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Discovery of retinoic acid receptor agonists as proliferators of cardiac progenitor cells through a phenotypic screening approach. Stem Cells Transl Med 2019; 9:47-60. [PMID: 31508905 PMCID: PMC6954720 DOI: 10.1002/sctm.19-0069] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 08/12/2019] [Indexed: 12/13/2022] Open
Abstract
Identification of small molecules with the potential to selectively proliferate cardiac progenitor cells (CPCs) will aid our understanding of the signaling pathways and mechanisms involved and could ultimately provide tools for regenerative therapies for the treatment of post‐MI cardiac dysfunction. We have used an in vitro human induced pluripotent stem cell‐derived CPC model to screen a 10,000‐compound library containing molecules representing different target classes and compounds reported to modulate the phenotype of stem or primary cells. The primary readout of this phenotypic screen was proliferation as measured by nuclear count. We identified retinoic acid receptor (RAR) agonists as potent proliferators of CPCs. The CPCs retained their progenitor phenotype following proliferation and the identified RAR agonists did not proliferate human cardiac fibroblasts, the major cell type in the heart. In addition, the RAR agonists were able to proliferate an independent source of CPCs, HuES6. The RAR agonists had a time‐of‐differentiation‐dependent effect on the HuES6‐derived CPCs. At 4 days of differentiation, treatment with retinoic acid induced differentiation of the CPCs to atrial cells. However, after 5 days of differentiation treatment with RAR agonists led to an inhibition of terminal differentiation to cardiomyocytes and enhanced the proliferation of the cells. RAR agonists, at least transiently, enhance the proliferation of human CPCs, at the expense of terminal cardiac differentiation. How this mechanism translates in vivo to activate endogenous CPCs and whether enhancing proliferation of these rare progenitor cells is sufficient to enhance cardiac repair remains to be investigated.
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Neuropeptide 26RFa (QRFP) is a key regulator of glucose homeostasis and its activity is markedly altered in obese/hyperglycemic mice. Am J Physiol Endocrinol Metab 2019; 317:E147-E157. [PMID: 31084498 DOI: 10.1152/ajpendo.00540.2018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Recent studies have shown that the hypothalamic neuropeptide 26RFa regulates glucose homeostasis by acting as an incretin and increasing insulin sensitivity. In this study, we further characterized the role of the 26RFa/GPR103 peptidergic system in the global regulation of glucose homeostasis using a 26RFa receptor antagonist and also assessed whether a dysfunction of the 26RFa/GPR103 system occurs in obese hyperglycemic mice. First, we demonstrate that administration of the GPR103 antagonist reduces the global glucose-induced incretin effect and insulin sensitivity whereas, conversely, administration of exogenous 26RFa attenuates glucose-induced hyperglycemia. Using a mouse model of high-fat diet-induced obesity and hyperglycemia, we found a loss of the antihyperglcemic effect and insulinotropic activity of 26RFa, accompanied with a marked reduction of its insulin-sensitive effect. Interestingly, this resistance to 26RFa is associated with a downregulation of the 26RFa receptor in the pancreatic islets, and insulin target tissues. Finally, we observed that the production and release kinetics of 26RFa after an oral glucose challenge is profoundly altered in the high-fat mice. Altogether, the present findings support the view that 26RFa is a key regulator of glucose homeostasis whose activity is markedly altered under obese/hyperglycemic conditions.
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Identification of Mineralocorticoid Receptor Modulators with Low Impact on Electrolyte Homeostasis but Maintained Organ Protection. J Med Chem 2018; 62:1385-1406. [DOI: 10.1021/acs.jmedchem.8b01523] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Structural Characterization of Agonist Binding to Protease-Activated Receptor 2 through Mutagenesis and Computational Modeling. ACS Pharmacol Transl Sci 2018; 1:119-133. [PMID: 32219208 DOI: 10.1021/acsptsci.8b00019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Indexed: 12/26/2022]
Abstract
Protease-activated receptor 2 (PAR2) is a G-protein-coupled receptor that is activated by proteolytic cleavage of its N-terminus. The unmasked N-terminal peptide then binds to the transmembrane bundle, leading to activation of intracellular signaling pathways associated with inflammation and cancer. Recently determined crystal structures have revealed binding sites of PAR2 antagonists, but the binding mode of the peptide agonist remains unknown. In order to generate a model of PAR2 in complex with peptide SLIGKV, corresponding to the trypsin-exposed tethered ligand, the orthosteric binding site was probed by iterative combinations of receptor mutagenesis, agonist ligand modifications, and data-driven structural modeling. Flexible-receptor docking identified a conserved binding mode for agonists related to the endogenous ligand that was consistent with the experimental data and allowed synthesis of a novel peptide (1-benzyl-1H[1,2,3]triazole-4-yl-LIGKV) with functional potency higher than that of SLIGKV. The final model may be used to understand the structural basis of PAR2 activation and in virtual screens to identify novel agonists and competitive antagonists. The combined experimental and computational approach to characterize agonist binding to PAR2 can be extended to study the many other G protein-coupled receptors that recognize peptides or proteins.
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Phenotypic Screen for Cardiac Regeneration Identifies Molecules with Differential Activity in Human Epicardium-Derived Cells versus Cardiac Fibroblasts. ACS Chem Biol 2017; 12:132-141. [PMID: 28103692 DOI: 10.1021/acschembio.6b00683] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Activation and proliferation of resident cardiac progenitor cells has therapeutic potential to repair the heart after injury. However, research has been impeded by a lack of well-defined and characterized cell sources and difficulties in translation to screening platforms. Here, we describe the development, validation, and use of a 384-well phenotypic assay in primary human epicardium-derived cells (EPDCs) to identify compounds that induce proliferation while maintaining the progenitor phenotype. Using this assay, we screened 7400 structurally diverse compounds where greater than 90% are biologically annotated and known to modulate a broad range of biological targets. From the primary screen, we identified and validated hits and expanded upon the lead molecules of interest. A counterscreen was developed in human cardiac fibroblasts to filter out compounds with a general proliferative effect, after which the activity of selected molecules was confirmed across multiple EPDC donors. To further examine the mechanism of action of compounds with annotated targets, we performed knockdown experiments to understand whether a single known target was responsible for the proliferative effect, confirming results with protein expression and activity assays. Here, we were able to show that the annotated targets of compounds of interest were not responsible for the proliferative effect, which highlights potential differences in cell types and signaling pathways and possible polypharmacology. These studies demonstrate the feasibility of using relevant human primary cells in a phenotypic screen to identify compounds as novel biological tools and starting points for drug discovery projects, and we disclose the first small molecules to proliferate human primary EPDCs.
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Structure-Based Drug Design of Mineralocorticoid Receptor Antagonists to Explore Oxosteroid Receptor Selectivity. ChemMedChem 2016; 12:50-65. [DOI: 10.1002/cmdc.201600529] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 11/22/2016] [Indexed: 01/05/2023]
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SP276HIGH PROTEIN AGGRAVATES, AND MINERALOCORTICOID ANTAGONISM AMELIORATES RENAL INJURY IN THE BTBR OB/OB MOUSE MODEL OF DIABETIC NEPHROPATHY. Nephrol Dial Transplant 2016. [DOI: 10.1093/ndt/gfw164.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Predicting the relative binding affinity of mineralocorticoid receptor antagonists by density functional methods. J Comput Aided Mol Des 2015; 29:1109-22. [PMID: 26572910 DOI: 10.1007/s10822-015-9880-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 11/05/2015] [Indexed: 11/28/2022]
Abstract
In drug discovery, prediction of binding affinity ahead of synthesis to aid compound prioritization is still hampered by the low throughput of the more accurate methods and the lack of general pertinence of one method that fits all systems. Here we show the applicability of a method based on density functional theory using core fragments and a protein model with only the first shell residues surrounding the core, to predict relative binding affinity of a matched series of mineralocorticoid receptor (MR) antagonists. Antagonists of MR are used for treatment of chronic heart failure and hypertension. Marketed MR antagonists, spironolactone and eplerenone, are also believed to be highly efficacious in treatment of chronic kidney disease in diabetes patients, but is contra-indicated due to the increased risk for hyperkalemia. These findings and a significant unmet medical need among patients with chronic kidney disease continues to stimulate efforts in the discovery of new MR antagonist with maintained efficacy but low or no risk for hyperkalemia. Applied on a matched series of MR antagonists the quantum mechanical based method gave an R(2) = 0.76 for the experimental lipophilic ligand efficiency versus relative predicted binding affinity calculated with the M06-2X functional in gas phase and an R(2) = 0.64 for experimental binding affinity versus relative predicted binding affinity calculated with the M06-2X functional including an implicit solvation model. The quantum mechanical approach using core fragments was compared to free energy perturbation calculations using the full sized compound structures.
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Correction to GPR103 Antagonists Demonstrating Anorexigenic Activity in Vivo: Design and Development of Pyrrolo[2,3-c]pyridines That Mimic the C-Terminal Arg-Phe Motif of QRFP26. J Med Chem 2015; 58:4086. [PMID: 25875054 DOI: 10.1021/acs.jmedchem.5b00479] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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GPR103 Antagonists Demonstrating Anorexigenic Activity in Vivo: Design and Development of Pyrrolo[2,3-c]pyridines That Mimic the C-Terminal Arg-Phe Motif of QRFP26. J Med Chem 2014; 57:5935-48. [DOI: 10.1021/jm401951t] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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New Hits as Antagonists of GPR103 Identified by HTS. ACS Med Chem Lett 2014; 5:527-32. [PMID: 24900874 DOI: 10.1021/ml400519h] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 02/22/2014] [Indexed: 12/31/2022] Open
Abstract
Preclinical data indicate that GPR103 receptor and its endogenous neuropeptides QRFP26 and QRFP43 are involved in appetite regulation. A high throughput screening (HTS) for small molecule GPR103 antagonists was performed with the clinical goal to target weight management by modulation of appetite. A high hit rate from the HTS and initial low confirmation with respect to functional versus affinity data challenged us to revise the established screening cascade. To secure high quality data while increasing throughput, the binding assay was optimized on quality to run at single concentration. This strategy enabled evaluation of a larger fraction of chemical clusters and singletons delivering 17 new compound classes for GPR103 antagonism. Representative compounds from three clusters are presented. One of the identified clusters was further investigated, and an initial structure-activity relationship study is reported. The most potent compound identified had a pIC50 of 7.9 with an improved ligand lipophilic efficiency.
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Synthesis, biological evaluation and X-ray crystallographic studies of imidazo[1,2-a]pyridine-based Mycobacterium tuberculosis glutamine synthetase inhibitors. MEDCHEMCOMM 2012. [DOI: 10.1039/c2md00310d] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Synthesis of functionalized cinnamaldehyde derivatives by an oxidative Heck reaction and their use as starting materials for preparation of Mycobacterium tuberculosis 1-deoxy-D-xylulose-5-phosphate reductoisomerase inhibitors. J Org Chem 2011; 76:8986-98. [PMID: 21936546 PMCID: PMC3203620 DOI: 10.1021/jo201715x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
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Cinnamaldehyde derivatives were synthesized in good to excellent yields in one step by a mild and selective, base-free palladium(II)-catalyzed oxidative Heck reaction starting from acrolein and various arylboronic acids. Prepared α,β-unsaturated aldehydes were used for synthesis of novel α-aryl substituted fosmidomycin analogues, which were evaluated for their inhibition of Mycobacterium tuberculosis 1-deoxy-d-xylulose 5-phosphate reductoisomerase. IC50 values between 0.8 and 27.3 μM were measured. The best compound showed activity comparable to that of the most potent previously reported α-aryl substituted fosmidomycin-class inhibitor.
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Abstract
A total of 14 women and seven men with a mean age of 43 years (18 to 68) who sustained a Mason type IV fracture of the elbow, without an additional type II or III coronoid fracture, were evaluated after a mean of 21 years (14 to 46). Primary treatment included closed elbow reduction followed by immobilisation in a plaster in all cases, with an additional excision of the radial head in 11, partial resection in two and suturing of the annular ligament in two. Delayed radial head excision was performed in two patients and an ulnar nerve transposition in one. The uninjured elbows served as controls. Nine patients had no symptoms, 11 reported slight impairment, and one severe impairment of the elbow. Elbow flexion was impaired by a mean of 3° (sd 4) and extension by a mean of 9° (sd 4) (p < 0.01). None experienced chronic elbow instability or recurrent dislocation. There were more degenerative changes in the formerly injured elbows, but none had developed a reduction in joint space. We conclude that most patients with a Mason type IV fracture of the elbow report a good long-term outcome.
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Functionalized 3-amino-imidazo[1,2-a]pyridines: A novel class of drug-like Mycobacterium tuberculosis glutamine synthetase inhibitors. Bioorg Med Chem Lett 2009; 19:4790-3. [DOI: 10.1016/j.bmcl.2009.06.045] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 06/09/2009] [Accepted: 06/11/2009] [Indexed: 11/25/2022]
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Microwave-enhanced alpha-arylation of a protected glycine in water: evaluation of 3-phenylglycine derivatives as inhibitors of the tuberculosis enzyme, glutamine synthetase. Comb Chem High Throughput Screen 2008; 10:783-9. [PMID: 18478959 DOI: 10.2174/138620707783018478] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A microwave-enhanced, palladium-catalyzed protocol for the alpha-arylation of a protected glycine in neat water is described. This reaction proceeds rapidly, under non-inert conditions, to afford a range of phenylglycine derivatives in moderate to good yields. Based on this alpha-arylation, a number of aryl L-methionine-SR-sulfoximine (MSO) analogues were prepared and evaluated for their Mycobacterium tuberculosis glutamine synthetase (TB-GS) inhibitory activity.
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Corrigendum to “Virtual screening and bioassay study of novel inhibitors for dengue virus mRNA cap (nucleoside-2′O)-methyltransferase” [Bioorg. Med. Chem. 15 (2007) 7795–7802]. Bioorg Med Chem 2008. [DOI: 10.1016/j.bmc.2008.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Quantitative structure-activity relationships of pine weevil antifeedants, a multivariate approach. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2007; 55:9365-9372. [PMID: 17927202 DOI: 10.1021/jf070014p] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Antifeedant activity of mainly phenylpropanoic, cinnamic, and benzoic acids esters was tested on the pine weevil, Hylobius abietis (L.). Of 105 compounds screened for activity, 9 phenylpropanoates, 3 cinnamates, and 4 benzoates were found to be highly active antifeedants. To understand the structure-activity relationships of these compounds, a multivariate analysis study was performed. A number of molecular and substituent descriptors were calculated and correlated to results from two-choice feeding tests with H. abietis. Three local models were developed that had good internal predictive ability. External test sets showed moderate predictivity. In general, low polarity, small size, and high lipophilicity were characteristics for compounds having good antifeedant activity.
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Virtual screening and bioassay study of novel inhibitors for dengue virus mRNA cap (nucleoside-2'O)-methyltransferase. Bioorg Med Chem 2007; 15:7795-802. [PMID: 17888664 DOI: 10.1016/j.bmc.2007.08.049] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2007] [Revised: 08/17/2007] [Accepted: 08/24/2007] [Indexed: 10/22/2022]
Abstract
We report high-throughput structure-based virtual screening of putative Flavivirus 2'-O-methyltransferase inhibitors together with results from subsequent bioassay tests of selected compounds. Potential inhibitors for the S-adenosylmethionine binding site were explored using 2D similarity searching, pharmacophore filtering and docking. The inhibitory activities of 15 top-ranking compounds from the docking calculations were tested on a recombinant methyltransferase with the RNA substrate (7Me)GpppAC(5). Local and global docking simulations were combined to estimate the ligand selectivity for the target site. The results of the combined computational and experimental screening identified a novel inhibitor, with a previously unknown scaffold, that has an IC(50) value of 60 microM.
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Links between bacterial production, amino-acid utilization and community composition in productive lakes. ISME JOURNAL 2007; 1:532-44. [PMID: 18043654 DOI: 10.1038/ismej.2007.64] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Influence of distribution and abundance of bacterial taxa on ecosystem function are poorly understood for natural microbial communities. We related 16S rRNA-based terminal restriction fragment length polymorphism to bacterial production and arginine uptake kinetics to test if functional features of bacterioplankton in four lakes could be predicted from community composition. Maximum arginine uptake rate (arginine V(max)) ranged from 10% to 100% of bacterial production. Owing to high growth efficiencies on arginine (63-77%), the bacterial community could potentially saturate its carbon demand using this single organic substrate, for example, during sudden surges of free amino acids. However, due to low in situ concentrations of arginine in these lakes (<0.9 microg l(-1)), actual uptake rates at ambient concentrations rarely exceeded 10% of V(max). Bacterial production and arginine V(max) could be predicted from a subset of bacterial ribotypes, tentatively affiliated with several bacterial divisions (Cyanobacteria, Actinobacteria, Bacteroidetes and Proteobacteria). Multivariate statistical analysis indicates that there were both highly important and less important ribotypes for the prediction of bacterial production and arginine V(max). These populations were either negatively or positively related to the respective functional feature, indicating contrasting ecological roles. Our study provides a statistically robust demonstration that, apart from environmental conditions, patterns in bacterial community composition can also be used to predict lake ecosystem function.
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Increased fragility in patients with fracture of the proximal humerus: a case control study. Bone 2004; 34:1072-7. [PMID: 15193555 DOI: 10.1016/j.bone.2004.01.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2003] [Revised: 12/12/2003] [Accepted: 01/21/2004] [Indexed: 11/25/2022]
Abstract
The aim of this study was to evaluate whether a fracture of the proximal humerus is associated with an increased prevalence of preceding fractures or a risk of subsequent fractures. All patients who were treated at the Malmö General Hospital in 1987 for a fresh fracture of the proximal humerus were identified, representing practically all fractures of the proximal humerus in Malmö city (250,000) that year. Two hundred fifty-three adult patients, 54 men with an average age of 66 (24-90) and 199 women with a mean age of 74 (22-98) years, were included in the study together with 475 age- and gender-matched control persons. In 1999, fracture prevalence of patients and controls were rated by a survey at the Dept. of Radiology. There was a significantly increased prevalence of previous fractures before 1987 in the humerus fracture group with an odds ratio (OR) of 3.5 [95% confidence interval (95% CI), 2.2-5.5] for a spinal fracture, OR 1.8 (95% CI, 1.3-2.6) for a previous fracture to the upper extremity, and OR 1.8 (95% CI, 1.2-2.6) for a preceding fracture of the lower limb. The proximal humerus fracture also predicted a significantly increased risk of a subsequent fracture. The hazard ratio (HR) was 2.5 (95% CI, 1.7-3.7) for a forthcoming spinal fracture, HR 2.8 (95% CI, 2.0-3.7) for a future fracture of the upper extremity, and HR 2.0 (95% CI, 1.2-3.5) for a lower limb fracture. In a subgroup of male patients, an almost five times increased risk of sustaining subsequent extremity fractures was observed. In summary, a fracture of the proximal humerus is associated both with increased prevalence of previous fractures of the spine and extremities and also predicting an increased risk of future fractures.
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Dynamics in maximal settling capacity in an activated sludge treatment plant with highly loaded secondary settlers. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2004; 50:187-194. [PMID: 15553475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Secondary settling dynamics at maximal capacity were investigated at a full scale wastewater treatment plant which utilizes a unique process solution incorporating pre-denitrification with post-nitrification in nitrifying trickling filters. Since nitrogen removal is greater when more secondary effluent is recirculated to the trickling filters, the secondary settlers generally operate at close to their maximal capacity. The settling and flocculation properties of the activated sludge are therefore a major capacity-determining factor for plant operation. Due to the short sludge age, the flocculation properties, with respect to both thickening and clarification, can change quickly. The dynamics in these changes were studied and the factors that determine the maximal settling capacity were assessed. Solids flux curves were constructed from batch settling tests and compared with the actual maximal settling capacities.
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Reducing the total discharge from a large WWTP by separate treatment of primary effluent overflow. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2004; 50:157-162. [PMID: 15553471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
At many large wastewater treatment plants (WWTPs) the increased hydraulic load, caused by combined sewer systems during storm events, results in primary effluent overflow when the capacity of further treatment is exceeded. Due to stringent effluent standards, regulating the total discharge from the WWTPs, the Rya WWTP in Göteborg and the Sjölunda WWTP in Malmö will have to reduce the impact of primary effluent overflow. Separate, high rate, precipitation processes operated only during high flow conditions have been investigated in pilot units at the two WWTPs. Precipitation in existing primary settlers operated at a surface loading of 3.75 m/h removed phosphorus to 0.35 mg/l. The Actiflo process was also shown to remove suspended solids and phosphorus well. BOD was reduced by 50-60%. With such processes the overall effluent concentrations from the plants can be reduced significantly. Key upgrading features are small footprints, short start up time and high efficiency.
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Fewer problems with dry nasal mucous membranes following local use of sesame oil. Rhinology 2000; 38:200-3. [PMID: 11190757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Many people experience problems with a dry nasal mucous membrane, often without wondering why. Their noses itch and burn and dried mucus collects there. These problems are exacerbated during the winter, in air-conditioned environments and after nasal irradiation. Twenty patients experiencing problems with dryness of the nose were selected from outpatient clinics, together with twenty patients who had previously undergone nasal irradiation. During the first five days no treatment was administered. For the following twenty days the patients sprayed sesame oil into each nostril three times a day. For the last five days no treatment was given. When both groups received treatment and sprayed sesame oil (Nozoil) in their noses, the nasal problems decreased significantly. The greatest effect is exerted on dryness. The side effects from using this oil are few in number and mild.
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Abstract
OBJECTIVE The aim of the present study was to analyze the long-term outcome of mid-clavicle fractures in adults and to evaluate the clinical importance of displacement and fracture comminution. DESIGN Two hundred twenty-five mid-clavicular fractures that had been nonsurgically treated at Malmö University Hospital were retrospectively evaluated, both clinically and radiographically, an average of seventeen years after injury. There were seventy-one undisplaced fractures, sixty-nine displaced two-fragment fractures, and eighty-five displaced and comminuted fractures. The average patient age at the time of trauma was thirty-three years (range 15 to 70 years). Patients were interviewed, and careful clinical and radiological examination of their shoulders was performed. Two patients had experienced transient neuritis, and another two underwent operative treatment because of progressive neuropathy. SETTING All 225 consecutive patients were treated primarily at the Malmö University Hospital, which serves the Malmö city population (250,000). PATIENTS/PARTICIPANTS Since the beginning of this century, all radiographs taken at the Malmö University Hospital have been classified and filed for easy retrieval. In this retrospective study, all patients treated between 1970 and 1979 were identified, and those still living were called for follow-up examination. INTERVENTION Of the 225 fractures reviewed, 197 fractures were originally treated with a figure-of-eight splint for an average period of three weeks without any attempt to reduce the displaced fractures; twenty-four patients were allowed immediate free shoulder mobilization. MAIN OUTCOME MEASUREMENTS Clinical rating and healing were the main outcome measurements. RESULTS At follow-up, 185 shoulders were asymptomatic. Thirty-nine shoulders had moderate pain and were rated as fair, and one patient was rated as poor. One hundred twenty-five of the fractures had healed normally, fifty-three were malunited with persistent fracture displacement, and seven were nonunions; nonunion was significantly more prevalent in cases with displaced fractures. Forty malunited fractures and three nonunions were rated as good. CONCLUSIONS This review demonstrates that few patients with fractures of the mid-part of the clavicle require operative treatment.
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Abstract
In a single-blind, randomised series of knee replacements in 116 patients, we used radiostereometric analysis (RSA) to measure micromotion in three types of tibial implant fixation for two years after knee replacement. We compared hydroxyapatite-augmented porous coating, porous coating, and cemented fixation of the same design of tibial component. At one to two years, porous-coated implants migrated at a statistically significantly higher rate than hydroxyapatite-augmented or cemented implants. There was no significant difference between hydroxyapatite-coated and cemented implants. We conclude that hydroxyapatite augmentation may offer a clinically relevant advantage over a simple porous coating for tibial component fixation, but is no better than cemented fixation.
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Hydroxyapatite augmentation of the porous coating improves fixation of tibial components. A randomised RSA study in 116 patients. THE JOURNAL OF BONE AND JOINT SURGERY. BRITISH VOLUME 1998; 80:417-25. [PMID: 9619929 DOI: 10.1302/0301-620x.80b3.7937] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In a single-blind, randomised series of knee replacements in 116 patients, we used radiostereometric analysis (RSA) to measure micromotion in three types of tibial implant fixation for two years after knee replacement. We compared hydroxyapatite-augmented porous coating, porous coating, and cemented fixation of the same design of tibial component. At one to two years, porous-coated implants migrated at a statistically significantly higher rate than hydroxyapatite-augmented or cemented implants. There was no significant difference between hydroxyapatite-coated and cemented implants. We conclude that hydroxyapatite augmentation may offer a clinically relevant advantage over a simple porous coating for tibial component fixation, but is no better than cemented fixation.
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Shortening of clavicle after fracture. Incidence and clinical significance, a 5-year follow-up of 85 patients. ACTA ORTHOPAEDICA SCANDINAVICA 1997; 68:349-51. [PMID: 9310038 DOI: 10.3109/17453679708996175] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We evaluated the incidence and clinical significance of postfracture shortening of the clavicle in 85 patients. There were 71 mid-clavicular fractures and 14 of the lateral end of the clavicle. 46 fractures were primarily undisplaced and 39 displaced. All fractures were nonoperatively treated with sling immobilization. All patients were reexamined 5 years after the fracture. 35 clavicles had healed with at least 5 mm shortening. Clavicles with originally displaced fractures were shorter and radiologically more frequently malunited. Mobility, strength and the functional Constant score were similar in the injured and normal shoulders. Our findings suggest that permanent shortening of the clavicle is common after fracture, but has no clinical significance.
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Shoulder injuries common in alcoholics. An analysis of 413 injuries. ACTA ORTHOPAEDICA SCANDINAVICA 1996; 67:364-6. [PMID: 8792740 DOI: 10.3109/17453679609002332] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We recorded prospectively all adult patients with a fracture of the proximal end of the humerus, clavicle and scapula or a primary shoulder or acromioclavicular dislocation in the city of Malmö in 1987. Altogether there were 413 injures. The hospital records from the Department of Alcohol Diseases were searched for these patients and for 2 age- and gender-matched controls for each patient. 12% of all patients with a shoulder injury were recorded as alcohol abusers. This number was significantly greater than that of the controls. The difference was more obvious in men than in women. In men between 30 and 64 years, almost half of the proximal humerus fractures and shoulder dislocations, one third of mid-clavicular fractures and two thirds of all lateral clavicle fractures were sustained by alcohol abusers. Our findings emphasize the significance of alcohol abuse in the etiology of shoulder injuries, especially in men. Most of the men with a fracture of the lateral clavicle are registered at the Department of Alcohol Diseases, making this injury a marker of alcohol abuse.
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Abstract
In a prospective population-based study of all shoulder injuries seen at Malmö General Hospital during 1987, the incidence and causes of major injuries involving fractures of the clavicle, scapula, or proximal humerus and glenohumeral or acromioclavicular dislocations were investigated in children, adults, and the elderly. Seventy-five shoulder injuries occurred in children. Sixty-five of them were fractures of the clavicle. In this age group no sex-related differences were seen in incidence, and 37 of 73 injuries were related to sports or playing. One hundred eighty-one injuries occurred in adults. Sixty fractures of the proximal humerus, 67 fractures of the clavicle, and 31 primary glenohumeral dislocations were seen. The injuries in this group were significantly more frequent in men, with most of them caused by traffic and sport injuries. Two hundred forty-eight injuries occurred in elderly people. Two hundred one were fractures of the proximal humerus. The incidence was significantly higher in women; 147 of 247 injuries were caused by an indoor fall. The variations among age groups are probably attributable to age-related differences in activity, mobility, and fragility.
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The incidence of fractures of the clavicle. Clin Orthop Relat Res 1994:127-32. [PMID: 8131324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The age- and gender-specific incidences were calculated in 2035 cases of fracture of the clavicle. The fractures were classified in three groups according to the Allman system. Each group was further divided into undisplaced and displaced fracture subgroups, with an extra subgroup of comminuted midclavicular fractures in Group I. Seventy-six percent of the fractures were classified as Allman Group I. The median age in this group was 13 years. There were significant differences in age- and gender-specific incidence between the undisplaced, displaced, and comminuted fracture subgroups. Twenty-one percent were classified as Allman Group II. The median age of the patients was 47 years, and there was no difference in age between the undisplaced and displaced fracture subgroups. Three percent were classified as Allman Group III, and the median age of the patients in this group was 59 years. All three groups were characterized by a significant preponderance of men, and there was a significant increase in the incidence of clavicular fracture, both overall and sports-related, between 1952 and 1987.
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The natural course of lateral clavicle fracture. 15 (11-21) year follow-up of 110 cases. ACTA ORTHOPAEDICA SCANDINAVICA 1993; 64:87-91. [PMID: 8451958 DOI: 10.3109/17453679308994539] [Citation(s) in RCA: 174] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
110 patients with non-operated on fracture of the lateral end of the clavicle were reviewed on an average 15 years after the injury. There were 73 undislocated Neer Type I fractures, 23 dislocated Type II fractures and 14 intraarticular Type III fractures. The patients' age at trauma was 36 (2-71) years. At follow-up 95 shoulders were asymptomatic. 15 shoulders had moderate pain and dysfunction and were rated fair; no patient had severe, residual shoulder disability. There were 10 nonunions, 8 of these asymptomatic. We conclude that fracture of the lateral end of the clavicle does not require operation.
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Fracture of the body, neck, or spine of the scapula. A long-term follow-up study. Clin Orthop Relat Res 1992:139-44. [PMID: 1395237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Fractures of the scapula are often considered benign lesions with a favorable outcome. The aim of the current study was to analyze the long-term results after fracture of the muscle-covered parts of the scapula: its body, neck, and spine. Sixty-eight patients were available for clinical examination 14 years after they had sustained a fracture of the scapula. The fractures had been treated with immobilization and early active motion. The follow-up rating was based on patient satisfaction and shoulder motion. Fifty-one patients were rated good, 15 were rated fair, and two were rated poor. Forty-eight shoulders were roentgenographically reexamined. Fourteen had a moderate and six had a pronounced deformity of the scapula. Scapula deformity was associated with pain in eight of the shoulders. The results of the current study suggest that the long-term course after fracture of the scapula is not uniformly favorable. Fifty percent of the patients with residual scapula deformity have shoulder symptoms. In most cases, however, the shoulder disablement is slight or moderate.
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