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Behrouz Rafiei Fatemeh Ahmadi Ghomi Leila Ardebili Majid Sadeghifar Seyed Hojjat Khodaparast Sharifi 《Soil & Sediment Contamination》2012,21(6):768-787
Concentrations of four metals (Cu, Zn, Pb, and Cd) in the sediments of the Anzali Lagoon in the northern part of Iran were determined to evaluate the level of contamination and spatial distribution. The sediments were collected from 21 locations in the lagoon. At each lagoon site a core, 60 cm long, was taken. The ranges of the measured concentrations in the sediments are as follows: 17–140 mg kg?1 for Cu, 20–113 mg kg?1 for Zn, 1–37 mg kg?1 for Pb and 0.1–3.5 mg kg?1 for Cd in surficial (0-20 cm) and 16–87 mg kg?1 for Cu, 28.5–118 mg kg?1 for Zn, 3–20 mg kg?1 for Pb and 0.1–3.5 mg kg?1 for Cd in deep (40–60 cm) sediments. The results of the geoaccumulation index (Igeo) show that Cd causes moderate to heavy pollution in most of the study area. Environmental risk evaluation showed that the pollution in the Anzali Lagoon is moderate to considerable and the ranking of the contaminants followed the order: Cd > Cu > Pb > Zn. Some locations present severe pollution by metals depending on the sources, of which sewage outlets and phosphate fertilizers are the main sources of contaminants to the area. 相似文献
93.
Behrouz Jedari Ali Rahmani Mahmood Naderi Samad Nadri 《Journal of cellular biochemistry》2020,121(4):2818-2827
The purpose of this study was to investigate miR-7 overexpression effects on neural differentiation of mesenchymal stem cells (MSCs) on both two-dimensional (2D) and three-dimensional (3D) culture systems. We upregulated miR-7 through lentiviral vector in trabecular meshwork MSCs (TMMSCs) and polymers of poly l -lactic acid/polycaprolactone fibrous scaffold were fabricated by electrospinning and characterized using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). Neural markers expression was evaluated through quantitative-polymerase chain reaction (q-PCR) and immunostaining. The results showed that the high percentage of cell transduction (84.9%) and miR-7 expression (folds: 677.93 and 556.4) was detected in TMMSCs-miR-7(+). SEM and FTIR established the fabrication of the hybrid scaffold. q-PCR analysis showed that on days 14 and 21 of transduction, the expression level of Nestin and glial fibrillary acidic protein (GFAP) genes were significantly higher in the scaffold (3D) compared with tissue culture polystyrene (2D) culture. The expression of microtubule-associated protein-2 (MAP-2) and GFAP genes in TMMSCs-miR-7(+) cells were significantly higher than those miR-7(−) cells after 21 days of cell culture. Also, MAP-2 and Nestin proteins were detected in TMMSCs-miR-7(+) cells. Our results demonstrate that miR-7 is involved in neural differentiation of TMMSCs and scaffold can improve differentiate into glial and neural progenitor cells. These findings provided some information for future use of microRNAs and scaffold in tissue engineering and cell therapy for neurological diseases. 相似文献
94.
Lucienne A. Vonk Robert Jan Kroeze Behrouz Zandieh Doulabi Roel J. Hoogendoorn ChunLing Huang Marco N. Helder Vincent Everts Ruud A. Bank 《Matrix biology》2010,29(3):209-218
Cartilage is a tissue with only limited reparative capacities. A small part of its volume is composed of cells, the remaining part being the hydrated extracellular matrix (ECM) with collagens and proteoglycans as its main constituents. The functioning of cartilage depends heavily on its ECM. Although it is known that the various (fibro)cartilaginous tissues (articular cartilage, annulus fibrosus, nucleus pulposus, and meniscus) differ from one each other with respect to their molecular make-up, remarkable little quantitative information is available with respect to its biochemical constituents, such as collagen content, or the various posttranslational modifications of collagen. Furthermore, we have noticed that tissue-engineering strategies to replace cartilaginous tissues pay in general little attention to the biochemical differences of the tissues or the phenotypical differences of the (fibro)chondrocytes under consideration. The goal of this paper is therefore to provide quantitative biochemical data from these tissues as a reference for further studies. We have chosen the goat as the source of these tissues, as this animal is widely accepted as an animal model in orthopaedic studies, e.g. in the field of cartilage degeneration and tissue engineering. Furthermore, we provide data on mRNA levels (from genes encoding proteins/enzymes involved in the synthesis and degradation of the ECM) from (fibro)chondrocytes that are freshly isolated from these tissues and from the same (fibro)chondrocytes that are cultured for 18 days in alginate beads. Expression levels of genes involved in the cross-linking of collagen were different between cells isolated from various cartilaginous tissues. This opens the possibility to include more markers than the commonly used chondrogenic markers type II collagen and aggrecan for cartilage tissue-engineering applications. 相似文献
95.
Behrouz?Ehsani?MoghaddamEmail author Rosna?Mat?Taha 《In vitro cellular & developmental biology. Plant》2005,41(4):465-469
Summary The present study diseusses the results of cytological studies of two kinds of sugar beet callus, i.e., embryogenic and non-embryogenic
tissues. The calluses were produced through culture of secondary leaves on Murashige and Skoog medium containing two hormone
combinations. One week after transfer of calluses onto fresh medium, their cells were viewed using electron microscopy and
an image analyzer. Observations showed that cells of the two callus types had considerable differences in cell structure and
various organelles. Of note were the high amount of polyploidization, rough endoplasmic reticulum, polysome, poly-nucleolus,
and incomplete cell wall together with abnormal partitioning in non-embryogenic cells, as compared to embryogenic cells. In
contrast, vacuolation of cytoplasm, perfect cell wall and partitioning structure, and the high proportion of nucleus/cytoplasm
area were recognized in embryogenic cells. 相似文献
96.
Fahham N Sardari S Ostad SN Vaziri B Ghahremani MH 《Journal of cellular biochemistry》2010,111(6):1598-1606
The tumor suppressor p16(INK4a) has earned widespread attention in cancer studies since its discovery as an inhibitor of cyclin-dependent kinases (CDKs) 4/6. Structurally, it consists of four complete ankyrin repeats, believed to be involved in CDK4 interaction. According to the previous disparities concerning the importance of domains and inactivating mutations in p16, we aimed to search for the domain possessing the functional properties of the full length protein. Upon our in silico screening analyses followed by experimental assessments, we have identified the novel minimum functional domain of p16 to be the C-terminal half including ankyrin repeats III, IV and the C-terminal flanking region accompanied by loops 2 and 3. Transfection of this truncated form into HT-1080 human fibrosarcoma cells, lacking endogenous p16, revealed that it is able to inhibit cell growth and proliferation equivalent to p16(INK4a). The functional analysis showed that this fragment like p16 can interact with CDK4/6, block the entry into S phase of the cell cycle and suppress growth as indicated by colony formation assay. Identification of p16 minimum functional domain can be of benefit to the future peptidomimetic drug design as well as gene transfer for cancer therapy. 相似文献
97.
N Behrouz A Defossez A Delacourte M Mazzuca 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1990,310(11):539-544
Amyloid deposits constituted with the beta amyloid protein A4 (beta PA4) have been recently immunodetected in skin and intestine wall of Alzheimer's patients. These findings support the hypothesis of an extraneuronal origin of the beta PA4. Until now, these amyloid deposits had not been observed in the white matter of Alzheimer's brains. Using an antiserum against the 1-10 N Ter subsequence of the beta PA4, we immunodetected amyloid deposits in white matter sections of Alzheimer's brains, pretreated with periodic acid. The immunolabelled amyloid substance was associated with capillaries. These original findings are in good agreement with the vascular origin of the beta PA4. 相似文献