Publications 2003 - 2009
Wilson S, Vennervald BJ, Kadzo H, Ireri E, Amaganga C, Booth M, Kariuki HC, Mwatha JK, Kimani G, Ouma JH, Muchiri E, Dunne DW. (2009) Health implications of chronic hepatosplenomegaly in Kenyan school-aged children chronically exposed to malarial infections and Schistosoma mansoni. Trans R Soc Trop Med Hyg 2009 Oct 7. [Epub ahead of print]
Fitzsimmons CM, Dunne DW. (2009) Survival of the fittest: allergology or parasitology? Trends Parasitol 25:447-51.
Schramm G, Hamilton JV, Balog CI, Wuhrer M, Gronow A, Beckmann S, Wippersteg V, Grevelding CG, Goldmann T, Weber E, Brattig NW, Deelder AM, Dunne DW, Hokke CH, Haas H, Doenhoff MJ. (2009) Molecular characterisation of kappa-5, a major antigenic glycoprotein from Schistosoma mansoni eggs. Mol Biochem Parasitol 166:4-14.
Tweyongyere R, Mawa PA, Emojong NO, Mpairwe H, Jones FM, Duong T, Dunne DW, Vennervald BJ, Katunguka-Rwakishaya E, Elliott AM. (2009) Effect of praziquantel treatment of Schistosoma mansoni during pregnancy on intensity of infection and antibody responses to schistosome antigens: results of a randomised, placebo-controlled trial. BMC Infect Dis 9:e32.
Zaccone P, Burton O, Miller N, Jones FM, Dunne DW, Cooke A. (2009) Schistosoma mansoni egg antigens induce Treg that participate in diabetes prevention in NOD mice. Eur J Immunol 39:1098-107.
Wilson S, Jones FM, Mwatha JK, Kimani G, Booth M, Kariuki HC, Vennervald BJ, Ouma JH, Muchiri E, Dunne DW. (2009) Hepatosplenomegaly associated with chronic malaria exposure: evidence for a pro-inflammatory mechanism exacerbated by schistosomiasis. Parasite Immunol 31:64-71.
Fitzpatrick JM,Fuentes JM, Chalmers IW, Wynn TA, Modolell M, Hoffmann KF, Hesse M. (2009) Schistosoma mansoni arginase shares functional similarities with human orthologs but depends upon disulphide bridges for enzymatic activity. Int J Parasitol 39:267-79.
Lockyer AE, Spinks J, Kane RA, Hoffmann KF, Fitzpatrick JM, Rollinson D, Noble LR, Jones CS. (2008) Biomphalaria glabrata transcriptome: cDNA microarray profiling identifies resistant- and susceptible-specific gene expression in haemocytes from snail strains exposed to Schistosoma mansoni. BMC Genomics 9:e634.
Fitzpatrick JM, Protasio AV, McArdle AJ, Williams GA, Johnston DA, Hoffmann KF. (2008) Use of Genomic DNA as an Indirect Reference for Identifying Gender-Associated Transcripts in Morphologically Identical, but Chromosomally Distinct, Schistosoma mansoni Cercariae. PLoS Negl Trop Dis 2:e323.
Hillier SD, Booth M, Muhangi L, Nkurunziza P, Khihembo M, Kakande M, Sewankambo M, Kizindo R, Kizza M, Muwanga M, Elliott AM. (2008) Plasmodium falciparum and helminth coinfection in a semi urban population of pregnant women in Uganda. J Infect Dis 198:920-7.
Wilson, S., Jones, FM., Mwatha, JK., Kimani, G., Booth, M., Kariuki, HC., Vennervald, BJ., Ouma, JH., Muchiri, E., Dunne, DW. (2008) Hepatosplenomegaly is associated with low regulatory and Th2 responses to schistosome antigens in childhood schistosomiasis and malaria coinfection.
Infect Immun. 76:2212-8. Abstract. Full Article
Reimert, CM., Tukahebwa, EM., Kabatereine, NB., Dunne, DW., Vennervald, BJ. (2008) Assessment of Schistosoma mansoni induced intestinal inflammation by means of eosinophil cationic protein, eosinophil protein X and myeloperoxidase before and after treatment with praziquantel. Acta Trop. 105:253-9. Abstract. Full Article
Chalmers, IW., AcArdle, AJ., Coulson, RM., Wagner, MA., Schmid, R., Hirai, H., Hoffmann, KF. (2008) Developmentally regulated expression, alternative splicing and distinct sub-groupings in members of the Schistosoma mansoni venom allergen-like (SmVAL) gene family. BMC Genomics 9:89. Abstract. Full Article
Aslam, A. Quinn, P. McIntosh, RS. Shi, J. Ghumra, A. McKerrow, JH., Bunting, K. Dunne, DW. Doenhoff, MJ., Morrison, SL. Zhang, K. Pleass, RJ. (2008) Proteases from Schistosoma mansoni cercariae cleave IgE at solvent exposed interdomain regions. Molecular Immunology 45:567-74. Abstract. Full Article
Fitzsimmons, CM., McBeath, R., Joseph, S., Jones, FM., Walter, K., Hoffmann, KF., Kariuki, HC., Mwatha, JK., Kimani, G., Kabatereine, NB., Vennervald, BJ., Ouma, JH., Dunne, DW. (2007) Factors affecting human IgE and IgG responses to allergen-like molecules from Schistosoma mansoni: molecular structure and patterns of in vivo exposure. Int Arch Allergy Immunol. 142:40-50. Abstract. Full Article
Vennervald, BJ., Dunne, DW. (2007) Measuring schistosomiasis morbidity. In: Report of the Scientific Working Group on Schistosomiasis, 2005, pp 57-61, TDR/SWG/07
Pinot de Moira, A., Fulford, AJ., Kabatereine, NB., Kazibwe, F., Ouma, J., Dunne, DW., Booth, M. (2007) Microgeographical and Ethnic Variations in Water Contact and Schistosoma mansoni exposure within a Ugandan Fishing Community. Trop Med Int Health. 12:724-35. Abstract. Full Article
Wilson, S. ,Booth, M., Jones, FM. , Mwatha, JK.. Kimani, G., Kariuki, HF., Vennervald, BJ., Ouma, JH., Muchiri, E,. Dunne, DW. (2007) Age-adjusted Plasmodium falciparum antibody levels in school-aged children are a stable marker of microgeographical variations in exposure to Plasmodium infection. BMC Infectious Diseases 7:67. Abstract. Full Article
Wilson, S., Vennervald, BJ., Kadzo, H., Ireri, E., Amaganga, C., Booth, M., Kariuki, HC., Mwatha, JK., Kimani, G., Ouma, JH., Muchuri, E., Dunne, DW. (2007)Hepatosplenomegaly in Kenyan schoolchildren: exacerbation by concurrent chronic exposure to malaria and Schistosoma mansoni infection. Trop Med Int Health 12:1442-9. Abstract. Full Article
Grevelding, CG., Hoffmann, KF. (2007) Schistosome genomics and beyond: news and views. Exp Parasitol. 11:223-4. Full Article
Hooke, CH., Deelder, AM., Hoffmann, KF., Wuhrer, M. (2007) Glycomics-driven discoveries in schistosome research.Exp Parasitol. 117:275-83. Abstract
Hokke, CH., Fitzpatrick, JM., Hoffmann, KF. (2007) Integrating transcriptome, proteome and glycome analyses of Schistosoma biology. Trends Parasitol. 23:165-74. Abstract. Full Article
Fitzpatrick, JM., Hirai, Y., Hirai, H., Hoffmann, KF. (2007) Schistosome egg production is dependent upon the activities of two developmentally regulated tyrosinases. FASEB J. 21:823-35. Abstract. Full Article
Dunne, DW. Vennervald, BJ. Booth, M. Joseph, S. Fitzsimmons, Cahen, P. Sturrock, R.F. Ouma, JH. Mwatha, JK. Kimani, G. Kariuki, HC. Kazibwe F, Tukahebwa E, Kabatereine NB. (2006). Applied and basic research on the epidemiology, morbidity, and immunology of schistosomiasis in fishing communities on Lake Albert Uganda. Trans R Soc Trop Med Hyg 100:216-223. Abstract
Wuhrer M, Balog CI, Catalina MI, Jones FM, Schramm G, Haas H, Doenhoff MJ, Dunne DW, Deelder AM, Hokke CH (2006) IPSE/alpha-1, a major secretory glycoprotein antigen from schistosome eggs, expresses the Lewis X motif on core-difucosylated N-glycans. FEBS J. 273:2276-92. Abstract
Fitzpatrick, JM., Hoffmann, KF. (2006) Dioecious Schistosoma mansoni express divergent gene repertoires regulated by pairing. Int J Parasitol. 36:1081-9. Abstract
Wuhrer, M., Koeleman, CA., Fitzpatrick, JM., Hoffmann, KF., Deelder, AM., Hokke, CH. (2006) Gender-specific expression of complex-type N-glycans in schistosomes.Glycobiology. 16:991-1006. Abstract
Vermeire, JJ., Taft, AS, Hoffmann, Fitzpatrick, JM., Yoshino, TP. (2006) Schistosoma mansoni: DNA microarray gene expression profiling during the miracidium-to-mother sporocyst transformation. Mol Biochem Parasitol. 147:39-47. Abstract
Booth, M. (2006) The role of residential location in apparent helminth and malaria associations.
Trends Parasitol. 22:359-62. Abstract
Reimert, CM., Fitzsimmons, CM., Joseph, S., Kimani, G., Mwatha, JK., Jones, FM., Hoffman, K., Booth, M., Kabatereine, NB., Dunne, DW., Vennervald, BJ. (2006) Eosinophil activity in Schistosoma mansoni infections in vivo and in vitro in relation to plasma cytokine profile pre- and post-treatment with praziquantel. Clin Vaccine Immunol. 13:584-593. Abstract
Brown, M., Miiro, G., Nkurunziza, P., Watera, C., Quigley, MA., Dunne, DW., Whitworth, JAG., Elliott, AM. (2006). Schistosoma mansoni, nematode infection and progression of active tuberculosis among HIV-1-infected Ugandans. Am J Trop Med Hyg. 74:819-825. Abstract
Booth, M., Shaw, M.A., Carpenter, D., Joseph, S., Kabatereine, N. B., Kariuiki, H.C., Mwatha, J. K., Jones,, F. M., Vennervald, B.J., Ouma, J.H., Dunne. DW. (2006). Carriage of DRB1*13 is associated with increased post-treatment IgE levels against Schistosoma mansoni antigens, and lower long-term re-infection levels. Journal of Immunology 176:7112-7118. Abstract
Pierrot, C., Wilson, S., Lallet, H., Lafitte, S., Jones, FM., Capron, M., Dunne, DW*., Khalife, J.* (2006). Identification of a novel antigen of Schistosoma mansoni shared with Plasmodium falciparum: different crossreactive antibody subclasses induced by human schistosomiasis and malaria Infection and Immunity. 74:3347-3354. (*joint last authors). Abstract
McIntosh, RS., Jones, FM., Dunne, DW., McKerrow, JH., Pleass, RJ. (2006) Chacterization of immunoglobulin binding by schistosomes Parasite Immunology. 28:407-419. Abstract
Paola Zaccone, Zoltan Fehervari, Jenny Phillips, David W. Dunne, and Anne Cooke (2006) Parasitic Worms and Inflammatory Diseases. Parasite Immunology 28:515-523. Abstract
Walter, K., Fulford, AJ., McBeath, R., Joseph, S., Jones, FM., Kariuki, CH., Mwatha, JK., Kimani, G., Sturrock, RF., Kabatereine, NB., Kemijumbi, J., Vennervald, BJ., Ouma, JH., Dunne, DW. (2006) Increased human IgE induced by killing Schistosoma mansoni in vivo is associated with pre-treatment Th-2 cytokine responsiveness to worm antigens. Journal of Immunology. 177:5490-8. Abstract
Fitzpatrick, JM., Johnson DA., Williams, GW., Williams, DJ, Freeman, TC. Dunne, DW., Hoffmann, KF. (2005) An oligonucleotide microarray for transcriptome analysis of Schistosoma mansoni and its application/use to investigate gender-associated gene expression. Mol Biochem Parasitol. 141:1-13. Abstract
Brown, M., Mawa, PA., Joseph, S., Bukusuba, J., Watera, C., Whitworth, JAG., Dunne, DW., Elliott, AM. (2005) Treatment of schistosomiasis increases helminth-specific type 2 cytokines and HIV-1 RNA levels in co-infected Ugandans. Journal of Infectious Diseases. 191:1648-57. Abstract
Dunne, DW and Cooke, A. (2005) A worm’s eye view of the immune system: consequences for evolution of human autoimmune disease. Nature Reviews in Immunology 5:8-15. Abstract
Fitzsimmons, CM., Gabriele Schramm, G., Jones, FM., Chalmers, IW., Hoffmann. KF., Grevelding, CG., Wuhrer, M., Hokke, CH., Haas, H., Doenhoff, MJ., Dunne, DW. (2005) Molecular characterization of omega-1; a hepatotoxic ribonuclease from Schistosoma mansoni eggs. Mol. Biochem. Parasitol. 144:123-127. Abstract
Dunne DW and Booth M. Immunological and other factors affecting hepatosplenic Schistosomiasis mansoni in man. In: Schistosomiasis (World Class Parasites), eds Secor WG and Colley DG (2005) Springer Verlag, Germany
Vennervald BJ, Booth M, Butterworth AE, Kariuki HC, Kadzo H, Ireri E, Amaganga C, Kimani G, Kenty L, Mwatha J, Ouma JH, Dunne DW (2005). Regression of hepatosplenomegaly in Kenyan school-aged children after praziquantel treatment and three years of greatly reduced exposure to Schistosoma mansoni. Trans R Soc Trop Med Hyg .Feb;99(2):150-60. Abstract
Booth M, Vennervald BJ, Butterworth AE, Kariuki HC, Amaganga C, Kimani G, Mwatha JK, Otedo A, Ouma JH, Dunne DW (2004). Exposure to malaria affects the regression of hepatosplenomegaly after treatment for Schistosoma mansoni infection in Kenyan children. BMC Med. Sep 27;2(1):36. Abstract
Fitzsimmons CM, Stewart TJ, Hoffmann KF, Grogan JL, Yazdanbakhsh M and Dunne DW (2004). Human IgE response to the Schistosoma haematobium 22.6 kDa antigen. Parasite ImmunolAug;26(8-9):371-6. Abstract
Raine T, Zaccone P, Dunne DW and Cooke A (2004). Can helminth antigens be exploited therapeutically to downregulate pathological Th1 responses? Curr Opin Investig Drugs Nov;5(11):1184-91. Abstract
Fitzpatrick JM, Johansen MV, Johnston DA, Dunne DW and Hoffmann KF. Gender-associated gene expression in two related strains of Schistosoma japonicum. Mol Biochem Parasitol. 2004 Aug;136(2):191-209. Abstract
Joseph, S., Jones, F.M., Laidlaw, M.E., Mohammed, G., Mawa, P.A., Namujji, P.B., Kizza, M., Watera, C., Whitworth, J.A.G., Dunne, D.W. and Elliot, A.M. Impairment of the Schistosoma mansoni -specific immune responses elicited by treatment with Praziquantel in Ugandans with HIV-1 coinfection. J. Infect. Dis. 190, 613-618, 2004. Abstract
Bogers JJ, Chatterjee S, Jacobs W, Fallon PG, Dunne DW, Langermans JA, Deelder AM, Thomas AW, Van Marck EA. Juvenile rhesus monkeys have more colonic granulomas than adults after primary infection with Schistosoma mansoni. Virchows Arch. 2004 Jul 30; [Epub ahead of print]
Cooke, A., Zaccone, P., Raine, T., Phillips, J.M. and Dunne, D.W. Infection and autoimmunity: are we winning the war, only to lose the peace? Trends in Parasitol. 20, 316-321, 2004. Abstract
Feng, C.G., Aliberti, J., Hoffmann, K.F., Jankovic, D., Kullberg, M.C., Sher, A. and Wynn, T.A. Experimental models for the analysis of IL-10 function. In: Interleukin-10, Chapter 2, ed. Marincola, F.M., Eurekah, pp.1-16, 2004.
Hoffmann, K.F. and Fitzpatrick, J.M. Gene expression studies using self-fabricated parasite cDNA microarrays. In: Molecular Biology, Vol. 270: Parasite Genomics Protocols, ed. Melville, S., Humana Press, Inc., NJ, USA, pp.219-236, 2004. Abstract
David, T., Thomas, C., Zaccone, P., Dunne, D.W. and Cooke, A. The impact of infection on the incidence of autoimmune disease. Curr. Top. Med. Chem. 4, 521-529, 2004. Abstract
Vennervald, B.J., Kenty, L., Butterworth, A.E., Kariuki, C.H., Kadzo, H., Ireri, E., Amaganga, C., Kimani, G., Mwatha, J.K., Booth, M. Ouma, J.H. and Dunne, D.W. Detailed clinical and ultrasound examination of children from a Schistosoma mansoni endemic area in Kenya: hepatosplenic disease in the absence of portal fibrosis. Trop. Med. Int. Health 9, 461-470, 2004. Abstract
Joseph, S., Jones, F.M., Kimani, G., Mwatha, J.K., Kamau, T., Kazibwe, F., Kemijumbi, J., Kabatereine, N.B., Booth, M., Kariuki, C., Ouma, J.H., Vennervald, B.J. and Dunne, D.W. Cytokine production in whole blood cultures from a fishing community in a highly Schistosomiasis mansoni-endemic area of Uganda: the differential effect of parasite worm and egg antigens. Infect Immun 72, 728-734, 2004. Abstract
Wynn, T.A., Hesse, M., Sandler, N.G., Kaviratne, M., Hoffmann, K.F., Chiaramonte, M.G., Reiman, R., Cheever, A.W., Sypek, J.P. and Mentink-Kane, M.M. P-selectin suppresses hepatic inflammation and fibrosis in mice by regulating interferon gamma and the IL-13 decoy receptor. Hepatology 39, 676-687, 2004. Abstract
Booth, M., Vennervald, B.J., Kenty, L., Butterworth, A.E., Karuki, H.C., Kadzo, H., Ireri, E., Amaganga, C., Kimani, G., Mwatha, J.K., Otedo, A., Ouma, J.H., Murchiri, E. and Dunne, D.W. Micro-geographical variation in exposure to Schistosoma mansoni and malaria, and exacerbation of splenomegaly in Kenyan school-aged children. BMC Infect. Dis. 4:13, 2004. Full Article
Satti, M., Cahen, P., Skov, P., Joseph, S., Jones, F.M., Kimani, G., Mwatha, J., Ouma, J.H., Kabatereine, N.B., Kazibwe, F. and Dunne, D.W. Changes in IgE- and antigen-dependent histamine-release in peripheral blood of Schistosoma mansoni-infected Ugandan fishermen after treatment with praziquantel. BMC Immunol. 5:6, 2004. Full Article
Booth, M, Vennervald, B.J.V, Kabatereine, N. B., Kazibwe, F., Ouma, J. H., Kariuki, C. H., Muchiri, E., Kadzo, H., Ireri, E., Kimani,G., Mwatha, J. K. and Dunne, D. W. Hepatosplenic morbidity in two neighbouring communities in Uganda with high levels of Schistosoma mansoni infection but very different durations of residence. Trans R. Soc. Trop. Med. Hyg. 98, 125-136 2004. Abstract
Booth, M., Mwatha, J.K., Joseph, S., Jones, F.M., Kadzo, H., Ireri, E., Kazibwe, F., Kemijumbi, J., Kariuki, C., Kimani, G., Ouma, J.H., Kabatereine, N.B., Vennervald, B.J. and Dunne, D.W. Periportal fibrosis in human Schistosoma mansoni infection is associated with low IL-10, low IFN-g, high TNF-a, or low RANTES, depending on age and gender. J. Immunol. 172, 1295-1303, 2004. Abstract
Vennervald, BJ., Dunne, DW. (2004) Morbidity in schistosomiasis: an update. Current Opinions in Infectious Diseases. 17:439-447. Abstract
Dunne, DW. Riley, EM. (2004) Morbidity, Immunity and Immunoepidemiology in Parasite Infections. Parasite Immunology, 26, 425–428. Abstract
Booth, M., Dunne, DW. (2004) Spatial awareness in immunoepidemiology. Parasite Immunology, 26; 499-507. Abstract
Hoffmann, KF., Fitzpatrick, JM. (2004) Gene expression studies using self-fabricated parasite cDNA microarrays. Methods Mol Biol. 270:219-36. Abstract
Dunne, DW. & Vennervald, BJ. (2003) Schistosomiasis. In: Oxford Textbook of Medicine Fourth Edition; Vol 1 pp830-7; Eds, Warrell, DA., Cox, TM. & Firth, JD. Oxford University Press.
Kabatereine, N.M., Kemijumbi, J., Ouma, J.H., Sturrock, R.F., Butterworth, A.E., Madsen, H., Ornbjerg, N., Dunne, D.W. and Vennervald, B.J. Efficacy and side effects of praziquantel treatment in a highly endemic Schistosoma mansoni focus at Lake Albert, Uganda. Trans. Roy. Soc. Trop. Med. Hyg. 97, 599-603, 2003. Abstract
Hoffmann K.F. and Dunne D.W. Characterization of the Schistosoma transcriptome opens up the world of helminth genomics. Genome Biol. 5, 203 Epub 2003. Abstract
Naus, C.W.A., Jones, F.M., Satti, M.Z., Joseph, S., Riley, E.M., Kimani, G., Mwatha, J.K., Kariuki, C.H., Ouma, J.H., Kabatereine, N.B., Vennervald, B.J. and Dunne, D.W. Serological responses among individuals in areas where both schistosomiasis and malaria are co-endemic: cross-reactivity between Schistosoma mansoni and Plasmodium falciparum. J. Infect. Dis. 187, 1272-1282, 2003. Abstract
Mwatha, J.K., Jones, F.M., Mohamed, G., Naus, C.W., Kenty, L., Riley, E., Kimani, G., Ouma, J.K. and Dunne, D.W. Associations between anti-Schistosoma mansoni and -Plasmodium falciparum antibody responses and hepatosplenomegaly in Kenyan schoolchildren. J. Infect Dis. 187, 1337-1341, 2003. Abstract
Naus, C., Booth, M., Jones, F., Kemijumbi, J., Vennervald, B.J., Kariuki, C., Ouma, J.H., Kabatereine, N.B. and Dunne, D.W. The relationship between age, sex, egg-count and specific antibody responses against S. mansoni antigens in a Ugandan fishing community. Trop. Med. Int. Health 8, 561-568, 2003. Abstract
Elliott, A.M., Mawa, P.A., Joseph, S., Namujju, P.B., Kizza, M., Nakiyingi, J.S., Watera, C., Dunne, D.W. and Whitworth, A.G. Associations between helminth infection and CD4+ T cell count, viral load and cytokine responses in HIV-1 infected Ugandan adults. Trans. Roy. Soc.Trop. Med. Hyg 97, 103-108, 2003. Abstract
Naus, C.W.A., van Remoortere, A., Ouma, J.H., Kimani, G., Dunne, D.W., Kamerling, J.P., Deelder, A.M. and Hokke, C.H. Specific antibody responses to 3 Schistosome related carbohydrate structures in recently exposed immigrants and established residents of a S. mansoni endemic area. Infect. Immun. 71, 5676-5681, 2003. Abstract
Zaccone, P., Fehervari, Z., Jones, F.M., Sidobre, S., Dunne, D.W. and Cooke, A. Schistosoma mansoni antigens modulate the activity of the innate immune response and prevent onset of Type 1 diabetes. Eur. J. Immunol. 33, 1439-1449, 2003. Abstract
Booth, M., Vounatsou, P., N'Goran, E.K., Tanner, M. and Utzinger, J. The influence of sampling effort and the performance of the Kato-Katz technique in diagnosing Schistosoma mansoni and hookworm co-infections in rural Cote d'Ivoire. Parasitology 127, 525-531,2003. Abstract
Mentink-Kane, M.M., Cheever, A.W., Thompson, R.W., Hari, D.M., Kabatereine, N.B., Vennervald, B.J., Ouma, J.H., Mwatha, J.K., Jones, F.M., Donaldson, D.D., Grusby, M.J., Dunne, D.W. and Wynn, T.A. IL-13 receptor (alpha) 2 survival downmodulates granulomatous prolongs host survival in schistosomiasis. Proc. Natl. Acad. Sci. USA December 2003. Abstract
Fallon, P.G., Gibbons, J., Vervenne, R.A., Richardson, E.J., Kiarie, S., Fulford, A.J.C., Sturrock, R.F., Coulson, P.S., Deelder, A.M., Langermans, J.A.M., Thomas, A.W. and Dunne, D.W. Juvenile rhesus monkeys have lower type 2 cytokine responses than adults following primary infection with Schistosoma mansoni. J. Infect. Dis. 187, 939-945, 2003. Abstract