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Xuan Wang Lorraine P. Yomano James Y. Lee Sean W. York Huabao Zheng Michael T. Mullinnix K. T. Shanmugam Lonnie O. Ingram 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(10):4021-4026
Pretreatments such as dilute acid at elevated temperature are effective for the hydrolysis of pentose polymers in hemicellulose and also increase the access of enzymes to cellulose fibers. However, the fermentation of resulting syrups is hindered by minor reaction products such as furfural from pentose dehydration. To mitigate this problem, four genetic traits have been identified that increase furfural tolerance in ethanol-producing Escherichia coli LY180 (strain W derivative): increased expression of fucO, ucpA, or pntAB and deletion of yqhD. Plasmids and integrated strains were used to characterize epistatic interactions among traits and to identify the most effective combinations. Furfural resistance traits were subsequently integrated into the chromosome of LY180 to construct strain XW129 (LY180 ΔyqhD ackA::PyadC′fucO-ucpA) for ethanol. This same combination of traits was also constructed in succinate biocatalysts (Escherichia coli strain C derivatives) and found to increase furfural tolerance. Strains engineered for resistance to furfural were also more resistant to the mixture of inhibitors in hemicellulose hydrolysates, confirming the importance of furfural as an inhibitory component. With resistant biocatalysts, product yields (ethanol and succinate) from hemicellulose syrups were equal to control fermentations in laboratory media without inhibitors. The combination of genetic traits identified for the production of ethanol (strain W derivative) and succinate (strain C derivative) may prove useful for other renewable chemicals from lignocellulosic sugars. 相似文献
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Senthilkumar Preethy Vidyasagar Devaprasad Dedeepiya Rajappa Senthilkumar Mathaiyan Rajmohan Ramalingam Karthick Hiroshi Terunuma 《International reviews of immunology》2017,36(4):220-232
Immune cell-based therapies are emerging as a promising tool to tackle malignancies, both solid tumors and selected hematological tumors. Vast experiences in literature have documented their safety and added survival benefits when such cell-based therapies are combined with the existing treatment options. Numerous methodologies of processing and in vitro expansion protocols of immune cells, such as the dendritic cells, natural killer (NK) cells, NKT cells, αβ T cells, so-called activated T lymphocytes, γδ T cells, cytotoxic T lymphocytes, and lymphokine-activated killer cells, have been reported for use in cell-based therapies. Among this handful of immune cells of significance, the NK cells stand apart from the rest for not only their direct cytotoxic ability against cancer cells but also their added advantage, which includes their capability of (i) action through both innate and adaptive immune mechanism, (ii) tackling viruses too, giving benefits in conditions where viral infections culminate in cancer, and (iii) destroying cancer stem cells, thereby preventing resistance to chemotherapy and radiotherapy. This review thoroughly analyses the sources of such NK cells, methods for expansion, and the future potentials of taking the in vitro expanded allogeneic NK cells with good cytotoxic ability as a drug for treating cancer and/or viral infection and even as a prophylactic tool for prevention of cancer after initial remission. 相似文献
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Transmission of "a" determinant variants of hepatitis B virus in immunized babies born to HBsAg carrier mothers 总被引:1,自引:0,他引:1
Velu V Saravanan S Nandakumar S Dhevahi E Shankar EM Murugavel KG Kumarasamy T Thyagarajan SP 《Japanese journal of infectious diseases》2008,61(1):73-76
Hepatitis B virus (HBV) surface antigen mutations may lead to immune escape and eventually cause failure of immunization. In this report, we identified immune escape variants in immunized babies born to hepatitis B surface antigen (HBsAg) carrier mothers. A total of 68 babies were followed up for 2 years after the full course of vaccination; 2.9% (2/68) of babies were found to be infected with the variant HBV in spite of preexisting antibody to surface antigen (anti-HBs) at 24 months post immunization. Both infants were positive for HBV-DNA; sequencing results of the "a" determinant region of the surface gene revealed that both babies had point mutations at a different nucleotide position resulting in various amino acid substitutions. In addition, an intriguing variant having an addition-deletion mutation was observed in one of the babies. This is the first report to show the addition-deletion variant of HBV in India. However, the immunological significance of the above HBV variants needs to be further elucidated. 相似文献
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Evaluation of Hybridization Capture Versus Amplicon‐Based Methods for Whole‐Exome Sequencing 下载免费PDF全文
Eric Samorodnitsky Benjamin M. Jewell Raffi Hagopian Jharna Miya Michele R. Wing Ezra Lyon Senthilkumar Damodaran Darshna Bhatt Julie W. Reeser Jharna Datta Sameek Roychowdhury 《Human mutation》2015,36(9):903-914
Next‐generation sequencing has aided characterization of genomic variation. While whole‐genome sequencing may capture all possible mutations, whole‐exome sequencing remains cost‐effective and captures most phenotype‐altering mutations. Initial strategies for exome enrichment utilized a hybridization‐based capture approach. Recently, amplicon‐based methods were designed to simplify preparation and utilize smaller DNA inputs. We evaluated two hybridization capture‐based and two amplicon‐based whole‐exome sequencing approaches, utilizing both Illumina and Ion Torrent sequencers, comparing on‐target alignment, uniformity, and variant calling. While the amplicon methods had higher on‐target rates, the hybridization capture‐based approaches demonstrated better uniformity. All methods identified many of the same single‐nucleotide variants, but each amplicon‐based method missed variants detected by the other three methods and reported additional variants discordant with all three other technologies. Many of these potential false positives or negatives appear to result from limited coverage, low variant frequency, vicinity to read starts/ends, or the need for platform‐specific variant calling algorithms. All methods demonstrated effective copy‐number variant calling when evaluated against a single‐nucleotide polymorphism array. This study illustrates some differences between whole‐exome sequencing approaches, highlights the need for selecting appropriate variant calling based on capture method, and will aid laboratories in selecting their preferred approach. 相似文献
18.
Rathinam Arunadevi Shanmugam Murugammal Dinesh Kumar Surendra Kumar Tandan 《Indian journal of pharmacology》2015,47(6):638-643
Objective:
The study is aimed to evaluate anti-inflammatory activity of Caesalpinia bonducella Fleming (Caesalpiniaceae) flower extract (CBFE) and to study its effect on radiographic outcome in adjuvant induced arthritis and authentication by high performance thin layer chromatography (HPTLC) chemical fingerprinting.Materials and Methods:
CBFE was administered orally (30, 100, and 300 mg/kg b.wt.) and tested for its anti-inflammatory activity in carrageenan-induced inflammation, cotton pellet induced chronic granulomatous inflammation and autacoids-induced inflammation. Effect on radiographic outcome was tested in adjuvant-induced arthritis. CBFE was HPTLC fingerprinted in suitable solvent system.Result:
In carrageenan-induced inflammation, CBFE produced significant inhibition in edema volume at all the doses (30, 100 and 300 mg/kg b.wt.) and percentage of inhibition was 28.68, 31.00, and 22.48, respectively as compared to control at 5 h of its administration. In cotton pellet granuloma assay, CBFE significantly decreased the granuloma weight at 300 mg/kg dose level by 22.53%. CBFE (300 mg/kg) caused significant inhibition by 37.5, 44.44, and 35.29% edema volume, at ½, 1 and 3 h after 5-hydroxytryptamine injection, respectively. Radiographic score of animals treated with 300 mg/kg CBFE was significantly decreased when compared to arthritic control animals.Conclusion:
The extract was found to possess significant anti-inflammatory activity. CBFE treatment improved the bony architecture in adjuvant-induced arthritis in rats. The developed HPTLC fingerprint would be helpful in the authentication of C. bonducella flower extract.KEY WORDS: 5-hydroxy tryptamine, Caesalpinia bonducella, carrageenan-induced inflammation, cotton pellet granuloma, high performance thin layer chromatography, radiography 相似文献19.
Frech Tracy M. VanBuren John M. Startup Emily Assassi Shervin Bernstein Elana J. Castelino Flavia V. Chung Lorinda Correia Chase Gordon Jessica K. Hant Faye N. Hummers Laura Khanna Dinesh Sandorfi Nora Shah Ami A. Shanmugam Victoria K. Steen Virginia Evnin Luke 《Clinical rheumatology》2021,40(3):965-971
Clinical Rheumatology - The objective of this analysis is to examine whether the severity of systemic sclerosis (SSc)-hand involvement influences patient-reported outcome measure (PROM) completion... 相似文献
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Rai Abhishek Senthilkumar Gandhipuram Periyasamy Mehalingam Vadivelan 《International journal of diabetes in developing countries.》2022,42(4):751-756
International Journal of Diabetes in Developing Countries - Urinary progranulin is an inflammatory marker that may indicate renal damage at an early stage of diabetic nephropathy. To determine... 相似文献