RESUMEN
BACKGROUND: Cytochrome P450-dependent monooxygenases are a very important metabolic system involve in insecticide resistance. This study was conducted to find the association between the expression level of cytochrome P450 (CYP450) and permethrin-resistance level among four strains of the German cockroach Blattella germanica (L) (Blattodea: Ectobiidae). METHODS: Three field strains of German cockroach with different frequency of exposure to pesticides, and a laboratory susceptible strain were used in the present study. Insecticide susceptibility bioassays were carried out to detect resistance to permethrin. The concentration of CYP450 in each strain was determined using ion-exchange HPLC chromatography. Biochemical assays was performed to analyse CYP450 activities. RESULTS: The resistance ratios (RR) to permethrin among three field strains were 3.29, 4.10 and 6.17-fold comping with the susceptible stain. The CYP450 activity of three field strains was 1.6, 2.4 and 2.7 times higher than in the susceptible stain. The amount of CYP450 per mg of protein was significantly different between the susceptible and the three resistant strains. The resistant cockroaches showed a relatively high expression of CYP450 enzymes. A strong correlation was found between permethrin resistance level and total concentration of CYP450 enzymes. CONCLUSION: The results of current study show that more frequent usage of a pyrethroid insecticide cause the metabolic insecticide resistance to rise in German cockroach. Therefore, there is a ratio correlation between resistance level and monooxygenases activities in insect. Thus, the control program must be managed according to history of pesticide usage.
RESUMEN
BACKGROUND: Congenital hypothyroidism is one of the most common endocrine disrupters and metabolism, and is one of the most important preventable causes of physical and mental disabilities. METHODS: This was a case-control study, in which 54468 infants were screened from 2006 to 2014 in Shahre-Kord, western Iran. To describe the data, central and dispersion indices such as mean and standard deviation was used. For modeling, logistic regression was used. All the tests were performed at the significant level of 5%. RESULTS: Overall, 111 cases were diagnosed with hypothyroidism, which made the prevalence value equal to 2 cases per 1000 births. The prevalence in females and males was 1.9 and 2.2 per 1,000 birth, respectively. The odds ratio for this disorder was 4.47(2.42-9.28) for the neonates with a family history of hypothyroidism and 1.72(1.05-2.82) for those born through cesarean. CONCLUSION: The incidence of this disorder is similar in males and females, and the incidence of this disease in people with a family history is far more than others.
RESUMEN
PURPOSE: The aim of this study was to estimate the incidence of colorectal cancers in Iran. The results of this study are based on a screening program that is being implemented in Isfahan province. MATERIAL AND METHODS: In this study, about 137,000 people were screened for colorectal cancer and adenomatous polyps in 2 steps during the year 2018. RESULTS: Based on the findings of this study, the incidence of adenomatous polyps was reported to be 389 (95% CI, 365-422) per 100,000 population. The incidence of adenomatous polyps was reported to be 483 (95% CI, 446-520) and 316 (95% CI, 286-346) in men and women, respectively (p < 0.001). Also, the incidence of colorectal cancer was reported to be 33 (95% CI, 23-42) per 100,000 population. The incidence of colorectal cancer in men and women was reported to be 41 (95% CI, 30-51) and 26 (95% CI, 17-34), respectively, indicating a statistically non-significant difference (p = 0.29). CONCLUSION: Based on the result of this study, despite a low participation rate of the target population in the screening program, the incidence of adenomatous polyps and colorectal cancer is relatively high in the average-risk population.