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1.
J Alzheimers Dis ; 82(1): 421-433, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34024820

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is characterized by progressive deterioration of cognitive functions and may be preceded by mild cognitive impairment (MCI). Evidence shows changes in pupil and vergence responses related to cognitive processing of visual information. OBJECTIVE: Here we test the hypothesis that MCI and AD are associated with specific patterns in vergence and pupil responses. METHODS: We employed a visual oddball task. In the distractor condition (80%of the trials), a blue stimulus was presented whereas in the target condition (20%of trials) it was red. Participants (23 Controls, 33 MCI patients, and 18 AD patients) were instructed to press a button when a target appeared. RESULTS: Participants briefly converged their eyes 200 ms after stimulus presentation. In controls, this transient peak response was followed by a delay response to targets but not to distractor stimuli. In the patient groups, delay responses to distractors were noticed. Consequently, the differential vergence response was strong in the control group, weak in the MCI group, and absent in the AD group. Pupils started to dilate 500-600 ms after the appearance of a target but slightly contracted after the presentation of a distractor. This differential pupil response was strongest in the AD group. CONCLUSION: Our findings support the idea of a role of vergence and pupil responses in attention and reveal altered responses in MCI and AD patients. Further studies should assess the value of vergence and pupil measurements as an objective support tool for early diagnosis of AD.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Disfunción Cognitiva/fisiopatología , Movimientos Oculares/fisiología , Pupila/fisiología , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Medidas del Movimiento Ocular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Percepción Visual
2.
BMC Cancer ; 21(1): 414, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33858386

RESUMEN

BACKGROUND: Colorectal cancer has increased in Middle Eastern countries and exposure to environmental pollutants such as heavy metals has been implicated. However, data linking them to this disease are generally lacking. This study aimed to explore the spatial pattern of age-standardized incidence rate (ASR) of colon cancer and its potential association with the exposure level of the amount of heavy metals existing in rice produced in north-eastern Iran. METHODS: Cancer data were drawn from the Iranian population-based cancer registry of Golestan Province, north-eastern Iran. Samples of 69 rice milling factories were analysed for the concentration levels of cadmium, nickel, cobalt, copper, selenium, lead and zinc. The inverse distance weighting (IDW) algorithm was used to interpolate the concentration of this kind of heavy metals on the surface of the study area. Exploratory regression analysis was conducted to build ordinary least squares (OLS) models including every possible combination of the candidate explanatory variables and chose the most useful ones to show the association between heavy metals and the ASR of colon cancer. RESULTS: The highest concentrations of heavy metals were found in the central part of the province and particularly counties with higher amount of cobalt were shown to be associated with higher ASR of men with colon cancer. In contrast, selenium concentrations were higher in areas with lower ASR of colon cancer in men. A significant regression equation for men with colon cancer was found (F(4,137) = 38.304, P < .000) with an adjusted R2 of 0.77. The predicted ASR of men colon cancer was - 58.36 with the coefficients for cobalt = 120.33; cadmium = 80.60; selenium = - 6.07; nickel = - 3.09; and zinc = - 0.41. The association of copper and lead with colon cancer in men was not significant. We did not find a significant outcome for colon cancer in women. CONCLUSION: Increased amounts of heavy metals in consumed rice may impact colon cancer incidence, both positively and negatively. While there were indications of an association between high cobalt concentrations and an increased risk for colon cancer, we found that high selenium concentrations might instead decrease the risk. Further investigations are needed to clarify if there are ecological or other reasons for these discrepancies. Regular monitoring of the amount of heavy metals in consumed rice is recommended.


Asunto(s)
Neoplasias del Colon/epidemiología , Neoplasias del Colon/etiología , Metales Pesados/efectos adversos , Susceptibilidad a Enfermedades , Femenino , Sistemas de Información Geográfica , Geografía Médica , Humanos , Irán/epidemiología , Masculino , Vigilancia de la Población , Análisis Espacial , Oligoelementos
3.
BMC Res Notes ; 14(1): 91, 2021 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-33750480

RESUMEN

OBJECTIVES: Gastric cancer (GC) is a multifactorial disease and the fifth most frequent diagnosed cancer worldwide. It accounts for one third of cancer-related mortalities. Geospatial analysis using geographical information systems (GIS) can provide an efficient solution to identify spatial disparities associated with GC. As such, GIS enables policymakers to control cancer in a better way and identify the regions where interventions are needed. This study aims to publish a comprehensive dataset, which was applied to conduct a spatial analysis of GC patients in the city of Mashhad, Iran. DATA DESCRIPTION: We provide a personal geodatabase, a Microsoft Access database that can store, query, and manage both spatial and non-spatial data, which contains four feature classes. "Male_Stomach_Cancer_Patients" and "Female_Stomach_Cancer_Patients" are point feature classes, which show the age and geographical location of 1156 GC cancer patients diagnosed between 2014 and 2017. "Air_Polution_Mashhad" is another point feature class that reveals the amount of six air pollutants, which was taken from Mashhad Environmental Pollutants Monitoring Center between 2017 and 2018. Finally, "Stomach_Cancer_and_Risk_Factors" is a polygon feature class of neighborhood division of Mashhad, consisting of contributor risk factors including dietary habits, smoking, alcohol use, body mass index and population by age groups for all 165 city neighborhoods.


Asunto(s)
Contaminación del Aire , Neoplasias Gástricas , Ciudades , Femenino , Humanos , Irán , Estilo de Vida , Masculino , Factores de Riesgo , Neoplasias Gástricas/epidemiología
4.
Sensors (Basel) ; 19(6)2019 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-30871252

RESUMEN

GNSS-based applications are susceptible to different threats, including radio frequency interference. Ensuring that the new applications can be validated against the latest threats supports the wider adoption and success of GNSS in higher value markets. Therefore, the availability of standardized GNSS receiver testing procedures is central to developing the next generation of receiver technologies. The EU Horizon2020 research project STRIKE3 (Standardization of GNSS Threat reporting and Receiver testing through International Knowledge Exchange, Experimentation and Exploitation) proposed standardized test procedures to validate different categories of receivers against real-world interferences, detected at different monitoring sites. This paper describes the recorded interference signatures, their use in standardized test procedures, and analyzes the result for two categories of receivers, namely mass-market and professional grade. The result analysis in terms of well-defined receiver key performance indicators showed that performance of both receiver categories was degraded by the selected interference threats, although there was considerable difference in degree and nature of their impact.

5.
Clin Spine Surg ; 32(10): 417-422, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-30024445

RESUMEN

STUDY DESIGN: Presentation of a surgical technique with accompanying video (Supplemental Digital Content 1, http://links.lww.com/CLINSPINE/A67) of an illustrative case. OBJECTIVE: The objective of this study was to present a helpful and easy-to-implement technique for improving initial referencing accuracy, as well as rereferencing accuracy in cases of multilevel instrumentation or in cases of dislocation of the reference array. SUMMARY OF BACKGROUND DATA: Navigation-assisted spine surgery has become standard of care in most hospitals performing complex spine interventions. Although short-segment instrumentations are fairly straight-forward with current hardware and software solutions, obtaining ideal accuracies and troubleshooting reference array disruptions remain challenging. METHODS: A surgical technique is presented as a step-by-step guide using intraoperative videos and photographs as well as imaging data in an illustrative case of thoracic hemivertebra resection and dorsal instrumentation. TECHNIQUE/RESULTS: After skin incision is performed at the index level, posterior soft tissue preparation is performed. Before firmly attaching the reference array to a spinous process we then insert a minimum of four 5 mm mini screws at any bony structure within the exposure. Then an intraoperative navigation scan (3-dimensional computed tomography or x-ray) is obtained, and initial referencing is performed using the previously inserted mini screws as landmarks. This yields mean accuracies of 1 mm or lower and is easily verifiable by placing the navigation probe on a mini screw head. This action can be swiftly repeated at any time to prevent reduced accuracy because of insertion forces applied during pedicle screw placement. In addition, this allows for easy rereferencing in cases of disruption or complete removal of the navigation array, eliminating the need to perform additional computed tomography or x-ray scans during the procedure. CONCLUSIONS: The technique presented allows for rapid and highly accurate initial referencing and can be used in all cases of navigation-assisted spine surgery. It also allows for hassle-free rereferencing in cases of disruption or accidental removal of the reference array.


Asunto(s)
Tornillos Pediculares , Columna Vertebral/cirugía , Niño , Femenino , Humanos , Cuidados Posoperatorios , Cuidados Preoperatorios , Columna Vertebral/diagnóstico por imagen , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/cirugía , Tomografía Computarizada por Rayos X
6.
J Food Sci Technol ; 55(11): 4600-4607, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30333656

RESUMEN

The leaves of seventeen cultivars of olive growing in the north of Iran were investigated for total phenol content and antioxidant activity. The identification and quantification of main phenolic compounds were performed by reverse phase high performance liquid chromatography with diode array detector. The cultivars Kalamon, Gordal, and Coratina contained the highest concentration of phenolic compounds (190.65 ± 0.03, 184.72 ± 0.001, and 155.91 ± 0.06 mg GAE/g extract, respectively). The maximum radical scavenging activities were found in Gordal, Coratina, and Kalamon extracts (IC50 20.66, 22.95, and 26.74 µg ml-1, respectively). The extracts of Mishen, Fishomi, and Arbequina (1971.37 ± 0.007, 1794.57 ± 0.001, and 1760.57 ± 0.005 µmol Fe II/g dried extract, respectively) showed highest antioxidant activity in FRAP assay. The identification analysis demonstrated the present of vanillin, rutin, luteolin 7-O-glucoside, oleuropein, and quercetin. The highest oleuropein concentrations were detected in cultivars Mishen, Beleidi, Kalamon, and Roghani while it was not detected in cultivars Conservolea, Amigdalolia, Leccino, and Fishomi.

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