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1.
Anaesthesist ; 69(3): 162-169, 2020 03.
Article in German | MEDLINE | ID: mdl-32055886

ABSTRACT

BACKGROUND: Besides public awareness and specialist knowledge and training of physicians, their self-confidence plays a key role for clinical decision-making in the respective area. OBJECTIVE: This exploratory study investigated the influence of the discipline on differences in self-confidence in dealing with antibiotics and in the self-rated knowledge. METHODS: In 2015 the multi-institutional reconnaissance of practice with multiresistant bacteria (MR2) questionnaire containing items on antibiotic prescription and multiresistant pathogens was sent out to 1061 physicians working in departments for internal medicine, general surgery, gynecology and obstetrics and urology. In 2017 a similar MR2 survey was sent to 1268 specialist and assistant physicians in anesthesiology in Germany. Besides demographic data 4 items on self-confidence in the use of antibiotic treatment and 11 items concerning self-rated knowledge about rational antibiotic therapy and multiresistant pathogens were included in the present analysis. Logistic regression analysis, the χ2-test and the Kruskal-Wallis test were used for statistical analysis of the influence of the discipline on these items. RESULTS: The response rates were 43% (456 out of 1061) from the non-anesthetists and 56% (705 out of 1268) from the anesthetists. Of the non-anesthetists 44% and 57% of the anesthetists had had no advanced training on antibiotic stewardship during the year before the study. In the overall analysis anesthetists (mean±SD: 2.53±0.54) were significantly less self-confident about antibiotics than colleagues from other departments (internal medicine: 3.10±0.50, general surgery: 2.97±0.44, gynecology and obstetrics: 3.12±0.42 and urology: 3.15±0.44) in the unadjusted (all p<0.001) and adjusted comparison. The analysis of self-rated knowledge about rational antibiotic prescription showed similar results. Senior consultant status and advanced training in infectiology were significantly associated with self-confidence and self-rated knowledge about antibiotics. CONCLUSION: Anesthetists showed significantly less self-confidence in dealing with antibiotics than colleagues from other disciplines. Advanced training on a rational prescription of antibiotics was associated with a greater self-confidence, so that the implementation of compulsory courses on rational antibiotic stewardship in the respective residency curriculum needs to be considered.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Physicians/statistics & numerical data , Specialization/statistics & numerical data , Anesthesiologists/statistics & numerical data , Attitude of Health Personnel , Germany , Hospitals , Humans , Prescriptions , Self Concept , Surveys and Questionnaires
2.
Ann Oncol ; 29(5): 1286-1291, 2018 05 01.
Article in English | MEDLINE | ID: mdl-29509837

ABSTRACT

Background: Hepatocellular carcinomas (HCCs) are not routinely biopsied, resulting in a lack of tumor materials for molecular profiling. Here we sought to determine whether plasma-derived cell-free DNA (cfDNA) captures the genetic alterations of HCC in patients who have not undergone systemic therapy. Patients and methods: Frozen biopsies from the primary tumor and plasma were synchronously collected from 30 prospectively recruited, systemic treatment-naïve HCC patients. Deep sequencing of the DNA from the biopsies, plasma-derived cfDNA and matched germline was carried out using a panel targeting 46 coding and non-coding genes frequently altered in HCCs. Results: In 26/30 patients, at least one somatic mutation was detected in biopsy and/or cfDNA. Somatic mutations in HCC-associated genes were present in the cfDNA of 63% (19/30) of the patients and could be detected 'de novo' without prior knowledge of the mutations present in the biopsy in 27% (8/30) of the patients. Mutational load and the variant allele fraction of the mutations detected in the cfDNA positively correlated with tumor size and Edmondson grade. Crucially, among the seven patients in whom the largest tumor was ≥5 cm or was associated with metastasis, at least one mutation was detected 'de novo' in the cfDNA of 86% (6/7) of the cases. In these patients, cfDNA and tumor DNA captured 87% (80/92) and 95% (87/92) of the mutations, suggesting that cfDNA and tumor DNA captured similar proportions of somatic mutations. Conclusion: In patients with high disease burden, the use of cfDNA for genetic profiling when biopsy is unavailable may be feasible. Our results support further investigations into the clinical utility of cfDNA in a larger cohort of patients.


Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Hepatocellular/genetics , Circulating Tumor DNA/genetics , Liver Neoplasms/genetics , Aged , Aged, 80 and over , Biomarkers, Tumor/blood , Biopsy/methods , Carcinoma, Hepatocellular/blood , Carcinoma, Hepatocellular/pathology , Circulating Tumor DNA/blood , DNA Mutational Analysis/methods , Feasibility Studies , Female , High-Throughput Nucleotide Sequencing , Humans , Liver/pathology , Liver Neoplasms/blood , Liver Neoplasms/pathology , Male , Middle Aged , Mutation , Pilot Projects , Tumor Burden/genetics
3.
J Viral Hepat ; 25(3): 262-271, 2018 03.
Article in English | MEDLINE | ID: mdl-29086446

ABSTRACT

Steatosis is a frequent histological feature of hepatitis C virus (HCV) infection. Cohort studies of patients with chronic hepatitis C identified HCV genotype 3 (HCV GT3) as the prevalent steatotic genotype. Moreover, Huh-7 cells over-expressing HCV GT3 core protein accumulate more triglyceride in larger lipid droplets than cells expressing core proteins of other HCV genotypes. However, little is known about the relationship of steatosis and HCV infection at the cellular level in vivo. In this study, we used highly sensitive multiplex in situ hybridization methodology together with lipid staining to investigate HCV-induced lipid droplet accumulation at the cellular level in liver biopsies. Consistent with previous reports, histological steatosis grades were significantly higher in GT3 compared to GT1 infected livers, but independent of viral load. Using nile red lipid stainings, we observed that the frequency of lipid droplet containing cells was similar in HCV GT1- and HCV GT3-infected livers. Lipid droplet formation preferentially occurred in HCV-infected cells irrespective of the genotype, but was also observed in noninfected cells. These findings demonstrate that the main difference between GT1- and GT3-induced steatosis is the size of lipid droplets, but not the number or relative distribution of lipid droplets in infected vs uninfected hepatocytes.


Subject(s)
Fatty Liver/pathology , Genotype , Hepacivirus/classification , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/virology , Biopsy , Hepacivirus/genetics , Hepacivirus/isolation & purification , Histocytochemistry , Humans , Lipid Droplets/pathology , Liver/pathology
4.
J Viral Hepat ; 25(8): 920-929, 2018 08.
Article in English | MEDLINE | ID: mdl-29532619

ABSTRACT

It remains unclear whether hepatitis B virus (HBV) infection may modify the severity of viral steatosis in patients coinfected with chronic hepatitis C virus (HCV). We examined the influence of coinfection with HBV on prevalence of steatosis in chronic hepatitis C in a multi-centre cohort of HBV-HCV subjects, and by performing a systematic review and meta-analysis of the literature. We centrally and blindly assessed steatosis prevalence and severity in a cohort of HBV-HCV coinfected subjects compared to HCV and HBV monoinfected controls and we performed a systematic review of studies addressing the prevalence of steatosis in HBV-HCV subjects compared to HCV controls. In the clinical cohort, we included 85 HBV-HCV, 69 HBV and 112 HCV subjects from 16 international centres. There was no significant difference in steatosis prevalence between the HBV-HCV and the HCV groups (33% vs 45%, P = .11). In subgroup analysis, lean HBV-HCV subjects with detectable HBV DNA had less steatosis than lean HCV subjects matched for HCV viremia (15% vs 45%, P = .02). Our literature search identified 5 additional studies included in a systematic review. Overall, prevalence of steatosis > 5% was similar in HBV-HCV infection compared to HCV (pooled odds ratio [OR] 0.91, 95% CI 0.53-1.6) although there was significant heterogeneity (I2 69%, P = .007). In conclusion, although the prevalence of steatosis is similar in HBV-HCV compared to HCV subjects, our analysis suggests that there may be an inhibitory effect of HCV-induced steatogenesis by HBV in certain subgroups of patients.


Subject(s)
Coinfection/complications , Fatty Liver/epidemiology , Fatty Liver/pathology , Hepatitis B, Chronic/complications , Hepatitis C, Chronic/complications , Adult , Female , Humans , Male , Middle Aged , Prevalence , Retrospective Studies
5.
J Viral Hepat ; 24(8): 662-671, 2017 08.
Article in English | MEDLINE | ID: mdl-28182305

ABSTRACT

Current treatment options for patients with chronic hepatitis B virus (HBV) infection are not curative as they are not effective in eliminating covalently closed circular DNA (cccDNA). cccDNA is a stable template for HBV transcription in the nucleus of hepatocytes and is thought to be one of the main factors responsible for HBV persistence. Recently, activation of the lymphotoxin beta receptor (LTßR) has been shown to trigger degradation of cccDNA through induction of cytidine deaminases of the APOBEC3 family in HBV cell culture model systems. To assess the presence and relevance of such mechanisms in the liver of chronically HBV-infected patients, we compared intrahepatic cccDNA levels with the expression levels of lymphotoxins and some of their target genes (eg APOBEC deaminases) in liver biopsy tissue. Our results confirm elevated gene expression levels of components of the lymphotoxin pathway including lymphotoxin alpha (LTα), lymphotoxin beta (LTß), APOBEC3B (A3B) and APOBEC3G (A3G) in the chronically HBV-infected liver compared to uninfected liver. Furthermore, expression levels of the genes of the APOBEC deaminase family were correlated with those of LTα and LTß gene expression, consistent with lymphotoxin-mediated upregulation of APOBEC gene expression. However, intrahepatic cccDNA and HBV replication levels were not correlated with LTα, LTß and APOBEC gene expression. In conclusion, these results suggest that although the lymphotoxin pathway is activated in the chronically HBV-infected liver, it has no major impact on HBV cccDNA metabolism in chronic HBV infection.


Subject(s)
DNA, Circular/analysis , Hepatitis B virus/growth & development , Hepatitis B, Chronic/pathology , Hepatitis B, Chronic/virology , Homeostasis , Lymphotoxin beta Receptor/metabolism , Lymphotoxin-alpha/metabolism , Cytidine Deaminase/metabolism , Gene Expression Profiling , Hepatitis B virus/immunology , Hepatitis B, Chronic/immunology , Humans
6.
Zentralbl Chir ; 141(1): 22-30, 2016 Feb.
Article in German | MEDLINE | ID: mdl-24022244

ABSTRACT

By the optimised availability of less expensive and safe red cell packs and other blood products over the last 20 years, numerous surgical interventions have become possible without any demand for comments on the precise need. However, a number of publications indicates that blood transfusion may also induce disadvantageous effects on the postoperative course by immunomodulation, which requires a rather restrictive indication for transfusion. Furthermore, demographic development leads to a decrease in that portion of the population with the potential for blood donation accompanied simultaneously by an increase of the percentage of older patients with more need of blood products during medical treatment. This makes blood-sparing measures necessary. In addition, costs for red cell packs have increased, in particular, for the generally compatible blood group 0 - an extra amount for rhesus negative blood. The present narrative review highlights, therefore, important news from the clinical transfusion medicine, immunohaematology and haemostaseology and their impact on daily transfusion practice. In this context, "blood management" is considered as one of the very effective blood-sparing measures, which focusses especially i) on the substitution of iron in case of depressed preoperative haemoglobin as well as ii) to elucidate disorders of coagulation by structured medical history and, subsequently, to balance possible need by a specific plan for substitution. Simultaneously, prospective studies are initiated to investigate how far the transfusion trigger of a patient can be lowered down to a still appropriate level. As far as consolidated findings are already available, they are described with regard to the single blood components and taking into account the cross-sectional guidelines of the "Bundesärztekammer" (Federal Physicians Chamber). Finally, initial evidence is provided characterising patient- and blood donor-specific, blood group-dependent features of a reasonable haemotherapy.


Subject(s)
Blood Component Transfusion/methods , Blood Transfusion/methods , Intraoperative Care/methods , Perioperative Care/methods , Blood Coagulation Factors/therapeutic use , Blood Transfusion, Autologous/methods , Evidence-Based Medicine , Humans , Plasma Substitutes
7.
Gut ; 64(10): 1605-15, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25214320

ABSTRACT

OBJECTIVE: The natural course of chronic hepatitis C varies widely. To improve the profiling of patients at risk of developing advanced liver disease, we assessed the relative contribution of factors for liver fibrosis progression in hepatitis C. DESIGN: We analysed 1461 patients with chronic hepatitis C with an estimated date of infection and at least one liver biopsy. Risk factors for accelerated fibrosis progression rate (FPR), defined as ≥ 0.13 Metavir fibrosis units per year, were identified by logistic regression. Examined factors included age at infection, sex, route of infection, HCV genotype, body mass index (BMI), significant alcohol drinking (≥ 20 g/day for ≥ 5 years), HIV coinfection and diabetes. In a subgroup of 575 patients, we assessed the impact of single nucleotide polymorphisms previously associated with fibrosis progression in genome-wide association studies. Results were expressed as attributable fraction (AF) of risk for accelerated FPR. RESULTS: Age at infection (AF 28.7%), sex (AF 8.2%), route of infection (AF 16.5%) and HCV genotype (AF 7.9%) contributed to accelerated FPR in the Swiss Hepatitis C Cohort Study, whereas significant alcohol drinking, anti-HIV, diabetes and BMI did not. In genotyped patients, variants at rs9380516 (TULP1), rs738409 (PNPLA3), rs4374383 (MERTK) (AF 19.2%) and rs910049 (major histocompatibility complex region) significantly added to the risk of accelerated FPR. Results were replicated in three additional independent cohorts, and a meta-analysis confirmed the role of age at infection, sex, route of infection, HCV genotype, rs738409, rs4374383 and rs910049 in accelerating FPR. CONCLUSIONS: Most factors accelerating liver fibrosis progression in chronic hepatitis C are unmodifiable.


Subject(s)
Hepacivirus/genetics , Hepatitis C, Chronic/complications , Liver Cirrhosis/etiology , Polymorphism, Single Nucleotide , RNA, Viral/analysis , Risk Assessment/methods , Biopsy , Disease Progression , Female , Genome-Wide Association Study , Hepatitis C, Chronic/virology , Humans , Incidence , Liver Cirrhosis/diagnosis , Liver Cirrhosis/epidemiology , Male , Retrospective Studies , Risk Factors , Switzerland/epidemiology , Time Factors
8.
J Viral Hepat ; 21(1): 9-18, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24329853

ABSTRACT

The maintenance of glucose homeostasis is a complex process in which the insulin signalling pathway plays a major role. Disruption of insulin-regulated glucose homeostasis is frequently observed in chronic hepatitis C (CHC) infection and might potentially contribute to type 2 diabetes mellitus (T2DM) development. Presently, the mechanism that links HCV infection to insulin resistance remains unclear. Previously, we have reported that HCV protein expression in HCV transgenic mice (B6HCV) leads to an overexpression of protein phosphatase 2A (PP2A) through an ER stress response. In the present work, we describe an association of FoxO1 hypophosphorylation and upregulation of both PGC-1α and G6Pase to phenotypic hyperglycaemia and insulin resistance in B6HCV mice. In vitro, we observed that PGC1α is concomitantly induced with PP2A. Moreover, we show that the enhanced PP2A expression is sufficient to inhibit insulin-induced FoxO1 phosphorylation via blockade of insulin-mediated Akt activation or/and through direct association and dephosphorylation of pS-FoxO1. Consequently, we found that the gluconeogenic gene glucose-6-phosphatase is upregulated. These observations were confirmed in liver biopsies obtained from CHC patients. In summary, our results show that HCV-mediated upregulation of PP2A catalytic subunit alters signalling pathways that control hepatic glucose homeostasis by inhibiting Akt and dephosphorylation of FoxO1.


Subject(s)
Forkhead Transcription Factors/metabolism , Glucose/metabolism , Hepatitis C, Chronic/pathology , Homeostasis , Protein Phosphatase 2/metabolism , Transcription Factors/metabolism , Animals , Biopsy , Disease Models, Animal , Forkhead Box Protein O1 , Glucose-6-Phosphatase/metabolism , Humans , Insulin Resistance , Mice , Mice, Inbred C57BL , Mice, Transgenic , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha
9.
J Eur Acad Dermatol Venereol ; 28(6): 771-80, 2014 Jun.
Article in English | MEDLINE | ID: mdl-23651052

ABSTRACT

BACKGROUND: Skin blistering diseases due to autoantibodies are typically treated with high dose systemic corticosteroids and other conventional immunosuppressants. However, in severe cases, this treatment may not be sufficient to achieve disease control or contraindicated because of comorbidity. METHODS: We describe 15 patients (pts.) with such diseases: 6 pts. with pemphigus vulgaris, 3 pts. with bullous pemphigoid, 3 pts. with mucous membrane pemphigoid (MMP), one being anti-laminin-332-MMP (AL332-MMP), 2 pts. with pemphigus foliaceus and 1 pt. with epidermolysis bullosa acquisita (EBA). Patients were treated with a combination of protein A immunoadsorption (PAIA, 3-21 treatments) and rituximab (3-6 treatments) in addition to low dose conventional immunosuppression. RESULTS: All patients showed rapid clinical improvement starting within the first 4 weeks and decline of circulating autoantibody levels. Complete/partial remission was 88%/12% in pemphigus and 71%/29% in subepidermal blistering diseases. Overall relapse rate was 13% with an average follow-up of 22 months. In the AL332-MMP pt. the PAIA/rituximab treatment was stopped because of an oesophagus cancer considered as the paraneoplastic cause of the skin disease. CONCLUSION: Combined treatment with PAIA and rituximab showed rapid and long-lasting response, thereby allowing substantial reduction of dosage of concomitant immunosuppressive medication. We hereby confirm data from other investigators that PAIA/rituximab treatment is a promising therapeutical modality for pemphigus, pemphigoids and EBA, characterized by a favourable ratio of beneficial efficacy and minimized long-term adverse effects.


Subject(s)
Antibodies, Monoclonal, Murine-Derived/administration & dosage , Autoimmune Diseases/therapy , Immunologic Factors/administration & dosage , Immunosuppressive Agents/administration & dosage , Skin Diseases, Vesiculobullous/immunology , Skin Diseases, Vesiculobullous/therapy , Sorption Detoxification , Aged , Aged, 80 and over , Clinical Protocols , Combined Modality Therapy , Female , Humans , Immunosorbent Techniques , Male , Middle Aged , Pulse Therapy, Drug , Retrospective Studies , Rituximab , Severity of Illness Index , Staphylococcal Protein A
10.
Laryngorhinootologie ; 92(11): 737-45, 2013 Nov.
Article in German | MEDLINE | ID: mdl-23709161

ABSTRACT

BACKGROUND: Aim of this study was to find out how many patients after a total laryngectomy (TLE) return to work successfully and what factors support vocational rehabilitation. PATIENTS AND METHODS: Laryngectomees (n=231) aged up to 60 years completed questionnaires and structured interviews before TLE (t1), before rehabilitation (t2), at the end of rehabilitation (t3), 1 year after TLE (t4), 2 years after TLE (t5), and 3 years after TLE (t6). RESULTS: Prior to TLE, 38% of all respondents were employed, 34% were unemployed, 23% received disability-related and 3% age-related pension retirement. One year after TLE, 13% were employed, 15% 2 years and 14% 3 years after TLE. Unemployed were 10% (t4), 5% (t5), and 7% (t6) of the patients. For 59% of all respondents it was very important to have a job. Predictors of successful vocational rehabilitation were employment prior to TLE, age <50 years, being self-employed or clerical employee, good physical functioning, good speech intelligibility, high motivation to go back to work, and support from colleagues. CONCLUSION: Only few laryngectomees return to work. However, even before TLE only a third of the patients was employed, another third was unemployed. Most of the patients receive pension retirement after TLE. As return to work is important for many patients, patient consultations should consider possibilities to support vocational rehabilitation before offering to apply for retirement.


Subject(s)
Laryngectomy/rehabilitation , Rehabilitation, Vocational , Adult , Cohort Studies , Disability Evaluation , Female , Follow-Up Studies , Germany , Humans , Interview, Psychological , Laryngectomy/psychology , Larynx, Artificial/psychology , Male , Middle Aged , Patient Satisfaction , Prospective Studies , Quality of Life/psychology , Rehabilitation, Vocational/psychology , Retirement/psychology , Social Participation/psychology , Speech Intelligibility , Surveys and Questionnaires
11.
Tissue Antigens ; 80(1): 66-7, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22469255

ABSTRACT

The newly detected HLA-B*15:238 is distinguished from HLA-B*15:52 by a single-nucleotide exchange at position 527 where T is replaced by A.


Subject(s)
Alleles , Exons/genetics , HLA-B15 Antigen/genetics , Mutation/genetics , Amino Acid Sequence , Germany , Humans , Molecular Sequence Data , Polymorphism, Single Nucleotide , Sequence Analysis, DNA , Stem Cell Transplantation , Tissue Donors
12.
J Viral Hepat ; 19(2): 77-87, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22239497

ABSTRACT

Combined pegylated interferon (PegIFN) and ribavirin represents the standard therapy for patients with chronic hepatitis C (CHC), which allows for sustained viral response (SVR) in up to 90% of patients depending on certain viral and host factors. Clinical studies have demonstrated the importance of adherence to therapy, that is, the ability of patients to tolerate and sustain a fully dosed therapy regimen. Adherence is markedly impaired by treatment-related adverse effects. In particular, haemolytic anaemia often requires dose reduction or termination of ribavirin treatment, which compromises treatment efficacy. Recent evidence points to a beneficial role of recombinant erythropoietin (EPO) in alleviating ribavirin-induced anaemia thereby improving quality of life, enabling higher ribavirin dosage and consequently improving SVR. However, no general consensus exists regarding the use of EPO for specific indications: its optimal dosing, treatment benefits and potential risks or cost efficiency. The Swiss Association for the Study of the Liver (SASL) has therefore organized an expert meeting to critically review and discuss the current evidence and to phrase recommendations for clinical practice. A consensus was reached recommending the use of EPO for patients infected with viral genotype 1 developing significant anaemia below 100 g/L haemoglobin and a haematocrit of <30% during standard therapy to improve quality of life and sustain optimal ribavirin dose. However, the evidence supporting its use in patients with pre-existing anaemia, non-1 viral genotypes, a former relapse or nonresponse, liver transplant recipients and cardiovascular or pulmonary disease is considered insufficient.


Subject(s)
Anemia/chemically induced , Anemia/drug therapy , Antiviral Agents/administration & dosage , Antiviral Agents/adverse effects , Erythropoietin/administration & dosage , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/drug therapy , Humans , Interferons/administration & dosage , Ribavirin/administration & dosage , Ribavirin/adverse effects , Treatment Outcome
13.
Haemophilia ; 18 Suppl 4: 101-4, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22726091

ABSTRACT

The elbow is a complex joint that is prone to bleeding episodes. These features as well as the close proximity of the ulnar nerve and the need to use the elbow in many activities of daily living can lead to a range of symptoms including recurrent bleeds, pain, instability or loss of range of movement and nerve compression. Conservative management includes splinting and proprioceptive retraining monitored by a physiotherapist who is a musculoskeletal expert in hemophilia care. In the event that conservative measures are not successful a range of surgical options may be indicated including elbow replacement. These approaches continue to be evaluated in both the short and long term in order to determine the most effective treatment for the symptomatic elbow.


Subject(s)
Elbow Joint , Hemarthrosis/therapy , Hemophilia A/complications , Hemophilia B/complications , Arthroplasty, Replacement, Elbow , Disease Management , Elbow Joint/anatomy & histology , Elbow Joint/physiopathology , Hemarthrosis/etiology , Hemarthrosis/physiopathology , Humans , Immobilization , Physical Therapy Modalities , Splints
14.
Acta Neurol Scand ; 126(4): 219-28, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22632110

ABSTRACT

Vigabatrin (VGB), an irreversible inhibitor of gamma-aminobutyric acid (GABA) transaminase, is approved as adjunct treatment of refractory partial seizures as well as infantile spasms. Although VGB has been proven to be effective, its use is limited by the risk of retinopathy and associated peripheral visual field defects. This review describes and analyzes current literature related to potential pathophysiologic mechanisms underlying VGB-mediated cellular toxicity. Animal data suggest that GABA mediates neural excitotoxicity. The amino acid taurine is concentrated in retinal cells, and deficiency of this amino acid may be involved in VGB-mediated retinal degeneration and possible phototoxicity.


Subject(s)
Anticonvulsants/adverse effects , Retinal Diseases/chemically induced , Retinal Diseases/metabolism , Taurine/metabolism , Vigabatrin/adverse effects , Animals , Epilepsy/drug therapy , Humans
15.
Nat Commun ; 13(1): 7844, 2022 12 21.
Article in English | MEDLINE | ID: mdl-36543773

ABSTRACT

Channelrhodopsins are light-gated ion channels used to control excitability of designated cells in large networks with high spatiotemporal resolution. While ChRs selective for H+, Na+, K+ and anions have been discovered or engineered, Ca2+-selective ChRs have not been reported to date. Here, we analyse ChRs and mutant derivatives with regard to their Ca2+ permeability and improve their Ca2+ affinity by targeted mutagenesis at the central selectivity filter. The engineered channels, termed CapChR1 and CapChR2 for calcium-permeable channelrhodopsins, exhibit reduced sodium and proton conductance in connection with strongly improved Ca2+ permeation at negative voltage and low extracellular Ca2+ concentrations. In cultured cells and neurons, CapChR2 reliably increases intracellular Ca2+ concentrations. Moreover, CapChR2 can robustly trigger Ca2+ signalling in hippocampal neurons. When expressed together with genetically encoded Ca2+ indicators in Drosophila melanogaster mushroom body output neurons, CapChRs mediate light-evoked Ca2+ entry in brain explants.


Subject(s)
Calcium , Drosophila melanogaster , Animals , Calcium/metabolism , Channelrhodopsins/genetics , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Ion Channels/physiology , Neurons/metabolism
16.
Elife ; 112022 10 17.
Article in English | MEDLINE | ID: mdl-36250621

ABSTRACT

In vertebrates, several forms of memory-relevant synaptic plasticity involve postsynaptic rearrangements of glutamate receptors. In contrast, previous work indicates that Drosophila and other invertebrates store memories using presynaptic plasticity of cholinergic synapses. Here, we provide evidence for postsynaptic plasticity at cholinergic output synapses from the Drosophila mushroom bodies (MBs). We find that the nicotinic acetylcholine receptor (nAChR) subunit α5 is required within specific MB output neurons for appetitive memory induction but is dispensable for aversive memories. In addition, nAChR α2 subunits mediate memory expression and likely function downstream of α5 and the postsynaptic scaffold protein discs large (Dlg). We show that postsynaptic plasticity traces can be induced independently of the presynapse, and that in vivo dynamics of α2 nAChR subunits are changed both in the context of associative and non-associative (familiarity) memory formation, underlying different plasticity rules. Therefore, regardless of neurotransmitter identity, key principles of postsynaptic plasticity support memory storage across phyla.


Subject(s)
Cholinergic Agents , Drosophila , Animals
17.
Hamostaseologie ; 31(2): 118-22, 2011 May 02.
Article in German | MEDLINE | ID: mdl-21152674

ABSTRACT

Acquired von Willebrand's disease (aVWD) is considered to be an underestimated cause of unexplained bleeding. Adsorption of von Willebrand factor (VWF) to tumour cells or hydroxyethyl starch and elimination of VWF by autoantibodies as well as shear stress-induced mechanical alteration of VWF with concomitant cleavage by enzymes may lead to an acquired deficiency of VWF and a bleeding disorder. We report a 39-year-old woman who developed spontaneous bleeding five years after surgical creation of an arteriovenous fistula (AVF) for haemodialysis treatment. AVWD type 2A was diagnosed after successful renal transplantation. One year after surgical closure of the AVF, the aVWD could not be verified again. Thus, the aVWD may have developed because of altered blood flow and shear stress inside the arteriovenous fistula.


Subject(s)
Arteriovenous Shunt, Surgical/adverse effects , Hemorrhage/etiology , Postoperative Complications/etiology , Renal Dialysis/adverse effects , von Willebrand Disease, Type 2/etiology , Adult , Blood Coagulation Tests , Female , Follow-Up Studies , Hemorrhage/blood , Humans , Kidney Transplantation , Postoperative Complications/blood , Risk Factors , von Willebrand Disease, Type 2/blood , von Willebrand Disease, Type 2/diagnosis
18.
Tissue Antigens ; 75(1): 88-9, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19895571

ABSTRACT

The new human leukocyte antigen (HLA)-DRB1 nucleotide sequence differs from HLA-DRB1*150101 in position 130 with an A instead of a T resulting in an amino acid change from Cysteine to Serine.


Subject(s)
Alleles , HLA-DR Antigens/genetics , Amino Acid Substitution , Base Sequence , Germany , HLA-DRB1 Chains , Humans , Molecular Sequence Data
19.
J Viral Hepat ; 17(12): 845-50, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20070503

ABSTRACT

Hepatocellular apoptosis plays a major role in the pathogenesis of chronic hepatitis C. It can be measured noninvasively by determining the circulating levels of cytokeratin-18 fragments. We hypothesized that the effect of antiviral therapy on this parameter will be different in patients with a sustained virological response, relapse (REL) and nonresponse (NR). We quantified cytokeratin-18 fragments in plasma of patients participating in the Swiss Hepatitis C cohort, who received antiviral therapy without stopping because of sides effects. A total of 315 patients were included, 183 with a sustained response, 64 with NR and 68 who relapsed. Mean levels ±SD of circulating cytokeratin-18 fragments before therapy were 174 ± 172 U/L for responsders, 188 ± 145 for nonresponders and 269 ± 158 U/L for patients who relapsed. The values were significantly higher in the REL group (ANOVA P < 0.006). A sustained response was associated with a significant improvement of the plasma levels (94 ± 92 U/L, paired test P < 0.000001), whereas there was no improvement in the nonresponder group (183 ± 158 U/L) and in the relapser group (158 ± 148 U/L). There was a weak correlation between alanine aminotransferase (ALT) and cytokeratin-18 fragment levels (r² = 0.35, P < 0.000001) before therapy but not after therapy and none with hepatitis C virus (HCV) viremia. Successful antiviral therapy results in a significant decrease in circulating levels of cytokeratin-18 fragments arguing for a reduction in hepatocellular apoptosis after clearance of the HCV. Baseline cytokeratin-18 fragment levels are higher in relapsers. Correlations with ALT are weak, suggesting that these two tests measure different but related processes.


Subject(s)
Antiviral Agents/therapeutic use , Hepacivirus/drug effects , Hepatitis C, Chronic/drug therapy , Keratin-18/blood , Viral Load/drug effects , Alanine Transaminase/blood , Apoptosis , Cohort Studies , Hepacivirus/genetics , Hepacivirus/physiology , Hepatitis C, Chronic/virology , Hepatocytes/physiology , Humans , RNA, Viral/blood , Recurrence , Switzerland , Treatment Outcome , Viremia/drug therapy , Viremia/virology
20.
Anaesthesist ; 59(1): 80-5, 2010 Jan.
Article in German | MEDLINE | ID: mdl-20084352

ABSTRACT

Some new blood products and plasma derivatives have extended the possibilities in hemotherapy to such an extent that the therapeutic and evidence-based therapy options can only really be managed with the aid of guidelines. Four approved plasma preparations are available in Germany: fresh frozen plasma, lyophilized plasma, solvent-detergent (SD) pool plasma and methylene blue-light-treated plasma. Evidence of the clinical efficacy of plasma is mainly based on uncontrolled observational studies, case reports or expert opinion. Plasma is indicated for complex coagulopathy associated with manifest or imminent bleeding, particularly with massive transfusion, disseminated intravascular coagulation and liver disease. With the exception of emergency situations when clotting assay results are not available in time, a clinically relevant coagulopathy must be verified before plasma is administered. The rapid infusion of at least 10 ml of plasma per kg body weight is required to significantly increase the respective clotting factor or inhibitor levels. Prothrombin complex concentrates (PPSB) should be preferred to plasma for the rapid reversal of oral anticoagulation. Side effects of plasma are rare but have to be considered.


Subject(s)
Blood Coagulation Disorders/therapy , Plasma , Disseminated Intravascular Coagulation/therapy , Evidence-Based Medicine , Germany , Guidelines as Topic , Hemorrhage/therapy , Humans , Prothrombin/therapeutic use , Risk Assessment , Transfusion Reaction
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