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1.
Nervenarzt ; 86(7): 845-51, 2015 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-26099500

RESUMO

From 1 January 2019, after completion of the convergence phase, the Psychiatry Personnel Act (Psych-PV) will no longer be the basis of budget negotiations of psychiatric hospitals and departments with the health insurance funds in Germany. Instead, the new compounding remuneration system for psychiatric and psychosomatic inpatient institutions (PEPP) will provide a new framework. The Federal Joint Committee (Gemeinsamer Bundesausschuss, G-BA) has been given the task of elaborating a directive on the basis of the expiring Psych-PV in order to redefine standards for personnel allocation within this new framework. This task presupposes the existence of reliable data in the psychiatric hospitals and departments for categorizing patients following the Psych-PV. It presupposes further that these data allow an exact calculation of the personnel to which the clinics are entitled. This article shows that the so-called §-21 dataset from the database of the VIPP project (indicators of patient care in psychiatric and psychosomatic facilities) allows this calculation. The VIPP dataset was used as a basis to calculate the personnel requirements. Exemplary analyses illustrate that the information available regarding the Psych-PV can be transformed in minutes per day, minutes per month and full time positions. Therefore, this information would also be available to the Institute for the Hospital Remuneration System (InEK).


Assuntos
Mão de Obra em Saúde/economia , Avaliação das Necessidades/economia , Psiquiatria/economia , Alocação de Recursos/economia , Alemanha , Mão de Obra em Saúde/estatística & dados numéricos , Avaliação das Necessidades/legislação & jurisprudência , Mecanismo de Reembolso/economia , Mecanismo de Reembolso/legislação & jurisprudência , Alocação de Recursos/métodos , Carga de Trabalho/economia , Carga de Trabalho/legislação & jurisprudência
2.
Fortschr Neurol Psychiatr ; 82(11): 634-9, 2014 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-25383930

RESUMO

The development of the lump-sum reimbursement System in psychiatry and psychosomatics (PEPP) (Klimke et al., 2014) is being negatively considered - also in gerontopsychiatry.Thus it is reasonable to make a timely analysis of the effects of PEPP on health-care structures. For this two analyses have been carried out. On the one hand the day mix index of elderly patients (> 64 years) was compared with that of younger ones (> 17 years, < 65 years). On the other hand younger and older were included in the analysis with regard to the available treatment minutes in exact daily classifications according to the PsychPV. It is seen that evaluation of the individual day was markedly higher for gerontopsychiatric patients not only in inpatient (difference > 0.1) but also in outpatient (difference > 0.07) setting. The exact daily classifications according to PsychPV, however, were markedly poorer for the elderly patients. Thus, on the basis of routine data of VIPP projects, a clear change can be seen in favour of the elderly patient under PEPP conditions as compared to financing according to PsychPV. However, concern remains that the ageing population and modernisation of therapy are not being sufficiently taken into account. The new reimbursement system merely regulates the distribution of available resources; if these resources are too low nothing will change by the PEPP-System.


Assuntos
Idoso/psicologia , Reembolso de Seguro de Saúde/economia , Psiquiatria/economia , Medicina Psicossomática/economia , Adolescente , Adulto , Fatores Etários , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Grupos Diagnósticos Relacionados , Feminino , Alemanha , Recursos em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , População , Adulto Jovem
3.
Fortschr Neurol Psychiatr ; 82(7): 394-400, 2014 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-25014202

RESUMO

INTRODUCTION: In Germany a new and unique remuneration system for psychiatric and psychosomatic stationary treatments (PEPP system) was introduced in 2013 on an optional basis. From 2015 it will be mandatory for psychiatric and psychosomatic facilities. The introduction of the PEPP system brings up different questions regarding the possible incentives of the new remuneration system and its effects on the supply of psychiatric and psychosomatic treatments. To conduct these necessary analyses a reliable database is needed. MATERIAL AND METHODS: The goal of the project "Indicators of patient care in Psychiatric and Psychosomatic Facilities" (VIPP project) is to gather a representative database which reflects the situation of day-to-day patient care performed by German psychiatric and psychosomatic facilities. The §â€Š21 data set represents the basis of this database which will be complemented by other data sources (i. e., financial statements and other economic data). A number of more than 100 ,000 cases per year has already been exceeded. These case data were provided by a wide range of psychiatric hospitals, departments and universities that participate in this project. The dataset is anonymised and by pooling the data it is not possible to identify the cases of a specific clinic. Participants receive a web-based access and have the possibility to analyse the data independently. RESULTS: Using the examples of coding accuracy and rehospitalisation rates the variety as well as the enormous potential of this database can be demonstrated. DISCUSSION: On the base of the VIPP database valid patient care indicators can be identified and cross-sectional analyses can be conducted. From such results key data on health economic strategies can be derived and the incentives, strengths and limitations of this constantly changing system can be identified.


Assuntos
Instalações de Saúde/estatística & dados numéricos , Transtornos Mentais/terapia , Assistência ao Paciente/estatística & dados numéricos , Psiquiatria/estatística & dados numéricos , Transtornos Psicofisiológicos/terapia , Medicina Psicossomática/estatística & dados numéricos , Adulto , Idoso , Estudos Transversais , Bases de Dados Factuais , Geriatria/legislação & jurisprudência , Geriatria/estatística & dados numéricos , Alemanha , Humanos , Psiquiatria/legislação & jurisprudência , Medicina Psicossomática/legislação & jurisprudência , Qualidade da Assistência à Saúde
4.
Gesundheitswesen ; 76(8-9): 479-85, 2014 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-24493579

RESUMO

BACKGROUND: Against the background of the continuously growing incidence rates of gerontopsychiatric disorders, their economic dimen-sions, and the effects on persons affected as well as their social environments, the present study focuses on an analysis of the services provided in acute psychiatric care settings for patients with dementia. RESULTS are based on secondary data. AIM OF THE STUDY: We aim to compare therapeutic service units of different clusters of occupational groups (physicians/psychologists, nurses/special therapists) for the ICD-10 diagnostic groups F00-F03 and G30 in the years 2010 (starting with July) and 2011. Main research question is how many patients are mappable with 'therapeutic units' (Therapieeinheiten, TE) of the operation and procedures catalogue (OPS). METHODS: The present study is based on an analysis of the §21 KHEntgG data record of 35 acute psychiatric facilities. Data collection took place within the project "Versorgungsindikatoren für die Psychiatrie und Psychosomatik (VIPP)", "Supply indicators for psychiatric and psychosomatic settings". The data record implies statewide data of specialised hospitals, university hospitals and departments of psychiatry of the Federal Republic of Germany. RESULTS: In total, 5 111 cases were included in the analysis. Nurses and special therapists carried out significantly more therapeutic units in the main diagnoses groups (F01, F03 and G30) and the care groups (regular vs. intensive) than physicians and psychologists (p<0.05). It was not possible to map all patients with the use of therapeutic units (G30 78.8%, F01 83.4%, F03 81.2%). Mapping of patients was significantly higher in the intensive care compared to regular care in both occupational clusters (p<0.05). CONCLUSIONS: We demonstrated that the "therapeutic units" of the OPS codes are now used in the routine data (§21 KHEntgG), and that they are able to portray relevant aspects of non-medication therapeutic service. The present study provides a preliminary/exploratory overview on the services provided, mapped by therapeutic units. Future research should focus on the overlap between the category "therapeutic" units and the services actually provided.


Assuntos
Demência/classificação , Demência/terapia , Registros Eletrônicos de Saúde/classificação , Hospitais Psiquiátricos/estatística & dados numéricos , Classificação Internacional de Doenças/estatística & dados numéricos , Psicoterapia/classificação , Psicoterapia/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Demência/epidemiologia , Registros Eletrônicos de Saúde/estatística & dados numéricos , Feminino , Alemanha/epidemiologia , Hospitais Psiquiátricos/classificação , Humanos , Masculino
5.
Nervenarzt ; 85(1): 88-95, 2014 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-24399501

RESUMO

BACKGROUND: In Germany a new reimbursement system for psychiatry and psychosomatics is under development. Based on total costs of each case from selected hospitals and day clinics, in 2013 the Institute for the Hospital Remuneration System (InEK) proposed to reimburse the hospital costs daily with step-wise decreasing remuneration, mainly depending on the ICD-10 diagnosis, duration of stay and some complicating factors (PEPP grouper). It is controversial whether this degressive system will result in an inadequate remuneration of patients with longer duration of severe symptoms, such as suicidality in depression or autoaggressive behavior in borderline personality disorder and will eventually lead to advantages for acutely ill patients with short duration of stay compared to chronically ill patients. OBJECTIVES: This study formulated and tested an alternative remuneration system (proof of concept) mainly based on an analysis of daily cost data instead of the total costs of each case. MATERIAL AND METHODS: The study is based on 147,749 treatment days from 4,633 cases of patients with psychotic disorders (PEPP-PA03) in 6 hospitals. As possible cost separating factors the study analyzed days with and without intensive psychiatric care, 1 to 1 care, psychological diagnostics, magnetic resonance imaging (MRI), acute crisis intervention, age at admission, the first days of treatment and day of discharge. RESULTS AND DISCUSSION: Nearly all factors tested were shown to be statistically significant in separating daily hospital costs. Based on these findings an alternative calculation algorithm (TEPPconcret), which grouped the cases with respect to age, intensive care, 1 to 1 care, treatment days 1-4 and day of discharge, was formulated and tested. For psychotic disorders TEPPconcret with a basic rate complemented by daily add-on payments depending on the effort involved, is a serious alternative to the PEPP system and awaits further evaluation.


Assuntos
Custos de Cuidados de Saúde/estatística & dados numéricos , Tempo de Internação/economia , Transtornos Mentais/economia , Transtornos Mentais/terapia , Psiquiatria/economia , Mecanismo de Reembolso/economia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Transtornos Mentais/diagnóstico , Pessoa de Meia-Idade , Projetos Piloto , Prevalência , Medicina Psicossomática/economia
7.
J Microsc ; 233(1): 42-60, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19196411

RESUMO

Current biomedical research increasingly requires imaging large and thick 3D structures at high resolution. Prominent examples are the tracking of fine filaments over long distances in brain slices, or the localization of gene expression or cell migration in whole animals like Caenorhabditis elegans or zebrafish. To obtain both high resolution and a large field of view (FOV), a combination of multiple recordings ('tiles') is one of the options. Although hardware solutions exist for fast and reproducible acquisition of multiple 3D tiles, generic software solutions are missing to assemble ('stitch') these tiles quickly and accurately. In this paper, we present a framework that achieves fully automated recombination of tiles recorded at arbitrary positions in 3D space, as long as some small overlap between tiles is provided. A fully automated 3D correlation between all tiles is achieved such that no manual interaction or prior knowledge about tile positions is needed. We use (1) phase-only correlation in a multi-scale approach to estimate the coarse positions, (2) normalized cross-correlation of small patches extracted at salient points to obtain the precise matches, (3) find the globally optimal placement for all tiles by a singular value decomposition and (4) accomplish a nearly seamless stitching by a bleaching correction at the tile borders. If the dataset contains multiple channels, all channels are used to obtain the best matches between tiles. For speedup we employ a heuristic method to prune unneeded correlations, and compute all correlations via the fast Fourier transform (FFT), thereby achieving very good runtime performance. We demonstrate the successful application of the proposed framework to a wide range of different datasets from whole zebrafish embryos and C. elegans, mouse and rat brain slices and fine plant hairs (trichome). Further, we compare our stitching results to those of other commercially and freely available software solutions. The algorithms presented are being made available freely as an open source toolset 'XuvTools' at the corresponding author's website (http://lmb.informatik.uni-freiburg.de/people/ronneber), licensed under the GNU General Public License (GPL) v2. Binaries are provided for Linux and Microsoft Windows. The toolset is written in templated C++, such that it can operate on datasets with any bit-depth. Due to the consequent use of 64bit addressing, stacks of arbitrary size (i.e. larger than 4 GB) can be stitched. The runtime on a standard desktop computer is in the range of a few minutes. A user friendly interface for advanced manual interaction and visualization is also available.


Assuntos
Imageamento Tridimensional/métodos , Animais , Caenorhabditis elegans/anatomia & histologia , Camundongos , Plantas/anatomia & histologia , Ratos , Peixe-Zebra/anatomia & histologia
8.
Cell Death Differ ; 15(9): 1396-407, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18437160

RESUMO

The RNA alphavirus Semliki Forest (SFV) triggers apoptosis in various mammalian cells, but it has remained controversial at what infection stage and by which signalling pathways host cells are killed. Both RNA synthesis-dependent and -independent initiation processes and mitochondrial as well as death receptor signalling pathways have been implicated. Here, we show that SFV-induced apoptosis is initiated at the level of RNA replication or thereafter. Moreover, by expressing antiapoptotic genes from recombinant SFV (replicons) and by using neutralizing reagents and gene-knockout cells, we provide clear evidence that SFV does not require CD95L-, TRAIL (tumor necrosis factor-related apoptosis-inducing ligand)- or tumor necrosis factor-mediated signalling but mitochondrial Bak to trigger cytochrome c release, the fall in the mitochondrial membrane potential, apoptotic protease-activating factor-1/caspase-9 apoptosome formation and caspase-3/-7 activation. Of seven BH3-only proteins tested, only Bid contributed to effective SFV-induced apoptosis. However, caspase-8 activation and Bid cleavage occurred downstream of Bax/Bak, indicating that truncated Bid formation serves to amplify rather than trigger SFV-induced apoptosis. Our data show that SFV sequentially activates a mitochondrial, Bak-mediated, caspase-8-dependent and Bid-mediated death signalling pathway that can be accurately dissected with gene-knockout cells and SFV replicons carrying antiapoptotic genes.


Assuntos
Apoptose , RNA Viral/biossíntese , Vírus da Floresta de Semliki/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Aedes/citologia , Animais , Proteínas Reguladoras de Apoptose/genética , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/fisiologia , Caspase 8/metabolismo , Caspases/metabolismo , Citocromos c/metabolismo , Genoma Viral , Mitocôndrias/metabolismo , Replicon , Transdução de Sinais , Proteína X Associada a bcl-2/metabolismo
9.
Histopathology ; 51(1): 87-97, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17593084

RESUMO

AIMS: To investigate the modulation of cellular retinol-binding protein (CRBP)-1 and the desmosomal plaque proteins plakophilin (PKP)-1 and desmoplakin (DP) in correlation with the Ki67+ proliferation index (PI) during the progression of cervical squamous intraepithelial lesions (SIL) to squamous cell carcinoma (SCC). METHODS: Using in situ imaging by brightfield and confocal laser scanning microscopy, the expression of CRBP-1 protein and transcripts, PKP-1, DP and the Ki67 PI were analysed in 38 low-grade (L) SIL, 56 high-grade (H) SIL, 49 SCC, 30 control cervices and 10 human papillomavirus-positive condylomatous lesions. RESULTS: CRBP-1+ cells increased from 11.4% in the normal cervix to 80.3% in LSILs, 92.3% in HSILs and slightly decreased to 78.3% in invasive SCCs (P = 0.0001) in close association with the Ki67 PI (r =0.41; P < 0.0001). PKP-1+ and DP+ cells were correlated (0.32; P < 0.0001) and decreased from normal (81% versus 92.3%) to LSIL (53.1% versus 85.3%), to HSIL (46.4% versus 67.5%) and SCC (35.1% versus 35.9%). The Ki67+ PI was inversely correlated with DP (-0.20, P = 0.0014) and PKP-1 (-0.19, P = 0.015). Condylomata retained low CRBP-1 and high expression of PKP-1 and DP. CONCLUSIONS: The gain of CRBP-1 and the loss of desmosomal proteins occur early in cervical carcinogenesis.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Desmoplaquinas/metabolismo , Antígeno Ki-67/metabolismo , Placofilinas/metabolismo , Proteínas de Ligação ao Retinol/metabolismo , Neoplasias do Colo do Útero/metabolismo , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Proliferação de Células , Transformação Celular Neoplásica/genética , Colo do Útero/metabolismo , Colo do Útero/patologia , Condiloma Acuminado/metabolismo , Condiloma Acuminado/patologia , Desmoplaquinas/genética , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Antígeno Ki-67/genética , Placofilinas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação ao Retinol/genética , Proteínas Celulares de Ligação ao Retinol , Neoplasias do Colo do Útero/patologia
10.
J Microsc ; 222(Pt 1): 15-21, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16734709

RESUMO

Combined time-lapse imaging with optical marking of fluorescent proteins (FPs) is a widely used method in studies of the dynamic behaviour of proteins, organelles and cell populations. Most of the approaches have specific limitations as they do not permit simultaneous observation of marked and non-marked molecules, require co-expression of two FP-tagged proteins or rely on oligomerizing FPs. Here we provide a strategy to overcome such limitations with a fluorescence resonance energy transfer-competent tandem fusion tag composed of two FPs. We combine optical marking by acceptor photobleaching with spectral imaging to discriminate between marked and non-marked molecules. Such 'bleach-labelling' may be employed in a broad range of studies for robust real-time tracking of proteins, organelles and cells.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Proteínas Recombinantes de Fusão/metabolismo , Sequência de Aminoácidos , Animais , Células COS , Chlorocebus aethiops , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Microscopia de Fluorescência/métodos , Óptica e Fotônica , Fotodegradação , Proteínas Recombinantes de Fusão/genética , Espectrometria de Fluorescência
11.
J Lipid Res ; 46(11): 2325-38, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16150831

RESUMO

To examine the possibility of targeting liposomes to hepatocytes via bile salts, the bile salt lithocholyltaurine was covalently linked to a phospholipid. The isomeric compounds disodium 3alpha-(2-(1,2-O-distearoyl-sn-glycero-3-phospho-2'-ethanolamidosuccinyloxy)ethoxy)-5beta-cholan-24-oyl-2'-aminoethansulfonate and disodium 3beta-(2-(1,2-O-distearoyl-sn-glycero-3-phospho-2'-ethanolamidosuccinyloxy)ethoxy-5beta-cholan-24-oyl-2'-aminoethansulfonate (DSPE-3beta-LCT) were synthesized and incorporated into liposomal membranes. Confocal laser scanning microscopy studies showed that bile salt-bearing liposomes (BSLs) attach to the surface of rat hepatocytes in culture. Studies with radioactively labeled liposomes revealed that the bile salt linked via the 3beta-conformation resulted in a higher attachment efficiency than that with the 3alpha-derivative. In the presence of BSLs corresponding to 2 mM liposomal phosphatidylcholine, uptake of 50 microM cholyltaurine (CT) into hepatocytes was reduced by approximately 40% by the 3beta-derivative and by approximately 17% by the 3alpha-derivative. When added simultaneously with the liposomes, CT up to 75 microM inhibited the binding of DSPE-3beta-LCT-bearing liposomes. By contrast, increasing concentrations reversed this inhibition and resulted in an increased bile salt-mediated binding. The same was true when CT was added 10 min before the liposomes were added. The attachment of BSLs to the surface of hepatocytes opens up promising possibilities for hepatocyte-specific drug delivery. More generally, not only substrates for cellular endocytosing receptors but also substrates for cellular carrier proteins should be suitable ligands for the cell-specific targeting of nanoscale particles such as liposomes.


Assuntos
Ácidos e Sais Biliares/química , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Lipossomos/química , Fosfolipídeos/química , Animais , Células Cultivadas , Sistemas de Liberação de Medicamentos , Endocitose , Ésteres , Hepatócitos/metabolismo , Ligantes , Lipossomos/metabolismo , Masculino , Microscopia Confocal , Modelos Químicos , Modelos Teóricos , Fosfatidilcolinas/química , Ligação Proteica , Ratos , Ratos Wistar , Sais/química , Estereoisomerismo , Ácido Taurocólico/química , Fatores de Tempo
12.
J Fluoresc ; 15(3): 337-62, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15986157

RESUMO

The scope of this paper is to illustrate the need for an improved quality assurance in fluorometry. For this purpose, instrumental sources of error and their influences on the reliability and comparability of fluorescence data are highlighted for frequently used photoluminescence techniques ranging from conventional macro- and microfluorometry over fluorescence microscopy and flow cytometry to microarray technology as well as in vivo fluorescence imaging. Particularly, the need for and requirements on fluorescence standards for the characterization and performance validation of fluorescence instruments, to enhance the comparability of fluorescence data, and to enable quantitative fluorescence analysis are discussed. Special emphasis is dedicated to spectral fluorescence standards and fluorescence intensity standards.

13.
J Membr Biol ; 186(2): 89-100, 2002 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11944086

RESUMO

Thimerosal (o-Ethylmercurithio)benzoic acid, TMS), a membrane-impermeable, sulfhydryl-oxidizing agent, has been described to increase the K+ current IKs in KCNE1-injected Xenopus laevis oocytes. Since there are no cysteine residues in the extracellular domain of KCNE1, it has been proposed that TMS interacts with its partner protein KCNQ1. The aim of this study was therefore to investigate the interaction of TMS with KCNQ1 and the respective K+current IK. In CHO cells stably transfected with KCNQ1/KCNE1, TMS increased IKs, whereas in CHO cells expressing KCNQ1 alone, TMS initially decreased IK. TMS also affected the cytosolic pH (pHi) and the cytosolic Ca2+ activity ([Ca2+]i) in these cells. TMS slowly decreased pHi. With a short delay, TMS increased [Ca2+]i by store depletion and capacitative influx. The time course of the effects of TMS on pHi and [Ca2+]i did not correlate with the effect of TMS on IK. We therefore anticipated a different mode of action by TMS and investigated the influence of TMS on cysteine residues of KCNQ1. For this purpose, KCNQ1wt and two mutants lacking a cysteine residue in the S6 or the S3 segment (KCNQ1C331A and KCNQ1C214A, respectively) were expressed in Xenopus laevis oocytes. A sustained current decrease was observed in KCNQ1wt and KCNQ1C331A, but not in KCNQ1C214A-injected oocytes. The analysis of tail currents, I/V curves and activation kinetics revealed a complex effect of TMS on the gating of KCNQ1wt and KCNQ1C331A. In another series we investigated the effect of TMS on IKs. TMS increased IKs of KCNQ1C214A/KCNE1-injected oocytes significantly less than IKs in KCNQ1wt/KCNE1- or KCNQ1C331A/KCNE1-injected cells. These results suggest that thimerosal interacts with the cysteine residue C214 in the S3 segment of KCNQ1, leading to a change of its gating properties. Our results support the idea that not only the inner shell, but also the outer shell of the channel is important for the gating behavior of voltage dependent K+ channels.


Assuntos
Ativação do Canal Iônico/efeitos dos fármacos , Oxidantes/farmacologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Canais de Potássio/fisiologia , Timerosal/farmacologia , Animais , Células CHO , Cálcio/metabolismo , Cricetinae , Condutividade Elétrica , Humanos , Concentração de Íons de Hidrogênio , Canais de Potássio KCNQ , Canal de Potássio KCNQ1 , Oócitos , Canais de Potássio/genética , Xenopus laevis
14.
Pflugers Arch ; 443(5-6): 822-8, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11889581

RESUMO

KCNE1 (IsK, minK) co-assembles with KCNQ1 (KvLQT1) to form voltage-dependent K(+) channels. Both KCNQ1 and KCNE1 are expressed in epithelial cells of gut and exocrine pancreas. We examined the role of KCNQ1/KCNE1 in Cl(-) secretion in small and large intestine and exocrine pancreas using the KCNE1 knockout mouse. Immunofluorescence revealed a similar basolateral localization of KCNQ1 in jejunum and colon of KCNE1 wild-type and knockout mice. Electrogenic Cl(-) secretion in the colon was not affected by gene disruption of KCNE1; in jejunum forskolin-induced short-circuit current was some 40% smaller but without being significantly different. Inhibition of KCNQ1 channels by 293B (IC(50) 1 micromol l(-1)) and by IKS224 (IC(50) 14 nmol l(-1)) strongly diminished intestinal Cl(-) secretion. In exocrine pancreas of wild-type mice, KCNQ1 was predominantly located at the basolateral membrane. In KCNE1 knockout mice, however, the basolateral staining was less pronounced and the distribution of secretory granules was irregular. A slowly activating and 293B-sensitive K(+) current was activated via cholinergic stimulation in pancreatic acinar cells of wild-type mice. In KCNE1 knockout mice this K(+) current was strongly reduced. In conclusion intestinal Cl(-) secretion is independent from KCNE1 but requires KCNQ1. In mouse pancreatic acini KCNQ1 probably co-assembled with KCNE1 leads to a voltage-dependent K(+) current that might be of importance for electrolyte and enzyme secretion.


Assuntos
Mucosa Intestinal/metabolismo , Pâncreas/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Canais de Potássio/genética , Canais de Potássio/metabolismo , Animais , Cloretos/metabolismo , Colo/metabolismo , Mucosa Intestinal/química , Jejuno/metabolismo , Canais de Potássio KCNQ , Canal de Potássio KCNQ1 , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Knockout , Pâncreas/química , Técnicas de Patch-Clamp , Potássio/metabolismo , Canais de Potássio/análise
16.
Pathologe ; 22(2): 105-13, 2001 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-11321726

RESUMO

Gastroenteropancreatic endocrine or neuroendocrine tumors (NETs) encompass a broad spectrum of neoplasms characterized by a heterogeneous biological behavior. They differ with regard to functional state, localization, and derivation from various segments of the primitive embryonal gut, growth pattern, degree of differentiation, expression of different neuroendocrine marker molecules, and prognosis. They occur generally as sporadic tumors but sometimes also in the setting of a familial cancer syndrome such as in type 1 multiple endocrine neoplasia or von Hippel-Lindau syndrome. The complex manifestations of NETs are reflected by the varying terms and classification systems. However, the terms "carcinoid" and islet cell tumor" do not indicate whether the tumors are benign, malignant, or of uncertain behavior. New clinical, morphological, and molecular developments in the field of neuroendocrine biology are contributing to the identification and characterization of NETs and are considered in the current World Health Organization classification.


Assuntos
Neoplasias Intestinais/patologia , Tumores Neuroendócrinos/classificação , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Neoplasias Gástricas/patologia , Diagnóstico Diferencial , Humanos , Neoplasias Intestinais/classificação , Neoplasias Pancreáticas/classificação , Neoplasias Gástricas/classificação
17.
Gastroenterology ; 120(6): 1363-71, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11313306

RESUMO

BACKGROUND & AIMS: Gastric H+ secretion via the H+/K+-adenosine triphosphatase is coupled to the uptake of K+. However, the molecular identity of luminal K+ channels enabling K+ recycling in parietal cells is unknown. This study was aimed to investigate these luminal K+ channels. METHODS: Acid secretion was measured in vivo and in vitro; KCNQ1 protein localization was assessed by immunofluorescence, and acid-sensitivity of KCNQ1 by patch-clamp. RESULTS: We identified KCNQ1, which is mutated in cardiac long QT syndrome, as a K+ channel located in tubulovesicles and apical membrane of parietal cells, where it colocalized with H+/K+-adenosine triphosphatase. Blockade of KCNQ1 current by 293B led to complete inhibition of acid secretion. The putative KCNQ1 subunits, KCNE2 and KCNE3, were abundant in human stomach; KCNE1, however, was absent. Coexpression of KCNE3/KCNQ1 in COS cells led to an acid-insensitive current; KCNE2/KCNQ1 was activated by low extracellular pH. CONCLUSIONS: We identified KCNQ1 as the missing luminal K+ channel in parietal cells and characterized its crucial role in acid secretion. Because KCNE3 and KCNE2 are expressed in human stomach, one or both are candidates to coassemble with KCNQ1 in parietal cells. Thus, stomach- and subunit-specific inhibitors of KCNQ1 might offer new therapeutical perspectives for peptic ulcer disease.


Assuntos
Ácido Gástrico/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Canais de Potássio/fisiologia , Sequência de Aminoácidos , Animais , Células CHO , Cricetinae , Cães , Determinação da Acidez Gástrica , Histamina/farmacologia , Humanos , Canais de Potássio KCNQ , Canal de Potássio KCNQ1 , Masculino , Camundongos , Dados de Sequência Molecular , Bloqueadores dos Canais de Potássio , Canais de Potássio/análise , Coelhos , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie
19.
Exp Nephrol ; 8(6): 332-42, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11014930

RESUMO

In most epithelial tissues Cl(-) transport relies on the cystic fibrosis transmembrane conductance regulator (CFTR) which has dual function as a Cl(-) channel and as a regulator of other ion channels. More than 900 different mutations in the CFTR gene are the cause for defective transport of Cl(-) and Na(+) and impaired secretion or absorption of electrolytes in cystic fibrosis. However, the CFTR mutation delta F508 is the most common reason for the frequently inherited disease among the Caucasian population. Maturation and processing of delta F508-CFTR is defective which leads to expression of only very little but functional CFTR in the cell membrane. Understanding the processing and trafficking of CFTR may give a clue to the question as to how the expression and residual function of delta F508-CFTR can be enhanced, and may lead to the development of new pharmacological tools for the treatment of cystic fibrosis.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Processamento de Proteína Pós-Traducional , Animais , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/química , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/fisiologia , Endocitose/fisiologia , Células Epiteliais/metabolismo , Exocitose/fisiologia , Humanos , Mutação/fisiologia , Distribuição Tecidual
20.
Biochem Biophys Res Commun ; 275(2): 322-7, 2000 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-10964665

RESUMO

A new cell line was derived from primary culture of rat choroid plexus (RCP) by immortalization with the TSOri minus adenovirus. The selected clone expressed vasopressin V1a receptors at a density of 64,000 sites per cell, and a K(d) of 7.2 nM. Addition of vasopressin to the RCP cells induced a transient calcium peak comparable to V1a receptor signalling in different expression systems. This [Ca(2+)](i) increase was dose-dependent with an EC(50) of 22 nM vasopressin. Similar [Ca(2+)](i) increase was elicited by addition of serotonin, angiotensin II, endothelin-1, and bradykinin. Heterologous desensitization of V1a receptor was observed in RCP cells exposed to the phorbol ester PMA or following stimulation of other receptors coupled to the phosphoinositide pathway. Positive immunolabelling with Factor VIII, Flt1 and CD 34 antibodies suggests that this new RCP cell line originated from endothelial cells of rat choroid plexus.


Assuntos
Plexo Corióideo/metabolismo , Receptores de Vasopressinas/metabolismo , Transdução de Sinais , Animais , Sinalização do Cálcio , Linhagem Celular , Plexo Corióideo/citologia , Imuno-Histoquímica , Ligação Proteica , Ratos , Ratos Wistar
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