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1.
Article in English | MEDLINE | ID: mdl-35988107

ABSTRACT

PURPOSE: Early detection of bleeding is important for managing trauma cases in the emergency department (ED). Several trauma suites are equipped with computed tomography (CT) scanners to reduce the time to CT. In the last decade, sliding gantry CT has been implemented in trauma suites, highlighting conventional techniques' advantages. We investigated the change in the time to CT and the challenges faced during the implementation. METHODS: Trauma suite treatments with a conventional CT scanner between January and December 2016 formed the control group. From January to April 2017, trauma suites were modified, and treatment was outsourced to an interim trauma suite. By May 2017, trauma suites were equipped with a sliding gantry CT scanner. Treatments from May to July 2017 formed the transition group, and those from August to December 2017 formed the routine use group. We evaluated the time to CT in all groups and considered the reasons for the delays in the transition and routine use groups. RESULTS: On sliding gantry CT implementation, although time to CT remained unaffected in the transition group, it significantly reduced in the routine use group, independent of injury severity score. The incidence of cable management problems was significantly higher in the latter group. CONCLUSIONS: We have demonstrated a decrease in the time to CT with the implementation of a sliding gantry CT. However, due to a higher number of cable management problems in the routine use group, we recommend regular refresher team training with routine use.

2.
Stud Health Technol Inform ; 294: 573-574, 2022 May 25.
Article in English | MEDLINE | ID: mdl-35612150

ABSTRACT

The complexity of emergency cases and the number of emergency patients have increased dramatically. Due to a reduced or even missing specialist medical staff in the emergency departments (EDs), medical knowledge is often used without professional supervision for the diagnosis. The result is a failure in diagnosis and treatment, even death in the worst case. Secondary: high expenditure of time and high costs. Using accurate patient data from the German national registry of the medical emergency departments (AKTIN-registry, Home - Notaufnahmeregister (aktin.org)), the most 20 frequent diagnoses were selected for creating explainable artificial intelligence (XAI) models as part of the ENSURE project (ENSURE (umg.eu)). 137.152 samples and 51 features (vital signs and symptoms) were analyzed. The XAI models achieved a mean area under the curve (AUC) one-vs-rest of 0.98 for logistic regression (LR) and 0.99 for the random forest (RF), and predictive accuracies of 0.927 (LR) and 0.99 (RF). Based on its grade of explainability and performance, the best model will be incorporated into a portable CDSS to improve diagnoses and outcomes of ED treatment and reduce cost. The CDSS will be tested in a clinical pilot study at EDs of selected hospitals in Germany.


Subject(s)
Artificial Intelligence , Decision Support Systems, Clinical , Area Under Curve , Humans , Logistic Models , Pilot Projects
3.
Intern Emerg Med ; 17(4): 1199-1209, 2022 06.
Article in English | MEDLINE | ID: mdl-34989969

ABSTRACT

Several indicators reflect the quality of care within emergency departments (ED). The length of stay (LOS) of emergency patients represents one of the most important performance measures. Determinants of LOS have not yet been evaluated in large cohorts in Germany. This study analyzed the fixed and influenceable determinants of LOS by evaluating data from the German Emergency Department Data Registry (AKTIN registry). We performed a retrospective evaluation of all adult (age ≥ 18 years) ED patients enrolled in the AKTIN registry for the year 2019. Primary outcome was LOS for the whole cohort; secondary outcomes included LOS stratified by (1) patient-related, (2) organizational-related and (3) structure-related factors. Overall, 304,606 patients from 12 EDs were included. Average LOS for all patients was 3 h 28 min (95% CI 3 h 27 min-3 h 29 min). Regardless of other variables, patients admitted to hospital stayed 64 min longer than non-admitted patients. LOS increased with patients' age, was shorter for walk-in patients compared to medical referral, and longer for non-trauma presenting complaints. Relevant differences were also found for acuity level, day of the week, and emergency care levels. We identified different factors influencing the duration of LOS in the ED. Total LOS was dependent on patient-related factors (age), disease-related factors (presentation complaint and triage level), and organizational factors (weekday and admitted/non-admitted status). These findings are important for the development of management strategies to optimize patient flow through the ED and thus to prevent overcrowding.


Subject(s)
Emergency Service, Hospital , Quality Indicators, Health Care , Adolescent , Adult , Humans , Length of Stay , Registries , Retrospective Studies
4.
BMC Emerg Med ; 22(1): 5, 2022 01 11.
Article in English | MEDLINE | ID: mdl-35016633

ABSTRACT

BACKGROUND: Compelling data on clinical emergency medicine is required for healthcare system management. The aim of this survey was to describe the nationwide status quo of emergency care in Germany at the healthcare system level using the Utstein reporting template as the guideline to measure the data collected. METHODS: This cross-sectional survey collected standardized data from German EDs in 2018. All 759 of the EDs listed in a previously collected ED Directory were contacted in November 2019 using the online-survey tool SoSci Survey. Exclusively descriptive statistical analyses were performed. Absolute as well as relative frequencies, medians, means, ranges, standard deviations (SD) and interquartile ranges (IQR) were reported depending on distribution. MAIN RESULTS: A total of 150 questionnaires of contacted EDs were evaluated (response rate: 19.8%). Hospitals had a median of 403 inpatient beds (n=147). The EDs recorded a median of 30,000 patient contacts (n=136). Eighty-three EDs (55%) had observation units with a median of six beds. The special patient groups were pediatric patients (< 5 years) and older patients (> 75 years) with a median of 1.7% and 25%, respectively. Outpatients accounted for 55%, while 45% were admitted (intensive care unit 5.0%, standard care unit 32.3%, observation unit 6.3%) and 1.2% transferred to another hospital. CONCLUSIONS: The use of the Utstein reporting template enabled the collection of ED descriptive parameters in Germany. The data can provide a baseline for upcoming reforms on German emergency medicine, and for international comparisons on admission rates, initial triage categories, and patient populations.


Subject(s)
Clinical Observation Units , Emergency Service, Hospital , Child , Cross-Sectional Studies , Humans , Intensive Care Units , Triage
5.
Eur J Trauma Emerg Surg ; 48(1): 689-696, 2022 Feb.
Article in English | MEDLINE | ID: mdl-33025169

ABSTRACT

PURPOSE: To improve quality of trauma room management, intra- and inter-hospital benchmarking are important tools. However, primary data quality is crucial for benchmarking reliability. In this study, we analyzed the effect of a medical documentation assistant on documentation completeness in trauma room management in comparison to documentation by physicians involved in direct patient treatment. METHODS: We included all patients treated in the trauma room from 2016/01/01 to 2016/12/31 that were documented with the trauma module of the German Emergency Department Medical Record V2015.1. We divided the data into documentation by medical documentation assistant (DA, 07:00 to 17:00), physician in daytime (PD, 07:00 to 17:00), and physician at night (PN, 17:00 to 07:00). Data were analyzed for completeness (primary outcome parameter) as well as diagnostic intervals. RESULTS: There was a significant increase in complete recorded data for DA (74.5%; IQR 14.5%) compared to PD (26.9%; IQR 18.7%; p < 0.001) and PN (30.8%; IQR 18.9; p < 0.001). The time to whole-body computed tomography (WBCT) significantly decreased for DA (19 min; IQR 8.3) compared to PD (24 min; IQR 12.8; p = 0.007) or PN (24.5 min; IQR 10.0; p = 0.001). CONCLUSION: In presence of a qualified medical documentation assistant, data completeness and time to WBCT improved significantly. Therefore, utilizing a professional DA in the trauma room appears beneficial for data quality and time management.


Subject(s)
Documentation , Tomography, X-Ray Computed , Allied Health Personnel , Humans , Reproducibility of Results
6.
PLoS One ; 16(4): e0249282, 2021.
Article in English | MEDLINE | ID: mdl-33857171

ABSTRACT

Gastric carcinogenesis is associated with alterations of microRNAs (miRNAs) and reversal of these alterations may be a crucial element in cancer prevention. Here we evaluate the influence of H. pylori eradication, low-dose aspirin (LDA), non-steroidal anti-inflammatory drugs (NSAIDs) and proton-pump inhibitors (PPI) on modification of inflammatory mucosal miRNAs miR-155 and miR-223 in Helicobacter pylori-infected and non-infected subjects. The study was performed in two parts: 1) interventional study in 20 healthy subjects with and without H. pylori infection or following eradication (each n = 10) where LDA (100 mg) was given daily for 7 days; 2) prospective case-control observational study (n = 188). MiR-155 and miR-223 expression was strongly linked to H. pylori-infection and in short-term view showed a trend for reversal after eradication. Daily LDA as well as regular NSAIDs showed no influence on miRNAs expression both in healthy subjects and patients, while regular PPI intake was associated with lower miR-155 expression in antrum of patients with chronic gastritis independent of density of neutrophils and mononuclear infiltrate. In summary, PPI but not LDA or NSAIDs were associated with modification of inflammatory miRNAs miR-155 and miR-223 in an H. pylori dependent manner. The functional role of inflammatory miR-155 and miR-223 in understanding of H. pylori-related diseases needs further evaluation.


Subject(s)
Gastric Mucosa/metabolism , Helicobacter Infections/drug therapy , MicroRNAs/metabolism , Proton Pump Inhibitors/therapeutic use , Adult , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Aspirin/pharmacology , Aspirin/therapeutic use , Case-Control Studies , Cell Line , Female , Gastritis/genetics , Gastritis/pathology , Gene Expression Regulation/drug effects , Helicobacter Infections/genetics , Helicobacter Infections/microbiology , Helicobacter pylori/isolation & purification , Humans , Male , Neutrophil Infiltration , Prospective Studies , Proton Pump Inhibitors/pharmacology , Pyloric Antrum/metabolism , Young Adult
8.
Z Orthop Unfall ; 159(1): 67-74, 2021 Feb.
Article in English, German | MEDLINE | ID: mdl-31918443

ABSTRACT

BACKGROUND: Talar neck and body fractures are rare. Major posttraumatic complications with a potential reduction in the quality of life are arthrosis and necrosis due to the specific vascular supply. The aim of the study was to evaluate mid-term results of surgery for talar fractures of neck and body. Parameters that potentially affected/influenced treatment outcomes were analysed exploratively. METHODS: 24 patients with 24 talar neck and body fractures (Marti type II n = 9, type III n = 12, type IV n = 3) were retrospectively examined for radiological and clinical functional outcomes. The independent parameters evaluated included age (< 40, ≥ 40 years), sex (male, female), general overall extent of injury (polytrauma/multiple injuries/multiple fractures of the extremities, additional injuries to the same foot, isolated talus fracture), soft tissue damage (open, closed), surgical latency (< 6, ≥ 6 h), fracture classification/displacement (undisplaced [= Marti II], displaced [= Marti III, IV]) and fracture type (talar body, neck fracture). The potential influencing parameters were analysed by univariate analyses. RESULTS: With an average follow-up of 8.7 years (1,25 - 16 years) the AOFAS score was 71.4 ± 22.9 points, the Foot Function Index score 35.9 ± 28.3 points; the physical and mental component summary scores of the Short Form 36, version 2, was 43.8 ± 10.9 and 47.4 ± 13.6 points (mean ± standard deviation), respectively. Thus, the patient reported physical health of the patients was slightly reduced compared to the German population, while the mental health remained largely unaffected. Two patients developed partial avascular necrosis (8%), 10 patients developed osteoarthritis (42%). Of the independent parameters, only the general overall extent of injury showed a significant influence on osteoarthritis (p = 0.002). In the evaluation of undisplaced (n = 9) and displaced (n = 15) fractures, surgical treatment after more than 6 hours did not result in a worse outcome. CONCLUSION: The clinical outcome of internal fixation of talar neck and body fractures can be classified as good. In the study group, there was no correlation between the occurrence of arthrosis and the Marti fracture classification.


Subject(s)
Ankle Fractures , Fracture Fixation, Internal , Fractures, Bone , Talus , Adult , Ankle Fractures/diagnostic imaging , Ankle Fractures/surgery , Female , Fracture Fixation, Internal/adverse effects , Fracture Fixation, Internal/methods , Fractures, Bone/classification , Fractures, Bone/diagnostic imaging , Fractures, Bone/surgery , Humans , Male , Necrosis/etiology , Osteoarthritis/etiology , Quality of Life , Retrospective Studies , Talus/blood supply , Talus/diagnostic imaging , Talus/injuries , Talus/surgery , Treatment Outcome
9.
Med Klin Intensivmed Notfmed ; 116(1): 50-55, 2021 Feb.
Article in English | MEDLINE | ID: mdl-31811310

ABSTRACT

BACKGROUND: In recent years, increases in the number of patients in emergency departments (ED) have led to continuous work intensification. To handle this problem, the treatment effectiveness has to be maximized. One strategy that may help to optimize workflow is the use of standard operating procedures (SOPs). We investigated the existence of SOPs and subjective effects on treatment in German EDs. METHODS: We performed an online survey from February 2015 until June 2016. We collected data regarding the existence of SOPs, health care level, medical field, work experience, and education. All professional groups participating in the treatment of patients were requested to take part in the survey. RESULTS: Seventy-five percent of the 589 participants in the survey confirmed the existence of SOPs in their EDs. SOPs were more frequently available in hospitals with higher health care levels. Participants working in EDs without SOPs felt less confident regarding treatment of patients. More than 85% of these participants were in favor of having SOPs. The absence of SOPs was associated with a subjective delay in patient treatment. CONCLUSION: Most of the EDs had available SOPs. In departments without SOPs, most physicians wanted them to be implemented. SOPs seemed adequate in terms of supporting workflow and satisfaction with patients' treatment.


Subject(s)
Emergency Service, Hospital , Physicians , Humans , Reference Standards , Surveys and Questionnaires
10.
BMJ Open ; 10(9): e038776, 2020 09 17.
Article in English | MEDLINE | ID: mdl-32948571

ABSTRACT

INTRODUCTION: Quality of emergency department (ED) care affects patient outcomes substantially. Quality indicators (QIs) for ED care are a major challenge due to the heterogeneity of patient populations, health care structures and processes in Germany. Although a number of quality measures are already in use, there is a paucity of data on the importance of these QIs on medium-term and long-term outcomes. The evaluation of outcome relevance of quality indicators in the emergency department study (ENQuIRE) aims to identify and investigate the relevance of QIs in the ED on patient outcomes in a 12-month follow-up. METHODS AND ANALYSIS: The study is a prospective non-interventional multicentre cohort study conducted in 15 EDs throughout Germany. Included are all patients in 2019, who were ≥18 years of age, insured at the Techniker Krankenkasse (statutory health insurance (SHI)) and gave their written informed consent to the study.The primary objective of the study is to assess the effect of selected quality measures on patient outcome. The data collected for this purpose comprise medical records from the ED treatment, discharge (claims) data from hospitalised patients, a patient questionnaire to be answered 6-8 weeks after emergency admission, and outcome measures in a 12-month follow-up obtained as claims data from the SHI.Descriptive and analytical statistics will be applied to provide summaries about the characteristics of QIs and associations between quality measures and patient outcomes. ETHICS AND DISSEMINATION: Approval of the leading ethics committee at the Medical Faculty of the University of Magdeburg (reference number 163/18 from 19 November 2018) has been obtained and adapted by responsible local ethics committees.The findings of this work will be disseminated by publication of peer-reviewed manuscripts and presentations as conference contributions (abstracts, poster or oral presentations).Moreover, results will be discussed with clinical experts and medical associations before being proposed for implementation into the quality management of EDs. TRIAL REGISTRATION NUMBER: German Clinical Trials Registry (DRKS00015203); Pre-results.


Subject(s)
Emergency Service, Hospital , Quality Indicators, Health Care , Cohort Studies , Germany , Humans , Multicenter Studies as Topic , Prospective Studies
11.
Stud Health Technol Inform ; 267: 238-246, 2019 Sep 03.
Article in English | MEDLINE | ID: mdl-31483278

ABSTRACT

The German Emergency Department Data Registry (GEDD-registry, AKTIN) provides an infrastructure for collecting and querying up-to-date medical records in a distributed manner. Within this framework, a benchmark report on cross-institutional comparison using the program R is prepared using routine data of participating hospitals. Currently, 16 emergency departments (EDs) routinely transfer data of 1,200 to approximately 5,000 patients per month to a federated GEDD-registry datawarehouse. Using various packages in the R environment, hospitals receive a monthly visual report on their data among all participating hospitals. Graphical representations are implemented using column diagrams and box plots. Reports currently contain 25 tables and 40 graphs. Benchmark reports are created in R-Studio and exported using Portable Document Format, PDF. Quarterly expert meetings with the heads of participating EDs are currently performed for further improvements. Preparation of external benchmarking reports with R enables a detailed data presentation for participating hospitals and ED managers.


Subject(s)
Benchmarking , Emergency Service, Hospital , Hospitals , Humans , Registries
12.
BMC Health Serv Res ; 19(1): 558, 2019 Aug 09.
Article in English | MEDLINE | ID: mdl-31399096

ABSTRACT

BACKGROUND: Some of the advantages of implementing electronic emergency department information systems (EDIS) are improvements in data availability and simplification of statistical evaluations of emergency department (ED) treatments. However, for multi-center evaluations, standardized documentation is necessary. The AKTIN project ("National Emergency Department Register: Improvement of Health Services Research in Acute Medicine in Germany") has used the "German Emergency Department Medical Record" (GEDMR) published by the German Interdisciplinary Association of Intensive and Emergency Care as the documentation standard for its national data registry. METHODS: Until March 2016 the documentation standard in ED was the pen-and-paper version of the GEDMR. In April 2016 we implemented the GEDMR in a timeline-based EDIS. Related to this, we compared the availability of structured treatment information of traumatological patients between pen-and-paper-based and electronic documentation, with special focus on the treatment time. RESULTS: All 796 data fields of the 6 modules (basic data, severe trauma, patient surveillance, anesthesia, council, neurology) were adapted for use with the existing EDIS configuration by a physician working regularly in the ED. Electronic implementation increased availability of structured anamnesis and treatment information. However, treatment time was increased in electronic documentation both immediately (2:12 ± 0:04 h; n = 2907) and 6 months after implementation (2:18 ± 0:03 h; n = 4778) compared to the pen-and-paper group (1:43 ± 0:02 h; n = 2523; p < 0.001). CONCLUSIONS: We successfully implemented standardized documentation in an EDIS. The availability of structured treatment information was improved, but treatment time was also increased. Thus, further work is necessary to improve input time.


Subject(s)
Documentation/statistics & numerical data , Electronic Health Records/organization & administration , Emergency Service, Hospital/organization & administration , Registries/statistics & numerical data , Electronic Health Records/statistics & numerical data , Germany , Humans , Male , Retrospective Studies
13.
Unfallchirurg ; 122(3): 243-246, 2019 Mar.
Article in German | MEDLINE | ID: mdl-30666344

ABSTRACT

Digitalization and standardization of documentation in medicine are increasingly progressing. In the decision of the Federal Joint Committee (G-BA) for a staged system of emergency structures in hospitals and in the report of the expert committee for development in the healthcare system on needs-oriented guidance of healthcare, the actuality of the topic is underlined with concrete naming of future tasks. The section on emergency admission protocols of the German Interdisciplinary Association of Intensive and Emergency Care Medicine (DIVI) has been working for years on this topic and has repeatedly reported on the progress of the topic in clinical emergency care. Standardization and digitalization represent the foundation for health services research spread across locations as well as the possibility for benchmarking. Digitalization makes the secondary use of primary clinical routine data possible. Digitalization decreases redundancies of data transmission by avoiding manual data input in, for example registers.


Subject(s)
Emergency Medical Services , Emergency Medicine , Documentation , Hospitals
14.
World J Gastroenterol ; 23(26): 4712-4723, 2017 Jul 14.
Article in English | MEDLINE | ID: mdl-28765692

ABSTRACT

AIM: To evaluate the frequency of Helicobacter pylori (H. pylori) CagA antibodies in H. pylori infected subjects and to identify potential histopathological and bacterial factors related to H. pylori CagA-immune response. METHODS: Systematic data to H. pylori isolates, blood samples, gastric biopsies for histological and molecular analyses were available from 99 prospectively recruited subjects. Serological profile (anti-H. pylori, anti-CagA) was correlated with H. pylori isolates (cagA, EPIYA, vacA s/m genotype), histology (Sydney classification) and mucosal interleukin-8 (IL-8) mRNA and protein expression. Selected H. pylori strains were assessed for H. pylori CagA protein expression and IL-8 induction in co-cultivation model with AGS cells. RESULTS: Thirty point three percent of microbiologically confirmed H. pylori infected patients were seropositive for CagA. Majority of H. pylori isolates were cagA gene positive (93.9%) with following vacA polymorphisms: 42.4% vacA s1m1, 23.2% s1m2 and 34.3% s2m2. Anti-CagA-IgG seropositivity was strongly associated with atrophic gastritis, increased mucosal inflammation according to the Sydney score, IL-8 and cagA mRNA expression. VacA s and m polymorphisms were the major determinants for positive (vacA s1m1) or negative (vacA s2m2) anti-CagA serological immune response, which also correlated with the in vitro inflammatory potential in AGS cells. In vitro co-cultivation of representative H. pylori strains with AGS cells confirmed functional CagA translocation, which showed only partial correlation with CagA seropositivity in patients, supporting vacA as major co-determinant of the immune response. CONCLUSION: Serological immune response to H. pylori cagA+ strain in H. pylori infected patients is strongly associated with vacA polymorphism, suggesting the crucial role of bacterial factors in immune and clinical phenotype of the infection.


Subject(s)
Antigens, Bacterial/immunology , Bacterial Proteins/immunology , Helicobacter Infections/immunology , Helicobacter pylori/immunology , Adult , Aged , Female , Helicobacter pylori/genetics , Humans , Male , Middle Aged , Prospective Studies
15.
Sci Rep ; 5: 8270, 2015 Feb 05.
Article in English | MEDLINE | ID: mdl-25652892

ABSTRACT

Gastric carcinogenesis is a multifactorial H.pylori-triggered dynamic process that goes through a cascade of preneoplastic conditions. The expression of miRNAs in the stomach with regard to preneoplastic precursor conditions and H.pylori infection has not been investigated systematically. In this prospective proof-of-principle study, we evaluated the miRNA expression in gastric antrum and corpus mucosa from patients with chronic non-atrophic gastritis (CNAG), atrophic gastritis (AG), and GC compared to controls. Gastric normal mucosa shows a unique expression pattern for miR-21, miR-155 and miR-223, which is specific for different regions. In correlation with progression of Correa's cascade and H.pylori infection, we observed a gradual increase in miR-155 and miR-223 both in corpus and antrum and miR-21 only in the antrum mucosa. Using miRNA expression we calculated a score that allowed us to discriminate patients with AG from subjects with normal mucosa with high diagnostic accuracy in testing and validation cohorts reproducibly. In summary, the expression pattern of miRNAs in the gastric mucosa is gradually increased with progression of Correa's cascade and H.pylori infection, suggesting miRNAs as potential biomarkers for preneoplastic precursor conditions. However, differences of miRNA expression between the gastric antrum and the corpus need to be considered in future studies.


Subject(s)
Gastric Mucosa/metabolism , Gastric Mucosa/pathology , Gene Expression Regulation , MicroRNAs/genetics , Precancerous Conditions/genetics , Precancerous Conditions/pathology , Adult , Aged , Aged, 80 and over , Biopsy , Female , Gastritis, Atrophic/genetics , Gastritis, Atrophic/pathology , Gene Expression Profiling , Helicobacter Infections , Helicobacter pylori , Humans , Male , Middle Aged , Precancerous Conditions/etiology , Prospective Studies , Pyloric Antrum/metabolism , Pyloric Antrum/pathology , Reproducibility of Results , Stomach Neoplasms/etiology , Stomach Neoplasms/pathology
16.
Gastroenterology ; 142(4): 947-956.e5, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22240481

ABSTRACT

BACKGROUND & AIMS: Wilson disease is a severe disorder of copper metabolism caused by mutations in ATP7B, which encodes a copper-transporting adenosine triphosphatase. The disease presents with a variable phenotype that complicates the diagnostic process and treatment. Little is known about the mechanisms that contribute to the different phenotypes of the disease. METHODS: We analyzed 28 variants of ATP7B from patients with Wilson disease that affected different functional domains; the gene products were expressed using the baculovirus expression system in Sf9 cells. Protein function was analyzed by measuring catalytic activity and copper ((64)Cu) transport into vesicles. We studied intracellular localization of variants of ATP7B that had measurable transport activities and were tagged with green fluorescent protein in mammalian cells using confocal laser scanning microscopy. RESULTS: Properties of ATP7B variants with pathogenic amino-acid substitution varied greatly even if substitutions were in the same functional domain. Some variants had complete loss of catalytic and transport activity, whereas others lost transport activity but retained phosphor-intermediate formation or had partial losses of activity. In mammalian cells, transport-competent variants differed in stability and subcellular localization. CONCLUSIONS: Variants in ATP7B associated with Wilson disease disrupt the protein's transport activity, result in its mislocalization, and reduce its stability. Single assays are insufficient to accurately predict the effects of ATP7B variants the function of its product and development of Wilson disease. These findings will contribute to our understanding of genotype-phenotype correlation and mechanisms of disease pathogenesis.


Subject(s)
Adenosine Triphosphatases/metabolism , Cation Transport Proteins/metabolism , Hepatolenticular Degeneration/enzymology , Adenosine Triphosphatases/genetics , Adenosine Triphosphate/metabolism , Baculoviridae/enzymology , Baculoviridae/genetics , Catalytic Domain , Cation Transport Proteins/genetics , Copper/metabolism , Copper-Transporting ATPases , Enzyme Stability , Genetic Predisposition to Disease , Genetic Vectors , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , HEK293 Cells , Hepatolenticular Degeneration/genetics , Humans , Ion Transport , Kinetics , Microscopy, Confocal , Models, Molecular , Mutation , Phenotype , Phosphorylation , Protein Conformation , Protein Transport , Recombinant Fusion Proteins/metabolism , Structure-Activity Relationship , Transfection
17.
J Biol Chem ; 285(40): 30875-83, 2010 Oct 01.
Article in English | MEDLINE | ID: mdl-20647314

ABSTRACT

Wilson disease (WD) is a severe hepato-neurologic disorder that affects primarily children and young adults. WD is caused by mutations in ATP7B and subsequent copper overload. However, copper levels alone do not predict severity of the disease. We demonstrate that temporal and spatial distribution of copper in hepatocytes may play an important role in WD pathology. High resolution synchrotron-based x-ray fluorescence imaging in situ indicates that copper does not continuously accumulate in Atp7b(-/-) hepatocytes, but reaches a limit at 90-300 fmol. The lack of further accumulation is associated with the loss of copper transporter Ctr1 from the plasma membrane and the appearance of copper-loaded lymphocytes and extracellular copper deposits. The WD progression is characterized by changes in subcellular copper localization and transcriptome remodeling. The synchrotron-based x-ray fluorescence imaging and mRNA profiling both point to the key role of nucleus in the initial response to copper overload and suggest time-dependent sequestration of copper in deposits as a protective mechanism. The metabolic pathways, up-regulated in response to copper, show compartmentalization that parallels changes in subcellular copper concentration. In contrast, significant down-regulation of lipid metabolism is observed at all stages of WD irrespective of copper distribution. These observations suggest new stage-specific as well as general biomarkers for WD. The model for the dynamic role of copper in WD is proposed.


Subject(s)
Adenosine Triphosphatases/metabolism , Cation Transport Proteins/metabolism , Cell Membrane/metabolism , Copper/metabolism , Hepatocytes/metabolism , Hepatolenticular Degeneration/metabolism , Adenosine Triphosphatases/genetics , Adult , Animals , Biomarkers/metabolism , Cation Transport Proteins/genetics , Cell Membrane/genetics , Cell Membrane/pathology , Child , Child, Preschool , Copper Transporter 1 , Copper-Transporting ATPases , Disease Models, Animal , Hepatocytes/pathology , Hepatolenticular Degeneration/genetics , Hepatolenticular Degeneration/pathology , Humans , Lipid Metabolism/genetics , Lymphocytes/metabolism , Lymphocytes/pathology , Mice , Mice, Knockout
18.
Exp Cell Res ; 315(20): 3500-8, 2009 Dec 10.
Article in English | MEDLINE | ID: mdl-19665015

ABSTRACT

Helicobacter pylori, a microaerophilic gram-negative bacterium, colonizes the human stomach. About 50% of the world's population is infected, and this infection is considered as the major risk factor for the development of gastric adenocarcinomas in 1% of infected subjects. Carcinogenesis is characterized by the process of epithelial-to-mesenchymal transition (EMT), in the course of which fully differentiated epithelial cells turn into depolarized and migratory cells. Concomitant disruption of adherence junctions (AJ) is facilitated by growth factors like hepatocyte growth factor 1 (HGF-1), but has been also shown to depend on ectodomain shedding of E-cadherin. The aim of this study was to investigate the impact of infection with H. pylori of NCI-N87 gastric epithelial cells on the shedding of E-cadherin and HGF-receptor c-Met. Our results show that infection with H. pylori provokes shedding of the surface proteins c-Met and E-cadherin. Evidence is provided that ADAM10 contributes to the shedding of c-Met and E-cadherin.


Subject(s)
Cadherins/metabolism , Epithelial Cells/metabolism , Epithelial Cells/microbiology , Helicobacter Infections/metabolism , Helicobacter pylori/physiology , Peptide Fragments/metabolism , Proto-Oncogene Proteins c-met/metabolism , ADAM Proteins/genetics , ADAM Proteins/metabolism , ADAM10 Protein , Amyloid Precursor Protein Secretases/genetics , Amyloid Precursor Protein Secretases/metabolism , Cell Line , Disease Progression , Gene Expression/genetics , Glycine/analogs & derivatives , Glycine/pharmacology , Helicobacter Infections/microbiology , Humans , Hydroxamic Acids/pharmacology , Membrane Proteins/genetics , Membrane Proteins/metabolism , Metalloendopeptidases/antagonists & inhibitors , Metalloendopeptidases/metabolism , Protease Inhibitors/pharmacology , RNA, Small Interfering/genetics , Stomach/cytology , Stomach Neoplasms/metabolism , Stomach Neoplasms/microbiology , Stomach Neoplasms/pathology , Transfection
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