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In a typical G protein coupled receptor drug discovery campaign, an in vitro primary functional screening assay is often established in a recombinant system overexpressing the target of interest, which offers advantages with respect to overall throughput and robustness of compound testing. Subsequently, compounds are then progressed into more physiologically relevant but lower throughput ex vivo primary cell assays and finally in vivo studies. Here we describe a dynamic mass redistribution (DMR) assay that has been developed in a format suitable to support medium throughput drug screening in primary human neutrophils. Neutrophils are known to express both CXC chemokine receptor (CXCR) 1 and CXCR2 that are thought to play significant roles in various inflammatory disorders and cancer. Using multiple relevant chemokine ligands and a range of selective and nonselective small and large molecule antagonists that block CXCR1 and CXCR2 responses, we demonstrate distinct pharmacological profiles in neutrophil DMR from those observed in recombinant assays but predictive of activity in neutrophil chemotaxis and CD11b upregulation, a validated target engagement marker previously used in clinical studies of CXCR2 antagonists. The primary human neutrophil DMR cell system is highly reproducible, robust, and less prone to donor variability observed in CD11b and chemotaxis assays and thus provides a unique, more physiologically relevant, and higher throughput assay to support drug discovery and translation to early clinical trials. SIGNIFICANCE STATEMENT: Neutrophil dynamic mass redistribution assays provide a higher throughput screening assay to profile compounds in primary cells earlier in the screening cascade enabling a higher level of confidence in progressing the development of compounds toward the clinic. This is particularly important for chemokine receptors where redundancy contributes to a lack of correlation between recombinant screening assays and primary cells, with the coexpression of related receptors confounding results.
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Interleucina-8 , Neutrófilos , Humanos , Interleucina-8/metabolismo , Receptores de Quimiocina , Quimiocinas/metabolismo , Quimiotaxis de Leucocito/fisiología , Receptores de Interleucina-8B/metabolismo , Receptores de Interleucina-8A/metabolismoRESUMEN
OBJECTIVE: Somatostatin receptor ligands have come to play a pivotal role in the treatment of both ACTH- and GH-secreting pituitary adenomas. Clinical efficacy averages 30-50%, thus a considerable number of patients with Cushing's disease or acromegaly remain unresponsive to this therapeutic approach. HTL0030310 is a new somatostatin receptor ligand selective for subtype 5 over subtype 2, thus with a different receptor profile compared to clinical somatostatin receptor ligands. DESIGN: Assessment of the effect of HTL0030310 on hormone secretion in human ACTH- and GH-secreting pituitary adenomas in vitro. METHODS: Primary cultures from 3 ACTH-secreting and 5 GH-secreting pituitary adenomas were treated with 1, 10 and 100 nM HTL0030310 alone or with 10 nM CRH or GHRH, respectively. Parallel incubations with 10 nM pasireotide were also carried out. ACTH and GH secretion were assessed after 4 and 24 hour incubation; SSTR2, SSTR3, SSTR5, GH and POMC expression were evaluated after 24 hours. RESULTS: HTL0030310 reduced unchallenged ACTH and POMC levels up to 50% in 2 ACTH-secreting adenomas and blunted CRH-stimulated ACTH/POMC by 20-70% in all 3 specimens. A reduction in spontaneous GH secretion was observed in 4 GH-secreting adenomas and in 2 specimens during GHRH co-incubation. SSTRs expression was detected in all specimens. CONCLUSIONS: This first study on a novel somatostatin receptor 5-preferring ligand indicates that HTL0030310 can inhibit hormonal secretion in human ACTH- and GH-secreting pituitary adenomas. These findings suggest a potential new avenue for somatostatin ligands in the treatment of Cushing's disease and acromegaly.
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Acromegalia , Adenoma , Adenoma Hipofisario Secretor de Hormona del Crecimiento , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT) , Neoplasias Hipofisarias , Humanos , Receptores de Somatostatina/metabolismo , Neoplasias Hipofisarias/tratamiento farmacológico , Adenoma Hipofisario Secretor de Hormona del Crecimiento/tratamiento farmacológico , Acromegalia/tratamiento farmacológico , Proopiomelanocortina/metabolismo , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/tratamiento farmacológico , Ligandos , Adenoma/metabolismo , Hormona Adrenocorticotrópica/metabolismoRESUMEN
HTL0041178 (1), a potent GPR52 agonist with a promising pharmacokinetic profile and exhibiting oral activity in preclinical models, has been identified. This molecule was the outcome of a judicious molecular property-based optimization approach, focusing on balancing potency against metabolic stability, solubility, permeability, and P-gp efflux.
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The low affinity metabotropic glutamate receptor mGluR7 has been implicated in numerous CNS disorders; however, a paucity of potent and selective activators has hampered full delineation of the functional role and therapeutic potential of this receptor. In this work, we present the identification, optimization, and characterization of highly potent, novel mGluR7 agonists. Of particular interest is the chromane CVN636, a potent (EC50 7 nM) allosteric agonist which demonstrates exquisite selectivity for mGluR7 compared to not only other mGluRs, but also a broad range of targets. CVN636 demonstrated CNS penetrance and efficacy in an in vivo rodent model of alcohol use disorder. CVN636 thus has potential to progress as a drug candidate in CNS disorders involving mGluR7 and glutamatergic dysfunction.
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GPR84 is a poorly characterized, nominally orphan, proinflammatory G protein-coupled receptor that can be activated by medium chain length fatty acids. It is attracting considerable interest as a potential therapeutic target for antagonist ligands in both inflammatory bowel diseases and idiopathic pulmonary fibrosis. Successful screening of more than 300â¯000 compounds from a small molecule library followed by detailed analysis of some 50 drug-like hits identified 3-((5,6-bis(4-methoxyphenyl)-1,2,4-triazin-3-yl)methyl)-1H-indole as a high affinity and highly selective competitive antagonist of human GPR84. Tritiation of a di-iodinated form of the core structure produced [3H]3-((5,6-diphenyl-1,2,4-triazin-3-yl)methyl)-1H-indole, which allowed effective measurement of receptor levels in both transfected cell lines and lipopolysaccharide-treated THP-1 monocyte/macrophage cells. Although this compound series lacks significant affinity at mouse GPR84, homology modeling and molecular dynamics simulations provided a potential rationale for this difference, and alteration of two residues in mouse GPR84 to the equivalent amino acids in the human orthologue, predicted to open the antagonist binding pocket, validated this model. Sequence alignment of other species orthologues further predicted binding of the compounds as high affinity antagonists at macaque, pig, and dog GPR84 but not at the rat orthologue, and pharmacological experiments confirmed these predictions. These studies provide a new class of GPR84 antagonists that display species selectivity defined via receptor modeling and mutagenesis.
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BACKGROUND: Glioma is a family of primary brain malignancies with limited treatment options and in need of novel therapies. We previously demonstrated that the adhesion G protein-coupled receptor GPR133 (ADGRD1) is necessary for tumor growth in adult glioblastoma, the most advanced malignancy within the glioma family. However, the expression pattern of GPR133 in other types of adult glioma is unknown. METHODS: We used immunohistochemistry in tumor specimens and non-neoplastic cadaveric brain tissue to profile GPR133 expression in adult gliomas. RESULTS: We show that GPR133 expression increases as a function of WHO grade and peaks in glioblastoma, where all tumors ubiquitously express it. Importantly, GPR133 is expressed within the tumor bulk, as well as in the brain-infiltrating tumor margin. Furthermore, GPR133 is expressed in both isocitrate dehydrogenase (IDH) wild-type and mutant gliomas, albeit at higher levels in IDH wild-type tumors. CONCLUSION: The fact that GPR133 is absent from non-neoplastic brain tissue but de novo expressed in glioma suggests that it may be exploited therapeutically.
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INTRODUCTION: Pericardial involvement of sarcoidosis is a rare cause for acute heart failure, and usually occurs as a result of the development of a pericardial effusion leading to cardiac tamponade. Even rarer still, is the manifestation of constrictive pericarditis. We report a case of sarcoidosis with lung, pleural, and pericardial involvement with effusive-constrictive pericarditis leading to cardiac tamponade. CASE PRESENTATION: A 34-year-old Caucasian man presented for evaluation of a history of worsening exertional dyspnea, edema, and weight loss. A high-resolution chest computed tomography showed diffuse pulmonary nodules with upper lobe predominance and in a perilymphatic distribution; large right pleural effusion; and large pericardial effusion with pericardial thickening. A transthoracic echocardiogram demonstrated early tamponade physiology for which a pericardial drain was placed. After removal of the drain he developed cardiogenic shock from cardiac tamponade attributed to the reaccumulation of a pericardial effusion and urgent pericardial window was performed. Serial echocardiography was concerning for organization and localization of the pericardial fluid. Cardiac magnetic resonance imaging demonstrated a significant reduction in pericardial slippage between the parietal and visceral layers around the heart collectively suggestive of constrictive pericarditis. Confirmation of effusive-constrictive pericarditis was noted on right heart catheterization. He then underwent pericardiectomy, which on histopathologic evaluation demonstrated non-necrotizing granulomas, thus confirming pericardial involvement of sarcoidosis. CONCLUSIONS: We report a case demonstrating unique manifestations of sarcoidosis; effusive-constrictive pericarditis presenting with acute congestive heart failure.
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Derrame Pericárdico/etiología , Pericarditis Constrictiva/etiología , Sarcoidosis/complicaciones , Adulto , Cateterismo Cardíaco , Taponamiento Cardíaco/diagnóstico por imagen , Taponamiento Cardíaco/etiología , Ecocardiografía , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/etiología , Humanos , Imagen por Resonancia Magnética , Masculino , Derrame Pericárdico/diagnóstico por imagen , Pericarditis Constrictiva/diagnóstico por imagenRESUMEN
BACKGROUND: There is a paucity of studies reporting on women's injuries in rugby union. OBJECTIVE: The aim of this systematic review was to describe the injury epidemiology for women's rugby-15s and rugby-7s match and training environments. METHODS: Systematic searches of PubMed, SPORTDiscus, Web of Science Core Collection, Scopus, CINAHL(EBSCO) and ScienceDirect databases using keywords. RESULTS: Ten articles addressing the incidence of injury in women's rugby union players were retrieved and included. The pooled incidence of injuries in women's rugby-15s was 19.6 (95% CI 17.7-21.7) per 1000 match-hours (h). Injuries in women's rugby-15s varied from 3.6 (95% CI 2.5-5.3) per 1000 playing-h (including training and games) to 37.5 (95% CI 26.5-48.5) per 1000 match-h. Women's rugby-7s had a pooled injury incidence of 62.5 (95% CI 54.7-70.4) per 1000 player-h and the injury incidence varied from 46.3 (95% CI 38.7-55.4) per 1000 match-h to 95.4 (95% CI 79.9-113.9) per 1000 match-h. The tackle was the most commonly reported injury cause with the ball carrier recording more injuries at the collegiate [5.5 (95% CI 4.5-6.8) vs. 3.5 (95% CI 2.7-4.6) per 1000 player-game-h; χ2(1) = 6.7; p = 0.0095], and Women's Rugby World Cup (WRWC) [2006: 14.5 (95% CI 8.9-23.7) vs. 10.9 (95% CI 6.2-19.2) per 1000 match-h; χ2(1) = 0.6; p = 0.4497; 2010: 11.8 (95% CI 6.9-20.4) vs. 1.8 (95% CI 0.5-7.3) per 1000 match-h; χ2(1) = 8.1; p = 0.0045] levels of participation. Concussions and sprains/strains were the most commonly reported injuries at the collegiate level of participation. DISCUSSION: Women's rugby-7s had a higher un-pooled injury incidence than women's rugby-15s players based on rugby-specific surveys and hospitalisation data. The incidence of injury in women's rugby-15s and rugby-7s was lower than men's professional rugby-15s and rugby-7s competitions but similar to male youth rugby-15s players. Differences in reporting methodologies limited comparison of results. CONCLUSION: Women's rugby-7s resulted in a higher injury incidence than women's rugby-15s. The head/face was the most commonly reported injury site. The tackle was the most common cause of injury in both rugby-7s and rugby-15s at all levels. Future studies are warranted on injuries in women's rugby-15s and rugby-7s. PROSPERO REGISTRATION NUMBER: CRD42018109054 (last updated on 17 January 2019).
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Traumatismos en Atletas/epidemiología , Fútbol Americano/lesiones , Conmoción Encefálica/epidemiología , Femenino , Fútbol Americano/clasificación , Humanos , Incidencia , Esguinces y Distensiones/epidemiologíaRESUMEN
Many members of the G protein-coupled receptor family, including examples with clear therapeutic potential, remain poorly characterised. This often reflects limited availability of suitable tool ligands with which to interrogate receptor function. In the case of GPR84, currently a target for the treatment of idiopathic pulmonary fibrosis, recent times have seen the description of novel orthosteric and allosteric agonists. Using 2-(hexylthiol)pyrimidine-4,6 diol (2-HTP) and di(5,7-difluoro-1H-indole-3-yl)methane (PSB-16671) as exemplars of each class, in cell lines transfected to express either human or mouse GPR84, both ligands acted as effective on-target activators and with high co-operativity in their interactions. This was also the case in lipopolysaccharide-activated model human and mouse immune cell lines. However in mouse bone-marrow-derived neutrophils, where expression of GPR84 is particularly high, the capacity of PSB-16671 but not of 2-HTP to promote G protein activation was predominantly off-target because it was not blocked by an antagonist of GPR84 and was preserved in neutrophils isolated from GPR84 deficient mice. These results illustrate the challenges of attempting to study and define functions of poorly characterised receptors using ligands that have been developed via medicinal chemistry programmes, but where assessed activity has been limited largely to the initially identified target.
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Receptores Acoplados a Proteínas G/química , Sitio Alostérico , Animales , Sitios de Unión , Células de la Médula Ósea/metabolismo , Proteínas de Unión al GTP/metabolismo , Células HEK293 , Humanos , Fibrosis Pulmonar Idiopática/metabolismo , Ligandos , Lipopolisacáridos/metabolismo , Ratones , Ratones Noqueados , Neutrófilos/metabolismo , Células RAW 264.7 , Receptores Acoplados a Proteínas G/agonistas , Células THP-1RESUMEN
The Lysophosphatidic Acid 1 Receptor (LPA1 receptor) has been linked to the initiation and progression of a variety of poorly treated fibrotic conditions. Several compounds that have been described as LPA1 receptor antagonists have progressed into clinical trials: 1-(4-{4-[3-methyl-4-({[(1R)-1-phenylethoxy]carbonyl}amino)-1,2-oxazol-5-yl]phenyl}phenyl)cyclopropane-1-carboxylic acid (BMS-986202) and 2-{4-methoxy-3-[2-(3-methylphenyl)ethoxy]benzamido}-2,3-dihydro-1H-indene-2-carboxylic acid (SAR-100842). We considered that as LPA1 receptor function is involved in many normal physiological processes, inhibition of specific signalling pathways associated with fibrosis may be therapeutically advantageous. We compared the binding and functional effects of a novel compound; 4-({(Cyclopropylmethyl)[4-(2-fluorophenoxy)benzoyl]amino}methyl}benzoic acid (TAK-615) with BMS-986202 and SAR-100842. Back-scattering interferometry (BSI) was used to show that the apparent affinity of TAK-615 was enhanced in the presence of LPA. The binding signal for BMS-986202 was not detected in the presence of LPA suggesting competition but interestingly the apparent affinity of SAR-100842 was also enhanced in the presence of LPA. Only BMS-986202 was able to fully inhibit the response to LPA in calcium mobilisation, ß-arrestin, cAMP, GTPγS and RhoA functional assays. TAK-615 and SAR-100842 showed different inhibitory profiles in the same functional assays. Further binding studies indicated that TAK-615 is not competitive with either SAR-100842 or BMS-986202, suggesting a different site of binding. The results generated with this set of experiments demonstrate that TAK-615 acts as a negative allosteric modulator (NAM) of the LPA1 receptor. Surprisingly we find that SAR-100842 also behaves like a NAM. BMS-986202 on the other hand behaves like an orthosteric antagonist.
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Benzamidas/farmacología , Benzoatos/farmacología , Ciclopropanos/farmacología , Indenos/farmacología , Oxazoles/farmacología , Receptores del Ácido Lisofosfatídico/metabolismo , Regulación Alostérica , Animales , Benzamidas/química , Benzoatos/química , Calcio/metabolismo , Línea Celular Tumoral , AMP Cíclico/metabolismo , Ciclopropanos/química , Indenos/química , Oxazoles/química , Ratas , Receptores del Ácido Lisofosfatídico/antagonistas & inhibidoresRESUMEN
Disruption of the insulin-PI3K-Akt signalling pathway in kidney podocytes causes endoplasmic reticulum (ER) stress, leading to podocyte apoptosis and proteinuria in diabetic nephropathy. We hypothesised that by improving insulin sensitivity we could protect podocytes from ER stress. Here we use established activating transcription factor 6 (ATF6)- and ER stress element (ERSE)-luciferase assays alongside a novel high throughput imaging-based C/EBP homologous protein (CHOP) assay to examine three models of improved insulin sensitivity. We find that by improving insulin sensitivity at the level of the insulin receptor (IR), either by IR over-expression or by knocking down the negative regulator of IR activity, protein tyrosine-phosphatase 1B (PTP1B), podocytes are protected from ER stress caused by fatty acids or diabetic media containing high glucose, high insulin and inflammatory cytokines TNFα and IL-6. However, contrary to this, knockdown of the negative regulator of PI3K-Akt signalling, phosphatase and tensin homolog deleted from chromosome 10 (PTEN), sensitizes podocytes to ER stress and apoptosis, despite increasing Akt phosphorylation. This indicates that protection from ER stress is conferred through not just the PI3K-Akt pathway, and indeed we find that inhibiting the MEK/ERK signalling pathway rescues PTEN knockdown podocytes from ER stress.
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Estrés del Retículo Endoplásmico , Fosfatidilinositol 3-Quinasas/metabolismo , Podocitos/fisiología , Receptor de Insulina/metabolismo , Transducción de Señal , Animales , Apoptosis , Células Cultivadas , Insulina/metabolismo , Ratones , Fosfohidrolasa PTEN/metabolismo , Fosforilación , Podocitos/citología , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismoRESUMEN
The yeast vacuole plays key roles in cellular stress responses. Here, we show that deletion of lvs1, the fission yeast homolog of the Chediak-Higashi Syndrome CHS1/LYST gene, increases vacuolar size, similar to deletion of the Rab4 homolog ypt4. Overexpression of lvs1-YFP rescued vacuolar size in ypt4Δ cells, but ypt4-YFP did not rescue lvs1Δ, suggesting that lvs1 may act downstream of ypt4. Vacuoles were capable of hypotonic shock-induced fusion and recovery in both ypt4Δ and lvs1Δ cells, although recovery may be slightly delayed in ypt4Δ. Endocytic and secretory trafficking were not affected, but ypt4Δ and lvs1Δ strains were sensitive to neutral pH and CaCl2, consistent with vacuolar dysfunction. In addition to changes in vacuolar size, deletion of ypt4 also dramatically increased cell size, similar to tor1 mutants. These results implicate ypt4 and lvs1 in maintenance of vacuolar size and suggest that ypt4 may link vacuolar homeostasis to cell cycle progression.
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Irregular N-methyl-D-aspartate receptor (NMDAR) function is one of the main hypotheses employed to facilitate understanding of the underlying disease state of schizophrenia. Although direct agonism of the NMDAR has not yielded promising therapeutics, advances have been made by modulating the NMDAR co-agonist site which is activated by glycine and D-serine. One approach to activate the co-agonist site is to increase synaptic D-serine levels through inhibition of D-amino acid oxidase (DAO), the major catabolic clearance pathway for this and other D-amino acids. A number of DAO inhibitors have been developed but most have not entered clinical trials. One exception to this is sodium benzoate which has demonstrated efficacy in small trials of schizophrenia and Alzheimer's disease. Herein we provide data on the effect of sodium benzoate and an optimised Takeda compound, PGM030756 on ex vivo DAO enzyme occupancy and cerebellar D-serine levels in mice. Both compounds achieve high levels of enzyme occupancy; although lower doses of PGM030756 (1, 3 and 10 mg/kg) were required to achieve this compared to sodium benzoate (300, 1000 mg/kg). Cerebellar D-serine levels were increased by both agents with a delay of approximately 6 h after dosing before the peak effect was achieved. Our data and methods may be useful in understanding the effects of sodium benzoate that have been seen in clinical trials of schizophrenia and Alzheimer's disease and to support the potential clinical assessment of other DAO inhibitors, such as PGM030756, which demonstrate good enzyme occupancy and D-serine increases following administration of low oral doses.
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Cerebelo/metabolismo , Clorobencenos/farmacología , D-Aminoácido Oxidasa/antagonistas & inhibidores , D-Aminoácido Oxidasa/metabolismo , Inhibidores Enzimáticos/farmacología , Piridazinas/farmacología , Serina/metabolismo , Benzoato de Sodio/farmacología , Administración Oral , Animales , Biomarcadores/metabolismo , Clorobencenos/administración & dosificación , Clorobencenos/química , Cristalografía por Rayos X , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/química , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Piridazinas/administración & dosificación , Piridazinas/química , Benzoato de Sodio/administración & dosificación , Benzoato de Sodio/químicaRESUMEN
Free fatty acid receptor 2 (FFA2) is expressed on enteroendocrine L cells that release glucagon-like peptide 1 (GLP-1) and peptide YY (PYY) when activated by short-chain fatty acids (SCFAs). Functionally GLP-1 and PYY inhibit gut transit, increase glucose tolerance, and suppress appetite; thus, FFA2 has therapeutic potential for type 2 diabetes and obesity. However, FFA2-selective agonists have not been characterized in vivo. Compound 1 (Cpd 1), a potent FFA2 agonist, was tested for its activity on the following: GLP-1 release, modulation of intestinal mucosal ion transport and transit in wild-type (WT) and FFA2(-/-) tissue, and food intake and glucose tolerance in lean and diet-induced obese (DIO) mice. Cpd 1 stimulated GLP-1 secretion in vivo, but this effect was only detected with dipeptidyl peptidase IV inhibition, while mucosal responses were PYY, not GLP-1, mediated. Gut transit was faster in FFA2(-/-) mice, while Cpd 1 slowed WT transit and reduced food intake and body weight in DIO mice. Cpd 1 decreased glucose tolerance and suppressed plasma insulin in lean and DIO mice, despite FFA2(-/-) mice displaying impaired glucose tolerance. These results suggest that FFA2 inhibits intestinal functions and suppresses food intake via PYY pathways, with limited GLP-1 contribution. Thus, FFA2 may be an effective therapeutic target for obesity but not for type 2 diabetes.
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Ingestión de Alimentos/efectos de los fármacos , Tránsito Gastrointestinal/efectos de los fármacos , Intolerancia a la Glucosa/metabolismo , Intestinos/efectos de los fármacos , Péptido YY/metabolismo , Receptores de Superficie Celular/agonistas , Animales , Apetito/efectos de los fármacos , Células Cultivadas , Ingestión de Alimentos/fisiología , Tránsito Gastrointestinal/fisiología , Péptido 1 Similar al Glucagón/metabolismo , Mucosa Intestinal/metabolismo , Ratones , Ratones Obesos , Obesidad/metabolismoRESUMEN
INTRODUCTION: Acute respiratory distress syndrome (ARDS) is a major cause of mortality in intensive care units. As there is rising evidence about immuno-modulatory effects of lipid emulsions required for parenteral nutrition of ARDS patients, we sought to investigate whether infusion of conventional soybean oil (SO)-based or fish oil (FO)-based lipid emulsions rich in either n-6 or n-3 fatty acids, respectively, may influence subsequent pulmonary inflammation. METHODS: In a randomized controlled, single-blinded pilot study, forty-two volunteers received SO, FO, or normal saline for two days. Thereafter, volunteers inhaled pre-defined doses of lipopolysaccharide (LPS) followed by bronchoalveolar lavage (BAL) 8 or 24 h later. In the murine model of LPS-induced lung injury a possible involvement of resolvin E1 (RvE1) receptor ChemR23 was investigated. Wild-type and ChemR23 knockout mice were infused with both lipid emulsions and challenged with LPS intratracheally. RESULTS: In volunteers receiving lipid emulsions, the fatty acid profile in the plasma and in isolated neutrophils and monocytes was significantly changed. Adhesion of isolated monocytes to endothelial cells was enhanced after infusion of SO and reduced by FO, however, no difference of infusion on an array of surface adhesion molecules was detected. In neutrophils and monocytes, LPS-elicited generation of pro-inflammatory cytokines increased in the SO and decreased in the FO group. LPS inhalation in volunteers evoked an increase in neutrophils in BAL fluids, which decreased faster in the FO group. While TNF-α in the BAL was increased in the SO group, IL-8 decreased faster in the FO group. In the murine model of lung injury, effects of FO similar to the volunteer group observed in wild-type mice were abrogated in ChemR23 knockout mice. CONCLUSIONS: After infusion of conventional lipid emulsions, leukocytes exhibited increased adhesive and pro-inflammatory features. In contrast, FO-based lipid emulsions reduced monocyte adhesion, decreased pro-inflammatory cytokines, and neutrophil recruitment into the alveolar space possibly mediated by ChemR23-signaling. Lipid emulsions thus exert differential effects in human volunteers and mice in vivo. TRIAL REGISTRATION: DRKS00006131 at the German Clinical Trial Registry, 2014/05/14.
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Emulsiones Grasas Intravenosas/administración & dosificación , Inmunomodulación/efectos de los fármacos , Inmunomodulación/inmunología , Neumonía/tratamiento farmacológico , Neumonía/inmunología , Animales , Células Cultivadas , Aceites de Pescado/administración & dosificación , Humanos , Mediadores de Inflamación/antagonistas & inhibidores , Mediadores de Inflamación/inmunología , Ratones , Ratones Noqueados , Proyectos Piloto , Método Simple Ciego , Aceite de Soja/administración & dosificaciónRESUMEN
GPR81, which exhibits a high degree of homology with GPR109a, has been recently identified as a lactate receptor. Similar to GPR109a, the activation of GPR81 by lactate suppresses lipolysis, suggesting that GPR81 may be a potential drug target for treating dyslipidemia. In addition, the fact that GPR81 is expressed only in adipocytes, whereas GPR109a is expressed in various tissues and cells, including Langerhans cells, which are considered responsible for flushing, indicates that targeting GPR81 could lead to the development of antidyslipidemia agents with a reduced risk of this side effect. However, the pharmacological role of GPR81 remains largely unclear, mainly because of the lack of potent and selective surrogate GPR81 agonists suitable for in vivo studies. In the present study, we showed that lactate-induced suppression of lipolysis in explants of white adipose tissue (WAT) depends on the presence of GPR81. We also performed high-throughput screening (HTS) and identified four novel chemical clusters as GPR81 agonists. Chemical optimization of aminothiazole derivatives led to the discovery of a lead compound with improved potency. The compound inhibited lipolysis in differentiated 3T3-L1 adipocytes. Finally, intraperitoneal administration of this compound suppressed lipolysis in mice at doses that did not cause cutaneous flushing. This is the first description of a 50nM GPR81 selective agonist with in vivo efficacy, without the side effect, i.e., flushing. These results suggest that GPR81 is an attractive drug target for treating dyslipidemia without the risk of flushing.
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Adipocitos/efectos de los fármacos , Tejido Adiposo Blanco/efectos de los fármacos , Rubor/prevención & control , Hipolipemiantes/farmacología , Lipólisis/efectos de los fármacos , Receptores Acoplados a Proteínas G/agonistas , Tiazoles/farmacología , Células 3T3-L1 , Adipocitos/metabolismo , Tejido Adiposo Blanco/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Ensayos Analíticos de Alto Rendimiento , Hipolipemiantes/administración & dosificación , Hipolipemiantes/síntesis química , Inyecciones Intraperitoneales , Ácido Láctico/farmacología , Masculino , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores Acoplados a Proteínas G/deficiencia , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Relación Estructura-Actividad , Tiazoles/administración & dosificación , Tiazoles/síntesis química , TransfecciónRESUMEN
Maintaining or enhancing the productive capacity and resilience of rangeland ecosystems is critical for the continued support of people who depend on them for their livelihoods, especially in the face of climatic change. This is also necessary for the continued delivery of ecosystem services derived from rangelands for the broader benefit of societies around the world. Multi-paddock grazing management has been recommended since the mid-20th century as an important tool to adaptively manage rangelands ecosystems to sustain productivity and improve animal management. Moreover, there is much anecdotal evidence from producers that, if applied appropriately, multi-paddock grazing can improve forage and livestock production. By contrast, recent reviews of published rangeland-based grazing systems studies have concluded that, in general, field trials show no superiority of vegetation or animal production in multi-paddock grazing relative to continuous yearlong stocking of single-paddock livestock production systems. Our goal is to provide a framework for rangeland management decisions that support the productivity and resiliency of rangelands and then to identify why different perceptions exist among rangeland managers who have effectively used multi-paddock grazing systems and research scientists who have studied them. First, we discuss the ecology of grazed ecosystems under free-ranging herbivores and under single-paddock fenced conditions. Second, we identify five principles underpinning the adaptive management actions used by successful grazing managers and the ecological, physiological, and behavioral framework they use to achieve desired conservation, production, and financial goals. Third, we examine adaptive management principles needed to successfully manage rangelands subjected to varying environmental conditions. Fourth, we describe the differences between the interpretation of results of grazing systems research reported in the scientific literature and the results reported by successful grazing managers; we highlight the shortcomings of most of the previously conducted grazing systems research for providing information relevant for rangeland managers who aim to achieve desired environmental and economic goals. Finally, we outline knowledge gaps and present testable hypotheses to broaden our understanding of how planned multi-paddock grazing management can be used at the ranching enterprise scale to facilitate the adaptive management of rangelands under dynamic environmental conditions.
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Agricultura/métodos , Conservación de los Recursos Naturales/métodos , Ganado , Animales , Ecosistema , HerbivoriaRESUMEN
BACKGROUND: Topical Acyclovir has moderate efficacy on recurrent HSV symptoms, requiring repeat applications for several days. Topical Dynamiclear, which requires only a single dose application, may provide a more effective and convenient treatment option for symptomatic management of HSV. OBJECTIVES: The study assessed the comparative efficacy and tolerability of a single use, topical formulation containing copper sulfate pentahydrate and Hypericum perforatum that is marketed as Dynamiclear™ to a topical 5% Acyclovir cream standard preparation and use. METHODS: A prospective, randomized, multi-centered, comparative, open-label clinical study was conducted. A total of 149 participants between 18 and 55 years of age with active HSV-1 and HSV-2 lesions were recruited for the 14-day clinical trial. Participants were randomized into two groups: A (n=61), those receiving the Dynamiclear formulation, and B (n=59), those receiving 5% Acyclovir. Efficacy parameters were assessed via physical examination at baseline (day 1), day 2, 3, 8, and 14. Laboratory safety tests were conducted at baseline and on day 14. RESULTS: Use of the Dynamiclear formulation was found to have no significant adverse effects and was well tolerated by participants. All hematological and biochemical markers were within normal range for the Dynamiclear group. Statistically, odds for being affected by burning and stinging sensation were 1.9 times greater in the Acyclovir group in comparison to the Dynamiclear group. Similarly, the odds of being affected by symptoms of acute pain, erythema and vesiculation were 1.8, 2.4, and 4.4 times higher in the Acyclovir group in comparison to the Dynamiclear group. CONCLUSIONS: The Dynamiclear formulation was well tolerated, and efficacy was demonstrated in a number of measured parameters, which are helpful in the symptomatic management of HSV-1 and HSV-2 lesions in adult patients. Remarkably, the effects seen from this product came from a single application.
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Aciclovir/administración & dosificación , Sulfato de Cobre/administración & dosificación , Herpes Simple/tratamiento farmacológico , Herpesvirus Humano 1 , Herpesvirus Humano 2 , Hypericum , Aciclovir/efectos adversos , Administración Tópica , Adolescente , Adulto , Sulfato de Cobre/efectos adversos , Eritema/inducido químicamente , Eritema/diagnóstico , Femenino , Herpes Simple/patología , Humanos , Hypericum/efectos adversos , Masculino , Persona de Mediana Edad , Extractos Vegetales/administración & dosificación , Extractos Vegetales/efectos adversos , Estudios Prospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
Background The incidence of infection after posterior cervical spine surgery ranges from 0 to 18%. Higher rates have been reported after posterior procedures compared with anterior procedures, but these studies have been for small series. We report on our rate of surgical site infection (SSI) after posterior cervical spine surgery and the risk factors that influence these infections. Methods We retrospectively reviewed the records of 90 consecutive patients who underwent posterior cervical spine procedures at a major spinal referral center between 1998 and 2007. The main indications for surgery were trauma and degenerative conditions. Tumors and primary infections were excluded. Medical records of these patients were examined for evidence of SSI as diagnosed by Centers for Disease Control and Prevention criteria. Results Using stringent criteria for diagnosing SSI, we found 15 infected patients (16.67%). The postoperative use of a Philadelphia hard collar was found to be a significant risk factor for SSI with a relative risk of 15.30 (95% confidence interval 2.10 to 111.52). Almost half of infected patients (47%) required reoperation for wound debridement, with four requiring skin flap closure. All 15 patients had successful outcomes with complete resolution of their infection. Conclusions This study confirms a high incidence of SSI after posterior cervical surgery. The most significant risk factors for SSI were found to be a traumatic etiology and postoperative use of a collar. We believe it is important to develop strategies to minimize the risk of infection after posterior cervical surgery, which include questioning the postoperative use of collars.
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PURPOSE: The aim of this study was to determine whether compression garments improve intermittent-sprint performance and aid performance or self-reported recovery from high-intensity efforts on consecutive days. METHODS: Following familiarization, 14 male rugby players performed two randomized testing conditions (with or without garments) involving consecutive days of a simulated team sport exercise protocol, separated by 24 h of recovery within each condition and 2 weeks between conditions. Each day involved an 80-min high-intensity exercise circuit, with exercise performance determined by repeated 20-m sprints and peak power on a cart dynamometer (single-man scrum machine). Measures of nude mass, heart rate, skin and tympanic temperature, and blood lactate (La-) were recorded throughout each day; also, creatine kinase (CK) and muscle soreness were recorded each day and 48 h following exercise. RESULTS: No differences (P=.20 to 0.40) were present between conditions on either day of the exercise protocol for repeated 20-m sprint efforts or peak power on a cart dynamometer. Heart rate, tympanic temperature, and body mass did not significantly differ between conditions; however, skin temperature was higher under the compression garments. Although no differences (P=.50) in La- or CK were present, participants felt reduced levels of perceived muscle soreness in the ensuing 48 h postexercise when wearing the garments (2.5+/-1.7 vs 3.5+/-2.1 for garment and control; P=.01). CONCLUSIONS: The use of compression garments did not improve or hamper simulated team-sport activity on consecutive days. Despite benefits of reduced self-reported muscle soreness when wearing garments during and following exercise each day, no improvements in performance or recovery were apparent.