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61.
Meike M.C. Hirdes Tom P.V.M. de Jong Pieter Dik Marianne A.W. Vijverberg Rafal Chrzan Aart J. Klijn 《Journal of pediatric urology》2010,6(4):372-375
PurposeTo investigate systematically the length of the urethra in girls with lower urinary tract symptoms.Materials and methodsIn a group of 121 consecutive girls presented at a tertiary referral clinic for urinary incontinence or recurrent urinary tract infections, urethral length was measured by perineal ultrasound. The urethra was measured with the patient in supine position without anesthesia. Mean age of the patients was 7.8 (0–15) years.ResultsAverage urethral length was 26 mm. Minimum length was 12 mm, measured in a 5-year-old girl with dribbling incontinence. Maximum measured length was 40 mm in a 15-year-old girl. In four girls (3.3%), aged 1–10 years (mean 6.3), a short urethra was detected, with measured lengths of 12 and 14 mm. All four had normal genitalia, and were referred with therapy-resistant urinary incontinence or urinary tract infections. A gradual increase in average urethral length was measured from 23 mm at birth to 32 mm at 15 years.ConclusionUrethral length can be measured accurately by ultrasound. Although a short urethral length is rarely detected by ultrasound in girls with incontinence, it may be associated with therapy-resistant incontinence. In such cases, different treatment options are available. 相似文献
62.
Olaf Holz Karsten Heusser Meike Müller Horst Windt Katharina Schwarz Christoph Schindler 《Journal of toxicology and environmental health. Part A》2018,81(13):576-588
Increased adverse health effects in older subjects due to exposure to ambient air pollutants may be related to the inflammatory response induced by these contaminants. The aim of this study was to assess airway and systemic inflammatory responses in older healthy subjects to a controlled experimental exposure with spark-generated elemental carbon black ultrafine particles (cbUFPs) and ozone (O3). Twenty healthy subjects, age 52–75 years, were exposed on three occasions separated by at least 8 weeks. The exposures to filtered air (FA), to cbUFP (50 μg/m3), or to cbUFP in combination with 250 ppb ozone (cbUFP + O3) for 3 h with intermittent exercise were performed double blind, and in random order. Sputum and blood samples were collected 3.5 h after each exposure. Exposure to cbUFP + O3 significantly increased plasma club cell protein 16 (CC16), the number of sputum cells, the number and percent of sputum neutrophils, and sputum interleukin 6 and matrix metalloproteinase 9. Exposure to cbUFP alone exerted no marked effect, except for an elevation in sputum neutrophils in a subgroup of 13 subjects that displayed less than 65% sputum neutrophils after FA exposure. None of the inflammatory markers was correlated with age, and serum cardiovascular risk markers were not markedly affected by cbUFP or cbUFP + O3. Exposure to cbUFP+O3 induced a significant airway and systemic inflammatory response in older healthy volunteer subjects. The effects induced by cbUFP alone suggest that the inflammation was predominantly mediated by O3, although one cannot rule out that the interaction of cbUFP and O3 played a role. 相似文献
63.
In this paper, we describe a peptide library designed by computational modelling and the selection of two peptide sequences showing affinity towards the mycotoxin, ochratoxin A (OTA). A virtual library of 20 natural amino acids was used as building blocks to design a short peptide library against ochratoxin A template using the de novo design program, LeapFrog, and the dynamic modelling software, FlexiDock. Peptide sequences were ranked according to calculated binding scores in their capacity to bind to ochratoxin A. Two high scoring peptides with the sequences N''-Cys-Ser-Ile-Val-Glu-Asp-Gly-Lys-C'' (octapeptide) and N''-Gly-Pro-Ala-Gly-Ile-Asp-Gly-Pro-Ala-Gly-Ile-Arg-Cys-C'' (13-mer) were selected for synthesis from the resulting database. These synthesized peptides were characterized using a microtitre plate-based binding assay and a surface plasmon resonance biosensor (Biacore 3000). The binding assay confirmed that both de novo designed peptides did bind to ochratoxin A in vitro. SPR analysis confirmed that the peptides bind to ochratoxin A, with calculated KD values of ~15.7 μM (13-mer) and ~11.8 μM (octamer). The affinity of the peptides corresponds well with the molecular modelling results, as the 13-mer peptide affinity is about 1.3-times weaker than the octapeptide; this is in accordance with the binding energy values modelled by FlexiDock. This work illustrates the potential of using computational modelling to design a peptide sequence that exhibits in vitro binding affinity for a small molecular weight toxin. 相似文献
64.
Oxidative stress and mitochondrial aldehyde dehydrogenase activity: a comparison of pentaerythritol tetranitrate with other organic nitrates 总被引:8,自引:0,他引:8
Daiber A Oelze M Coldewey M Bachschmid M Wenzel P Sydow K Wendt M Kleschyov AL Stalleicken D Ullrich V Mülsch A Münzel T 《Molecular pharmacology》2004,66(6):1372-1382
Mitochondrial aldehyde dehydrogenase (ALDH-2) was recently identified to be essential for the bioactivation of glyceryl trinitrate (GTN). Here we assessed whether other organic nitrates are bioactivated by a similar mechanism. The ALDH-2 inhibitor benomyl reduced the vasodilator potency, but not the efficacy, of GTN, pentaerythritol tetranitrate (PETN), and pentaerythritol trinitrate in phenylephrine-constricted rat aorta, whereas vasodilator responses to isosorbide dinitrate, isosorbide-5-mononitrate, pentaerythritol dinitrate, pentaerythritol mononitrate, and the endothelium-dependent vasodilator acetylcholine were not affected. Likewise, benomyl decreased GTN- and PETN-elicited phosphorylation of the cGMP-activated protein kinase substrate vasodilator-stimulated phosphoprotein (VASP) but not that elicited by other nitrates. The vasodilator potency of organic nitrates correlated with their potency to inhibit ALDH-2 dehydrogenase activity in mitochondria from rat heart and increase mitochondrial superoxide formation, as detected by chemiluminescence. In contrast, mitochondrial ALDH-2 esterase activity was not affected by PETN and its metabolites, whereas it was inhibited by benomyl, GTN applied in vitro and in vivo, and some sulfhydryl oxidants. The bioactivation-related metabolism of GTN to glyceryl-1,2-dinitrate by isolated RAW macrophages was reduced by the ALDH-2 inhibitors benomyl and daidzin, as well as by GTN at concentrations >1 microM. We conclude that mitochondrial ALDH-2, specifically its esterase activity, is required for the bioactivation of the organic nitrates with high vasodilator potency, such as GTN and PETN, but not for the less potent nitrates. It is interesting that ALDH-2 esterase activity was inhibited by GTN only, not by the other nitrates tested. This difference might explain why GTN elicits mitochondrial superoxide formation and nitrate tolerance with the highest potency. 相似文献
65.
Pauline H. Croll Daniel Bos Meike W. Vernooij Banafsheh Arshi Frank R. Lin Robert J. Baatenburg de Jong M. Arfan Ikram André Goedegebure Maryam Kavousi 《Journal of the American Medical Directors Association》2019,20(12):1617-1622.e1
ObjectivesCardiovascular disease may be linked to hearing loss through narrowing of the nutrient arteries of the cochlea, but large-scale population-based evidence for this association remains scarce. We investigated the association of carotid atherosclerosis as a marker of generalized cardiovascular disease with hearing loss in a population-based cohort.DesignCross-sectional.SettingA population-based cohort study.Participants3724 participants [mean age: 65.5 years, standard deviation (SD): 7.5, 55.4% female].MethodsUltrasound and pure-tone audiograms to assess carotid atherosclerosis and hearing loss.ResultsWe investigated associations of carotid plaque burden and carotid intima-media thickness (IMT) (overall and side-specific carotid atherosclerosis) with hearing loss (in the best hearing ear and side-specific hearing loss) using multivariable linear and ordinal regression models. We found that higher maximum IMT was related to poorer hearing in the best hearing ear [difference in decibel hearing level per 1-mm increase in IMT: 2.09 dB, 95% confidence interval (CI): 0.08, 4.10]. Additionally, third and fourth quartile plaque burden as compared to first quartile was related to poorer hearing in the best hearing ear (difference: 1.06 dB, 95% CI: 0.04, 2.08; and difference: 1.55 dB, 95% CI: 0.49, 2.60, respectively). Larger IMT (difference: 2.97 dB, 95% CI: 0.79, 5.14), third quartile plaque burden compared to first quartile (difference: 1.24 dB, 95% CI: 0.14, 2.35), and fourth plaque quartile compared to first quartile (difference: 2.12 dB, 95% CI: 0.98, 3.26) in the right carotid were associated with poorer hearing in the right ear.Conclusions and ImplicationsCarotid atherosclerosis is associated with poorer hearing in older adults, almost exclusively with poorer hearing in the right ear. Based on our results, it seems that current therapies for the prevention of cardiovascular disease may also prove beneficial for hearing loss in older adults by promoting and maintaining inner ear health. 相似文献
66.
67.
Florian Eisel Meike Boosen Martina Beck Heinrich Heide Ilka Wittig Karl-Friedrich Beck Josef Pfeilschifter 《Biochemical pharmacology》2013,85(1):101-108
Inflammatory glomerular kidney diseases are often accompanied with a massive production of reactive oxygen species (ROS) that affect the function of the glomerular filtration barrier and contribute to mesangiolysis via the induction of cell death in mesangial cells. Intriguingly, ROS also trigger fine-tuned signalling processes that affect gene expression and cell proliferation or migration. To define such redox-driven signalling devices, a proteomics approach was performed to identify the formation of protein complexes induced by ROS. To this end, protein lysates of human podocytes were treated with or without hydrogen peroxide (250 μM). Thereafter cell lysates were subjected to diagonal 2D gel electrophoresis and putative redox-affected proteins were analysed by MS/MS analysis. Among others, the regulatory subunit of protein kinase A (PKA) could be identified that forms homodimers under oxidative conditions. To evaluate whether ROS dependent dimerization of PKA also occurs in a more physiological setting, rat mesangial cells were treated with platelet-derived growth factor-BB (PDGF-BB) to induce ROS formation. This regimen resulted in a redox dependent dimerization of the R-subunits of PKA. To demonstrate whether PDGF-BB induced ROS formation affects PKA dependent pathways, the effects of PDGF-BB on phosphorylation of serine 157 of vasodilator stimulated protein (VASP) a classical target of PKA were analysed. Interestingly PDGF-BB induced VASP phosphorylation in a ROS dependent manner but independent of changes in cAMP levels. Taken together, we demonstrate a redox-mediated activation of PKA by PDGF-BB thus highlighting a physiological role of ROS as regulator of PKA activity in rat mesangial cells. 相似文献
68.
Bernd Bellmann Hartwig Muhle Otto Creutzenberg Heinrich Ernst Meike Müller David M. Bernstein 《Inhalation toxicology》2013,25(12):1147-1177
This 3-mo inhalation study investigated the biological effects of a special-purpose glass microfiber (E-glass microfiber), the stone wool fiber MMVF21, and a new high-temperature application fiber (calcium-magnesium-silicate fiber, CMS) in Wistar rats. Rats were exposed 6 h/day, 5 days/wk for 3 mo to fiber aerosol concentrations of approximately 15, 50, and 150 fibers/ml (fiber length >20 µm) for E-glass microfiber and MMVF21. For the CMS fiber only the highest exposure concentration was used. During a 3-mo postexposure period, recovery effects were studied. In the highest exposure concentration groups, gravimetric concentrations were 17.2 mg/m 3 for E-glass microfiber, 37 mg/m 3 for MMVF21, and 49.5 mg/m 3 for the CMS fiber. After 3 mo of exposure, lung retention of fibers longer than 20 µm per lung was 17 × 10 6 for E-glass microfiber, 5.7 × 10 6 for MMVF21, and 0.88 × 10 6 for CMS. After 3 mo of recovery the concentration of the long fiber fraction was decreased to 38.4%, 63.9%, and 3.0% compared to original lung burden for the E-glass microfiber, MMVF21, and CMS, respectively. Biological effects measured included inflammatory and proliferative potential, histopathology lesions, and the persistence of these effects over a recovery period of 3 mo. Generally, observed effects were higher for E-glass microfiber when compared to MMVF21. The following clear dose-dependent effects on E-glass microfiber and MMVF21 exposure were observed as main findings of the study: increase in lung weight, in measured biochemical parameters and polymorphonuclear leukocytes (PMN) in the bronchoalveolar lavage fluid (BALF), in cell proliferation (BrdU-response) of terminal bronchiolar epithelium, and in interstitial fibrosis. The values observed in the proliferation assay on the carcinogenic E-glass microfiber indicate that this assay has an important predictive value with regards to potential carcinogenicity. Surprisingly, for the biosoluble CMS fiber, fibrogenic potential was detected in this study. The results of the CMS exposure group indicate that effects may be dominated by the presence of nonfibrous particles and that fibrosis may not be a predictor of carcinogenic activity of fiber samples, if the fiber preparation contains a significant fraction of nonfibrous particles. In summary, this study demonstrates the importance of fiber dust contamination by granular components. For future subchronic studies a longer posttreatment observation period would be advisable. 相似文献
69.
Structural investigations on lipid nanoparticles containing high amounts of lecithin. 总被引:4,自引:0,他引:4
Martin Alexander Schubert Meike Harms Christel Charlotte Müller-Goymann 《European journal of pharmaceutical sciences》2006,27(2-3):226-236
Solid lipid nanoparticles (SLN), an alternative colloidal drug delivery system to polymer nanoparticles, emulsions and liposomes, possess inherent low incorporation rates resulting from the crystalline structure of the solid lipid. To increase the drug loading capacity of SLN, matrix modification by incorporation of the amphiphilic lipid lecithin within the lipid matrices has been proposed as a promising alternative. The objective of this work is to investigate the effects of the lecithin on the microstructure of matrix modified SLN. In addition, these systems were checked for the existence of aggregates like mixed micelles, liposomes, etc., which could possibly be formed by lecithin leakage into the aqueous phase during the preparation process. For this purpose, laser diffraction, photon correlation spectroscopy (PCS), small angle X-ray scattering (SAXS), nuclear magnetic resonance (NMR) and transmission electron microscopy (TEM) were performed to investigate the structure, mobility, and molecular environment of the compounds. Lecithin incorporation within the lipid matrices resulted in a concentration dependent decrease in particle size up to a critical concentration of 30%. Lecithin incorporation up to 50% was investigated but caused no further particle size decrease. TEM revealed anisometrical and crystalline platelets of ellipsoidal to disc-like shape. Furthermore, SAXS and TEM showed no signs of lecithin and nonionic emulsifier derived aggregates in the aqueous phase. This points in agreement with NMR measurements to a strong attachment of both substances to the SLN surfaces. The proposed structure of the particles after melt emulsification consists of two different layers: a crystalline triglyceride-rich core is covered in dependence of the lecithin content either by a monomolecular or multimolecular lecithin/Solutol HS15 (SOL) layer. 相似文献
70.
Gunnet JW Wines P Xiang M Rybczynski P Andrade-Gordon P de Garavilla L Parry TJ Cheung WM Minor L Demarest KT Maryanoff BE Damiano BP 《European journal of pharmacology》2008,590(1-3):333-342
The dysregulation of arginine vasopressin (AVP) release and activation of vasopressin V(1A) and V(2) receptors may play a role in disease. The in vitro and in vivo pharmacology of RWJ-676070, a potent, balanced antagonist of both the V(1A) and V(2) receptors is described. RWJ-676070 binding and intracellular functional antagonist activity was characterized using cells expressing V(1A), V(1B) or V(2) receptors. Its inhibition of V(1A) receptor-mediated contraction of vascular rings and platelet aggregation was determined. V(2) receptor-medated aquaresis was determined in rats, dogs and monkeys. V(1A) receptor-mediated inhibitory activity was assessed in vivo in a vasopressin-induced hypertension model and in normotensive rats and in two hypertensive rat models. RWJ-676070 inhibited AVP binding to human V(1A) and V(2) receptors (Ki=1 and 14 nM, respectively). RWJ-676070 inhibited V(1A) receptor-induced intracellular calcium mobilization and V(2) receptor-induced cAMP accumulation with Ki values of 14 nM and 13 nM, respectively. The compound was slightly less potent against rat V(1A) receptors. RWJ-676070 inhibited V(1A) receptor-mediated vasoconstriction in rat and dog vascular rings and AVP-induced human platelet aggregation. Dose dependent aquaresis was demonstrated in rats, dogs and monkeys following oral administration. RWJ-676070 inhibited AVP-induced hypertension in rats but had no effect on arterial pressure in normotensive and spontaneously hypertensive rats but did decrease arterial pressure in Dahl, salt-sensitive hypertensive rats. RWJ-676070 is a new, potent antagonist of V(1A) and V(2) receptors that may be useful for treatment of diseases benefiting from balanced inhibition of both V(1A) and V(2) receptors. 相似文献