Seasonal Changes of Fatty Acid Compositions in Overwintering Larvae of Rice Stem Borer, Chilo suppressalis (Lepidoptera: Pyralidae)

Atapour, Maryam,Moharramipour, Saeid,Barzegar, Mohsen Korean Society of Applied Entomology 2007 Journal of Asia-Pacific Entomology Vol.10 No.1

Cold acclimation and overwintering state can affect fatty acid compositions of insects. To determine compositional change of fatty acids during nondiapause and diapause stages, an experiment was conducted to investigate fatty acid constituents from whole body of C. suppressalis larvae. Five most abundant fatty acids were found to be palmitoleic (35-58%), palmitic (18-44%), oleic (14-23%), stearic (0.5-2.5%) and linoleic acid (0.4-2%). However, linolenic, erucic, lauric and myristic acid were found at lower level. Saturated fatty acids significantly decreased and conversely unsaturated fatty acids increased from August (pre-diapause) to October (initiation of diapause). The increase in seasonal cold hardiness during cold acclimation, exposed at $-15^{\circ}C$ for 24 h, was related to degree of fatty acid un-saturation. The elevation of palmitoleic acid content at low temperature resulted in an increase in the overall degree of unsaturation in the whole body. These results indicated the importance of unsaturated fatty acids composition to prepare larvae entering diapause phase.

Seasonal Changes of Fatty Acid Compositions in Overwintering Larvae of Rice Stem Borer, Chilo suppressalis (Lepidoptera: Pyralidae)

Maryam Atapour,Saeid Moharramipour,Mohsen Barzegar 한국응용곤충학회 2007 Journal of Asia-Pacific Entomology Vol.10 No.1

Cold acclimation and overwintering state can affect fatty acid compositions of insects. To determine compositional change of fatty acids during non- diapause and diapause stages, an experiment was conducted to investigate fatty acid constituents from whole body of C. suppressalis larvae. Five most abundant fatty acids were found to be palmitoleic (35-58%), palmitic (18-44%), oleic (14-23%), stearic (0.5-2.5%) and linoleic acid (0.4-2%). However, linolenic, erucic, lauric and myristic acid were found at lower level. Saturated fatty acids significantly decreased and conversely unsaturated fatty acids increased from August (pre-diapause) to October (initiation of diapause). The increase in seasonal cold hardiness during cold acclimation, exposed at -15℃ for 24 h, was related to degree of fatty acid unsaturation. The elevation of palmitoleic acid content at low temperature resulted in an increase in the overall degree of unsaturation in the whole body. These results indicated the importance of unsaturated fatty acids composition to prepare larvae entering diapause phase.

Corrosion Characteristics of TiNbMoMnFe High Entropy Thin Film Deposited on AISI316L for Biomedical Applications

Alireza Razazzadeh,Masoud Atapour,Mohammad Hossein Enayati 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.7

High entropy alloys (HEAs) have received tremendous attention in diferent applications because of their excellent corrosion resistance and superior mechanical properties. In the present work, a novel TiNbMoMnFe high entropy alloy systemwas synthesized and deposited on AISI 316L by DC magnetron sputtering system. The microstructure of the resulting thinflm was evaluated by grazing incidence X-ray difraction and feld emission electron microscope. It was found that the thinflm microstructure is composed of a crystalline solid solution (grain size of 76 nm) and an amorphous phase. The electrochemical investigations in Ringer’s solution revealed that a thin flm of 670 nm thick high entropy alloy has a low corrosioncurrent density of 0.024 μA cm−2, approximately 30% lower than that of the uncoated 316L. Meanwhile, the HEA thin flmshowed the highest pitting corrosion resistance and stability of the passive flm. The wettability examinations exhibited thatthe coated sample has a high contact angle of 90° in contrast to 60° for the uncoated ones. In summary, the TiNbMoMnFehigh entropy alloy thin flm shows great potential for use in biomaterial applications.

Effects of gamma radiation on the reproduction biology and mating competitiveness of citrus leafminer Phyllocnistis citrella Stainton

Shiva Osouli,Maryam Atapour 한국응용곤충학회 2018 Journal of Asia-Pacific Entomology Vol.21 No.1

The citrus leafminer (CLM), Phyllocnistis citrella Stainton, is one of the most serious pests of Iran's citrus nurserystocks. In this study, the effects of gamma radiation at doses of 100–450 Gy on the biological and reproductiveparameters of P. citrella were determined. The results showed that the mean percentage of pupal mortalityincreases with a rise in the dose. Also, the mean values of this parameter were higher for irradiated females,indicating higher sensitivity. The mean fertility of the irradiated females mated with normal males was affecteddrastically and reached zero at 300 Gy. The hatchability of the eggs laid by normal females mated with irradiatedmales dropped to 2% at the highest irradiation dose of 450 Gy. The results of this test showed that females have ahigher radio-sensitivity than males. The competitiveness values fluctuated from 0.2 to 0.6 at doses higher than200 Gy. The results showed that the male CLMs irradiated with sterilizing doses could compete suitably with theuntreated males in laboratory conditions.

Micromeritics and Release Behaviours of Cellulose Acetate Butyrate Microspheres Containing Theophylline Prepared by Emulsion Solvent Evaporation and Emulsion Non-solvent Addition Method

Mitra Jelvehgari,Fatemeh Atapour,Ali Nokhodchi 대한약학회 2009 Archives of Pharmacal Research Vol.32 No.7

The present research work compares the effect of microsphere preparation technique on micromeritics and release behaviors of theophylline microspheres. Microspheres were prepared by oil-in oil (O1/O2) emulsion solvent evaporation method (ESE) using different ratios of anhydrous theophylline to cellulose acetate butyrate (CAB). Cyclohexane was used as non-solvent to modify the ESE technique (MESE method) and the effect of non-solvent volume on properties of microspheres was investigated. The obtained microspheres were analyzed in terms of drug content, particle size and encapsulation efficiency. The morphology of microsphere was studied using scanning electron microscope. The solid state of microspheres, heophylline and CAB were investigated using X-ray, FT-IR and DSC. The drug content of microspheres prepared by MESE method was significantly lower (15.54% ± 0.46) than microspheres prepared by ESE method (41.08 ± 0.40%). The results showed that as the amount of cyclohexane was increased from 2 mL to 6 mL the drug content of microspheres was increased from 15.54% to 28.71%. Higher encapsulation efficiencies were obtained for microspheres prepared by ESE method (95.87%) in comparison with MESE method (64.71%). Mean particle size of microsphere prepared by ESE method was not remarkably affected by drug to polymer ratio, whereas in MSES method when the volume of cyclohexane was increased the mean particle size of microsphere was significantly decreased. The ratio of drug to polymer significantly changed the rate of drug release from microspheres and the highest drug release was obtained for the microsphere with high drug to polymer ratio. The amount of cyclohexane did not significantly change the drug release. Although, x-ray showed a small change in crystallinity of theophylline in microspheres, DSC results proved that theophylline in microspheres is in amorphous state. No major chemical interaction between the drug and polymer was reported during the encapsulation process.

Investigation on the Potential of Laser and Electron Beam Additively Manufactured Ti–6Al–4V Components for Orthopedic Applications

Mohamad Reza Bandekhoda,Mohammad Hossein Mosallanejad,Masoud Atapour,Politecnico di Torino,Abdollah Saboori 대한금속·재료학회 2024 METALS AND MATERIALS International Vol.30 No.1

In the present study, corrosion properties and biocompatibility of as-built and as-polished Ti–6Al–4V samples fabricatedby Electron Beam Melting (EBM) and Selective Laser Melting (SLM) were investigated and compared with a conventionalsample as a reference. Optical microscope, Scanning Electron Microscope equipped with Energy Dispersive Spectroscopy,and X-ray diffraction analysis were employed for studying the microstructure and composition of the samples. Polarization,electrochemical impedance, and immersion tests were carried out to investigate the corrosion behavior and bioactivity ofthe samples in the Simulated Body Fluid solution. The results revealed that the EBM samples exhibited a superior corrosionresistance compared to the SLM one, thanks to the absence of low corrosion resistant α′ martensitic phases and a higher fractionof β phase in the EBM samples. It was also observed that while the wrought Ti–6Al–4V samples had a higher corrosioncurrent density than the additively manufactured ones, both EBM and SLM processes had a lower corrosion resistance in theas-built state than in the as-polished. The immersion tests in the SBF solution revealed a more significant bioactivity for theEBM samples than the SLM samples. Higher levels of the β phase in the EBM microstructure stimulated the nucleation andgrowth of the apatite on the sample surface. Also, higher surface roughness in the as-built samples improved the bioactivityby increasing the metal/electrolyte interface and thus forming more OH−groups on the Ti alloy surface.

Sensitive and Noninvasive Detection of Aberrant SFRP2 and MGMT-B Methylation in Iranian Patients with Colon Polyps

Naini, M Alizade,Mokarram, P,Kavousipour, S,Zare, N,Atapour, A,Zarin, M Hassan,Mehrabani, G,Borji, M Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.4

Background: The pathogenesis of sporadic colorectal cancer (CRC) is influenced by the patient genetic background and environmental factors. Based on prior understanding, these are classified in two major pathways of genetic instability. Microsatellite instability (MSI) and CPG island methylator phenotype (CIMP) are categorized as features of the hypermethylated prototype, and chromosomal instability (CIN) is known to be indicative of the non-hypermethylated category. Secreted frizzled related protein 2 (SFRP2), APC1A in WNT signaling pathway and the DNA repair gene, O6-methylguanine-DNA methyltransferase (MGMT), are frequently hypermethylated in colorectal cancer. Detection of methylated DNA as a biomarker by easy and inexpensive methods might improve the quality of life of patients with CRC via early detection of cancer or a precancerous condition. Aim: To evaluate the rate of SFRP2 and MGMT hypermethylation in both polyp tissue and serum of patients in south Iran as compared with matched control normal population corresponding samples. Materials and Methods: Methylation-specific PCR was used to detect hypermethylation in DNA extracted from 48 polypoid tissue samples and 25 healthy individuals. Results: Of total polyp samples, 89.5% had at least one promoter gene hypermethylation. The most frequent methylated locus was SFRP2 followed by MGMT-B (81.2 and 66.6 percent respectively). Serologic detection of hypermethylation was 95% sensitive as compared with polyp tissue. No hypermethylation was detected in normal tissue and serum and its detection in patients with polyps, especially of serrated type, was specific. Conclusions: Serologic investigation for detection of MGMT-B, SFRP2 hypermethylation could facilitate prioritization of high risk patients for colonoscopic polyp detection and excision.