جستجوی مقالات مرتبط با کلیدواژه « سمیت روی » در نشریات گروه « زیست شناسی »

The present experiment was aimed to investigate the improvement of salt tolerance in narcissus by exogenous application of sodium nitroprusside (SNP) in a factorial complete randomized block design with three replications at the Research Greenhouse, Islamic Azad University, Isfahan (Khorasgan) Branch during 2019-2020. Experimental treatments included irrigation by saline water at two levels 4 and 8 dS m-1 and control (without saline), as well as SNP (0, 100, 200, and 400 µM). The results indicated that elevated salt stress levels induce oxidative stress, including an increase in the hydrogen peroxide by 82% and malondialdehyde by 118% in plants. Severe salt stress reduced morphological traits, including a 40% decrease in flower longevity on the plant and a 49% decrease in the flowering duration of narcissus compared to non-stress conditions. The salt stress led to the change of antioxidant enzymes activities at different concentrations. The activity of superoxide dismutase enzyme positively correlated with salt treatment and increased up to 23%. While catalase enzyme increased up to 4 dS m-1 treatment by 87% and then decreased at a higher concentration in the leaves. However, SNP reduced oxidative damage in plants by improving antioxidant enzymes, proline and flavonoid content, ultimately, preventing the reduction of plant biomass. Finally, the present study showed that the exogenous application of SNP, especially at a concentration of 200 µM, improved narcissus tolerance to salinity stress by reducing the uptake of Na by 16%, as well as decreasing membrane lipid peroxides by 17%.

In dentistry, antimicrobial materials are selected due to their antimicrobial effects and tissue-compatibility. In the present study, cell-toxicity of calcium hydroxide and sodium fluoride powders were evaluated in L929 fibroblast cell line. Also in this study, possible effect of calcium hydroxide was evaluated in decreasing cell-toxicity effect of sodium fluoride.

Experimental materials were evaluated in time points of 6, 12, 24, 48 and 72 hrs with concentrations of 0.05, 0.1, 0.25, 0.5, 0.75, 1, 5, 25, 100, 500 and 1000 ppm by MTT test on L929 fibroblast cells and as negative control untreated cells were evaluated.  

Calcium hydroxide alone, showed low cell-toxicity (p<0.05). Sodium fluoride in concentrations of 500 and 1000 ppm showed a meaningful difference versus negative control sample (p<0.05). Combination of calcium hydroxide and sodium fluoride reduced sodium fluoride cell-toxicity meaningfully in concentration of 500 ppm (p<0.05).

Using of new compounds is so useful in dentistry for disinfection. One solution is reducing current compounds cell-toxicity. In the other hand, calcium hydroxide did not show noticeable cell-toxicity but it reduced sodium fluoride cell-toxicity in a combination form.

Actinobacteria are very important in the world in terms of the production of metabolites with various biological effects. This study was conducted with the aim of investigating the toxicity of the fermented extract obtained from Actinobacteria isolated from some biological resources of Iran on Artemia urmiana. These isolates were deposited in University of Tehran Microorganisms Collection (UTMC).

Forty-eight -76°C actinobacterial isolates were revived using ISP2 agar culture medium. Two bacterial discs were inoculated in ISP2 broth medium as a pre-cultivation medium. After 48 hours, 10 ml of the liquid was inoculated into the fermentation culture medium and heated for 7 days in a shaker incubator with 180 rpm, temperature of 28°C and pH of 7.2 ± 0.2. The fermentation broth was extracted using ethyl acetate, the solvent was evaporated using a low-pressure rotary evaporator. The toxicity of fermentation broth extracts was assayed against    40-hour Artemia urmiana nauplii.

According to the toxicity classification, among the all 48 isolates, 64.58% were highly toxic, 22.91% were moderate toxic, and 12.5% were in the low toxicity compounds group.

The results showed that more than half of the tested extracts had very high lethality on Artemia urmiana in a short time. Comparing the LC50 and LT50 values of the extracts with  similar studies, it was found that these extracts have a significant biological activity and can be used as a rich source in the production of metabolites with proper biological effects.

This study was performed to determine antibacterial and cytotoxic effects of fractionated venom of Vipera albicornuta snake under in-vitro condition.

Different fractions of Vipera Albicornuta venom were isolated using RP-HPLC and C18 column, followed by lyophilizing operation. Protein content of each fraction was estimated by Bradford method.Bactericidal-activity of each fractions in 20 μg/mL concentration toward Bacillus subtilis,Staphylococcus aureus and Escherichia coli strains was performed using MTT reduction and MIC and tetracycline (50 μg/ml) was used as standard antibiotic.Moreover,The cytotoxicity effect of fractions with most antibacterial effects on HepG2 cells was investigated using MTT reduction test and confirmed with neutral red uptake assay following exposure of cells with different protein concentrations of each fractions (10-20 μg/mL) and apoptosis effect was evaluated by Comet assay.

Our findings demonstrated that venom fractions of snake display different antibacterial effects against various tested bacteria. Based on the results, fractions No. 2 on B.subtilis, fractions 2 and 9 on E.coli and fractions 5, 7 and 9 on S.aureus shown the most effects. In addition, the results of this study confirmed that fractions Nos. 2 and 5 of venom produced the highest cytotoxicity on HepG2 cell line after 24 h treatment through induction of apoptosis and necrosis.In addition, this study confirmed that fractions No.2 and 5 produced the highest cytotoxicity on HepG2 cell line after 24 h of apoptosis and necrosis.

The results of study showed that isolated fractions of V.albicornuta venom have antibacterial and anti-cancer effects.

Leukemia is one of the most important diseases that affected human lives. Therefore, study of effective factors in order to control of this disease is very essential. This study was investigated the effect of cytotoxicity of extracts (n- Hexane, Diethyl ether, Methanol) from the algae Padina tenuis  Bory de Saint-Vincent on leukemia cell line. For this purpose, the required extracts of Padina tenuis  Bory de Saint-Vincent were prepared by rotary which was collected from the Namakdan rocky shores, Qeshm Island. Subsequently, human leukemia cell line was cultured in RPMI culture medium with 10% fetal bovine serum. The cytotoxic effect of different concentrations (10, 30, 75, 150, 300, 500 µg / ml) was measured by MTT method. Hexane, diethyl ether and methanol extracts were able to inhibit the proliferation of human leukemia cells at 258 µg / ml, 90 µg / ml and of 122 µg /ml concentrations, respectively, in vitro. Also, with increasing the concentration of extracts, the percentage of metabolic activity of cancer cells decreased. The results showed a significant difference in the effect of different solvents against blood cancer cells at a significance level of 95%

Fish mucus layers are the main surface of exchange between fish and the environment, and they possess important biological and ecological functions. In the present study, the antioxidant activity (reducing power, total antioxidant capacity, and free radical scavenging of DPPH) and cytotoxicity (test of saltwater shrimp larvae) of four species of Solea elongate, Euryglossa orientalis, Netuma bilineata, Muraenesox cinereus were investigated. The results showed that E. orientalis fish mucus had the highest reducing power (1.6 ± 0.2), N. bilineata fish mucus had the highest total antioxidant capacity (0.93 ± 0.3) and the highest percentage of free radical scavenging DPPH (89 ± 0.2). In the cytotoxicity test, the highest mortality rate under the influence of S. elongate mucus was about 97.5 ± 2.5. The results of the present study showed that fish mucus can be introduced as a potential source of natural biological compounds with high antioxidant activity and cytotoxicity.

Nowadays, probiotic bacteria such as Lactobacilli have been recognized as promising agents to prevent a large number of diseases, including cancer. This study aimed to evaluate the cytotoxic effects of Lactobacillus paracasei (IBRC_10784) extract on pancreatic cancer cell line ASPc-1 and to analyze the expression of bax, Bcl2, and DPC4 apoptotic genes.

This study was conducted on ASPC-1 pancreatic adenocarcinoma cell line to assess the effects of culture medium and Lactobacillus paracasei products on the expression of genes involved in apoptosis as well as DPC4 gene expression. Lactobacillus paracasei was cultured on specialized MSR broth medium and incubated for 48 hours in a CO2 incubator. After observing the growth of bacteria, the culture medium was centrifuged for 5 minutes at 9000 rpm and the supernatant was removed. Then, the supernatant was sterilized by a 0.22-micron syringe filter and was used in the subsequent steps. In the next step, AsPC-1 cells were treated with supernatant solution for 24 hours, followed by RNA extraction and cDNA synthesis. The Q-PCR reaction was performed using specific primers.

The findings of this research showed that the supernatant solution of Lactobacillus paracasei culture was able to change the expression of the studied genes, so that the expression of bax gene increased 1.86 times relative to the reference gene. Moreover, the expression of bcl-2 gene decreased by 4.56 folds compared to the reference gene. A notable point was the changing expression of DPC4 gene, which significantly increased to 2.67 folds in comparison to the reference gene (P<0.005).

According to the results of the present study, it seems that the increased expression of DPC4 tumor suppressor gene, which is one of the essential factors in TGF-β pathway, may be important in suppressing pancreatic cancer.

The radiation-resistant extremophile microorganisms can produce high amounts of carotenoids. However, the optimization of their metabolite production is critical for large-scale commercial purpose. This study aimed to investigate the production of carotenoid pigments by an extremophile strain phylogenetically close to the genus Cellulosimicrobium that has not been reported so far.

The influence of various carbon and nitrogen sources on the microbial biomass and pigment production of the studied strain were investigated using one-factor-at-a-time-approach. Antioxidant activity of the pigment was evaluated using free radical scavenging and ferric reducing antioxidant power. Besides, the antibacterial and cytotoxicity activity of the pigment extract were investigated using the agar well-diffusion method and cell metabolic activity assay, respectively.

The maximum amount of carotenoid pigment produced by the studied strain was achieved in the fermentation medium containing 1g/L yeast extract and 1g/L glucose (22.5 mg /L) that was 10.7 fold more than the unoptimized conditions (2.1 mg/L). The half-maximal effective concentration (EC50) values of the pigment were evaluated as much as 10.97 mg/mL and 6.02 μg/mL in the free radical scavenging and ferric reducing antioxidant power assay, respectively. Also, the pigments of this strain showed no toxic and inhibitory effect on the human fibroblast cell line.

As compared to previous studies, the carotenoid pigment extract of strain AZ displayed strong antioxidant activity. Therefore, the present study lays a foundation for future utilizations of Cellulosimicrobium strain AZ as a promising microorganism for commercial production of carotenoids in the food industry or sunscreens due to the antioxidant and non-cytotoxic activity of its carotenoid pigment.

The aim of the present study was to investigate the synergistic cytotoxicity effects of silver nanoparticles and bevacizumab against ovarian cancer cell line (A2780) and to analyze the expression of caspase 3 and Bcl-2 apoptotic genes.

The cytotoxicity of silver nanoparticles and bevacizumab at different concentrations including 62.5 to 1000 μg/ml and 1000 to 3000 μg/ml, respectively was investigated against A2780 cell line by MTT colorimetric method. Moreover, the expression of caspase 3 and Bcl2 apoptotic genes were studied using Real-Time PCR.

The results of this study showed that the silver nanoparticles and bevacizumab had dose-dependent toxicity and there were more significant cytotoxic effects than the single drug (p <0.05). Also, the IC50 values of silver nanoparticles and bevacizumab were 12.72±0.56 and 22.72±1.21 μg/ml, respectively. Also, the silver nanoparticles and bevacizumab changed the expression of caspase 3 and Bcl2 genes, respectively, which was significant compared to the housekeeping gene (p <0.05).

The results of this study showed that the silver nanoparticles-bevacizumab has a synergistic effect. However, more studies are needed to use this compound as a drug candidate.

In the present study, the effect of different structural forms of plasmids on the efficiency of their transfer into the host was investigated. The toxicity effects of various forms of plasmids on host cells were also investigated.

Supercoiled, circular, nicked, and linear plasmid forms were separated from agarose gel. These structural forms were transfected to HEK293 cells and the transfection efficiency and toxicity of each of these forms was evaluated using the MTT technique.

The results showed that transferring the supercoiled form of pcDNA3.1+ plasmid into the host is much higher than other forms. Moreover, the toxicity effects of the linear form on the host are much higher than in other forms. Therefore, the results indicate that the supercoiled form of the plasmid is suitable for increasing the transfect efficiency and reducing cell death.

Researchers can use the supercoiled plasmid form in gene transfer processes to dramatically increase the efficiency of this process.