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1.
Radiat Res ; 200(4): 340-348, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37590489

RESUMEN

The Rössing Uranium Limited (RUL) open-cast uranium mine in Namibia has operated since 1976. Studies of underground uranium miners from Europe and North America have shown increased cancer risks (principally lung cancer). We explored the association between radiation doses and selected cancers in RUL mineworkers. Employees with at least one-year of continuous employment between 1976 and 2010 were included. Incident cancer cases [lung, extra-thoracic airways (ETA), leukemia, brain and kidney] occurring before the end of 2015 were identified from the Namibian and South African National Cancer Registries, and RUL's occupational health provider. Using a case-cohort design, data on exposure and confounding factors were collected for all cancer cases among the study cohort and a stratified random sample (sub-cohort) of the cohort, including cases. Radiation doses were estimated based on annual dose records held by RUL. In total, 76 cancer cases (32 lung, 18 ETA, 8 leukemia, 9 brain, 9 kidney) and a sub-cohort of 1,121 sampled from 7,901 RUL employees were included. A weighted Cox model, adjusted for available known confounders, produced a rate ratio (95% CI) for lung cancer of 1.42 (0.42, 4.77) and 1.22 (0.26, 5.68), respectively, for medium and higher cumulative lung dose categories compared to the lower category, and 1.04 (0.95, 1.13) for a dose increase of 10 mSv. This study faced considerable challenges with respect to case ascertainment, exposure estimates, and ensuring accuracy of key variables. Persuasive consistent evidence for elevated cancer risk was not found for radiation or other exposures studied at the Rössing uranium mine.

2.
J Hematol Oncol ; 16(1): 56, 2023 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-37237311

RESUMEN

Haemophagocytic lymphohistiocytosis (HLH) is a lethal syndrome of excessive immune activation. We undertook a nationwide study in England of all cases of HLH diagnosed between 2003 and 2018, using linked electronic health data from hospital admissions and death certification. We modelled interactions between demographics and comorbidities and estimated one-year survival by calendar year, age group, gender and comorbidity (haematological malignancy, auto-immune, other malignancy) using Cox regression. There were 1628 people with HLH identified. Overall, crude one-year survival was 50% (95% Confidence interval 48-53%) which varied substantially with age (0-4: 61%; 5-14: 76%; 15-54: 61%; > 55: 24% p < 0.01), sex (males, 46%, worse than females, 55% p < 0.01) and associated comorbidity (auto-immune, 69%, haematological malignancy 28%, any other malignancy, 37% p < 0.01). Those aged < 54 years had a threefold increased risk of death at 1-year amongst HLH associated with malignancy compared to auto-immune. However, predicted 1-year survival decreased markedly with age in those with auto-immune (age 0-14, 84%; 15-54, 73%; > 55, 27%) such that among those > 55 years, survival was as poor as for patients with haematological malignancy. One-year survival following a diagnosis of HLH varies considerably by age, gender and associated comorbidity. Survival was better in those with auto-immune diseases among the young and middle age groups compared to those with an underlying malignancy, whereas in older age groups survival was uniformly poor regardless of the underlying disease process.


Asunto(s)
Neoplasias Hematológicas , Linfohistiocitosis Hemofagocítica , Neoplasias , Masculino , Persona de Mediana Edad , Femenino , Humanos , Anciano , Linfohistiocitosis Hemofagocítica/epidemiología , Linfohistiocitosis Hemofagocítica/diagnóstico , Estudios de Cohortes , Estudios Retrospectivos , Neoplasias/complicaciones , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/epidemiología
3.
Eur J Cancer ; 188: 20-28, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37178646

RESUMEN

BACKGROUND: Consensus guidelines outline that patients with primary retroperitoneal sarcoma (RPS) should be managed within specialist sarcoma centres (SSC). There is, however, a paucity of population-based data detailing incidence and outcomes in these patients. Hence, we aimed to evaluate patterns of care among RPS patients in England and compare outcomes for those undergoing surgery in high-volume specialist sarcoma centres (HV-SSC), low-volume SSC (LV-SSC), and non-SSC (N-SSC). METHODS: Data on patients diagnosed with primary RPS between 2013 and 2018 were extracted from NHS Digital's National Cancer Registration and Analysis Service using the national cancer registration dataset. Diagnostic pathways, treatment, and survival outcomes were compared between HV-SSC, LV-SSC, and N-SSC. Uni- and multivariate analyses were calculated. RESULTS: Of 1878 patients diagnosed with RPS, 1120 (60%) underwent surgery within 12 months of diagnosis, with 847 (76%) operated on at SSC; of these, 432 patients (51%) were operated on in HV-SSC, and 415 (49%) in LV-SSC. One- and 5-year estimated overall survival (OS) rates for patients undergoing surgery in N-SSC were 70.6% (95% confidence interval [CI]: 64.8-75.7) and 42.0% (CI: 35.9-47.9), compared to 85.0% (CI: 81.1-88.1) and 51.7% (CI: 46.6-56.6) in LV-SSC (p < 0.01), and 87.4% (CI: 83.9-90.2) and 62.8% (CI: 57.9-67.4) in HV-SSC, (p < 0.01). After adjusting for patient- and treatment-related factors, patients treated in HV-SSC were found to have significantly longer OS than those treated at LV-SSC, with an adjusted hazard ratio of 0.78 (CI: 0.62-0.96, p < 0.05). CONCLUSION: Patients with RPS undergoing surgery in HV-SSC have significantly better survival outcomes than those treated in N-SSC and L-SSC.


Asunto(s)
Neoplasias Retroperitoneales , Sarcoma , Neoplasias de los Tejidos Blandos , Humanos , Sarcoma/cirugía , Neoplasias Retroperitoneales/cirugía , Modelos de Riesgos Proporcionales , Inglaterra/epidemiología , Estudios Retrospectivos , Tasa de Supervivencia
4.
Hemasphere ; 6(11): e797, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36340911

RESUMEN

Hemophagocytic lymphohistiocytosis (HLH) is rare, results in high mortality, and is increasingly being diagnosed. We aimed to quantify the incidence of diagnosed HLH and examine temporal trends in relation to age and associated diseases. Using national linked electronic health data from hospital admissions and death certification cases of HLH that were diagnosed in England between January 1, 2003, and December 31, 2018. We calculated incidence rates of diagnosed HLH per million population by calendar year, age group, sex, and associated comorbidity (hematological malignancy, inflammatory rheumatological or bowel diseases [IBD]). We modeled trends in incidence and the interactions between calendar year, age, and associated comorbidity using Poisson regression. There were 1674 people with HLH diagnosed in England between 2003 and 2018. The incidence rate quadrupled (incidence rate ratio [IRR] 2018 compared to 2003: 3.88, 95% confidence interval [CI] 2.91 to 5.28), increasing 11% annually (adjusted IRR 1.11, 95% CI 1.09 to 1.12). There was a transition across age groups with greater increases in those aged 5-14 years of HLH associated with rheumatological disease/IBD compared with hematological malignancy, with similar increases in HLH associated with both comorbidities for those 15-54, and greater increases in HLH associated with hematological malignancies for those 55 years and older. The incidence of HLH in England has quadrupled between 2003 and 2018. Substantial variation in the incidence occurred with inflammatory rheumatological diseases/IBD-associated HLH increasing more among the younger age groups, whereas in older age groups, the largest increase was seen with hematological malignancy-associated HLH.

5.
Br J Haematol ; 199(5): 728-738, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36122574

RESUMEN

This analysis is the largest population-based study to date to provide contemporary and comprehensive epidemiological estimates of all third edition of the International Classification of Diseases for Oncology (ICD-O-3) coded Langerhans cell histiocytosis (LCH) from England. People of all ages were identified from the National Cancer Registration Dataset using ICD-O-3 morphologies 9751-9754 for neoplasms diagnosed in 2013-2019. A total of 658 patients were identified, of whom 324 (49%) were children aged <15 years. The age-standardised incidence rate was 4.46 (95% confidence interval [CI] 3.99-4.98) per million children and 1.06 (95% CI 0.94-1.18) per million adults aged ≥15 years. Prevalence of LCH was 9.95 (95% CI 9.14-10.81) per million persons at the end of 2019. The 1-year overall survival (OS) was 99% (95% CI 97%-100%) for children and 90% (95% CI 87%-93%) for adults. Those aged ≥60 years had poorer OS than those aged <15 years (hazard ratio [HR] 22.12, 95% CI 7.10-68.94; p < 0.001). People in deprived areas had lower OS than those in the least deprived areas (HR 5.36, 95% CI 1.16-24.87; p = 0.03). There will inevitably be other environmental factors and associations yet to be identified, and the continued standardised data collection will allow further evaluation of data over time. This will be increasingly important with developments in LCH management following the large collaborative international trials such as LCH IV.


Asunto(s)
Histiocitosis de Células de Langerhans , Neoplasias , Niño , Adulto , Humanos , Incidencia , Prevalencia , Histiocitosis de Células de Langerhans/epidemiología , Histiocitosis de Células de Langerhans/terapia , Sistema de Registros , Neoplasias/epidemiología
6.
Front Neurol ; 12: 658076, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34589042

RESUMEN

It has been reported that circNF1, a type of circular RNA (circRNA), promotes gastric cancer. This study aimed to analyze the role of circNF1 in glioblastoma (GBM). The expression of circNF1, mature miR-340, and miR-340 precursor in paired GBM and non-cancer tissues from GBM patients (n = 50) was analyzed by RT-qPCR. GBM cells were transfected with circNF1 siRNA, followed by the analysis of the expression of mature miR-340 and miR-340 precursor, to study the effects of circNF1 knockdown on the maturation of miR-340. The CCK-8 assay was carried out to explore the role of circNF1 and miR-340 in the proliferation of GBM cells. circNF1 expression was found to be upregulated in GBM and was correlated with patient survival. In glioma tissue, circNF1 was inversely correlated with mature miR-340, but not with the miR-340 precursor. In GBM cells, circNF1 siRNA silencing resulted in the upregulation of mature miR-340, but not the miR-340 precursor. The cell proliferation assay showed that circNF1 siRNA silencing and miR-340 overexpression decreased the proliferation of GBM cells. In addition, the miR-340a inhibitor suppressed the role of circNF1 siRNA silencing in cell proliferation. Therefore, circNF1 siRNA silencing may inhibit GBM cell proliferation by promoting the maturation of miR-340.

7.
Int J Cancer ; 148(4): 868-875, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-32838478

RESUMEN

Immune checkpoint inhibitors (CPIs) have radically changed outcomes for patients diagnosed with metastatic melanoma globally in the last 10 years, based on evidence of overall survival (OS) benefits generated from international randomised controlled trials (RCTs). Since RCTs do not always reflect real-world prescribing, we interrogated established national databases to track prescribing of CPIs approved for first line treatment of metastatic melanoma patients in England since 2014 and determined patient outcomes associated with OS, as well as treatment-related toxicity. Between April 2014 and March 2018, 5465 melanoma patients were diagnosed and treated with systemic anticancer therapy (SACT), 2322 of which received first-line CPIs. There was good 3-year OS concordance with RCT outcomes for ipilimumab (32%), ipinivo (56%) and nivolumab (51%), but OS was lower than expected for pembrolizumab (40%). Comparing patients prescribed ipinivo with those prescribed pembrolizumab, ipinivo-treated patients were younger (88% vs 49% patients <70 years, P < .001) and fitter (60% vs 38% patients with Eastern Cooperative Oncology Group [ECOG] performance status 0, P < .0001). Emergency hospital admission rates from the earliest and last treatment dates were higher for patients prescribed ipinivo (37% and 55%) compared to those prescribed pembrolizumab (17% and 29%). The 30-day mortality rates favoured ipinivo patients (3.8% ipinivo, 9.1% pembrolizumab, P < .0001) and likely reflected marked differences in median treatment durations: 63 (range 7-440) days for ipinivo and 192 (range 5-943) days for pembrolizumab. The dominant treatment-related condition linked to hospital admission was colitis, recorded for 25% of patients prescribed ipinivo compared to 4% of patients prescribed pembrolizumab. Our population data has demonstrated that RCT outcomes can be achieved in routine care settings with careful patient selection.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Melanoma/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados/uso terapéutico , Inglaterra , Femenino , Humanos , Ipilimumab/uso terapéutico , Estimación de Kaplan-Meier , Masculino , Melanoma/patología , Persona de Mediana Edad , Metástasis de la Neoplasia , Nivolumab/uso terapéutico , Evaluación de Resultado en la Atención de Salud/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Adulto Joven
8.
J Radiol Prot ; 39(2): 620-634, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31112514

RESUMEN

The potential for adverse health effects from internal exposure to Plutonium has been recognised since its discovery in the 1940s. However, in the absence of specific information, potential risks from Plutonium exposure have always largely been controlled through knowledge of radiation exposure risks in general, much of which comes from external radiation exposures. To try to obtain more direct estimates of potential internal exposure risks, epidemiological studies of Plutonium workers need to be conducted. Such epidemiological analyses require individual Plutonium exposure estimates that are as accurate and unbiased as possible. The UK Sellafield workforce includes one of the world's largest cohorts of Plutonium workers, which constitutes, by some considerable margin, the group of workers most comprehensively monitored for internal exposure to this alpha-particle-emitter. However, for several hundred workers employed at the start of Plutonium work at the facility, during the period from 1952 through to 1963, the historical urinalysis results available cannot provide sufficiently accurate and unbiased exposure assessments needed for use in epidemiological studies. Consequently, these early workers have had to be excluded from epidemiological analyses and this has significantly reduced the power of these studies. A promising quantitative methodology to overcome the issue of missing or deficient exposure data, is to use exposure data from other sources to estimate the average exposure a 'typical worker' would have received, and to collate this information for specific occupations and years. This approach is called a Job-Exposure Matrix (JEM). Work on a pilot study to construct a population-specific quantitative JEM for the early Plutonium workers at Sellafield during 1952-1963, for whom reliable urinalysis results do not exist, has shown the potential for a JEM approach to produce more reliable and useful exposure estimates for epidemiological research.


Asunto(s)
Plantas de Energía Nuclear , Exposición Profesional , Plutonio , Exposición a la Radiación , Humanos , Exposición Profesional/análisis , Plutonio/efectos adversos , Plutonio/orina , Exposición a la Radiación/análisis , Factores de Tiempo , Reino Unido , Urinálisis
9.
Radiat Res ; 191(1): 60-66, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30398393

RESUMEN

Plutonium is a radiologically significant alpha-particle emitter. The potential for adverse health effects from internal exposures due to plutonium intakes has been recognized since the 1940s. The workforce of the Sellafield nuclear facility (Cumbria, UK), includes one of the world's most important groups of plutonium-exposed workers for studying the potential health risks of this internal exposure. However, for several hundred workers employed at the start of plutonium work at the facility (1952-1963), historical monitoring records based on measurements of urinary excretion of plutonium are not sufficiently reliable to provide the accurate and unbiased exposure assessments needed for epidemiological studies. Consequently, these early workers have had to be excluded from such studies, significantly reducing their power. We constructed a population-specific quantitative job exposure matrix (JEM) to estimate the average intakes of "typical plutonium workers" in this period, from 1952-1963, and assessed its validity and sensitivity to exposure assessment decisions. We conducted internal cross-validation using an a priori 10% extracted sample to evaluate reliability of estimates, explored JEM sensitivity to assumptions in the exposure assessment, and assessed the impact of uncertainty in urinalysis measurements on the precision of annual intake estimates using Markov Chain Monte Carlo (MCMC) methodology. Pairwise correlations ( RP) of estimated (JEM) and measured (10% sample) annual intakes were moderate to high ( RP > 0.4) for 10 out of 13 JEM groups, while absolute differences were <20% for 11 out of 13 JEM groups. There was little evidence of a temporal trend in correlations ( P = 0.13) or absolute differences ( P = 0.34). The median JEM-derived cumulative intake of 95.2 (IQR, 55.0-130.0) Bq was comparable to those based on alternative assumptions in the exposure assessment (median range, 95.2-100.0 Bq; 75th percentiles, 130.0-146.0 Bq). Measurement error simulation resulted in a 40-60% reduced median cumulative intake but higher maximum cumulative intakes. The JEM finds a balance between reliability and precision that makes it useful for epidemiological purposes and is relatively insensitive to specific choices in the exposure assessment. This JEM will allow the inclusion of workers with longest follow-up and who could not be included up until now in epidemiological studies without introducing significant bias.


Asunto(s)
Exposición Profesional , Plutonio/efectos adversos , Exposición a Riesgos Ambientales , Humanos , Cadenas de Markov , Método de Montecarlo , Plutonio/orina , Monitoreo de Radiación , Reproducibilidad de los Resultados , Reino Unido
10.
J Fam Plann Reprod Health Care ; 43(4): 281-288, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28473617

RESUMEN

BACKGROUND: Reducing unplanned pregnancy in Scotland is a key government objective. Long-acting reversible contraception (LARC) is a cost-effective way to reduce unintended pregnancy. Abortion and teenage pregnancy rates are highest in the most deprived areas. One possible explanation could be contraceptive prescribing inequality. This study examined the relationship between area deprivation measured by the Scottish Index of Multiple Deprivation and LARC prescription. METHODS: Using Scottish electronic prescribing data from primary care and sexual and reproductive health clinics, this study analysed female Lothian residents with a valid postcode aged 16-49 years who received a contraceptive prescription from 1 April 2012 to 31 March 2014. Prescription of LARC (intrauterine, implant or injectable contraceptive) compared with non-LARC (oral pill, patch, ring or diaphragm) was examined. Logistic regression was performed adjusting for age group and prescription location. RESULTS: A total of 90 150 women were included; 21.1% of prescriptions were LARC and 15.3% vLARC (intrauterine method or implant). Women residing in the most deprived quintile (Q1) and prescribed contraception received a significantly higher proportion of LARC than quintiles 2-5 (Q2-5). Odds ratios compared with Q1 were: Q2 0.86, Q3 0.77, Q4 0.59 and Q5 0.51. Women in quintile 1 were also significantly more likely to receive vLARC than quintiles 2-5. CONCLUSION: Women in the most deprived quintile in Lothian who are prescribed contraception are significantly more likely to receive LARC and vLARC compared with women in less deprived quintiles.

11.
J Radiol Prot ; 36(1): R1-22, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26861451

RESUMEN

Any potential health effects of radiation emitted from radionuclides deposited in the bodies of workers exposed to radioactive materials can be directly investigated through epidemiological studies. However, estimates of radionuclide exposure and consequent tissue-specific doses, particularly for early workers for whom monitoring was relatively crude but exposures tended to be highest, can be uncertain, limiting the accuracy of risk estimates. We review the use of job-exposure matrices (JEMs) in peer-reviewed epidemiological and exposure assessment studies of nuclear industry workers exposed to radioactive materials as a method for addressing gaps in exposure data, and discuss methodology and comparability between studies. We identified nine studies of nuclear worker cohorts in France, Russia, the USA and the UK that had incorporated JEMs in their exposure assessments. All these JEMs were study or cohort-specific, and although broadly comparable methodologies were used in their construction, this is insufficient to enable the transfer of any one JEM to another study. Moreover there was often inadequate detail on whether, or how, JEMs were validated. JEMs have become more detailed and more quantitative, and this trend may eventually enable better comparison across, and the pooling of, studies. We conclude that JEMs have been shown to be a valuable exposure assessment methodology for imputation of missing exposure data for nuclear worker cohorts with data not missing at random. The next step forward for direct comparison or pooled analysis of complete cohorts would be the use of transparent and transferable methods.


Asunto(s)
Biometría/métodos , Exposición Profesional/análisis , Plutonio/efectos adversos , Francia , Humanos , Exposición Profesional/efectos adversos , Federación de Rusia , Reino Unido , Estados Unidos
12.
Health Technol Assess ; 19(93): 1-115, v-vi, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26560448

RESUMEN

BACKGROUND: The development of the capability and capacity to evaluate the outcomes of trials of complex interventions is a key priority of the National Institute for Health Research (NIHR) and the Medical Research Council (MRC). The evaluation of complex treatment programmes for mental illness (e.g. cognitive-behavioural therapy for depression or psychosis) not only is a vital component of this research in its own right but also provides a well-established model for the evaluation of complex interventions in other clinical areas. In the context of efficacy and mechanism evaluation (EME) there is a particular need for robust methods for making valid causal inference in explanatory analyses of the mechanisms of treatment-induced change in clinical outcomes in randomised clinical trials. OBJECTIVES: The key objective was to produce statistical methods to enable trial investigators to make valid causal inferences about the mechanisms of treatment-induced change in these clinical outcomes. The primary objective of this report is to disseminate this methodology, aiming specifically at trial practitioners. METHODS: The three components of the research were (1) the extension of instrumental variable (IV) methods to latent growth curve models and growth mixture models for repeated-measures data; (2) the development of designs and regression methods for parallel trials; and (3) the evaluation of the sensitivity/robustness of findings to the assumptions necessary for model identifiability. We illustrate our methods with applications from psychological and psychosocial intervention trials, keeping the technical details to a minimum, leaving the reporting of the more theoretical and mathematically demanding results for publication in appropriate specialist journals. RESULTS: We show how to estimate treatment effects and introduce methods for EME. We explain the use of IV methods and principal stratification to evaluate the role of putative treatment effect mediators and therapeutic process measures. These results are extended to the analysis of longitudinal data structures. We consider the design of EME trials. We focus on designs to create convincing IVs, bearing in mind assumptions needed to attain model identifiability. A key area of application that has become apparent during this work is the potential role of treatment moderators (predictive markers) in the evaluation of treatment effect mechanisms for personalised therapies (stratified medicine). We consider the role of targeted therapies and multiarm trials and the use of parallel trials to help elucidate the evaluation of mediators working in parallel. CONCLUSIONS: In order to demonstrate both efficacy and mechanism, it is necessary to (1) demonstrate a treatment effect on the primary (clinical) outcome, (2) demonstrate a treatment effect on the putative mediator (mechanism) and (3) demonstrate a causal effect from the mediator to the outcome. Appropriate regression models should be applied for (3) or alternative IV procedures, which account for unmeasured confounding, provided that a valid instrument can be identified. Stratified medicine may provide a setting where such instruments can be designed into the trial. This work could be extended by considering improved trial designs, sample size considerations and measurement properties. FUNDING: The project presents independent research funded under the MRC-NIHR Methodology Research Programme (grant reference G0900678).


Asunto(s)
Biomarcadores , Interpretación Estadística de Datos , Trastornos Mentales/terapia , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Humanos , Trastornos Mentales/psicología , Análisis de Regresión , Proyectos de Investigación , Evaluación de la Tecnología Biomédica
13.
Environ Sci Technol ; 49(1): 562-9, 2015 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-25407029

RESUMEN

Use of pesticides in agriculture may lead to downstream exposure of farmers' families to pesticide residues inadvertently taken home. Identification of the independent contribution of different exposure pathways from the farmer to their children can provide clear targets to reduce exposure of farmers' children. Individual contributions of different pesticide transfer exposure pathways were investigated using structural equation modeling methods, and the benefits of these methods compared to standard multiple regression are described. A total of 72 Thai families, consisting of a farmer, a spouse, and a child, participated in this study. Family members completed a questionnaire and self-collected three spot morning urine samples in the spraying season. Urine samples were analyzed for diethyl phosphate, diethyl thiophosphate, diethyl dithiophosphate, dimethyl phosphate, dimethyl thiophosphate, and dimethyl dithiophosphate. A path model was developed based on an a priori hypothesized framework to examine the individual contributions of different exposure pathways that may directly or indirectly affect transfer of pesticide residues from farmers to their children. Transfer from the farmer to the child occurs indirectly, primarily through transfer to the spouse in the first instance, but also through contamination of the home environment. Clear targets for interventions are directly the reduction of farmers' take-home exposures and indirectly frequent cleaning of the home to avoid buildup of pesticide residues.


Asunto(s)
Agricultura , Monitoreo del Ambiente , Familia , Modelos Teóricos , Residuos de Plaguicidas/análisis , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tailandia , Adulto Joven
14.
Clin Trials ; 10(5): 709-19, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24000376

RESUMEN

BACKGROUND: The development of personalised (stratified) medicine is intrinsically dependent on an understanding of treatment-effect mechanisms (effects on therapeutic targets that mediate the effect of the treatment on clinical outcomes). There is a need for clinical trial data for the joint evaluation of treatment efficacy, the utility of predictive markers as indicators of treatment efficacy, and the mediational mechanisms proposed as the explanation of these effects. PURPOSE: (1) To review the problem of confounding (common causes) for the drawing of valid inferences concerning treatment-effect mechanisms, even when the data have been generated using a randomised controlled trial, and (2) to suggest and illustrate solutions to this problem of confounding. RESULTS: We illustrate the potential of the predictive biomarker stratified design, together with baseline measurement of all known prognostic markers, to enable us to evaluate both the utility of the predictive biomarker in such a stratification and, perhaps more importantly, to estimate how much of the treatment's effect is actually explained by changes in the putative mediator. The analysis strategy involves the use of instrumental variable (IV) regression, using the treatment by predictive biomarker interaction as an IV - a refined, much more powerful, and (in the present context) subtle use of Mendelian randomisation. CONCLUSION: Personalised (stratified) medicine and treatment-effect mechanisms evaluation are inextricably linked. Stratification without corresponding mechanisms evaluation lacks credibility. In the presence of mediator-outcome confounding, mechanisms evaluation is dependent on stratification for its validity. Both stratification and treatment-effect mediation can be evaluated using a biomarker stratified trial design together with detailed baseline measurement of all known prognostic biomarkers and other prognostic covariates. Direct and indirect (mediated) effects should be estimated through the use of IV methods (the IV being the predictive marker by treatment interaction) together with adjustments for all known prognostic markers (confounders) - the latter adjustments contributing to increased precision (as in a conventional analysis of treatment effects) rather than bias reduction.


Asunto(s)
Biomarcadores , Ensayos Clínicos como Asunto/métodos , Medicina de Precisión/métodos , Antagonistas Adrenérgicos beta/uso terapéutico , Neoplasias de la Mama/genética , Causalidad , Factores de Confusión Epidemiológicos , Humanos , Hipertensión/tratamiento farmacológico , Valor Predictivo de las Pruebas , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Receptor ErbB-2
15.
Gene ; 501(1): 24-32, 2012 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-22575711

RESUMEN

Tobacco is one of the most important economic and agricultural crops worldwide. miRNAs have been increasingly acknowledged for their important roles in different biological processes of tobacco. However, few miRNAs have been identified so far in tobacco impeding the development of new tobacco strains with better properties. In this study, high-throughput sequencing technology was employed to identify novel tobacco miRNAs. A total of 84 potential miRNAs were obtained in tobacco, including 33 conserved and 51 novel miRNAs. Tissue-specific and topping-related miRNAs were identified. A tobacco miRNA microarray was also constructed to investigate miRNA expression patterns in different tissues, and their expression patterns were further validated by qRT-PCR and Northern Blot. Finally, the potential targets of these miRNAs were predicted based on a sequence homology search. Thus, in the current study, we have performed the comprehensive analysis of tobacco miRNAs, including their identification, expression pattern and target prediction. Our study opens a new avenue for further elucidation for their roles underlying the regulation of diversity of physiological processes.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , MicroARNs/genética , Nicotiana/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Northern Blotting , Reacción en Cadena en Tiempo Real de la Polimerasa
16.
Appl Microbiol Biotechnol ; 87(1): 343-52, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20437237

RESUMEN

DNA microarray technology has been extensively used for gene expression analysis of both eukaryotic and prokaryotic organisms. For eukaryotic gene expression profiling, the poly(A)-based reverse transcription of messenger RNA (mRNA) followed by T7 RNA polymerase-based in vitro transcription is generally required to produce enough RNA targets for hybridization with the microarray chips. However, the same method cannot be directly applied to prokaryotic mRNAs due to the lack of poly(A) sequences at the 3' ends. Conventional methods usually require large amounts of starting RNAs and lead to high background noise. Recently developed amplification methods enable smaller amounts of prokaryotic RNA to be used from samples with species-specific primers, oligo(dT) primers, or random primers. In this study, three target preparation methods, including the direct labeling, polyadenylation-involved oligo-dT priming, and random priming amplification (respectively referred to as DL, PAOD, and RPA hereafter) were evaluated through expression profiling of a heat shock model of Escherichia coli. The PAOD method was found to be more sensitive and more specific in differential gene expression measurements than either DL and RPA, even when the E. coli RNA was only a small proportion of the simulated eukaryotic host RNA. The results suggest that PAOD is the preferred target preparation method for prokaryotic transcriptome.


Asunto(s)
Escherichia coli/genética , Eucariontes/genética , Perfilación de la Expresión Génica/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , ARN Bacteriano/genética , Regulación Bacteriana de la Expresión Génica
17.
J Environ Manage ; 91(2): 403-10, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19819612

RESUMEN

This paper uses a randomized controlled trial to test whether doorstep canvassing can raise participation in kerbside recycling. Existing research shows that canvassing can confront negative attitudes, increase understanding and resolve structural obstacles, but there is less known about the longitudinal effects of such interventions, which may fall away over time. 194 streets in Trafford, in the North West of England, UK were randomly assigned into a treatment and a control group. All households in the treatment group were visited by canvassers who were trained to promote and encourage recycling. Recycling participation rates for all households were measured by observing bin set out rates over a three-week period. Measurement was done before and after the canvassing campaign and then again three months later to see if the intervention had been effective in raising participation rates. Random-effects multilevel regression models, controlling for baseline recycling, street size, deprivation and size of ethnic minority population, show that the canvassing raised recycling participation rates for the treatment group compared to the control group, but there was a decline in the impact of the intervention over time. The intervention was more effective on streets with low levels of recycling at baseline.


Asunto(s)
Participación de la Comunidad , Conservación de los Recursos Naturales , Inglaterra , Humanos
18.
Brain Res ; 1286: 230-8, 2009 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-19563788

RESUMEN

Long term subthalamic nucleus (STN) high frequency stimulation (HFS) can improve most symptoms of Parkinson's disease (PD) patients and decrease the dosage of antiparkinsonian drug such as Madopar. The mechanism of STN HFS for PD still remains elusive. We hypothesize that the level of dopamine (DA) and its metabolites in the corpus striatum is increased after long term STN HFS. The aim of this study was to examine the DA and its metabolites in the extracellular space of corpus striatum in hemiparkinsonian monkeys during long term STN HFS. Four rhesus monkeys were induced to hemiparkinsonian models by injecting 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) through right internal carotid artery. Then two of them were underwent long term right STN HFS for the subsequent microdialysis sessions. Four microdialysis probe cannulas were implanted into bilateral putamen and caudate nucleus respectively. The microdialysis probe was put into the microdialysis probe cannula of bilateral putamen and caudate nucleus. Dialysates of extracellular space in corpus striatum were collected prior to STN HFS, and subsequently 8 h, 1 week, 1 month, 2 months, 8 months and 10 months after STN HFS. The level of DA and its metabolites were determined by high performance liquid chromatography and subthalamic nucleus electrochemical detection (HPLC-ECD). HFS significantly improved PD symptoms of the monkeys. Rotation evoked by apomorphine (APO) disappeared immediately after HFS pulse generator was turned on. The levels of DA and its metabolites in putamen and caudate nucleus of electrode side increased significantly at different time points after stimulation. Long term STN HFS significantly improved symptoms of hemiparkinsonian rhesus monkey, which might be due to the increase of dopamine and/or its metabolites in corpus striatum.


Asunto(s)
Cuerpo Estriado/metabolismo , Estimulación Encefálica Profunda , Dopamina/metabolismo , Trastornos Parkinsonianos/metabolismo , Trastornos Parkinsonianos/terapia , Núcleo Subtalámico/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Inmunohistoquímica , Macaca mulatta , Microdiálisis , Tiempo
19.
RNA ; 14(5): 836-43, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18356539

RESUMEN

High-salinity, drought, and low temperature are three common environmental stress factors that seriously influence plant growth and development worldwide. Recently, microRNAs (miRNAs) have emerged as a class of gene expression regulators that have also been linked to stress responses. However, the relationship between miRNA expression and stress responses is just beginning to be explored. Here, we identified 14 stress-inducible miRNAs using microarray data in which the effects of three abiotic stresses were surveyed in Arabidopsis thaliana. Among them, 10 high-salinity-, four drought-, and 10 cold-regulated miRNAs were detected, respectively. miR168, miR171, and miR396 responded to all of the stresses. Expression profiling by RT-PCR analysis showed great cross-talk among the high-salinity, drought, and cold stress signaling pathways. The existence of stress-related elements in miRNA promoter regions provided further evidence supporting our results. These findings extend the current view about miRNA as ubiquitous regulators under stress conditions.


Asunto(s)
Arabidopsis/genética , Arabidopsis/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , ARN de Planta/genética , ARN de Planta/metabolismo , Secuencia de Bases , Frío , Cartilla de ADN/genética , Desastres , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Análisis de Secuencia por Matrices de Oligonucleótidos , Regiones Promotoras Genéticas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Salinidad , Transducción de Señal
20.
Zhonghua Wai Ke Za Zhi ; 45(24): 1682-4, 2007 Dec 15.
Artículo en Chino | MEDLINE | ID: mdl-18476526

RESUMEN

OBJECTIVE: To investigate the influence of high frequency stimulation of the subthalamic nucleus on the levels of amino acids neurotransmitters in striatum of hemi-parkinsonian monkeys. METHODS: Two rhesus monkeys were successfully prepared for the subsequent microdialysis sessions. Collecting the dialysate before turning on the pulse generator, and collecting at 1 week, 1, 8 and 12 months after high frequency stimulation of the subthalamic nucleus. The level of Glu, GABA and Tau were determined by high performance liquid chromatography and fluorometric detection (HPLC-FD). RESULTS: After high frequency stimulation (HFS), PD symptoms of monkeys significantly improved. The levels of Glu in putamen and caudate nucleus of electrodes side at 1 week, 1, 8 and 12 months were increased significantly. The levels of GABA in putamen and caudate nucleus of electrodes side at 1 week, 1 month increased significantly compared with before turning on the pulse generator while decreased at 8, 12 months. The level of Tau in putamen and caudate nucleus increased significantly. CONCLUSION: Long-term STN HFS can increase the level of glutamate and taurine, while decrease the level of GABA in putamen and caudate nucleus of electrodes side. It improves symptoms of hemi-parkinsonian rhesus monkey significantly.


Asunto(s)
Aminoácidos/metabolismo , Cuerpo Estriado/metabolismo , Estimulación Encefálica Profunda/métodos , Neurotransmisores/metabolismo , Enfermedad de Parkinson Secundaria/terapia , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , Animales , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Ácido Glutámico/metabolismo , Macaca mulatta , Microdiálisis , Neurotoxinas/toxicidad , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/metabolismo , Núcleo Subtalámico , Taurina/metabolismo , Ácido gamma-Aminobutírico/metabolismo
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