407 research outputs found
Sample Preparation Assisted By Electric Fields: Fundamentals, Advances, Applications, And Trends [preparo De Amostras Assistido Por Campo Elétrico: Fundamentos, Avanços, Aplicações E Tendências]
No full textSample preparation is commonly considered a key step to achieve selective, sensitive, and reliable chemical analyses, particularly those involving complex matrices. Although the application of electric fields to improve the speed and efficiency of sample preparation methods has been proven, this approach is still considered to be state-of-the-art; hence, further development is necessary to improve future applications. This review describes the fundamentals, advances, applications, and perspectives of using electric fields to enhance sample preparation techniques such as liquid-liquid and solid-liquid extractions in conventional and microscale devices.38810931106Pawliszyn, J., (2012) Em Handbook of Solid Phase Microextraction, , Pawliszyn, J.ed. Elsevier: London cap. 1Queiroz, S.C.N., Collins, C.H., Jardim, I.C.S.F., (2001) Quim. Nova, 24, p. 68Caldas, S.S., Goncalves, F.F., Primel, E.G., Prestes, O.D., Martins, M.L., Zanella, R., (2011) Quim. Nova, 34, p. 1604Seidi, S., Yamini, Y., (2012) Cent. Eur. J. Chem., 10, p. 938De Castro, M.D.L., Priego-Capote, F., (2007) Talanta, 72, p. 321Smith, F.E., Arsenault, E.A., (1996) Talanta, 43, p. 1207Chen, Y., Guo, Z.P., Wang, X.Y., Qiu, C.G., (2008) J. Chromatogr. A, 1184, p. 191Morales-Cid, G., Cardenas, S., Simonet, B.M., Valcarcel, M., (2010) TrAC, Trends Anal. Chem., 29, p. 158Gjelstad, A., Pedersen-Bjergaard, S., (2013) Anal. Methods, 5, p. 4549Gjelstad, A., Pedersen-Bjergaard, S., (2014) Electrophoresis, 35, p. 2421Yamini, Y., Seidi, S., Rezazadeh, M., (2014) Anal. Chim. Acta, 814, p. 1Seidi, S., Yamini, Y., Rezazadeh, M., (2015) Talanta, 132, p. 339Joseph, N.R., Stadie, W.C., (1938) J. Biol. Chem., 125, p. 795Stichlmair, J., Schmidt, J., Proplesch, R., (1992) Chem. Eng. Sci., 47, p. 3015Pedersen-Bjergaard, S., Rasmussen, K.E., (2006) J. Chromatogr. A, 1109, p. 183Carasek, E., Merib, J., Anal. Chim. Acta, , no preloStrathmann, H., (2010) Desalination, 264, p. 268Okamoto, Y., Hayashi, K., Kawahara, Y., Kumamaru, T., (1993) Bull. Chem. Soc. Jpn., 66, p. 1664Steiner, F., Bohn, P., (2003) Chromatographia, 58, p. 59Buscher, B.A.P., Tjaden, U.R., Van Der Greef, J., (1997) J. Chromatogr. A, 788, p. 165Haddad, P.R., Laksana, S., Simons, R.G., (1993) J Chromatogr., 640, p. 135Chen, H.M., Stubbins, A., Hatcher, P.G., (2011) Limnol. Oceanogr.: Methods, 9, p. 582Josefsson, B.O., (1970) Anal. Chim. Acta, 52, p. 65Debets, A.J.J., Kok, W.T., Hupe, K.P., Brinkman, U.A.T., (1990) Chromato-graphia, 30, p. 361Okamoto, Y., Sakamoto, N., Yamamoto, M., Kumamaru, T., (1991) J. Chromatogr., 539, p. 221Debets, A.J.J., Hupe, K.P., Kok, W.T., Brinkman, U.A.T., (1992) J. Chro-matogr., 600, p. 163Groenewegen, M.G.M., Vandemerbel, N.C., Slobodnik, J., Lingeman, H., Brinkman, U.A.T., (1994) Analyst, 119, p. 1753Novic, M., Dovzan, A., Pihlar, B., Hudnik, V., (1995) J. Chromatogr. A, 704, p. 530Haddad, P.R., Laksana, S., (1994) J. Chromatogr. A, 671, p. 131Kamphorst, J.J., Tjaden, U.R., Van Der Heijden, R., DeGroot, J., Van Der Greef, J., Hankemeier, T., (2009) Electrophoresis, 30, p. 2284Buscher, B.A.P., Hofte, A.J.P., Tjaden, U.R., Van Der Greef, J., (1997) J. Chromatogr. A, 777, p. 51Buscher, B.A.P., Tjaden, U.R., Van Der Greef, J., (1997) J. Chromatogr. A, 764, p. 135Thi, K.O.D., Kuban, P., Kuban, P., Kiplagat, I.K., Bocek, P., (2011) Electro-phoresis, 32, p. 464Cox, J.A., Carlson, R., (1981) Anal. Chim. Acta, 130, p. 313Himata, K., Warner, C., Currie, D., Graves, Q., Diachenko, G., (2005) J. AOAC Int., 88, p. 794Chon, K., Lee, Y., Traber, J., Von Gunten, U., (2013) Water. Res., 47, p. 5381Zhu, A.B., Chen, B.Y., Zhang, L., Westerhoff, P., (2015) Anal. Chem., 87, p. 2353Seip, K.F., Faizi, M., Vergel, C., Gjelstad, A., Pedersen-Bjergaard, S., (2014) Anal. Bioanal. Chem., 406, p. 2151Huang, C., Seip, K.F., Gjelstad, A., Pedersen-Bjergaard, S., (2015) J. Pharma-ceut. Biomed., 348, p. 1127Petersen, N.J., Foss, S.T., Jensen, H., Hansen, S.H., Skonberg, C., Snakenborg, D., Kutter, J.P., Pedersen-Bjergaard, S., (2011) Anal. Chem., 83, p. 44Gjelstad, A., Rasmussen, K.E., Pedersen-Bjergaard, S., (2007) J. Chromatogr. A, 1174, p. 104Davarani, S.S.H., Pourahadi, A., Nojavan, S., Banitaba, M.H., Nasiri-Aghdam, M., (2012) Anal. Chim. Acta, 722, p. 55Fotouhi, L., Yamini, Y., Molaei, S., Seidi, S., (2011) J. Chromatogr. A, 1218, p. 8581Petersen, J.P., Asmussen, K.E., Bjergaard, S.P., Gjelstad, A., (2011) Anal. Sci., 27, p. 965Davarani, S.S.H., Morteza-Najarian, A., Nojavan, S., Pourahadi, A., Abbassi, M.B., (2013) J. Sep. Sci., 36, p. 736Payan, M.R., Lopez, M.A.B., Torres, R.F., Navarro, M.V., Mochon, M.C., (2011) Talanta, 85, p. 394Nojavan, S., Pourahadi, A., Davarani, S.S.H., Morteza-Najarian, A., Abbassi, M.B., (2012) Anal. Chim. Acta, 745, p. 45Strieglerova, L., Kuban, P., Bocek, P., (2011) J. Chromatogr. A, 1218, p. 6248Hasheminasab, K.S., Fakhari, A.R., (2013) Anal. Chim. Acta, 767, p. 75Balchen, M., Lund, H., Reubsaet, L., Pedersen-Bjergaard, S., (2012) Anal. Chim. Acta, 716, p. 16Huang, C., Gjelstad, A., Pedersen-Bjergaard, S., (2015) Anal. Chim. Acta, 853, p. 328Huang, C., Gjelstad, A., Pedersen-Bjergaard, S., (2015) J. Membr. Sci., 481, p. 115Liu, Y., Zhang, X., Guo, L., Zhang, Y., Li, Z., Wang, Z., Huang, M., Chu, Q., (2014) Talanta, 128, p. 386Safari, M., Nojavan, S., Davarani, S.S.H., Morteza-Najarian, A., (2013) Anal. Chim. Acta, 789, p. 58Jamt, R.E.G., Gjelstad, A., Eibak, L.E.E., Øiestad, E.L., Christophersen, A.S., Rasmussen, K.E., Pedersen-Bjergaard, S., (2012) J. Chromatogr. A, 1232, p. 27Hasheminasab, K.S., Fakhari, A.R., Shahsavani, A., Ahmar, H., (2013) J. Chromatogr. A, 1285, p. 1Balchen, M., Halvorsen, T.G., Reubsaet, L., Pedersen-Bjergaard, S., (2009) J. Chromatogr. A, 1216, p. 6900Davarani, S.S.H., Najarian, A.M., Nojavan, S., Tabatabaei, M.A., (2012) Anal. Chim. Acta, 725, p. 51Huang, C., Eibak, L.E.E., Gjelstad, A., Shen, X., Trones, R., Jensen, H., Pedersen-Bjergaard, S., (2014) J. Chromatogr. A, 1326, p. 7Hasheminasab, K.S., Fakhari, A.R., (2015) J. Chromatogr. A, 1378, p. 1Basheer, C., Lee, J., Pedersen-Bjergaard, S., Rasmussen, K.E., Lee, H.K., (2010) J. Chromatogr. A, 1217, p. 6661Eibak, L.E.E., Rasmussen, K.E., Øiestad, E.L., Pedersen-Bjergaard, S., Gjelstad, A., (2014) Anal. Chim. Acta, 828, p. 48Ramos-Payán, M., Fernández-Torres, R., Pérez-Bernal, J.L., Callejón-Mochón, M., Bello-López, M.Á., (2014) Anal. Chim. Acta, 849, p. 7Hidalgo, C.R., Ramos-Payán, M., Ocaña-González, J.A., Martín-Valero, M.J., Bello-López, M.Á., (2014) Anal. Bioanal. Chem., 407, p. 1519Hasheminasab, K.S., Fakhari, A.R., Koruni, M.H., (2014) J. Sep. Sci., 37, p. 85Sun, J.-N., Chen, J., Shi, Y.-P., (2014) J. Chromatogr. A, 1352, p. 1Rezazadeh, M., Yamini, Y., Seidi, S., Esrafli, A., (2012) J. Chromatogr. A, 1262, p. 214Rezazadeh, M., Yamini, Y., Seidi, S., Aghaei, A., (2015) Talanta, 136, p. 190Khajeh, M., Pedersen-Bjergaard, S., Barkhordar, A., Bohlooli, M., (2015) Spectrochim. Acta, Part A, 137, p. 328Asl, Y.A., Yamini, Y., Rezazadeh, M., Seidi, S., (2015) Anal. Methods, 7, p. 197Šlampová, A., Kubán, P., Bocek, P., (2014) Electrophoresis, 35, p. 3317Šlampová, A., Kubán, P., Bocek, P., (2014) Electrophoresis, 35, p. 2429Yamini, Y., Pourali, A., Seidi, S., Rezazadeh, M., (2014) Anal. Methods, 6, p. 5554Arjomandi-Behzad, L., Yamini, Y., Rezazadeh, M., (2014) Talanta, 126, p. 73Seip, K.F., Jensen, H., Kieu, T.E., Gjelstad, A., Pedersen-Bjergaard, S., (2014) J. Chromatogr. A, 1347, p. 1Ahmar, H., Tabani, H., Hossein Koruni, M., Davarani, S.S.H., Fakhari, A.R., (2014) Biosens. Bioelectron., 54, p. 189Fakhari, A.R., Koruni, M.H., Ahmar, H., Shahsavani, A., Movahed, S.K., (2014) Electroanalysis, 26, p. 521Dugstad, H.B., Petersen, N.J., Jensen, H., Gabel-Jensen, C., Honoré Hansen, S., Pedersen-Bjergaard, S., (2014) Anal. Bioanal. Chem., 406, p. 421Eibak, L.E.E., Parmer, M.P., Rasmussen, K.E., Pedersen-Bjergaard, S., Gjelstad, A., (2014) Anal. Bioanal. Chem., 406, p. 431Marando, M.A., Clark, W.M., (1993) Sep. Sci. Technol., 28, p. 1561Clark, W.M., (1992) CHEMTECH, 22, p. 425Bailes, P.J., (1981) Ind. Eng. Chem. Process Des. Dev., 20, p. 564Austin, L.J., Banczyk, L., Sawistowski, H., (1971) Chem. Eng. Sci., 26, p. 2120Hahn, T., Münchow, G., Hardt, S., (2011) J. Phys.: Condens. Matter, 23, p. 279502He, W., Bazrd, M.H.I., (1993) Can. J. Chem. Eng., 71, p. 366Luo, G.S., Jiang, W.B., Lu, Y.C., Zhu, S.L., Dai, Y.Y., (1999) Chem. Eng. J., 73, p. 137Pan, S., Luo, G.S., Liu, J.G., Wang, J.D., (2003) Sep. Sci. Technol., 38, p. 3731Zhai, S.L., Luo, G.S., Liu, J.G., (2001) Chem. Eng. J., 83, p. 55Campos, C.D.M., Park, J.K., Neuzil, P., Da Silva, J.A.F., Manz, A., (2014) Rsc. Adv., 4, p. 49485Willauer, H.D., Huddleston, J.G., Rogers, R.D., (2002) Ind. Eng. Chem. Res., 41, p. 1892Rosa, P.A.J., Ferreira, I.F., Azevedo, A.M., Aires-Barros, M.R., (2010) J. Chromatogr. A, 1217, p. 2296Xie, X., Wang, Y., Han, J., Yan, Y., (2011) Anal. Chim. Acta, 687, p. 61Simeone, M., Alfani, A., Guido, S., (2004) Food Hydrocolloids, 18, p. 463Babu, B.R., Rastogi, N.K., Raghavarao, K.S.M.S., (2008) Chem. Eng. Process., 47, p. 83Zhai, S.L., Luo, G.S., Liu, J.G., (2001) Sep. Purif. Technol., 21, p. 197Münchow, G., Hardt, S., Kutter, J.P., Drese, K.S., (2007) Lab Chip, 7, p. 98Ferreira, L., Madeira, P.P., Mikheeva, L., Uversky, V.N., Zaslavsky, B., (2013) Biochim. Biophys. Acta, 1834, p. 2859Weatherley, L.R., (1993) Heat Recovery Syst. CHP, 13, p. 515Scott, T.C., Wham, R.M., (1989) Ind. Eng. Chem. Res., 28, p. 94Glitzenstein, A., Tamir, A., Oren, Y., (1995) Can. J. Chem. Eng., 73, p. 95Theos, C.W., Clark, W.M., (1995) Appl. Biochem. Biotechnol., 54, p. 143Van Der Vlis, E., Mazereeuw, M., Tjaden, U.R., Irth, H., Van Der Greef, J., (1994) J. Chromatogr. A, 687, p. 333Van Der Vlis, E., Mazereeuw, M., Tjaden, U.R., Irth, H., Van Der Greef, J., (1995) J. Chromatogr. A, 712, p. 227Van Der Vlis, E., Mazereeuw, M., Tjaden, U.R., Irth, H., Van Der Greef, J., (1996) J. Chromatogr. A, 741, p. 13Lindenburg, P.W., Seitzinger, R., Tempels, F.W.A., Tjaden, U.R., Van Der Greef, J., Hankemeier, T., (2010) Electrophoresis, 31, p. 3903Lindenburg, P.W., Tjaden, U.R., Van Der Greef, J., Hankemeier, T., (2012) Electrophoresis, 33, p. 2987Lindenburg, P.W., Ramautar, R., Hankemeier, T., (2013) Bioanalysis, 5, p. 2785Lindenburg, P.W., Tempels, F.W.A., Tjaden, U.R., Van Der Greef, J., Hankemeier, T., (2012) J. Chromatogr. A, 1249, p. 17Lanças, F.M., (2004) Extração em Fase Sólida (SPE), , RiMa: São CarlosOrlando, R.M., (2011), Tese de Doutorado, Universidade Estadual de Campinas, BrasilOrlando, R.M., Rath, S., Rohwedder, J.J.R., (2013) Talanta, 116, p. 39Orlando, R.M., Rohwedder, J.J.R., Rath, S., (2014) Chromatographia, 77, p. 133Tavares, M.F.M., (1996) Quim. Nova, 19, p. 173Nischang, I., Spannmann, K., Tallarek, U., (2006) Anal. Chem., 78, p. 3601Snyder, L.R., Kirkland, J.J., Glajch, J.L., (1997) Practical HPLC Method Development2nd Ed, , Wiley: New YorkOrlando, R.M., Rath, S., (2007), Br PI 0703755-4Morales-Cid, G., Simonet, B.M., Cardenas, S., Valcarcel, M., (2008) Electrophoresis, 29, p. 2033Ribeiro, C.C., (2014), Tese de Doutorado, Universidade Estadual de Campinas, BrasilOrlando, R.M., Maniero, L., Rath, S., (2014), Br PI 102014 024585-5Manz, A., Graber, N., Widmer, H.M., (1990) Sens. Actuators B, 1, p. 244Whitesides, G.M., (2006) Nature, 442, p. 368Whitesides, G.M., (2011) Lab Chip, 11, p. 191Tabeling, P., (2014) Curr. Opin. Biotechnol., 25, p. 129Sinton, D., (2014) Lab Chip, 14, p. 3127Temiz, Y., Lovchik, R.D., Kaigala, G.V., Delamarche, E., (2015) Microelectron. Eng., 132, p. 156Rios, A., Zougagh, M., Avila, M., (2012) Anal. Chim. Acta, 740, p. 1Rios, A., Zougagh, M., (2013) TrAC, Trends Anal. Chem., 43, p. 174Coltro, W.K.T., Cheng, C.M., Carrilho, E., De Jesus, D.P., (2014) Electrophoresis, 35, p. 2309Coltro, W.K.T., Piccin, E., Carrilho, E., De Jesus, D.P., Da Silva, F., Torres da Silva, H.D., Do Lago, C.L., (2007) Quim. Nova, 30, p. 1986Tabeling, P., (2005) Introduction to Microfuidics, , Oxford Press: New YorkOleschuk, R.D., Shultz-Lockyear, L.L., Ning, Y., Harrison, D.J., (2000) Anal. Chem., 72, p. 585Kim, Y., Cha, M., Choi, Y., Joo, H., Lee, J., (2013) Chem. Phys. Lett., 561, p. 63Ren, K.N., Zhou, J.H., Wu, H.K., (2013) Acc. Chem. Res., 46, p. 2396Becker, H., Gartner, C., (2008) Anal. Bioanal. Chem., 390, p. 89Lee, J.N., Park, C., Whitesides, G.M., (2003) Anal. Chem., 75, p. 6544Ramsey, J.D., Collins, G.E., (2005) Anal. Chem., 77, p. 6664Kutter, J.R.P., Jacobson, S.C., Ramsey, J.M., (2000) J. Microcolumn Sep., 12, p. 93Hahn, T., Münchow, G., Hardt, S., (2011) J. Phys. Condens. Matter, 23, p. 184107Hahn, T., Hardt, S., (2011) Soft Matter, 7, p. 6320Hardt, S., Hahn, T., (2012) Lab Chip, 12, p. 434Kerby, M.B., Spaid, M., Wu, S., Parce, J.W., Chien, R.-L., (2002) Anal. Chem., 74, p. 5175Shin, D.H., Kim, J.-E., Shim, H.C., Song, J.-W., Yoon, J.-H., Kim, J., Jeong, S., Han, C.-S., (2008), 8, p. 4380. , Nano LettMünchow, G., Hardt, S., Kutter, J.P., Drese, K.S., (2006) JALA, 11, p. 368Schoonen, J.W., Van Duinen, V., Oedit, A., Vulto, P., Hankemeier, T., Lindenburg, P.W., (2014) Anal. Chem., 86, p. 8048Kubán, P., Bocek, P., (2012) J. Chromatogr. A, 1234, p. 2Petersen, N.J., Jensen, H., Hansen, S.H., Foss, S.T., Snakenborg, D., Pedersen-Bjergaard, S., (2010) Microfuid. Nanofuid., 9, p. 881Petersen, N.J., Foss, S.T., Jensen, H., Hansen, S.H., Skonberg, C., Snakenborg, D., Kutter, J.P., Pedersen-Bjergaard, S., (2011) Anal. Chem., 83, p. 44Petersen, N.J., Pedersen, J.S., Poulsen, N.N., Jensen, H., Skonberg, C., Hansen, S.H., Pedersen-Bjergaard, S., (2012) Analyst, 137, p. 3321Seidi, S., Rezazadeh, M., Yamini, Y., Zamani, N., Esmaili, S., (2014) Analyst, 139, p. 553
Assoziation der ACE-Aktivität und Polymorphismen und Hypoglykämieprobleme
No full textHypoglykämien stellen in der Behandlung des Typ 1-Diabetes Mellitus ein zentrales Problem dar. Mit dem Ziel, eine möglichst physiologische Insulinsubstitution zu erreichen, um diabetische Folgeschäden zu vermeiden, steigt auch die Gefahr von Hypoglykämien deutlich an. Werden diese Hypoglykämien von den Typ-1-Diabetikern als solche erkannt, können sie durch Kohlenhydratzufuhr sehr einfach behandelt werden. Problematischer ist es, wenn die Unterzuckerung asymptomatisch bleibt und in schweren Fällen bis zum Krampfanfall oder zur Bewusstlosigkeit führt. Dies stellt eine hohe psychische Belastung für die Betroffenen und deren Umfeld dar. Man weiss, dass mit steigender Erkrankungsdauer auch die Wahrscheinlichkeit steigt, eine Hypoglykämiewahrnehmungsstörung zu entwickeln. Jedoch scheinen nicht alle Typ-1-Diabetiker im Laufe ihrer Erkrankung eine Hypoglykämiewahrnehmungsstörung zu entwickeln, so dass hier von einer zusätzlichen genetischen Genese dieses Krankheitsbildes ausgegangen werden kann. Hierzu untersuchte die dänische Arbeitsgruppe um Pedersen-Bjergaard 171 Typ-1-Diabetiker hinsichtlich ihrer Hypoglykämiewahrnehmung und der Enzymaktivität beziehungsweise dem Genpolymorphismus des Angiotensin-Converting-Enzyms (ACE). Es wurde festgestellt, dass Typ-1-Diabetiker mit einer hohen Enzymaktivität, beziehungsweise dem Genpolymorphismus D/D (Deletionsallel) des ACE, ein 2.5-fach höheres Risiko haben eine Hypoglykämiewahrnehmungsstörung zu entwickeln als Typ-1-Diabetiker mit einer niedrigen Enzymaktivität beziehungsweise dem Genpolymorphismus I/I (Insertionsallel) des ACE. Sollten sich diese Daten in weiteren Studien bestätigen, könnte man mittels relativ einfacher Blutuntersuchung Voraussagen treffen, ob ein Typ-1-Diabetiker im Laufe der Erkrankung eine Hypoglykämiewahrnehmungsstörung entwickeln wird oder nicht. Dies hätte direkten Einfluss auf die individuelle Behandlungsstrategie. Diese mittels Fragebogen und Blutentnahme (zur Enzymbestimmung) erhobenen Daten wollten wir in dieser Studie experimentell verifizieren. Wir verwendeten die in der Hypoglykämieforschung etablierte hypoglykämische Glukose-Clamp-Technik. 26 Typ-1-Diabetiker wurden mittels experimentell induzierter und kontrollierter Hypoglykämie hinsichtlich ihrer Hypoglykämiewahrnehmung auf endokriner, symptomatischer und neuropsychologischer Ebene untersucht. Dazu wuden die jeweiligen Blutglukose-Spiegel mittels intravenös appliziertem Insulin auf 90 mg/dl (Euglykämie), 60 mg/dl (milde Hypoglykämie) und 45 mg/dl (moderate Hypoglykämie) stabilisiert, um auf diesen Blutglukose-Niveaus Blutbestimmungen vorzunehmen, Symptome abzufragen und Reaktionstests durchzuführen. Die Enzymaktivitäten des ACE sowie der jeweilige Genpolymorphismus dieses Enzyms wurden aus venösem Vollblut bestimmt. Es wurden zwei Gruppen mit je 13 Probanden mit hoher versus niedriger ACE-Aktivität am Median der absoluten Enzymaktivität des Angiotensin-Converting-Enzyms gebildet. Die Auswertung unserer Daten zeigte eine qualitativ gut durchgeführte Untersuchung, die angestrebten Blutzuckerspiegel wurden erreicht und alle Probanden haben die geforderten Tests beziehungsweise Fragebögen absolviert. Es zeigte sich kein signifikanter Unterschied der Typ-1-Diabetiker mit einer hohen ACE-Aktivität hinsichtlich ihrer Hypoglykämiewahrnehmung auf endokriner, symptomatischer und neuropsychologischer Ebene gegenüber der Vergleichsgruppe mit niedriger ACE-Aktivität. Die von Pedersen-Bjergaard veröffentlichten Daten konnten in dieser Arbeit experimentell nicht nachgewiesen werden. Es ist allerdings zu bedenken dass die von Pedersen-Bjergaard publizierten Arbeiten anhand retrospektiv ermittelter Daten entstanden sind, wohingegen in dieser vorgelegten Arbeit die Daten in einer experimentellen klinischen Studie erhoben worden sind. Als entscheidenden Nachteil dieser Arbeit darf man das geringe Probandenkollektiv sehen, was die statistische Aussagekraft verringert. Weitere klinische Studien mit einer größeren Anzahl an Probanden sollten folgen, um nach genetischen Ursachen für die Entstehung einer Hypoglykämiewahrnehmungsstörung zu suchen.Hypoglycaemia is one of the main problems in the treatment of type 1 diabetic patients. In the aim to reach a physiological insulin-substitution to reduce the long-term complications of diabetes, the risk of hypoglycaemic episodes will increase. It is easy to treat hypoglycaemia with eating carbohydrates if the episode is recognised as such as hypoglycaemia. It is much more complicated if the hypoglycaemia is asymptomatic and will result in epileptic seizure or unconsciousness. This is a great emotional stress for diabetic patients and their surroundings. It is known that the probability of hypoglycaemia unawareness increases with diabetes-duration. But not all type 1 diabetic patients develop this hypoglycaemia unawareness, so that genetic influence is suggested. The Danish team of Pedersen-Bjergaard investigated 171 type 1 diabetic patients in regard to their hypoglycaemia awareness and the activity and genotype of angiotensin converting enzyme (ACE). There was a positive relationship between serum-ACE-activity and rate of severe hypoglycaemia with a 2.7 times higher rate in patients with high enzyme-activity respectively genotype D/D (deletion allele) in comparison to patients with low activity of ACE respectively genotype I/I (insertion allele). If these results could be reproduced in other studies, it would be easy to predict the individual risk of hypoglycaemia unawareness. This could influence the individual management of insulin therapy. We tried to reproduce these results, which were recorded by questionnaires and blood sample (for enzyme diagnostic), in a clinical experimental trial. We used the glucose-clamp-technique, which is well established in hypoglycaemia research. By experimental induced hypoglycaemia, 26 type 1 diabetic patients were investigated in regard to their hypoglycaemia awareness on endocrine, symptomatic and neuropsychological level. To take blood samples, ask symptoms of hypoglycaemia and make reaction-tests, the blood-glucose-level of the participants were stabilised at 90 mg/dl (euglyceamia), 60 mg/dl (mild hypoglycaemia) and 45 mg/dl (moderate hypoglycaemia) by intravenous insulin infusion. We analysed the enzyme-activity of ACE and the genotype of this enzyme by venous blood samples. Two groups with 13 test persons, high versus low ACE-activity; each was build at the median range of absolute enzyme-activity of the angiotensine-converting-enzyme. The data-analyse showed a good quality of this study. All participants completed the required tests respectively questionnaires and the target values of blood glucose has been achieved. There was no significant difference between the two groups in regard to their hypoglycaemia awareness on endocrine, symptomatic and neuropsychological level. The data published by Pedersen-Bjergaard can not be proved by experimental way in this study. However it has to be considered that the data presented by Pedersen-Bjergaard developed from retrospective studies, whereas in this presented study data were collected by the way of clinical experimental study. The important handicap of this work is the small collective of test persons, which reduces the statistical power significant. Further clinical investigations with a larger number of patients should follow to search for genetic causes of hypoglycaemia unawareness in type 1 diabetic patients
A comparative evaluation of analytical green metrics for microextraction techniques based on polymeric and gel membranes as solid support
No full textSample preparation plays a pivotal role in chemical analysis, serving to isolate target analytes from diverse matrices and enhance measurement selectivity and sensitivity. This review examines microextraction's eco-friendliness versus tradition, focusing on LPME and EME systems for acidic compounds. Different solid supports (polymeric and gel membranes) implemented in different configurations are evaluated. These innovative techniques reduce the consumption of chemicals and offer enhanced environmental safety. To determine the greenness of these techniques, we employ three widely recognized metrics: Analytical Eco-Scale, Green Analytical Procedure Index (GAPI), and Analytical GREEnness (AGREE). Our comparative analysis provides insights into the strengths and weaknesses of these metrics and offers a holistic perspective on the greenness of microextraction techniques. This review contributes to the ongoing efforts in Green Analytical Chemistry by facilitating the selection of environmentally benign sample preparation methods, thus promoting sustainable laboratory practices, and minimizing adverse environmental impacts.Ministerio de Ciencia e Innovación de España (MCIN) - I+D+i PID2021-123073NB-C2
Electromembrane extraction–Recent trends and where to go
No full textElectromembrane extraction (EME) is an analytical microextraction technique, where charged analytes (such as drug substances) are extracted from an aqueous sample (such as a biological fluid), through a supported liquid membrane (SLM) comprising a water immiscible organic solvent, and into an aqueous acceptor solution. The driving force for the extraction is an electrical potential (dc) applied across the SLM. In this paper, EME is reviewed. First, the principle for EME is explained with focus on extraction of cationic and anionic analytes, and typical performance data are presented. Second, papers published in 2016 are reviewed and discussed with focus on (a) new SLMs, (b) new support materials for the SLM, (c) new sample additives improving extraction, (d) new technical configurations, (e) improved theoretical understanding, and (f) pharmaceutical new applications. Finally, important future research objectives and directions are defined for further development of EME, with the aim of establishing EME in the toolbox of future analytical laboratories
Impact of Nocturnal Hypoglycemia on Daily Sleep Quality, Mood, and Alertness among Adults with Type 1 Diabetes: The HypoMETRICS (Hypoglycaemia Measurement, Thresholds, and Impacts) Study
No full textAim: To examine how hypoglycemia while asleep impacts self-reported daily functioning among adults with type 1 diabetes (T1D) .
Methods: On 70 consecutive mornings, 250 people with T1D wearing a continuous glucose monitor reported sleep quality, mood, and alertness via the Hypo-METRICS smartphone app. Each night was categorized based on presence (+) or absence (-) of person-reported hypoglycemia (PRH) and sensor-detected hypoglycemia (SDH) into one of four types (see Figure 1, Type A-D) . Multilevel regression assessed associations between hypoglycemia and daily functioning (unstandardized coefficients (β) on original 0-scale) , adjusted for baseline demographic, clinical and psychological factors.
Results: In the first 54 adults (52% women, age[M±SD]: 45±15 years) , nighttime PRH (Type C & D, Figure 1) was associated with reduced subjective sleep quality (C: β=-0.67; D: β=-0.58) , mood (C: β=-0.43; D: β=-0.58) and alertness (C: β=-0.34, p=0.015; D: β=-0.46) (all p0.05) .
Conclusion: These novel data show the potentially pivotal role of the subjective experience of hypoglycemia for sleep quality, mood and alertness.
Disclosure
U.Soeholm: Research Support; Novo Nordisk A/S. E.Renard: Consultant; Abbott, AstraZeneca, Boehringer Ingelheim International GmbH, Dexcom, Inc., Insulet Corporation, LifeScan, Lilly, Novo Nordisk, Roche Diabetes Care, Sanofi, Tandem Diabetes Care, Inc. E.J.Abbink: None. P.M.Baumann: None. S.R.Heller: Advisory Panel; Eli Lilly and Company, Medtronic, Mylan N.V., Zealand Pharma A/S, Zucara Therapeutics, Other Relationship; Eli Lilly and Company, Research Support; Dexcom, Inc., Speaker's Bureau; Novo Nordisk A/S. B.E.De galan: Research Support; Novo Nordisk. U.Pedersen-bjergaard: Advisory Panel; Novo Nordisk A/S, Sanofi. M.Evans: Advisory Panel; Pila Pharma, Zucara Therapeutics, Other Relationship; Abbott Diabetes, Dexcom, Inc., Medtronic, Novo Nordisk, Research Support; AstraZeneca, Sanofi, Speaker's Bureau; Lilly Diabetes. D.Pollard: Other Relationship; Novo Nordisk. R.J.Mccrimmon: Advisory Panel; Novo Nordisk, Sanofi, Research Support; Diabetes UK, European Union, MedImmune. S.A.Amiel: Advisory Panel; Medtronic, Novo Nordisk, Other Relationship; Sanofi. M.M.Broadley: None. C.Hendrieckx: None. J.Speight: Advisory Panel; Insulet Corporation, Research Support; Novo Nordisk, Sanofi. P.Choudhary: Advisory Panel; Abbott Diabetes, Lilly Diabetes, Medtronic, Research Support; Novo Nordisk, Speaker's Bureau; Dexcom, Inc., Glooko, Inc., Insulet Corporation, Sanofi. F.Pouwer: Research Support; Eli Lilly and Company, Novo Nordisk, Sanofi. N.Zaremba: None. P.Divilly: None. G.Martine-edith: Other Relationship; Novo Nordisk. G.Nefs: None. Z.Mahmoudi: Employee; Novo Nordisk A/S. J.K.Mader: Advisory Panel; Abbott Diabetes, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Medtronic, Merck Sharp & Dohme Corp., Novo Nordisk A/S, Roche Diabetes Care, Sanofi-Aventis Deutschland GmbH, Speaker's Bureau; Abbott Diabetes, Eli Lilly and Company, Medtronic, Merck Sharp & Dohme Corp., Novo Nordisk A/S, Roche Diabetes Care, Sanofi-Aventis Deutschland GmbH, Servier Laboratories, Stock/Shareholder; decide Clinical Software GmbH. M.Cigler: None.
Funding
This work was supported by the Innovative Medicines Initiative 2 Joint Undertaking (JU) under grant agreement 77746
Recovery, enrichment and selectivity in liquid-phase microextraction:Comparison with conventional liquid-liquid extraction
No full textMathematical descriptions for extraction recovery and enrichment were applied for liquid-phase microextraction (LPME) and comparison with conventional two- and three-phase liquid-liquid extraction techniques (LLE) was made. The LPME theoretical calculations were verified by experimental determination of actual partition coefficients and by data obtained with LPME in a robust hollow fibre formate. With hollow fibre LPME operated in the two-phase mode, analytes were extracted from 1 to 4 ml aqueous samples into 25-50 μl of an organic solvent present in the pores and in the lumen of the porous hollow fibres. Compared with conventional two-phase LLE, two-phase LPME provided substantially higher enrichments for compounds with relatively large partition coefficients (Korg/d>500). In contrast, because of the large volume of organic solvent relative to the sample volume, LLE provided high recovery and moderate enrichment even for compounds with relatively low partition coefficients (Korg/d>5). Thus, two-phase LPME may be used for substantially enhanced extraction selectivity and enrichment of relatively hydrophobic analytes as compared with LLE whereas conventional two-phase LLE is superior for more hydrophilic analytes. Similar results were found for three-phase LPME where analytes where extracted from 1 to 4 ml aqueous samples through approximately 20 μl organic solvent immobilized within the pores of the hollow fibre and into 25 μl of an aqueous acceptor solution inside the lumen of the hollow fibre. The fundamental differences of LPME and LLE were further demonstrated with practical experiments on extraction of the basic drugs promethazine, methadone, and haloperidol from human plasma and urine.</p
ACE genotype, phenotype and all-cause mortality in different cohorts of patients with type 1 diabetes
No full textAIMS: Carrying the D-allele of the angiotensin-converting enzyme (ACE) I/D polymorphism and high ACE activity are prognostic factors in diabetic nephropathy, which predicts mortality in type 1 diabetes. We studied the association between the ACE D-allele and ACE phenotype and long-term all-cause mortality in three single-institution outpatient cohorts.METHODS: Genotype-based analyses were performed in 269 patients from Hillerød Hospital (HIH) (follow-up: 12 years) and in 439 patients with diabetic nephropathy and 437 patients with persistent normoalbuminuria from the Steno Diabetes Center (SDC) (follow-up: 9.5 years). Patients not on renin-angiotensin system (RAS)-blocking treatment were included in analyses of serum ACE activity (HIH: n = 208) and plasma ACE concentration (SDC: n=269).RESULTS: In the HIH cohort, carrying a D-allele was associated with excess mortality (hazard ratio (HR) = 4.0 (95% confidence interval (CI) 1.0-16)), but not in the SDC cohorts. At HIH, serum ACE activity was associated with excess mortality (HR=1.04 (95% CI 1.0-1.1 per unit increase)), but in the SDC cohort plasma ACE concentration was not.CONCLUSION: In unselected patients with type 1 diabetes, carrying the ACE D-allele and high spontaneous serum ACE activity were associated with 12-year excess mortality. These findings could not be reproduced in two other cohorts with persistent normoalbuminuria or diabetic nephropathy.</p
Acute hypoglycemia impairs executive cognitive function in adults with and without type 1 diabetes
No full textOBJECTIVE Acute hypoglycemia impairs cognitive function in several domains. Executive cognitive function governs organization of thoughts, prioritization of tasks, and time management. This study examined the effect of acute hypoglycemia on executive function in adults with and without diabetes.RESEARCH DESIGN AND METHODS Thirty-two adults with and without type 1 diabetes with no vascular complications or impaired awareness of hypoglycemia were studied. Two hyperinsulinemic glucose clamps were performed at least 2 weeks apart in a single-blind, counterbalanced order, maintaining blood glucose at 4.5 mmol/L (euglycemia) or 2.5 mmol/L (hypoglycemia). Executive functions were assessed with a validated test suite (Delis-Kaplan Executive Function). A general linear model (repeated-measures ANOVA) was used. Glycemic condition (euglycemia or hypoglycemia) was the within-participant factor. Between-participant factors were order of session (euglycemia-hypoglycemia or hypoglycemia-euglycemia), test battery used, and diabetes status (with or without diabetes).RESULTSCompared with euglycemia, executive functions (with one exception) were significantly impaired during hypoglycemia; lower test scores were recorded with more time required for completion. Large Cohen d values (>0.8) suggest that hypoglycemia induces decrements in aspects of executive function with large effect sizes. In some tests, the performance of participants with diabetes was more impaired than those without diabetes.CONCLUSIONS Executive cognitive function, which is necessary to carry out many everyday activities, is impaired during hypoglycemia in adults with and without type 1 diabetes. This important aspect of cognition has not received previous systematic study with respect to hypoglycemia. The effect size is large in terms of both accuracy and speed.</p
- …
