The effect of radiotherapy and chemotherapy on osmotic fragility of red blood cells and plasma levels of malondialdehyde in patients with breast cancer

BackgroundGamma radiation effects on the erythrocyte membrane from three different functional parts, lipid bilayer, cytoskeleton and protein components. When the red cell membrane is exposed to radiation, it loses its integrity and hemoglobin leaks out. In addition, irradiation leads to lipid peroxidation and the products of this process, leading to hemolysis. The aim of the present study was to measure osmotic fragility (OF) of red blood cells and malondialdehyde (MDA) levels as a marker of oxidative injury in breast cancer patients treated with radiation and chemotherapy.Materials and MethodsThe OF test was performed using different concentrations of a salt solution. The measurement of MDA was done with chemical methods.¹¹ The sampling was taken during three stages of treatment: first sample was taken before starting chemotherapy, the second sample was taken before radiation therapy and the third sample was taken after radiotherapy.ResultsNo statistically significant differences between levels of MDA in these three stages of treatment were observed. However, the comparison of mean levels of MDA showed an increase after radiotherapy. The OF rate did not show significant difference (P > 0.05) during the stages of treatment.ConclusionIn a standard treatment program of radiotherapy and chemotherapy lipid peroxidation level and OF do not significantly increase.     

PIA and rSesC Mixture Arisen Antibodies Could Inhibit the Biofilm-Formation in Staphylococcus aureus

Background:Staphylococcus aureus as a causative agent of hospital-acquired infections has been considered as the primary concern in biomaterial-related infections (BAIs).Methods:Following the purification of polysaccharide intercellular adhesion (PIA) as an efficient macromolecule in biofilm formation in the native condition, recombinant S. epidermidis surface-exposed rSesC protein, with the most homology to clumping factor A (ClfA) in S. aureus was cloned and expressed in a prokaryotic host as well. Fourier transform infrared spectrometry (FTIR) and Western blotting procedure analyzed purified PIA and protein, respectively. Then, the immune response was evaluated by measuring total IgG titers. Moreover, the capacity of Anti-biofilm forming activity of arisen antibodies to a biofilm-forming S. aureus strains was assessed by the semi-quantitative micro-plate procedure.Results:Data showed that the total IgGs were boosted in mice immunized sera. By performing an inhibition assay, the biofilm inhibitory effect of secreted antibodies to test strain was observed. Arisen antibodies against the mixture significantly were more potent than PIA and rSesC, when comparing individual antigens in a biofilm inhibition assay.Conclusion:immunization of mice with mentioned antigens especially a mixture of them, could eliminate the biofilm formation process in S. aureus. Hopefully, this study corresponds to the suggestion that the immunization of mice with PIA and rSesC candidate vaccines could protect against S. aureus infection.Key Words: PIA, Purification, Staphylococcus aureus, rSesC, Vaccine candidates     

Identification of Trichomonas Vaginalis Genotypes Using by Actin Gene and Molecular Based Methods in Southwest of Iran

Background:Trichomonas vaginalis (T. vaginalis) is a sexually transmitted protozoan parasite and the causative agent of trichomoniasis. The genetic characterization of T. vaginalis isolates shows notable genetic variation in this parasite. In the present study, we aimed to identify the T. vaginalis genotypes based on analyzing of actin gene in women specimens referred to health centers of Ilam city, southwest Iran.Methods:A total of 1765 female samples were collected from gynecology clinics in the city of Ilam. DNA was extracted from positive samples and nested polymerase chain reaction (Nested PCR) was used to amplify the actin gene. Then, partial sequencing and genotyping of the actin gene was performed. A phylogenetic tree was drawn using the detected genotypes of T. vaginalis and reference sequences.Results:Twenty-one of the 1765 urine and vaginal samples were positive for T. vaginalis. All infected individuals were married and their age in years was between 25 to 34. Further, the majority of infected women had cervical lesions, patchy erythema, and white color discharge. According to sequencing analysis, the isolates were identified as genotype G (n= 8) and genotype E (n= 2).Conclusion:From the collected samples, we were able to distinguish at least two genotypes (G and E) of T. vaginalis. However, lesser is known about these genotypes in the city of Ilam. Further studies with a higher number of isolates should be performed in order to understand the implications of these results in this region.Key Words: Actin gene, Genotypes, Ilam, Iran, Trichomonas vaginalis     

Purification and biochemical characterization of angiotensin I-converting enzyme (ACE) from ostrich lung: The effect of 2,2,2-trifluoroethanol on ACE conformation and activity

This work reports the purification and biochemical characterization of angiotensin I-converting enzyme (ACE) from ostrich (Struthio camelus) lung. The molecular weight of the purified enzyme was approximately evaluated to be 200 kDa and the maximum enzyme activity was observed at pH 7.5. The enzyme activity was increased by detergents of Triton X-100 (0.01%), cetyltrimethylammonium bromide (CTAB) (0.1 and 1 mM) and sodium dodecyl sulfate (SDS) (0.1 mM), while decreased by Triton X-100 (1% and 10%) and SDS (1 mM and 10 mM). The secondary and tertiary structure and activity of ACE in the absence and presence of trifluoroethanol (TFE) were investigated using circular dichroism, fluorescence quenching and UV–visible spectroscopy, respectively. Our results revealed that TFE stabilizes ACE at low concentrations, while acts as a denaturant at higher concentration (20%). The K_m, K_cat and K_cat/K_m values of ostrich ACE towards FAPGG were 0.8 × 10^?4 M, 59,240 min^?1 and 74 × 10⁷ min^?1 M^?1, respectively. The values of IC₅₀ and K_i for captopril were determined to be 36.5 nM and 16.6 nM, respectively. In conclusion, ostrich lung ACE is a new enzyme which could be employed as a candidate for studying ACE structure and its natural or synthetic inhibitors.     

Biochemical characterization of an extracellular polyextremophilic α-amylase from the halophilic archaeon Halorubrum xinjiangense

An extracellular haloalkaliphilic thermostable α-amylase producing archaeon was isolated from the saltwater Lake Urmia and identified as Halorubrum xinjiangense on the basis of morphological, biochemical, and molecular properties. The enzyme was purified to an electrophoretically homogenous state by 80 % cold ethanol precipitation, followed by affinity chromatography. The concentrated pure amylase was eluted as a single peak on fast protein liquid chromatography. The molecular mass of the purified enzyme was about 60 kDa, with a pI value of 4.5. Maximum amylase activity was at 4 M NaCl or 4.5 M KCl, 70 °C, and pH 8.5. The K _m and V _max of the enzyme were determined as 3.8 mg ml^?1 and 12.4 U mg^?1, respectively. The pure amylase was stable in the presence of SDS, detergents, and organic solvents. In addition, the enzyme (20 U) hydrolyzed 69 % of the wheat starch after a 2-h incubation at 70 °C in an aqueous/hexadecane two-phase system.     

Physiological responses of Yellowfin seabream (Acanthopagrus latus) to acute salinity challenge

ABSTRACT

One hundred and eight juvenile Acanthopagrus latus were transported from their natural habitat and kept in tanks (300 L) with 20 ppt salinity for 14 days. After 24h starvation, the fish were exposed to salinity of 34, 12, and 5 ppt; then, blood samples were taken after 0, 2, 24, and 48h after the exposure. Blood electrolytes did not show significant changes in response to variation in the environmental salinities. Cortisol and ALP increased (not significantly) in all groups after 2h (P<0.05) and returned to the basal value within 24 h. Glucose and lactate levels increased significantly in all experimental groups after 2h (P<0.05) and returned to the basal value within 48 and 24h, respectively. Triglyceride did not show any significant change during the trial. Our findings showed juvenile A. latus could acclimate to a range of salinities from 5% to 35% within 48h. Also, the metabolic changes were more related to the time of sampling than the salinity challenge, suggesting that adaption occurred during the time of the study.