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1.
Environ Monit Assess ; 193(6): 355, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-34028631

RESUMEN

Evaporation is an important meteorological variable that has a great impact on water resources. In the current research, climatology data, and seasonal coefficient have been used to estimate monthly pan evaporation (Epan) for 2005-2018 study years at four selected stations of the Urmia Lake basin with Dsa and six selected stations of Gavkhouni basin with Bsk climate categories, in Iran. Estimation of monthly Epan was performed using data-driven methods such as artificial neural networks (ANNs), adaptive neuro-fuzzy inference system (ANFIS), and gene expression programming (GEP) as well as wavelet-hybrids (WANN, WANFIS, and WGEP). Based on the evaluation criteria, the WGEP model performance was better than the other models in estimating the monthly Epan. The results indicated that WGEP and ANN are the best and poorest models for all stations without affecting the climate condition of basins. The values of RMSE for WGEP model for stations of Urmia Lake and Gavkhouni basins were varied from 15.839 to 26.727 and 20.651 to 70.318, respectively. Also, the values of RMSE for ANN model for stations of Urmia Lake and Gavkhouni basins were varied from 29.397 to 38.452 and 30.635 to 85.237, respectively. The model's performance was improved as a result of considering the data noise elimination and applying seasonal coefficient to estimate Epan of various climatic conditions. This study with presenting mathematical equations for estimating monthly Epan has a significant impact on the management and planning of water resources policymakers in the future.


Asunto(s)
Monitoreo del Ambiente , Lagos , Irán , Redes Neurales de la Computación
2.
Gut ; 68(3): 487-498, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-29363536

RESUMEN

OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive tumour thought to arise from ductal cells via pancreatic intraepithelial neoplasia (PanIN) precursor lesions. Modelling of different genetic events in mice suggests both ductal and acinar cells can give rise to PDAC. However, the impact of cellular context alone on tumour development and phenotype is unknown. DESIGN: We examined the contribution of cellular origin to PDAC development by inducing PDAC-associated mutations, KrasG12D expression and Trp53 loss, specifically in ductal cells (Sox9CreER;KrasLSL-G12D;Trp53flox/flox ('Duct:KPcKO ')) or acinar cells (Ptf1aCreER;KrasLSL-G12D;Trp53flox/flox ('Acinar:KPcKO ')) in mice. We then performed a thorough analysis of the resulting histopathological changes. RESULTS: Both mouse models developed PDAC, but Duct:KPcKO mice developed PDAC earlier than Acinar:KPcKO mice. Tumour development was more rapid and associated with high-grade murine PanIN (mPanIN) lesions in Duct:KPcKO mice. In contrast, Acinar:KPcKO mice exhibited widespread metaplasia and low-grade as well as high-grade mPanINs with delayed progression to PDAC. Acinar-cell-derived tumours also had a higher prevalence of mucinous glandular features reminiscent of early mPanIN lesions. CONCLUSION: These findings indicate that ductal cells are primed to form carcinoma in situ that become invasive PDAC in the presence of oncogenic Kras and Trp53 deletion, while acinar cells with the same mutations appear to require a prolonged period of transition or reprogramming to initiate PDAC. Our findings illustrate that PDAC can develop in multiple ways and the cellular context in which mutations are acquired has significant impact on precursor lesion initiation, disease progression and tumour phenotype.


Asunto(s)
Carcinoma Ductal Pancreático/patología , Neoplasias Pancreáticas/patología , Células Acinares/metabolismo , Células Acinares/patología , Animales , Carcinoma in Situ/genética , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patología , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación , Clasificación del Tumor , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fenotipo , Lesiones Precancerosas/genética , Lesiones Precancerosas/metabolismo , Lesiones Precancerosas/patología , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Factores de Tiempo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
3.
Sci Rep ; 11(1): 22831, 2021 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-34819559

RESUMEN

Water use by the agricultural sector along with inefficient irrigation methods and climate change has led to the depletion and insecurity of water resources and consequent instability of the agricultural system. Defining benchmarks and comparing them is essential for sustainable system management performance. The sustainability performance of an agricultural system depends on various factors related to water, energy, and food. This study selects and ranks sustainability performance indicators (SPIs) of agricultural systems with the analytical hierarchy process (AHP). Expert opinions on agricultural sustainability were obtained from Iran's Regional Water Organization. The factors and variables affecting the management of water resources in agricultural systems in a basin area are evaluated with 17 SPIs (10 indicators of water resources sustainability, 3 energy sustainability indicators, and 4 food sustainability indicators) that measure the sustainability of agricultural systems. The AHP reduced the number of indicators to a small number of effective indicators. Results of pairwise comparison and the subsequent determination of the weight of each indicator show that the indicators of water consumption, groundwater level stability, vulnerability of water resources, and water stress have the largest weights (i.e., importance) for agricultural system sustainability at the basin scale. These selected indicators can be applied to agricultural water systems (AWSs).

4.
Cancer Discov ; 11(3): 638-659, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33060108

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is characterized by extensive desmoplasia, which challenges the molecular analyses of bulk tumor samples. Here we FACS-purified epithelial cells from human PDAC and normal pancreas and derived their genome-wide transcriptome and DNA methylome landscapes. Clustering based on DNA methylation revealed two distinct PDAC groups displaying different methylation patterns at regions encoding repeat elements. Methylationlow tumors are characterized by higher expression of endogenous retroviral transcripts and double-stranded RNA sensors, which lead to a cell-intrinsic activation of an interferon signature (IFNsign). This results in a protumorigenic microenvironment and poor patient outcome. Methylationlow/IFNsignhigh and Methylationhigh/IFNsignlow PDAC cells preserve lineage traits, respective of normal ductal or acinar pancreatic cells. Moreover, ductal-derived Kras G12D/Trp53 -/- mouse PDACs show higher expression of IFNsign compared with acinar-derived counterparts. Collectively, our data point to two different origins and etiologies of human PDACs, with the aggressive Methylationlow/IFNsignhigh subtype potentially targetable by agents blocking intrinsic IFN signaling. SIGNIFICANCE: The mutational landscapes of PDAC alone cannot explain the observed interpatient heterogeneity. We identified two PDAC subtypes characterized by differential DNA methylation, preserving traits from normal ductal/acinar cells associated with IFN signaling. Our work suggests that epigenetic traits and the cell of origin contribute to PDAC heterogeneity.This article is highlighted in the In This Issue feature, p. 521.


Asunto(s)
Carcinoma Ductal Pancreático/etiología , Carcinoma Ductal Pancreático/metabolismo , Metilación de ADN , Interferones/metabolismo , Neoplasias Pancreáticas/etiología , Neoplasias Pancreáticas/metabolismo , Secuencias Repetitivas de Ácidos Nucleicos , Carcinoma Ductal Pancreático/mortalidad , Carcinoma Ductal Pancreático/patología , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Islas de CpG , Progresión de la Enfermedad , Susceptibilidad a Enfermedades , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Modelos Biológicos , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Pronóstico , Reproducibilidad de los Resultados , Transducción de Señal , Transcriptoma , Microambiente Tumoral/genética
5.
J Caring Sci ; 3(2): 121-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25276755

RESUMEN

INTRODUCTION: The management of asthma during adolescence has specific challenges and is likely influenced, to some extent, by the patient's belief in their ability to affect change, their self-efficacy. Bolstering self-efficacy could potentially improve an adolescent's ability to self-manage their asthma. The aim of this study was to examine the effects of a triggers' educational-modifying intervention on self-efficacy among adolescents diagnosed with asthma living in Iran. METHODS: Sixty adolescents, aged 12 to 18 years, diagnosed with asthma participated in this randomized clinical trial. Participants randomly assigned to the control group received standard care while those assigned to the experimental group participated in a 5 week, nurse led, triggers modifying educational intervention in specialized clinics of lung in Tabriz, Iran. The self-efficacy scale developed by Bursh et al., was used for data collection. RESULTS: The level of self- efficacy in two groups before intervention was not statistically significant, while the post intervention measures were statistically significant. Intervention was effective in improving adolescents' self-efficacy. CONCLUSION: Since this type of intervention has the potential to improve Self- efficacy in adolescents with asthma, it is suggested that adolescence directly education about asthma triggers along with modulating triggers will be of value and parent-centered could be diminished. The need for such interventions emphasizes in clinic and outpatient clinics.

6.
J Caring Sci ; 2(1): 73-82, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25276712

RESUMEN

INTRODUCTION: Controlling over allergens and environmental irritants is one of the essential elements of controlling asthma. Asthma control in adolescents is a challenge. The current study was performed with the goal of investigating the effect of an educational and modifying intervention about asthma triggers on asthma control among adolescents. METHODS: The current study was a randomized clinical trial. 60 adolescents of 12-18 years of age participated in this study. The participants were randomly divided into the two control and experimental groups. The Juniper's Asthma Control Questionnaire was completed by the adolescents before and 5 weeks after the intervention. Training sessions, planning for modification of asthma triggers and telephone follow-up were performed in the experimental group. RESULTS: There was a significant difference between the asthma control score before and after the intervention in the control and experimental groups. The asthma control status improved in the experimental group. In other words, the educational interventions to modify asthma triggers were effective in improving asthma control. CONCLUSION: Since this intervention method can improve the asthma control in adolescents, it is recommended that adolescents directly participate in such programs about asthma triggers and the education become less parent-centred. Moreover, the necessity of such an intervention in clinics and outpatient clinics is emphasized.

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