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1.
Diabetologia ; 65(7): 1179-1184, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35501400

RESUMO

AIMS/HYPOTHESIS: A key unanswered question in type 1 diabetes is whether beta cells initiate their own destruction or are victims of an aberrant immune response (beta cell suicide or homicide?). To investigate this, we assessed islet autoantibodies in individuals with congenital beta cell defects causing neonatal diabetes mellitus (NDM). METHODS: We measured autoantibodies to GAD (GADA), islet antigen-2 (IA-2A) and zinc transporter 8 (ZnT8A) in 242 individuals with NDM (median age diagnosed 1.8 months [IQR 0.39-2.9 months]; median age collected 4.6 months [IQR 1.8-27.6 months]; median diabetes duration 2 months [IQR 0.6-23 months]), including 75 whose NDM resulted from severe beta cell endoplasmic reticulum (ER) stress. As a control cohort we also tested samples from 69 diabetes-free individuals (median age collected 9.9 months [IQR 9.0-48.6 months]) for autoantibodies. RESULTS: We found low prevalence of islet autoantibodies in individuals with monogenic NDM; 13/242 (5.4% [95% CI 2.9, 9.0%]) had detectable GADA, IA-2A and/or ZnT8A. This was similar to the proportion in the control participants who did not have diabetes (1/69 positive [1.4%, 95% CI 0.03, 7.8%], p=0.3). Importantly, monogenic individuals with beta cell ER stress had a similar rate of GADA/IA-2A/ZnT8A positivity to non-ER stress aetiologies (2.7% [95% CI 0.3, 9.3%] vs 6.6% [95% CI 3.3, 11.5%] p=0.4). We observed no association between islet autoimmunity and genetic risk, age at testing (including 30 individuals >10 years at testing) or diabetes duration (p>0.4 for all). CONCLUSIONS/INTERPRETATION: Our data support the hypothesis that beta cell stress/dysfunction alone does not lead to the production of islet autoantibodies, even in the context of high-risk HLA types. This suggests that additional factors are required to trigger an autoimmune response towards beta cells.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Autoanticorpos , Autoimunidade/genética , Biomarcadores , Pré-Escolar , Diabetes Mellitus Tipo 1/metabolismo , Glutamato Descarboxilase , Humanos , Lactente , Recém-Nascido , Células Secretoras de Insulina/metabolismo , Fatores de Risco
2.
Environ Sci Technol ; 56(10): 6078-6090, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35486899

RESUMO

Researchers have developed numerous per- and polyfluoroalkyl substances (PFAS)-free aqueous film-forming foam (AFFF) formulations to replace PFAS-containing AFFF used for fire suppression. As part of the Department of Defense's Strategic Environmental Research and Development Program (SERDP), we examined the direct lethal effects of seven PFAS-free AFFF and a PFAS-containing AFFF on 14 aquatic species using a series of lethal concentration (LC50) tests. We assessed the LC10, LC50, and LC90 values using log-logistic and logit analyses. Across all aquatic species tested, we discovered that exposure to at least one PFAS-free AFFF was more or as toxic as exposure to the PFAS-containing AFFF. For most cases, National Foam Avio F3 Green KHC 3% and Buckeye Platinum Plus C6MILSPEC 3% were the most and least toxic formulations, respectively. Moreover, we found consistency among results from multiple experiments using the same minnow species (Pimephales promelas) and among closely related taxa (e.g., daphnids, amphibians). Lastly, the LC50 values for AFFF formulations trended lower for tested marine species as compared to those of freshwater species. These results dramatically increase the current knowledge on the potentially toxic effects of AFFF but also highlight the need for additional research and the development of new PFAS-free AFFF that are more "ecologically friendly" than those containing persistent PFAS.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Aerossóis , Fluorocarbonos/análise , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
3.
PLoS Comput Biol ; 16(8): e1008044, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32797044

RESUMO

Genetic studies have recently highlighted the importance of fat distribution, as well as overall adiposity, in the pathogenesis of obesity-associated diseases. Using a large study (n = 1,288) from 4 independent cohorts, we aimed to investigate the relationship between mean adipocyte area and obesity-related traits, and identify genetic factors associated with adipocyte cell size. To perform the first large-scale study of automatic adipocyte phenotyping using both histological and genetic data, we developed a deep learning-based method, the Adipocyte U-Net, to rapidly derive mean adipocyte area estimates from histology images. We validate our method using three state-of-the-art approaches; CellProfiler, Adiposoft and floating adipocytes fractions, all run blindly on two external cohorts. We observe high concordance between our method and the state-of-the-art approaches (Adipocyte U-net vs. CellProfiler: R2visceral = 0.94, P < 2.2 × 10-16, R2subcutaneous = 0.91, P < 2.2 × 10-16), and faster run times (10,000 images: 6mins vs 3.5hrs). We applied the Adipocyte U-Net to 4 cohorts with histology, genetic, and phenotypic data (total N = 820). After meta-analysis, we found that mean adipocyte area positively correlated with body mass index (BMI) (Psubq = 8.13 × 10-69, ßsubq = 0.45; Pvisc = 2.5 × 10-55, ßvisc = 0.49; average R2 across cohorts = 0.49) and that adipocytes in subcutaneous depots are larger than their visceral counterparts (Pmeta = 9.8 × 10-7). Lastly, we performed the largest GWAS and subsequent meta-analysis of mean adipocyte area and intra-individual adipocyte variation (N = 820). Despite having twice the number of samples than any similar study, we found no genome-wide significant associations, suggesting that larger sample sizes and a homogenous collection of adipose tissue are likely needed to identify robust genetic associations.


Assuntos
Adipócitos , Aprendizado de Máquina , Obesidade , Adipócitos/classificação , Adipócitos/citologia , Tecido Adiposo/fisiologia , Adulto , Índice de Massa Corporal , Tamanho Celular , Biologia Computacional/métodos , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Obesidade/epidemiologia , Obesidade/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética
4.
Diabetologia ; 63(12): 2605-2615, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33029656

RESUMO

AIMS/HYPOTHESIS: Diabetes diagnosed at <6 months of age is usually monogenic. However, 10-15% of affected infants do not have a pathogenic variant in one of the 26 known neonatal diabetes genes. We characterised infants diagnosed at <6 months of age without a pathogenic variant to assess whether polygenic type 1 diabetes could arise at early ages. METHODS: We studied 166 infants diagnosed with type 1 diabetes at <6 months of age in whom pathogenic variants in all 26 known genes had been excluded and compared them with infants with monogenic neonatal diabetes (n = 164) or children with type 1 diabetes diagnosed at 6-24 months of age (n = 152). We assessed the type 1 diabetes genetic risk score (T1D-GRS), islet autoantibodies, C-peptide and clinical features. RESULTS: We found an excess of infants with high T1D-GRS: 38% (63/166) had a T1D-GRS >95th centile of healthy individuals, whereas 5% (8/166) would be expected if all were monogenic (p < 0.0001). Individuals with a high T1D-GRS had a similar rate of autoantibody positivity to that seen in individuals with type 1 diabetes diagnosed at 6-24 months of age (41% vs 58%, p = 0.2), and had markedly reduced C-peptide levels (median <3 pmol/l within 1 year of diagnosis), reflecting rapid loss of insulin secretion. These individuals also had reduced birthweights (median z score -0.89), which were lowest in those diagnosed with type 1 diabetes at <3 months of age (median z score -1.98). CONCLUSIONS/INTERPRETATION: We provide strong evidence that type 1 diabetes can present before the age of 6 months based on individuals with this extremely early-onset diabetes subtype having the classic features of childhood type 1 diabetes: high genetic risk, autoimmunity and rapid beta cell loss. The early-onset association with reduced birthweight raises the possibility that for some individuals there was reduced insulin secretion in utero. Comprehensive genetic testing for all neonatal diabetes genes remains essential for all individuals diagnosed with diabetes at <6 months of age. Graphical abstract.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Autoimunidade/imunologia , Autoimunidade/fisiologia , Biomarcadores/metabolismo , Peptídeo C/metabolismo , Feminino , Testes Genéticos , Humanos , Lactente , Recém-Nascido , Células Secretoras de Insulina/metabolismo , Masculino
5.
Diabetologia ; 62(9): 1601-1615, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31203377

RESUMO

AIMS/HYPOTHESIS: Here, we describe the characteristics of the Innovative Medicines Initiative (IMI) Diabetes Research on Patient Stratification (DIRECT) epidemiological cohorts at baseline and follow-up examinations (18, 36 and 48 months of follow-up). METHODS: From a sampling frame of 24,682 adults of European ancestry enrolled in population-based cohorts across Europe, participants at varying risk of glycaemic deterioration were identified using a risk prediction algorithm (based on age, BMI, waist circumference, use of antihypertensive medication, smoking status and parental history of type 2 diabetes) and enrolled into a prospective cohort study (n = 2127) (cohort 1, prediabetes risk). We also recruited people from clinical registries with type 2 diabetes diagnosed 6-24 months previously (n = 789) into a second cohort study (cohort 2, diabetes). Follow-up examinations took place at ~18 months (both cohorts) and at ~48 months (cohort 1) or ~36 months (cohort 2) after baseline examinations. The cohorts were studied in parallel using matched protocols across seven clinical centres in northern Europe. RESULTS: Using ADA 2011 glycaemic categories, 33% (n = 693) of cohort 1 (prediabetes risk) had normal glucose regulation and 67% (n = 1419) had impaired glucose regulation. Seventy-six per cent of participants in cohort 1 was male. Cohort 1 participants had the following characteristics (mean ± SD) at baseline: age 62 (6.2) years; BMI 27.9 (4.0) kg/m2; fasting glucose 5.7 (0.6) mmol/l; 2 h glucose 5.9 (1.6) mmol/l. At the final follow-up examination the participants' clinical characteristics were as follows: fasting glucose 6.0 (0.6) mmol/l; 2 h OGTT glucose 6.5 (2.0) mmol/l. In cohort 2 (diabetes), 66% (n = 517) were treated by lifestyle modification and 34% (n = 272) were treated with metformin plus lifestyle modification at enrolment. Fifty-eight per cent of participants in cohort 2 was male. Cohort 2 participants had the following characteristics at baseline: age 62 (8.1) years; BMI 30.5 (5.0) kg/m2; fasting glucose 7.2 (1.4) mmol/l; 2 h glucose 8.6 (2.8) mmol/l. At the final follow-up examination, the participants' clinical characteristics were as follows: fasting glucose 7.9 (2.0) mmol/l; 2 h mixed-meal tolerance test glucose 9.9 (3.4) mmol/l. CONCLUSIONS/INTERPRETATION: The IMI DIRECT cohorts are intensely characterised, with a wide-variety of metabolically relevant measures assessed prospectively. We anticipate that the cohorts, made available through managed access, will provide a powerful resource for biomarker discovery, multivariate aetiological analyses and reclassification of patients for the prevention and treatment of type 2 diabetes.


Assuntos
Biomarcadores/sangue , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Idoso , Glicemia/efeitos dos fármacos , Estudos de Coortes , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Glucose/metabolismo , Teste de Tolerância a Glucose , Humanos , Masculino , Metformina/uso terapêutico , Pessoa de Meia-Idade , Estado Pré-Diabético/sangue , Estado Pré-Diabético/epidemiologia , Estudos Prospectivos
6.
Genet Med ; 21(5): 1131-1138, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30262927

RESUMO

PURPOSE: Biomedical data governance strategies should ensure that data are collected, stored, and used ethically and lawfully. However, research participants' preferences for how data should be governed is least studied. The Diabetes Research on Patient Stratification (DIRECT) project collected substantial amounts of health and genetic information from patients at risk of, and with type II diabetes. We conducted a survey to understand participants' future data governance preferences. Results will inform the postproject data governance strategy. METHODS: A survey was distributed in Denmark, Sweden, The Netherlands, and the United Kingdom. RESULTS: In total 855 surveys were returned. Ninety-seven percent were supportive of sharing data postproject, and 90% were happy to share data with universities, and 56% with commercial companies. The top three priorities for data sharing were highly secure database, DIRECT researchers to monitor data used by other researchers, and researchers cannot identify participants. Respondents frequently suggested that a postproject Data Access Committee should involve a DIRECT researcher, diabetes clinician, patient representative, and a DIRECT participant. CONCLUSION: Preferences of how data should be governed, and what data could be shared and with whom varied between countries. Researchers are considered as key custodians of participant data. Engaging participants aids in designing governance to support their choices.


Assuntos
Pesquisa Biomédica/ética , Disseminação de Informação/métodos , Participação do Paciente/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Dinamarca , Diabetes Mellitus Tipo 2 , Ética em Pesquisa , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Pesquisadores , Inquéritos e Questionários , Suécia , Reino Unido
7.
Diabetologia ; 61(12): 2520-2527, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30229274

RESUMO

AIMS/HYPOTHESIS: Treatment change following a genetic diagnosis of MODY is frequently indicated, but little is known about the factors predicting future treatment success. We therefore conducted the first prospective study to determine the impact of a genetic diagnosis on individuals with GCK-, HNF1A- or HNF4A-MODY in the UK, and to identify clinical characteristics predicting treatment success (i.e. HbA1c ≤58 mmol/mol [≤7.5%]) with the recommended treatment at 2 years. METHODS: This was an observational, prospective, non-selective study of individuals referred to the Exeter Molecular Genetic Laboratory for genetic testing from December 2010 to December 2012. Individuals from the UK with GCK- or HNF1A/HNF4A-MODY who were not on recommended treatment at the time of genetic diagnosis, and who were diagnosed below the age of 30 years and were currently aged less than 50 years, were eligible to participate. RESULTS: A total of 44 of 58 individuals (75.9%) changed treatment following their genetic diagnosis. Eight individuals diagnosed with GCK-MODY stopped all diabetes medication without experiencing any change in HbA1c (49.5 mmol/mol [6.6%] both before the genetic diagnosis and at a median of 1.25 years' follow-up without treatment, p = 0.88). A total of 36 of 49 individuals (73.5%) diagnosed with HNF1A/HNF4A-MODY changed treatment; however, of the 21 of these individuals who were being managed with diet or sulfonylurea alone at 2 years, only 13 (36.1% of the population that changed treatment) had an HbA1c ≤58 mmol/mol (≤7.5%). These individuals had a shorter diabetes duration (median 4.6 vs 18.1 years), lower HbA1c (58 vs 73 mmol/mol [7.5% vs 8.8%]) and lower BMI (median 24.2 vs 26.0 kg/m2) at the time of genetic diagnosis, compared with individuals (n = 23/36) with an HbA1c >58 mmol/mol (>7.5%) (or <58 mmol/mol [<7.5%] on additional treatment) at the 2 year follow-up. Overall, 64% (7/11) individuals with a diabetes duration of ≤11 years and an HbA1c of ≤69 mmol/mol (≤8.5%) at time of the genetic test achieved good glycaemic control (HbA1c ≤58 mmol/mol [≤7.5%]) with diet or sulfonylurea alone at 2 years, compared with no participants with a diabetes duration of >11 years and an HbA1c of >69 mmol/mol (>8.5%) at the time of genetic diagnosis. CONCLUSIONS/INTERPRETATION: In participants with GCK-MODY, treatment cessation was universally successful, with no change in HbA1c at follow-up. In those with HNF1A/HNF4A-MODY, a shorter diabetes duration, lower HbA1c and lower BMI at genetic diagnosis predicted successful treatment with sulfonylurea/diet alone, supporting the need for early genetic diagnosis and treatment change. Our study suggests that, in individuals with HNF1A/HNF4A-MODY with a longer duration of diabetes (>11 years) at time of genetic test, rather than ceasing current treatment, a sulfonylurea should be added to existing therapy, particularly in those who are overweight or obese and have a high HbA1c.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Insulina/uso terapêutico , Metformina/uso terapêutico , Adolescente , Adulto , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Feminino , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Fator 4 Nuclear de Hepatócito/metabolismo , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Estudos Prospectivos , Adulto Jovem
8.
Environ Sci Technol ; 51(22): 13407-13416, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29043797

RESUMO

In aquatic ecosystems, the cycling and toxicity of nickel (Ni) are coupled to other elemental cycles that can limit its bioavailability. Current sediment risk assessment approaches consider acid-volatile sulfide (AVS) as the major binding phase for Ni, but have not yet incorporated ligands that are present in oxic sediments. Our study aimed to assess how metal oxides play a role in Ni bioavailability in surficial sediments exposed to effluent from two mine sites. We coupled spatially explicit sediment geochemistry (i.e., separate oxic and suboxic) to the indigenous macroinvertebrate community structure. Effluent-exposed sites contained high concentrations of sediment Ni and AVS, though roughly 80% less AVS was observed in surface sediments. Iron (Fe) oxide mineral concentrations were elevated in surface sediments and bound a substantial proportion of Ni. Redundancy analysis of the invertebrate community showed surface sediment geochemistry significantly explained shifts in community abundances. Relative abundance of the dominant mayfly (Ephemeridae) was reduced in sites with greater bioavailable Ni, but accounting for Fe oxide-bound Ni greatly decreased variation in effect thresholds between the two mine sites. Our results provide field-based evidence that solid-phase ligands in oxic sediment, most notably Fe oxides, may have a critical role in controlling nickel bioavailability.


Assuntos
Sedimentos Geológicos , Níquel , Animais , Disponibilidade Biológica , Ephemeroptera , Óxidos , Poluentes Químicos da Água
9.
Am J Ther ; 21(3): 164-73, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-22713526

RESUMO

Pasireotide is a multireceptor-targeted somatostatin analogue that has high affinity for 4 of the 5 somatostatin receptor subtypes (sst1,2,3 and sst5) and has therapeutic potential in conditions with tumors of neuroendocrine origin, such as Cushing disease, acromegaly, and neuroendocrine tumors. This phase 1, open-label, dose-escalation study assessed the overall safety and tolerability of once-daily and twice-daily pasireotide and its effects on glucose, insulin, and glucagon levels in healthy volunteers. Eleven cohorts (n = 6 for each) received subcutaneous pasireotide 150, 300, 600, 900, 1200, or 1500 µg once daily, or 150, 300, 450, 600, or 750 µg twice daily, for 8 days. Pasireotide was generally well tolerated at all doses; adverse events were predominantly mild-to-moderate gastrointestinal disorders. All participants experienced fasting and postprandial plasma glucose elevations after all doses of pasireotide; increases in blood glucose level seemed to be dose dependent. Hyperglycemia was associated with a marked suppression of insulin secretion and a mild inhibition of glucagon secretion. In conclusion, pasireotide showed good overall tolerability at doses up to 1500 µg once daily and 750 µg twice daily for 8 days. Both fasting and postprandial hyperglycemia occurred after all doses of pasireotide, which was related to the suppression of insulin secretion.


Assuntos
Glicemia/efeitos dos fármacos , Glucagon/metabolismo , Hiperglicemia/induzido quimicamente , Insulina/metabolismo , Somatostatina/análogos & derivados , Adolescente , Adulto , Relação Dose-Resposta a Droga , Esquema de Medicação , Humanos , Secreção de Insulina , Masculino , Somatostatina/administração & dosagem , Somatostatina/efeitos adversos , Somatostatina/farmacologia , Adulto Jovem
10.
Environ Toxicol Chem ; 43(7): 1524-1536, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38817108

RESUMO

Aquatic ecosystems are often impacted by a multitude of stressors, many of which are introduced by a combination of anthropogenic activities such as agricultural development, urbanization, damming, and industrial discharge. Determining the primary stressors responsible for ecological impairments at a site can be complex and challenging; however, it is crucial for making informed management decisions. Improper diagnosis of an impaired system can lead to misguided attempts at remediation, which can be both time consuming and costly. We focused on the development, implementation, and evaluation of methodologies that, in combination, allowed us to identify the primary stressors. These included a four-phase, weight-of-evidence (WOE) assessment including in situ Toxicity Identification and Evaluation (iTIE) testing, physicochemical and macrobenthos characterization, reciprocal sediment transplants, and laboratory and in situ toxicity testing. The contaminants of concern (COCs) at the site were elevated levels of ammonia, chloride, pH, and total dissolved solids in groundwater upwellings into a high-quality waterway. Reciprocal transplants of site sediments and nearby reference sediments and traditional benthic sampling showed impaired benthic indices and multiple stations around a contaminated industrial settling basin. Impaired stations had elevated COCs in groundwaters but exhibited a steep vertical concentration gradient, with concentrations decreasing near the sediment-surface water interface. We describe Phase 4 of the study, which focused on teasing out the role of dissolved oxygen sags in benthic macroinvertebrate responses. Extensive submerged and emergent macrophytes, algae, and cyanobacteria co-occurred at the impaired sites and increased throughout the summer. Laboratory testing suggested that ammonia and pH were possibly toxic at the sites, based on groundwater concentrations. The in situ toxicity testing, however, showed toxicity occurring even at stations with low levels of COCs concurrently with large diurnal fluxes in dissolved oxygen (DO). A final phase using a type of iTIE approach utilized limnocorrals with and without aeration and with in situ toxicity measures using Hyalella azteca. The Phase 4 assessment revealed that low DO levels were primarily responsible for impaired benthic communities, and COC upwellings were diluted at the sediment-water interface to nontoxic levels. These findings will allow for improved management decisions for more efficient and effective restoration activities. Environ Toxicol Chem 2024;43:1524-1536. © 2024 SETAC.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Poluentes Químicos da Água , Poluentes Químicos da Água/toxicidade , Animais , Sedimentos Geológicos/química , Testes de Toxicidade , Ecossistema
11.
J Exp Med ; 221(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38634869

RESUMO

We previously reported two siblings with inherited PD-1 deficiency who died from autoimmune pneumonitis at 3 and 11 years of age after developing other autoimmune manifestations, including type 1 diabetes (T1D). We report here two siblings, aged 10 and 11 years, with neonatal-onset T1D (diagnosed at the ages of 1 day and 7 wk), who are homozygous for a splice-site variant of CD274 (encoding PD-L1). This variant results in the exclusive expression of an alternative, loss-of-function PD-L1 protein isoform in overexpression experiments and in the patients' primary leukocytes. Surprisingly, cytometric immunophenotyping and single-cell RNA sequencing analysis on blood leukocytes showed largely normal development and transcriptional profiles across lymphoid and myeloid subsets in the PD-L1-deficient siblings, contrasting with the extensive dysregulation of both lymphoid and myeloid leukocyte compartments in PD-1 deficiency. Our findings suggest that PD-1 and PD-L1 are essential for preventing early-onset T1D but that, unlike PD-1 deficiency, PD-L1 deficiency does not lead to fatal autoimmunity with extensive leukocytic dysregulation.


Assuntos
Antígeno B7-H1 , Diabetes Mellitus Tipo 1 , Criança , Pré-Escolar , Humanos , Recém-Nascido , Autoimunidade , Antígeno B7-H1/deficiência , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Homozigoto , Receptor de Morte Celular Programada 1/deficiência , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia
12.
Altern Lab Anim ; 40(2): 109-13, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22762195

RESUMO

The British Government's proposals for the transposition of European Directive 2010/63/EU are discussed under five main headings: direct transposition without major effects on the UK legislation, introduction of stricter requirements in the Directive, retention of stricter controls in the Animals [Scientific Procedures] Act 1986, questions requiring further consideration, and matters of concern. The Home Office had published a consultation on the options in 2011, which resulted in 98 responses from organisations and 13,458 responses from individuals. Our main concerns relate to the use of non-human primates, the annual publication of the UK statistics on laboratory animal use, and the provision of greater transparency on how animals are used, and why. Finally, we conclude that the new Directive and its transposition into the national laws of the Member states provide a renewed opportunity for genuine commitment to the Three Rs, leading to progressive and significant Reduction, Refinement and Replacement.


Assuntos
Alternativas ao Uso de Animais/legislação & jurisprudência , Bem-Estar do Animal , Animais , Reino Unido
13.
Environ Toxicol Chem ; 41(1): 193-200, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34856002

RESUMO

Wilson Mine is a former vanadium mine site located in the Ouachita Mountains near Hot Springs, Arkansas. The site, which drains via two streams to Lake Catherine, has undergone extensive reclamation to significantly reduce groundwater and surface water contact with mine spoils. One of the streams passes through a former mine pit forming East Wilson Pond, and flux from pit lake sediments can result in elevated metal, that is, zinc (Zn), concentrations in overlying water. To mitigate potential risks, an investigation was conducted to evaluate the efficacy of capping materials for partitioning Zn-contaminated sediments from overlying water in East Wilson Pond. A 28-day laboratory study compared the effectiveness of capping materials including combinations of limestone, bentonite clay, and gravel for mitigating Zn flux, including under reasonable worst-case conditions (pH 5.5) encountered in the hypolimnion. Dissolved Zn was monitored over time in overlying water and in sediment porewaters within untreated controls and within the capping layer of treated systems. The use of limestone and/or bentonite clay improved buffering capacity compared to the noncapped control, and pH declined gradually but only modestly in the overlying water and porewater of all treated systems. Concentrations of Zn in overlying water of the noncapped control increased from approximately 30 to 100 µg/L during the study period, while concentrations in the overlying water and porewater of systems containing capping materials remained low (10-30 µg/L). The results demonstrated the effectiveness of the capping materials for neutralizing pH and reducing Zn flux, and a three-layer cap consisting of limestone (top) + bentonite clay (middle) + gravel (bottom) was determined to be most effective. These results were used to inform the selection of materials for the application of a cap to reduce Zn flux from the pit lake sediments. Environ Toxicol Chem 2022;41:193-200. © 2021 SETAC.


Assuntos
Lagos , Poluentes Químicos da Água , Bentonita , Carbonato de Cálcio , Argila , Sedimentos Geológicos , Água , Poluentes Químicos da Água/análise , Zinco
14.
Obes Rev ; 23(2): e13373, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34747118

RESUMO

The aim of this systematic review and meta-analysis was to examine the effectiveness of e-health interventions for the treatment of children and adolescents with overweight or obesity. Databases were searched up to November 2020. Studies were randomized controlled trials where interventions were delivered via e-health (e.g., computers, tablets, and smartphones, but not phone calls). Studies should target the treatment of overweight or obesity in children or their agent of changes and report body mass index (BMI) or BMI z-score. A meta-analysis using a random-effects model was conducted. Nineteen studies met the inclusion criteria, and 60% were of high quality. The narrative review revealed variation in behavior change strategies and modes of delivery. The pooled mean reduction in BMI or BMI z-score showed evidence for a nonzero effect (standardized mean difference = -0.31, 95% confidence interval -0.49 to -0.13), with moderately high heterogeneity between studies (I2 = 74%, p < 0.001). Subgroup analysis revealed high heterogeneity in studies with a high or unclear risk of bias. E-health interventions can be effective in treating children and adolescents with overweight and obesity and should be considered by practitioners and policymakers. However, an understanding of the most effective and acceptable intervention components, long-term benefits, and sustainability should be further studied.


Assuntos
Obesidade Infantil , Telemedicina , Adolescente , Índice de Massa Corporal , Criança , Humanos , Sobrepeso/terapia , Obesidade Infantil/terapia
15.
Altern Lab Anim ; 39(4): 403-11, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21942550

RESUMO

The 2010 Statistics of Scientific Procedures on Living Animals showed that the level of animal experimentation in Great Britain continues to rise, with just over 3.7 million procedures being conducted. This is almost exclusively due to the sustained increase in the breeding and utilisation of genetically-altered animals. Here, the general trends in the species used and the numbers and types of procedures are reviewed. In addition, the impact of the recent Government announcement to ban testing of household products on animals is discussed, along with the implications of the fish becoming the second most frequently used animal in scientific research. Finally, concerns about primate use, the REACH System, cosmetics testing and the new EU Directive on the protection of laboratory animals are explained.


Assuntos
Experimentação Animal/estatística & dados numéricos , Animais , Animais Geneticamente Modificados , Cosméticos/toxicidade , Peixes , Camundongos , Ratos , Fatores de Tempo , Reino Unido
16.
Altern Lab Anim ; 38(6): 529-32, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21275474

RESUMO

The latest report on experimental animal use in the EU indicates a slight decrease. However, the figures, which are for 2008, show that around 12 million animals are still used in laboratories throughout Europe. To date, only a summary of the data has been published, and so this report is limited to giving a comparison of trends and significant changes. The impact on the figures of the revision of Directive 86/609/EEC and the 7th Amendment to the Cosmetics Directive 76/768/EEC is discussed. In addition, consideration is given to which areas of research and regulation will need to be closely monitored, and the importance of continuing to push for the implementation of Three Rs initiatives is highlighted.


Assuntos
Alternativas ao Uso de Animais/tendências , Bem-Estar do Animal , Animais de Laboratório , Testes de Toxicidade/tendências , Alternativas aos Testes com Animais , Alternativas ao Uso de Animais/estatística & dados numéricos , Animais , Pesquisa Biomédica/métodos , União Europeia , Testes de Toxicidade/métodos , Testes de Toxicidade/estatística & dados numéricos
17.
Environ Toxicol Chem ; 39(9): 1746-1754, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32539159

RESUMO

Human-dominated waterways contain thousands of chemicals. Determining which chemical is the most important stressor is important, yet very challenging. The Toxicity Identification Evaluation (TIE) procedure from the US Environmental Protection Agency uses a series of chemical and physical manipulations to fractionate compounds within a matrix and systematically identify potential toxicants through laboratory bioassay testing. Although this may provide useful information, it lacks ecological realism because it is subject to laboratory-related artifacts and is resource intensive. The in situ Toxicity Identification Evaluation (iTIE) technology was developed to improve this approach and has undergone a number of modifications over the past several years. The novel prototype 3 consists of an array of iTIE ambient water fractionation units. Each unit is connected to a peristaltic pumping system with an organism exposure chamber that receives water from a resin chamber to chemically fractionate test site water. Test organisms included freshwater and marine standard toxicity test species. Postfractionation waters are collected for subsequent chemical analyses. Currently, the resins allow for separation of ammonia, metals, and nonpolar organics; the subsequent toxicity responses are compared between treatments and unfractionated, ambient exposures. The iTIE system was deployed to a depth of 3 m and evaluated in streams and marine harbors. Chemical analyses of water and iTIE chemical sorptive resins confirmed chemical groups causing lethal to sublethal responses. The system proved to be as sensitive or more so than the traditional phase 1 TIE test and required almost half of the resources to complete. This iTIE prototype provides a robust technology that improves stressor-causality linkages and thereby supports strong evidence for ecological risk weight-of-evidence assessments. Environ Toxicol Chem 2020;39:1746-1754. © 2020 SETAC.


Assuntos
Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Testes de Toxicidade , Amônia/análise , Animais , Bivalves/efeitos dos fármacos , Bivalves/embriologia , Análise Custo-Benefício , Embrião não Mamífero/efeitos dos fármacos , Determinação de Ponto Final , Água Doce/química , Sedimentos Geológicos/química , Humanos , Larva/efeitos dos fármacos , Rios , Ouriços-do-Mar/efeitos dos fármacos , Ouriços-do-Mar/embriologia , Poluentes Químicos da Água/toxicidade
18.
Environ Toxicol Chem ; 39(1): 240-249, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610605

RESUMO

A former mining site has been the subject of extensive remediation and restoration, with a significant focus on disconnecting mine spoils from groundwater and managing the quantity and quality of runoff. A remaining task is ensuring concentrations of zinc (Zn) in the stream outflow of a pit lake are reduced below water quality standards. The efficacy of multiple capping materials for decreasing Zn dissolution from sediments was conducted under natural and reasonable worst-case conditions (pH = 5.5). Capping materials included AquaBlok™, limestone, and limestone-bone char. Field exposures were conducted in limnocorrals that isolated overlying water columns above the sediment and capping treatments. Simultaneous in situ and ex situ toxicity tests were conducted using Daphnia magna, Hyalella azteca, and Chironomus dilutus. In situ caged organisms were protected from temperature shock (warm epilimnetic waters) by deploying within a Toxicity Assessment Container System (TACS). Organisms were exposed to surficial sediments, caps, and hypolimnetic overlying waters for 4 d. Ex situ testing was conducted in core tube mesocosms containing sediments and caps at similar temperatures (15-19 °C). Results demonstrated the usefulness of TACS deployment in stratified lake systems. There were no differences in responses between treatments involving sediment capping materials in both in situ and ex situ tests. The lack of differences was likely due to dissolved Zn in surface water being below the hardness-adjusted threshold effects levels (164 µg L-1 ). This field- and laboratory-based weight-of-evidence study provided site-specific data to support the selection of an effective remedy, with reduced uncertainty compared to laboratory and chemistry-only approaches. Environ Toxicol Chem 2019;39:240-249. © 2019 SETAC.


Assuntos
Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos , Sedimentos Geológicos/química , Rios/química , Poluentes Químicos da Água/toxicidade , Zinco/toxicidade , Anfípodes/efeitos dos fármacos , Anfípodes/metabolismo , Animais , Disponibilidade Biológica , Chironomidae/efeitos dos fármacos , Chironomidae/metabolismo , Daphnia/efeitos dos fármacos , Daphnia/metabolismo , Lagos/química , Mineração , Testes de Toxicidade , Poluentes Químicos da Água/análise , Zinco/análise
19.
BMJ Open ; 10(3): e034716, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32193268

RESUMO

OBJECTIVES: To evaluate and compare the lifetime costs associated with strategies to identify individuals with monogenic diabetes and change their treatment to more appropriate therapy. DESIGN: A decision analytical model from the perspective of the National Health Service (NHS) in England and Wales was developed and analysed. The model was informed by the literature, routinely collected data and a clinical study conducted in parallel with the modelling. SETTING: Secondary care in the UK. PARTICIPANTS: Simulations based on characteristics of patients diagnosed with diabetes <30 years old. INTERVENTIONS: Four test-treatment strategies to identify individuals with monogenic diabetes in a prevalent cohort of diabetics diagnosed under the age of 30 years were modelled: clinician-based genetic test referral, targeted genetic testing based on clinical prediction models, targeted genetic testing based on biomarkers, and blanket genetic testing. The results of the test-treatment strategies were compared with a strategy of no genetic testing. PRIMARY AND SECONDARY OUTCOME MEASURES: Discounted lifetime costs, proportion of cases of monogenic diabetes identified. RESULTS: Based on current evidence, strategies using clinical characteristics or biomarkers were estimated to save approximately £100-£200 per person with diabetes over a lifetime compared with no testing. Sensitivity analyses indicated that the prevalence of monogenic diabetes, the uptake of testing, and the frequency of home blood glucose monitoring had the largest impact on the results (ranging from savings of £400-£50 per person), but did not change the overall findings. The model is limited by many model inputs being based on very few individuals, and some long-term data informed by clinical opinion. CONCLUSIONS: Costs to the NHS could be saved with targeted genetic testing based on clinical characteristics or biomarkers. More research should focus on the economic case for the use of such strategies closer to the time of diabetes diagnosis. TRIAL REGISTRATION NUMBER: NCT01238380.


Assuntos
Diabetes Mellitus , Atenção Secundária à Saúde/economia , Adulto , Glicemia , Automonitorização da Glicemia , Análise Custo-Benefício , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/genética , Inglaterra/epidemiologia , Humanos , Medicina Estatal , País de Gales/epidemiologia
20.
Altern Lab Anim ; 37 Suppl 2: 83-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20105018

RESUMO

Until I began working at FRAME, I was not really aware of the Three Rs or FRAME's work to promote and progress them. It soon became clear to me that it made scientific sense and that it could make a difference to many thousands of laboratory animals. As an alternatives advocate, I regularly experience optimism, frustration and determination. This is illustrated most clearly by the primate research dilemma. Here, I describe the positive and negative experiences I have had whilst working toward the goal of replacing primate experiments, and how these have led me to undertake a multidisciplinary PhD project on primate use in biomedical research. The aim is to examine how research scientists view the opportunities and challenges involved in the use of primates in biomedical science, and to investigate the feasibility of phasing out their use. As a result of the research, I hope to provide a new perspective, to depolarise the debate and bring about a constructive dialogue between all parties as to how and when primate research could be replaced.


Assuntos
Alternativas aos Testes com Animais/ética , Bem-Estar do Animal/ética , Animais de Laboratório , Ciência dos Animais de Laboratório/ética , Primatas , Projetos de Pesquisa , Animais , Modelos Animais
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