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161.
Limonene, a major constituent of citrus essential oil isolated from abraded fresh peels of bitter orangeCitrus aurantium L., was tested for its toxicity against early 4th instar larvae ofCulex quinquefasciatus Say. The response of treated larvae was concentration-dependent and LC90s were 53.80 and 32.52 ppm after 24 and 48 h of treatment respectively. Limonene treated water was less favorable for oviposition by females ofCx. quinquefasciatus.  相似文献   
162.

Background:

Apolipoprotein A2 (APOA2) is the second major apolipoprotein of the high-density lipoprotein cholesterol (HDL-C). The study aim was to identify APOA2 gene variation in individuals within two extreme tails of HDL-C levels and its relationship with HDL-C level.

Methods:

This cross-sectional survey was conducted on participants from Tehran Glucose and Lipid Study (TLGS) at Research Institute for Endocrine Sciences, Tehran, Iran from April 2012 to February 2013. In total, 79 individuals with extreme low HDL-C levels (≤5th percentile for age and gender) and 63 individuals with extreme high HDL-C levels (≥95th percentile for age and gender) were selected. Variants were identified using DNA amplification and direct sequencing.

Results:

Screen of all exons and the core promoter region of APOA2 gene identified nine single nucleotide substitutions and one microsatellite; five of which were known and four were new variants. Of these nine variants, two were common tag single nucleotide polymorphisms (SNPs) and seven were rare SNPs. Both exonic substitutions were missense mutations and caused an amino acid change. There was a significant association between the new missense mutation (variant Chr.1:16119226, Ala98Pro) and HDL-C level.

Conclusion:

None of two common tag SNPs of rs6413453 and rs5082 contributes to the HDL-C trait in Iranian population, but a new missense mutation in APOA2 in our population has a significant association with HDL-C.  相似文献   
163.
The Persian squirrel (Sciurus anomalus) is habitat in the Middle East countries and feed on pine acorns and other seeds. The present study was carried out to investigate the histological and volumetric features of the oesophagus in Persian squirrels. Five adult male Persian squirrels were included in the study. The cervical, thoracic and abdominal oesophagus of all subjects were processed routinely and sectioned in a serial manner. Then, the total volume of the oesophagus and its different layers were estimated using Cavalieri's principle. Histological assessment revealed a non‐keratinized stratified squamous epithelium lining the mucosa. No glands were seen in the lamina propria and submucosa. Lamina muscularis was present as a distinct layer of smooth muscle cells separating the lamina propria from the tunica submucosa. The tunica muscularis consisted of two distinct layers of striated muscle fibres: inner circular and outer longitudinal that was intermingled with few scattered smooth muscle fibres especially in the abdominal region. The thoracic region contained more amount of the lamina muscularis and tunica muscularis in comparison to the cervical or abdominal regions. The obtained results revealed that the histological structure of the Persian squirrel oesophagus has differences and similarities with other rodents and even with other species of squirrel. These findings would be useful to improve the knowledge in the areas of histological structure of the rodent digestive system.  相似文献   
164.

Background:

The serum concentration of high-density lipoprotein cholesterol (HDL-C) is one of the important heritable risk factors for cardiovascular disease and is a target for therapeutic intervention. In this study, we aimed to evaluate the effects of lecithin cholesterol acyltransferase (LCAT) gene polymorphism rs5923 on LCAT enzyme activity and serum HDL-C concentration.

Methods:

The study population was selected from consecutive individuals with HDL-C ≤ 5th percentile (n = 73) and extremely high HDL-C ≥ 95th percentile (n = 57) who had participated in the Tehran Lipid and Glucose Study. The rs5923 polymorphism was genotyped using direct sequencing. LCAT activity was measured by fluorometric assay kit, and lipid concentrations were measured using the enzymatic colorimetric method.

Results:

The genotype frequencies were significantly different between the high HDL-C group (CC 94.7%, CT 5.3%) and the low HDL-C group (CC 83.6%, CT 16.4%) (P = 0.048). The T-allele frequencies in subjects with low and high HDL-C were 0.082 and 0.026, respectively (P = 0.16). The association of the single-nucleotide polymorphism rs5923 with low HDL-C was not statistically significant after adjustment for age, sex, and BMI (odd ratio = 2.65, 95% confidence interval = 0.32-21.5, P = 0.36, regression logistic analysis). Also, the effects of LCAT enzyme activity did not depend on the HDL-C level (P = 0.24).

Conclusion:

rs5923 polymorphism is not associated with low HDL-C levels in Iranian population. Key Words: Polymorphism, Single nucleotide, Lipoproteins  相似文献   
165.

Background:

Existence of bacterial host-cell DNA contamination in biopharmaceutical products is a potential risk factor for patients receiving these drugs. Hence, the quantity of contamination must be controlled under the regulatory standards. Although different methods such as hybridization assays have been employed to determine DNA impurities, these methods are labor intensive and rather expensive. In this study, a rapid real-time PCR test was served as a method of choice to quantify the E. coli host- cell DNA contamination in widely used recombinant streptokinase (rSK), and alpha interferon (IFN-α) preparations.

Methods:

A specific primer pair was designed to amplify a sequence inside the E. coli 16S rRNA gene. Serial dilutions of DNA extracted from E. coli host cells, along with DNA extracted from Active Pharmaceutical Ingredients of rSK, and IFN-α samples were subjected to an optimized real-time PCR assay based on SYBR Green chemistry.

Results:

The test enabled us to detect a small quantity of genomic DNA contamination as low as 0.0002 pg in recombinant protein-based drugs. For the first time, this study showed that DNA contamination in rSK and IFN-α preparation manufactured in Pasteur Institute of Iran is much lower than the safety limit suggested by the US FDA.

Conclusion:

Real-time PCR is a reliable test for rapid detection of host-cell DNA contamination, which is a major impurity of therapeutic recombinant proteins to keep manufacturers’ minds on refining drugs, and provides consumers with safer biopharmaceuticals. Key Words: DNA contamination, Real-time PCR, Streptokinase, Interferon-alpha (IFN-α)  相似文献   
166.
Toxoplasmosis is a widespread zoonotic disease that causes significant morbidity and mortality in human fetus and in immunocompromised patients. Moreover, it becomes a major cause of abortion in sheep and goats. Since consumption of meat of infected lamb and goat is considered as the main sources of human infection in Iran, this study was undertaken to determine the prevalence of Toxoplasma infection in edible tissues of sheep and goats in Shiraz in 2008. Samples of brain, tongue, liver, and muscles of neck, intercostals, and femoral were taken from 56 sheep and 22 goats and tested by PCR. The total prevalence of Toxoplasma infection among animals was found to be 33.3%. Five out of 22 goats (22.7%) and 21 out of 56 sheep (37.5%) were infected by Toxoplasma. Differences between the prevalence rate of infection among females (nine out of 14 = 46%) and males animals (12 out of 45 = 29.5%) was significant (P = 0.013). Furthermore, a positive correlation was found between the age of animals and the rate of infection; animals greater than 2 years old showed a higher rate of infection (47%) in comparison with those less than 2 years old (25%, P = 0.04). The highest infected tissue was tongue (21.8%) followed by brain (19.2%) and femoral and intercostal muscles (17.9%). This study demonstrated a high level of Toxoplasma infection in slaughtered animals in Shiraz and these should be considered as the main sources of infection for human population in the region.  相似文献   
167.
Respiratory diseases in calves are responsible for major economic losses in both beef and dairy production. Several viruses, such as bovine respiratory syncytial virus (BRSV), bovine herpes virus-1 (BoHV-1), bovine parainfluenza virus-3 (BPI-3V), bovine viral diarrhea virus (BVDV), and bovine adenoviruses (BAV), are detected in most clinical cases with respiratory signs. The aim of this study is to define seroprevalences of five major viral causes of bovine respiratory infections in cattle in central region of Iran (Esfahan province). The population targeted was 642 dairy cows (Holstein–Friesian) from 25 farms. Samples of blood serum from female cattle were examined. Sera were tested by commercial ELISA kits to detect antibody against BRSV, BoHV-1, BPI-3V, BVDV, and BAV-3. The results were analyzed by Chi-square test. In the present study, seroprevalences of BRSV, BoHV-1, PI3V, BVDV, and BAV-3 were 51.1%, 72%, 84.4%, 49.2%, and 55.6%, respectively. The present study shows that infections of bovine respiratory viruses are very common in cattle in Esfahan.  相似文献   
168.
Set marks are fabric defects in weft direction which are caused by an interruption of the weaving process. In this study, based on one-quarter fractional factorial design, among eight parameters of weaving machine, i.e. horizontal and vertical position of back rest roller, horizontal position of warp stop motion, shed crossing degree, shed crossing point position, warp tension, stoppage position of machine, and stoppage time, four most effective parameters was determined. These parameters were stoppage position of machine, vertical position of back rest roller, shed crossing point, and horizontal position of warp stop motion. Then using full factorial design effectiveness of these parameters was evaluated statistically at 99 % confidence level and effect of them on set mark studied in detail. Statistical evaluations showed that the stoppage position of machine was the most effective parameters on intensity of set mark of multifilament polyester fabric. A specific image capturing device for using on weaving machine based on CCD camera was designed. Image processing technique was used to measure the pickspacing in stop zone objectively. Five picks before and five picks after stoppage was considered as stop zone and the standard deviation of pickspacing was used as a criterion which interpret this defect. Dynamic loading of warp yarns were execute to evaluate the relaxation behavior of polyester multifilament warp yarns.  相似文献   
169.
170.
The content and fractionation of seven heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, and Zn) were determined in 28 surface soil samples (0–20 cm) of agricultural topsoil from Isfahan Province in central Iran. The order of abundance of metals in the soils was Fe (1240.4 mg kg?1) > Mn (95.7 mg kg?1) > Pb (51.6 mg kg?1) > Zn (23.8 mg kg?1) > Ni (13.4 mg kg?1) > Cu (7.0 mg kg?1) > Cd (2.8 mg kg?1). Iron, Mn, Ni, Pb, and Zn existed in paddy soils mainly in Fe-Mn oxides (53.6 %, 65.2 %, 40.4 %, 40.8 %, 53.3 %, respectively), whereas Cu and Cd occurred essentially as residual mineral phase (41.4 %) and carbonate (36.1 %), respectively. The mobile and bioavailable fractions of Cd, Cu, Fe, Mn, Ni, Pb, and Zn in paddy soils averaged 48.8, 20.8, 0.79, 29.2, 28.5, 41.1, and 24.8 %, respectively, which suggests that the mobility and bioavailability of the seven metals probably decline in the following order: Cd > Pb > Mn ≥ Ni > Zn > Cu ? Fe, suggesting greater contribution of anthropogenic Cd. As Cd in soil is easily accumulated by plants through the root system, the concentration of Cd in these paddy soils could be a concern to human health.  相似文献   
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