The Relationship between Zinc Levels and Autism: A Systematic Review and Meta-analysis

How to Cite This Article: Babaknejad N, Sayehmiri F, Sayehmiri K, Mohamadkhani A, Bahrami S. The Relationship between Zinc Levelsand Autism: Systematic Review and Meta-analysis. Iran J Child Neurol. Autumn 2016; 10(4):1-9. AbstractObjectiveAutism is a complex behaviorally defined disorder. There is a relationship between zinc (Zn) levels in autistic patients and development of pathogenesis, but the conclusion is not permanent. Materials & MethodsThe present study conducted to estimate this probability using meta-analysis method. In this study, Fixed Effect Model, twelve articles published from 1978 to 2012 were selected by searching Google scholar, PubMed, ISI Web of Science, and Scopus and information were analyzed. I² statistics were calculated to examine heterogeneity. The information was analyzed using R and STATA Ver. 12.2. ResultsThere was no significant statistical difference between hair, nail, and teeth Zn levels between controls and autistic patients: -0.471 [95% confidence interval (95% CI): -1.172 to 0.231]. There was significant statistical difference between plasma Zn concentration and autistic patients besides healthy controls: -0.253 (95% CI: 0.498 to -0.007). Using a Random Effect Model, the overall Integration of data from the two groups was -0.414 (95% CI: -0.878 to -0.051).ConclusionBased on sensitivity analysis, zinc supplements can be used for the nutritional therapy for autistic patients. References1. Arnold LE, Farmer C, Kraemeret HC, et al. Moderators, mediators, and other predictors of Risperidoneresponse in children with Autistic Disorder and Irritability. J Child Adolesc Psychopharmacol 2012; 20(2): 83-92.2. Karimzadeh P. Recent finding about etiology of autism. Rehabilitation 2000; 1(2):58-63.3. 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The Protective Roles of Zinc and Magnesium in Cadmium-Induced Renal Toxicity in Male Wistar Rats

Background: Cadmium (Cd) is a heavy metal that has widespread use. It enters the food chain in different ways, including soil and water. Cadmium can cause dysfunction of different body organs. Zinc (Zn) and magnesium (Mg) supplementation can have protective effects against cadmium toxicity due to their antagonistic and antioxidants properties. This study examines the influence of supplemental Zn and Mg on Cd renal toxicity. Methods: Young male Wistar rats were divided into six groups of five. The Cd group received 1 mg Cd/kg and the control group received 0.5 mg/kg normal saline (i.p.). The other four groups were administered 1 mg/kg Cd+0.5 mg/kg Zn, 1 mg/kg Cd+1.5 mg/kg Zn, 1 mg/kg Cd+ 0.5 mg/kg Mg, and 1 mg/kg Cd+ 1.5 mg/kg Mg (i.p.) for 21 days. Then, serum sodium, potassium, urea, creatinine, and protein levels were measured. Results: The results indicated that creatinine and protein levels decreased while urea, sodium, and potassium levels increased as a result of Cd exposure. Co-administered Cd and Zn and Mg decreased urea and increased sodium serum level in comparison to the cadmium group. Treatment by Mg, contrary to co-administered Cd and Zn, reduced serum protein level compared to the cadmium group. Compared to the cadmium treated group, Zn and Mg treatment enhanced serum creatinine level and reduced serum potassium level. Conclusion: The findings seem to suggest that zinc and magnesium compounds, due to their antagonistic and antioxidant activities, can protect Cd renal toxic effects in a dose-dependent manner

Genotyping of Zoonotic Toxoplasm gondii Isolated from Aborted Fetuses of Ewes of Lorestan Province Based on SAG2، SAG3 and GRA6 Molecular Markers

Background & objectives: Toxoplasma gondii is a zoonotic obligate intracellular protozoan parasite that infects all warm-blooded animals as well as human worldwide. Determining the parasite genotype in intermediate hosts  is crucial in  evaluating the role of these types in human infections as wll as in prevention programs. Therefore, this study aimed to identify and detect the genotypes of Toxoplasma gondii in aborted fetuses of ewes in Lorestan province. Methods: Identification of the parasite was performed  on the brain and liver tissues of 142 aborted fetuses using  a conventional PCR based on amplification of highly repetitive 529 bp region of the parasite genome. Genotyping of positive samples, which were isolated from the brain and liver, was performed by PCR-RFLP based on SAG2, SAG3 and GRA6 molecular markers. Results: From a total of 142 samples  obtained from  brain  and fetus, 10 cases (7%) were determined as positive samples based on conventional PCR. The precence of parasite DNA was also confirmed in the liver of  3 positive samples. Evaluation of RFLP pattern of amplified SAG2, SAG3 and GRA6 genes showed the presence of various types of parasites, incuding type I in 3 samples, type II in 2 samples and atypical type in 5 samples. Conclusion: Isolation of types I, II and atypical type of T. gondii from ewes in  Lorestan province suggests the need for greater attention to parasite transmission from livestock to human, particularly in pregnant women and people with weakened immune system

Evaluation and analysis of gaseous emission in landfill area and estimation of its pollutants dispersion, (case of Rodan in Hormozgan, Iran)

Background: The biogases are the mixture of gases produced through the microbial decomposition of organic waste which are amply observed in the landfills. The main purpose of this study was to estimate the emission rates of landfill gases such as carbon dioxide, methane and non-methane organic compounds (NMOCs) in the solid waste landfill of Rodan city in Hormozgan province. Methods: All the necessary information such as population, geographic and climate of Rodan city were collected. Solid waste analysis was then conducted. Afterward, the LandGEM software is used in this study for the purpose of estimation of total biogas, methane, carbon dioxide and NMOCs emission from Rodan’s landfill. Results: The analysis of results showed that only 24.18% of the produced waste in this city is perishable. The calculations indicate that the peak of biogas production which is equal to 420 tons per year would be achieved in the year 2019. The production rates of carbon dioxide and methane in the same year would be equal to 308 and 112 tons per year respectively. The pollutants transmittance calculations in the vicinity of the landfill revealed that the maximum pollutant concentration is within the maximum distance of 200 m. Conclusion: The results obtained in this study could be used for the purpose of design and installation of extraction or incineration equipment in the landfill of Rodan