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1.
Rev Sci Instrum ; 94(4)2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38081276

RESUMEN

A new shattered pellet injection system was designed and built to perform disruption mitigation experiments on ASDEX Upgrade. The system can inject pellets with diameters of 1, 2, 4, or 8 mm with variable lengths over a range of L/D ratios of ∼0.5-1.5. By using helium or deuterium as propellant gas, the pellets can be accelerated to speeds between 60 and 750 m/s. The velocity range slightly depends on the pellet mass. The injection system is capable of preparing three pellets in separate barrels at the same time. Once accelerated by the propellant gas pulse, the pellets travel through one of three parallel flight tubes. Each flight tube is separated into three sections with increasing diameters of 12, 14, and 16 mm. Two gaps between the sections allow for removal of the propellant gas by expansion into two separate expansions tanks (0.3 and 0.035 m3), pellet observation in the first gap and the torus gate valve in the second. Each flight tube end is equipped with an exchangeable shatter head with different shatter angles, square or circular cross-section, and different lengths. The gas preparation and control systems allow highly automated pellet generation for precision of the pellet composition and an excellent reproducibility of shattered pellet experiments.

2.
J Environ Manage ; 330: 117140, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36603252

RESUMEN

Natural resource governance is inherently complex owing to the socio-ecological systems in which it is embedded. Working arrangements have been fundamentally transformed throughout the COVID-19 pandemic with potential negative impacts on trust-based social networks foundational to resource management and transboundary governance. To inform development of a post-pandemic new-normal in resource management, we examined trust relationships using the Laurentian Great Lakes of North America as a case study. 82.9% (n = 97/117) of Great Lakes fishery managers and scientists surveyed indicated that virtual engagement was effective for maintaining well-established relationships during the pandemic; however, 76.7% (n = 89/116) of respondents indicated in-person engagement to be more effective than virtual engagement for building and maintaining trust. Despite some shortcomings, virtual or remote engagement presents opportunities, such as: (1) care and nurturing of well-established long-term relationships; (2) short-term (1-3 years) trust maintenance; (3) peer-peer or mentor-mentee coordination; (4) supplemental communications; (5) producer-push knowledge dissemination; and, if done thoughtfully, (6) enhancing diversity, equity, and inclusion. Without change, pre-pandemic trust-based relationships foundational to cooperative, multinational, resource management are under threat.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , Confianza , Recursos Naturales , Conservación de los Recursos Naturales
3.
Mol Genet Metab ; 132(4): 234-243, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33642210

RESUMEN

BACKGROUND: Recent years have witnessed a considerable increase in clinical trials of new investigational agents for Fabry disease (FD). Several trials investigating different agents are currently in progress; however, lack of standardisation results in challenges to interpretation and comparison. To facilitate the standardisation of investigational programs, we have developed a common framework for future clinical trials in FD. METHODS AND FINDINGS: A broad consensus regarding clinical outcomes and ways to measure them was obtained via the Delphi methodology. 35 FD clinical experts from 4 continents, representing 3389 FD patients, participated in 3 rounds of Delphi procedure. The aim was to reach a consensus regarding clinical trial design, best treatment comparator, clinical outcomes, measurement of those clinical outcomes and inclusion and exclusion criteria. Consensus results of this initiative included: the selection of the adaptative clinical trial as the ideal study design and agalsidase beta as ideal comparator treatment due to its longstanding use in FD. Renal and cardiac outcomes, such as glomerular filtration rate, proteinuria and left ventricular mass index, were prioritised, whereas neurological outcomes including cerebrovascular and white matter lesions were dismissed as a primary or secondary outcome measure. Besides, there was a consensus regarding the importance of patient-related outcomes such as general quality of life, pain, and gastrointestinal symptoms. Also, unity about lysoGb3 and Gb3 tissue deposits as useful surrogate markers of the disease was obtained. The group recognised that cardiac T1 mapping still has potential but requires further development before its widespread introduction in clinical trials. Finally, patients with end-stage renal disease or renal transplant should be excluded unless a particular group for them is created inside the clinical trial. CONCLUSION: This consensus will help to shape the future of clinical trials in FD. We note that the FDA has, coincidentally, recently published draft guidelines on clinical trials in FD and welcome this contribution.


Asunto(s)
Ensayos Clínicos como Asunto , Terapia de Reemplazo Enzimático , Enfermedad de Fabry/tratamiento farmacológico , Riñón/metabolismo , Adulto , Consenso , Técnica Delphi , Enfermedad de Fabry/genética , Enfermedad de Fabry/metabolismo , Enfermedad de Fabry/patología , Femenino , Globósidos/uso terapéutico , Glucolípidos/uso terapéutico , Humanos , Isoenzimas/genética , Riñón/efectos de los fármacos , Riñón/patología , Masculino , Persona de Mediana Edad , Calidad de Vida , Esfingolípidos/uso terapéutico , Resultado del Tratamiento , Trihexosilceramidas/uso terapéutico , alfa-Galactosidasa/genética
4.
Br J Surg ; 108(4): 441-447, 2021 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-33615351

RESUMEN

BACKGROUND: Complicated intra-abdominal infections (cIAIs) are associated with significant morbidity and mortality. The aim of this study was to describe the clinical characteristics of patients with cIAI in a multicentre study and to develop clinical prediction models (CPMs) to help identify patients at risk of mortality or relapse. METHODS: A multicentre observational study was conducted from August 2016 to February 2017 in the UK. Adult patients diagnosed with cIAI were included. Multivariable logistic regression was performed to develop CPMs for mortality and cIAI relapse. The c-statistic was used to test model discrimination. Model calibration was tested using calibration slopes and calibration in the large (CITL). The CPMs were then presented as point scoring systems and validated further. RESULTS: Overall, 417 patients from 31 surgical centres were included in the analysis. At 90 days after diagnosis, 17.3 per cent had a cIAI relapse and the mortality rate was 11.3 per cent. Predictors in the mortality model were age, cIAI aetiology, presence of a perforated viscus and source control procedure. Predictors of cIAI relapse included the presence of collections, outcome of initial management, and duration of antibiotic treatment. The c-statistic adjusted for model optimism was 0.79 (95 per cent c.i. 0.75 to 0.87) and 0.74 (0.73 to 0.85) for mortality and cIAI relapse CPMs. Adjusted calibration slopes were 0.88 (95 per cent c.i. 0.76 to 0.90) for the mortality model and 0.91 (0.88 to 0.94) for the relapse model; CITL was -0.19 (95 per cent c.i. -0.39 to -0.12) and - 0.01 (- 0.17 to -0.03) respectively. CONCLUSION: Relapse of infection and death after complicated intra-abdominal infections are common. Clinical prediction models were developed to identify patients at increased risk of relapse or death after treatment, these now require external validation.


Asunto(s)
Reglas de Decisión Clínica , Infecciones Intraabdominales/etiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Femenino , Humanos , Infecciones Intraabdominales/diagnóstico , Infecciones Intraabdominales/tratamiento farmacológico , Infecciones Intraabdominales/mortalidad , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Recurrencia , Factores de Riesgo
5.
Lupus ; 27(10): 1687-1696, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30041577

RESUMEN

The relationship between serum concentration of complement C4 ([C4]) and C4 gene copy number (GCN) was investigated in 56 systemic lupus erythematosus (SLE) patients and 33 age and sex-matched controls in a Western Australian population. C4A and C4B gene copy numbers (C4A & B GCN) together with the presence or absence of the ≈6.4-kb human endogenous retroviral element type K (hereafter HERV-K) in intron 9 were estimated by two TaqMan™ real-time PCR (RT-PCR) assays that measured total C4 and HERV-K GCNs, respectively. There was good correlation between the two methods; however, the HERV-K GCN method showed a positive bias (≈6%) relative to the C4A & B total GCN. Despite individual variation, excellent correlation between total C4 GCN and mean [C4] per GCN was observed for both the SLE and control cohorts ( R2 = 88% and R2 = 99%, respectively). It was noted that serum [C4] was significantly lower in the SLE patients than the controls ( p = 0.006) despite there being no difference between C4A and C4B GCN in both cohorts. The data therefore confirm previous reports that the C4A genes are preferentially associated with the presence of the HERV-K insertion relative to C4B genes and does not support the hypothesis that low [C4] in SLE is explained by low C4A GCNs. There was no evidence also that the presence of the HERV-K insertion in C4 genes influenced [C4]. This study supports the view that low [C4] in SLE patients is due to consumption rather than deficient synthesis related to lower C4A & B GCN.


Asunto(s)
Complemento C4a/genética , Complemento C4b/genética , Dosificación de Gen , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/genética , Adulto , Biomarcadores/sangre , Estudios de Casos y Controles , Elementos Transponibles de ADN , ADN Viral/genética , Regulación hacia Abajo , Retrovirus Endógenos/genética , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Lupus Eritematoso Sistémico/diagnóstico , Masculino , Persona de Mediana Edad , Fenotipo , Factores de Riesgo , Australia Occidental
7.
J Dent Res ; 96(5): 578-585, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28068493

RESUMEN

Mutations in bone morphogenetic protein 1 (BMP1) in humans or deletion of BMP1 and related protease tolloid like 1 (TLL1) in mice lead to osteogenesis imperfecta (OI). Here, we show progressive periodontal defects in mice in which both BMP1 and TLL1 have been conditionally ablated, including malformed periodontal ligament (PDL) (recently shown to play key roles in normal alveolar bone formation), significant loss in alveolar bone mass ( P < 0.01), and a sharp reduction in cellular cementum. Molecular mechanism studies revealed a dramatic increase in the uncleaved precursor of type I collagen (procollagen I) and a reduction in dentin matrix protein 1 (DMP1), which is partially responsible for defects in extracellular matrix (ECM) formation and mineralization. We also showed a marked increase in the expression of matrix metallopeptidase 13 (MMP13) and tartrate-resistant acid phosphatase (TRAP), leading to an acceleration in periodontal breakdown. Finally, we demonstrated that systemic application of antibiotics significantly improved the alveolar bone and PDL damage of the knockdown phenotype, which are thus shown to be partially secondary to pathogen-induced inflammation. Together, identification of the novel roles of BMP1 and TLL1 in maintaining homeostasis of periodontal formation, partly via biosynthetic processing of procollagen I and DMP1, provides novel insights into key contributions of the extracellular matrix environment to periodontal homeostasis and contributes toward understanding of the pathology of periodontitis.


Asunto(s)
Proteína Morfogenética Ósea 1/fisiología , Matriz Extracelular/metabolismo , Ligamento Periodontal/fisiología , Periodontitis/fisiopatología , Metaloproteinasas Similares a Tolloid/fisiología , Animales , Antibacterianos/farmacología , Proteína Morfogenética Ósea 1/deficiencia , Proteínas de la Matriz Extracelular/biosíntesis , Homeostasis , Inmunohistoquímica , Mandíbula , Metaloproteinasa 13 de la Matriz/metabolismo , Ratones , Ratones Noqueados , Microscopía Confocal , Fenotipo , Procolágeno/biosíntesis , Fosfatasa Ácida Tartratorresistente/metabolismo , Metaloproteinasas Similares a Tolloid/deficiencia , Microtomografía por Rayos X
8.
Allergy ; 71(9): 1256-63, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27240281

RESUMEN

The prevalence of allergic conditions has continuously increased in the last few decades in Westernized countries. A dysbiotic gut microbiome may play an important role in the development of allergic diseases. Genetic, environmental, and dietary factors may alter the commensal microbiota leading to inflammatory dysregulation of homeostasis. Murine and human studies have begun to elucidate the role of the microbiota in the pathogenesis of atopic diseases including asthma, atopic dermatitis, and food allergies. However, the role of the microbiome in most eosinophilic gastrointestinal diseases (EGIDs) is not yet known. This review provides an overview of what is currently known about the development of tolerance from both molecular and clinical standpoints. We also look at the gut-specific microbiome and its role in atopic conditions with the hope of applying this knowledge to the understanding, prevention, and treatment of EGIDs, particularly EoE.


Asunto(s)
Tracto Gastrointestinal/inmunología , Tracto Gastrointestinal/microbiología , Hipersensibilidad Inmediata/etiología , Microbiota , Factores de Edad , Animales , Exposición a Riesgos Ambientales/efectos adversos , Esofagitis Eosinofílica/diagnóstico , Esofagitis Eosinofílica/etiología , Esofagitis Eosinofílica/metabolismo , Esofagitis Eosinofílica/terapia , Tracto Gastrointestinal/metabolismo , Humanos , Hipersensibilidad Inmediata/diagnóstico , Hipersensibilidad Inmediata/metabolismo , Hipersensibilidad Inmediata/terapia , Especificidad de Órganos/inmunología
9.
Bone Joint Res ; 5(2): 61-5, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26883967

RESUMEN

OBJECTIVES: Temperature is known to influence muscle physiology, with the velocity of shortening, relaxation and propagation all increasing with temperature. Scant data are available, however, regarding thermal influences on energy required to induce muscle damage. METHODS: Gastrocnemius and soleus muscles were harvested from 36 male rat limbs and exposed to increasing impact energy in a mechanical test rig. Muscle temperature was varied in 5°C increments, from 17°C to 42°C (to encompass the in vivo range). The energy causing non-recoverable deformation was recorded for each temperature. A measure of tissue elasticity was determined via accelerometer data, smoothed by low-pass fifth order Butterworth filter (10 kHz). Data were analysed using one-way analysis of variance (ANOVA) and significance was accepted at p = 0.05. RESULTS: The energy required to induce muscle failure was significantly lower at muscle temperatures of 17°C to 32°C compared with muscle at core temperature, i.e., 37°C (p < 0.01). During low-energy impacts there were no differences in muscle elasticity between cold and warm muscles (p = 0.18). Differences in elasticity were, however, seen at higher impact energies (p < 0.02). CONCLUSION: Our findings are of particular clinical relevance, as when muscle temperature drops below 32°C, less energy is required to cause muscle tears. Muscle temperatures of 32°C are reported in ambient conditions, suggesting that it would be beneficial, particularly in colder environments, to ensure that peripheral muscle temperature is raised close to core levels prior to high-velocity exercise. Thus, this work stresses the importance of not only ensuring that the muscle groups are well stretched, but also that all muscle groups are warmed to core temperature in pre-exercise routines.Cite this article: Professor A. H. R. W. Simpson. Increased risk of muscle tears below physiological temperature ranges. Bone Joint Res 2016;5:61-65. doi: 10.1302/2046-3758.52.2000484.

11.
J Inherit Metab Dis ; 38(3): 495-503, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25112389

RESUMEN

Pompe disease is a rare, progressive lysosomal storage disorder for which enzyme therapy (ERT) became available in 2006. Four years earlier, the IPA/Erasmus MC survey, an international longitudinal prospective survey, was established to collect information on the natural course of the disease and its burden on patients. The survey is a collaboration between Erasmus MC University Medical Center and the International Pompe Association (IPA) and comprises an annual questionnaire that was specifically designed to assess the symptoms and problems of the disease. Here we review our results of over 10 years of follow-up, and discuss the survey's contribution to the field. Tracking 408 Pompe patients between 2002 and 2013, the cumulative data reveals the broad range of clinical manifestations that interfere with patients' lives. The survey allowed us to quantify the rate of disease progression and the positive effects of ERT on patients' quality of life, fatigue, and participation in daily life. Furthermore, it showed for the first time that survival is reduced in adult Pompe disease and improved by ERT. Our results show that a patient survey can serve as a valuable and reliable tool for obtaining quantifiable information on the natural course of a rare disease and on the effects of therapy in a large cohort over a very long time. Most importantly, by working with patient reported outcomes, the survey provides the data that is truly relevant to the patient and complementary to clinical datasets.


Asunto(s)
Terapia de Reemplazo Enzimático/métodos , Enfermedad del Almacenamiento de Glucógeno Tipo II/tratamiento farmacológico , Evaluación del Resultado de la Atención al Paciente , Participación del Paciente , alfa-Glucosidasas/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Estudios de Cohortes , Fatiga , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Calidad de Vida , Autoinforme , Adulto Joven
12.
Contraception ; 90(4): 447-53, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24929889

RESUMEN

OBJECTIVES: In Scotland most women get emergency contraception (EC) from pharmacies. Pharmacists currently cannot provide effective ongoing contraception after EC. In this pilot study, we aimed to determine the feasibility of a larger study designed to ascertain if pharmacy-based interventions can increase the uptake of effective contraception after EC. STUDY DESIGN: This is a pilot study of women presenting for levonorgestrel EC to community pharmacies in Edinburgh, UK, in 2012. Pharmacies were cluster randomized to provide either standard care or one of two interventions: (a) one packet of progestogen-only pills (POPs), giving women 1 month to arrange ongoing contraception; (b) invitation to present the empty EC packet to a family planning clinic (FPC) for contraceptive advice (rapid access). RESULTS: One hundred sixty-eight women were recruited from 11 pharmacies to POP (n=56), rapid access (n=58) and standard care (N=54) groups, respectively. Telephone follow-up was conducted successfully in 102 women (61%) 6-8 weeks later to determine current contraceptive use. In the POP arm, 35/39 (90%) women used the pills provided, and 9/28 women (32%) in the rapid access arm attended the FPC. The proportion of women using effective contraception at follow-up was significantly greater in both POP [56% (22/39), p=<0.001] and rapid access [52% (13/25), p=0.006] groups compared to standard care [16% (5/31)]. The relative probability of a woman using an effective method of contraception versus barrier/no method, after use of EC, was 3.13 [95% confidence interval (CI), 1.90-5.13] in the POP group and 2.57 (95% CI, 1.55-4.27) in the rapid access group. CONCLUSIONS: This promising pilot study suggests that simple pharmacy-based interventions may increase the uptake of effective contraception after EC. A larger study is required to provide further validation of these findings. IMPLICATIONS STATEMENT: For women obtaining EC from a pharmacy, simple interventions such as supplying 1 month of a POP, or offering rapid access to a FPC, hold promise as strategies to increase the uptake of effective contraception after EC.


Asunto(s)
Conducta Anticonceptiva/estadística & datos numéricos , Anticoncepción Postcoital , Anticonceptivos Hormonales Orales/uso terapéutico , Servicios de Planificación Familiar/estadística & datos numéricos , Aceptación de la Atención de Salud/estadística & datos numéricos , Farmacias , Progestinas/uso terapéutico , Adolescente , Adulto , Anticonceptivos Poscoito , Consejo Dirigido , Femenino , Humanos , Levonorgestrel , Proyectos Piloto , Escocia , Adulto Joven
13.
Clin Pharmacol Ther ; 95(2): 141-6, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24096968

RESUMEN

Pegylated interferon-α (PEG-IFN-α or PEG-IFN 2a and 2b)- and ribavirin (RBV)-based regimens are the mainstay for treatment of hepatitis C virus (HCV) genotype 1. IFNL3 (IL28B) genotype is the strongest baseline predictor of response to PEG-IFN-α and RBV therapy in previously untreated patients and can be used by patients and clinicians as part of the shared decision-making process for initiating treatment for HCV infection. We provide information regarding the clinical use of PEG-IFN-α- and RBV-containing regimens based on IFNL3 genotype.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Interleucinas/genética , Polietilenglicoles/uso terapéutico , Antivirales/administración & dosificación , Quimioterapia Combinada , Pruebas Genéticas/normas , Genotipo , Humanos , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Interferones , Polietilenglicoles/administración & dosificación , Polimorfismo de Nucleótido Simple/genética , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/uso terapéutico , Ribavirina/administración & dosificación , Ribavirina/uso terapéutico , Resultado del Tratamiento
14.
Mol Ecol ; 23(3): 561-74, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24330274

RESUMEN

Both environmental and genetic influences can result in phenotypic variation. Quantifying the relative contributions of local adaptation and phenotypic plasticity to phenotypes is key to understanding the effect of environmental variation on populations. Identifying the selective pressures that drive divergence is an important, but often lacking, next step. High gene flow between high- and low-altitude common frog (Rana temporaria) breeding sites has previously been demonstrated in Scotland. The aim of this study was to assess whether local adaptation occurs in the face of high gene flow and to identify potential environmental selection pressures that drive adaptation. Phenotypic variation in larval traits was quantified in R. temporaria from paired high- and low-altitude sites using three common temperature treatments. Local adaptation was assessed using Q(ST)-F(ST) analyses, and quantitative phenotypic divergence was related to environmental parameters using Mantel tests. Although evidence of local adaptation was found for all traits measured, only variation in larval period and growth rate was consistent with adaptation to altitude. Moreover, this was only evident in the three mountains with the highest high-altitude sites. This variation was correlated with mean summer and winter temperatures, suggesting that temperature parameters are potentially strong selective pressures maintaining local adaptation, despite high gene flow.


Asunto(s)
Adaptación Fisiológica/genética , Altitud , Flujo Génico , Rana temporaria/genética , Temperatura , Animales , Genética de Población , Modelos Genéticos , Fenotipo , Carácter Cuantitativo Heredable , Escocia , Selección Genética
15.
J Hand Surg Eur Vol ; 39(6): 637-41, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23735809

RESUMEN

The UK National Patient Safety Agency issued a rapid response report in 2009 following reports of complications related to digital tourniquet use and inadvertent retention. In their guidance, they recommend the use of CE marked digital tourniquets and advise against the use of surgical gloves. There are a number of different commercially available non-pneumatic digital tourniquets, but little clear data relating to their comparable physical properties, clinical efficacy or safety. The aim of this study was to investigate the variability of pressures exerted by non-pneumatic digital tourniquets. A Tekscan FlexiForce(®) force sensor was used to measure applied force and to calculate the surface pressures under: the Toe-niquet™; T-Ring™ and surgical glove 'roll down' tourniquets in finger models. The lowest mean pressures were produced by the larger glove sizes (size 8) (25 mmHg), while the highest pressures were produced by the Toe-niquet (1560 mmHg). There was a significant overall difference in pressures exerted under tourniquets when comparing tourniquet type (p<0.001) and finger size (p<0.001) with these techniques. It is difficult to anticipate and regulate pressures generated by non-pneumatic tourniquets. Safe limits for application time and surface pressures are difficult to define. Further work is required to model the pressure effects of commercially available digital tourniquets and to identify which are most effective but safe.


Asunto(s)
Dedos/cirugía , Dedos del Pie/cirugía , Torniquetes , Guantes Quirúrgicos , Humanos , Modelos Anatómicos , Presión
16.
J Viral Hepat ; 20(12): 858-66, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24304455

RESUMEN

Anaemia frequently complicates peginterferon/ribavirin therapy for chronic hepatitis C infection. Better prediction of anaemia, ribavirin dose reduction or erythropoietin (EPO) need, may enhance patient management. Inosine triphosphatase (ITPA) genetic variants are associated with ribavirin-induced anaemia and dose reduction; however, their impact in real-life clinic patient cohorts remains to be defined. We studied 193 clinic patients with chronic hepatitis C infection of mixed viral genotype (genotype 1/4 n = 123, genotype 2/3, n = 70) treated with peginterferon/ribavirin. Patients were genotyped for ITPA polymorphisms rs1127354 and rs7270101 using Taqman primers. Hardy-Weinberg equilibrium was present. Estimated ITPA deficiency was graded on severity (0-3, no deficiency/mild/moderate/severe, n = 126/40/24/3, respectively). Multivariable models tested the association with anaemia at 4 weeks of treatment [including decline in haemoglobin (g/dL); haemoglobin <10 g/dL and haemoglobin decline >3 g/dL]; ribavirin dose reduction and EPO use and explored sustained viral response (SVR) to peginterferon/ribavirin. More severe ITPA deficiency was associated with less reduction in haemoglobin level (P <0.001; R(2) = 0.34), less ribavirin dose reduction (OR 0.42; (95% CI = 0.23-0.77); P = 0.005) and less EPO use [OR 0.53; (0.30-0.94); P = 0.029]. ITPA deficiency was associated with SVR [OR: 1.70; (1.02-2.83); P = 0.041] independently of clinical covariates (adjusted R(2) = 0.31). In this clinical cohort, ITPA deficiency helped predict the risk of on-treatment anaemia, ribavirin dose reduction, need for EPO support and was associated with SVR. For patients on HCV regimens including peginterferon/ribavirin, testing for ITPA deficiency may have clinical utility.


Asunto(s)
Anemia/inducido químicamente , Anemia/epidemiología , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Errores Innatos del Metabolismo/diagnóstico , Pirofosfatasas/deficiencia , Ribavirina/efectos adversos , Anciano , Quimioterapia Combinada/efectos adversos , Quimioterapia Combinada/métodos , Femenino , Humanos , Interferones/uso terapéutico , Masculino , Persona de Mediana Edad , Ribavirina/uso terapéutico , Resultado del Tratamiento
17.
J Viral Hepat ; 20(11): 745-60, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24168254

RESUMEN

Emerging data indicate that all-oral antiviral treatments for chronic hepatitis C virus (HCV) will become a reality in the near future. In replacing interferon-based therapies, all-oral regimens are expected to be more tolerable, more effective, shorter in duration and simpler to administer. Coinciding with new treatment options are novel methodologies for disease screening and staging, which create the possibility of more timely care and treatment. Assessments of histologic damage typically are performed using liver biopsy, yet noninvasive assessments of histologic damage have become the norm in some European countries and are becoming more widespread in the United States. Also in place are new Centers for Disease Control and Prevention (CDC) initiatives to simplify testing, improve provider and patient awareness and expand recommendations for HCV screening beyond risk-based strategies. Issued in 2012, the CDC recommendations aim to increase HCV testing among those with the greatest HCV burden in the United States by recommending one-time testing for all persons born during 1945-1965. In 2013, the United States Preventive Services Task Force adopted similar recommendations for risk-based and birth-cohort-based testing. Taken together, the developments in screening, diagnosis and treatment will likely increase demand for therapy and stimulate a shift in delivery of care related to chronic HCV, with increased involvement of primary care and infectious disease specialists. Yet even in this new era of therapy, barriers to curing patients of HCV will exist. Overcoming such barriers will require novel, integrative strategies and investment of resources at local, regional and national levels.


Asunto(s)
Antivirales/administración & dosificación , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/tratamiento farmacológico , Tamizaje Masivo/métodos , Guías de Práctica Clínica como Asunto , Administración Oral , Centers for Disease Control and Prevention, U.S. , Hepatitis C Crónica/prevención & control , Humanos , Hígado/patología , Estados Unidos
18.
Mol Ecol ; 22(14): 3737-51, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23692266

RESUMEN

Recent and historical species' associations with climate can be inferred using molecular markers. This knowledge of population and species-level responses to climatic variables can then be used to predict the potential consequences of ongoing climate change. The aim of this study was to predict responses of Rana temporaria to environmental change in Scotland by inferring historical and contemporary patterns of gene flow in relation to current variation in local thermal conditions. We first inferred colonization patterns within Europe following the last glacial maximum by combining new and previously published mitochondrial DNA sequences. We found that sequences from our Scottish samples were identical to (92%), or clustered with, the common haplotype previously identified from Western Europe. This clade showed very low mitochondrial variation, which did not allow inference of historical colonization routes but did allow interpretation of patterns of current fine-scale population structure without consideration of confounding historical variation. Second, we assessed fine-scale microsatellite-based patterns of genetic variation in relation to current altitudinal temperature gradients. No population structure was found within altitudinal gradients (average FST=0.02), despite a mean annual temperature difference of 4.5 °C between low- and high-altitude sites. Levels of genetic diversity were considerable and did not vary between sites. The panmictic population structure observed, even along temperature gradients, is a potentially positive sign for R. temporaria persistence in Scotland in the face of a changing climate. This study demonstrates that within taxonomic groups, thought to be at high risk from environmental change, levels of vulnerability can vary, even within species.


Asunto(s)
ADN Mitocondrial/genética , Rana temporaria/genética , Rana temporaria/fisiología , Animales , Clima , Cambio Climático , Variación Genética , Genética de Población , Haplotipos , Repeticiones de Microsatélite , Datos de Secuencia Molecular , Escocia
19.
J Fish Biol ; 82(2): 600-17, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23398071

RESUMEN

Two previously described lacustrine cisco Coregonus spp. morphs [i.e. a small (<300 mm fork length, L(F)), low-gillraker (≤44) morph and a large (≥300 mm L(F) ), high-gillraker (≥45) morph] from Great Slave Lake, NT, Canada, were found to be synonymous with cisco Coregonus artedi. Geometric body shape did not differ between the two size classes nor could they be differentiated by 24 size-corrected linear measurements, indicating that the two groups had similar phenotypes. Strong, positive correlations between all linear characters and geometric centroid size (a composite variable of fish body length, mass and age) suggested that body morphology changed with age as fish grew. Total gillraker number (N(GR)) increased with L(F) according to: N(GR) = 36.3 + 0.034L(F). Differences in gillraker number and phenotype with age and size were explained by shifts in habitat and trophic resource use. Relative abundance within 0-30, 30-60, 60-90 and >90 m depth strata differed between size classes suggesting that morphology changed when fish shifted their habitat as they grew older. Large C. artedi had lower δ(13)C and slightly higher δ(15)N, indicating greater reliance on pelagic prey resources (i.e. more or larger zooplankton, such as Mysis spp.), compared to small C. artedi, which relied slightly more on benthic prey. Gillraker shape and number have always been used as key diagnostic characters in coregonine taxonomy; based on the findings presented here, ontogenetic shifts should be accounted for in resulting classifications.


Asunto(s)
Dieta/veterinaria , Ecosistema , Salmonidae/anatomía & histología , Salmonidae/fisiología , Factores de Edad , Animales , Tamaño Corporal , Cadena Alimentaria , Fenotipo , Densidad de Población , Salmonidae/crecimiento & desarrollo
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