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1.
Climate change may cause shifts in the natural range of species especially for those that are geographically restricted and/or endemic species. In this study, the spatial distribution of five endemic and threatened species belonging to the genus Onosma (including O. asperrima, O. bisotunensis, O. kotschyi, O. platyphylla, and O. straussii) was investigated under present and future climate change scenarios: RCP2.6 (RCP, representative concentration pathway; optimistic scenario) and RCP8.5 (pessimistic scenario) for the years 2050 and 2080 in Iran. Analysis was conducted using the maximum entropy (MaxEnt) model to provide a basis for the protection and conservation of these species. Seven environmental variables including aspect, depth of soil, silt content, slope, annual precipitation, minimum temperature of the coldest month, and annual temperature range were used as main predictors in this study. The model output for the potential habitat suitability of the studied species showed acceptable performance for all species (i.e., the area under the curve (AUC)>0.800). According to the models generated by MaxEnt, the potential current patterns of the species were consistent with the observed areas of distributions. The projected climate maps under optimistic and pessimistic scenarios (RCP2.6 and RCP8.5, respectively) of 2050 and 2080 resulted in reductions and expansions as well as positive range changes for all species in comparison to their current predicted distributions. Among all species, O. bisotunensis showed the most significant and highest increase under the pessimistic scenario of 2050 and 2080. Finally, the results of this study revealed that the studied plant species have shown an acute adaptability to environmental changes. The results can provide useful information to managers to apply appropriate strategies for the management and conservation of these valuable Iranian medicinal and threatened plant species in the future.  相似文献   
2.
There is a wide variety of cancer types yet, all share some common cellular and molecular behaviors. Most of the chemotherapeutic agents used in cancer treatment are designed to target common deregulated mechanisms within cancer cells. Many healthy tissues are also affected by the cytotoxic effects of these chemical agents. Fucoidan, a natural component of brown seaweed, has anti-cancer activity against various cancer types by targeting key apoptotic molecules. It also has beneficial effects as it can protect against toxicity associated with chemotherapeutic agents and radiation. Thus the synergistic effect of fucoidan with current anti-cancer agents is of considerable interest. This review discusses the mechanisms by which fucoidan retards tumor development, eradicates tumor cells and synergizes with anti-cancer chemotherapeutic agents. Challenges to the development of fucoidan as an anti-cancer agent will also be discussed.  相似文献   
3.
The eukaryotic expression plasmid of M2e-Hsp70 is a candidate M2e-based DNA vaccine. In order to evaluate the immunization potential of this construct, Specific Pathogen Free chickens were immunized either intramuscularly or orally. Mutant Salmonella typhimurium was used as carrier for oral delivery of the M2e-Hsp70 construct. M2e-specific humoral and cellular responses were tested by ELISA and Lymphocyte Proliferation Assay, respectively. Our results indicate that both humoral and cellular immune responses are conferred against M2e-Hsp70 plasmid in either of the intramuscular or oral routes of administration; however, these responses are significantly higher in intramuscular injection in contrast to oral administration. When it comes to mass vaccination of commercial chicken flocks oral administration is preferred due to the ease of application as well as its capability of eliciting mucosal, humoral and cellular immune responses; so measurements should be taken to improve the immunization potency of our orally delivered DNA vaccine.  相似文献   
4.
Background: Pseudomonas aeruginosa is one of the opportunistic pathogens causing frequent hospital-acquired life-threatening infections in mechanically ventilated patients. The most significant virulence factor of P. aeruginosa is T3SS. PcrV is an important structural protein of the T3SS. Methods:In the current investigation, a recombinant scFv mAb against the PcrV protein was expressed in EnBase® (fed-batch) cultivation mode. The pETiteTM N-His SUMO Kan vector, including anti-PcrV scFv gene, was transformed into Escherichia coli (BL21) cells. The expression and solubility of anti-PcrV scFv protein were investigated at two different temperatures (25 °C and 30 °C) and at different induction times (4, 6, 8, 12, and 24 hours). Results:Increased efficiency was achieved by EnBase® compared to LB broth; owing to the slow release of glucose, the maximum level of solubility and total protein expression was observed in EnBase® cultivation system at 30 °C and 24 h post induction. Furthermore, IC50 for anti-PcrV scFv protein was determined to be approximately 7 μg/mL. Conclusion:Anti-PcrV scFv produced in this study showed promising in vitro results, protecting RBC from lysis by P. aeruginosa (exoU+). Key Words: Fed Batch, recombinant protein, Pseudomonas aeruginosa, scFv  相似文献   
5.
International Aquatic Research - The aim of this study was to use apple peel extract (APE) as antioxidant for inhibition of lipid and protein oxidation in rainbow trout (Oncorhynchus mykiss) mince...  相似文献   
6.
Despite the importance of pod removal in the seeds of annual medics, there have been few studies carried out in this area. In this research, the role of pod removal in growth and biochemical enzyme activities was examined in three annual medic species during drought stress and subsequent recovery. This study was carried out as a factorial experiment based on a completely randomized design. The treatments were carried out on annual medic species of three levels: Medicago rigidula, M. scutellata, M. polymorpha, presence or removal of the pod and water stress. Water stress was split into the following four levels: 100%, 80%, 60%, and 40% field capacity (FC) during the stress period. The results showed that drought stress and subsequent recovery increased proline content and antioxidant enzyme activity. The highest proline content and antioxidant enzyme activity was observed in M. Scutellata. However, the rate at which proline increased, decreased at 40% FC whereas the antioxidant enzyme reached their highest activity at 40% FC. The antioxidant enzymes’ activity and proline content without the pod experiment were significantly higher than with the pod experiment. Since the activation of an antioxidant system and the increasing of the proline content helps the plants with stress induced damages, our results indicated that elimination of pods of annual medics before sowing helps seedlings to perform better under drought stress. This data is useful to gain a better understanding of the physiological basis of the changes in drought resistance as well as the crop breeding projects.  相似文献   
7.
8.
A seroepidemiology study of Neospora caninum was conducted in Mashhad area, Khorasan province, Iran on 337 cattle from 30 dairy using ELISA. All herds had seropositive cattle and antibodies were formed in 46% of the cattle. Abortion was significantly associated with seropositivity of cattle. The highest risk of abortion was observed in the 1-2-year-old cows. Our results indicate that Neospora infection is widespread in Iran.  相似文献   
9.
The aim of this study was to evaluate the effects of Bacillus subtilis and Bacillus licheniformis on growth, gut microbiota, and digestive enzyme activities of Artemia urmiana. Three diets containing 102 (T1), 104 (T2), 106 (T3) CFU of probiotics/g feed, and a control diet (C) without probiotic were used through a completely randomized design (treatments with triplicates). Twelve plastic tanks with the capacity of 60- l and density of 20 nauplii/ml were used and the trial continued for 15?days. Results showed that probiotics significantly increased the total length of A. urmiana (P?<?0.05). Although the total aerobic gastrointestinal bacteria count showed no significant differences among the treatments, the total Bacillus count significantly increased in experiments (P?<?0.05). The ratio of TCBS to total aerobic bacteria count was significantly lower in T1 (0.31?±?0.05), T2 (0.27?±?0.15), and T3 (0.25?±?0.05) compared to the control (0.76?±?0.34) (P?<?0.05). The probiotics were able to increase the protease and amylase activities (P?<?0.05). No significant effect on lipase activity. The study determined T2 and T3 as the most effective treatments for improving growth, bacterial flora, and digestive enzyme activities. As less probiotic needed in T2, using 104 bacteria per g diet is recommended for rearing Artemia up to the maturity stage.  相似文献   
10.
1. The avian embryo is an excellent model for studying embryology and the production of pharmaceutical proteins in transgenic chickens. Furthermore, chicken stem cells have the potential for proliferation and differentiation and emerged as an attractive tool for various cell-based technologies.

2. The objective of these studies is the derivation and culture of these stem cells is the production of transgenic birds for recombinant biomaterials and vaccine manufacture, drug and cytotoxicity testing, as well as to gain insight into basic science, including cell tracking.

3. Despite similarities among the established chicken stem cell lines, fundamental differences have been reported between their culture conditions and applications. Recent conventional protocols used for expansion and culture of chicken stem cells mostly depend on feeder cells, serum-containing media and static culture.

4. Utilising chicken stem cells for generation of cell-based transgenic birds and a variety of vaccines requires large-scale cell production. However, scaling up the conventional adherent chicken stem cells is challenging and labour intensive. Development of a suspension cell culture process for chicken embryonic stem cells (cESCs), chicken primordial germ cells (PGCs) and chicken induced pluripotent stem cells (ciPSCs) will be an important advance for increasing the growth kinetics of these cells.

6. This review describes various approaches and suggestions to achieve optimal cell growth for defined chicken stem cells cultures and use in future manufacturing applications.  相似文献   

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