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1.
Pediatr Radiol ; 50(1): 28-37, 2020 01.
Article in English | MEDLINE | ID: mdl-31583441

ABSTRACT

BACKGROUND: The acquisition of chest radiographs in neonates is of critical importance in diagnostics because of the risk of respiratory distress syndrome and pneumothorax in preterm infants. OBJECTIVE: To achieve a dose reduction while preserving a diagnostic image quality for chest radiographs of neonates. MATERIALS AND METHODS: All radiographs, generated on a fully digital X-ray unit by using a neonatal chest phantom, were evaluated under variation of the tube voltage (40-70 kV) and mAs levels (1-10.2 mAs) with and without an additional 0.1-mm copper (Cu) filtration. Noise, contrast and contrast-to-noise ratio for bronchus, heart, lungs and vessels were determined. Visual assessment of the image quality was carried out by three radiologists using a Likert scale. To evaluate a maximally possible dose reduction, the dose of the radiographs with still acceptable image quality at a minimal dose was compared to the dose of the radiographs with the standard settings used in clinical routine. RESULTS: The noise showed decreasing values with increasing dose, while the contrast values were increased. For the contrast-to-noise ratio, a digressive course of the values as a function of the tube voltage was found. The visual evaluation of image quality showed the best evaluation of the structures at the lowest possible dose in the settings (44 kV, 3.36 mAs) with copper filtration and in the settings (44 kV, 1.56 mAs) without copper filtration. A maximum dose reduction from 8.29 µSv to 2.21 µSv (about 73%) was obtained. CONCLUSION: A dose reduction while preserving diagnostic image quality in a digital X-ray system is generally possible by reducing the tube voltage and simultaneous adaptation of the mAs settings.


Subject(s)
Lung/diagnostic imaging , Phantoms, Imaging , Radiation Dosage , Radiography, Thoracic/methods , Humans , Infant, Newborn
2.
Radiologe ; 60(10): 959-965, 2020 Oct.
Article in German | MEDLINE | ID: mdl-32495008

ABSTRACT

BACKGROUND: The entry of the new Radiation Protection Act and new Radiation Protection Regulation into force in Germany created many changes for radiology with regard to the old Radiation Protection Regulation and X­ray Regulation. OBJECTIVES: The substantial modifications in radiology regarding the areas of approval and notification procedures, teleradiology, screening, research and radon in the workplace are summarized. METHOD: Changes in the new Radiation Protection Act and Regulation compared to the old Radiation Protection Regulation and X­ray Regulation were evaluated. Thereby, the focus was on areas beyond the workflow in clinical routine. RESULTS AND CONCLUSION: The requirements for the approval and notification procedure have increased. For example, proof must be provided that a medical physics expert can be consulted. The establishment of deadlines for the process by the responsible authorities may accelerate the procedure and create planning certainty.


Subject(s)
Radiation Protection , Radiology , Teleradiology , Germany , Humans , Radiation Protection/legislation & jurisprudence , Radiography
3.
Radiologe ; 60(8): 721-728, 2020 Aug.
Article in German | MEDLINE | ID: mdl-32495010

ABSTRACT

BACKGROUND: On 31 December 2018, the new Radiation Protection Regulation came into effect in Germany and made the new Radiation Protection Act more concrete. The old Radiation Protection Regulation and X­ray Regulation have thereby been replaced. OBJECTIVES: The substantial modifications regarding the practical daily routine in radiology are summarized. METHODS: Modifications and innovations of the New Radiation Protection Act and Regulation compared to the old Radiation Protection Regulation and X­ray Regulation and accordances were evaluated. Thereby the main focus was in the relevance for workflow in clinical routine. RESULTS AND CONCLUSION: The new legislation contains a number of regulations that provide crucial tools for implementation of radiation protection, quality assurance, and dose optimization. However, this also requires additional time and personnel.


Subject(s)
Radiation Protection/legislation & jurisprudence , Radiology/organization & administration , Workflow , Germany , Humans
4.
J Math Biol ; 78(3): 579-606, 2019 02.
Article in English | MEDLINE | ID: mdl-30194480

ABSTRACT

The reproductive cycle of mono-ovulatory species such as cows or humans is known to show two or more waves of follicular growth and decline between two successive ovulations. Within each wave, there is one dominant follicle escorted by subordinate follicles of varying number. Under the surge of the luteinizing hormone a growing dominant follicle ovulates. Rarely the number of ovulating follicles exceeds one. In the biological literature, the change of hormonal concentrations and individually varying numbers of follicular receptors are made responsible for the selection of exactly one dominant follicle, yet a clear cause has not been identified. In this paper, we suggest a synergistic explanation based on competition, formulated by a parsimoniously defined system of ordinary differential equations (ODEs) that quantifies the time evolution of multiple follicles and their competitive interaction during one wave. Not discriminating between follicles, growth and decline are given by fixed rates. Competition is introduced via a growth-suppressing term, equally supported by all follicles. We prove that the number of dominant follicles is determined exclusively by the ratio of follicular growth and competition. This number turns out to be independent of the number of subordinate follicles. The asymptotic behavior of the corresponding dynamical system is investigated rigorously, where we demonstrate that the [Formula: see text]-limit set only contains fixed points. When also including follicular decline, our ODEs perfectly resemble ultrasound data of bovine follicles. Implications for the involved but not explicitly modeled hormones are discussed.


Subject(s)
Cattle/physiology , Models, Biological , Ovarian Follicle/physiology , Animals , Female , Follicle Stimulating Hormone/physiology , Humans , Kinetics , Mathematical Concepts , Ovulation/physiology
6.
Waste Manag Res ; 33(8): 715-22, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26081643

ABSTRACT

Plasma torch gasification (PTG) is currently researched as a technology for solid waste recovery. However, scientific studies based on evaluating its environmental implications considering the life cycle assessment (LCA) methodology are lacking. Therefore, this work is focused on comparing the environmental effect of the emissions of syngas combustion produced by refuse derived fuel (RDF) and PTG as alternative fuels, with that related to fossil fuel combustion in the cement industry. To obtain real data, a semi-industrial scale pilot plant was used to perform experimental trials on RDF-PTG.The results highlight that PTG for waste to energy recovery in the cement industry is environmentally feasible considering its current state of development. A reduction in every impact category was found when a total or partial substitution of alternative fuel for conventional fuel in the calciner firing (60 % of total thermal energy input) was performed. Furthermore, the results revealed that electrical energy consumption in PTG is also an important parameter from the LCA approach.


Subject(s)
Air Pollutants/analysis , Biofuels/analysis , Incineration , Refuse Disposal/methods , Solid Waste/analysis , Construction Industry , Environment , Pilot Projects
7.
J Cardiovasc Pharmacol ; 64(1): 69-78, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24621652

ABSTRACT

Pharmacological blockade of the mineralocorticoid receptor (MR) ameliorates end-organ damage in chronic heart failure. However, the clinical use of available steroidal MR antagonists is restricted because of concomitant hyperkalemia especially in patients with diminished kidney function. We have recently identified a novel nonsteroidal MR antagonist, finerenone, which uniquely combines potency and selectivity toward MR. Here, we investigated the tissue distribution and chronic cardiorenal end-organ protection of finerenone in comparison to the steroidal MR antagonist, eplerenone, in 2 different preclinical rat disease models. Quantitative whole-body autoradiography revealed that [C]-labeled finerenone equally distributes into rat cardiac and renal tissues. Finerenone treatment prevented deoxycorticosterone acetate-/salt-challenged rats from functional as well as structural heart and kidney damage at dosages not reducing systemic blood pressure. Finerenone reduced cardiac hypertrophy, plasma prohormone of brain natriuretic peptide, and proteinuria more efficiently than eplerenone when comparing equinatriuretic doses. In rats that developed chronic heart failure after coronary artery ligation, finerenone (1 mg·kg·d), but not eplerenone (100 mg·kg·d) improved systolic and diastolic left ventricular function and reduced plasma prohormone of brain natriuretic peptide levels. We conclude that finerenone may offer end-organ protection with a reduced risk of electrolyte disturbances.


Subject(s)
Heart Failure/prevention & control , Kidney Diseases/prevention & control , Mineralocorticoid Receptor Antagonists/pharmacology , Naphthyridines/pharmacology , Spironolactone/analogs & derivatives , Animals , Autoradiography , Cardiomegaly/prevention & control , Disease Models, Animal , Eplerenone , Male , Mineralocorticoid Receptor Antagonists/pharmacokinetics , Naphthyridines/pharmacokinetics , Natriuretic Peptide, Brain/blood , Peptide Fragments/blood , Rats , Rats, Sprague-Dawley , Rats, Wistar , Spironolactone/pharmacokinetics , Spironolactone/pharmacology , Tissue Distribution
9.
Nutrients ; 16(12)2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38931164

ABSTRACT

The quality-initiative analysis of weekly duplicate PEAPOD® body composition measurements was conducted from clinical practice (January to September 2021) on preterm and term infants without respiratory support. Statistical analysis, including regression analysis, Bland-Altman plots and cv-root-mean-square tests, was performed. A total of 188 duplicate (376 individual) measurements were collected from 119 infants (88 preterm, 31 term). The median absolute difference between duplicates was 31.5 g for fat-free mass (FFM). Linear correlation analysis showed R2 = 0.97 for FFM. The absolute differences in FFM and fat mass did not significantly correlate with increasing age. The %FFM differed (p = 0.02) across body weight groups of 1 kg < BW ≤ 2 kg (1.8%; IQR: 0.8, 3.6) and BW > 3 kg (0.9%; IQR: 0.3, 2.1). The median absolute differences were 1 g (IQR: 0.4, 3.1) for body weight and 5.6 mL (IQR: 2.1, 11.8) for body volume. Body volume estimation is charged with a constant absolute error, which is the main factor for differences between repeated body composition assessments. This error becomes more prominent in infants with lower body weights. Nevertheless, reproducibility of weekly PEAPOD testing is sufficient to monitor body compartment changes, offering a foundation for nutritional decisions in both preterm and term infants.


Subject(s)
Body Composition , Infant, Premature , Plethysmography , Humans , Infant, Newborn , Reproducibility of Results , Male , Female , Plethysmography/methods , Infant , Body Weight
10.
Soc Stud Sci ; : 3063127231205043, 2023 Nov 16.
Article in English | MEDLINE | ID: mdl-37974362

ABSTRACT

This article analyses how a recent idiom of innovation governance, 'responsible innovation', is enacted in practice, how this shapes innovation processes, and what aspects of innovation are left untouched. Within this idiom, funders typically focus on one point in an innovation system: researchers in projects. However, the more transformational aspirations of responsible innovation are circumscribed by this context. Adopting a mode of critique that assembles, this article considers some alternative approaches to governing the shared trajectories of science, technology, and society. Using the idea of institutional invention to focus innovation governance on four inflection points-agendas, calls, spaces, evaluation-would allow funding organizations and researchers to look 'beyond the project', developing new methods to unpack and reflect on assumed purposes of science, technology, and innovation, and to potentially reconfigure the institutions that condition scientific practice.

11.
Nat Commun ; 14(1): 4165, 2023 07 13.
Article in English | MEDLINE | ID: mdl-37443299

ABSTRACT

Intrinsically disordered regions (IDRs) are essential for membrane receptor regulation but often remain unresolved in structural studies. TRPV4, a member of the TRP vanilloid channel family involved in thermo- and osmosensation, has a large N-terminal IDR of approximately 150 amino acids. With an integrated structural biology approach, we analyze the structural ensemble of the TRPV4 IDR and the network of antagonistic regulatory elements it encodes. These modulate channel activity in a hierarchical lipid-dependent manner through transient long-range interactions. A highly conserved autoinhibitory patch acts as a master regulator by competing with PIP2 binding to attenuate channel activity. Molecular dynamics simulations show that loss of the interaction between the PIP2-binding site and the membrane reduces the force exerted by the IDR on the structured core of TRPV4. This work demonstrates that IDR structural dynamics are coupled to TRPV4 activity and highlights the importance of IDRs for TRP channel function and regulation.


Subject(s)
Cell Physiological Phenomena , TRPV Cation Channels , TRPV Cation Channels/metabolism , Protein Domains , Regulatory Sequences, Nucleic Acid , Lipids
12.
Sci Total Environ ; 866: 161220, 2023 Mar 25.
Article in English | MEDLINE | ID: mdl-36584954

ABSTRACT

To benefit allergy patients and the medical practitioners, pollen information should be available in both a reliable and timely manner; the latter is only recently possible due to automatic monitoring. To evaluate the performance of all currently available automatic instruments, an international intercomparison campaign was jointly organised by the EUMETNET AutoPollen Programme and the ADOPT COST Action in Munich, Germany (March-July 2021). The automatic systems (hardware plus identification algorithms) were compared with manual Hirst-type traps. Measurements were aggregated into 3-hourly or daily values to allow comparison across all devices. We report results for total pollen as well as for Betula, Fraxinus, Poaceae, and Quercus, for all instruments that provided these data. The results for daily averages compared better with Hirst observations than the 3-hourly values. For total pollen, there was a considerable spread among systems, with some reaching R2 > 0.6 (3 h) and R2 > 0.75 (daily) compared with Hirst-type traps, whilst other systems were not suitable to sample total pollen efficiently (R2 < 0.3). For individual pollen types, results similar to the Hirst were frequently shown by a small group of systems. For Betula, almost all systems performed well (R2 > 0.75 for 9 systems for 3-hourly data). Results for Fraxinus and Quercus were not as good for most systems, while for Poaceae (with some exceptions), the performance was weakest. For all pollen types and for most measurement systems, false positive classifications were observed outside of the main pollen season. Different algorithms applied to the same device also showed different results, highlighting the importance of this aspect of the measurement system. Overall, given the 30 % error on daily concentrations that is currently accepted for Hirst-type traps, several automatic systems are currently capable of being used operationally to provide real-time observations at high temporal resolutions. They provide distinct advantages compared to the manual Hirst-type measurements.


Subject(s)
Allergens , Hypersensitivity , Humans , Environmental Monitoring/methods , Pollen , Seasons , Poaceae , Betula
13.
FASEB J ; 25(3): 968-78, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21135038

ABSTRACT

Epidemiological studies exploring the connection between hypertension and cancer demonstrate a higher cancer incidence, especially of kidney cancer, and a higher cancer mortality in hypertensive patients. Hormones elevated in hypertension, i.e., aldosterone and angiotensin II, which exert genotoxic effects in vitro, could contribute to carcinogenesis in hypertension. The present study was conducted to investigate the possible DNA-damaging effect of aldosterone receptor activation in vivo. Crl:CD (Sprague-Dawley) rats were treated for 6 wk with desoxycorticosterone acetate (DOCA) and salt to induce a mineralocorticoid-dependent hypertension. DOCA-salt treatment caused increased blood pressure (+26 mmHg) compared to untreated rats, elevated markers of kidney failure (up to 62-fold for Kim-1), and the induction of several proinflammatory genes and proteins (up to 2.6-fold for tissue MCP-1). The mineralocorticoid receptor (MR) antagonist spironolactone (MR IC(50) 24 nM) and the novel nonsteroidal antagonist BR-4628 (MR IC(50) 28 nM) decreased these damage markers. DOCA-salt treatment also caused 8.8-fold increased structural DNA damage, determined with the comet assay, double-strand breaks (3.5-fold), detected immunohistochemically, and oxidative stress. Furthermore, the oxidatively modified mutagenic DNA base 7,8-dihydro-8-oxo-guanine (8-oxodG), quantified by LC-MS/MS, was almost 2-fold higher in DOCA-salt-treated kidneys. Our results suggest a mutagenic potential of high mineralocorticoid levels, frequent in hypertensive individuals.


Subject(s)
DNA Breaks, Double-Stranded , DNA Damage/physiology , Hypertension, Renal/metabolism , Hypertension, Renal/pathology , Receptors, Mineralocorticoid/metabolism , Animals , Apoptosis/drug effects , Apoptosis/physiology , Blood Pressure/physiology , Cell Division/drug effects , Cell Division/physiology , Desoxycorticosterone/toxicity , Disease Models, Animal , Guanine/analogs & derivatives , Guanine/metabolism , Hypertension, Renal/drug therapy , Kidney/pathology , Kidney/physiopathology , Male , Mineralocorticoid Receptor Antagonists/pharmacology , Mineralocorticoids/toxicity , Nephrectomy , Nephritis/drug therapy , Nephritis/metabolism , Nephritis/pathology , Oxidative Stress/physiology , Rats , Rats, Sprague-Dawley , Receptors, Mineralocorticoid/genetics , Spironolactone/pharmacology
14.
J Biol Chem ; 285(39): 29932-40, 2010 Sep 24.
Article in English | MEDLINE | ID: mdl-20650892

ABSTRACT

Limitations of current steroidal mineralocorticoid receptor (MR) antagonists have stimulated the search for a new generation of molecules. We screened for novel nonsteroidal compounds and identified MR antagonists derived from the chemical class of dihydropyridines. Chemical optimization resulted in BR-4628, which displays high in vitro and in vivo MR potency as well as selectivity with respect to the other steroid hormone receptors and the L-type calcium channel. Biochemical studies demonstrated that BR-4628 forms complexes with MR that do not promote the recruitment of transcriptional co-regulators. Docking experiments, using the crystal structure of the MR ligand-binding domain in an agonist conformation, revealed that BR-4628 accommodates in the MR ligand-binding cavity differently in comparison with the classical steroidal MR antagonists. An alanine scanning mutagenesis approach, based on BR-4628 docking, allowed identifying its anchoring mode within the ligand-binding cavity. Altogether, we propose that BR-4628 is a bulky antagonist that inactivates MR through a passive mechanism. It represents the prototype of a new class of MR antagonists.


Subject(s)
Dihydropyridines/pharmacology , Mineralocorticoid Receptor Antagonists , Amino Acid Substitution , Animals , Binding Sites , CHO Cells , Calcium Channels, L-Type/genetics , Calcium Channels, L-Type/metabolism , Cricetinae , Cricetulus , Crystallography, X-Ray , Dihydropyridines/chemistry , Drug Evaluation, Preclinical , Humans , Ligands , Mutation, Missense , Receptors, Mineralocorticoid/genetics , Receptors, Mineralocorticoid/metabolism
15.
Kidney Int ; 80(11): 1182-97, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21814170

ABSTRACT

Recent studies have shown renoprotective effects of the peroxisome proliferator-activated receptor-α (PPAR-α), but its role in kidney fibrosis is unknown. In order to gain insight into this, we examined the effect of a novel PPAR-α agonist, BAY PP1, in two rat models of renal fibrosis: unilateral ureteral obstruction and the 5/6 nephrectomy. In healthy animals, PPAR-α was expressed in tubular but not in interstitial cells. Upon induction of fibrosis, PPAR-α was significantly downregulated, and treatment with BAY PP1 significantly restored its expression. During ureteral obstruction, treatment with BAY PP1 significantly reduced tubulointerstitial fibrosis, proliferation of interstitial fibroblasts, and TGF-ß(1) expression. Treatment with a less potent PPAR-α agonist, fenofibrate, had no effects. Treatment with BAY PP1, initiated in established disease in the 5/6 nephrectomy, halted the decline of renal function and significantly ameliorated renal fibrosis. In vitro, BAY PP1 had no direct effect on renal fibroblasts but reduced collagen, fibronectin, and TGF-ß(1) expression in tubular cells. Conditioned media of BAY PP1-treated tubular cells reduced fibroblast proliferation. Thus, renal fibrosis is characterized by a reduction of PPAR-α expression, and treatment with BAY PP1 restores PPAR-α expression and ameliorates renal fibrosis by modulating the cross-talk between tubular cells and fibroblasts. Hence, potent PPAR-α agonists might be useful in the treatment of renal fibrosis.


Subject(s)
3-Mercaptopropionic Acid/analogs & derivatives , Fibrosis/prevention & control , Kidney Diseases/drug therapy , Peroxisome Proliferator-Activated Receptors/agonists , Pyrimidines/therapeutic use , 3-Mercaptopropionic Acid/pharmacology , 3-Mercaptopropionic Acid/therapeutic use , Animals , Cell Proliferation/drug effects , Fibrosis/drug therapy , Kidney Diseases/pathology , Kidney Tubules/pathology , Nephrectomy , Protective Agents , Pyrimidines/pharmacology , Rats , Treatment Outcome , Ureteral Obstruction/drug therapy
16.
Front Endocrinol (Lausanne) ; 12: 613048, 2021.
Article in English | MEDLINE | ID: mdl-33790856

ABSTRACT

New approaches to ovarian stimulation protocols, such as luteal start, random start or double stimulation, allow for flexibility in ovarian stimulation at different phases of the menstrual cycle. It has been proposed that the success of these methods is based on the continuous growth of multiple cohorts ("waves") of follicles throughout the menstrual cycle which leads to the availability of ovarian follicles for ovarian controlled stimulation at several time points. Though several preliminary studies have been published, their scientific evidence has not been considered as being strong enough to integrate these results into routine clinical practice. This work aims at adding further scientific evidence about the efficiency of variable-start protocols and underpinning the theory of follicular waves by using mathematical modeling and numerical simulations. For this purpose, we have modified and coupled two previously published models, one describing the time course of hormones and one describing competitive follicular growth in a normal menstrual cycle. The coupled model is used to test ovarian stimulation protocols in silico. Simulation results show the occurrence of follicles in a wave-like manner during a normal menstrual cycle and qualitatively predict the outcome of ovarian stimulation initiated at different time points of the menstrual cycle.


Subject(s)
Models, Theoretical , Ovulation Induction/methods , Ovulation Induction/trends , Computer Simulation , Female , Fertility Agents, Female/administration & dosage , Fertility Agents, Female/pharmacokinetics , Humans , Menstrual Cycle/physiology , Ovarian Follicle/cytology , Ovarian Follicle/physiology , Pharmacokinetics , Therapies, Investigational/methods , Therapies, Investigational/trends
17.
Biochem Biophys Res Commun ; 394(1): 233-9, 2010 Mar 26.
Article in English | MEDLINE | ID: mdl-20206126

ABSTRACT

Elevated plasma levels of C-reactive protein (CRP), the prototype acute-phase protein (APP), are predictive for future cardiovascular events. Controversial evidence suggests that CRP may play a causal role in cardiovascular disease. CRP synthesis inhibition is a potential approach for reducing cardiovascular mortality. We show here that endogenous and plant-derived inhibitors of the Na(+)/K(+)-ATPase, i.e. the cardiac glycosides ouabain and digitoxin, inhibit IL-1beta- and IL-6-induced APP expression in human hepatoma cells and primary human hepatocytes (PHH) at nanomolar concentrations. Inhibition is demonstrated on transcriptional and on protein level. The molecular target of cardiac glycosides, i.e. the alpha1 subunit of the Na(+)/K(+)-ATPase, is strongly expressed in human hepatocytes. Inhibition of APP synthesis correlates with the potency of cardiac glycosides at the Na(+)/K(+)-ATPase. The trigger for APP expression inhibition is an increase in intracellular calcium since the calcium ionophore calcimycin is also active. Qualified specificity of oubain for hepatocellular APP synthesis inhibition is demonstrated by lack of effectivity on IL-1beta-induced IL-6 release from primary human coronary artery smooth muscle cells. The inhibitory activity of cardiac glycosides on CRP expression may have important implications for the treatment of cardiovascular disease. Cardiac glycosides may be used for CRP synthesis inhibition in the future.


Subject(s)
C-Reactive Protein/antagonists & inhibitors , Cardiac Glycosides/pharmacology , Hepatocytes/drug effects , Transcription, Genetic/drug effects , Adult , C-Reactive Protein/biosynthesis , C-Reactive Protein/genetics , Calcium/metabolism , Cell Line, Tumor , Cells, Cultured , Digitoxin/pharmacology , Female , Hepatocytes/metabolism , Humans , Interleukin-1beta/pharmacology , Interleukin-6/pharmacology , Male , Middle Aged , Ouabain/pharmacology , Promoter Regions, Genetic/drug effects
18.
Arch Dis Child Fetal Neonatal Ed ; 105(2): 190-195, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31248963

ABSTRACT

OBJECTIVE: To determine if survival rates of preterm infants receiving active perinatal care improve over time. DESIGN: The German Neonatal Network is a cohort study of preterm infants with birth weight <1500 g. All eligible infants receiving active perinatal care are registered. We analysed data of patients discharged between 2011 and 2016. SETTING: 43 German level III neonatal intensive care units (NICUs). PATIENTS: 8222 preterm infants with a gestational age between 22/0 and 28/6 weeks who received active perinatal care. INTERVENTIONS: Participating NICUs were grouped according to their specific survival rate from 2011 to 2013 to high (percentile >P75), intermediate (P25-P75) and low (

Subject(s)
Infant, Extremely Premature , Intensive Care Units, Neonatal/statistics & numerical data , Perinatal Care/methods , Perinatal Care/statistics & numerical data , Perinatal Mortality/trends , Cause of Death , Comorbidity , Female , Gestational Age , Health Status , Humans , Infant , Infant, Newborn , Infant, Very Low Birth Weight , Male , Prospective Studies , Quality Improvement , Risk Factors , Sex Factors , Tertiary Care Centers
19.
Circulation ; 118(20): 2081-90, 2008 Nov 11.
Article in English | MEDLINE | ID: mdl-18955668

ABSTRACT

BACKGROUND: Inhibition of tyrosine kinases, including platelet-derived growth factor receptor, can reduce pulmonary arterial pressure in experimental and clinical pulmonary hypertension. We hypothesized that inhibition of the serine/threonine kinases Raf-1 (also termed c-Raf) and b-Raf in addition to inhibition of tyrosine kinases effectively controls pulmonary vascular and right heart remodeling in pulmonary hypertension. METHODS AND RESULTS: We investigated the effects of the novel multikinase inhibitor sorafenib, which inhibits tyrosine kinases as well as serine/threonine kinases, in comparison to imatinib, a tyrosine kinase inhibitor, on hemodynamics, pulmonary and right ventricular (RV) remodeling, and downstream signaling in experimental pulmonary hypertension. Fourteen days after monocrotaline injection, male rats were treated orally for another 14 days with sorafenib (10 mg/kg per day), imatinib (50 mg/kg per day), or vehicle (n=12 to 16 per group). RV systolic pressure was decreased to 35.0+/-1.5 mm Hg by sorafenib and to 54.0+/-4.4 mm Hg by imatinib compared with placebo (82.9+/-6.0 mm Hg). In parallel, both sorafenib and imatinib reduced RV hypertrophy and pulmonary arterial muscularization. The effects of sorafenib on RV systolic pressure and RV mass were significantly greater than those of imatinib. Sorafenib prevented phosphorylation of Raf-1 and suppressed activation of the downstream ERK1/2 signaling pathway in RV myocardium and the lungs. In addition, sorafenib but not imatinib antagonized vasopressin-induced hypertrophy of the cardiomyoblast cell line H9c2. CONCLUSIONS: The multikinase inhibitor sorafenib prevents pulmonary remodeling and improves cardiac and pulmonary function in experimental pulmonary hypertension. Sorafenib exerts direct myocardial antihypertrophic effects, which appear to be mediated via inhibition of the Raf kinase pathway. The combined inhibition of tyrosine and serine/threonine kinases may provide an option to treat pulmonary arterial hypertension and associated right heart remodeling.


Subject(s)
Benzenesulfonates/pharmacology , Hypertension, Pulmonary/physiopathology , Protein Kinase Inhibitors/pharmacology , Protein-Tyrosine Kinases/antagonists & inhibitors , Pyridines/pharmacology , Ventricular Remodeling/drug effects , raf Kinases/antagonists & inhibitors , Animals , Benzamides , Blood Pressure/drug effects , Disease Progression , Extracellular Signal-Regulated MAP Kinases/metabolism , Heart/drug effects , Heart/physiopathology , Heart Ventricles , Imatinib Mesylate , Lung/drug effects , Lung/physiopathology , Male , Niacinamide/analogs & derivatives , Phenylurea Compounds , Phosphorylation/drug effects , Piperazines/pharmacology , Proto-Oncogene Proteins c-raf/antagonists & inhibitors , Pulmonary Artery/drug effects , Pulmonary Artery/physiopathology , Pyrimidines/pharmacology , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects , Sorafenib
20.
Mol Cancer Res ; 6(7): 1250-8, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18644987

ABSTRACT

In addition to repressing ERBB2 promoter function, histone deacetylase (HDAC) inhibitors induce the accelerated decay of mature ERBB2 transcripts; the mechanism mediating this transcript destabilization is unknown but depends on the 3' untranslated region (UTR) of ERBB2 mRNA. Using ERBB2-overexpressing human breast cancer cells (SKBR3), the mRNA stability factor HuR was shown to support ERBB2 transcript integrity, bind and endogenously associate with a conserved U-rich element within the ERBB2 transcript 3' UTR, coimmunoprecipitate with RNA-associated HDAC activity, and colocalize with HDAC6. HDAC6 also coimmunoprecipitates with HuR in an RNA-dependent manner and within 6 hours of exposure to a pan-HDAC inhibitor dose, that does not significantly alter cytosolic HuR levels or HuR binding to ERBB2 mRNA. Cellular ERBB2 transcript levels decline while remaining physically associated with HDAC6. Knockdown of HDAC6 protein by small interfering RNA partially suppressed the ERBB2 transcript decay induced by either pan-HDAC or HDAC6-selective enzymatic inhibitors. Three novel hydroxamates, ST71, ST17, and ST80 were synthesized and shown to inhibit HDAC6 with 14-fold to 31-fold greater selectivity over their binding and inhibition of HDAC1. Unlike more potent pan-HDAC inhibitors, these HDAC6-selective inhibitors produced dose-dependent growth arrest of ERBB2-overexpressing breast cancer cells by accelerating the decay of mature ERBB2 mRNA without repressing ERBB2 promoter function. In sum, these findings point to the therapeutic potential of HuR and HDAC6-selective inhibitors, contrasting ERBB2 stability effects induced by HDAC6 enzymatic inhibition and HDAC6 protein knockdown, and show that ERBB2 transcript stability mechanisms include exploitable targets for the development of novel anticancer therapies.


Subject(s)
3' Untranslated Regions/genetics , ELAV Proteins/genetics , Histone Deacetylases/genetics , RNA Stability , Receptor, ErbB-2/genetics , Base Sequence , Cell Line, Tumor , Cytosol/drug effects , Cytosol/metabolism , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , Histone Deacetylase 6 , Humans , Hydroxamic Acids/chemistry , Hydroxamic Acids/pharmacology , Molecular Sequence Data , Niacinamide/analogs & derivatives , Niacinamide/chemistry , Niacinamide/pharmacology , Promoter Regions, Genetic/genetics , Protein Transport/drug effects , RNA Stability/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptor, ErbB-2/metabolism
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