Rapid identification and authentication of closely related animal cell culture by polymerase chain reaction

Animal cell lines are important resources for research and diagnostic applications. Cross-contamination and misidentification of cell lines, however, can cause major problems for research (for example, false results that come from contamination cells may mislead the science). Hence, it is imperative to routinely monitor cell lines for identity and authenticity. Here, we extend our previous work on identification and authentication of animal cell culture by polymerase chain reaction (PCR) amplification and DNA sequencing. A PCR-based method for rapid identification and authentication of closely related cell lines was described. In this method, two new primers were designed based on high homology in the aldolase gene family. Used together with our previous primers, the combinations of primers were able to differentiate closely related species, including human from monkey and mouse from rat. This PCR assay provides a rapid, simple, sensitive, and cost-effective method for authentication of closely related cell lines. The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the funding agency.     

Identification and authentication of animal cell culture by polymerase chain reaction amplification and DNA sequencing

Polymerase chain reaction (PCR) amplification and deoxyribonucleic acid (DNA) sequence analysis were used to identify the species origin of cell lines used in a cell culture facility where various cell lines of different species are routinely propagated. The aldolase gene family was selected for PCR amplification because the DNA sequences of this gene are highly conserved over a wide range of animals and humans. A total of 36 cell lines representing 13 different species were selected for this study. The DNA from each cell line was amplified, and PCR products were analyzed by agarose gel electrophoresis. The results showed unique profiles of amplified bands on agarose gels that allowed differentiation among non-closely related species. However, DNA amplification of closely related species, including rat and mouse or human and primate, resulted in similar and indistinguishable banding patterns that could be further differentiated by DNA sequence analysis. These results suggested that aldolase gene amplification coupled with DNA sequence analysis is a useful tool for identification of cell lines and has potential application for use in identification of interspecies cross-contamination.     

Effects of PM2.5 and NO2 on the 8-isoprostane and lung function indices of FVC and FEV1 in students of Ahvaz city,Iran

The aim of this study was to determine the correlation between PM_2.5 and NO₂ pollutants and oxidative stress marker (8-isoprostane) and lung function tests (FVC and FEV₁) in healthy children who were living and studying in three different areas of Ahvaz city including A₁: Naderi site with high traffic, A₂: Alavi Alley site with average traffic, and A₃: Ein 2 site with low traffic (a rural area on the suburb of Ahvaz). 30 students in the 12–13 year-old range were selected from each studied zone (1, 2 and 3 sites) during three months of year. Of each student, one sample was taken every two weeks to measure 8-isoprostane of exhaled breath condensate (EBC). Air pollution data were collected from three air quality monitoring stations. Also, the relationship between air pollution and 8-isoprostane as well as lung function tests were determined using generalized estimating equations (GEE). The mean concentration of PM_2.5 and NO₂ in A₁, A₂ and A₃ areas were 116, 92 and 45 (μg/m³) also 77, 53 and 14 (ppb) respectively. Among all studied students, there was a significant correlation between the increase of mean concentration of PM_2.5 and NO₂ in 1–4 before sampling day, increased 8-isoprostane concentration and decreased FEV₁, while there was no significant correlation between them and decreased FVC. In A₁ site, an increase in IQR (13 μg/m³) PM_2.5 and IQR (6.5 ppb) NO₂ on 1–4 days before sampling was associated with 0.38 unit (95% CI: 0.11, 0.65) and 1.1 unit (95% CI: 0.85, 1.35) increase in 8-isoprostane concentration, also decreased 121 ml and 190 ml FEV₁, respectively. Results showed that the short-term exposure to traffic-related air pollution can decrease the values of lung function indices and increase the oxidative stress. It may adversely affect children’s lungs.     

Life-history parameters of the western flower thrips,Frankliniella occidentalis,are affected by host plant salinity stress

Salinization, as one of the foremost abiotic stresses, is an intensifying problem in many agroecosystems. Climatic changes, along with altering land use and also salinity of irrigation water all lead to enhanced soil salinity in agricultural lands. Changes in plant characteristics, as a result of raising soil salinity, may impose bottom-up impact on plant-feeding insects. We assessed the bottom-up impact of salinity stress on demographic traits of the western flower thrips (WFT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), on cherry tomato, Solanum lycopersicum L. var. cerasiforme (Solanaceae) plants under greenhouse conditions (27 ± 2 °C, 65 ± 5% r.h., and L16:D8 photoperiod). Our results indicated that salinity stress interfered with the immature development period, adult longevity, and sex ratio of WFT. Salinity stress biased the sex ratio in favor of males. Significant concentration-dependent differences were observed in the intrinsic (r) and finite (λ) increase rates and the net reproduction rate (R₀) of WFT at different salinity levels. Salinity adversely influenced WFT development; nonetheless, population projection forecasted an ascending WFT population growth under moderate salinity stress of 100 mM (2.8 dS m⁻¹ of NaCl), whereas severe salinity stress of 150 mM (4.7 dS m⁻¹ of NaCl) resulted in remarkable fitness costs in WFT. This study demonstrates that WFT has the potential to become problematic in regions with moderate salinity. Therefore, it might exacerbate the detrimental impact of salinity on tomato production. The current survey provides information on the abundance of WFT on saline-stressed tomato plants, thereby contributing to developing environmentally friendly measures to manage this notorious species in ecosystems under salinity stress.     

Preparation of Pickering Flaxseed Oil-in-Water Emulsion Stabilized by Chitosan-Myristic Acid Nanogels and Investigation of Its Oxidative Stability in Presence of Clove Essential Oil as Antioxidant

Food Biophysics - The aim of this study was to obtain a stable flaxseed oil (FSO)-in-water Pickering emulsion (PE) stabilized by chitosan (CS)-myristic acid (MA) nanogels and to investigate the...     

An Early Diagnostic Tool for Diabetic Peripheral Neuropathy in Rats

The skin’s rewarming rate of diabetic patients is used as a diagnostic tool for early diagnosis of diabetic neuropathy. At present, the relationship between microvascular changes in the skin and diabetic neuropathy is unclear in streptozotocin (STZ) diabetic rats. The aim of this study was to investigate whether the skin rewarming rate in diabetic rats is related to microvascular changes and whether this is accompanied by changes observed in classical diagnostic methods for diabetic peripheral neuropathy. Computer-assisted infrared thermography was used to assess the rewarming rate after cold exposure on the plantar skin of STZ diabetic rats’ hind paws. Peripheral neuropathy was determined by the density of intra-epidermal nerve fibers (IENFs), mechanical sensitivity, and electrophysiological recordings. Data were obtained in diabetic rats at four, six, and eight weeks after the induction of diabetes and in controls. Four weeks after the induction of diabetes, a delayed rewarming rate, decreased skin blood flow and decreased density of IENFs were observed. However, the mechanical hyposensitivity and decreased motor nerve conduction velocity (MNCV) developed 6 and 8 weeks after the induction of diabetes. Our study shows that the skin rewarming rate is related to microvascular changes in diabetic rats. Moreover, the skin rewarming rate is a non-invasive method that provides more information for an earlier diagnosis of peripheral neuropathy than the classical monofilament test and MNCV in STZ induced diabetic rats.