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- Ayeni, O. R., et al.
(författare)
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Clinical and Radiographic Criteria Define "Acceptable" Surgical Correction of Hip Femoroacetabular Impingement Syndrome as Well as Postoperative Complications: An International Modified Delphi Study
- 2023
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Ingår i: Arthroscopy-the Journal of Arthroscopic and Related Surgery. - : Elsevier BV. - 0749-8063. ; 39:5, s. 1198-1210
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: To develop recommendations for clinical and radiographic criteria to help define the "acceptable" surgical correction of femoroacetabular impingement syndrome (FAIS) and identify/define complications postoperatively. Methods: A 3-phase modified Delphi study was conducted involving a case-based survey; a Likert/multiple choice-based survey concerning radiographic and physical examination characteristics to help define FAIS correction, as well as the prevalence and definition of potential postoperative complications; and 2 consensus meetings. Results: Of the 75 experts invited, 54 completed the Phase I survey, 50 completed the Phase II survey (72% and 67% response rate), and 50 participated in the Phase III consensus meetings. For both typical and atypical (complex) cases, there was consensus that fluoroscopy with multiple views and dynamic hip assessment should be used intraoperatively (96% and 100%, respectively). For typical FAIS cases, the Expert Panel agreed that Dunn lateral and anteroposterior radiographs were the most important radiographs to evaluate the hip postoperatively (88%, consensus). When asked about evaluating the correction of cam impingement postoperatively, 87% voted that they use subjective evaluation of the "sphericity" of the femoral head. In the case of focal and global pincer-type FAIS, there was consensus that the reduction or elimination of the crossover sign (84%) and lateral center-edge angle (91%) were important to inform the extent of the FAIS correction. There was consensus for recommending further investigation at 6 months postoperatively if hip pain had increased/plateaued (92% agreed); that additional investigation and treatment should occur between 6 and 12 months (90% agreed); and that a reoperation may be recommended at 12 months or later following this investigation period (89% agreed). Conclusions: This consensus project identified the importance of using fluoroscopy and dynamic hip assessment intraoperatively; Dunn lateral and anteroposterior view radiographs postoperatively; evaluating the "sphericity" of the femoral head for cam-type correction and the use of dynamic hip assessment; reducing/eliminating the crossover sign for focal pincertype FAIS; evaluating the lateral center-edge angle for global pincer-type FAIS; and avoiding overcorrection of pincer-type FAIS. In cases in which postoperative hip pain increased/plateaued, further investigation and treatment is warranted between 6 and 12 months, and a reoperation may be recommended at a minimum of 12 months depending on the cause of the hip pain. Clinical Relevance: Hip arthroscopy surgeons have yet to reach a firm agreement on what constitutes an "acceptable" or "good" surgery radiographically and how they can achieve desired clinical outcomes. Although this was a comprehensive effort, more study is needed to determine therapeutic thresholds that can be universally applied.
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2. |
- Mahajan, Anubha, et al.
(författare)
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Fine-mapping type 2 diabetes loci to single-variant resolution using high-density imputation and islet-specific epigenome maps
- 2018
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Ingår i: Nature Genetics. - : NATURE PUBLISHING GROUP. - 1061-4036 .- 1546-1718. ; 50:11, s. 1505-
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Tidskriftsartikel (refereegranskat)abstract
- We expanded GWAS discovery for type 2 diabetes (T2D) by combining data from 898,130 European-descent individuals (9% cases), after imputation to high-density reference panels. With these data, we (i) extend the inventory of T2D-risk variants (243 loci,135 newly implicated in T2D predisposition, comprising 403 distinct association signals); (ii) enrich discovery of lower-frequency risk alleles (80 index variants with minor allele frequency <5%,14 with estimated allelic odds ratio >2); (iii) substantially improve fine-mapping of causal variants (at 51 signals, one variant accounted for >80% posterior probability of association (PPA)); (iv) extend fine-mapping through integration of tissue-specific epigenomic information (islet regulatory annotations extend the number of variants with PPA >80% to 73); (v) highlight validated therapeutic targets (18 genes with associations attributable to coding variants); and (vi) demonstrate enhanced potential for clinical translation (genome-wide chip heritability explains 18% of T2D risk; individuals in the extremes of a T2D polygenic risk score differ more than ninefold in prevalence).
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3. |
- Alonso, Lorena, et al.
(författare)
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TIGER : The gene expression regulatory variation landscape of human pancreatic islets
- 2021
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Ingår i: Cell Reports. - : Elsevier BV. - 2211-1247. ; 37:2
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Tidskriftsartikel (refereegranskat)abstract
- Genome-wide association studies (GWASs) identified hundreds of signals associated with type 2 diabetes (T2D). To gain insight into their underlying molecular mechanisms, we have created the translational human pancreatic islet genotype tissue-expression resource (TIGER), aggregating >500 human islet genomic datasets from five cohorts in the Horizon 2020 consortium T2DSystems. We impute genotypes using four reference panels and meta-analyze cohorts to improve the coverage of expression quantitative trait loci (eQTL) and develop a method to combine allele-specific expression across samples (cASE). We identify >1 million islet eQTLs, 53 of which colocalize with T2D signals. Among them, a low-frequency allele that reduces T2D risk by half increases CCND2 expression. We identify eight cASE colocalizations, among which we found a T2D-associated SLC30A8 variant. We make all data available through the TIGER portal (http://tiger.bsc.es), which represents a comprehensive human islet genomic data resource to elucidate how genetic variation affects islet function and translates into therapeutic insight and precision medicine for T2D.
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5. |
- Hastoy, B., et al.
(författare)
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Electrophysiological properties of human beta-cell lines EndoC-beta H1 and -beta H2 conform with human beta-cells
- 2018
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Limited access to human islets has prompted the development of human beta cell models. The human beta cell lines EndoC-beta H1 and EndoC-beta H2 are increasingly used by the research community. However, little is known of their electrophysiological and secretory properties. Here, we monitored parameters that constitute the glucose-triggering pathway of insulin release. Both cell lines respond to glucose (6 and 20 mM) with 2- to 3-fold stimulation of insulin secretion which correlated with an elevation of [Ca2+](i), membrane depolarisation and increased action potential firing. Similar to human primary beta cells, K-ATP channel activity is low at 1mM glucose and is further reduced upon increasing glucose concentration; an effect that was mimicked by the K-ATP channel blocker tolbutamide. The upstroke of the action potentials reflects the activation of Ca2+ channels with some small contribution of TTX-sensitive Na+ channels. The repolarisation involves activation of voltage-gated Kv2.2 channels and large-conductance Ca2+-activated K+ channels. Exocytosis presented a similar kinetics to human primary beta cells. The ultrastructure of these cells shows insulin vesicles composed of an electrondense core surrounded by a thin clear halo. We conclude that the EndoC-beta H1 and -beta H2 cells share many features of primary human beta-cells and thus represent a useful experimental model.
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6. |
- Herrera-Marschitz, M, et al.
(författare)
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On the origin of extracellular glutamate levels monitored in the basal ganglia of the rat by in vivo microdialysis
- 1996
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Ingår i: Journal of Neurochemistry. - : Wiley. - 0022-3042 .- 1471-4159. ; 66:4, s. 1726-1735
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Tidskriftsartikel (refereegranskat)abstract
- Several putative neurotransmitters and metabolites were monitored simultaneously in the extracellular space of neostriatum, substantia nigra, and cortex and in subcutaneous tissue of the rat by in vivo microdialysis. Glutamate (Glu) and aspartate (Asp) were at submicromolar and gamma-aminobutyric acid (GABA) was at nanomolar concentrations in all brain regions. The highest concentration of dopamine (DA) was in the neostriatum. Dynorphin B (Dyn B) was in the picomolar range in all brain regions. Although no GABA, DA, or Dyn B could be detected in subcutaneous tissue, Glu and Asp levels were 5 and approximately 5 and approximately 0.4 microM, respectively. Lactate and pyruvate concentrations were approximately 200 and approximately 10 microM in all regions. The following criteria were applied to ascertain the neuronal origin of substances quantified by microdialysis: sensitivity to (a) K+ depolarization, (b) Na+ channel blockade, (c) removal of extracellular Ca2+, and (d) depletion of presynaptic vesicles by local administration of alpha-latrotoxin. DA, Dyn B, and GABA largely satisfied all these criteria. In contrast, Glu and Asp levels were not greatly affected by K+ depolarization and were increased by perfusing with tetrodotoxin or with Ca2+-free medium, arguing against a neuronal origin. However, Glu and Asp, as well as DA and GABA, levels were decreased under both basal and K+-depolarizing conditions by alpha-latrotoxin. Because the effect of K+ depolarization on Glu and Asp could be masked by reuptake into nerve terminals and glial cells, the reuptake blocker dihydrokainic acid (DHKA) or L-trans-pyrrolidine-2,4-dicarboxylic acid (PDC) was included in the microdialysis perfusion medium. The effect of K+ depolarization on Glu and Asp levels was increased by DHKA, but GABA levels were also affected. In contrast, PDC increased only Glu levels. It is concluded that there is pool of releasable Glu and Asp in the rat brain. However, extracellular levels of amino acids monitored by in vivo microdialysis reflect the balance between neuronal release and reuptake into surrounding nerve terminals and glial elements.
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7. |
- Kelley, Liam P., et al.
(författare)
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Dimerization of small integral membrane protein 1 promotes cell surface presentation of the Vel blood group epitope
- 2020
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Ingår i: FEBS Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 594:8, s. 1261-1270
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Tidskriftsartikel (refereegranskat)abstract
- The Vel blood group antigen is carried on the short extracellular segment of the 78-amino-acid-long, type II transmembrane protein SMIM1 of unknown function. Here, using biochemical analysis and flow cytometry of cells expressing wild-type and mutant alleles of SMIM1, we demonstrate that dimerization of SMIM1 promotes cell surface display of the Vel epitope. We show that SMIM1 dimerization is mediated both by an extracellular Cys77-dependent, homomeric disulfide linkage and via a GxxxG helix–helix interaction motif in the transmembrane domain. These results provide important context for the observed variability in reactivity patterns of clinically important anti-Vel identified in patient sera.
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9. |
- You, Z-B, et al.
(författare)
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Modulation of neurotransmitter release by cholecystokinin in neostriatum and substantia nigra of the rat : regional and receptor specificity
- 1996
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Ingår i: Neuroscience. - : Elsevier BV. - 0306-4522 .- 1873-7544. ; 74:3, s. 793-804
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Tidskriftsartikel (refereegranskat)abstract
- The effect of cholecystokinin peptides on the release of dynorphin B, aspartate, glutamate, dopamine and GABA in the neostriatum and substantia nigra of the rat was investigated using in vivo microdialysis. Sulphated cholecystokinin-8S in the dialysis perfusate (1-100 microM) induced a concentration-dependent increase in extracellular dynorphin B and aspartate levels, both in the neostriatum and substantia nigra. Striatal dopamine levels were only increased by 100 microM of cholecystokinin-8S, while in the substantia nigra they were increased by 10-100 microM of cholecystokinin-8S. Extracellular GABA and glutamate levels were increased following 100 microM of cholecystokinin-8S only. Striatal cholecystokinin-8S administration also produced a significant increase in nigral dynorphin B levels. Local cholecystokinin-4 (100 microM) produced a moderate, but significant, increase of extracellular dynorphin B and aspartate levels in the neostriatum and substantia nigra. No effect was observed on the other neurotransmitters investigated. A 6-hydroxydopamine lesion of the nigrostriatal dopamine pathway did not affect the increases in dynorphin B and aspartate levels produced by local administration of cholecystokinin-8S. Basal extracellular GABA levels were increased significantly in both the neostriatum and substantia nigra ipsilateral to the lesion. Nigral glutamate and aspartate levels were also increased in the lesioned substantia nigra, but in the lesioned neostriatum aspartate levels were decreased. The cholecystokinin-B antagonist L-365,260 (20 mg/kg, s.c.), but not the cholecystokinin-A antagonist L-364,718 (devazepide; 20 mg/kg, s.c.), significantly inhibited the effect of cholecystokinin-8S on striatal dynorphin B and aspartate levels. In the substantia nigra, however, the effect of cholecystokinin-8S on dynorphin B and aspartate levels was inhibited to a similar extent by both L-365,260 and L-364,718. Pretreatment with L-364,718, but not with L-365.260, prevented the increase in nigral dopamine levels produced by nigral cholecystokinin-8S administration. Taken together, these results suggest that cholecystokinin-8S modulates dynorphin B and aspartate release in the neostriatum and substantia nigra of the rat via different receptor mechanisms. In the neostriatum, the effect of cholecystokinin-8S on dynorphin B and aspartate release is mediated via the cholecystokinin-B receptor subtype, while in the substantia nigra, cholecystokinin-8S modulates dynorphin B and aspartate release via both cholecystokinin-A and cholecystokinin-B receptor subtypes. Cholecystokinin-8S modulates dopamine release mainly in the substantia nigra, via the cholecystokinin-A receptor subtype.
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10. |
- Cappendijk, Susanne L T, et al.
(författare)
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A heroin-, but not a cocaine expecting, self-administration state preferentially alters brain endogenous peptides
- 1999
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Ingår i: European Journal of Pharmacology. - 0014-2999 .- 1879-0712. ; 365:2-3, s. 175-182
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of the current study was to assess neuropeptidergic alterations during a phase of the drug addiction cycle associated with drug craving as compared to a time period when the drug had been recently self-administered. Male Wistar rats were allowed to self-administer cocaine, heroin or saline for 6 h for 5 consecutive days. Immediately following the last self-administration session ('acute drug on board' state), and just before the next scheduled session ('drug expecting' state), the animals were decapitated and the levels of dynorphin A and B, [Met5]- and [Leu5]-enkephalin and substance P were measured in different brain areas. During the 'acute drug on board' state, peptide levels in animals that self-administered heroin or cocaine were not significantly changed. In contrast, during the 'drug expecting' state, heroin-treated animals had increased levels of dynorphin A, dynorphin B and [Met5]-enkephalin in the caudal striatum as compared to the cocaine- and saline-treated animals, and the level of [Leu5]-enkephalin was increased as compared to the cocaine-treated group. In the septum, an increase of [Met5]-enkephalin and substance P was observed in the animals expecting heroin as compared to the saline- and/or cocaine-treated animals. In the caudal striatum, substance P levels were elevated in the heroin- and cocaine-expecting animals. In conclusion, heroin, as compared to cocaine, appears to have a more pronounced effect on dynorphin, enkephalin and substance P levels in the caudal striatum and septum, especially during periods when self-administration of the drug is expected.
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