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1.
Ecotoxicol Environ Saf ; 212: 111986, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33540338

RESUMEN

Population exposure to environmental contaminants can be precisely observed through human biomonitoring studies. The present study aimed to systematically review all the biomonitoring studies conducted in Iran on some selected carcinogen environmental pollutants. In this systematic review study, 11 carcinogen agents were selected including arsenic, cadmium, chromium, nickel, lindane, benzene, trichloroethylene (TCE), pentachlorophenol (PCP), radon-222, radium-224, - 226, - 228, and tobacco smoke. The Web of Science, PubMed, and Scopus databases were searched for peer-reviewed articles published in English. After several screening steps, data were extracted from the studies. Meta-analyses (a random-effect model using the DerSimonian-Laired method) were performed only for the biomarkers with more than three eligible articles, including cadmium in blood and breast milk, and arsenic in breast milk. Methodological quality of the studies was assessed using the Newcastle-Ottawa Quality Assessment Scale adapted for cross-sectional studies. Of the 610 articles found in the database search, 30 studies were eligible for qualitative review, and 13 were included in the meta-analysis (cadmium in blood (n = 3), cadmium in breast milk (n = 6), and arsenic in breast milk (n = 4)). The overall pooled average concentrations (95% CI) of cadmium in blood, cadmium in breast milk, and arsenic in breast milk were 0.11 (95% CI: 0.08, 0.14), 5.38 (95% CI: 3.60, 6.96), and 1.42 (95% CI: 1.02, 1.81) µg/L, respectively. These values were compared with the biomarker concentrations in other countries and health-based guideline values. This study showed that there is a need for comprehensive action plans to reduce the exposure of general population to these environmental contaminants.


Asunto(s)
Monitoreo Biológico , Contaminantes Ambientales/análisis , Arsénico/análisis , Cadmio/análisis , Cromo/análisis , Estudios Transversales , Exposición a Riesgos Ambientales/análisis , Contaminación Ambiental/análisis , Femenino , Humanos , Irán , Leche Humana/química , Níquel/análisis
2.
Atmos Pollut Res ; 12(3): 302-306, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33519256

RESUMEN

This study investigated the presence of SARS-CoV-2 in air of public places such as shopping centers, a post office, banks, governmental offices, and public transportation facilities including an airport, subways, and buses in Tehran, Iran. A total of 28 air samples were collected from the eight groups of public and transportation locations. The airborne particle samples were collected on PTFE or glass fiber filters using two types of samplers with flow rates of 40 and 3.5 L/min, respectively. The viral samples were leached and concentrated, and RNA was extracted from each. The presence of viral RNA was evaluated using novel coronavirus nucleic acid diagnostic real time PCR kits. In 64% of the samples, SARS-CoV-2 RNA (62% and 67% from the public places and transportation, respectively) was detected. Positive samples were detected in banks (33%), shopping centers (100%), governmental offices (50%), the airport (80%), subway stations (50%), subway trains (100%), and buses (50%). Logistic regression showed that number of people present during the sampling and the sampled air volume were positively associated with presence of SARS-CoV-2; while the percentage of people with masks, air temperature, and sampling site's volume were negatively related to SARS-CoV-2's presence. However, none of these associations were statistically significant. This study showed that most public places and transportation vehicles were contaminated with SARS-CoV-2. Thus, strategies to control the spread of COVID-19 should include reducing the number of people in indoor spaces, more intense disinfection of transport vehicles, and requiring people to wear masks.

4.
J Environ Sci (China) ; 100: 167-180, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33279029

RESUMEN

The contamination of fish type products such as silver pomfret fish fillets by potentially toxic elements (PTEs) has raised global health concerns. Related studies regarding the concentration of PTEs in fillets of silver pomfret fish were retrieved among some international databases such as Scopus, PubMed and Embase between 1 January 1983 and 10 March 2020. The pooled (mean) concentration of PTEs in fillets of silver pomfret fish was meta-analyzed with the aid of a random-effect model (REM). Also, the non-carcinogenic risk was estimated via calculating the 95th percentile of the total target hazard quotient (TTHQ). The meta-analysis of 21 articles (containing 25 studies or data reports) indicated that the ranking of PTEs in fillets of silver pomfret fish was Fe (11,414.81 µg/kg wet weight, ww) > Zn (6055.72 µg/kg ww) > Cr (1825.79 µg/kg ww) > Pb (1486.44 µg/kg ww) > Se (1053.47 µg/kg ww) > Cd (992.50 µg/kg ww) > Ni (745.23 µg/kg ww) > Cu (669.71 µg/kg ww) > total As (408.24 µg/kg ww) > Co (87.03 µg/kg ww) > methyl Hg (46.58 µg/kg ww). The rank order of health risk assessment by country based on the TTHQ for adult consumers was Malaysia (2.500) > Bangladesh (0.886) > Iran (0.144) > China (0.045) > Pakistan (0.020) > India (0.015), while the corresponding values for child consumers was Malaysia (11.790) > Bangladesh (4.146) > Iran (0.675) > China (0.206) > Pakistan (0.096) > India (0.077). The adult consumers in Malaysia and children in Malaysia and Bangladesh were at considerable non-carcinogenic risk. Therefore, following the recommended control plans in order to reduce the health risk associated with the ingestion of PTEs via consumption of silver pomfret fish fillets is crucial.


Asunto(s)
Metales Pesados , Medición de Riesgo , Plata , Adulto , Animales , Niño , China , Monitoreo del Ambiente , Humanos , India , Irán , Malasia , Metales Pesados/análisis , Pakistán
6.
Heliyon ; 6(1): e03091, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31909262

RESUMEN

The hybrid treatment techniques have been proven that could be a proper solution to the metalworking fluid (MWF) wastewaters disposal challenge. Hence, this investigation was conducted aim to the assessment of chemical addition-dissolved air floatation (CA-DAF) unit followed with a heterogeneous photocatalytic (PC) process as UV/H2O2/ZnO to treat MWF wastewater produced in one of the central industrial estates in the Middle East. The CA-DAF unit was implemented as trial and errors and had an appropriate efficiency. However, the environmental discharge standards were not achieved only by this unit, so that, a PC process considered for this purpose in a pilot-scale reactor. And also, Chemical oxygen demand (COD), total petroleum hydrocarbons (TPHs) were considered as physicochemical parameters to analyze the applied photochemical reaction throughout the concentrations of ZnO and H2O2, and pH value as variables of the study. The ideal and optimized conditions were observed at pH 10, 600 mg l-1 of ZnO, and 13.11 g l-1 of H2O2 via 99.87% and 97.9% reduction rates in total COD and TPH, respectively. These removal rates were obtained for this integrated strategy under the optimized reaction. By evaluating the synergistic effect, it was found that UV/ZnO could be a predominant reaction in this process. The organic and intermediates analysis appeared 78.46% reduction for all detected organic matters. Besides, PC generation of bis phthalate, mono phthalate, benzene, and benzoic acid to 2,6-bis (1,1-dimethylethyl)-4-mthyl phenol was the reason of the residual phenolic compound concentration in the reaction solution with low removal rate. The kinetic study showed that this reaction could be well fitted with the pseudo-first-order kinetic model by R 2 equal with 0.973 and 0.988 in turn for COD and TPH. The expenditures to treat 1 m3 of the CA-DAF was estimated at 5.335 us$ via cost analysis. Finally, the collected findings indicate that CA-DAF integrated with UV/H2O2/ZnO can be an efficient approach in the MWF wastes disposal or treatment for reuse.

7.
Heart Views ; 20(1): 1-5, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31143379

RESUMEN

OBJECTIVES: We studied immediate and midterm results of transcatheter closure of atrial septal defects (ASDs) using the Amplatzer septal device closure. METHODS: The study included one hundred and thirty-seven patients (31 men, 106 women; mean age 8 ± 7.3 years; range 1-65 years) who underwent transcatheter closure of secundum ASD between October 2014 and October 2016 in our center. All the patients were evaluated by transthoracic echocardiography before and during the procedure and in adult patients; transesophageal echocardiography was performed before the procedure. Closure of ASDs was performed under general anesthesia with transthoracic echocardiographic guidance. Follow-up controls were done on the day after procedure, 1 week, 1, 3, 6, and 12 months, and annually thereafter. The median follow-up periods of ASD was 15 months. RESULTS: The mean ASD and device size were 13.5 ± 2.3 and 14.3 ± 3.2 mm, respectively. The mean procedural and fluoroscopy times were 21.3 ± 4.7 and 5.1 ± 1.9 min. Immediate complications such as mortality, bleeding, fatal arrhythmia, and device embolization did not occur in any patient during and after the procedure. Cardiac arrhythmias were seen in 4 patients during the 1st month after the procedure. Late device embolization did not occur during the follow-up. No residual shunts were seen after the procedure. Transient ischemic attack was seen in one patient during the procedure and in one patient 2 days after the procedure without long-term complication. CONCLUSION: Transcatheter closure of ASDs using the Amplatzer devices is an efficacious and safe therapeutic option.

8.
Iran J Pediatr ; 26(5): e5833, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28203338

RESUMEN

BACKGROUND: Information from pulse oximeter waves confirms the presence of a pulse and helps obtain waves from tissue when the supplying artery is not readily accessible. OBJECTIVES: This study determined the predictive value of pulse oximeters for detecting improved arterial pulses after angiography. PATIENTS AND METHODS: This cross-sectional, multi-center study included 467 4-day-old to 12-year-old patients and was conducted from January 2012 to January 2016. Angiographies were performed on 12-year-old or younger children for various medical reasons using venous, arterial, or both types of paths. The posterior malleolar or dorsalis pedis were palpated in punctured lower extremities. In the absence of a pulse, pulse oximetry was performed to identify pulse curves at 1 hour, 6 hours, and 12 hours after each angiography. RESULTS: Pulse oximetry displayed the pulses of 319 patients immediately following each angiography. Of these, 262 patients had palpable pulses at 6 hours after angiography (P < 0.0001), while 57 patients had no palpable pulse. Of these 57 patients, 15 had no palpable pulse at 12 hours after angiography (P < 0.0001). The odds of pulse improvement in children 6 hours after catheter angiography were 76% for the arterial path, 90% for the venous path, and 83.2% for both paths. At 12 hours after catheter angiography, these values increased to 91.6% for the arterial path, 100% for the venous path, and 95.9% for both paths. CONCLUSIONS: The pulse oximeter can display the pulse curve immediately (1 hour) after angiography and indicate pulse improvement at 12 hours maximally following an angiography. In this case, heparin alone may be used instead of thrombolytic agents.

9.
Gen Physiol Biophys ; 27(4): 263-70, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19202199

RESUMEN

The aim of this study was to test the effects of age and long-term exercise training on antioxidant, heat shock protein 70 (HSP70) expression and apoptosis by comparing the hearts of sedentary and trained rats. Training groups went under 3-, 6- and 9-months of regular exercise (25 m/min with a 0% slope, 60 min/day and 6 days/week). Level of glutathione increased with age in trained and sedentary control rats but level of this factor unchanged by training. Activity of mitochondrial superoxide dismutase (mtSOD) increased in heart homogenates of 6- and 9-months trained animals as compared with their sedentary. The rates of apoptosis were increased with age but level of apoptosis in 9-months trained group was significantly lower than corresponding sedentary. Levels of HSP70 expression were significantly decreased with age while long-term training induced marked increase in HSP70 expression levels. These results show that a long-term regular exercise affects age-induced changes in mtSOD, HSP70 and apoptosis as it increases mtSOD activities and HSP70 expression levels and elicits a marked reduction in apoptosis rate in rat myocardium. However, a shorter training program is not effective.


Asunto(s)
Envejecimiento/fisiología , Apoptosis/fisiología , Glutatión/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Miocardio/enzimología , Condicionamiento Físico Animal , Animales , Antioxidantes/metabolismo , Masculino , Ratas , Superóxido Dismutasa/metabolismo
10.
J Sports Sci Med ; 6(2): 243-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-24149335

RESUMEN

This study investigated the onset of age-related changes in the myocardial antioxidant enzymes and apoptosis and the vulnerability of the myocardium to oxidative stress following exercise training. Few studies have investigated the influence of the most prevalent life-prolonging strategy physical exercise, on the age increment alterations in the myocardial antioxidant enzymes and apoptosis at mid age and to determine whether exercise-induced antioxidant defense system could attenuate lipid peroxidation. Thirty six male Wistar rats were randomly assigned to exercise trained (n = 18) and sedentary (n = 18) groups. The rats in the training group went under 12, 24 and 36 weeks of moderate exercise trainings (25 m·min(-1) for 60-min with a 0% slope). Six sedentary controls were killed together with each exercise group at the end of the training programs. Levels of thiobarbituric acid-reactive substances (TBARS) and catalase (CAT) activity in myocardial homogenates were unchanged by training irrespective of the protocol duration. However, an increased content of the TBARS was detected in hearts from both the 24 and 36-week trained and sedentary control rats when compared with their corresponding 12-week groups (p<0.01). The activity of superoxide dismutase (SOD) remained unchanged after the 12-week training period whereas a significant increase was observed in heart homogenates of 24-week trained animals as compared with their sedentary controls (p<0.05). The activity of glutathione peroxidase (GPX) remained unchanged. The rates of apoptosis which was detected by ELISA assays, were significantly modified after 24 and 36-week of training (p<0.05). These results demonstrate that a long-term endurance training (24 weeks) induced increases in SOD activities in rat myocardium and elicited a marked reduction in apoptosis rate. However, a shorter training program (12 weeks) was not effective in increasing heart antioxidant defenses. Key pointsExercise training induces activity of myocardial SOD.Long-term regular moderate-intensity exercise decreases the rate of myocardial apoptosis.Short-term regular moderate-intensity exercises do not change the rate of myocardial anti oxidant capacity and apoptosis.

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