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1.
Br J Neurosurg ; 37(5): 1031-1039, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33263433

RESUMEN

OBJECTIVE: To determine the border of glial tumors by diffusion weighted imaging (DWI), apparent diffusion co-efficient (ADC), magnetic resonance spectroscopy (MRS) and perfusion brain MRI. PATIENTS AND METHODS: Ten patients with brain gliomas were enrolled [mean age: 35.3 ± 13.2, range: 20-62]. Conventional MRI was performed for all patients. Besides, tumor mapping based on Choline (Cho)/Creatine (Cr) color map in MRS, perfusion and diffusion color maps, were gathered. Different tumoral and peritumoral regions [normal tissue, reactive edema, infiltrative edema, and tumor core] were defined. MRI criteria were evaluated in areas targeted for biopsy and histopathologic evaluation was determined. RESULTS: Tumor cell positive samples [one necrosis, 26 infiltrative and nine tumor cores] composed 36 (75%) of the 48 samples. Seven (19.4%) of the positive samples were interpreted as not tumor on MRI. Five were identified as reactive edema and two as normal tissue] [kappa: .67, p-value < .001]. Mean of ADC, median of N-acetylaspartate (NAA) and NAA/Cho were statistically different between positive and negative samples (p = .02 and p < .001, respectively). Mean ADC and median Cho/NAA were statistically different in missed tumor containing tissue presented as reactive edema compared to normal and correctly diagnosed reactive edema samples together (p-values < .05). CONCLUSIONS: Multimodal MRI could define infiltrated borders of brain gliomas.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Glioma/complicaciones , Glioma/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Edema/diagnóstico por imagen , Edema/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología
2.
Environ Monit Assess ; 195(4): 464, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36914842

RESUMEN

Three coastal lagoons on the Sefidrud Delta, Caspian Sea, were investigated to evaluate heavy metal pollution in sediments. Amirkola Lagoon is located in the eastern part of the delta (abandoned delta lobe) and is aged more than 500 years, whereas Kiashahr and Zibakenar lagoons are in the western or active part delta lobe and formed in the last decades. One hundred six sediment samples and three sediment cores were taken from studied lagoons. The samples were analyzed by ICP-OES. Geo-accumulation index (Igeo), contamination factor (CF), degree of contamination (Cdeg), pollution load index (PLI), and Potential ecological risk index (RI) were employed to determine heavy metal pollution for Co, Cr, Cu, Ni, Pb, V and Zn. Nonparametric statistical analysis (Two-step cluster analysis, analysis of variance, and T-test technique) was used to discriminate the pollution sources. Based on contamination indices, the Kiashahr and Zibakenar lagoons show significant to moderate contamination with Co, Cu, Pb, Zn, and V, whereas the Amirkola Lagoon samples show the lowest metal contamination. PLI values demonstrated metal contamination in the Kiashahr and Zibakenar lagoons but no contamination in the Amirkola Lagoon. Although there was a notable rise in RI values from Amirkola to two other lagoons, all indicated low ecological risk. Statistical methods designated the unique interpretation of contaminant sources. Although the same geogenic origin of sediments in the Sefidrud Delta and lagoons deposits, Co, Zn, and Pb show anthropogenic sources in the newly-formed Kiashahr and Zibakenar lagoons.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Mar Caspio , Irán , Plomo/análisis , Contaminantes Químicos del Agua/análisis , Sedimentos Geológicos , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Medición de Riesgo
3.
Environ Monit Assess ; 187(12): 727, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26545371

RESUMEN

In this study, 28 groundwater and 13 soil samples from Ahangaran mining district in Hamedan Province, west of Iran were collected to evaluate the level of contamination. Average concentrations of As, Cu, Pb, Zn, Mn, Sb, and Ni in groundwater samples were 1.39, 3.73, 2.18, 9.37, 2.35, 4.44, and 5.50 µg/L (wet season), and 11.64, 4.92, 4.32, 14.77, 5.43, 4.12, and 0.98 µg/L (dry season), respectively. Results of groundwater samples analysis showed that the average of analyzed metals in the wet and dry seasons were below the permissible limits, except As in the dry season which displays concentrations that exceed US EPA water quality criteria recommended for drinking water. Also, the heavy metal pollution index (HPI) values in each sampling station were less than the critical index limit and were suitable for drinking. Factor analysis revealed that variables influential to groundwater quality in one season may not be as important in another season. Average concentrations of Ag, As, Cd, Cu, Pb, Sb, and Zn in soil samples were 2.61, 31.44, 0.51, 55.90, 1284.9, 21.26, and 156.04 mg kg(-1), respectively. The results of the geoaccumulation index (I geo) showed the following decreasing order: Pb > Zn > Cu > As > Sb > Cd > Ag. Potential ecological risk index (RI) suggests that the contamination in the investigated area is moderate to very high risk and the ranking of the contaminants in decreasing order is Ag > Sb > Pb > Cd > As > Cu > Zn.


Asunto(s)
Monitoreo del Ambiente , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Ambiental/análisis , Contaminación Ambiental/estadística & datos numéricos , Agua Subterránea/química , Irán , Minería , Estaciones del Año , Suelo/química
4.
Mar Pollut Bull ; 121(1-2): 381-389, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28622992

RESUMEN

Understanding the anthropogenic effects on the Sefidrud delta, the concentration of six metals (Cr, Co, Cu, Ni, Pb and Zn) was measured in two sites included the old Sefidrud delta (Amirabad, 23 samples) and the new Sefidrud delta (Kiashahr, 24 samples). Geoaccumulation Index (Igeo), Enrichment Factor (EF), Contamination Factor (CF) and Pollution Load Index (PLI) were used to determine the metal pollution in all sediment samples. Although the EF, Igeo, CF and PLI results in the old delta indicate no significant pollution, sediment samples in the new delta show a considerable pollution. Since the sediment source and the lithology of the Sefidrud River drainage basin did not change in the past 500years, the metal pollution in the new delta must be from anthropogenic sources.


Asunto(s)
Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Sedimentos Geológicos , Irán
5.
Arch Iran Med ; 18(7): 435-40, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26161708

RESUMEN

BACKGROUND: Many studies have shown that active vitamin A derivatives suppress the formation of pathogenic T cells in multiple sclerosis (MS) patients. The aim of the present study is to determine the impact of vitamin A on disease progression in MS patients. METHODS: A total of 101 relapsing-remitting MS (RRMS) patients were enrolled in a 1-year placebo-controlled randomized clinical trial. The treated group received 25000 IU/d retinyl palmitate for six month followed by 10000 IU/d retinyl palmitate for another six month. The results of the expanded disability status scale (EDSS) and multiple sclerosis functional composite (MSFC) were recorded at the beginning and the end of the study. The relapse rate was recorded during the intervention. Patients underwent baseline and follow up brain MRIs. RESULTS: The results showed "Mean ± SD" of MSFC changes in the treated group was (-0.14 ± 0.20) and in the placebo group was (-0.31 ± 0.19). MSFC was improved significantly (P < 0.001) in the treatment group. There were no significant differences between the "Mean ± SD" of EDSS changes in the treated (0.07 ± 0.23) and placebo (0.08 ± 0.23) groups (P = 0.73). There were also no significant differences between the "Mean ± SD" of annualized relapse rate in the treated group (-0.36 ± 0.56) and placebo (-0.53 ± 0.55) groups (P = 0.20). The "Mean ± SD" of enhanced lesions in the treatment (0.4 ± 1.0) and in the placebo (0.2 ± 0.6) groups were not significantly different (P = 0.26). Volume of T2 hyperintense lesions "Mean ± SD" was not significantly different between treatment (45 ± 137) and placebo (23 ± 112) groups after intervention (P = 0.23). CONCLUSION: Vitamin A improved total MSFC score in RRMS patients, but it did not change EDSS, relapse rate and brain active lesions.


Asunto(s)
Progresión de la Enfermedad , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Vitamina A/análogos & derivados , Adulto , Evaluación de la Discapacidad , Diterpenos , Método Doble Ciego , Femenino , Humanos , Irán , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Ésteres de Retinilo , Resultado del Tratamiento , Vitamina A/administración & dosificación , Adulto Joven
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