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1.
Sci Rep ; 14(1): 10399, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710723

RESUMEN

Emissions of ultrafine particles (UFPs; diameter < 100 nm) are strongly associated with traffic-related emissions and are a growing global concern in urban environments. The aim of this study was to investigate the variations of particle number concentration (PNC) with a diameter > 10 nm at nine stations and understand the major sources of UFPs (primary vs. secondary) in Tehran megacity. The study was carried out in Tehran in 2020. NOx and PNC were reported from a total of nine urban site locations in Tehran and BC concentrations were examined at two monitoring stations. Data from all stations showed diurnal changes with peak morning and evening rush hours. The hourly PNC was correlated with NOx. PNCs in Tehran were higher compared to those of many cities reported in the literature. The highest concentrations were at District 19 station (traffic) and the lowest was at Punak station (residential) such that the average PNC varied from 8.4 × 103 to 5.7 × 104 cm-3. In Ray and Sharif stations, the average contributions of primary and secondary sources of PNC were 67 and 33%, respectively. Overall, we conclude that a decrease in primary emission leads to a decrease in the total concentration of aerosols, despite an increase in the formation of new particles by photo nucleation.

2.
Sci Rep ; 13(1): 11763, 2023 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-37474604

RESUMEN

Older people spend most of their time indoors. Limited evidence demonstrates that exposure to indoor air pollutants might be related to chronic complications. This study aimed to estimate the correlation between household air pollution (HAP)'s long-term exposure and the prevalence of elevated hypertension, diabetes mellitus (DM), obesity, and low-density lipoprotein (LDL) cholesterol. From the Global Burden disease dataset, we extracted HAP, hypertension, DM, body mass index, and LDL cholesterol data from Iran from 1990 to 2019 to males and females in people over 50 years. We present APC and AAPC and their confidence intervals using Joinpoint Software statistical software. R software examined the correlation between HAP and hypertension, DM2, Obesity, and high LDL cholesterol. Our finding showed a significant and positive correlation between HAP exposure and prevalence of high low-density lipoprotein cholesterol (p ≤ 0.001, r = 0.70), high systolic blood pressure (p ≤ 0.001, r = 0.63), and high body mass index (p ≤ 0.001, r = 0.57), and DM2 (p ≤ 0.001, r = 0.38). The analysis results also illustrated a positive correlation between indoor air pollution and smoking (p ≤ 0.001, r = 0.92). HAP exposure might be a risk factor for elevated blood pressure, DM, obesity, and LDL cholesterol and, consequently, more serious health problems. According to our results, smoking is one of the sources of HAP. However, ecological studies cannot fully support causal relationships, and this article deals only with Iran. Our findings should be corroborated in personal exposure and biomonitoring approach studies.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminación del Aire , Hipertensión , Masculino , Femenino , Humanos , Anciano , LDL-Colesterol , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Contaminación del Aire Interior/efectos adversos , Contaminación del Aire Interior/análisis , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Hipertensión/epidemiología , Hipertensión/etiología , Colesterol/análisis , Obesidad , Culinaria , Material Particulado/análisis
3.
Talanta ; 238(Pt 1): 123031, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34857349

RESUMEN

In this work, gel electro-membrane extraction (G-EME) combined with flame atomic absorption spectrometry (FAAS) was used for the determination of zinc ions (Zn2+) in water samples. For the first time, the effect of the presence of three types of complexing agents such as phenanthroline (Phen), crown ethers (12C4, 15C5, 18C6), and ethylene-diamine-tetra-acetic acid (EDTA) on the extraction efficiency of zinc ions was studied. In addition, the electroendosmosis (EEO) flow as an unwanted actuator was monitored in the presence and absence of complexing agents. By applying 50 V electrical potential across the membrane, the positive charged Zn2+ ions were migrated from a donor phase (pH 5.0) through the agarose gel membrane (pH 5.0, containing a complexing agent) into the acceptor phase (pH 3.0). The obtained results showed that the highest extraction recoveries were obtained when crown ethers, especially 1% (w/v) 18C6 was added to the gel membrane. In addition, EEO flow was decreased in the presence of all complexing agents (except EDTA), probably due to the increase in electrical resistance. Using the optimum conditions, the limit of detection (LOD), the limit of quantification (LOQ), and extraction recovery% (ER%) were 5.0 µg L-1, 15.0 µg L-1, and 92.5%, respectively. In the end, the applicability of the developed approach was successfully evaluated to determine Zn2+ in tap, mineral, and river water samples.


Asunto(s)
Agua Dulce , Zinc , Concentración de Iones de Hidrógeno , Iones , Espectrofotometría Atómica , Agua
4.
J Environ Health Sci Eng ; 19(2): 1681-1700, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34900298

RESUMEN

Stabilization ponds are open pools that remove total suspended solids, organic matters, microbial and pathogenic agents using physical, chemical, and biological processes. If the stabilization ponds are not well designed, they can produce odors, breed many insects, increase suspended solids concentration in the effluent and pollute groundwater. Consideration of environmental factors is critical for operation and maintenance. In this study, first, information on wastewater treatment plants and meteorological parameters were collected, and simultaneously, specialists were selected to score the effect of environmental factors on stabilization pond efficiency. A geographic information system was used to sit for suitable locations for stabilization ponds. The results showed that 23.6 % of Iran's treatment plants are stabilization ponds, which based on climate, evaporation, sunny hours, ice days, wind speed, and temperature parameters, 33.33 %, 37.3 %, 14 %, 50 %, 64 and 26 % of the stabilization ponds have obtained good points, respectively. The results also showed that 50 % of the stabilization ponds obtained an acceptable score considering all environmental parameters' simultaneous effect. A preliminary study based on considering all the environmental parameters showed that the central and southern regions are the best areas for establishing waste stabilization ponds; in contrast, northern and northeastern regions can have high operation and maintenance costs with lower efficiency. This study has shown that setup and design of the new waste stabilization ponds in Iran need to take into account by considering environmental factors because these factors have the main effect on algae growth which are one of main biological treatment.

5.
J Environ Health Sci Eng ; 19(1): 573-584, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33643658

RESUMEN

This study aimed to identifying the presence of SARS-CoV-2 RNA in raw and treated wastewater during the COVID-19 outbreak in Tehran, Qom and Anzali cities (Iran). From three wastewater treatment plants (WWTPs), 28 treated and untreated wastewater composite samples were collected from April 4 to May 2, 2020. In this study, polyethylene glycol 6000 (PEG 6000) was used through one-step real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) for identification of RNA viruses. SARS-CoV-2 RNA was elicited from wastewater composite samples in all inlet samples taken from the three above mentioned cities. The results of outlet samples were as follows: 1) Results from Qom and East Anzali outlets showed no trace of SARS-CoV-2 RNA despite the difference in treatment disinfection method used (chlorine vs. ultraviolet (UV) disinfection). 2. In Tehran, SARS-CoV-2 RNA was not detected in any of the outlet samples taken from the modules disinfected by UV. Out of the four samples taken from the modules disinfected by chlorine, two were positive for the SARS-CoV-2 RNA which could have been caused by deficiencies in operation and maintenance. It can be concluded that meeting the standards of operation and maintenance (O&M) in WWTPs can considerably ensure that wastewater does not act as one of the roots of transmission for the disease.

6.
J Bioenerg Biomembr ; 52(2): 103-111, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31960257

RESUMEN

Cancer cells apply the Warburg pathway to meet their increased metabolic demands caused by their rapid growth and proliferation and also creates an acidic environment to promote cancer cell invasion. 3-bromopyruvate (3-BrP) as an anti-cancer agent disrupts glycolytic pathway. Moreover, one of the mechanism of actions of Methyl Jasmonate (MJ) is interference in glycolysis. Hence, the aim of this study was to evaluate MJ and 3-BrP interaction. MTT assay was used to determine IC50 and synergistic concentrations. Combination index was applied to evaluate the drug- drug interaction. Human tumor xenograft breast cancer mice was used to evaluate drug efficacy in vivo. Tumor size was considered as a drug efficacy criterion. In addition to drug efficacy, probable side effects of these drugs including hepatotoxicity, renal failure, immunotoxicity, and losing weight were evaluated. Serum alanine aminotransferase and aspartate aminotransferase for hepatotoxicity, serum urea and creatinine level for the possibility of renal failure and changes in body weight were measured to evaluate drug toxicity. IL10 and TGFß secretion in supernatant of isolated splenocytes from treated mice were assessed to check immunotoxicity. 3-BrP synergistically augmented the efficacy of MJ in the specific concentrations. This polytherapy was more effective than monotherapy of 3-BrP, MJ, and also surprisingly cyclophosphamide as a routine treatment for breast cancer in the tumor bearing mice. These results have been shown by decrease in tumor volume and increase of tumor growth inhibition percentage. This combination therapy didn't have any noticeable side effects on kidney, liver, and immune system and body weight.


Asunto(s)
Acetatos/uso terapéutico , Marcadores de Afinidad/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Ciclopentanos/uso terapéutico , Oxilipinas/uso terapéutico , Reguladores del Crecimiento de las Plantas/química , Piruvatos/uso terapéutico , Acetatos/farmacología , Marcadores de Afinidad/farmacología , Animales , Línea Celular Tumoral , Proliferación Celular , Ciclopentanos/farmacología , Modelos Animales de Enfermedad , Femenino , Ratones , Oxilipinas/farmacología , Piruvatos/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Turk J Obstet Gynecol ; 15(2): 80-86, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29971183

RESUMEN

OBJECTIVE: Visfatin is an adipocytokine that functions as an enzyme and a growth factor to investigate the relationship between serum visfatin and the fetus's anthropometric markers up to a year after birth. MATERIALS AND METHODS: Forty-one eligible pregnant women in their first trimester were divided and matched in terms of body mass index (BMI) before pregnancy into normal and higher than normal BMI groups, A and B. Serum visfatin levels were measured during 6-12 and 15-20 weeks of gestation using ELISA. RESULTS: The infants were followed up for a mean duration of 10.19±2.83 months. In group A, there was a strong positive relationship between birth head circumference and the first (p1=0.054, r1=0.580) and second trimester visfatin levels (p2=0.051, r2=0.530). In group B, second trimester visfatin levels correlated negatively with birth length (p=0.015, r=-0.523) and infant's head circumference (p2=0.050, r2=-0.392). In a separate study on group B, visfatin levels in the first and second trimesters showed a significant negative correlation with infant's weight. A significant correlation was observed between the first and second trimesters visfatin level with infant's height in both groups, such that this relationship was positive in group A and negative in group B. Linear regression analysis revealed that first and second trimester visfatin levels were significant independent predictors of infant's weight in group B and infant's height in both groups. Second trimester visfatin level was a significant predictor of birth height in group B. CONCLUSION: Maternal serum visfatin level shows a relationship with fetal and infant anthropometric indicators, with different effects in the two groups, suggesting visfatin dysfunction in the overweight group before pregnancy.

8.
Carbohydr Polym ; 175: 409-416, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28917883

RESUMEN

A cellulose-based nanobiocomposite decorated with Fe3O4 nanoparticles was prepared, characterized and applied as an easily recoverable and reusable green nanocatalyst in the synthesis of pyrano[2,3-d]pyrimidine derivatives in water at room temperature. The characterization was performed by using a variety of conventional analytical instruments such as Fourier transform infrared spectra (FT-IR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX), vibrating sample magnetometer (VSM), thermal analysis (TGA/DTA) and inductively coupled plasma atomic emission spectroscopy (ICP-AES) analyses. Two series of pyranopyrimidine and pyrazolopyranopyrimidines derivatives were synthesized by using the present cellulose-based nanocomposite. This protocol has valuable features like high yield of the products, short reaction times, mild conditions and easy work-up procedure. In addition, the catalyst can be prepared easily with cheap and green starting materials.

9.
Pharm Biol ; 51(2): 246-52, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23126238

RESUMEN

CONTEXT: Artemisia spicigera C. Koch (Asteraceae) is a perennial shrubby herb and is generally distributed in Armenia, Iran, and Middle Anatolia. This species traditionally has been used in medicines. OBJECTIVE: The aim of this research is to study the chemical composition and antibacterial activity of essential oils from Artemisia spicigera populations in northwest of Iran. MATERIALS AND METHODS: The essential oil of A. spicigera was obtained by hydrodistillation from eight populations collected from different regions of East Azerbaijan and West Azerbaijan provinces (Iran) and analyzed by gas chromatography-mass spectrometry (GC-MS). The antibacterial activity of the oils was investigated against four Gram-positive and four Gram-negative bacteria using MIC determinations and the agar-gel diffusion method. RESULTS: Fourteen compounds were identified as the main components of the essential oils and the most abundant constituents are 1,8-cineole, camphor, α-thujone, camphene, ß-thujone and p-cymene. Essential oil of population No. 1 showed the highest activity against Escherichia coli, Enterobacter aerogenes, Serratia marcescens and Staphylococcus aureus but the highest activity against St. saprophyticus, Bacillus megaterium, and B. cereus was found with population No. 6 and for Citrobacter amalonaficus with population No. 5. MIC values of essential oils ranged from 6 µg/mL against Bacillus megaterium to 12 µg/mL against Citrobacter amalonaficus. DISCUSSION: This study demonstrates the occurrence of 1,8-cineole/camphor/camphene chemotype of A. spicigera but there is also significant chemical variation between the studied populations. The findings showed the studied oils have good antibacterial activity, and thus potential to be used as natural health products.


Asunto(s)
Antibacterianos/farmacología , Artemisia/química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Antibacterianos/análisis , Antibacterianos/aislamiento & purificación , Monoterpenos Bicíclicos , Alcanfor/farmacología , Ciclohexanoles/farmacología , Pruebas Antimicrobianas de Difusión por Disco , Destilación , Eucaliptol , Cromatografía de Gases y Espectrometría de Masas , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/crecimiento & desarrollo , Irán , Pruebas de Sensibilidad Microbiana , Monoterpenos/farmacología , Aceites Volátiles/análisis , Aceites Volátiles/aislamiento & purificación , Componentes Aéreos de las Plantas , Aceites de Plantas/análisis , Aceites de Plantas/aislamiento & purificación , Plantas Medicinales , Terpenos/farmacología
10.
J Hazard Mater ; 190(1-3): 119-24, 2011 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-21531074

RESUMEN

The performance of an electrocoagulation (EC) process with aluminum/iron electrodes for removal of chromium on laboratory scale was studied. The effect of operational parameters such as initial pH, current density (CD), reaction time, initial concentrations (50, 100, 500, 1000 mg/L), solution conductivity, electrical energy consumption (EEC) and type of circuit were studied in an attempt to reach higher Cr(VI) removal efficiency. Alternating pulse current (APC) was used to prevent the passivity or polarization of electrodes. Important operating parameters were optimized to access higher (99%) Cr(VI) removal efficiency as follows: EEC range: 4-58 kW h/m(3) wastewater, CD: 56-222 A/m(2), operating time: 20-110 min, pH 3-9 (pH(optimum) 5), voltage: 15-25 V. NaCl, KCl, PAC (poly aluminum chloride), NaNO(3) were used as supporting electrolytes. NaCl as well as KCl handled the EC with the best performance in every aspect; however, PAC and NaNO(3) did not have the same results (Applied conductivity is better than literature). The results of this work are comparable with those of recent studies. Equal removal efficiency was obtained in "direct current" (DC) and (APC); however, when "APC" was used, water recovery (0.92 m(3)/m(3) wastewater) was significant and the turbidity was 1 NTU. "APC" amazed our experimental team.


Asunto(s)
Cromo/química , Técnicas Electroquímicas/métodos , Contaminantes Químicos del Agua/química , Conductividad Eléctrica , Electricidad , Electrodos , Concentración de Iones de Hidrógeno , Purificación del Agua/métodos
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