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51.
Rodrigues Vereena Kumar Amit Gokul Sivaraman Verma Ram S. Rahman Laiq ur Sundaresan Velusamy 《In vitro cellular & developmental biology. Plant》2020,56(4):526-537
In Vitro Cellular & Developmental Biology - Plant - An efficient in vitro propagation and synthetic seed production protocol was established for the conservation of Decalepis salicifolia (Bedd.... 相似文献
52.
Inamur Rahman Lina Fang Zhang Wei Xiaodong Zheng Lei Huang 《Preparative biochemistry & biotechnology》2020,50(6):598-606
AbstractHuman basic fibroblast growth factor (hbFGF) is involved in a wide range of biological activities that affect the growth, differentiation, and migration. Due to its wound healing effects and therapy, hbFGF has the potential as therapeutic agent. Therefore, large-scale production of biologically active recombinant hbFGF with low cost is highly desirable. However, the complex structure of hbFGF hinders its high-level expression as the soluble and functional form. In the present study, an efficient, cost-effective, and scalable method for producing recombinant hbFGF was developed. The modified collagen-like protein (Scl2-M) from Streptococcus pyogenes was used as the fusion tag for producing recombinant hbFGF for the first time. After optimization, the expression level of Scl2-M-hbFGF reached approximately 0.85?g/L in the shake flask and 7.7?g/L in a high cell-density fermenter using glycerol as a carbon source. Then, the recombinant Scl2-M-hbFGF was readily purified using one-step acid precipitation and the purified Scl2-M-hbFGF was digested with enterokinase. The digested mixture was further subject to ion-exchange chromatography, and the final high-purity (96%) hbFGF product was prepared by freeze-drying. The recovery rate of the whole purification process attained 55.0%. In addition, the biological activity of recombinant hbFGF was confirmed by using L929 and BALB/c3T3 fibroblasts. Overall, this method has the potential for large scale production of recombinant hbFGF. 相似文献
53.
Md Robiul Karim Farzana Islam Rume Abu Nasar Md Aminoor Rahman Zhenjie Zhang Junqiang Li Longxian Zhang 《The Journal of eukaryotic microbiology》2020,67(4):427-435
To determine the occurrence and genotypes of Enterocytozoon bieneusi in captive mammals at Bangladesh National Zoo and to assess their zoonotic significance, 200 fecal samples from 32 mammalian species were examined using a nested PCR and sequencing of internal transcribed spacer (ITS) gene. Enterocytozoon bieneusi was detected in 16.5% (33/200) of the samples. Seven different ITS genotypes were identified, including two known genotypes (D and J) and five new ones (BAN4 to BAN8). Genotype D was the most common genotype being observed in 19 isolates. In phylogenetic analysis, four genotypes (D, BAN4, BAN5, and BAN6), detected in 30 isolates (90.9%), belonged to Group 1 having zoonotic potential. The sequence of genotype J found in a Malayan pangolin was clustered in so‐called ruminant‐specific Group 2. The other two genotypes BAN7 and BAN8 were clustered in primate‐specific Group 5. To our knowledge, this is the first report of molecular characterization of E. bieneusi in Bangladesh, particularly in captive‐bred wildlife in this country. The potentially zoonotic genotypes of E. bieneusi are maintained in zoo mammals that may transmit among these animals and to the humans through environmental contamination or contact. 相似文献
54.
Amin Ghafuri-Esfahani Rahman Shokri Athar Sharifi Lida Shafiee Roya Khosravi 《Preparative biochemistry & biotechnology》2020,50(8):834-841
AbstractSeveral factors may affect erythropoietin (EPO) sugar structures including designing cell culture procedure, pH, concentration of additives, dissolved oxygen, and other physicochemical parameters. In this study, we investigated the influence of changes in effective parameters and compounds on the growth rate of Chinese hamster ovary cell (CHO) cells producing recombinant EPO. Cell culture was performed at different temperature, buffering conditions, and varied concentrations of additives such as pyruvic acid, insulin, GlutaMAX, and sodium butyrate. Results indicated that the optimal temperature and pH were 37?°C and 7.2, respectively. Also, optimal concentrations for pyruvic acid, butyrate, glutamate, and insulin were obtained to be 20?mM, 1?mM, 2?mM, and 40?μg/mL, respectively. Then, cell culture was performed in microcarrier-coated spinner flasks under the optimized condition. The results showed recombinant human EPO (rhEPO) production with adequate purity. Optimization of physicochemical conditions and culture media are important factors to improve the quantity and quality of protein products. This study showed that cell growth and recombinant EPO protein production significantly increased under the optimized conditions. The results of this research can also be used in scale-up to increase the efficiency of EPO production. Abbreviations: EPO: erythropoietin; CHO cell: Chinese hamster ovary cell; rhEPO: recombinant human EPO; DMEM: modified eagle’s medium; FBS: fetal bovine serum; SDS-PAGE: sodium dodecyl sulfate–polyacrylamide gel electrophoresis; IGF-1: insulin-like growth factor 1 相似文献
55.
Alam Md. Rabiul Mahmood Hossain Rahman Md. Masudur 《Wetlands Ecology and Management》2020,28(3):449-460
Wetlands Ecology and Management - Mangroves adaptive plasticity in the changing environmental conditions is of vital importance for conservation management. Genetic diversity of mangrove brings... 相似文献
56.
Mahendran Ganesan Kumar Deepak Verma Sanjeet Kumar Chandran Ashish Warsi ·Zafar Iqbal Husain Zakir Afroz Shama Rout Prasant Kumar Rahman Laiq Ur 《Plant Cell, Tissue and Organ Culture》2021,146(2):423-423
Plant Cell, Tissue and Organ Culture (PCTOC) - 相似文献
57.
58.
Md. Ashekur Rahman Md. Yeamin Hossain Sumaya Tanjin Zannatul Mawa Md. Rabiul Hasan Kazi Ahsan Habib Jun Ohtomi 《Zeitschrift fur angewandte Ichthyologie》2021,37(2):364-366
Length weight relationships (LWR) of five marine fishes were estimated from the Bay of Bengal, Bangladesh. Fish samples were collected occasionally from fisher's catch with gill net (mesh size: 3 cm) during November 2019 to October 2020. Fishing was done overnight. Total length (0.1 cm) and body weight (0.01 g) of each individual were measured. We recorded maximum total length for P. maculatus (55.0 cm) and P. parmatus (39.0 cm). 相似文献
59.
Che Mat Mohd Firdaus Mohamad Hanif Ezanee Azlina Abdul Murad Nor Azian Ibrahim Kamariah Harun Roslan Jamal Rahman 《Molecular biology reports》2021,48(2):1493-1503
Molecular Biology Reports - Despite the advancements in primary brain tumour diagnoses and treatments, the mortality rate remains high, particularly in glioblastoma (GBM). Chemoresistance,... 相似文献
60.
Chorong Park Chen Peng M. Julhasur Rahman Sherry L. Haller Loubna Tazi Greg Brennan Stefan Rothenburg 《PLoS pathogens》2021,17(1)
The antiviral protein kinase R (PKR) is an important host restriction factor, which poxviruses must overcome to productively infect host cells. To inhibit PKR, many poxviruses encode a pseudosubstrate mimic of the alpha subunit of eukaryotic translation initiation factor 2 (eIF2), designated K3 in vaccinia virus. Although the interaction between PKR and eIF2α is highly conserved, some K3 orthologs from host-restricted poxviruses were previously shown to inhibit PKR in a species-specific manner. To better define this host range function, we compared the sensitivity of PKR from 17 mammals to inhibition by K3 orthologs from closely related orthopoxviruses, a genus with a generally broader host range. The K3 orthologs showed species-specific inhibition of PKR and exhibited three distinct inhibition profiles. In some cases, PKR from closely related species showed dramatic differences in their sensitivity to K3 orthologs. Vaccinia virus expressing the camelpox virus K3 ortholog replicated more than three orders of magnitude better in human and sheep cells than a virus expressing vaccinia virus K3, but both viruses replicated comparably well in cow cells. Strikingly, in site-directed mutagenesis experiments between the variola virus and camelpox virus K3 orthologs, we found that different amino acid combinations were necessary to mediate improved or diminished inhibition of PKR derived from different host species. Because there is likely a limited number of possible variations in PKR that affect K3-interactions but still maintain PKR/eIF2α interactions, it is possible that by chance PKR from some potential new hosts may be susceptible to K3-mediated inhibition from a virus it has never previously encountered. We conclude that neither the sensitivity of host proteins to virus inhibition nor the effectiveness of viral immune antagonists can be inferred from their phylogenetic relatedness but must be experimentally determined. 相似文献