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Partial characterization of phytoplasmas associated with lettuce and wild lettuce phyllodies in Iran
Phytoplasmas associated with lettuce phyllody (LP) and wild lettuce phyllody (WLP) in southern Iran were partially characterized by molecular analyses and host-range studies. Agents of both diseases were transmitted by Neoaliturus fenestratus , a leafhopper colonizing lettuce and wild lettuce, to lettuce, wild lettuce, sowthistle and periwinkle, but not to safflower, sunflower, calendula and sesame. Both phytoplasmas induced bud proliferation, virescence, phyllody and witches' broom in infected plants. Total DNA extracted from infected lettuce and wild lettuce or from vector tissues was subjected to PCR using phytoplasma-specific primer pair P1/P7 or nested PCR using P1/P7 followed by R16F2n/R16R2. PCR product of nested PCR (1·2 kbp) was subjected to restriction fragment length polymorphism (RFLP). RFLP analysis of nested PCR product identified the LP, WLP and N. fenestratus -associated phytoplasmas as members of the pigeon pea witches' broom group, 16SrIX. Phylogenetic analysis of the 16S rRNA gene sequence also clustered LP and WLP phytoplasmas with other known members of the 16SrIX group. While no significant differences could be detected between LP and WLP phytoplasmas, both isolates differed from Lebanese wild lettuce phyllody in molecular properties. 相似文献
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Wedeen VJ Rosene DL Wang R Dai G Mortazavi F Hagmann P Kaas JH Tseng WY 《Science (New York, N.Y.)》2012,335(6076):1628-1634
The structure of the brain as a product of morphogenesis is difficult to reconcile with the observed complexity of cerebral connectivity. We therefore analyzed relationships of adjacency and crossing between cerebral fiber pathways in four nonhuman primate species and in humans by using diffusion magnetic resonance imaging. The cerebral fiber pathways formed a rectilinear three-dimensional grid continuous with the three principal axes of development. Cortico-cortical pathways formed parallel sheets of interwoven paths in the longitudinal and medio-lateral axes, in which major pathways were local condensations. Cross-species homology was strong and showed emergence of complex gyral connectivity by continuous elaboration of this grid structure. This architecture naturally supports functional spatio-temporal coherence, developmental path-finding, and incremental rewiring with correlated adaptation of structure and function in cerebral plasticity and evolution. 相似文献
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Farzad Rajaei Neda Abedpour Mojdeh Salehnia Hassan Jahanihashemi 《Iranian Biomedical Journal》2013,17(4):200-205
Background
: Oocyte cryopreservation is one of the most important topics in the field of assisted reproductive technology to preserve women fertility, but relationship between cryopreservation and apoptosis is still a matter of debate. The present study was aimed to investigate the effects of vitrification on apoptosis in mouse oocytes by Cryotop method. Method: A total of 200 germinal vesicle (GV) and 200 metaphase II (MII) oocytes were obtained from ovaries and fallopian tubes of NMRI mice, respectively and divided into control and experimental groups. Oocytes in experimental group were vitrified by Cryotop using vitrification medium and were kept in liquid nitrogen for one month. The survival rate of oocytes was evaluated after 2 hour incubation time. Then, the oocyte apoptosis was evaluated by TUNEL technique and compared with those in control group. The data was compared statistically using SPSS software and chi-square test. Results: The survival rates of vitrified GV (93%) and MII oocytes (88%) showed a significant decrease compared with the control group (P<0.05), but there was no significant difference in survival rate of both vitrified oocyte groups. The incidence of apoptosis in vitrified and control GV oocytes showed no significant difference (13% vs. 7%), but the rate of apoptosis in vitrified MII oocytes increased significantly not only in comparison with MII control group (25% vs. 5%) but also with vitrified GV oocytes (P<0.05). Conclusion: The results indicate that vitrification increases apoptosis in mouse MII oocytes and apoptosis may play a role in MII oocyte injury after vitrification. Key Words: Vitrification, Apoptosis, Oocytes 相似文献
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Neda Ghorbanzadeh Ali Salehi Hassan Pourbabaei Ali Ashraf Soltani Tolarod Seyed Jalil Alavi 《林业研究》2019,(2):679-688
Microbial indices and their spatial patterns are strongly affected by environmental factors. Spatial variability of soil properties is one of the most important causes of variability in soil microbial indices. This research was conducted in the Caspian forest to assess spatial variabilities and frequency distributions of microbial properties.Ninety soil samples were taken using a grid sampling design 40 9 40 m. Microbial indices, organic carbon,nitrogen and pH were determined. Soil variable distributions showed that microbial indices had abnormal distributions. Logarithmic transformation produced normal distribution. Spatial continuity using geostatistical(variogram) was studied and maps obtained by point kriging.The variograms revealed the presence of spatial autocorrelation. The results indicate that spatial dependence of soil microbial indices was affected by non-intrinsic factors and forest management procedures. The maps show that soil microbial indices and soil properties have spatial variability. The spatial pattern of microbial indices was correlated to organic carbon and nitrogen. 相似文献
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This study aims to investigate the land cover changes in relation to traditional utilization and livestock grazing, socioeconomic development, and demographic changes during recent decades in a forested watershed in the southern Zagros, Iran. Data on land cover change were collected through stereo interpretation with digital photogrammetric techniques applied to sets of scanned aerial photographs from 1969 and 1993 with a systematic grid of sample plots provided by GIS techniques. Efforts were made to mitigate errors in the interpretation. Field data were gathered in 2003 from woodland inventory, biophysical, and demographic data and in 2006 from interviews. The results show stability in crown cover density (%) and in the number of large trees, and an increase in the woodland class. The results may be related to a change in woodland utilization. Socioeconomic development, decrease in human and livestock population, and a change in the type of livestock have influenced the traditional pattern. Steep slopes partially limit human accessibility to woodland resources. Around 54% of the oak trees are in coppice form and natural regeneration of the trees is rare. Overgrazing and seed gathering have a negative effect on regeneration and endanger the future survival of the woodland. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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Majid Salehi Ahmad Vaez Mahdi Naseri-Nosar Saeed Farzamfar Arman Ai Jafar Ai Shima Tavakol Mehrdad Khakbiz Somayeh Ebrahimi-Barough 《Fibers and Polymers》2018,19(1):125-134
In the present study, naringin, a flavonoid isolated from the grape and citrus fruit species, was incorporated with poly(ε-caprolactone)/gelatin composite mats in order to develop a potential wound dressing. The composite mats were prepared by electrospinning of poly(ε-caprolactone)/gelatin (1:1 (w/w)) solution incorporated with 1.50 %, 3 % and 6 % (w/w) of naringin. The electrospun mats were evaluated regarding their morphology, contact angle, water-uptake capacity, water vapor transmission rate, tensile properties, drug release, cellular response and in vivo wound healing activity. The study showed that after 2 weeks, the full-thickness excisional wounds of Wistar rats treated with the naringin-loaded dressings achieved a wound closure of higher than 94 % and the dressing containing 6 % (w/w) naringin had almost 100 % wound closure. The sterile gauze, as the control group, showed nearly 86 % of wound closure after this period of time. Our results provided evidence that supports the possible applicability of naringin-loaded wound dressing for successful wound treatment. 相似文献
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Asadi F Rostami A Asadian P Pourkabir M 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(2):188-191
BACKGROUND: Serum biochemical and hematologic parameters are important in the management of game species in Iran, such as Persian squirrels. OBJECTIVE: The purpose of this study was to establish baseline serum chemistry and hematology values in Persian squirrels (Sciurus anomalus) and describe blood cell morphology and the electrophoretic pattern of hemoglobin. METHODS: Blood samples were collected from 30 Persian squirrels (Sciurus anomalus) maintained in captivity in the Tehran Zoo. Blood was placed into EDTA and serum clot tubes and analyzed using standard manual hematology and biochemical techniques. Hemoglobin electrophoresis was done on cellulose acetate paper strips. RESULTS: Minimum, maximum, and median values were obtained for 11 hematologic and 12 serum chemistry parameters. Hypersegmented neutrophils were observed frequently. We did not find basophils or band neutrophils. Hemoglobin electophoresis resulted in a band slightly anodal to that of human hemoglobin A. CONCLUSION: Biochemical and hematologic values in Persian squirrels were comparable to those of related species, and may be used as a standard profile for healthy Persian squirrels kept in captivity. 相似文献