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271.
Relationships between environmental variables and vegetation across mountain wetland sites,N. Iran 总被引:1,自引:0,他引:1
Asghar Kamrani Adel Jalili Alireza Naqinezhad Farideh Attar Ali Asghar Maassoumi Sue C. Shaw 《Biologia》2011,66(1):76-87
The mountain wetlands studied represent a unique habitat on the southern slopes of the Alborz mountain range, the second largest
range in Iran. In comparison with other parts of this range the western section is ecologically and botanically unknown. Floristic
and vegetation variation were assessed using diverse environmental variables along a broad altitudinal span (350 m to 3200
m a.s.l.). Using both statistical and ordination analyses floristic variation was assessed on three defined altitudinal belts
which were delimited based on Alborz macro-climatic boundaries. The distribution of individual wetland plant species, of phytogeographic
elements and of life-forms all differ among altitudinal belts. This result is also shown in both direct and indirect analyses
of ordinations. The proportion of geophytes significantly increases with altitude and geophytes are very well represented
in the upper altitudinal belt. The number of species of a narrow phytogeographical distribution (e.g. endemics) increases
with altitude, soil pH and EC declined with altitude. The first axis of DCA ordination with passively projected environmental
variables indicates that, organic matter and concentration of Fe2+ are increased toward higher altitude. The second axis of ordination is related to both soil texture and slope inclination.
The distribution of species in the CCA species plot is also close to the distribution of those in the DCA ordination. This
study indicates that altitude and slope together with other dependent environmental variables (pH, EC, Ca2+ and soil texture) are the main ecological factors controlling species distribution across the Western Alborz wetland sites. 相似文献
272.
Pourya Nasirmoghadas Akbar Mousakhani Farahnaz Behzad Nasrin Beheshtkhoo Ali Hassanzadeh Marzieh Nikoo Mohsen Mehrabi Mohammad Amin Jadidi Kouhbanani 《Biotechnology progress》2021,37(2):e3070
Cancer has been one of the most significant causes of mortality, worldwide. Cancer immunotherapy has recently emerged as a competent, cancer-fighting clinical strategy. Nevertheless, due to the difficulty of such treatments, costs, and off-target adverse effects, the implementation of cancer immunotherapy described by the antigen-presenting cell (APC) vaccine and chimeric antigen receptor T cell therapy ex vivo in large clinical trials have been limited. Nowadays, the nanoparticles theranostic system as a promising target-based modality provides new opportunities to improve cancer immunotherapy difficulties and reduce their adverse effects. Meanwhile, the appropriate engineering of nanoparticles taking into consideration nanoparticle characteristics, such as, size, shape, and surface features, as well as the use of these physicochemical properties for suitable biological interactions, provides new possibilities for the application of nanoparticles in cancer immunotherapy. In this review article, we focus on the latest state-of-the-art nanoparticle-based antigen/adjuvant delivery vehicle strategies to professional APCs and engineering specific T lymphocyte required for improving the efficiency of tumor-specific immunotherapy. 相似文献
273.
Zahra Soraya Marzieh Ghollasi Raheleh Halabian Elahe Eftekhari Amin Tabasi Ali Salimi 《Biotechnology journal》2021,16(9):2100112
Over the past decades, bone defects caused by illness or trauma have been the most common traumatic injuries in humans and treatment of orthopedic infections has always been a serious challenge to experts in the world. In this project, poly L-lactic acid (PLLA) nanofibrous scaffolds were synthesized as a nontoxic, eco-friendly, and cost-effective scaffold by the electrospinning technique. Then, the impact of PLLA on the cell proliferation and osteogenic differentiation of human mesenchymal stem cells (hMSCs) was assayed in the presence and absence of donepezil hydrochloride (DH) which was prescribed in patients with Alzheimer's disease. Also, hMSCs were seeded on PLLA scaffold in the presence (PLLA-DH) and absence of 1 μg mL-1 of DH under osteogenic induction media. Osteogenic differentiation of hMSCs was assessed by specific bone-related tests including alkaline phosphatase (ALP) activity, Alizarin red and von Kossa staining, calcium content assay. Also, Osteocalcin and osteopontin were evaluated as osteogenic proteins as well as ALP, osteonectin, osteocalcin, collagen type I (Col-I) and Runx2 as osteogenic genes via immunocytochemistry (ICC) and Real-time PCR analyses. The obtained data showed the higher ALP enzyme activity and biomineralization, more intensity during von Kossa staining as well as the increase in the expression rate of osteogenic related gene and protein markers in differentiated hMSCs on PLLA-DH. In conclusion, the present study revealed that the combination of PLLA scaffold with DH provides a scope to develop a suitable matrix in bone tissue engineering applications. 相似文献
274.
Maedeh Jafari Peyman Mohammadzadeh Jahani Maral Choopanizadeh Marzieh Jamalidoost Bahman Pourabbas 《Biomarkers》2020,25(2):171-178
AbstractPurpose: Given the challenge in the diagnosis of bacterial meningitis (BM), we assessed different cytokines in the cerebrospinal fluid (CSF) of antibiotics pre-treated patients.Materials and methods: Laboratory tests and polymerase chain reaction (PCR) were performed for 480 CSF samples from children (2 m to 14 y), suspicious to meningitis and pre-treated with antibiotics, to detect bacterial and viral aetiologies. Sixty-one CSF were included and the levels of 13 cytokines such as IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-13, IL-17A, IL-17F, IL-21, IL-22, IFN-γ and TNF-α were measured using flow-cytometry.Results: All bacterial cultures were negative, but 29 and eight CSF were positive for bacterial and viral agents by PCR. IL-6, IL-10 and IFN-γ were significantly up-regulated in BM. T helper (Th) subset cytokines showed significant upregulation of Th1, Th2, Th17, Th22 and Tfh cytokines in BM. Common Th subsets cytokines (IL-6, IL-10 and TNF-α) were significantly different between the study groups. ROC curve analysis revealed good AUC for common Th related cytokines in discriminating BM.Conclusions: In pre-treated BM patients with negative bacterial cultures, cytokines IL-6, IL-10 and IFN-γ can predict BM which could be beneficial for rapid diagnosis and treatment to decrease the sequela of the disease. 相似文献
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277.
Marzieh Safari Ali Sorooshzadeh Ahmad Asgharzadeh Saeed Saadat 《Bioremediation Journal》2013,17(4):201-211
Batch experiments were performed to determine the cadmium absorption capacity of two plant growth–promoting rhizobacteria at different pH levels and in different cadmium concentrations. Comparison of the mean metal removal from two species of bacteria studied showed that Pseudomonas florescence is the superior species for removing cadmium at all cadmium concentrations. The maximum cadmium absorption by P. florescence and P. putida were at 5 mg/L of cadmium concentration in pH 6 and 7, respectively. The applicability of the Langmuir and Freundlich isotherm models was surveyed. Comparison of two isotherm parameters (Q m and a) further confirmed that P. fluorescence was better at binding cadmium ions (52.6 and 7.7 mg/g, respectively). Adsorption reaction also was considered by Fourier transform infrared (FTIR) spectroscopy. The FTIR analysis implied that the principal functional sites in the bacterial cell walls were phosphoryl and hydroxyl, carboxyl, amide I, amide II, and amine groups. 相似文献