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1.
ACS Omega ; 5(7): 3346-3357, 2020 Feb 25.
Article in English | MEDLINE | ID: mdl-32118149

ABSTRACT

Parabens are widely used as preservatives in food, pharmaceutical, and cosmetic products. These compounds are known for their estrogen agonist activity. This research investigates the synthesis of micro- and mesoporous silica from coal fly ash at different pH values (13, 11, 9, and 7) as well as its use as an adsorbent for the removal of parabens. The materials were characterized, and X-ray fluorescence (XRF) analysis revealed that the fly ash acid treatment reduced the presence of aluminum, iron, and calcium oxides and also that silica synthesized at lower pH values (7 and 9) showed a higher SiO2 content. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses revealed microporous silica formation for silica synthesized at pH 13 and mesoporous silica at pH 7, 9, and 11. Adsorption tests were performed with materials, and FA-AT7 showed a higher adsorption capacity. The effect of factors (A) adsorbent mass, (B) initial paraben concentration, and (C) agitation rate on the adsorption process was studied for the FA-AT7 adsorbent using a factorial experimental design. Standardized Pareto charts revealed a negative effect of factor A, positive effect of factor B, and negative interaction effects of factors A-B for all studied parabens. Isotherms and multicomponent kinetic studies were performed. A linear type-III isotherm was obtained, and adsorption equilibrium was reached at approximately 10 min.

2.
J Forensic Sci ; 61(4): 1074-9, 2016 07.
Article in English | MEDLINE | ID: mdl-27364290

ABSTRACT

The increased marketing of fake perfumes has encouraged us to investigate how to identify such products by their chemical characteristics and multivariate analysis. The aim of this study was to present an alternative approach to distinguish original from fake perfumes by means of the investigation of sodium, potassium, chloride ions, and ethanol contents by chemometric tools. For this, 50 perfumes were used (25 original and 25 counterfeit) for the analysis of ions (ion chromatography) and ethanol (gas chromatography). The results demonstrated that the fake perfume had low levels of ethanol and high levels of chloride compared to the original product. The data were treated by chemometric tools such as principal component analysis and linear discriminant analysis. This study proved that the analysis of ethanol is an effective method of distinguishing original from the fake products, and it may potentially be used to assist legal authorities in such cases.

3.
Neurology ; 69(2): 196-9, 2007 Jul 10.
Article in English | MEDLINE | ID: mdl-17620553

ABSTRACT

We sought to determine if Chamorro individuals with a family history of Guam dementia (GD) or Parkinson dementia complex (PDC) exhibit presymptomatic brain MRI changes. Sixty-six Chamorro subjects had neurocognitive assessment and volumetric MRI. MRI brain volumes differed between diagnostic groups (GD, PDC, control) and according to family history. Chamorros with a family history of PDC or dementia may have increased brain atrophy, suggesting a hereditary susceptibility to neurodegenerative disorders.


Subject(s)
Aging/pathology , Amyotrophic Lateral Sclerosis/pathology , Brain/pathology , Dementia/pathology , Parkinsonian Disorders/pathology , Adult , Age Factors , Aged , Aged, 80 and over , Amyotrophic Lateral Sclerosis/ethnology , Amyotrophic Lateral Sclerosis/physiopathology , Atrophy/ethnology , Atrophy/pathology , Atrophy/physiopathology , Cohort Studies , Dementia/ethnology , Dementia/physiopathology , Disease Progression , Female , Guam/ethnology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Parkinsonian Disorders/ethnology , Parkinsonian Disorders/physiopathology , Predictive Value of Tests , Prognosis
4.
Neurology ; 68(21): 1772-81, 2007 May 22.
Article in English | MEDLINE | ID: mdl-17515539

ABSTRACT

OBJECTIVES: To estimate the prevalence of dementia and its clinical subtypes among Chamorros on Guam aged 65 years or older and to examine associations with age, gender, education, and APOE genotype. BACKGROUND: Chamorros, the indigenous people of Guam, had a high incidence of ALS and parkinsonism-dementia complex (PDC), in the 1950s. Over the next 50 years, ALS incidence declined markedly, but PDC only slightly. The prevalence of late life dementia in Chamorros and its relationship to ALS/PDC are unknown. METHODS: Island-wide population-based survey of Chamorros aged 65 years or older as of January 1, 2003. Two-stage assessment: cognitive and motor screening, followed by neurologic and psychometric evaluation. Data were reviewed at consensus conference to make clinical diagnoses. RESULTS: Of 2,789 Chamorros aged 65 years or older, 73% were enrolled; 27% declined participation, died before contact or screening, or moved off Guam. The point prevalence of all-cause dementia on February 1, 2004, was 12.2%. Prevalence data for subtypes were as follows: Guam dementia (clinically equivalent to AD), 8.8%; PDC, 1.5%; pure vascular dementia, 1.3%; other, 0.6%. The prevalence of dementia rose exponentially with age. Low education was significantly associated with dementia, but gender was not. There was a trend toward higher PDC prevalence among men. The APOE epsilon4 allele was not associated with dementia. CONCLUSIONS: The prevalence of dementia among elderly Chamorros is relatively high. Guam dementia is the most common diagnosis and exceeds parkinsonism-dementia complex. Age and low education are strongly associated with dementia, but gender and APOE epsilon4 are not. Incidence studies will allow risk factors for dementia to be clarified.


Subject(s)
Apolipoproteins E/genetics , Dementia/ethnology , Dementia/genetics , Genetic Predisposition to Disease/genetics , Age Distribution , Aged , Amyotrophic Lateral Sclerosis/ethnology , Amyotrophic Lateral Sclerosis/genetics , Cross-Sectional Studies , DNA Mutational Analysis , Educational Status , Female , Genetic Testing , Genotype , Guam/epidemiology , Humans , Male , Native Hawaiian or Other Pacific Islander/genetics , Neurologic Examination , Neuropsychological Tests , Parkinsonian Disorders/ethnology , Parkinsonian Disorders/genetics , Prevalence , Sex Distribution
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