYKI, M. J. A., & ISMAIL, A. (2010). ANTIOXIDANT PROPERTIES OF COCOA POWDER. Journal of Food Biochemistry, 34(1), 111-128. doi:10.1111/j.1745-4514.2009.00268.xMartín, M. Á., & Ramos, S. (2017). Health beneficial effects of cocoa phenolic compounds: a mini-review. Current Opinion in Food Science, 14, 20-25. doi:10.1016/j.cofs.2016.12.002Martin, M. A., Goya, L., & Ramos, S. (2013). Potential for preventive effects of cocoa and cocoa polyphenols in cancer. Food and Chemical Toxicology, 56, 336-351. doi:10.1016/j.fct.2013.02.020Méndez-Albores, A., De Jesús-Flores, F., Castañeda-Roldan, E., Arámbula-Villa, G., & Moreno-Martı́nez, E. (2004). The effect of toasting and boiling on the fate of B-aflatoxins during pinole preparation. Journal of Food Engineering, 65(4), 585-589. doi:10.1016/j.jfoodeng.2004.02.024Miller, K. B., Hurst, W. J., Payne, M. J., Stuart, D. A., Apgar, J., Sweigart, D. S., & Ou, B. (2008). Impact of Alkalization on the Antioxidant and Flavanol Content of Commercial Cocoa Powders. Journal of Agricultural and Food Chemistry, 56(18), 8527-8533. doi:10.1021/jf801670pOlam. (2017).The De Zaan cocoa manual. The Netherlands: Archer Daniels Midland Company BV.ODUNS, A. A., & LONGE, O. G. (1998). Nutritive value of hot water- or cocoa-pod ash solution-treated cocoa bean cake for broiler chicks. British Poultry Science, 39(4), 519-525. doi:10.1080/00071669888700Ofosu, I. W., Ankar-Brewoo, G. M., Lutterodt, H. E., Benefo, E. O., & Menyah, C. A. (2019). Estimated daily intake and risk of prevailing acrylamide content of alkalized roasted cocoa beans. Scientific African, 6, e00176. doi:10.1016/j.sciaf.2019.e00176Okiyama, D. C. G., Navarro, S. L. B., & Rodrigues, C. E. C. (2017). Cocoa shell and its compounds: Applications in the food industry. Trends in Food Science & Technology, 63, 103-112. doi:10.1016/j.tifs.2017.03.007Ortega, N., Romero, M.-P., Macià, A., Reguant, J., Anglès, N., Morelló, J.-R., & Motilva, M.-J. (2008). Obtention and Characterization of Phenolic Extracts from Different Cocoa Sources. Journal of Agricultural and Food Chemistry, 56(20), 9621-9627. doi:10.1021/jf8014415Pia, A. K. R., Pereira, A. P. M., Costa, R. A., Alvarenga, V. O., Freire, L., Carlin, F., & Sant’Ana, A. S. (2019). The fate of Bacillus cereus and Geobacillus stearothermophilus during alkalization of cocoa as affected by alkali concentration and use of pre-roasted nibs. Food Microbiology, 82, 99-106. doi:10.1016/j.fm.2019.01.009Quelal-Vásconez, M. A., Lerma-García, M. J., Pérez-Esteve, É., Arnau-Bonachera, A., Barat, J. M., & Talens, P. (2020). Changes in methylxanthines and flavanols during cocoa powder processing and their quantification by near-infrared spectroscopy. LWT, 117, 108598. doi:10.1016/j.lwt.2019.108598Quelal‐Vásconez, M. A., Lerma‐García, M. J., Pérez‐Esteve, É., Talens, P., & Barat, J. M. (2020). Roadmap of cocoa quality and authenticity control in the industry: A review of conventional and alternative methods. Comprehensive Reviews in Food Science and Food Safety, 19(2), 448-478. doi:10.1111/1541-4337.12522Razzaque, M. A., Saud, Z. A., Absar, N., Karim, M. R., & Hashinaga, F. (2000). Purification and Characterization of Polyphenoloxidase from Guava Infected with Fruit-rot Disease. Pakistan Journal of Biological Sciences, 3(3), 407-410. doi:10.3923/pjbs.2000.407.410Rimbach, G., Melchin, M., Moehring, J., & Wagner, A. (2009). Polyphenols from Cocoa and Vascular Health—A Critical Review. International Journal of Molecular Sciences, 10(10), 4290-4309. doi:10.3390/ijms10104290Rodríguez, P., Pérez, E., & Guzmán, R. (2009). Effect of the types and concentrations of alkali on the color of cocoa liquor. Journal of the Science of Food and Agriculture, 89(7), 1186-1194. doi:10.1002/jsfa.3573Saltini, R., Akkerman, R., & Frosch, S. (2013). Optimizing chocolate production through traceability: A review of the influence of farming practices on cocoa bean quality. Food Control, 29(1), 167-187. doi:10.1016/j.foodcont.2012.05.054Sarmadi, B., Aminuddin, F., Hamid, M., Saari, N., Abdul-Hamid, A., & Ismail, A. (2012). Hypoglycemic effects of cocoa (Theobroma cacao L.) autolysates. Food Chemistry, 134(2), 905-911. doi:10.1016/j.foodchem.2012.02.202Sarmadi, B., Ismail, A., & Hamid, M. (2011). Antioxidant and angiotensin converting enzyme (ACE) inhibitory activities of cocoa (Theobroma cacao L.) autolysates. Food Research International, 44(1), 290-296. doi:10.1016/j.foodres.2010.10.017Scalone, G. L. L., Textoris-Taube, K., De Meulenaer, B., De Kimpe, N., Wöstemeyer, J., & Voigt, J. (2019). Cocoa-specific flavor components and their peptide precursors. Food Research International, 123, 503-515. doi:10.1016/j.foodres.2019.05.019Schroder, T., Vanhanen, L., & Savage, G. P. (2011). Oxalate content in commercially produced cocoa and dark chocolate. Journal of Food Composition and Analysis, 24(7), 916-922. doi:10.1016/j.jfca.2011.03.008Shankar, M. U., Levitan, C. A., Prescott, J., & Spence, C. (2009). The Influence of Color and Label Information on Flavor Perception. Chemosensory Perception, 2(2), 53-58. doi:10.1007/s12078-009-9046-4Singh, P., Kesharwani, R. K., & Keservani, R. K. (2017). Antioxidants and Vitamins. Sustained Energy for Enhanced Human Functions and Activity, 385-407. doi:10.1016/b978-0-12-805413-0.00024-7Tanaka M. &Terauchi M.(1999).Cocoa powder rich in polyphenols process for producing the same and modified cocoa containing the same. US6485772B1.Taş, N. G., & Gökmen, V. (2016). Effect of alkalization on the Maillard reaction products formed in cocoa during roasting. Food Research International, 89, 930-936. doi:10.1016/j.foodres.2015.12.021Terink J. &Brandon M. J.(1981).Alkalized cocoa powders and foodstuffs containing such powders. US4435436A.Todorovic, V., Milenkovic, M., Vidovic, B., Todorovic, Z., & Sobajic, S. (2017). Correlation between Antimicrobial, Antioxidant Activity, and Polyphenols of Alkalized/Nonalkalized Cocoa Powders. Journal of Food Science, 82(4), 1020-1027. doi:10.1111/1750-3841.13672Tomas-Barberán, F. A., Cienfuegos-Jovellanos, E., Marín, A., Muguerza, B., Gil-Izquierdo, A., Cerdá, B., … Espín, J. C. (2007). A New Process To Develop a Cocoa Powder with Higher Flavonoid Monomer Content and Enhanced Bioavailability in Healthy Humans. Journal of Agricultural and Food Chemistry, 55(10), 3926-3935. doi:10.1021/jf070121jTotlani, V. M., & Peterson, D. G. (2005). Reactivity of Epicatechin in Aqueous Glycine and Glucose Maillard Reaction Models:  Quenching of C2, C3, and C4 Sugar Fragments. Journal of Agricultural and Food Chemistry, 53(10), 4130-4135. doi:10.1021/jf050044xTotlani, V. M., & Peterson, D. G. (2006). Influence of Epicatechin Reactions on the Mechanisms of Maillard Product Formation in Low Moisture Model Systems. Journal of Agricultural and Food Chemistry, 55(2), 414-420. doi:10.1021/jf0617521Trout R. B.(2001).Method for making dutched cocoa. EP1278428B1.Turcotte, A.-M., Scott, P. M., & Tague, B. (2013). Analysis of cocoa products for ochratoxin A and aflatoxins. Mycotoxin Research, 29(3), 193-201. doi:10.1007/s12550-013-0167-xWang, R., Wang, T., Zheng, Q., Hu, X., Zhang, Y., & Liao, X. (2012). Effects of high hydrostatic pressure on color of spinach purée and related properties. Journal of the Science of Food and Agriculture, 92(7), 1417-1423. doi:10.1002/jsfa.4719Wiant M. J. William R. Lynch W. R. &LeFreniere R. C.(1989).Method for producing deep red and black cocoa. US5009917A.Wissgott U.(1988).Process of alkalization of cocoa in aqueous phase. US4784866A.Wollgast, J., & Anklam, E. (2000). Review on polyphenols in Theobroma cacao: changes in composition during the manufacture of chocolate and methodology for identification and quantification. Food Research International, 33(6), 423-447. doi:10.1016/s0963-9969(00)00068-5Zhang, L., Xia, Y., & Peterson, D. G. (2014). Identification of Bitter Modulating Maillard-Catechin Reaction Products. Journal of Agricultural and Food Chemistry, 62(33), 8470-8477. doi:10.1021/jf502040eZhu, Q. Y., Holt, R. R., Lazarus, S. A., Ensunsa, J. L., Hammerstone, J. F., Schmitz, H. H., & Keen, C. L. (2002). Stability of the Flavan-3-ols Epicatechin and Catechin and Related Dimeric Procyanidins Derived from Cocoa. Journal of Agricultural and Food Chemistry, 50(6), 1700-1705. doi:10.1021/jf011228

    Testing the FMR1 Promoter for Mosaicism in DNA Methylation among CpG Sites, Strands, and Cells in FMR1-Expressing Males with Fragile X Syndrome

    Get PDF
    Variability among individuals in the severity of fragile X syndrome (FXS) is influenced by epigenetic methylation mosaicism, which may also be common in other complex disorders. The epigenetic signal of dense promoter DNA methylation is usually associated with gene silencing, as was initially reported for FMR1 alleles in individuals with FXS. A paradox arose when significant levels of FMR1 mRNA were reported for some males with FXS who had been reported to have predominately methylated alleles. We have used hairpin-bisufite PCR, validated with molecular batch-stamps and barcodes, to collect and assess double-stranded DNA methylation patterns from these previously studied males. These patterns enable us to distinguish among three possible forms of methylation mosaicism, any one of which could explain FMR1 expression in these males. Our data indicate that cryptic inter-cell mosaicism in DNA methylation can account for the presence of FMR1 mRNA in some individuals with FXS

    A pilot open label, single dose trial of fenobam in adults with fragile X syndrome

    Get PDF
    ObjectiveA pilot open label, single dose trial of fenobam, an mGluR5 antagonist, was conducted to provide an initial evaluation of safety and pharmacokinetics in adult males and females with fragile X syndrome (FXS).MethodsTwelve subjects, recruited from two fragile X clinics, received a single oral dose of 50-150 mg of fenobam. Blood for pharmacokinetic testing, vital signs and side effect screening was obtained at baseline and numerous time points for 6 h after dosing. Outcome measures included prepulse inhibition (PPI) and a continuous performance test (CPT) obtained before and after dosing to explore the effects of fenobam on core phenotypic measures of sensory gating, attention and inhibition.ResultsThere were no significant adverse reactions to fenobam administration. Pharmacokinetic analysis showed that fenobam concentrations were dose dependent but variable, with mean (SEM) peak values of 39.7 (18.4) ng/ml at 180 min after the 150 mg dose. PPI met a response criterion of an improvement of at least 20% over baseline in 6 of 12 individuals (4/6 males and 2/6 females). The CPT did not display improvement with treatment due to ceiling effects.ConclusionsClinically significant adverse effects were not identified in this study of single dose fenobam across the range of dosages utilised. The positive effects seen in animal models of FXS treated with fenobam or other mGluR5 antagonists, the apparent lack of clinically significant adverse effects, and the potential beneficial clinical effects seen in this pilot trial support further study of the compound in adults with FXS

    FMR1 premutation and full mutation molecular mechanisms related to autism

    Get PDF
    Fragile X syndrome (FXS) is caused by an expanded CGG repeat (>200 repeats) in the 5′ un-translated portion of the fragile X mental retardation 1 gene (FMR1) leading to a deficiency or absence of the FMR1 protein (FMRP). FMRP is an RNA-binding protein that regulates the translation of a number of other genes that are important for synaptic development and plasticity. Furthermore, many of these genes, when mutated, have been linked to autism in the general population, which may explain the high comorbidity that exists between FXS and autism spectrum disorders (ASD). Additionally, premutation repeat expansions (55 to 200 CGG repeats) may also give rise to ASD through a different molecular mechanism that involves a direct toxic effect of FMR1 mRNA. It is believed that RNA toxicity underlies much of the premutation-related involvement, including developmental concerns like autism, as well as neurodegenerative issues with aging such as the fragile X-associated tremor ataxia syndrome (FXTAS). RNA toxicity can also lead to mitochondrial dysfunction, which is common in older premutation carriers both with and without FXTAS. Many of the problems with cellular dysregulation in both premutation and full mutation neurons also parallel the cellular abnormalities that have been documented in idiopathic autism. Research regarding dysregulation of neurotransmitter systems caused by the lack of FMRP in FXS, including metabotropic glutamate receptor 1/5 (mGluR1/5) pathway and GABA pathways, has led to new targeted treatments for FXS. Preliminary evidence suggests that these new targeted treatments will also be beneficial in non-fragile X forms of autism

    Neural progenitor cells from an adult patient with fragile X syndrome

    Get PDF
    BACKGROUND: Currently, there is no adequate animal model to study the detailed molecular biochemistry of fragile X syndrome, the leading heritable form of mental impairment. In this study, we sought to establish the use of immature neural cells derived from adult tissues as a novel model of fragile X syndrome that could be used to more fully understand the pathology of this neurogenetic disease. METHODS: By modifying published methods for the harvest of neural progenitor cells from the post-mortem human brain, neural cells were successfully harvested and grown from post-mortem brain tissue of a 25-year-old adult male with fragile X syndrome, and from brain tissue of a patient with no neurological disease. RESULTS: The cultured fragile X cells displayed many of the characteristics of neural progenitor cells, including nestin and CD133 expression, as well as the biochemical hallmarks of fragile X syndrome, including CGG repeat expansion and a lack of FMRP expression. CONCLUSION: The successful production of neural cells from an individual with fragile X syndrome opens a new avenue for the scientific study of the molecular basis of this disorder, as well as an approach for studying the efficacy of new therapeutic agents
    corecore