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Food emulsifiers like glycerol monostearate (G) and Tween 80 (TW) are commonly used to help formation and maintain stability of emulsions. However, certain food contaminants and emulsifiers often co-occur in the same food item due to food culture and cooking methods. For this reason, the present study investigated interaction of toxic effect of emulsifiers (G and TW) and process contaminants (acrylamide (AA) and benzo [a]pyrene (BAP)) on zebrafish. Adult zebrafish were exposed to emulsifiers, food contaminants, or the combination through diet for 2 h and 7 days. Oxidative stress and inflammation caused by food contaminants were increased when food emulsifiers were present. These combined treatments also induced more severe morphological changes than the contaminant alone treatments. In the gut, disruption of villi structure and increased number of goblet cells was observed and in the liver there were increased lipid deposition, infiltration of immune cells, glycogen depletion and focal necrosis. Increased accumulation of AA and BAP in the liver and gut were detected after addition of emulsifiers, suggesting that emulsifiers can enhance absorption of diet-borne contaminants. Our results showed food emulsifiers and contaminants can interact synergistically and increase risk.
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Emulsificantes , Contaminação de Alimentos , Inflamação , Estresse Oxidativo , Peixe-Zebra , Animais , Estresse Oxidativo/efeitos dos fármacos , Emulsificantes/toxicidade , Inflamação/induzido quimicamente , Inflamação/metabolismo , Contaminação de Alimentos/análise , Benzo(a)pireno/toxicidade , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Acrilamida/toxicidade , Polissorbatos/toxicidadeRESUMO
Contaminants such as heavy metals and polycyclic aromatic hydrocarbons (PAHs) can be released from asphalt pavement and transported through stormwater runoff to nearby water bodies, leading to water pollution and potential harm to living aquatic animals. This study characterizes the heavy metal and PAH leaching from various asphalt paving materials and their potential ecotoxicological effects on zebrafish Danio rerio. Artificial runoffs were prepared in the laboratory concerning the effects of water, temperature, and traffic. The concentrations of heavy metals and PAHs in the leachates were quantified, while the toxicity assessment encompassed mortality, metal stress, PAH toxicity, inflammation, carcinogenicity, and oxidative damage. Gene expressions of related proteins or transcription factors were assessed, including metallothionines, aryl hydrocarbon receptors, interleukin-1ß, interleukin-10, nuclear factor-κB, tumor necrosis factor-α, tumor suppressor p53, heat shock protein 70, and reactive oxygen species (ROS). The findings demonstrate that leachates from asphalt pavements containing waste bottom ash, crumb rubber, or specific chemicals could induce notable stress and inflammation responses in zebrafish. In addition, potential carcinogenic effects and the elevation of ROS were identified within certain treatment groups. This study represents the first attempt to assess the ecotoxicity of pavement leachates employing a live fish model, thereby improving the current understanding of the environmental impact of asphalt pavements.
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Hidrocarbonetos , Metais Pesados , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Peixe-Zebra , Animais , Poluentes Químicos da Água/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos/toxicidade , Metais Pesados/toxicidade , Ecotoxicologia , Materiais de Construção , Monitoramento AmbientalRESUMO
Food products simultaneously containing both food contaminants and emulsifiers are common in baked products, coffee and chocolate. Little is known regarding how food contaminants and emulsifiers interact and alter toxicity. Recent studies have shown that while emulsifiers themselves have little toxicity, they could cause changes in the gut microenvironment and lead to issues such as increased uptake of allergens. This study examined toxic effect of two common process contaminants acrylamide (AA) and benzo [a]pyrene (BAP) combined with food emulsifiers polyoxyethylene sorbitan monooleate (TW) or glycerol monostearate (G). In liver cell line HepG2 and gastrointestinal cell lines HIEC6 and Caco-2, toxicities of AA and BAP were increased by TW but not by G as indicated by decrease in IC50 values. Addition of TW also exacerbated gene expression changes caused by AA or BAP. Cellular uptake and cell membrane permeability were enhanced by TW but not by G, but tight junction proteins of Caco-2 monolayer was impacted by both emulsifiers. These results suggested that TW could increase toxicity of AA and BAP through increasing cell permeability thus chemical uptake and potentially through other interactions. The study is to draw the attention of regulators on the potential synergistic interaction of co-occurring chemicals in food.
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Chocolate , Alimentos , Humanos , Células CACO-2 , Café , Transporte Biológico , Acrilamida/toxicidade , Benzo(a)pirenoRESUMO
BACKGROUND: Head and neck squamous cell cancer (HNSCC) occurs at higher rates among persons with HIV (PWH). This study compares the impact of sociodemographic and clinicopathologic characteristics on outcomes among PWH-HNSCC compared with HNSCC patients without HIV. METHODS: Patient data from HNSCC individuals were collected at a single academic hospital center between 2002 and 2018. Forty-eight patients with HIV (HIV-HNSCC) and 2894 HNSCC patients without HIV were included. Multivariate analysis determined predictors of survival using Cox proportional hazards regression model. HIV-positive and -negative tumors were analyzed by quantitative immunofluorescence for expression of CD4, CD8, CD20 and PD-L1. RESULTS: HIV-HNSCC patients had a lower median overall survival than HNSCC patients without HIV (34 [18-84] vs 94 [86-103] months; P < .001). In multivariate analysis that included age, sex, race/ethnicity, stage, site, tobacco use, time to treatment initiation, and insurance status, HIV was an independent predictor of poorer survival, with a hazard ratio of 1.98 (95% CI: 1.32-2.97; P < .001). PWH with human papillomavirus (HPV)-positive oropharyngeal tumors also had worse prognosis than HPV-positive oropharyngeal tumors in the population without HIV (P < .001). The tumor microenvironment among HIV-HNSCC patients revealed lower intratumoral CD8 infiltration among HIV+ HPV+ tumors compared with HIV- HPV+ tumors (P = .04). CONCLUSIONS: HIV-HNSCC patients had worse prognosis than the non-HIV population, with HIV being an independent predictor of poor clinical outcomes when accounting for important sociodemographic and clinicopathologic factors. Our findings highlight differences in tumor biology that require further detailed characterization in large cohorts and increased inclusion of PWH in immunotherapy trials.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/complicações , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , HIV , Infecções por Papillomavirus/epidemiologia , Neoplasias de Cabeça e Pescoço/complicações , Prognóstico , Microambiente TumoralRESUMO
Selenium nanoparticles (SeNPs) are a novel elemental form selenium and often reported to possess beneficial bioactivities such as anticancer, promoting bone growth and immunomodulation. Our previous study demonstrated that chitosan-stabilized SeNPs have strong activity in immunomodulation. However, the mechanism underlying the immunomodulation of SeNPs is still unknown. The aim of this study is to identify the molecular mechanisms involved in SeNP-induced immunomodulation. Using zebrafish, as a common immunological animal model with a highly conserved molecular mechanism with other vertebrates, we conducted serum proteomic and tissue transcriptome analyses on individuals fed with SeNP in healthy or disease conditions. We also compared differences between SeNPs and an exogenous antioxidant Trolox in immune activity and redox regulation. Our results suggest that the immunomodulation activity was highly related to antioxidant activity and lipid metabolism. Interestingly, the biological functions enhanced by SeNP were almost identical in the healthy and disease conditions. However, while the SeNP was suppressing ROS in healthy individuals, it promoted ROS formation during disease condition. This might be related to the defense mechanism against pathogens. SOD and NFkß appeared to be the key molecular switch changing effect of SeNPs when individuals undergo infection, indicating the close relationship between immune and redox regulation.
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Insulin analogs have been developed to treat diabetes with focus primarily on improving the time action profile without affecting ligand-receptor interaction or functional selectivity. As a result, inherent liabilities (e.g. hypoglycemia) of injectable insulin continue to limit the true therapeutic potential of related agents. Insulin dimers were synthesized to investigate whether partial agonism of the insulin receptor (IR) tyrosine kinase is achievable, and to explore the potential for tissue-selective systemic insulin pharmacology. The insulin dimers induced distinct IR conformational changes compared to native monomeric insulin and substrate phosphorylation assays demonstrated partial agonism. Structurally distinct dimers with differences in conjugation sites and linkers were prepared to deliver desirable IR partial agonist (IRPA). Systemic infusions of a B29-B29 dimer in vivo revealed sharp differences compared to native insulin. Suppression of hepatic glucose production and lipolysis were like that attained with regular insulin, albeit with a distinctly shallower dose-response. In contrast, there was highly attenuated stimulation of glucose uptake into muscle. Mechanistic studies indicated that IRPAs exploit tissue differences in receptor density and have additional distinctions pertaining to drug clearance and distribution. The hepato-adipose selective action of IRPAs is a potentially safer approach for treatment of diabetes.
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Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Receptor de Insulina/agonistas , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Aloxano/administração & dosagem , Aloxano/toxicidade , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Células CHO , Cricetulus , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/metabolismo , Células HEK293 , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Lipólise/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Ratos , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Suínos , Porco MiniaturaRESUMO
INTRODUCTION/OBJECTIVES: Musculoskeletal ultrasound (MSUS) has been extensively studied by rheumatologists in Europe and the Americas, but less is known about MSUS use in Asia. Our hypothesis is that MSUS use is less prevalent in China as compared with its Western counterparts. This study reports the most up-to-date recommendations for MSUS use in rheumatology globally and is also the first study to characterize the current practices, training, and perceptions regarding MSUS of rheumatologists in China. METHOD: A 43-question survey was designed and distributed via mobile application to members of the Chinese Rheumatology Association, primarily to investigate the current prevalence and utilization of MSUS in China. Statistical analyses included the use of chi-square tests and independent-samples t tests, with p values less than 0.05 considered statistically significant. RESULTS: The results showed low rates of MSUS training (129/528, 24%) and current MSUS use (89/524, 17%) in China. However, there was a high level of interest in learning MSUS, especially among younger respondents. Lack of access to training programs and user variability in skill were seen as significant barriers to the uptake of MSUS. CONCLUSIONS: Despite low rates of MSUS training and utilization, the vast majority of respondents believe that MSUS should become a standard clinical tool in rheumatology, and there was great interest in undergoing training. Importantly, lack of access to MSUS training programs and user variability in skill were seen as significant obstacles to the more widespread use of MSUS, which suggests a need for more standardized, high-quality MSUS training in China. Key Points ⢠A low percentage of Chinese rheumatologists (17%) currently use MSUS. ⢠Chinese rheumatologists expressed a high level of interest in obtaining MSUS training. ⢠The greatest perceived obstacle to more widespread MSUS use is the lack of training programs.
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Doenças Musculoesqueléticas , Reumatologia , Ásia , China , Competência Clínica , Europa (Continente) , Humanos , Reumatologistas , Reumatologia/educação , UltrassonografiaRESUMO
BACKGROUND: Vaccination is the most cost-effective medical intervention known to prevent morbidity and mortality. However, data are limited on the effectiveness of residency programs in delivering immunization knowledge and skills to trainees. The authors sought to describe the immunization competency needs of medical residents at the University of Toronto (UT), and to develop and evaluate a pilot immunization curriculum. METHODS: Residents at the University of Toronto across nine specialties were recruited to attend a pilot immunization workshop in November 2018. Participants completed a questionnaire before and after the workshop to assess immunization knowledge and compare baseline change. Feedback was also surveyed on the workshop content and process. Descriptive statistics were performed on the knowledge questionnaire and feedback survey. A paired sample T-test compared questionnaire answers before and after the workshop. Descriptive coding was used to identify themes from the feedback survey. RESULTS: Twenty residents from at least six residencies completed the pre-workshop knowledge questionnaire, seventeen attended the workshop, and thirteen completed the post-workshop questionnaire. Ninety-five percent (19/20) strongly agreed that vaccine knowledge was important to their career, and they preferred case-based teaching. The proportion of the thirty-four knowledge questions answered correctly increased from 49% before the workshop to 67% afterwards, with a mean of 2.24 (CI: 1.43, 3.04) more correct answers (P < 0.001). Sixteen residents completed the post-workshop feedback survey. Three themes emerged: first, they found the content specific and practical; second, they wanted more case-based learning and for the workshop to be longer; and third, they felt the content and presenters were of high quality. CONCLUSIONS: Findings from this study suggest current immunization training of UT residents does not meet their training competency requirements. The study's workshop improved participants' immunization knowledge. The information from this study could be used to develop residency immunization curriculum at UT and beyond.
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Internato e Residência , Currículo , Educação de Pós-Graduação em Medicina , Retroalimentação , Humanos , Imunização , VacinaçãoRESUMO
Ceramides contribute to the lipotoxicity that underlies diabetes, hepatic steatosis, and heart disease. By genetically engineering mice, we deleted the enzyme dihydroceramide desaturase 1 (DES1), which normally inserts a conserved double bond into the backbone of ceramides and other predominant sphingolipids. Ablation of DES1 from whole animals or tissue-specific deletion in the liver and/or adipose tissue resolved hepatic steatosis and insulin resistance in mice caused by leptin deficiency or obesogenic diets. Mechanistic studies revealed ceramide actions that promoted lipid uptake and storage and impaired glucose utilization, none of which could be recapitulated by (dihydro)ceramides that lacked the critical double bond. These studies suggest that inhibition of DES1 may provide a means of treating hepatic steatosis and metabolic disorders.
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Ceramidas/metabolismo , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Resistência à Insulina/genética , Proteínas de Membrana/genética , Oxirredutases/genética , Animais , Ceramidas/química , Ceramidas/genética , Dieta Hiperlipídica/efeitos adversos , Deleção de Genes , Leptina/deficiência , Camundongos , Camundongos Mutantes , Esfingolipídeos/química , Esfingolipídeos/metabolismoRESUMO
OBJECTIVES: GPR142, which is highly expressed in pancreatic islets, has recently been deorphanized as a receptor for aromatic amino acids; however, its physiological role and pharmacological potential is unclear. METHODS AND RESULTS: We find that GPR142 is expressed not only in ß- but also in α-cells of the islets as well as in enteroendocrine cells, and we confirm that GPR142 is a highly selective sensor of essential aromatic amino acids, in particular Trp and oligopeptides with N-terminal Trp. GPR142 knock-out mice displayed a very limited metabolic phenotype but demonstrated that L-Trp induced secretion of pancreatic and gut hormones is mediated through GPR142 but that the receptor is not required for protein-induced hormone secretion. A synthetic GPR142 agonist stimulated insulin and glucagon as well as GIP, CCK, and GLP-1 secretion. In particular, GIP secretion was sensitive to oral administration of the GPR142 agonist an effect which in contrast to the other hormones was blocked by protein load. Oral administration of the GPR142 agonist increased [3H]-2-deoxyglucose uptake in muscle and fat depots mediated through insulin action while it lowered liver glycogen conceivably mediated through glucagon, and, consequently, it did not lower total blood glucose. Nevertheless, acute administration of the GPR142 agonist strongly improved oral glucose tolerance in both lean and obese mice as well as Zucker fatty rat. Six weeks in-feed chronic treatment with the GPR142 agonist did not affect body weight in DIO mice, but increased energy expenditure and carbohydrate utilization, lowered basal glucose, and improved insulin sensitivity. CONCLUSIONS: GPR142 functions as a sensor of aromatic amino acids, controlling GIP but also CCK and GLP-1 as well as insulin and glucagon in the pancreas. GPR142 agonists could have novel interesting potential in modifying metabolism through a balanced action of gut hormones as well as both insulin and glucagon.
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Ilhotas Pancreáticas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Aminoácidos Aromáticos/metabolismo , Animais , Glicemia/metabolismo , Glucagon/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Células Secretoras de Glucagon/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Ratos , Ratos Zucker , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/metabolismo , Receptores Acoplados a Proteínas G/biossíntese , Receptores dos Hormônios Gastrointestinais/metabolismo , Receptores de Glucagon/metabolismo , Triptofano/metabolismoRESUMO
We report new SSTR5 antagonists with enhanced potency, subtype selectivity, and minimal off-target activities as compared to previously reported compounds. Starting from the reported SSTR5 antagonist 1, we systematically surveyed changes in the central core and head piece while maintaining the diphenyl tail group constant. From this study the azaspirodecanone 10 emerged as a new highly potent and selective SSTR5 antagonist. Compound 10 lowered glucose excursion by 94% in an oral glucose tolerance test (OGTT) in mice following a 3 mg/kg oral dose. The compound increased both total and active circulating incretin hormone GLP-1 levels in mice at a dose of 10 mg/kg. A synergistic effect was also demonstrated when compound 10 was coadministered with a DPP-4 inhibitor, substantially increasing circulating active GLP-1[7-36] amide and insulin in response to a glucose challenge.
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Insulin-induced hypoglycemia in diabetes is associated with impaired glucagon secretion. In this study, we tested whether stimulation of GPR119, a G-protein-coupled receptor expressed in pancreatic islet as well as enteroendocrine cells and previously shown to stimulate insulin and incretin secretion, might enhance glucagon secretion during hypoglycemia. In the study, GPR119 agonists were applied to isolated islets or perfused pancreata to assess insulin and glucagon secretion during hypoglycemic or hyperglycemic conditions. Insulin infusion hypoglycemic clamps were performed with or without GPR119 agonist pretreatment to assess glucagon counterregulation in healthy and streptozotocin (STZ)-induced diabetic rats, including those exposed to recurrent bouts of insulin-induced hypoglycemia that leads to suppression of hypoglycemia-induced glucagon release. Hypoglycemic clamp studies were also conducted in GPR119 knockout (KO) mice to evaluate whether the pharmacological stimulatory actions of GPR119 agonists on glucagon secretion during hypoglycemia were an on-target effect. The results revealed that GPR119 agonist-treated pancreata or cultured islets had increased glucagon secretion during low glucose perfusion. In vivo, GPR119 agonists also significantly increased glucagon secretion during hypoglycemia in healthy and STZ-diabetic rats, a response that was absent in GPR119 KO mice. In addition, impaired glucagon counterregulatory responses were restored by a GPR119 agonist in STZ-diabetic rats that were exposed to antecedent bouts of hypoglycemia. Thus, GPR119 agonists have the ability to pharmacologically augment glucagon secretion, specifically in response to hypoglycemia in diabetic rodents. Whether this effect might serve to diminish the occurrence and severity of iatrogenic hypoglycemia during intensive insulin therapy in patients with diabetes remains to be established.
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Glucagon/metabolismo , Hipoglicemia/induzido quimicamente , Hipoglicemia/metabolismo , Insulina/efeitos adversos , Receptores Acoplados a Proteínas G/agonistas , Adulto , Animais , Células Cultivadas , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Teste de Tolerância a Glucose , Humanos , Hipoglicemiantes/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Ratos , Ratos Wistar , Receptores Acoplados a Proteínas G/genética , Estreptozocina , Adulto JovemRESUMO
Hypoglycemia is commonly associated with insulin therapy, limiting both its safety and efficacy. The concept of modifying insulin to render its glucose-responsive release from an injection depot (of an insulin complexed exogenously with a recombinant lectin) was proposed approximately 4 decades ago but has been challenging to achieve. Data presented here demonstrate that mannosylated insulin analogs can undergo an additional route of clearance as result of their interaction with endogenous mannose receptor (MR), and this can occur in a glucose-dependent fashion, with increased binding to MR at low glucose. Yet, these analogs retain capacity for binding to the insulin receptor (IR). When the blood glucose level is elevated, as in individuals with diabetes mellitus, MR binding diminishes due to glucose competition, leading to reduced MR-mediated clearance and increased partitioning for IR binding and consequent glucose lowering. These studies demonstrate that a glucose-dependent locus of insulin clearance and, hence, insulin action can be achieved by targeting MR and IR concurrently.
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Glucose/metabolismo , Hipoglicemia/tratamento farmacológico , Insulina/farmacologia , Animais , Antígenos CD , Glicemia , Linhagem Celular , Diabetes Mellitus Tipo 2 , Modelos Animais de Doenças , Hipoglicemiantes/farmacologia , Lectinas Tipo C/efeitos dos fármacos , Fígado/patologia , Macrófagos , Masculino , Receptor de Manose , Lectinas de Ligação a Manose/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Receptor de Insulina/efeitos dos fármacos , Receptores de Superfície Celular/efeitos dos fármacosRESUMO
This article was migrated. The article was marked as recommended. Background: Structured feedback is an important component of learning and assessment and is highly valued by candidates. Unfortunately, item specific feedback is generally not feasible for high stakes professional assessments due to the high cost of item development and the need to maintain stable assessment performance characteristics. In a high stakes assessment of fetal surveillance knowledge, we sought to use graphical item mapping to allow informative candidate feedback without compromising the item bank. Methods: We developed Graphical Item Maps (GIMs) to display individual candidate performance in the Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) Fetal Surveillance Education Program (FSEP) multiple-choice question assessment. GIMs use item and person parameter estimates from Item Response Theory (IRT) models to map the interaction between a test taker and assessment tasks of varying difficulty. Results: It is both feasible and relatively simple to provide GIMs for individual candidate feedback. Operational examples are presented from the RANZCOG FSEP assessment. This paper demonstrates how test takers and educators might use GIMs as a form of assessment feedback. Conclusions: Graphical Item Maps are a useful and insightful assessment feedback tool for clinical practitioners partaking in a high stakes professional education and assessment program. They might be usefully employed in similar healthcare professional assessments to inform directed learning.
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Insulin has a narrow therapeutic index, reflected in a small margin between a dose that achieves good glycemic control and one that causes hypoglycemia. Once injected, the clearance of exogenous insulin is invariant regardless of blood glucose, aggravating the potential to cause hypoglycemia. We sought to create a "smart" insulin, one that can alter insulin clearance and hence insulin action in response to blood glucose, mitigating risk for hypoglycemia. The approach added saccharide units to insulin to create insulin analogs with affinity for both the insulin receptor (IR) and mannose receptor C-type 1 (MR), which functions to clear endogenous mannosylated proteins, a principle used to endow insulin analogs with glucose responsivity. Iteration of these efforts culminated in the discovery of MK-2640, and its in vitro and in vivo preclinical properties are detailed in this report. In glucose clamp experiments conducted in healthy dogs, as plasma glucose was lowered stepwise from 280 mg/dL to 80 mg/dL, progressively more MK-2640 was cleared via MR, reducing by â¼30% its availability for binding to the IR. In dose escalations studies in diabetic minipigs, a higher therapeutic index for MK-2640 (threefold) was observed versus regular insulin (1.3-fold).
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Diabetes Mellitus Tipo 1/tratamento farmacológico , Desenho de Fármacos , Hipoglicemiantes/uso terapêutico , Insulina Regular Humana/análogos & derivados , Lectinas Tipo C/agonistas , Lectinas de Ligação a Manose/agonistas , Receptor de Insulina/agonistas , Receptores de Superfície Celular/agonistas , Animais , Animais Endogâmicos , Ligação Competitiva , Células CHO , Cricetulus , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/metabolismo , Cães , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Humanos , Hiperglicemia/prevenção & controle , Hipoglicemia/induzido quimicamente , Hipoglicemia/prevenção & controle , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacocinética , Insulina Regular Humana/efeitos adversos , Insulina Regular Humana/farmacocinética , Insulina Regular Humana/uso terapêutico , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Ligantes , Masculino , Receptor de Manose , Lectinas de Ligação a Manose/genética , Lectinas de Ligação a Manose/metabolismo , Taxa de Depuração Metabólica , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapêutico , Suínos , Porco MiniaturaRESUMO
AMP-activated protein kinase (AMPK) plays an essential role as a cellular energy sensor and master regulator of metabolism in eukaryotes. Dysregulated lipid and carbohydrate metabolism resulting from insulin resistance leads to hyperglycemia, the hallmark of type 2 diabetes mellitus (T2DM). While pharmacological activation of AMPK is anticipated to improve these parameters, the discovery of selective, direct activators has proven challenging. We now describe a hit-to-lead effort resulting in the discovery of a potent and selective class of benzimidazole-based direct AMPK activators, exemplified by 5-((5-([1,1'-biphenyl]-4-yl)-6-chloro-1H-benzo[d]imidazol-2-yl)oxy)-2-methylbenzoic acid, 42 (MK-3903). Compound 42 exhibited robust target engagement in mouse liver following oral dosing, leading to improved lipid metabolism and insulin sensitization in mice.
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Proteínas Quinases Ativadas por AMP/metabolismo , Benzimidazóis/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Administração Oral , Animais , Benzimidazóis/administração & dosagem , Benzimidazóis/uso terapêutico , Descoberta de Drogas , Resistência à Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , CamundongosRESUMO
BACKGROUND: Patients with limited English proficiency (LEP) experience poorer quality care and more adverse events in hospital. Consequently, there is interest in understanding the role of professional medical interpreters in efforts to improve patient safety. OBJECTIVE: To describe the views of professional medical interpreters on their role in the delivery of safe patient care. DESIGN: Qualitative analysis of in-depth semi-structured interviews. PARTICIPANTS: 15 professional medical interpreters affiliated with the Healthcare Interpretation Network in Toronto, Canada. APPROACH: Participants' views on their role in patient safety were analyzed and organized into themes. KEY RESULTS: Professional medical interpreters described being uniquely situated to identify and prevent adverse events involving patients with LEP by: 1) facilitating communication and enhancing patients' comprehension, 2) giving voice to patients, and 3) speaking up about safety concerns. Participants described a tension between 'speaking up' and interpreters' ethical imperative to remain impartial. Interpreters also highlighted several challenges, including 4) medical hierarchy and healthcare providers' limited knowledge of the role of interpreters. These challenges introduced safety issues if providers asked interpreters to act outside of their scope of practice. CONCLUSIONS: Our study found that professional medical interpreters view their work as integral to the delivery of safe care to patients with LEP. In order to effectively engage in patient safety efforts together, interpreters and providers require a mutual understanding of their roles. Team hierarchy and limited provider knowledge of the role of interpreters can introduce safety concerns. In addition, interpreters describe a tension between "speaking up" about patient safety and the need for interpreters to remain impartial when facilitating communication. Healthcare institutions, providers, and interpreters must engage in discussion on how to best to "speak up" and integrate interpreters into safety efforts. Importantly, the benefits of partnering with interpreters can only be realized when providers consistently use their services.
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Atenção à Saúde , Idioma , Segurança do Paciente , Tradução , Feminino , Humanos , Masculino , OntárioRESUMO
GPR40 and GPR120 are fatty acid sensors that play important roles in glucose and energy homeostasis. GPR40 potentiates glucose-dependent insulin secretion and demonstrated in clinical studies robust glucose lowering in type 2 diabetes. GPR120 improves insulin sensitivity in rodents, albeit its mechanism of action is not fully understood. Here, we postulated that the antidiabetic efficacy of GPR40 could be enhanced by coactivating GPR120. A combination of GPR40 and GPR120 agonists in db/db mice, as well as a single molecule with dual agonist activities, achieved superior glycemic control compared with either monotherapy. Compared with a GPR40 selective agonist, the dual agonist improved insulin sensitivity in ob/ob mice measured by hyperinsulinemic-euglycemic clamp, preserved islet morphology, and increased expression of several key lipolytic genes in adipose tissue of Zucker diabetic fatty rats. Novel insights into the mechanism of action for GPR120 were obtained. Selective GPR120 activation suppressed lipolysis in primary white adipocytes, although this effect was attenuated in adipocytes from obese rats and obese rhesus, and sensitized the antilipolytic effect of insulin in rat and rhesus primary adipocytes. In conclusion, GPR120 agonism enhances insulin action in adipose tissue and yields a synergistic efficacy when combined with GPR40 agonism.