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81.
Fibrella aestuarina BUZ 2(T) is the type strain of the recently characterized genus Fibrella. Here we report the draft genome sequence of this strain, which consists of a single scaffold representing the chromosome (with 11 gaps) and a 161-kb circular plasmid. 相似文献
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Khanahmad H Noori Daloii MR Shokrgozar MA Azadmanesh K Niavarani AR Karimi M Rabbani B Khalili M Bagheri R Maryami F Zeinali S 《Biochemical and biophysical research communications》2006,345(1):14-20
beta-Thalassemias are a heterogeneous group of autosomal recessive disorders, characterized by reduced or absence of the beta-globin chain production by the affected alleles. Transplantation of genetically corrected autologous hematopoietic stem cell (HSC) is an attractive approach for treatment of these disorders. Gene targeting (homologous recombination) has many desirable features for gene therapy due to its ability to target the mutant genes and restore their normal expression. In the present study, a specific gene construct for beta-globin gene replacement was constructed consisting of: two homologous stems including, upstream and downstream regions of beta-globin gene, beta-globin gene lying between hygromycin and neomycin resistant genes as positive selection markers and thymidine kinase expression cassettes at both termini as negative selection marker. All segments were subcloned into pBGGT vector. The final plasmid was checked by sequencing and named as pFBGGT. Mammalian cell line COS-7 was transfected with linear plasmid by lipofection followed by positive and negative selection. DNA of the selected cells was analyzed by PCR and sequencing to confirm the occurrence of homologous recombination. In this novel strategy gene replacement was achieved in one step and by a single construct. 相似文献
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Aso Nobakht Vakili Hedayat Bagheri Pejman Azadi 《Physiology and Molecular Biology of Plants》2018,24(4):703-710
In order to evaluate the effect of inoculation and co-cultivation media elements on transformation frequency in Petunia hybrida, modified MS media with different elements were tested on Alvan and Large Flower Alvan (LF Alvan), two local cultivars. Leaf explants of both cultivars were inoculated with Agrobacterium tumefaciens strain LBA4404 (pBI121) containing neomycin phosphotransferase (nptII) and an intron-containing β-glucuronidase (gus) genes. When medium lacking KH2PO4, NH4NO3, KNO3, and CaCl2 was used as inoculation and co-cultivation medium, a higher frequency of transformation for Alvan (22%) and LF Alvan (16%) was obtained. Kanamycin resistant plantlets were stained blue by GUS assay. Furthermore, polymerase chain reaction (PCR) analysis revealed the presence of both gus and nptII genes in all putative transformants. Finally, southern blot hybridization confirmed insertion of 1–4 copies of gus gene in transgenic plants. 相似文献
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Mohammadreza Aflatoonian Iraj Sharifi Behnaz Aflatoonian Ehsan Salarkia Ahmad Khosravi Razieh Tavakoli Oliaee Mehdi Bamorovat Abbas Aghaei Afshar Zahra Babaei Fatemeh Sharifi Moslem Taheri Soodejani Mohammad Reza Shirzadi Mohammad Mehdi Gouya Abolhassan Nadim Hamid Sharifi 《PLoS neglected tropical diseases》2022,16(4)
Negligible data are available following major social activities and environmental changes on leishmaniasis. Therefore, how interactions between these events influence cutaneous leishmaniasis (CL) risk is not well-known. This longitudinal study was undertaken to explore the impact of interventions conducted between 1971 and 2020 in Bam county, which has had the highest disease burden in Iran. Only confirmed CL cases during this period were taken into account. Data were analyzed by SPSS 22 using the X2 test to assess the significance of the difference between proportions. Moreover, we used interrupted time series (ITS) to assess the impact of three environmental events during this period. Overall, 40,164 cases of CL occurred in the past five decades. Multiple complex factors were among the leading causes that synergistically induced the emergence/re-emergence of CL outbreaks in Bam. The main factors attributed negatively to CL control were cessation of malaria spraying activity, expansion of the city spaces, and a massive earthquake creating new breeding potentials for the vectors. The highest impact on CL incidence during these years was related to the earthquake [coefficient = 17.8 (95% CI: 11.3, 22.7); p-value < 0.001]. Many factors can contribute to CL outbreaks in endemic foci. They also can cause new foci in new areas. Since humans are the single reservoir for CL in this area, early detection and effective management significantly contribute to controlling CL to reduce the disease burden. However, essential evidence gaps remain, and new tools are crucial before the disease can ultimately be controlled. Nevertheless, sustained funding and more trained task forces are essential to strengthen surveillance and case management and monitor the interventions’ impact. 相似文献
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Mehdi Sookhak Adnan Akhundzada Alireza Sookhak Mohammadreza Eslaminejad Abdullah Gani Muhammad Khurram Khan Xiong Li Xiaomin Wang 《PloS one》2015,10(1)
Wireless sensor networks (WSNs) are ubiquitous and pervasive, and therefore; highly susceptible to a number of security attacks. Denial of Service (DoS) attack is considered the most dominant and a major threat to WSNs. Moreover, the wormhole attack represents one of the potential forms of the Denial of Service (DoS) attack. Besides, crafting the wormhole attack is comparatively simple; though, its detection is nontrivial. On the contrary, the extant wormhole defense methods need both specialized hardware and strong assumptions to defend against static and dynamic wormhole attack. The ensuing paper introduces a novel scheme to detect wormhole attacks in a geographic routing protocol (DWGRP). The main contribution of this paper is to detect malicious nodes and select the best and the most reliable neighbors based on pairwise key pre-distribution technique and the beacon packet. Moreover, this novel technique is not subject to any specific assumption, requirement, or specialized hardware, such as a precise synchronized clock. The proposed detection method is validated by comparisons with several related techniques in the literature, such as Received Signal Strength (RSS), Authentication of Nodes Scheme (ANS), Wormhole Detection uses Hound Packet (WHOP), and Wormhole Detection with Neighborhood Information (WDI) using the NS-2 simulator. The analysis of the simulations shows promising results with low False Detection Rate (FDR) in the geographic routing protocols. 相似文献
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ABSTRACT: BACKGROUND: In eukaryotes, variation in gene copy numbers is often associated with deleterious effects, but may also have positive effects. For prokaryotes, studies on gene copy number variation are rare. Previous studies have suggested that high numbers of rRNA gene copies can be advantageous in environments with changing resource availability, but further association of gene copies and phenotypic traits are not documented. We used one of the morphologically most diverse prokaryotic phyla to test whether numbers of gene copies are associated with levels of cell differentiation. RESULTS: We implemented a search algorithm that identified 44 genes with highly conserved copies across 22 fully sequenced cyanobacterial taxa. For two very basal cyanobacterial species, Gloeobacter violaceus and a thermophilic Synechococcus species, distinct phylogenetic positions previously found were supported by identical protein coding gene copy numbers. Furthermore, we found that increased ribosomal gene copy numbers showed a strong correlation to cyanobacteria capable of terminal cell differentiation. Additionally, we detected extremely low variation of 16S rRNA sequence copies within the cyanobacteria. We compared our results for 16S rRNA to three other eubacterial phyla (Chroroflexi, Spirochaetes and Bacteroidetes). Based on Bayesian phylogenetic inference and the comparisons of genetic istances, we could confirm that cyanobacterial 16S rRNA paralogs and orthologs show significantly stronger conservation than found in other eubacterial phyla. Conclusions: A higher number of ribosomal operons could potentially provide an advantage to terminally differentiated cyanobacteria. Furthermore, we suggest that 16S rRNA gene copies in cyanobacteria are homogenized by both concerted evolution and purifying selection. In addition, the small ribosomal subunit in cyanobacteria appears to evolve at extraordinary slow evolutionary rates, an observation that has been made previously for morphological characteristics of cyanobacteria. 相似文献