The design and construction of an electrochemical detector with two working electrodes located on the opposite walls of a thin-layer cell and its use as a detector for High Pressure Liquid Chromatography (HPLC) in the analysis of catecholamines in human cerebrospinal fluid are described. The location of the electrodes in this manner permits an electrochemically reversible or quasireversible couple to be electrolized more than once as it passes through the detector. If one electrode is held at a potential where oxidation takes place and the second electrode at a potential where reduction of this oxidized form back to the starting material occurs, then the current produced increases proportionately to the number of conversions that take place. A comparison of this cell in the dual-working-electrode and single-working-electrode mode shows an improvement in the signal-to-noise ratio by a factor of six. This HPLC system with electrochemical detection has been used for the first time to detect norephinephrine (141 pg/mL) and dopamine (262 pg/mL) in human cerebrospinal fluid.

No description available.

A detecção de antígenos em amostras de líquido cefalorraquiano (LCR) de pacientes com neurocisticercose (NC) foi realizada empregando-se o teste ELISA com soros policlonais de coelhos imunizados com os antígenos total de Taenia solium (T-Tso), líquido vesicular de Taenia crassiceps (LV-Tcra) e peptídeos <30kDa de LV-Tcra. Os soros policlonais foram fracionados para a obtenção da fração IgG - IgG anti-Tso, IgG antiTcra e IgG anti-Tcra<30kDa. Também foi empregado o anticorpo monoclonal específico para o antígeno de excreção e secreção de Taenia crassiceps (ES-Tcra). A seleção dos clones foi realizada por ELISA empregando-se os antígenos T-Tso e LV-Tcra. Foram analisados diferentes grupos de amostras divididos em: grupo de pacientes com NC (grupo NC), incluindo pacientes em diferentes fases evolutivas da doença, grupo de pacientes \"suspeito\" de NC (grupo \"suspeito\" NC), grupo controle (grupo C) e grupo de outros patologias (grupo OP). No teste ELISA empregando-se as frações IgG anti-Tso, IgG anti-Tcra e IgG anti-Tcra<30kDa, a sensibilidade obtida foi de 70%, 82,5% e 95,8% e a especificidade de 82,5%, 98% e 100%, respectivamente nas amostras do grupo NC e grupo C. Nas amostras do grupo diferentes fases evolutivas da doença, não houve diferença significativa de reatividade entre as amostras com as frações empregadas. Para as 21 amostras do grupo NC - fase ativa da doença, com a fração IgG anti-Tcra e o anticorpo monoclonal anti-ES-Tcra, respectivamente, 13 e 16 amostras foram positivas para a pesquisa de antígenos. As amostras de LCR do grupo C não apresentaram reatividade com os anticorpos empregados nos ensaios. Também foram ensaiadas 68 amostras de LCR de pacientes com \"suspeita\" de NC. De acordo com as características citoprotéicas além da reatividade para a pesquisa de anticorpos anti-T solium, as amostras de LCR apresentaram, neste grupo, padrão de reatividade para a pesquisa de antígenos que variou também de acordo com a presença de anticorpos, além das alterações de proteína e/ou células, que as amostras apresentavam ou não. Frações de 14 e 18kDa foram identificadas pelo teste imunoblot somente nas amostras de LCR de pacientes com NC utilizando as frações IgG anti-Tso, IgG anti-Tcra e anticorpo monoclonal anti-ES-Tcra. O anticorpo monoclonal anti-ES-Tcra mostrou-se eficiente para a pesquisa de antígenos no teste de competição por ELISA nas amostras de LCR de pacientes com NC e o antígeno ES-Tcra. / Antigen detection in cerebrospinal fluid (CSF) samples of patients with neurocysticercosis (NC) was performed through ELISA test using rabbits polyclonal sera immune with total antigens of Taenia solium (T-Tso) cysticercus, vesicular liquid of Taenia crassiceps (VL-Tcra) and vesicular liquid peptides (VLP-Tcra<30kDa) cysticercus. The polyclonal sera were separated obtaining IgG-lgG anti-Tso, IgG anti-Tcra and IgG anti-Tcra<30kDa fractions. A specific monoclonal antibody was also applied for reaching the excretion and secretion antigen of the T. crassiceps (ES-Tcra) larvae culture. Clones selection was performed through Elisa test applying the T-Tso and VL-Tcra antigens. When IgG anti-Tso, IgG anti-Tcra and IgG anti-Tcra<30kDa fractions were applied in the ELISA test, the accuracy obtained was 70%, 82,5% and 95,8% and the specificity of 82,5%, 98% and 100%, respectively, in samples of both NC and C groups. In the samples of the group in different stages of the disease there was no significant difference on reactivity between the samples when the fractions were applied. For the 21 samples of the NC group - active stage of the disease with IgG anti-Tcra fraction and the anti-ES-Tcra monoclonal antibody respectively, 13 and 16 samples were positive for antigen analyses. The CSF samples of the C group did not present reactivity with the antibodies applied in the tests. Tests for 68 CSF samples of \"suspected\" NC group, were also conducted. According to the cytoproteic characteristics besides the reactivity for the anti-T. solium antibody study, the CSF samples of this group showed standard reactivity for antigen detection ranging also in accordance with the presence of antibodies and of the protein and/or cell alterations that the samples would or not present. Fractions of 14 and 18kDa were identified by immunoblot test only in the CSF samples of patients with NC using the IgG anti-Tso IgG anti-Tcra fractions and the anti-ES-Tcra monoclonal antibody. The anti-ES-Tcra monoclonal antibody has shown to be efficient for analyzing antigens by a comparing method of the ELISA test in CSF samples of patients with NC and the ES-Tcra antigen.

A detecção de antígenos em amostras de líquido cefalorraquiano (LCR) de pacientes com neurocisticercose (NC) foi realizada empregando-se o teste ELISA com soros policlonais de coelhos imunizados com os antígenos total de Taenia solium (T-Tso), líquido vesicular de Taenia crassiceps (LV-Tcra) e peptídeos <30kDa de LV-Tcra. Os soros policlonais foram fracionados para a obtenção da fração IgG - IgG anti-Tso, IgG antiTcra e IgG anti-Tcra<30kDa. Também foi empregado o anticorpo monoclonal específico para o antígeno de excreção e secreção de Taenia crassiceps (ES-Tcra). A seleção dos clones foi realizada por ELISA empregando-se os antígenos T-Tso e LV-Tcra. Foram analisados diferentes grupos de amostras divididos em: grupo de pacientes com NC (grupo NC), incluindo pacientes em diferentes fases evolutivas da doença, grupo de pacientes \"suspeito\" de NC (grupo \"suspeito\" NC), grupo controle (grupo C) e grupo de outros patologias (grupo OP). No teste ELISA empregando-se as frações IgG anti-Tso, IgG anti-Tcra e IgG anti-Tcra<30kDa, a sensibilidade obtida foi de 70%, 82,5% e 95,8% e a especificidade de 82,5%, 98% e 100%, respectivamente nas amostras do grupo NC e grupo C. Nas amostras do grupo diferentes fases evolutivas da doença, não houve diferença significativa de reatividade entre as amostras com as frações empregadas. Para as 21 amostras do grupo NC - fase ativa da doença, com a fração IgG anti-Tcra e o anticorpo monoclonal anti-ES-Tcra, respectivamente, 13 e 16 amostras foram positivas para a pesquisa de antígenos. As amostras de LCR do grupo C não apresentaram reatividade com os anticorpos empregados nos ensaios. Também foram ensaiadas 68 amostras de LCR de pacientes com \"suspeita\" de NC. De acordo com as características citoprotéicas além da reatividade para a pesquisa de anticorpos anti-T solium, as amostras de LCR apresentaram, neste grupo, padrão de reatividade para a pesquisa de antígenos que variou também de acordo com a presença de anticorpos, além das alterações de proteína e/ou células, que as amostras apresentavam ou não. Frações de 14 e 18kDa foram identificadas pelo teste imunoblot somente nas amostras de LCR de pacientes com NC utilizando as frações IgG anti-Tso, IgG anti-Tcra e anticorpo monoclonal anti-ES-Tcra. O anticorpo monoclonal anti-ES-Tcra mostrou-se eficiente para a pesquisa de antígenos no teste de competição por ELISA nas amostras de LCR de pacientes com NC e o antígeno ES-Tcra. / Antigen detection in cerebrospinal fluid (CSF) samples of patients with neurocysticercosis (NC) was performed through ELISA test using rabbits polyclonal sera immune with total antigens of Taenia solium (T-Tso) cysticercus, vesicular liquid of Taenia crassiceps (VL-Tcra) and vesicular liquid peptides (VLP-Tcra<30kDa) cysticercus. The polyclonal sera were separated obtaining IgG-lgG anti-Tso, IgG anti-Tcra and IgG anti-Tcra<30kDa fractions. A specific monoclonal antibody was also applied for reaching the excretion and secretion antigen of the T. crassiceps (ES-Tcra) larvae culture. Clones selection was performed through Elisa test applying the T-Tso and VL-Tcra antigens. When IgG anti-Tso, IgG anti-Tcra and IgG anti-Tcra<30kDa fractions were applied in the ELISA test, the accuracy obtained was 70%, 82,5% and 95,8% and the specificity of 82,5%, 98% and 100%, respectively, in samples of both NC and C groups. In the samples of the group in different stages of the disease there was no significant difference on reactivity between the samples when the fractions were applied. For the 21 samples of the NC group - active stage of the disease with IgG anti-Tcra fraction and the anti-ES-Tcra monoclonal antibody respectively, 13 and 16 samples were positive for antigen analyses. The CSF samples of the C group did not present reactivity with the antibodies applied in the tests. Tests for 68 CSF samples of \"suspected\" NC group, were also conducted. According to the cytoproteic characteristics besides the reactivity for the anti-T. solium antibody study, the CSF samples of this group showed standard reactivity for antigen detection ranging also in accordance with the presence of antibodies and of the protein and/or cell alterations that the samples would or not present. Fractions of 14 and 18kDa were identified by immunoblot test only in the CSF samples of patients with NC using the IgG anti-Tso IgG anti-Tcra fractions and the anti-ES-Tcra monoclonal antibody. The anti-ES-Tcra monoclonal antibody has shown to be efficient for analyzing antigens by a comparing method of the ELISA test in CSF samples of patients with NC and the ES-Tcra antigen.

Die Liquordiagnostik im Rahmen von Demenzerkrankungen ist trotz neuer diagnostischer Möglichkeiten im Bereich der PET(Positronen-Emissions-Tomographie)-Bildgebung weiterhin von hoher klinischer Relevanz. Insbesondere für die Alzheimer-Erkrankung existieren validierte Biomarker, die die Diagnose untermauern und bei der diagnostischen Abgrenzung anderer Demenzätiologien hilfreich sein können.Während unauffällige Liquorbefunde mit negativen Demenz- und Destruktionsmarkern die überwiegende Mehrzahl neurodegenerativer Demenzursachen mit hoher diagnostischer Sicherheit ausschließen, stellen in der klinischen Praxis vor allem überlappende Biomarkerprofile bei primär neurodegenerativen Demenzursachen ein substanzielles Problem bei der Befundinterpretation dar. Deshalb bedarf die Liquorbefundinterpretation stets einer kontextualisierten Betrachtung unter Würdigung der klinischen Symptomatik und Verlaufscharakteristika des entsprechenden demenziellen Syndroms. Außerdem stellen auchMischbefunde eine häufige diagnostische Herausforderung dar, ür deren Interpretation es profunder Kenntnisse im Bereich von Präanalytik, möglicher Liquorbefundkonstellationen und natürlich der verschiedenen in Betracht kommenden Demenzätiologien bedarf. Auch Liquorbiomarker für Synukleinopathien, Tauopathien sowie TDP43(Transactive response DNA binding protein 43 kDa)-Proteinopathien sind Gegenstand aktueller Untersuchungen, wenngleich diese noch nicht den Weg in die klinische Routinediagnostik gefunden haben.