ABSTRACT
BACKGROUND: To explore practical applications of carbon nanotubes (CNTs) in biomedical fields the properties of their interaction with biomolecules must be revealed. Recent years, the interaction of CNTs with biomolecules is a subject of research interest for practical applications so that previous research explored that CNTs have complementary structure properties with single strand DNA (ssDNA). OBJECTIVES: Hence, the quantum mechanics (QM) method based on ab initio was used for this purpose. Therefore values of binding energy, charge distribution, electronic energy and other physical properties of interaction were studied for interaction of nucleic acid bases and SCNT. MATERIALS AND METHODS: In this study, the interaction between nucleic acid bases and a (4, 4) single-walled carbon nanotube (SCNT) were investigated through calculations within quantum mechanics (QM) method at theoretical level of Hartree-Fock (HF) method using 6-31G basis set. Hence, the physical properties such as electronic energy, total dipole moment, charge distributions and binding energy of nucleic acid bases interaction with SCNT were investigated based on HF method. RESULTS: It has been found that the guanine base adsorption is bound stronger to the outer surface of nanotube in comparison to the other bases, consistent with the recent theoretical studies. In the other words, the results explored that guanine interaction with SCNT has optimum level of electronic energy so that their interaction is stable. Also, the calculations illustrated that SCNT interact to nucleic acid bases by noncovalent interaction because of charge distribution an electrostatic area is created in place of interaction. CONCLUSIONS: Consequently, small diameter SCNT interaction with nucleic acid bases is noncovalent. Also, the results revealed that small diameter SCNT interaction especially SCNT (4, 4) with nucleic acid bases can be useful in practical application area of biomedical fields such detection and drug delivery.
ABSTRACT
BACKGROUND: Toxoplasmosis is the most common disease in humans and animals (zoonosis) caused by the protozoan parasite Toxoplasma gondii. The disease is usually appeared as asymptomatic in immunocompromised individuals but its most common symptom is lymphadenopathy. Shortly before or during the first trimester of pregnancy, this disease can be transferred to the fetus and cause serious infection in the fetus. In late pregnancy (third trimester), the complications of this infection is very low or unsigned. Due to the absence of non-specific clinical symptoms or slight infection in pregnant women, prenatal diagnosis is often impossible. OBJECTIVES: Since no research compared these two methods, we decided to compare these methods and determine which method works better for diagnosis of toxoplasmosis. PATIENTS AND METHODS: In this study, 50 pregnant women who referred to the Chalus Health Center laboratory were included and the blood samples were tested for presence of IgG and IgM antibodies of Toxoplasma gondii by both ELISA and Chemiluminescence methods. RESULTS: Of the 50 samples tested by the ELISA method, 26 samples (52%) were positive for IgG . No samples were positive for IgM. Of the 50 samples tested by the Chemiluminescence method, 28 samples (56%) were positive for IgG. No samples were positive for IgM. CONCLUSIONS: A significant relationship between the age of the youngest child and the infection rate was seen. No significant correlation between age, number of individuals in the household, number of children, location, type of construction, consumption of greens, the way of greens and meat consumption, drug use, history of stillbirth and infection levels was seen.
ABSTRACT
BACKGROUND: The exposure to noxious agwents such as lead my cause lung disorders. OBJECTIVES: In the present study, pulmonary function tests and self-reported respiratory symptoms in lead exposure workers were compared with matched control subjects. MATERIALS AND METHODS: The frequency of respiratory symptoms were evaluated in a sample of 108 lead exposure workers and 100 control subjects with similar age using a questionnaire including questions on respiratory symptoms in the past year. Pulmonary function tests (PFT) were also measured in lead exposure workers and in controls. RESULTS: Most lead exposure workers (63%) reported work-related respiratory symptoms. Chest tightness (26%), cough (17%) and sputum (16%) were the most common symptoms and only 6% of lead exposure workers reported wheezing (P < 0.001 for all case except wheezing). Most PFT values were also significantly reduced among lead exposure workers (P < 0.05 to P < 0.001 except MEF75, MEF50, MEF25, and MMEF. The lead concentration in urine and serum of lead exposure workers were significantly higher than control (P < 0.001 for both cases). CONCLUSIONS: These results showed that c lead exposure workers have higher frequencies of respiratory symptoms higher serum and urine lead concentration but lower PFT values.
