نشریه دانش زیستی ایران
سال پانزدهم شماره 3 (پاییز 1399)

Salinity is one of the most important abiotic stresses for plants and its adverse effects on different stages of plant growth and yield have been reported. Salinity can reduce seed germination as the most sensitive stage of plant growth. The use of silver nanoparticles has been suggested to improve the germination of some plants in salinity conditions. On the other hand, consuming spinach is highly recommended due to its high nutritional value. In this study, aloe vera extract was used for synthesis of silver nanoparticles. Then, the effects of salinity on seed germination of spinach and the role of silver nanoparticles on seed germination indices in this plant were investigated. The formation of silver nitrate nanoparticles was investigated using a spectrophotometer, XRD analysis, and electron microscopy. Spherical nanoparticles, with an average size of 11.97 nm to 29.46 nm were observed. Treatments in a completely randomized design with three replications of green silver nanoparticles at concentrations of 10, 20, 40, 80 and 100 ppm and salinity at four levels of 0, 50, 100 and 150 mM on spinach seed germination process were investigated . The results showed that the germination process under salinity conditions decreased significantly compared to the control group. Treatment of 40 ppm concentration of silver nanoparticles for different levels of salinity had a significantly increased effect on germination indices at 1% level .

During research in different seasons (winter and spring, summer and autumn), freshwater crabs in the eastern rivers of Tehran province (Jajroud, Hablehroud and Lar) in Fasham, Saeedabad, Khojir, Zarrin Dasht and Simindasht stations were carried out using hand net. They were evaluated in terms of carapace length and width, weight and body color. Finally, the results of this study showed that the species of crab found was Potamon persicum, which had a strong and positive correlation between carapace length, carapace width and also the weight of this crab in the samples found of Rivers (Jajrud and Hablehrood), stations (Fasham, Saeedabad, Khojir, Zarindasht and Simindasht) and gender did not affect the carapace length, carapace width and weight of this crab. In terms of average population distribution, P. persicum crabs were the same in Jajroud and Hableh Rud rivers as well as Fasham, Saeedabad, Khojir, Zarrin Dasht and Simin Dasht stations, but this average population distribution was significantly higher in summer and autumn than in winter and spring (p < 0.05). The population frequency of this crab was 70% in Jajroud river and 30% in Hablehrood; At Fasham, Saeedabad, Khojir, Zarrin Dasht and Simin Dasht stations, the frequencies were 32, 19, 18, 21 and 10% of the total samples, respectively. The results of body color also showed that the color of the carapace and legs were often dark brown and in some cases light brown.

The conversion of chemical energy to light by a living organism, bioluminescence, is an alluring process that catalyzes by enzymes generically called luciferases. This enzyme has wide applications as a reporter gene in in vivo imaging. In spite of wide range of luciferase applications, some inherent properties limit further application and development of this technology, including the low stability of the enzyme, a low turnover number, and a high Km for the substrate ATP.Due to the low stability of luciferase enzyme, the present study was performed to evaluate the effect of single amino acid mutations on the stability of luciferase enzyme of Iranian species Lamphyris Turkestanius using bioinformatics web servers and molecular dynamics simulation.For this purpose, to determine the stability, the mutations were tested using I-Mutant-2, Pop-music, Cupsat, istable, MUpro and Protparam and foldx web servers under Yasara software. Web servers and foldx predicted that two mutations, Q35L and H9M, would stabilize the structure. The web server Polyphen-2 predicted that these two mutations would not have a damaging effect on enzyme function. To further confirm these two mutations, molecular dynamics simulations were performed. The results of RMSD and RMSF and the radius of gyrus and hydrophobicity also showed that these mutations may cause increase the stability of this enzyme.

Indigenous knowledge is a piece of unwritten information between different ethnic groups that is traditionally used in that region. Part of this indigenous knowledge is related to the different uses of tribes in the use of the environment around settlements. A significant part of this surrounding environment can be considered animals and birds. Since the study area is in a rural area and forest edge and with agricultural activities, different uses of domestic and wild animals and birds in it are of special importance. Therefore, in this research, three hundred and eighty seven entries were collected from specialized vocabulary related to animals, birds and hunt with different categories such as Domestic and wild animals, domestic and wild birds and hunting. By registering these specialized words, it can be prevented from being forgotten by the current generation who are not very interested in the dialect of Gilaki as a mother language and even future generations.

The reproductive system of men with varicocele is affected by the negative effects of oxidative stress on the testicles. In traditional medicine, the linden (Tilia platyphyllos L.) is used as a medicine to treat stomach ulcers, spasms and sedatives. Chemical compounds such as terpenoids and flavonoids have been identified in the linden. The aim of this study was to evaluate the effect of linden extract on testicular pathology of healthy and varicocele rats. In this study, 48 rats were randomly divided into 8 groups: Healthy control, healthy groups receiving linden extract (50, 100 and 200 mg / kg intragastrically, daily) alone, Infertile control (varicocele surgery), varicocele groups together with linden extract (50, 100 and 200 mg / kg intragastrically, daily). After 60 days, sperm analysis was performed and data were analyzed using one-way analysis of variance.Our results showed that sperm analysis was significantly decreased in infertile control animals compared to the normal control group. linden treatment prevented sperm changes and caused a significant increase in sperm parameters of infertile animals and decreased varicocele damage and protected the natural structure of the testis. Our results suggest that linden acts as a potent antioxidant against varicocele-induced damage in the rat.

In this study, the NMRI adult male mice were anesthetized. To induce the Parkinson's animal model, a 22 gauge cannula was placed into the left Substantia Nigra pars compacta and then 6-hydroxydopamine was infused to Substantia Nigra pars compacta through a 30-gauge cannula. The group control1 received saline on the left side of the Substantia Nigra pars compacta.Then, to investigate the effect of the Naringenin, group control2 received distilled water and other groups received Naringenin via gavage for two weeks, and apomorphine induced rotation, catalepsy, and behavioral tests were assessed in all groups. Hematoxylin and eosin staining was performed and the percentage of the neurons on the left side of the Substantia Nigra pars compacta were calculated. In this study, in cell culture model, dopaminergic-like neurons cultured in DMEM medium were counted, and cells were used and incubated to evaluate the effect of naringinin against 6-hydroxy dopamine. Concentrations were 50 for 6-hydroxy dopamine solution and 0.25, 0.1 and 0.01 for NAR solution. Finally, cell viability was assessed using MTT and trypan blue methods.

6-Hydroxy dopamine increased catalepsy and contralateral turns compared to the control group. Naringin reduced catalapsy and contralateral turns, it reduced anxiety and depressive-like behaviours besides that it increased swimming time and locomotor activity compared to the control group.

it seems that Naringin is a therapeutic option for neurodegenerative disorders, such as Parkinson's disease.