Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 185
Filter
Add more filters

Publication year range
1.
Ann Oncol ; 31(9): 1240-1250, 2020 09.
Article in English | MEDLINE | ID: mdl-32473302

ABSTRACT

BACKGROUND: Median overall survival (OS) for women with high-grade serous ovarian cancer (HGSOC) is ∼4 years, yet survival varies widely between patients. There are no well-established, gene expression signatures associated with prognosis. The aim of this study was to develop a robust prognostic signature for OS in patients with HGSOC. PATIENTS AND METHODS: Expression of 513 genes, selected from a meta-analysis of 1455 tumours and other candidates, was measured using NanoString technology from formalin-fixed paraffin-embedded tumour tissue collected from 3769 women with HGSOC from multiple studies. Elastic net regularization for survival analysis was applied to develop a prognostic model for 5-year OS, trained on 2702 tumours from 15 studies and evaluated on an independent set of 1067 tumours from six studies. RESULTS: Expression levels of 276 genes were associated with OS (false discovery rate < 0.05) in covariate-adjusted single-gene analyses. The top five genes were TAP1, ZFHX4, CXCL9, FBN1 and PTGER3 (P < 0.001). The best performing prognostic signature included 101 genes enriched in pathways with treatment implications. Each gain of one standard deviation in the gene expression score conferred a greater than twofold increase in risk of death [hazard ratio (HR) 2.35, 95% confidence interval (CI) 2.02-2.71; P < 0.001]. Median survival [HR (95% CI)] by gene expression score quintile was 9.5 (8.3 to -), 5.4 (4.6-7.0), 3.8 (3.3-4.6), 3.2 (2.9-3.7) and 2.3 (2.1-2.6) years. CONCLUSION: The OTTA-SPOT (Ovarian Tumor Tissue Analysis consortium - Stratified Prognosis of Ovarian Tumours) gene expression signature may improve risk stratification in clinical trials by identifying patients who are least likely to achieve 5-year survival. The identified novel genes associated with the outcome may also yield opportunities for the development of targeted therapeutic approaches.


Subject(s)
Cystadenocarcinoma, Serous , Ovarian Neoplasms , Cystadenocarcinoma, Serous/genetics , Female , Humans , Ovarian Neoplasms/genetics , Prognosis , Proportional Hazards Models , Survival Analysis , Transcriptome
2.
Brain Behav Immun ; 73: 252-260, 2018 10.
Article in English | MEDLINE | ID: mdl-29763737

ABSTRACT

BACKGROUND: Studies to date have reported several associations between single nucleotide polymorphisms (SNPs) and cancer related fatigue (CRF), but have been limited by small sample sizes, missing adjustment for relevant covariates or multiple testing, as well as varying CRF definitions, i.e. time and method of assessment. This study aimed to validate previously reported associations using the largest independent breast cancer sample to date and to evaluate further functional cytokine variants in relation to total CRF and all relevant CRF subdomains (physical, cognitive, and affective CRF). METHOD: 45 candidate SNPs in inflammatory pathway genes were selected based on previous reports (16 SNPs) or regulatory function (29 SNPs). Breast cancer patients recruited between 2002 and 2005 provided information on CRF at first follow-up (FU1) (N = 1389) and second follow-up (FU2) (N = 950), a median of 6.2 years and 11.7 years respectively after diagnosis. SNP associations were assessed using linear regression models on CRF scores separately for FU1 and FU2. Additionally, patients with persistent fatigue (fatigued at both time-points) were compared to those never fatigued using logistic regression models (N = 684). All analyses were adjusted for relevant covariates. Secondary analyses were conducted for CRF subdomains. RESULTS: For total CRF none of the previously reported associations were confirmed after correction for multiple testing. The p-value distribution of all SNPs was not different than the one expected by chance. Analyses of CRF subdomains yielded a significant association between TNF-α rs3093662 and persistent physical CRF (Odds Ratio (OR) = 3.23, 95% Confidence Interval (CI) = 1.71-6.10, p = 0.0003). CONCLUSION: We were unable to confirm previously reported findings, suggesting that individual SNPs are unlikely to be of clinical utility. Further investigations in well powered studies are warranted, which consider genetic heterogeneity according to subdomains of CRF.


Subject(s)
Breast Neoplasms/genetics , Fatigue/genetics , Adult , Aged , Breast Neoplasms/complications , Breast Neoplasms/immunology , Cohort Studies , Female , Genetic Predisposition to Disease , Genetic Variation/genetics , Genotype , Humans , Inflammation/genetics , Linear Models , Logistic Models , Longitudinal Studies , Middle Aged , Odds Ratio , Polymorphism, Single Nucleotide/genetics , Risk Factors , Surveys and Questionnaires , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism
3.
Appl Environ Microbiol ; 83(13)2017 07 01.
Article in English | MEDLINE | ID: mdl-28455336

ABSTRACT

Most described nitrate-reducing Fe(II)-oxidizing bacteria (NRFeOB) are mixotrophic and depend on organic cosubstrates for growth. Encrustation of cells in Fe(III) minerals has been observed for mixotrophic NRFeOB but not for autotrophic phototrophic and microaerophilic Fe(II) oxidizers. So far, little is known about cell-mineral associations in the few existing autotrophic NRFeOB. Here, we investigate whether the designated autotrophic Fe(II)-oxidizing strain (closely related to Gallionella and Sideroxydans) or the heterotrophic nitrate reducers that are present in the autotrophic nitrate-reducing Fe(II)-oxidizing enrichment culture KS form mineral crusts during Fe(II) oxidation under autotrophic and mixotrophic conditions. In the mixed culture, we found no significant encrustation of any of the cells both during autotrophic oxidation of 8 to 10 mM Fe(II) coupled to nitrate reduction and during cultivation under mixotrophic conditions with 8 to 10 mM Fe(II), 5 mM acetate, and 4 mM nitrate, where higher numbers of heterotrophic nitrate reducers were present. Two pure cultures of heterotrophic nitrate reducers (Nocardioides and Rhodanobacter) isolated from culture KS were analyzed under mixotrophic growth conditions. We found green rust formation, no cell encrustation, and only a few mineral particles on some cell surfaces with 5 mM Fe(II) and some encrustation with 10 mM Fe(II). Our findings suggest that enzymatic, autotrophic Fe(II) oxidation coupled to nitrate reduction forms poorly crystalline Fe(III) oxyhydroxides and proceeds without cellular encrustation while indirect Fe(II) oxidation via heterotrophic nitrate-reduction-derived nitrite can lead to green rust as an intermediate mineral and significant cell encrustation. The extent of encrustation caused by indirect Fe(II) oxidation by reactive nitrogen species depends on Fe(II) concentrations and is probably negligible under environmental conditions in most habitats.IMPORTANCE Most described nitrate-reducing Fe(II)-oxidizing bacteria (NRFeOB) are mixotrophic (their growth depends on organic cosubstrates) and can become encrusted in Fe(III) minerals. Encrustation is expected to be harmful and poses a threat to cells if it also occurs under environmentally relevant conditions. Nitrite produced during heterotrophic denitrification reacts with Fe(II) abiotically and is probably the reason for encrustation in mixotrophic NRFeOB. Little is known about cell-mineral associations in autotrophic NRFeOB such as the enrichment culture KS. Here, we show that no encrustation occurs in culture KS under autotrophic and mixotrophic conditions while heterotrophic nitrate-reducing isolates from culture KS become encrusted. These findings support the hypothesis that encrustation in mixotrophic cultures is caused by the abiotic reaction of Fe(II) with nitrite and provide evidence that Fe(II) oxidation in culture KS is enzymatic. Furthermore, we show that the extent of encrustation caused by indirect Fe(II) oxidation by reactive nitrogen species depends on Fe(II) concentrations and is probably negligible in most environmental habitats.


Subject(s)
Bacteria/metabolism , Ferrous Compounds/metabolism , Minerals/metabolism , Nitrates/metabolism , Acetates/metabolism , Bacteria/genetics , Bacteria/growth & development , Chemoautotrophic Growth , Ferric Compounds/metabolism , Nitrites/metabolism , Oxidation-Reduction
4.
Lett Appl Microbiol ; 61(4): 346-53, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26119060

ABSTRACT

UNLABELLED: The mechanisms and organisms involved in the natural formation of volatile organohalogen compounds (VOX) are largely unknown. We provide evidence that the common and widespread soil bacterium Sinorhizobium meliloti strain 1021 is capable of producing up to 3338·6 ± 327·8 ng l(-1) headspace volume of chloroform (CHCl3 ) and 807·8 ± 13·5 ng l(-1)  headspace volume of tetrachloroethene (C2 Cl4 ) within 1 h when grown in soil extract medium. Biotic VOX formation has been suggested to be linked to the activity of halogenating enzymes such as haloperoxidases. We tested if the observed VOX formation by S. meliloti can be attributed to one of its chloroperoxidases (Smc01944) that is highly expressed in the presence of H2 O2. However, addition of 10 mmol l(-1) H2 O2 to the S. meliloti cultures decreased VOX formation by 52% for chloroform and 25% for tetrachloroethene, while viable cell numbers decreased by 23%. Interestingly, smc01944 gene expression increased 450-fold. The quantification of extracellular chlorination activity in cell suspension experiments did not provide evidence for a role of S. meliloti chloroperoxidases in the observed VOX formation. This suggests that a momentarily unknown mechanism which requires no H2 O2 might be responsible for the VOX formation by S. meliloti. Regardless of the underlying mechanism our results suggest that the soil bacterium S. meliloti might be an important source of VOX in soils. SIGNIFICANCE AND IMPACT OF THE STUDY: Volatile organohalogen compounds (VOX) strongly influence atmospheric chemistry and Earth's climate. Besides anthropogenic emissions they are naturally produced by either abiotic or biotic pathways in various environments. Particularly in soils, microbial processes drive the natural halogen cycle but the direct link to microbial VOX formation has not been studied in detail yet. In this study we provide evidence that the common and widespread soil bacterium Sinorhizobium meliloti strain 1021 forms chloroform and tetrachloroethene. The potential contribution of S. meliloti to soil VOX release could significantly influence soil and atmospheric chemistry.


Subject(s)
Chloride Peroxidase/metabolism , Chloroform/metabolism , Hydrogen Peroxide/metabolism , Sinorhizobium meliloti/metabolism , Soil Microbiology , Tetrachloroethylene/metabolism , Volatile Organic Compounds/metabolism , Sinorhizobium meliloti/genetics , Soil
5.
Gesundheitswesen ; 77(2): e15-9, 2015 Feb.
Article in German | MEDLINE | ID: mdl-25714193

ABSTRACT

AIM OF THE STUDY: How can 2 pseudonymised data sets be linked? Using the example of data from the Berlin Myocardial Infarction Registry and from a German sickness fund (AOK Nordost) we will demonstrate how record linkage can be achieved without personal identifiers. METHODS: In different steps the method of deterministic record linkage with indirect identifiers: age, sex, hospital admission date and time, will be explained. RESULTS: We were able to show that 80.6% of the expected maximum number of patients were matched with our approach. As a result we had no duplicate matches in the linkage process, where one AOK patient was linked to 2 or more BMIR patients or vice versa. The matching variables produced enough uniqueness to be used as indirect patient identifiers. CONCLUSION: Deterministic record linkage with the following indirect indicators: age, sex, hospital admission date and time was possible in our study of patients with myocardial infarction in a circumscribed geographical region, which limited the number of cases and avoided mismatches.


Subject(s)
Data Anonymization , Hospital Information Systems/statistics & numerical data , Medical Record Linkage/methods , Myocardial Infarction/epidemiology , National Health Programs/statistics & numerical data , Registries/statistics & numerical data , Adult , Data Accuracy , Female , Germany/epidemiology , Hospitalization/statistics & numerical data , Humans , Information Storage and Retrieval/methods , Information Storage and Retrieval/statistics & numerical data , Male , Meaningful Use/statistics & numerical data , Middle Aged , Myocardial Infarction/diagnosis , Myocardial Infarction/therapy
6.
Environ Sci Technol ; 48(16): 9170-8, 2014 Aug 19.
Article in English | MEDLINE | ID: mdl-25073729

ABSTRACT

Volatile halogenated organic compounds (VOX) contribute to ozone depletion and global warming. There is evidence of natural VOX formation in many environments ranging from forest soils to salt lakes. Laboratory studies have suggested that VOX formation can be chemically stimulated by reactive Fe species while field studies have provided evidence for direct biological (enzymatic) VOX formation. However, the relative contribution of abiotic and biotic processes to global VOX budgets is still unclear. The goals of this study were to quantify VOX release from sediments from a hypersaline lake in Western Australia (Lake Strawbridge) and to distinguish between the relative contributions of biotic and abiotic VOX formation in microbially active and sterilized microcosms. Our experiments demonstrated that the release of organochlorines from Lake Strawbridge sediments was mainly biotic. Among the organochlorines detected were monochlorinated, e.g., chloromethane (CH3Cl), and higher chlorinated VOX compounds such as trichloromethane (CHCl3). Amendment of sediments with either Fe(III) oxyhydroxide (ferrihydrite) or a mixture of lactate/acetate or both ferrihydrite and lactate/acetate did not stimulate VOX formation. This suggests that although microbial Fe(III) reduction took place, there was no stimulation of VOX formation via Fe redox transformations or the formation of reactive Fe species under our experimental conditions.


Subject(s)
Air Pollutants , Hydrocarbons, Chlorinated , Acetates/pharmacology , Air Pollutants/chemistry , Air Pollutants/metabolism , Ferric Compounds/pharmacology , Geologic Sediments/chemistry , Geologic Sediments/microbiology , Hydrocarbons, Chlorinated/chemistry , Hydrocarbons, Chlorinated/metabolism , Lactic Acid/pharmacology , Lakes , Oxidation-Reduction , Salinity , Western Australia
7.
Herz ; 39(2): 212-8, 2014 Mar.
Article in English | MEDLINE | ID: mdl-23712825

ABSTRACT

BACKGROUND: The number of elderly and very elderly patients undergoing percutaneous coronary interventions (PCI) is increasing. We therefore analyzed data from the German ALKK registry (Arbeitsgemeinschaft Leitende Krankenhausärzte; Working Group of Hospital Cardiologists) to determine differences in procedural features, antithrombotic treatment, and in-hospital outcome in patients with coronary artery disease (CAD) according to age in a large series of patients. METHODS AND RESULTS: The present analysis was based on the data of 35,534 consecutive patients undergoing elective PCI who were enrolled in the ALKK registry. Of these 27,145 (76.4 %) were younger than 75 years, 7,645 (21.5 %) were aged between 75 and 84 years, and 744 (2.1 %) patients were older than 85 years. Mean age was 68.5 years (60.9-74.5 years), and 25,784 patients (72.6 %) were male. Overall intraprocedural events were very low (1.1 %) and there was no significant difference between the three age groups [< 75 years (1.1 %); 75-< 85 years (1.2 %); ≥ 85 years (0.5 %) (p = not significant)]. Rates of in-hospital death, stroke and transient ischemic attack (TIA), as well as the combined endpoint in-hospital major adverse cardiac and cerebrovascular events (MACCE) were also very low (0.6 % vs. 0.9 % vs. 0.9 %; p < 0.001) but significantly higher in elderly patients with no further increase in the very elderly patient group. CONCLUSION: We found no differences in this registry in intraprocedural complications during elective PCI between younger and elderly patients. Although in-hospital MACCE were somewhat higher in the elderly, the overall event rate was low and thus elderly patients should not be deprived from this therapy because of age alone.


Subject(s)
Coronary Artery Disease/surgery , Percutaneous Coronary Intervention/mortality , Postoperative Complications/mortality , Registries , Thrombosis/mortality , Adult , Age Distribution , Aged , Aged, 80 and over , Female , Germany/epidemiology , Hospital Mortality , Humans , Male , Middle Aged , Postoperative Complications/prevention & control , Prevalence , Risk Factors , Sex Distribution , Survival Rate , Thrombosis/prevention & control , Treatment Outcome
8.
ACS Energy Lett ; 9(4): 1331-1338, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38633991

ABSTRACT

Hydrogen peroxide (H2O2) is a widely used green oxidant. Until now, research has focused on the development of efficient catalysts for the two-electron oxygen reduction reaction (2e- ORR). However, electrolyte effects on the 2e- ORR have remained little understood. We report a significant effect of alkali metal cations (AMCs) on carbons in acidic environments. The presence of AMCs at a glassy carbon electrode shifts the half wave potential from -0.48 to -0.22 VRHE. This cation-induced enhancement effect exhibits a uniquely sensitive on/off switching behavior depending on the voltammetric protocol. Voltammetric and in situ X-ray photoemission spectroscopic evidence is presented, supporting a controlling role of the potential of zero charge of the catalytic enhancement. Density functional theory calculations associate the enhancement with stabilization of the *OOH key intermediate as a result of locally induced field effects from the AMCs. Finally, we developed a refined reaction mechanism for the H2O2 production in the presence of AMCs.

9.
Clin Hemorheol Microcirc ; 79(1): 167-178, 2021.
Article in English | MEDLINE | ID: mdl-34487029

ABSTRACT

BACKGROUND/AIM: Tissue pathogenesis of aortic valve (AV) stenosis is research focus in cardiac surgery. Model limitations of conventional 2D culture of human or porcine valvular interstitial/endothelial cells (VIC/VECs) isolated from aortic valve tissues but also limited ability of (small) animal models to reflect human (patho)physiological situation in AV position raise the need to establish an in vitro setup using AV tissues. Resulting aim is to approximate (patho)physiological conditions in a dynamic pulsatile Microphysiological System (MPS) to culture human and porcine AV tissue with preservation of tissue viability but also defined ECM composition. MATERIALS/METHODS: A tissue incubation chamber (TIC) was designed to implement human or porcine tissues (3×5 mm2) in a dynamic pulsatile culture in conventional cell culture ambience in a MPS. Cell viability assays based on lactate dehydrogenase (LDH)-release or resazurin-conversion were tested for applicability in the system and applied for a culture period of 14 days with interval evaluation of tissue viability on every other day. Resazurin-assay setup was compared in static vs. dynamic culture using varying substance saturation settings (50-300µM), incubation times and tissue masses and was consequently adapted. RESULTS: Sterile dynamic culture of human and porcine AV tissue segments was established at a pulsatile flow rate range of 0.9-13.4µl/s. Implementation of tissues was realized by stitching the material in a thermoplastic polyurethane (TPU)-ring and insertion in the TIC-MPS-system. Culture volume of 2 ml caused LDH dilution not detectable in standard membrane integrity assay setup. Therefore, detection of resazurin-conversion of viable tissue was investigated. Optimal incubation time for viability conversion was determined at two hours at a saturated concentration of 300µM resazurin. Measurement in static conditions was shown to offer comparable results as dynamic condition but allowing optimal handling and TIC sterilization protocols for long term culture. Preliminary results revealed favourable porcine AV tissue viability over a 14 day period confirmed via resazurin-assay comparing statically cultured tissue counterparts. CONCLUSIONS: Human and porcine AV tissue can be dynamically cultured in a TIC-MPS with monitoring of tissue viability using an adapted resazurin-assay setup. Preliminary results reveal advantageous viability of porcine AV tissues after dynamic TIC-MPS culture compared to static control.


Subject(s)
Aortic Valve Stenosis , Aortic Valve , Animals , Endothelial Cells , Humans , Oxazines , Swine , Tissue Survival , Xanthenes
10.
Breast ; 56: 103-109, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33668004

ABSTRACT

BACKGROUND: Low-grade inflammation has been associated with cancer related fatigue (CRF). However, most studies focused on CRF during or shortly after treatment. Longitudinal studies are rare with inconsistent results. We assessed the association of inflammatory biomarkers with total CRF and all subdomains (physical, cognitive, affective) in long-term breast cancer survivors. METHOD: Patients recruited between 2002 and 2005 provided information on CRF at first follow-up (FU1) (N = 1292) and second follow-up (FU2) (N = 1205), after a median of 6.2 years and 11.7 years, respectively. Associations of 11 inflammatory biomarkers with CRF at FU1 and at FU2 were assessed using linear regression models. Logistic regression models were used to compare patients fatigued at both time-points and those never fatigued (N = 932). RESULTS: C-reactive protein (CRP) was significantly associated with total CRF at FU1 (ß = 1.47, 95%CI = 0.62-2.31, p = 0.0007), at FU2 (ß = 1.98, 95 %CI = 0.96-2.99, p = 0.0001) and with persistent CRF (OR = 1.29, 95%CI = 1.13-1.47, p < 0.0001). IL-6 levels were associated with total CRF at FU1 (ß = 1.01, 95%CI = 0.43-1.59, p = 0.0006), but not with CRF at FU2 or persistent CRF. No association remained significant after adjustment for relevant covariates. DISCUSSION: CRP and Il-6 were associated with risk of CRF in long-term breast cancer survivors, but were not independent of other known risk factors, suggesting that currently studied inflammatory markers are not suitable to identify patients at risk of long-term CRF.


Subject(s)
Breast Neoplasms/psychology , Cancer Survivors/psychology , Fatigue/etiology , Quality of Life , Aged , Biomarkers, Tumor , Breast Neoplasms/complications , C-Reactive Protein/analysis , Cytokines/blood , Fatigue/blood , Fatigue/psychology , Female , Humans , Inflammation , Interleukin-6/blood , Middle Aged
11.
Anal Biochem ; 393(1): 141-4, 2009 Oct 01.
Article in English | MEDLINE | ID: mdl-19539596

ABSTRACT

The sandwich culture is the most widely used long-term culture system for functional primary hepatocytes. Despite its advantages, the currently available protocols for protein and RNA extraction are either time-consuming or contain steps that may skewer the results. This paper describes improved protocols for RNA and protein extraction from sandwich cultures that are easy to perform, require short working time, and use no additional enzymatic reactions that could change the expression profile of the cells. The quality of the RNA is excellent, allowing also applications requiring high purity such as microarrays. In general, the protocols are suited for any cells in 3D collagen culture.


Subject(s)
Cell Culture Techniques/methods , Hepatocytes/chemistry , Proteins/isolation & purification , RNA/isolation & purification , Cells, Cultured , Collagen
12.
Science ; 262(5130): 102-5, 1993 Oct 01.
Article in English | MEDLINE | ID: mdl-8211112

ABSTRACT

In the assembly of a prespliceosome, U2 small nuclear ribonucleoprotein (snRNP) functions in pre-messenger RNA (mRNA) splicing together with splicing factors (SFs) 3a, SF3b, and several other proteins. The 17S but not the 12S form of U2 snRNP is active in splicing-complex formation. Here it is shown that the SF3a subunits correspond to three of the 17S U2 snRNP-specific polypeptides. SF3a interacts with U2 snRNP in the presence of SF3b to generate a structure similar to 17S U2 snRNP, which suggests a function for SF3a and SF3b in the incorporation of U2 snRNP into the spliceosome. Furthermore, the 60-kilodalton subunit of SF3a is related to the yeast splicing protein PRP9.


Subject(s)
Fungal Proteins/metabolism , Nuclear Proteins/metabolism , RNA Splicing , Ribonucleoprotein, U2 Small Nuclear/metabolism , Saccharomyces cerevisiae Proteins , Spliceosomes/metabolism , Adenosine Triphosphate/metabolism , Cross Reactions , Electrophoresis, Polyacrylamide Gel , Fungal Proteins/chemistry , Fungal Proteins/immunology , Humans , Nuclear Proteins/chemistry , Nuclear Proteins/immunology , RNA Splicing Factors , RNA-Binding Proteins , Ribonucleoprotein, U2 Small Nuclear/chemistry
13.
Europace ; 10(12): 1375-80, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18776196

ABSTRACT

AIMS: Cardiac resynchronization therapy (CRT) has become a standard therapy in cases of heart failure and asynchrony. Unfortunately, 20-30% of patients were non-responsive (NR) to CRT. In this report we used cardiac contractility modulation (CCM) as an adjunctive measure in NR patients. METHODS AND RESULTS: Sixteen NR patients, mean age 65 +/- 9 years, mean ejection fraction 27.3 +/- 7.4%, and New York Heart Association (NYHA) class III (n = 9) or IV (n = 7) despite CRT plus optimized medical therapy, received an additional CCM-implantation contra-lateral to the existing CRT system (OPTIMIZER III, Impulse Dynamics, Orangeburg, NY, USA). Cardiac contractility modulation delivers non-excitatory high-energy stimulatory impulses during the absolute refractory period, thus improving contractility [left ventricular (LV) dp/dt)] by stimulating the septum with two screw-in leads and one additional atrial lead for triggering the impulses. Acute LV dp/dt changes induced by CCM stimulation were measured by 5F Millar catheters placed in the LV during the implantation procedure in 14 of 16 cases. Patients were followed prospectively. Left ventricular dp/dt increased from a mean of 568 +/- 153 to 646 +/- 147 mmHg/s (+14%, P < 0.001) in the acute intraoperative testing. We noted the following complications and events during a follow-up of an average of 147 +/- 80 days (range 68-326) after CCM: intraoperative ventricular flutter needing cardioversion (n = 1), atrial lead dislocation (n = 1), coronary sinus (CS) lead dislocation (n = 1), painful stimulation requiring repositioning of septal leads (n = 1), true defibrillator shocks (n = 3), cardiac decompensations (n = 3), atrial fibrillation (n = 4), renal failure (n = 1), and pneumonia (n = 2). NYHA class improved from 3.4 to 2.8 (P < 0.01), and the ejection fraction increased from 27.3 +/- 5 to 31.1 +/- 6 (P < 0.01). Three patients (19%) died suddenly presumably due to electromechanical dissociation after 318, 104, and 81 days. No electrical interference was observed between the CCM and CRT systems, and in particular, at no time was the CRT-implantable cardioverter-defibrillator found to be delivering inadequate shocks. CONCLUSION: The CCM method is feasible and could be applied with calculated risks as a possible useful adjunct in CRT-NR when no other options are available; however, mortality and event rates are high in this very sick population.


Subject(s)
Cardiac Pacing, Artificial , Heart Failure/diagnosis , Heart Failure/prevention & control , Ventricular Dysfunction, Left/diagnosis , Ventricular Dysfunction, Left/prevention & control , Aged , Female , Humans , Male , Treatment Failure
14.
Mol Cell Biol ; 13(1): 307-19, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8380223

ABSTRACT

Small nuclear (sn) ribonucleoprotein (RNP) U2 functions in the splicing of mRNA by recognizing the branch site of the unspliced pre-mRNA. When HeLa nuclear splicing extracts are centrifuged on glycerol gradients, U2 snRNPs sediment at either 12S (under high salt concentration conditions) or 17S (under low salt concentration conditions). We isolated the 17S U2 snRNPs from splicing extracts under nondenaturing conditions by using centrifugation and immunoaffinity chromatography and examined their structure by electron microscope. In addition to common proteins B', B, D1, D2, D3, E, F, and G and U2-specific proteins A' and B", which are present in the 12S U2 snRNP, at least nine previously unidentified proteins with apparent molecular masses of 35, 53, 60, 66, 92, 110, 120, 150, and 160 kDa bound to the 17S U2 snRNP. The latter proteins dissociate from the U2 snRNP at salt concentrations above 200 mM, yielding the 12S U2 snRNP particle. Under the electron microscope, the 17S U2 snRNPs exhibited a bipartite appearance, with two main globular domains connected by a short filamentous structure that is sensitive to RNase. These findings suggest that the additional globular domain, which is absent from 12S U2 snRNPs, contains some of the 17S U2-specific proteins. The 5' end of the RNA in the U2 snRNP is more exposed for reaction with RNase H and with chemical probes when the U2 snRNP is in the 17S form than when it is in the 12S form. Removal of the 5' end of this RNA reduces the snRNP's Svedberg value from 17S to 12S. Along with the peculiar morphology of the 17S snRNP, these data indicate that most of the 17S U2-specific proteins are bound to the 5' half of the U2 snRNA.


Subject(s)
RNA Splicing , Ribonucleoprotein, U2 Small Nuclear/chemistry , Base Sequence , Cell Fractionation/methods , Cell Nucleus/chemistry , HeLa Cells , Humans , Hydrogen Bonding , In Vitro Techniques , Microscopy, Electron , Molecular Sequence Data , Molecular Weight , Nucleic Acid Conformation , RNA-Binding Proteins/chemistry , Ribonuclease H/pharmacology
15.
Drug Metabol Drug Interact ; 22(2-3): 195-200, 2007.
Article in English | MEDLINE | ID: mdl-17708069

ABSTRACT

Rhabdomyolysis is a well known side effect of statin therapy. Several drugs may increase its risk by drug-drug interactions. In particular, patients with heart disease receive more and more different compounds to cope with all the pathomechanisms involved and may therefore be of high risk for side effects. We report a case of rhabdomyolysis in a patient with heart failure on a multi-drug regimen caused by a drug interaction between chronic statin therapy (simvastatin), amiodarone and newly administrated digitoxin. The patient recovered fully after cessation of simvastatin therapy, the other drugs were given continuously. Potential mechanisms of this event are discussed. Most interesting in this case is that rhabdomyolysis occurred only after starting digitoxin after long-term therapy with the statin.


Subject(s)
Amiodarone/adverse effects , Anti-Arrhythmia Agents/adverse effects , Anticholesteremic Agents/adverse effects , Digitoxin/adverse effects , Rhabdomyolysis/chemically induced , Simvastatin/adverse effects , Drug Interactions , Heart Failure/drug therapy , Humans , Male , Middle Aged , Risk Factors
16.
Herzschrittmacherther Elektrophysiol ; 18(4): 243-9, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18084798

ABSTRACT

Cardiac resynchronization therapy (CRT) using coronary sinus (CS) leads is an established method for the therapy of congestive heart failure (CHF) in the case of asynchronous ventricular contractions. Successful therapy depends on the placement of left ventricular leads usually via the coronary sinus (CS), a technically more challenging procedure than regular pacemaker implantations. Without specific precautions CRT implantation can be the gateway to a time consuming nightmare. Therefore CS lead implantation methods, with a focus on complications, were reviewed according to the literature and own experience with approximately 500 procedures from 1999-2007.


Subject(s)
Coronary Sinus , Electrodes, Implanted/adverse effects , Foreign-Body Migration/etiology , Heart Failure/therapy , Pacemaker, Artificial/adverse effects , Postoperative Complications/etiology , Ventricular Dysfunction/therapy , Coronary Sinus/injuries , Electric Countershock , Foreign-Body Migration/therapy , Humans , Postoperative Complications/prevention & control , Postoperative Complications/therapy , Prosthesis Failure
17.
Chem Commun (Camb) ; 53(37): 5175-5178, 2017 May 04.
Article in English | MEDLINE | ID: mdl-28439582

ABSTRACT

Palladium nanoparticles stabilized by poly(vinylpyrrolidone) catalyze Tsuji-Trost allylations in water with very high turnover numbers. The di-allylation of methylene active compounds and the allylation of bio-based phenols was performed in high yield. The allylation of lignin showed a high selectivity towards the phenolic OH groups.

18.
Article in English | MEDLINE | ID: mdl-16547655

ABSTRACT

INTRODUCTION: Cardiac resynchronization therapy (CRT) using coronary sinus (CS) leads is a new method for the therapy of congestive heart failure (CHF). Because the intervention is more complex than regular pacemaker implantations, information on the feasibility and side effects of this method are of interest. METHODS: From 1999 to June 2005, CRT implantations were attempted in 244 patients (pts; mean age 64+/-12 years, range 14-90 years), 82% were male, 44% had coronary artery disease, 29% were in atrial fibrillation, 71 had preexisting pacemakers. RESULTS: In 97% of the pts the intervention was successful (27% of the systems with defibrillation capabilities). In 285 interventions, 255 CS leads were positioned according to CS vein anatomy in 130 posterolateral, 97 anterolateral and 28 anterior side branches (16 patients received 2 CS leads). Over-the-wire leads were used in 88%, 71% were additionally preshaped. We observed no mortality but 37 complications (12.5%): CS dissection in 9, CS perforation in 1, ventricular fibrillation in 4, asystole in 5, pulmonary edema in 1, pneumothorax in 2, need for early CS lead revision in 19 (dislodgement n=7, phrenic nerve stimulation n=12) and infection with explantation in 2 cases. An improvement in NYHA functional class was found in 88% of pts (only 55% if anterior lead position). CONCLUSION: Perioperative complications during CS lead implantation occur in 10-15% of cases. Most patients responded well to CRT. Patients should be informed about the possible need for a reoperation. During implantation, immediate defibrillation and stimulation capabilities must be available. Anterior lead positions should be avoided.


Subject(s)
Atrial Fibrillation/epidemiology , Atrial Fibrillation/prevention & control , Electrodes, Implanted , Pacemaker, Artificial/statistics & numerical data , Postoperative Complications/epidemiology , Prosthesis Implantation/statistics & numerical data , Risk Assessment/methods , Adolescent , Adult , Aged , Aged, 80 and over , Cardiac Pacing, Artificial/statistics & numerical data , Comorbidity , Coronary Vessels/surgery , Female , Humans , Incidence , Male , Middle Aged , Retrospective Studies , Risk Factors , Treatment Outcome , Veins/surgery
19.
Herzschrittmacherther Elektrophysiol ; 17(4): 185-90, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17211748

ABSTRACT

BACKGROUND: Acute studies in cardiac resynchronization therapy (CRT) showed that hemodynamic effects may depend on the coronary sinus (CS) lead position. However, there are no data on the longterm effect of CS lead position. METHODS: In 45 heart failure patients with left bundle branch block and QRS >150 ms (age 59+/-10 years, 17 dilative cardiomyopathy, 23 ischemic, 5 valvular), biventricular pacemakers were implanted. CS leads were positioned in posterior (P, n=15), lateral (L, n=19) or, if no other option available, anterior (A, n=11) side branches. Before and 6 months after implantation, clinical state, echocardiography, brain natriuretic peptide (BNP) and right heart catheterization were evaluated. RESULTS: Baseline parameters were similar between groups. After 6 months, there were 32/34 responders in groups P and L compared to 7/11 responders in group A (94 vs groups P and L: Arterial pressure +8 and +9% vs +2%; PCWP -23 and -15% vs -4%, pulmonary pressure -18 and -12% vs -3% (p<0.01 for A vs P+L); cardiac index +21 and +12% vs +11% (p=0.03 for A vs P). BNP was reduced by 55, 35, and 27% (p=0.05 for A vs P). Ejection fraction increased in P and L by 40 and 41%, respectively, but only by +19% in A (p<0.03 for A vs P+L). CONCLUSION: Chronic CRT improves ejection fraction, BNP and hemodynamic measurements predominantly in patients with lateral and posterior CS lead positions. Anterior lead positions should be avoided.


Subject(s)
Blood Pressure/physiology , Bundle-Branch Block/therapy , Cardiac Output/physiology , Electrocardiography , Heart Failure/therapy , Heart Rate/physiology , Myocardial Contraction/physiology , Pacemaker, Artificial , Pulmonary Wedge Pressure/physiology , Stroke Volume/physiology , Aged , Bundle-Branch Block/etiology , Bundle-Branch Block/physiopathology , Carbon Dioxide/blood , Cardiac Catheterization , Echocardiography , Female , Follow-Up Studies , Heart Failure/etiology , Heart Failure/physiopathology , Hemoglobinometry , Humans , Male , Middle Aged , Oxygen/blood , Ventricular Function, Left/physiology
20.
FEMS Microbiol Rev ; 17(3): 341-8, 1995 Oct.
Article in English | MEDLINE | ID: mdl-7576772

ABSTRACT

Characterization of the heat shock response in Clostridium acetobutylicum has indicated that at least 15 proteins are induced by a temperature upshift from 30 to 42 degrees C. These so-called heat shock proteins include DnaK and GroEL, two highly conserved molecular chaperones. Several genes encoding heat shock proteins of C. acetobutylicum have been cloned and analysed. The dnaK operon includes the genes orfA (a heat shock gene with an unknown function), grpE, dnaK, and dnaJ; and the groE operon the genes groES and groEL. The hsp18 gene coding for a member of the small heat shock protein family constitutes a monocistronic operon. Interestingly, the heat shock response in this bacterium is regulated by a mechanism, which is obviously different from that found in Escherichia coli. So far, no evidence for a heat shock-specific sigma factor of the RNA polymerase in C. acetobutylicum has been found. In this bacterium, like in many Gram-positive and several Gram-negative bacteria, a conserved inverted repeat is located upstream of chaperone/chaperonin-encoding stress genes such as dnaK and groEL and may be implicated as a cis-acting regulatory site. The inverted repeat is not present in the promoter region of hsp18. Therefore, in C. acetobutylicum there are at least two classes of heat shock genes with respect to the type of regulation. Evidence has been found that a repressor is involved in the regulation of the heat shock response in C. acetobutylicum. However, this regulation seems to be independent of the inverted repeat motif, and the mechanism by which the inverted repeat motif mediates regulation remains to be elucidated.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Clostridium/genetics , Gene Expression Regulation, Bacterial , Heat-Shock Response/genetics , Base Sequence , Molecular Sequence Data
SELECTION OF CITATIONS
SEARCH DETAIL