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Find video protocols related to scientific articles indexed in Pubmed.
Taxonomy of Aureobasidium spp. and biosynthesis and regulation of their extracellular polymers.
Crit. Rev. Microbiol.
PUBLISHED: 05-20-2015
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The genus Aureobasidium spp. have been divided into three species, A. pullulans. A. leucospermi and A. proteae, and A. pullulans has been known to have five varieties. However, after analysis of many strains of this yeast isolated from different environments, they do not belong to any of the three species or the five varieties. Although pullulan produced by A. pullulans has been widely used in different fields in industry and different strains of this yeast has been known to produce poly(?-L-malic acid) (PMA), heavy oils and ?-1,3-glucan, it is still unknown how the black yeast synthesizes and secretes the extracellular polymers at molecular level. In this review article, new biosynthetic pathways of pullulan, PMA and heavy oils, the enzymes and their genes related to their biosynthesis and regulation are proposed. Furthermore, some enzymes and their genes related to pullulan biosynthesis in A. pullulans have been characterized. But it is completely unknown how pullulan is secreted and how PMA, heavy oils and ?-1,3-glucan are synthesized and secreted. Therefore, there is much work to be done about taxonomy and biosynthesis, secretion and regulation of pullulan, PMA, heavy oils and ?-1,3-glucan at molecular levels in Aureobasidium spp.
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Myeloid-Derived Suppressor Cells Impair Alveolar Macrophages Through PD-1 Receptor Ligation During Pneumocystis Pneumonia.
Infect. Immun.
PUBLISHED: 11-19-2014
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Myeloid-derived suppressor cells (MDSCs) were recently found to accumulate in the lungs during Pneumocystis pneumonia (PcP). Adoptive transfer of these cells caused lung damage in recipient mice, suggesting that MDSC accumulation is a mechanism of pathogenesis in PcP. In this study, the phagocytic activity of alveolar macrophages (AMs) was found to decrease by 40% when they were incubated with MDSCs from Pneumocystis (Pc)-infected mice, compared to those incubated with Gr-1(+) cells from the bone marrow of uninfected mice. The expression of PU.1 gene in AMs incubated with MDSCs was also decreased. This PU.1 down regulation was mainly due to decreased histone 3 acetylation and increased DNA methylation caused by MDSCs. MDSCs were found to express high levels of PD-L1, and alveolar macrophages (AMs) were found to express high levels of PD-1 during PcP. Furthermore, PD-1 expression in AMs from uninfected mice was increased by 18 fold when they were incubated with MDSCs, compared to those incubated with Gr-1(+) cells from the bone marrow of uninfected mice. The adverse effects of MDSCs on AMs were diminished when the MDSCs were pretreated with anti-PD-L1 antibody, suggesting that MDSCs disable AMs through PD-1/PD-L1 ligation during PcP.
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Consecutive flap transfer for repairing massive soft tissue defects in the opisthenar with improved donor site closure.
Chin. J. Traumatol.
PUBLISHED: 10-09-2014
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To explore a surgical model of utilizing consecutive free scapular flap and adjacent pedicled flap transfer for repairing massive soft tissue defects on the dorsum of the hand while minimizing the donor site morbidity.
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Immune Responses of Piglets Immunized by a Recombinant Plasmid Containing Porcine Circovirus Type 2 and Porcine Interleukin-18 Genes.
Viral Immunol.
PUBLISHED: 10-01-2014
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Abstract In this study, two recombinant plasmids containing the ORF2 gene of porcine circovirus type 2 (PCV2) with or without porcine interleukin-18 (IL-18) were constructed and evaluated for their ability to protect piglets against PCV2 challenge. Transient expression of the plasmids in PK-15 cells could be detected using Western blot. Piglets were given two intramuscular immunizations 3 weeks apart and were challenged with a virulent Wuzhi strain of PCV2 at 42 days after the initial immunization. All animals vaccinated with pBudCE4.1-ORF2 or with pBudCE4.1-ORF2/IL18 developed PCV2-specific antibody and T-lymphocyte proliferative responses. The levels of T-lymphocyte proliferation in piglets immunized with pBudCE4.1-ORF2/IL18 were significantly higher than in those immunized with pBudCE4.1-ORF2, and pBudCE4.1-ORF2/IL18 stimulated a significantly increased production of IFN-? and IL-2. Furthermore, PCV2 challenge experiments showed that the DNA vaccine-immunized groups can partially prevent PCV2 viremia and significantly reduce the amount of PCV2 virus in the lymphoid tissues, and the piglets immunized by pBudCE4.1-ORF2/IL18 exhibit a marked inhibition of PCV2 replication compared to the pBudCE4.1-ORF2 group. These data demonstrate that the plasmid pBudCE4.1-ORF2/IL18 may be an effective approach for increasing PCV2 DNA vaccine immunogenicity.
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Bone formation in rabbit's leg muscle after autologous transplantation of bone marrow-derived mesenchymal stem cells expressing human bone morphogenic protein-2.
Indian J Orthop
PUBLISHED: 08-22-2014
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To test whether autologous transplantation of bone marrow-derived mesenchymal stem cells (BM-MSCs) expressing human bone morphogenic protein-2 (hBMP-2) can produce bone in rabbit leg muscles.
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Joint analysis of three genome-wide association studies of esophageal squamous cell carcinoma in Chinese populations.
Chen Wu, Zhaoming Wang, Xin Song, Xiao-Shan Feng, Christian C Abnet, Jie He, Nan Hu, Xian-Bo Zuo, Wen Tan, Qimin Zhan, Zhibin Hu, Zhonghu He, Weihua Jia, Yifeng Zhou, Kai Yu, Xiao-Ou Shu, Jian-Min Yuan, Wei Zheng, Xue-Ke Zhao, She-Gan Gao, Zhi-Qing Yuan, Fu-You Zhou, Zong-Min Fan, Ji-Li Cui, Hong-Li Lin, Xue-Na Han, Bei Li, Xi Chen, Sanford M Dawsey, Linda Liao, Maxwell P Lee, Ti Ding, You-Lin Qiao, Zhihua Liu, Yu Liu, Dianke Yu, Jiang Chang, Lixuan Wei, Yu-Tang Gao, Woon-Puay Koh, Yong-Bing Xiang, Ze-Zhong Tang, Jin-Hu Fan, Jing-jing Han, Sheng-Li Zhou, Peng Zhang, Dong-Yun Zhang, Yuan Yuan, Ying Huang, Chunling Liu, Kan Zhai, Yan Qiao, Guangfu Jin, Chuanhai Guo, Jianhua Fu, Xiaoping Miao, Changdong Lu, Haijun Yang, Chaoyu Wang, William A Wheeler, Mitchell Gail, Meredith Yeager, Jeff Yuenger, Er-Tao Guo, Ai-li Li, Wei Zhang, Xue-Min Li, Liang-Dan Sun, Bao-Gen Ma, Yan Li, Sa Tang, Xiu-Qing Peng, Jing Liu, Amy Hutchinson, Kevin Jacobs, Carol Giffen, Laurie Burdette, Joseph F Fraumeni, Hongbing Shen, Yang Ke, Yixin Zeng, Tangchun Wu, Peter Kraft, Charles C Chung, Margaret A Tucker, Zhi-Chao Hou, Ya-Li Liu, Yan-Long Hu, Li Wang, Guo Yuan, Li-Sha Chen, Xiao Liu, Teng Ma, Hui Meng, Li Sun, Xin-Min Li, Xiu-Min Li, Jian-Wei Ku, Ying-Fa Zhou, Liu-Qin Yang, Zhou Wang, Yin Li, Qirenwang Qige, Wen-jun Yang, Guang-Yan Lei, Long-qi Chen, En-Min Li, Ling Yuan, Wen-Bin Yue, Ran Wang, Lu-Wen Wang, Xue-Ping Fan, Fang-Heng Zhu, Wei-Xing Zhao, Yi-min Mao, Mei Zhang, Guo-Lan Xing, Ji-Lin Li, Min Han, Jing-Li Ren, Bin Liu, Shu-Wei Ren, Qing-Peng Kong, Feng Li, Ilyar Sheyhidin, Wu Wei, Yan-Rui Zhang, Chang-Wei Feng, Jin Wang, Yu-Hua Yang, Hong-Zhang Hao, Qi-De Bao, Bao-Chi Liu, Ai-Qun Wu, Dong Xie, Wan-Cai Yang, Liang Wang, Xiao-Hang Zhao, Shu-Qing Chen, Jun-Yan Hong, Xue-Jun Zhang, Neal D Freedman, Alisa M Goldstein, Dongxin Lin, Philip R Taylor, Li-dong Wang, Stephen J Chanock.
Nat. Genet.
PUBLISHED: 08-17-2014
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We conducted a joint (pooled) analysis of three genome-wide association studies (GWAS) of esophageal squamous cell carcinoma (ESCC) in individuals of Chinese ancestry (5,337 ESCC cases and 5,787 controls) with 9,654 ESCC cases and 10,058 controls for follow-up. In a logistic regression model adjusted for age, sex, study and two eigenvectors, two new loci achieved genome-wide significance, marked by rs7447927 at 5q31.2 (per-allele odds ratio (OR) = 0.85, 95% confidence interval (CI) = 0.82-0.88; P = 7.72 × 10(-20)) and rs1642764 at 17p13.1 (per-allele OR = 0.88, 95% CI = 0.85-0.91; P = 3.10 × 10(-13)). rs7447927 is a synonymous SNP in TMEM173, and rs1642764 is an intronic SNP in ATP1B2, near TP53. Furthermore, a locus in the HLA class II region at 6p21.32 (rs35597309) achieved genome-wide significance in the two populations at highest risk for ESSC (OR = 1.33, 95% CI = 1.22-1.46; P = 1.99 × 10(-10)). Our joint analysis identifies new ESCC susceptibility loci overall as well as a new locus unique to the population in the Taihang Mountain region at high risk of ESCC.
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[Caffeoyl phenylethanoid glycosides from Callicarpa kwangtungensis].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 08-07-2014
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Phytochemical investigation on the EtOH extract from the aerial part of Callicarpa kwangtungensis led to the isolation and characterization of 10 caffeoyl phenylethanoid glycosides, 2'-acetylacteoside (1), tubuloside E (2), acteoside (3), tubuloside B (4), isoacteoside (5), alyssonoside (6), 2'-acetylforsythoside B (7), brandioside (8), forsythoside B (9), and poliumoside (10). Compound 4 was isolated from the plants of Verbenaceae,and 6 was obtained from the Callicarpa genus, for the first time, while compounds 1, 2, 5 and 7 were firstly reported from the plant.
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Chloranthones A - D: minor and unprecedented dinor-eudesmenes from Chloranthus elatior.
Chem. Biodivers.
PUBLISHED: 06-18-2014
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Four novel naturally occurring diastereoisomers of dinor-eudesmenes, named chloranthones A-D (1-4, resp.), were isolated as minor components from the EtOH extract of the aerial parts of Chloranthus elatior. The unprecedented framework was established using extensive 2D-NMR techniques. Their absolute configurations were deduced from the observed Cotton effects in their circular dichroism (CD) spectra. A plausible biosynthetic pathway to the dinor-eudesmenes is proposed.
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Enhanced expression of the codon-optimized exo-inulinase gene from the yeast Meyerozyma guilliermondii in Saccharomyces sp. W0 and bioethanol production from inulin.
Appl. Microbiol. Biotechnol.
PUBLISHED: 06-02-2014
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In the present study, after the exo-inulinase gene INU1 from Meyerozyma guilliermondii was optimized according to the codon usage bias of Saccharomyces cerevisiae, both the optimized gene INU1Y and the native gene INU1 were ligated into the homologous integration expression vector pMIRSC11 and expressed in Saccharomyces sp. W0. It was determined that the inulinase activity of the recombinant yeast Y13 with the optimized gene INU1Y was 43.84 U/mL, which was obviously higher than that (31.39 U/mL) produced by the recombinant yeast EX3 with the native gene INU1. Moreover, it was indicated that the recombinant yeast Y13 could produce 126.30 mg/mL ethanol from 300.0 g/L inulin while the recombinant yeast EX3 and Saccharomyces sp. W0 produced 122.75 mg/mL and 114.15 mg/mL ethanol, respectively, under the same conditions. In addition, the ethanol productivity of the recombinant yeast Y13 was 2.25 mg/mL/h within 48 h of the fermentation, which was obviously higher than that of the recombinant yeast EX3 (1.97 mg/mL/h) and Saccharomyces sp. W0 (1.77 mg/mL/h) within the same period. The results demonstrated that the recombinant yeast Y13 had higher ethanol production and productivity than the recombinant yeast EX3 and Saccharomyces sp. W0. Therefore, it was concluded that the codon optimization of the exo-inulinase gene from M. guilliermondii effectively enhanced inulinase activity and improved ethanol production from inulin by Saccharomyces sp. W0 carrying the optimized inulinase gene.
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Role of integrins and their ligands in osteoarthritic cartilage.
Rheumatol. Int.
PUBLISHED: 05-25-2014
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Osteoarthritis (OA) is a degenerative disease, which is characterized by articular cartilage destruction, and mainly affects the older people. The extracellular matrix (ECM) provides a vital cellular environment, and interactions between the cell and ECM are important in regulating many biological processes, including cell growth, differentiation, and survival. However, the pathogenesis of this disease is not fully elucidated, and it cannot be cured totally. Integrins are one of the major receptors in chondrocytes. A number of studies confirmed that the chondrocytes express several integrins including ?5?1, ?V?3, ?V?5, ?6?1, ?1?1, ?2?1, ?10?1, and ?3?1, and some integrins ligands might act as the OA progression biomarkers. This review focuses on the functional role of integrins and their extracellular ligands in OA progression, especially OA cartilage. Clear understanding of the role of integrins and their ligands in OA cartilage may have impact on future development of successful therapeutic approaches to OA.
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Effect of osteopontin on TIMP-1 and TIMP-2 mRNA in chondrocytes of human knee osteoarthritis in vitro.
Exp Ther Med
PUBLISHED: 05-02-2014
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Tissue inhibitors of metalloproteinases (TIMPs) regulate the activity of matrix metalloproteinases (MMPs) and enzymes from the a disintegrin and metalloproteinase domain with thrombospondin motifs family in osteoarthritis (OA). Elevated osteopontin (OPN) levels in plasma, synovial fluid and articular cartilage are associated with progressive OA joint damage; however, the role of OPN in the pathological changes of knee OA remains undetermined. The present study was undertaken to examine the effect of OPN on the expression of TIMP-1 and TIMP-2 mRNA in chondrocytes from 16 patients with knee OA. In this study, following the stimulation of human chondrocytes with recombinant human OPN (rhOPN; 100 ng/ml and 1 ?g/ml, respectively) for 48 h, MTT assay was used to determine cell viability while the quantitative polymerase chain reaction (PCR) was used to detect the alterations in TIMP-1 and TIMP-2 levels. The results illustrated that neither 100 ng/ml nor 1 ?g/ml rhOPN caused cytotoxicity or apoptosis of chondrocytes and that the relative mRNA expression of TIMP-1 and TIMP-2 was significantly increased in the 1 ?g/ml rhOPN group compared with that in the control group (P=0.022 and P=0.003, respectively). However, no significant difference in expression was revealed between the 100 ng/ml rhOPN and control groups (P=0.998 and P=0.209, respectively). In conclusion, OPN may have a protective effect against pathological changes in advanced-stage OA.
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Regioselective synthesis of cytarabine monopropionate by using a fungal whole-cell biocatalyst in nonaqueous medium.
Bioorg. Med. Chem. Lett.
PUBLISHED: 03-27-2014
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The utilization of a dehydrated fungal biocatalyst of Aspergillus oryzae cells was successfully performed to achieve efficient acylation modification of a polar nucleoside cytarabine (ara-C). Organic solvents showed evident influence on the reaction catalyzed by the A. oryzae whole-cells. Except for hexane-pyridine, the catalytic activity and regioselectivity of the whole-cells clearly increased with increasing the polarity of the hydrophobic organic solvents used. The effects of some crucial factors on the reaction were further examined. The best reaction medium, hydrophobic solvent concentration, vinyl propionate/ara-C ratio, reaction temperature and shaking speed were confirmed as isopropyl ether (IPE)-pyridine, 30% (v/v), 90, 30 °C and 140-180 rpm, respectively. The cell biocatalyst also showed good thermal stabilities in both IPE-pyridine and hexane-pyridine systems. In addition, the desired 3'-O-propional derivative of ara-C was synthesized with the yields of 88.3% and regioselectivity (>70%). The resulting biocatalytic system appears to be an effective alternative, and can thus be employed for application in highly regioselective modification of nucleoside analogues.
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Sediment Type Affects Competition between a Native and an Exotic Species in Coastal China.
Sci Rep
PUBLISHED: 03-19-2014
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Different types of sediments in salt marsh have different physical and chemical characters. Thus sediment type plays a role in plant competition and growth in salt marsh ecosystems. Spartina anglica populations have been increasingly confined to upper elevation gradients of clay, and the niche sediment has changed. Because the niches of S. anglica and the native species Scirpus triqueter overlap, we conducted a greenhouse experiment to test the hypothesis that plant competition has changed under different types of sediments. Biomass and asexual reproduction were analyzed, and inter- and intraspecific competition was measured by log response ratio for the two species in both monoculture and combination under three sediment types (sand, clay and mixture of sand and clay). For S. anglica, biomass, ramet number and rhizome length in combination declined significantly compared with those in monoculture, and the intensity of interspecific competition was significantly higher than that of intraspecific competition under all sediments. For S. triqueter, the intensities of intra- and interspecific competition were not significantly different. This indicates that S. triqueter exerts an asymmetric competitive advantage over S. anglica across all sediments, but especially clay. Thus the sediment type changes competition between S. anglica and S. triqueter.
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Is posterior tibial slope associated with noncontact anterior cruciate ligament injury?
Knee Surg Sports Traumatol Arthrosc
PUBLISHED: 03-15-2014
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This study aimed to: (1) examine whether the association between posterior tibial slope and noncontact ACL injury exists in Chinese population; (2) compare the reliability and consistency of the three methods (longitudinal axis, posterior and anterior tibial cortex axis) in lateral radiograph.
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Heavy oils, principally long-chain n-alkanes secreted by Aureobasidium pullulans var. melanogenum strain P5 isolated from mangrove system.
J. Ind. Microbiol. Biotechnol.
PUBLISHED: 03-03-2014
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In this study, the yeast strain P5 isolated from a mangrove system was identified to be a strain of Aureobasidium pullulans var. melanogenum and was found to be able to secrete a large amount of heavy oil into medium. After optimization of the medium for heavy oil production and cell growth by the yeast strain P5, it was found that 120.0 g/l of glucose and 0.1 % corn steep liquor were the most suitable for heavy oil production. During 10-l fermentation, the yeast strain P5 produced 32.5 g/l of heavy oil and cell mass was 23.0 g/l within 168 h. The secreted heavy oils contained 66.15 % of the long-chain n-alkanes and 26.4 % of the fatty acids, whereas the compositions of the fatty acids in the yeast cells were only C16:0 (21.2 %), C16:1(2.8 %), C18:0 (2.9 %), C18:1 (39.8 %), and C18:2 (33.3 %). We think that the secreted heavy oils may be used as a new source of petroleum in marine environments. This is the first report of yeast cells which can secrete the long-chain n-alkanes.
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High-level pullulan production by Aureobasidium pullulans var. melanogenium P16 isolated from mangrove system.
Appl. Microbiol. Biotechnol.
PUBLISHED: 01-18-2014
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After over 100 strains of Aureobasidium spp. isolated from mangrove system were screened for their ability to produce exopolysaccharide (EPS), it was found that Aureobasidium pullulans var. melanogenium P16 strain among them could produce high level of EPS. Under the optimal conditions, 65.3 g/L EPS was produced by the P16 strain within 120 h at flask level. During 10-L batch fermentation, when the medium contained 120.0 g/L sucrose, 67.4 g/L of EPS and 23.1 g/L of cell dry weight in the culture were obtained within 120 h, leaving 0.78 g/L of reducing sugar and 11.4 g/L of total sugar in the fermented medium. It should be stressed that during the fermentation, no melanin was observed. After purification, the purified EPS was confirmed to be pullulan. This is the first time to report that A. pullulans var. melanogenium P16 strain isolated from the mangrove system can produce high level of pullulan.
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Development of an acellular tumor extracellular matrix as a three-dimensional scaffold for tumor engineering.
PLoS ONE
PUBLISHED: 01-01-2014
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Tumor engineering is defined as the construction of three-dimensional (3D) tumors in vitro with tissue engineering approaches. The present 3D scaffolds for tumor engineering have several limitations in terms of structure and function. To get an ideal 3D scaffold for tumor culture, A549 human pulmonary adenocarcinoma cells were implanted into immunodeficient mice to establish xenotransplatation models. Tumors were retrieved at 30-day implantation and sliced into sheets. They were subsequently decellularized by four procedures. Two decellularization methods, Tris-Trypsin-Triton multi-step treatment and sodium dodecyl sulfate (SDS) treatment, achieved complete cellular removal and thus were chosen for evaluation of histological and biochemical properties. Native tumor tissues were used as controls. Human breast cancer MCF-7 cells were cultured onto the two 3D scaffolds for further cell growth and growth factor secretion investigations, with the two-dimensional (2D) culture and cells cultured onto the Matrigel scaffolds used as controls. Results showed that Tris-Trypsin-Triton multi-step treated tumor sheets had well-preserved extracellular matrix structures and components. Their porosity was increased but elastic modulus was decreased compared with the native tumor samples. They supported MCF-7 cell repopulation and proliferation, as well as expression of growth factors. When cultured within the Tris-Trypsin-Triton treated scaffold, A549 cells and human colorectal adenocarcinoma cells (SW-480) had similar behaviors to MCF-7 cells, but human esophageal squamous cell carcinoma cells (KYSE-510) had a relatively slow cell repopulation rate. This study provides evidence that Tris-Trypsin-Triton treated acellular tumor extracellular matrices are promising 3D scaffolds with ideal spatial arrangement, biomechanical properties and biocompatibility for improved modeling of 3D tumor microenvironments.
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Fractal scaling of particle size distribution and relationships with topsoil properties affected by biological soil crusts.
PLoS ONE
PUBLISHED: 01-01-2014
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Biological soil crusts are common components of desert ecosystem; they cover ground surface and interact with topsoil that contribute to desertification control and degraded land restoration in arid and semiarid regions.
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[Segmental schwannomatosis in upper-extremity: 5 cases report and literature review].
Beijing Da Xue Xue Bao
PUBLISHED: 10-19-2013
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Multiple schwannomas localized in a single body part not crossing the midline constitute a rare variant of neurofibromatosis, segmental schwannomatosis. We report our experience with 5 cases of segmental schwannomatosis of the upper extremity and review the related literature to improve our skills in diagnosis and differentiation.
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[Central placement of screw fixation for scaphoid fracture: a biomechanical study].
Beijing Da Xue Xue Bao
PUBLISHED: 10-19-2013
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To evaluate the effect to the fixation stability of central screw placement during scaphoid fracture surgery.
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Effect of partial and complete posterior cruciate ligament transection on medial meniscus: A biomechanical evaluation in a cadaveric model.
Indian J Orthop
PUBLISHED: 10-18-2013
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The relationship between medial meniscus tear and posterior cruciate ligament (PCL) injury has not been exactly explained. We studied to investigate the biomechanical effect of partial and complete PCL transection on different parts of medial meniscus at different flexion angles under static loading conditions.
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Yeast killer toxins, molecular mechanisms of their action and their applications.
Crit. Rev. Biotechnol.
PUBLISHED: 10-10-2013
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Abstract Killer toxins secreted by some yeast strains are the proteins that kill sensitive cells of the same or related yeast genera. In recent years, many new yeast species have been found to be able to produce killer toxins against the pathogenic yeasts, especially Candida albicans. Some of the killer toxins have been purified and characterized, and the genes encoding the killer toxins have been cloned and characterized. Many new targets including different components of cell wall, plasma membrane, tRNA, DNA and others in the sensitive cells for the killer toxin action have been identified so that the new molecular mechanisms of action have been elucidated. However, it is still unknown how some of the newly discovered killer toxins kill the sensitive cells. Studies on the killer phenomenon in yeasts have provided valuable insights into a number of fundamental aspects of eukaryotic cell biology and interactions of different eukaryotic cells. Elucidation of the molecular mechanisms of their action will be helpful to develop the strategies to fight more and more harmful yeasts.
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Calcium malate overproduction by Penicillium viticola 152 using the medium containing corn steep liquor.
Appl. Microbiol. Biotechnol.
PUBLISHED: 09-29-2013
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In this study, after screening of eight fungal strains for their ability to produce calcium malate, it was found that Penicillium viticola 152 isolated from marine algae among them could produce the highest titer of calcium malate. At the same time, it was found that corn steep liquor (CSL) could stimulate calcium malate production and 0.5 % (v/v) CSL was the most suitable for calcium malate production. Under the optimal conditions, a titer of calcium malate in the supernatant was 132 g/l at flask level. During a 10-l fermentation, a titer of 168 g/l, a yield of 1.28 g/g of glucose, and a productivity of 1.75 g/l/h were reached within 96 h of the fermentation, and 93.4 % of the sugar was used for calcium malate production and cell growth, demonstrating that the titer, yield, and productivity of calcium malate by this fungal strain were very high and the fermentation period was very short. After analysis of the partially purified product with high-performance liquid chromatography, it was found that the main product was calcium malate. The results demonstrated that P. viticola 152 obtained in this study was the most suitable for developing a novel one-step fermentation process for calcium malate production from glucose on a large scale.
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The effect of mud therapy on pain relief in patients with knee osteoarthritis: a meta-analysis of randomized controlled trials.
J. Int. Med. Res.
PUBLISHED: 09-05-2013
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A meta-analysis was conducted to examine the effect of mud therapy on pain relief in patients with knee osteoarthritis (OA).
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Casuarinines A-J, lycodine-type alkaloids from Lycopodiastrum casuarinoides.
J. Nat. Prod.
PUBLISHED: 08-13-2013
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Ten new lycodine-type alkaloids, named casuarinines A-J (1-10), along with eight known analogues (11-18), were isolated from the whole plant of Lycopodiastrum casuarinoides . The new structures were established by spectroscopic methods and chemical transformations. Casuarinines A-D (1-4) and J (10) are common lycodine alkaloids possessing four connected six-membered rings, while tricyclic casuarinines E-H (5-8) are the piperidine ring cleavage products. In particular, casuarinine I (9) has an unprecedented five-membered tetrahydropyrrole ring instead of the piperidine ring. A plausible biosynthetic pathway to 9 is proposed. Among the compounds reported, casuarinine H (8) exhibited significant neuroprotective effect against hydrogen peroxide (H?O?)-induced neuronal cell damage in human neuroblastoma SH-SY5Y cells, while casuarinines C (3) and I (9) showed moderate inhibitory activity against acetylcholinesterase (AChE).
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Congenital symbrachydactyly: outcomes of surgical treatment in 120 webs.
Chin. Med. J.
PUBLISHED: 08-09-2013
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Symbrachydactyly is defined as a combination of short fingers with syndactyly. There are few published reports estimating the incidence of symbrachydactyly. The aim of this study was to investigate the clinical features and the outcome of surgical treatment for congenital symbrachydactyly.
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Schwannomatosis: a new member of neurofibromatosis family.
Chin. Med. J.
PUBLISHED: 07-24-2013
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Schwannomatosis is a recently recognized peripheral nerve polyneoplasm with clinical characteristics and a genetic background that differ from those of neurofibromatosis 2 (NF2). The diagnostic and treatment criteria of this rare disorder are herein discussed.
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Ethanol production from inulin and unsterilized meal of Jerusalem artichoke tubers by Saccharomyces sp. W0 expressing the endo-inulinase gene from Arthrobacter sp.
Bioresour. Technol.
PUBLISHED: 06-29-2013
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After the endo-inulinase gene from Arthrobacter sp. was ligated the expression vectors pMIDSC31 and pMIRSC31, the endo-inulinase gene was inserted into the chromosomal DNA of Saccharomyces sp. W0. It was found that the inulinase activity of the recombinant yeast D5 in which the endo-inulinase gene was inserted into the delta sequence was higher than that of the recombinant yeast R1 in which the endo-inulinase gene was inserted into 18S rDNA sequence. More ethanol from inulin was produced by the recombinant yeast D5 than by the recombinant yeast R1. But Saccharomyces sp. W0 produced the lowest inulinase activity and concentration of ethanol. During the 3-l fermentation, the recombinant yeast D5 could produce 13.6 ml of ethanol per 100ml of the fermented medium from 30% inulin. The recombinant yeast D5 could actively convert the unsterilized meal of Jerusalem artichoke tubers, yielding 10.1 ml of ethanol per 100ml of the fermented medium.
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Overproduction of poly(?-malic acid) (PMA) from glucose by a novel Aureobasidium sp. P6 strain isolated from mangrove system.
Appl. Microbiol. Biotechnol.
PUBLISHED: 06-25-2013
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After over 100 strains of Aureobasidium spp isolated from mangrove system were screened for their ability to produce poly(?-malic acid) (PMA), it was found that Aureobasidium sp. P6 strain among them could produce high level of Ca(2+)-PMA. Fourteen percent glucose and 6.5 % CaCO3 in the medium were the most suitable for Ca(2+)-PMA production. Then, 100.7 g/l of Ca(2+)-PMA was produced using Aureobasidium sp. P6 strain within 168 h at flask level. During 10-l batch fermentation, when the medium contained 12.0 % glucose, 98.7 g/l of Ca(2+)-PMA in the culture and 14.7 g/l of cell dry weight were obtained within 156 h, leaving 0.34 % reducing sugar in the fermented medium. When glucose concentration in the fermentation medium was 14.0 %, 118.3 g/l of Ca(2+)-PMA in the culture and 16.4 g/l of cell dry weight were obtained within 168 h, leaving 0.4 % reducing sugar in the fermented medium. After purification of Ca(2+)-PMA from the culture and acid hydrolysis of the pure Ca(2+)-PMA, analysis of HPLC showed that Aureobasidium sp. P6 strain only produced two main components of Ca(2+)-PMA and minor amount of calcium malate and that the hydrolysate of PMA was mainly composed of calcium malate. This is the first time to report that the novel yeast strain Aureobasidium sp. P6 strain isolated from the mangrove systems can produce such high amount of Ca(2+)-PMA.
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Establishing a central zone in scaphoid surgery: a computational approach.
Int Orthop
PUBLISHED: 06-03-2013
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Scaphoid fractures are commonly fixed with headless cannulated screws positioned centrally in the scaphoid. Judgement of central placement of the screw may be difficult. We generated a central zone using computer analysis of 3D reconstructions of computed tomography (CT) images. As long as the screw axis is completely contained within this central zone, the screw would be considered as centrally placed.
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Intrinsic fiber-optic Fabry-Perot interferometer based on arc discharge and single-mode fiber.
Appl Opt
PUBLISHED: 05-15-2013
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We propose a simple intrinsic Fabry-Perot interferometer (FPI) based on single-mode fiber, where a thin film is formed by arc discharge to serve as one mirror of the FPI cavity. The temperature and refractive-index (RI) characteristics of the proposed device are investigated. Experimental results show that the device can provide temperature-independent measurement of RI with a fringe-contrast sensitivity of ~72.59 dB/RIU (RI units). Meanwhile, it can also be used as a temperature sensor with a wavelength sensitivity of ~8 pm/°C. Therefore, the potential simultaneous measurement of RI and temperature could be realized by detecting the variations of fringe contrast and wavelength, respectively.
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Single-dose intra-articular morphine after arthroscopic knee surgery: a meta-analysis of randomized placebo-controlled studies.
Arthroscopy
PUBLISHED: 04-05-2013
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The purpose of this quantitative meta-analysis is to appraise the efficacy and side effects of intra-articular morphine in patients undergoing arthroscopic knee surgery.
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Immobilization of pectinase on oxidized pulp fiber and its application in whitewater treatment.
Carbohydr Polym
PUBLISHED: 03-04-2013
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Modified pulp fiber was originally used as a new type of carrier for pectinase immobilization. Pulp fiber was oxidized by sodium periodate to produce aldehyde groups for covalently binding with amino groups of pectinase. Results showed that the enzymatic activity of immobilized pectinase on pulp fiber reached 65 ?gg(-1)min(-1) when immobilization pH value, temperature and time were of 7.0, 20 °C and 15 min, respectively. The immobilized pectinase showed higher thermo stability in a wider temperature range of 40-70 °C than its free type and its optimal pH shifted from 8.0 to 8.8. Furthermore, the immobilized pectinase exhibited good operational stability. When employed in whitewater treatment of papermaking industry, it still efficiently decreased the cationic demand after operating repeatedly for six batches. The results obtained demonstrate a promising route to prepare available, cheap and biodegradable carrier for immobilizing enzymes with potential application in wastewater treatment in papermaking industry.
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Quantum chaotic scattering in graphene systems in the absence of invariant classical dynamics.
Phys Rev E Stat Nonlin Soft Matter Phys
PUBLISHED: 01-14-2013
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Quantum chaotic scattering is referred to as the study of quantum behaviors of open Hamiltonian systems that exhibit transient chaos in the classical limit. Traditionally a central issue in this field is how the elements of the scattering matrix or their functions fluctuate as a system parameter, e.g., the electron Fermi energy, is changed. A tacit hypothesis underlying previous works was that the underlying classical phase-space structure remains invariant as the parameter varies, so semiclassical theory can be used to explain various phenomena in quantum chaotic scattering. There are, however, experimental situations where the corresponding classical chaotic dynamics can change characteristically with some physical parameter. Multiple-terminal quantum dots are one such example where, when a magnetic field is present, the classical chaotic-scattering dynamics can change between being nonhyperbolic and being hyperbolic as the Fermi energy is changed continuously. For such systems semiclassical theory is inadequate to account for the characteristics of conductance fluctuations with the Fermi energy. To develop a general framework for quantum chaotic scattering associated with variable classical dynamics, we use multi-terminal graphene quantum-dot systems as a prototypical model. We find that significant conductance fluctuations occur with the Fermi energy even for fixed magnetic field strength, and the characteristics of the fluctuation patterns depend on the energy. We propose and validate that the statistical behaviors of the conductance-fluctuation patterns can be understood by the complex eigenvalue spectrum of the generalized, complex Hamiltonian of the system which includes self-energies resulted from the interactions between the device and the semi-infinite leads. As the Fermi energy is increased, complex eigenvalues with extremely smaller imaginary parts emerge, leading to sharp resonances in the conductance.
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All-trans retinoic acid in combination with primaquine clears pneumocystis infection.
PLoS ONE
PUBLISHED: 01-04-2013
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Pneumocystis pneumonia (PcP) develops in immunocompromised patients. Alveolar macrophages play a key role in the recognition, phagocytosis, and degradation of Pneumocystis, but their number is decreased in PcP. Our study of various inflammatory components during PcP found that myeloid-derived suppressor cells (MDSCs) accumulate in the lungs of mice and rats with Pneumocystis pneumonia (PcP). We hypothesized that treatment with all-trans retinoic acid (ATRA), a metabolite of vitamin A, may effectively control Pneumocystis (Pc) infection by inducing MDSCs to differentiate to AMs. In rodent models of PcP, we found that 5 weeks of ATRA treatment reduced the number of MDSCs in the lungs and increased the number of AMs which cleared Pc infection. We also found that ATRA in combination with primaquine was as effective as the combination of trimethoprim and sulfamethaxazole for treatment of PcP and completely eliminated MDSCs and Pc organisms in the lungs in two weeks. No relapse of PcP was seen after three weeks of the ATRA-primaquine combination treatment. Prolonged survival of Pc-infected animals was also achieved by this regimen. This is the very first successful development of a therapeutic regimen for PcP that combines an immune modulator with an antibiotic, enabling the hosts to effectively defend the infection. Results of our study may serve as a model for development of novel therapies for other infections with MDSC accumulation.
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Expression of CD44 in articular cartilage is associated with disease severity in knee osteoarthritis.
Mod Rheumatol
PUBLISHED: 01-03-2013
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To investigate CD44 levels in articular cartilage of knee osteoarthritis (OA) and the relationship between CD44 and severity of the disease.
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Effects of soil nutrient heterogeneity on intraspecific competition in the invasive, clonal plant Alternanthera philoxeroides.
Ann. Bot.
PUBLISHED: 12-29-2011
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Fine-scale, spatial heterogeneity in soil nutrient availability can increase the growth of individual plants, the productivity of plant communities and interspecific competition. If this is due to the ability of plants to concentrate their roots where nutrient levels are high, then nutrient heterogeneity should have little effect on intraspecific competition, especially when there are no genotypic differences between individuals in root plasticity. We tested this hypothesis in a widespread, clonal species in which individual plants are known to respond to nutrient heterogeneity.
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Effect of posterior cruciate ligament rupture on biomechanical features of the medial femoral condyle.
Orthop Surg
PUBLISHED: 10-20-2011
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To investigate the biomechanical impact of rupture of the posterior cruciate ligament (PCL) and its various bundles on the medial femoral condyle.
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[Establishment of a "central zone" in the scaphoid bone by computer analysis of three-dimensional reconstructions of computed tomography imaging and selection of central location of the scaphoid screw].
Beijing Da Xue Xue Bao
PUBLISHED: 10-20-2011
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To establish an area by generating a surface model located a certain distance inside the scaphoid bone by computer analysis of three-dimensional reconstructions of computed tomography images, and define the central zone of the scaphoid.
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[An epidemiological investigation of acute occupational hand injuries].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 10-07-2011
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To study composition, distribution and causes of acute occupational hand injuries in Beijing Jishuitan Hospital.
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Serine racemase rs391300 G/A polymorphism influences the therapeutic efficacy of metformin in Chinese patients with diabetes mellitus type 2.
Clin. Exp. Pharmacol. Physiol.
PUBLISHED: 09-22-2011
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1. The aim of this study was to investigate the association of the serine racemase (SRR) rs391300 G/A polymorphism with the risk of diabetes mellitus type 2 (T2DM) and to assess the impacts of the polymorphism on the therapeutic efficacy of metformin in Chinese patients. 2. A case-control study of 402 patients with T2DM and 171 healthy controls was conducted. The SRR rs391300 polymorphism was genotyped in all participants using the ABI 3700 automated sequencer. Forty-four recent-onset T2DM patients with different rs391300 genotypes were selected to receive 500 mg metformin orally daily for 12 consecutive weeks as monotherapy. Serum fasting plasma glucose (FPG), postprandial plasma glucose (PPG), glycated haemoglobin (HbA1c), fasting serum insulin (FINS), postprandial serum insulin (PINS), triglycerol (TG), cholesterol (CHO), low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), homeostasis model assessment for insulin resistance (HOMA-IR), and body mass index (BMI) were determined before and after metformin treatment. 3. The distribution frequencies of rs391300 were in agreement with Hardy-Weinberg equilibrium (P > 0.05). After treatment with metformin, the values of BMI, FPG, PPG, PINS, HbA1c, CHO, and TG decreased significantly (P < 0.01), whereas FINS increased (P < 0.001), in patients with T2DM. Patients with the GA or AA genotype of rs391300 showed better improvements in the levels of FPG, PPG, and CHO (P < 0.05) than individuals with the GG genotype. 4. The SRR rs391300 polymorphism was associated with the therapeutic efficacy of metformin in Chinese patients with T2DM.
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Biomechanical comparison of lumbar total disc arthroplasty, discectomy, and fusion: effect on adjacent-level disc pressure and facet joint force.
J Neurosurg Spine
PUBLISHED: 07-22-2011
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With the increasing advocacy for total disc replacement (TDR) as a potential alternative to fusion in the management of lumbar degenerative disc disease, intradiscal pressures (IDPs) and facet joint stresses at the adjacent levels of spine have generated considerable interest. The purpose of this study was to compare adjacent-level IDPs and facet joint stresses among TDR, discectomy, and fusion.
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Biomechanical evaluation of tenodesis reconstruction in ankle with deltoid ligament deficiency: a finite element analysis.
Knee Surg Sports Traumatol Arthrosc
PUBLISHED: 07-01-2011
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Isolated deltoid ligament injuries are relatively uncommon but can be a significant source of pain and disability. Several approaches to deltoid reconstruction have been reported. However, there is no previous comparative study of Wiltberger, Deland, Kitaoka and Hintermann procedures with respect to biomechanical characteristics such as kinematics, ligaments and grafts stresses using finite element analysis. The purpose of this study was to evaluate the biomechanical results of those deltoid ligament reconstructions using finite element analysis.
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Bone turnover in passive smoking female rat: relationships to change in bone mineral density.
BMC Musculoskelet Disord
PUBLISHED: 06-11-2011
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Many studies have identified smoking as a risk factor for osteoporosis, but it is unclear whether passive smoking has an effect on bone mineral density and bone turnover and if such an effect could cause osteoporosis.The purpose of the study was to investigate the effect of passive smoking on bone mineral density (BMD) and bone turnover and the relationship between BMD and bone turnover in female rat.
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Effects of the crude extract of Polygala tenuifolia Willd on human sperm in vitro.
J Zhejiang Univ Sci B
PUBLISHED: 06-03-2011
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The aim of the present study is to analyze sperm membrane changes and the spermicidal effect in treatment with the crude extract from Polygala tenuifolia Willd (PTW) in vitro. The root of PTW was extracted in distilled water. Normal human spermatozoa were used to assess the spermicidal activity (Sander-Cramer assay) of the extract from the PTW root. The hypo-osmotic swelling (HOS) test and the eosin Y (EY) staining were used to detect the integrity of sperm membrane and vitality. The sperm chromatin dispersion (SCD) test was performed to determine sperm DNA integrity. N-9 was used as a reference standard and semen added to physiological saline was used as the control. Semen samples were donated by 42 healthy fertile men. The crude extract from the root of PTW could immobilize and kill 100% spermatozoa within 20 s in vitro at the concentrations of 20.0 and 10.0 mg/ml; at the concentration of 5.0 mg/ml, spermatozoa were immobilized in (39.5±3.2) s. In the groups of the crude extract from the root of PTW and N-9 solution, the rate of the normal HOS (tails swollen) and the white head (unstained) was 0%, and the rate of the abnormal HOS (tails unswollen) and red head (stained) was 100%. Sperm DNA fragmentation showed no change in exposure to the crude extract from the root of PTW and N-9 solution. The sperm revival test did not show any spermatozoa that recovered their motilities. The rapid spermicidal activity of the crude extract from the root of PTW in vitro may occur by the disruption of the sperm membrane integrity.
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NAMPT -3186C/T polymorphism affects repaglinide response in Chinese patients with Type 2 diabetes mellitus.
Clin. Exp. Pharmacol. Physiol.
PUBLISHED: 06-03-2011
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1. In the present study, we investigated the associations of nicotinamide phosphoribosyltransferase (NAMPT)-3186 C/T and -948G/T polymorphisms with the risk of Type 2 diabetes mellitus (T2DM) and their impact on the efficacy of repaglinide in Chinese Han T2DM patients. 2. In all, 170 patients with T2DM and 129 healthy controls were genotyped for NAMPT-948G>T and -3186C>T polymorphisms. Thirty-five patients with different NAMPT -3186 C/T genotypes and the same organic anion-transporting polypeptide 1B1 (OATP1B1521) T/C genotype were randomly selected to undergo 8 weeks preprandial repaglinide treatment (1 mg, three times daily). Serum fasting plasma glucose (FPG), post-prandial plasma glucose (PPG), glycated haemoglobin (HbAlc), fasting serum insulin (FINS), post-prandial serum insulin (PINS), triglyceride (TG), total cholesterol (CHO), homeostasis model assessment of insulin resistance (HOMA-IR), low-density lipoprotein-cholesterol (LDL-C) and high-density lipoprotein-cholesterol (HDL-C) were determined before and after repaglinide treatment. 3. After repaglinide treatment for 8 consecutive weeks, there were significantly decreases in PFG, PPG, HbAlc, CHO and LDL-C, and increases in FINS, HDL-C and the HDL-C : LDL-C ratio, in T2DM patients. The elevated PINS value in patients with CT genotypes was significantly lower than that in patients with the CC and TT genotypes (P < 0.05) and there were significant differences in CHO between patients with the CT genotype and the CC or TT genotype (P < 0.05). 4. The data suggest that the NAMPT -3186C>T polymorphism is significantly associated with plasma levels of PINS and CHO in Chinese T2DM patients with repaglinide monotherapy.
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Burial depth and stolon internode length independently affect survival of small clonal fragments.
PLoS ONE
PUBLISHED: 04-19-2011
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Disturbance can fragment plant clones into different sizes and unstabilize soils to different degrees, so that clonal fragments of different sizes can be buried in soils at different depths. As a short-term storage organ, solon internode may help fragmented clones of stoloniferous plants to withstand deeper burial in soils. We address (1) whether burial in soils decreases survival and growth of small clonal fragments, and (2) whether increasing internode length increases survival and growth of small fragments under burial. We conducted an experiment with the stoloniferous, invasive herb Alternanthera philoxeroides, in which single-node fragments with stolon internode of 0, 2, 4 and 8 cm were buried in soils at 0, 2, 4 and 8 cm depth, respectively. Increasing burial depth significantly reduced survival of the A. philoxeroides plants and increased root to shoot ratio and total stolon length, but did not change growth measures. Increasing internode length significantly increased survival and growth measures, but there was no interaction effect with burial depth on any traits measured. These results indicate that reserves stored in stolon internodes can contribute to the fitness of the A. philoxeroides plants subject to disturbance. Although burial reduced the regeneration capacity of the A. philoxeroides plants, the species may maintain the fitness by changing biomass allocation and stolon length once it survived the burial. Such responses may play an important role for A. philoxeroides in establishment and invasiveness in frequently disturbed habitats.
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A novel biocatalytic approach to acetylation of 1-?-D-arabinofuranosylcytosine by Aspergillus oryzae whole cell in organic solvents.
Appl. Microbiol. Biotechnol.
PUBLISHED: 04-07-2011
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Biocatalytic acylation of 1-?-D-arabinofuranosylcytosine (ara-C) was developed using whole cell of Aspergillus oryzae as a novel catalyst. (13)C nuclear magnetic resonance (NMR) analysis indicated that the whole-cell biocatalyst had more specific activity toward the 3-hydroxyl group than 5-hydroxyl group among the available hydroxyl groups in sugar moiety of ara-C. Except for glucose and maltose, 11 carbon sources supplemented to basal media, including Spans, Tweens, olive oil and oleic acid, exhibited notable enhancement effects on both the cell growth and the acylation reactions. It was suggested that the carbon sources containing controlled-release oleic acid were the important substrates for the production of fungal cell-bound lipase with specific activity, partially due to a gradual induction effect of their released oleic acid on the cell-bound lipase production. Despite the low initial reaction rate and substrate conversion, the addition of 2.0 g/l Span 80 resulted in a higher 3-regioselectivity of the cells than 81%. By using Tween 85 at its optimum concentration of 5.0 g/l, however, the highest initial rates (3.2 mmol/l h) and substrate conversion (76%) of the whole-cell catalyzed acylation of ara-C can be achieved. It was also found that the 3-regioselectivity of the cells showed observable increase by extending the culture time. And the activity of cell-bound lipase drastically increased in the early stage of cell growth and then declined in the late culture stage, whatever the culture media used. Our results thus indicated that A. oryzae whole cell was a promising green tool for biosynthesis of nucleoside esters with potential bioactivities.
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[Fast segmentation algorithm of high resolution remote sensing image based on multiscale mean shift].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 03-25-2011
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Mean Shift algorithm is a robust approach toward feature space analysis and it has been used wildly for natural scene image and medical image segmentation. However, high computational complexity of the algorithm has constrained its application in remote sensing images with massive information. A fast image segmentation algorithm is presented by extending traditional mean shift method to wavelet domain. In order to evaluate the effectiveness of the proposed algorithm, multispectral remote sensing image and synthetic image are utilized. The results show that the proposed algorithm can improve the speed 5-7 times compared to the traditional MS method in the premise of segmentation quality assurance.
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Causative organisms and their antibiotic resistance patterns for childhood septic arthritis in china between 1989 and 2008.
Orthopedics
PUBLISHED: 03-18-2011
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The goal of this study was to evaluate the array of causative organisms for septic arthritis in children and their antibiotic resistance patterns over a 20-year period at a single medical center. The medical records of children younger than 16 years with septic arthritis admitted to a hospital in China from 1989 to 2008 were retrospectively reviewed. A total of 158 cases of septic arthritis were studied, 70 from 1989 to 1998 and 88 from 1999 to 2008. Between the first and second decades, occurrence of serious illnesses decreased significantly from 44.3% to 28.4% (P<.04). The positive percentage was only 55.6% in the first decade and 44.82% in the second decade. The causative organisms of major significance between the 2 decades changed little, except methicillin-resistant Staphylococcus aureus (MRSA) increasing significantly. Staphylococci remained the major causative organisms for joint infection. The percentage of Staphylococcus aureus resistance to various antibiotics increased: 85% to 100% for penicillin, 58.8% to 75% for erythromycin, 0% to 31.3% for cefazolin, and 15% to 29.4% for multi-resistance. In the second decade, 4 MRSA stains were multi-resistant. However, gentamincin resistance remained at the same level. Antibiotic resistance of coagulase-negative staphylococci and gram-negative bacilli changed little. The incidences of osteomyelitis and joint dislocation decreased significantly, from 15.7% to 6% and 28.6% to 14.8%, respectively (P<.04). The distribution of causative organisms of septic arthritis in young patients changed slightly during the 20-year period, while antibiotic resistance of the major causative organisms increased and the incidences of serious illness-osteomyelitis and joint dislocation-decreased significantly.
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Reversible contraceptive effect of the oviduct plug with nickel-titanium shape memory alloy and silicone rubber in rabbits.
Contraception
PUBLISHED: 03-15-2011
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The aim of this study was to observe the contraceptive effectiveness and reversibility of the oviduct plug with nickel-titanium (Ni-Ti) shape memory alloy and silicone rubber in rabbits.
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Nitrogen level changes the interactions between a native (Scirpus triqueter) and an exotic species (Spartina anglica) in Coastal China.
PLoS ONE
PUBLISHED: 02-25-2011
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The exotic species Spartina anglica, introduced from Europe in 1963, has been experiencing a decline in the past decade in coastal China, but the reasons for the decline are still not clear. It is hypothesized that competition with the native species Scirpus triqueter may have played an important role in the decline due to niche overlap in the field. We measured biomass, leaf number and area, asexual reproduction and relative neighborhood effect (RNE) of the two species in both monoculture and mixture under three nitrogen levels (control, low and high). S. anglica showed significantly lower biomass accumulation, leaf number and asexual reproduction in mixture than in monoculture. The inter- and intra-specific RNE of S. anglica were all positive, and the inter-specific RNE was significantly higher than the intra-specific RNE in the control. For S. triqueter, inter- and intra-specific RNE were negative at the high nitrogen level but positive in the control and at the low nitrogen level. This indicates that S. triqueter exerted an asymmetric competitive advantage over S. anglica in the control and low nitrogen conditions; however, S. anglica facilitated growth of S. triqueter in high nitrogen conditions. Nitrogen level changed the interactions between the two species because S. triqueter better tolerated low nitrogen. Since S. anglica is increasingly confined to upper, more nitrogen-limited marsh areas in coastal China, increased competition from S. triqueter may help explain its decline.
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Nutrients removal and recovery from anaerobically digested swine wastewater by struvite crystallization without chemical additions.
J. Hazard. Mater.
PUBLISHED: 02-19-2011
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Anaerobically digested swine wastewater contains high concentrations of phosphorus (P) and nitrogen (N). A pilot-scale experiment was carried out for nutrients removal and recovery from anaerobically digested swine wastewater by struvite crystallization. In the pilot plant, a sequencing batch reactor (SBR) and a continuous-flow reactor with struvite accumulation devices were designed and employed. The wastewater pH value was increased by CO(2) stripping, and the struvite crystallization process was performed without alkali and Mg(2+) additions. Results of the long-term operation of the system showed that, both reactors provided up to 85% P removal and recovery over wide ranges of aeration times (1.0-4.0 h), hydraulic retention times (HRT) (6.0-15.0 h) and temperatures (0-29.5°C) for an extended period of 247 d, in which approximate 30% of P was recovered by the struvite accumulation devices. However, 40-90% of NH(4)(+)-N removed was through air stripping instead of being immobilized in the recovered solids. The recovered products were detected and analyzed by scanning electron microscope (SEM), X-ray diffraction (XRD) and chemical methods, which were proved to be struvite with purity of more than 90%. This work demonstrated the feasibility and effects of nutrients removal and recovery from anaerobically digested swine wastewater by struvite crystallization without chemical additions.
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Delineation of the translocation of colicin E7 across the inner membrane of Escherichia coli.
Arch. Microbiol.
PUBLISHED: 02-17-2011
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The lysis protein of the colicinogenic operon is essential for colicin release and its main function is to activate the outer membrane phospholipase A (OMPLA) for the traverse of colicin across the cell envelope. However, little is known about the involvement of the lysis protein in the translocation of colicin across the inner membrane into the periplasm. The introduction of specific point mutations into the lipobox or sorting signal sequence of the lysE7 gene resulted in the production of various forms of lysis proteins. Our experimental results indicated that cells with wild-type mature LysE7 protein exhibited higher efficiency of colicin E7 translocation across the inner membrane into the periplasm than those with premature LysE7 protein. Moreover, the degree of permeability of the inner membrane induced by the mature LysE7 protein was significantly increased as compared to the unmodified LysE7 precursor. These results suggest that the efficiency of colicin movement into the periplasm is correlated with the increase in inner membrane permeability induced by the LysE7 protein. Thus, we propose that mature LysE7 protein has two critical roles: firstly mediating the translocation of colicin E7 across the inner membrane into the periplasm, and secondly activating the OMPLA to allow colicin release.
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Repression of btuB gene transcription in Escherichia coli by the GadX protein.
BMC Microbiol.
PUBLISHED: 02-11-2011
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BtuB (B twelve uptake) is an outer membrane protein of Escherichia coli. It serves as a receptor for cobalamines uptake or bactericidal toxin entry. A decrease in the production of the BtuB protein would cause E. coli to become resistant to colicins. The production of BtuB has been shown to be regulated at the post-transcriptional level. The secondary structure of 5 untranslated region of btuB mRNA and the intracellular concentration of adenosylcobalamin (Ado-Cbl) would affect the translational efficiency and RNA stability of btuB gene. The transcriptional regulation of btuB expression is still unclear.
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Mig1 is involved in mycelial formation and expression of the genes encoding extracellular enzymes in Saccharomycopsis fibuligera A11.
Fungal Genet. Biol.
PUBLISHED: 02-08-2011
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The MIG1 gene of Saccharomycopsis fibuligera A11 was cloned from its genomic DNA using the degenerated primers and inverse PCR. The MIG1 gene (1152bp, accession number: HM450676) encoded a 384-amino acid protein very similar to Mig1s from other fungi. Besides their highly conserved zinc fingers, the Mig1 proteins displayed short conserved motifs of possible significance in glucose repression. The MIG1 gene in S. fibuligera A11 was disrupted by integrating the HPT (hygromycin B phosphotransferase) gene into ORF (Open Reading Frame) of the MIG1 gene. The disruptant A11-c obtained could grow in the media containing hygromycin and 2-deoxy-d-glucose, respectively. ?-Amylase, glucoamylse, acid protease and ?-glucosidase production by the disruptant and expression of their genes in the disruptant were greatly enhanced. This confirms that Mig1, the transcriptional repressor, indeed regulates expression of the genes and production of the extracellular enzymes in S. fibuligera A11. At the same time, it was found that cell budding was enhanced and mycelial formation was reduced in the disruptant.
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[Effects of high concentration ozone on soybean growth and grain yield].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 12-01-2010
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By using open top chambers (OTCs), soybean plants were grown in pots, and exposed to charcoal-filtered air ([O3] < 10 microg x kg(-1)) and elevated O3 (80 microg x kg(-1)) after anthesis, aimed to investigate the responses of soybean s agronomic characters, leaf area, chlorophyll content, antioxidant system, and grain yield to elevated O3. Under elevated O3, the leaf area and chlorophyll content decreased significantly (P < 0.05), and the leaf catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) activities had a significant increase (P < 0.01) first but a gradual decrease then, compared with those under charcoal-filtered air. Elevated O3 decreased the leaf soluble protein and ascorbate content (AsA) contents while increased the leaf malonaldehyde (MDA) content (P < 0.05), suggesting that the leaf membrane lipid peroxidation was accelerated. The dry mass per plant, effective pod number, grain number, 100-grains weight, and grain yield under elevated O3 had somewhat decreased, among which, grain yield decreased significantly, with the decrement reached to 47% (P < 0.01).
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[A method of measuring the displacement of the distal radioulnar joint on the three-dimensional CT imaging].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 11-09-2010
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To establish a clinical method for measuring the displacement of the distal radioulnar joint (DRUJ) precisely irrespective of ulnar variance, and to derive normal population translation references with palmar and dorsal stress.
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Sevoflurane postconditioning ameliorates oxygen-glucose deprivation-reperfusion injury in the rat hippocampus.
CNS Neurosci Ther
PUBLISHED: 09-28-2010
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Sevoflurane is well known to exert a neuroprotective effect through anesthetic preconditioning. However, its effects on postconditioning, a neuroprotective phenomenon following an insult, have not been well studied.
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Interaction of colicin E7 with the major coat protein (g8p) may confer limited protection on colicinogenic Escherichia coli against M13 bacteriophage infection.
Microbiology (Reading, Engl.)
PUBLISHED: 08-05-2010
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Colicin release provides producer strains with a competitive advantage under certain circumstances. We found that propagation of M13 bacteriophage in cells producing colicin E7 is impaired, without alteration in the efficiency of bacteriophage adsorption, as compared with non-producing cells. In contrast to the protective effect of the colicin against M13 bacteriophage infection, the endogenously expressed colicin does not confer limited protection against transfection with M13 bacteriophage DNA. Furthermore, it was found that the translocation-receptor-binding domain and toxicity domain of the colicin are able to interact with the M13 major coat protein, g8p, during bacteriophage infection. Based on these observations, we propose that interaction between colicin E7 and g8p during infection interferes with g8p depolymerizing into the cytoplasmic membrane during bacteriophage DNA penetration, thus resulting in the limited protection against M13 bacteriophage infection.
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Production of a novel and cold-active killer toxin by Mrakia frigida 2E00797 isolated from sea sediment in Antarctica.
Extremophiles
PUBLISHED: 08-03-2010
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The psychrotolerant yeast Mrakia frigida 2E00797 isolated from sea sediment in Antarctica was found to be able to produce killer toxin against the pathogenic yeast (Metschnikowia bicuspidata WCY) in crab. When the psychrotolerant yeast was grown in the medium with pH 4.5 and 3.0% (wt/vol) NaCl and at 15°C, it could produce the highest amount of killer toxin against the pathogenic yeast M. bicuspidata WCY. The crude killer toxin activity against the pathogenic yeast M. bicuspidata WCY was the highest when it grew at 15°C in the assay medium with 3.0% (wt/vol) NaCl and pH 4.5. At temperatures higher than 25°C, the killing activity produced by M. frigida 2E00797 was completely lost and after the crude killer toxin was pre-incubated at temperatures higher than 40°C for 4 h, the killing activity was also completely lost. The killer toxin produced by M. frigida 2E00797 could kill only M. bicuspidata WCY, Candida tropicalis and Candida albicans among all the fungal species and bacterial species tested in this study.
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[Biomechanical research of antegrade intramedullary fixation for the metacarpal fractures].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 07-22-2010
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To study the biomechanical characteristics of antegrade intramedullary fixation for metacarpal fractures.
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Effects of orientation on survival and growth of small fragments of the invasive, clonal plant Alternanthera philoxeroides.
PLoS ONE
PUBLISHED: 07-04-2010
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The ability of small clonal fragments to establish and grow after disturbance is an important ecological advantage of clonal growth in plants and a major factor in the invasiveness of some introduced, clonal species. We hypothesized that orientation in the horizontal position (typical for stoloniferous plants) can increase the survival and growth of dispersed clonal fragments, and that this effect of orientation can be stronger when fragments are smaller and thus have fewer reserves to support initial growth.
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[Genome sequencing and analysis of the bovine viral diarrhea virus-2 strain JZ05-1 isolated in China].
Bing Du Xue Bao
PUBLISHED: 06-25-2010
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Bovine viral diarrhea virus (BVDV) is a member of the genus Pestivirus, which is a widespread problem for beef and dairy herds, and has given rise to a significant loss in the livestock industry all over the world. The BVDV strain JZ05-1 isolated from cattle in Jilin, China generated cytopathic effect (CPE) in MDBK cells. Eight overlapped gene fragments were amplified by RT-PCR and sequenced, the complete genom sequence of BVDV strain JZ05-1 was assembled. According to the results, the JZ05-1 genome was composed of 12285 nucleotides in length (GenBank accession No. GQ888686), which could be divided into three regions: a 387 nt 5-untranslated region (UTR), a 11694 nt single large open reading frame encoding a polyprotein, and a 204 nt 3-UTR. The 5-UTR and genome sequences were analyzed by sequence alignment and construction of phylogenetic trees. The strain JZ05-1 was classified as BVDV type 2a. The BVDV-2 strain JZ05-1 genome showed high similarity to the p11Q isolated in Canada and the XJ-04 isolated in China, with 90% and 91% identity in nucleotide sequence, respectively. Compared with the similarity within the BVDV-2 genotype (96%), the JZ05-1 had low sequence similarity to other BVDV-2 strains.
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[Vitexicarpin affects proliferation and apoptosis in mutated p53 breast cancer cell].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 05-11-2010
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To elucidate the effect of proliferation and apoptosis induced by vitexicarpin in mutated p53 Hs578T cell line and study the expression of c-Myc, p21 and Bcl-2 protein in Hs578T and wild p53 MCF-7 cell pre-treated with vitexicarpin.
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[Mechanism for sperm immobilization activity of extract from Platycodon grandiflorum in vitro].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 05-09-2010
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To explore the mechanism of spermicidal effect of crude extract and platycodin-D from Platycodon grandiflorum (PG) root in vitro.
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[Regulation and mechanism of Notch signaling pathway in small cell lung cancer].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 04-15-2010
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To investigate the status of Notch signaling pathway in small cell lung cancer (SCLC).
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Posttranscriptional repression of the cel gene of the ColE7 operon by the RNA-binding protein CsrA of Escherichia coli.
Nucleic Acids Res.
PUBLISHED: 04-08-2010
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Carbon storage regulator (CsrA) is a eubacterial RNA-binding protein that acts as a global regulator of many functionally diverse chromosomal genes. Here, we reveal that CsrA represses expression from an extrachromosomal element of Escherichia coli, the lysis gene (cel) of the ColE7 operon (cea-cei-cel). This operon and colicin expression are activated upon SOS response. Disruption of csrA caused approximately 5-fold increase of the lysis protein. Gel mobility shift assays established that both the single-stranded loop of the T1 stem-loop distal to cei, and the putative CsrA binding site overlapping the Shine-Dalgarno sequence (SD) of the cel gene are important for CsrA binding. Substitution mutations at SD relieved CsrA-dependent repression of the cel gene in vivo. Steady-state levels and half-life of the cel mRNA were not affected by CsrA, implying that regulation is mediated at the translational level. Levels of CsrB and CsrC sRNAs, which bind to and antagonize CsrA, were drastically reduced upon induction of the SOS response, while the CsrA protein itself remained unaffected. Thus, CsrA is a trans-acting modulator that downregulates the expression of lysis protein, which may confer a survival advantage on colicinogenic E. coli under environment stress conditions.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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