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81.
Mahdieh Abbasalizad Farhangi Seyyed Ali Keshavarz Mohammadreza Eshraghian Alireza Ostadrahimi 《Journal of the American College of Nutrition》2013,32(4):268-274
Objective: Vitamin A and its retinoid derivates play an important role in regulation of normal growth and development. Vitamin A has been shown to regulate thyroid hormone metabolism and inhibit thyroid-stimulating hormone (TSH) secretion via down regulation of TSH-β gene expression; however, the effect of vitamin A on thyroid function in obese individuals who are at higher risk of subclinical hypothyroidism is still unclear. In the present study we investigate the impact of vitamin A supplementation on thyroid function in obese women.Method: A 4-month randomized, double blind controlled trial was conducted among 84 healthy women aged 17–50 years old: 56 were obese (body mass index [BMI] 30–35 kg/m2) and 28 were nonobese (BMI 18.5–24.9 kg/m2). Obese women were randomly allocated to receive either vitamin A (25,000 IU/d retinyl palmitate) or placebo. Nonobese women received vitamin A. At baseline and 4 months after intervention, serum concentrations of TSH, total thyroxine (T4), total triiodothyronine (T3), retinol-binding protein (RBP), and transthyretin (TTR) were measured.Results: Baseline concentrations of thyroid hormones, RBP and TTR were not significantly different between groups. Vitamin A caused a significant reduction in serum TSH concentrations in obese (p = 0.004) and nonobese (p = 0.001) groups. Serum T3 concentrations also increased in both obese and nonobese vitamin A–treated groups (p < 0.001). Serum T4 decreased in all 3 groups after treatment. The results showed a significant reduction in serum RBP in the obese group after vitamin A supplementation (p = 0.007), but no significant change was seen in serum TTR.Conclusions: Serum TSH concentrations in vitamin A–treated subjects were significantly reduced; therefore, vitamin A supplementation might reduce the risk of subclinical hypothyroidism in premenopausal women. 相似文献
82.
Purpose:?To investigate the effects of γ-rays on male NMRI mice, in the absence or presence of vitamin E, on abnormalities in chromosome number in 8-cell embryos generated after mating with non-irradiated female mice.Materials and methods:?The 8 – 11 week old male NMRI mice were irradiated whole body with 4 Gy of γ-rays alone or in combination with 200 international units (IU)/kg vitamin E administered 1 h prior to irradiation. After 4 days, they were mated at weekly intervals with superovulated, non-irradiated female mice in successive 6 weekly periods. About 68 h post coitous (p.c.), 8-cell embryos were fixed on slides using standard methods in order to screen for abnormalities in chromosome number.Results:?In control embryos, 8% of metaphases were aneuploid whereas in embryos generated from irradiated mice, the frequency of aneuploidy increased dramatically at all post irradiation sampling times (p < 0.001). Administration of vitamin E one hour before irradiation, significantly decreased chromosomal aberrations in all 6 groups (p < 0.05).Conclusion:?Data indicate that γ-irradiation affects spermatogenesis and causes DNA alterations in sperm that may lead to chromosome abnormalities in subsequent embryos. Administration of vitamin E before irradiation effectively reduced the frequency of chromosomal abnormalities. The mechanism(s) by which vitamin E reduces genotoxic effects of radiation could be via radical scavenging or antioxidative effects. 相似文献
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84.
Hallux valgus or the lateral deviation of the great toe is a complex disease. If it is not treated, it will cause the deviation of other toes. Hallux valgus is three times more common in females and may cause uncomfortable deformity of the foot, problems in putting on unsuitable and narrow toe box shoes, and pain on the medial side of the first metatarsophalangeal joint; therefore, patients seek medical services. Untreated hallux valgus may cause the hammer toe deformity of the second toe. In this cohort study, 30 patients referring to the Orthopedic Clinic of Shohada Ashayer Hospital of Khorramabad, Iran, with a complaint of hallux valgus were randomly divided into two groups. The splints designed by the researches (slippers splints) were given to the case group, and the splints on the market including night splints and interdigital pads were given to the control group. The patients were followed every three months for a year and every time the weight bearing anteroposterior radiography of both feet were taken and hallux valgus and inter-metatarsal angles were measured. The data was analyzed by the SPSS software using repeated measure tests. In the case group that used the designed splints regularly, hallux valgus angles decreased more dramatically than in the control group (P<0.001). This study showed that, despite controversies over the nonoperative treatment of hallux valgus, if hallux valgus angle in patient is mild to moderate, the splint can be used as a nonoperative treatment. 相似文献
85.
Niyyati M Lasjerdi Z Nazar M Haghighi A Nazemalhosseini Mojarad E 《Journal of water and health》2012,10(1):140-146
A survey was conducted to determine the presence of free-living amoebae (FLA), especially Acanthamoeba and Naegleria, in river recreation areas in Tehran Province, Iran. All rivers surveyed were associated with human activity, and two were also a source of municipal tap water. Fifty-five water samples from 10 major rivers were screened for FLA and identified by morphological characters, PCR amplification targeting specific genes for Acanthamoeba (DF3 region of Rns gene) and other FLA (ITS PCR), and homology analysis. The percentage of positive FLA isolates was 27.3%, of which 80% were Acanthamoeba, assigned to the T4 and T15 genotype, and 20% were Naegleria. Isolation of Acanthamoeba T4 genotype (91.7%) from recreation areas could be a health threat and a sanitary risk associated with human activity where young people and tourists congregate in summer. Posting of warning signs and education of high-risk individuals are important for disease prevention. To the best of our knowledge this is the first report of genotype T15 (clustered with A. jacobsi) identified in Iran and the first report of the distribution of FLA such as Naegleria (N. pagei, N. clarki and N. fultoni) in recreation areas in rivers of Tehran Province using molecular methods. 相似文献
86.
Mahdieh Abbasalizad Farhangi 《Ecology of food and nutrition》2016,55(3):258-265
The current study was aimed to evaluate gestational weight gain and its socio-demographic determinants among pregnant women in north-west of Iran. In the current cross-sectional study, four hundred eighty one pregnant women aged 26.12 ± 7.45 years were enrolled. Data on pre-pregnancy weight, height, age, educational attainment, parity, household size, hemoglobin status and total pregnancy weight gain were extracted from routine health center records. The pregnant women were categorized based on their pre-pregnancy body mass index (BMI) as underweight, normal weight and overweight or obese according to the 2009 Institute of Medicine (IOM) recommendations. Participants were also classified according to their educational level into three ‘some school’, ‘high school’ and ‘college’ groups. Gestational weight gain in 27.6% of pregnant women was in normal IOM recommended range; while, weight gain in 49% and 23.2% of pregnant women was below and above recommended range respectively. Women with high educational attainment (≥12 years) have significantly higher weight gain compared with low-educated women (<12 years) (P < 0.001). Age was in negative relationship with gestational weigh gain even after adjusting for confounder effects of residency, educational attainment and household size (r = 0.2, P < 0.001). Our data showed a high prevalence of abnormal gestational weight gain in pregnant women attending to public health centers in northwest of Iran. Moreover educational level, parity and age were significant determinants of gestational weight gain in pregnancy. Special attention should be focused on prenatal nutritional status and health care programs in current health care services in Iran. 相似文献
87.
88.
Considerable numbers of congenital cardiac anomalies are missed at the time of delivery. Study reports show that congenital cardiac anomalies are the second most common birth defect in many countries. Despite this fact, our previous study showed that the prevalence of congenital cardiac anomalies is the fifth most common one, indicating that many of these defects might not be properly diagnosed at the time of delivery and birth. The aim of this study was to estimate the missing frequency of congenital cardiac anomalies at the time of delivery and birth. The population of the study was 185,650 births in the Northwest region of Iran covered by the Tabriz Registry of Congenital Anomalies. A total of 451 children with congenital cardiac anomalies were studied in the region from 2000 to 2009. The expected prevalence of congenital cardiac anomalies at birth was estimated to be 24.2 per 10,000 births while a prevalence of 9.2 per 10,000 births was observed at the same time and place. This indicated that 59.1% of children with congenital cardiac anomalies were not identified at birth (p-value less than 0.05). This proportion increased by 13% over the study period from 2000 to 2009 (p-value greater than 0.1). Our findings indicated that a remarkable frequency of congenital cardiac anomalies was not diagnosed at birth because there was no paediatric cardiologist available at the time of birth in the gynaecology and obstetrics wards. 相似文献
89.
90.
Nazar M Haghighi A Taghipour N Ortega-Rivas A Tahvildar-Biderouni F Nazemalhosseini Mojarad E Eftekhar M 《Parasitology research》2012,111(2):835-839
A survey was conducted on man-made recreational water located in different regions of Tehran, Iran to detect the free-living amoebae present in ponds and fountains of parks and squares. Fifty water samples from 22 municipal districts of Tehran were screened for free-living amoebae and identified by morphological characters and polymerase chain reaction amplification. Amoebae detected were identified as Hartmannella vermiformis (12 %) and Vannella persistens (4 %), which are the first reports of these two amoebas in recreational water environments of Iran. Since, H. vermiformis, which is highly similar to strains serving as hosts for Legionella pneumophila, is a common component of the microbial community in fresh surface water. Although Vannella spp. is not proved to be pathogenic itself, they are capable of harboring pathogenic intracellular organisms. Due to some reports related to pathogenicity of these amoebas, the particular hazard related to these microorganisms should be taken into account in the encounter with drinking and washing in these waters. We recommend control strategies based on physical removal rather than on disinfection to be adopted where necessary. 相似文献