35 research outputs found

    The expression of wild-type pendrin (SLC26A4) in human embryonic kidney (HEK 293 Phoenix) cells leads to the activation of cationic currents

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    Objective: The SLC26A4 protein (pendrin) seems to be involved in the exchange of chloride with other anions, therefore being responsible for iodide organification in the thyroid gland and the conditioning of the endolymphatic fluid in the inner ear. Malfunction of SLC26A4 leads to Pendred syndrome, characterized by mild thyroid dysfunction often associated with goiter and/or prelingual deafness. The precise function of the SLC26A4 protein, however, is still elusive. An open question is still whether the SLC26A4-induced ion exchange mechanism is electrogenic or electroneutral. Recently, it has been shown that human pendrin expressed in monkey cells leads to chloride currents. Methods: We overexpressed the human SLC26A4 isoform in HEK293 Phoenix cells and measured cationic and anionic currents by the patch-clamp technique in whole cell configuration. Results: Here we show that human pendrin expressed in human cells does not lead to the activation of chloride currents, but, in contrast, leads to an increase of cationic currents. Conclusion: Our experiments suggest that the SLC26A4-induced chloride transport is electroneutral when expressed in human cellular systems

    Fast fluorometric method for measuring pendrin (SLC26A4) Cl-/I- transport activity

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    Malfunction of the SLC26A4 protein leads to Pendred syndrome, characterized by sensorineural hearing loss, often associated with mild thyroid, dysfunction and goiter. It is generally assumed that SLC26A4 acts as a chloride/anion exchanger, which in the thyroid gland transports iodide, and in the inner ear contributes to the conditioning of the endolymphatic fluid. Here we describe a fast fluorometric method able to be used to functionally scrutinize SLC26A4 and its mutants described in Pendred syndrome. The validation of the method was done by functionally characterizing the chloride/iodide transport of SLC26A4, and a mutant, i.e. SLC26A4(S28R') which we previously described in a patient with sensorineural hearing loss, hypothyroidism and goiter. Using the fluorometric method we describe here we can continuously monitor and quantify the iodide or chloride amounts transported by the cells, and we found that the transport capability of the SLC26A4(S28R) mutant protein is markedly reduced if compared to wild-type SLC26A4

    Functional characterization of wild-type and a mutated form of SLC26A4 identified in a patient with pendred syndrome

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    BACKGROUND: Malfunction of the SLC26A4 protein leads to prelingual deafness often associated with mild thyroid dysfunction and goiter. It is assumed that SLC26A4 acts as a chloride/anion exchanger responsible for the iodide organification in the thyroid gland, and conditioning of the endolymphatic fluid in the inner ear. METHODS: Chloride uptake studies were made using HEK293-Phoenix cells expressing human wild type SLC26A4 (pendrin) and a mutant (SLC26A4(S28R)) we recently described in a patient with hypothyroidism, goiter and sensorineural hearing loss. RESULTS: Experiments are summarized showing the functional characterization of wild type SLC26A4 and a mutant (S28R), which we described recently. This mutant protein is transposed towards the cell membrane, however, its transport capability is markedly reduced if compared to wild-type SLC26A4. Furthermore, we show that the SLC26A4 induced chloride uptake in HEK293-Phoenix cells competes with iodide, and, in addition, that the chloride uptake can be blocked by NPPB and niflumic acid, whereas DIDS is ineffective. CONCLUSIONS: The functional characteristics of SLC26A4(S28R) we describe here, are consistent with the clinical phenotype observed in the patient from which the mutant was derived

    Электроснабжение установки перекачки нефти п. Пионерный ОАО «Томскнефть»

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    РЕФЕРАТ Выпускная квалификационная работа 149 с., 23 рис., 32 табл., 29 источников, 6 прил. Ключевые слова: нефтепровод, насос, электрооборудование, схема электроснабжения, линия, сеть, электроприемник, нагрузка, оборудование, защита, ток, напряжение, мощность. Объектом исследования является электрическая часть УПН п. Пионерный ОАО «Томскенефть». Цель работы – проектирование схемы электроснабжения предприятия, выбор оборудования. В процессе исследования проводился сбор исходных данных в ходе производственной практики на объекте исследования. В результате была спроектирована схема электроснабжения от подстанции энергосистемы, до конечного электроприемника. Были выбраны кабели и провода, коммутационное оборудование, были сделаны необходимые проверки. Также результатом работы сталESSAY Final qualifying work 149 p., 23 fig., 32 tab., 29 sources, 6 adj. Keywords: oil, pump, electrical equipment, power supply circuit, line, network, power-consuming equipment, load equipment, protection, current, voltage, power. The object of research is the electrical part of UPN claim. Pionerny of "Tomskeneft". The purpose of work - designing enterprise power scheme, the choice of equipment. The study was conducted to collect baseline data in the course of practical training on the subject of the study. As a result, power supply circuit has been designed from the substation grid, appliance, to the end. Were selected cables and wires, switching equipment, the necessary checks have been made. It is also the result of the work became an economic calculation of capital costs for the con

    Laryngeales Kontaktgranulom: Laryngeal granuloma Ätiologie, Symptomatik, Diagnose und Therapie

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    Kontaktgranulome sind gutartige, meist einseitige chronisch entzündliche Erkrankungen im Bereich des Processus vocalis des Kehlkopfs. Auf der Gegenseite findet sich oft an korrespondierender Stelle ein Kontaktulkus. Fremdkörpergefühl, Räusperzwang, Heiserkeit und eine verminderte stimmliche Belastbarkeit stehen klinisch im Vordergrund, insbesondere bei Patienten mit Sprechberufen und mangelnder Stimmtechnik. Ein Malignom kann nahezu immer anamnestisch und klinisch ausgeschlossen werden, weshalb eine Biopsie nur bei Malignomverdacht begründet ist. Bei Verdacht auf eine gastroösophageale Refluxkrankheit (GERD) ist eine entsprechende fachärztliche Abklärung angezeigt. Das Therapieprinzip sollte aufgrund der Multikausalität für jeden Patienten entsprechend angepasst werden. Dabei soll eine logopädische Stimmtherapie als Basis jeglicher Therapie angeordnet werden. Eine Antirefluxtherapie sowie eine psychologische Beratung können gelegentlich hilfreich sein. Operative Abtragungen sollen vermieden werden wegen der Gefahr des Rezidivs. Anhand von 2 Fallbeispielen wird der klassische Verlauf des Krankheitsbildes geschildert und anschießend auf Ätiologie, Symptome, Diagnostik und Therapie eingegangen

    Richtungshören bimodal versorgter Patienten mit zeitlicher Abstimmung von Hörgerät und Cochlea-Implantat

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