Transformation and Regeneration of Taro with Two Plant Disease Resistance Genes: A Rice Chitinase Gene and a Wheat Oxalate Oxidase Gene

Taro {Colocasia esculenta) is one of the most important crops in the Pacific Islands. However, taro yields have been declining in Hawaii over the past 30 years due to diseases caused by oomycete and fungal pathogens. Chitin, an important structural component of the cell wall of most fungi, is hydrolyzed by the action of the enzyme chitinase. Plants transformed with a chitinase gene have shown increased resistance to several fungal pathogens. Oxalate oxidase, which converts oxalic acid and O2 to CO2 and H2O2 , has been shown to be involved in plant resistance to pathogens. Transformation of plants with an oxalate oxidase gene has increased their resistance to fungal pathogens. An efficient regeneration and transformation system of the taro cultivar Bun Long has been developed. Regenerable calli were induced on MS medium with 2 mg L-1 BA and 1 mg L-1 NAA (M5 medium). Multiple shoots from these calli were induced on MS medium supplemented with 4 mg L-1 BA (M15 medium). The rice chitinase gene (RICCHIll) was introduced into taro calli using particle bombardment. Analyses using polymerase chain reaction (PCR) and Southern blot confirmed the presence of the rice chitinase gene in one transgenic line. Agrobacterium tumefaciens-mediated transformation using two plant disease resistance genes: a rice chitinase gene (RICCHIl 1) and a wheat oxalate oxidase gene (gf2.8) were developed. Two hundred calli were infected with the supervirulent A. tumefaciens strain EHA105 harboring the plant transformation plasmid pBI121:RICCHI11. Six lines were shown to contain the rice chitinase gene using the PCR and Southern blot analyses. Transformation was also conducted using EHA105:pB1121:gf2.8 that contains the wheat oxalate oxidase gene gf2.8. Two independent lines were shown to be positive for the specific gf2.8 gene fragment using PCR, Southern blot and RT-PCR analyses, indicating the presence and transcription of gf2.8 gene in the transformed lines. In a preliminary bioassay, six transgenic taro lines with the rice chitinase gene exhibited tolerance to the fungal pathogen Sclerotium rolfsii. One transgenic taro line with the wheat oxalate oxidase gene showed tolerance to both the fungal pathogen Sclerotium rolfsii and oomycete pathogen Phytophthora colocasiae. To our knowledge, this is the first report of taro transformed with disease resistance genes. In addition, this is the first report of genetically engineered taro that exhibited disease tolerance in preliminary bioassays

Modal Decoupling Using the Method of Weighted Residuals for the Nonlinear Elastic Dynamics of a Clamped Laminated Composite

We develop an approach to reduce the governing equation of motion for the nonlinear vibration of a clamped laminated composite to the Duffing equation in a decoupled modal form. The method of weighted residuals enables such a reduction for laminates with clamped boundary conditions. Both rigidly clamped and loosely clamped boundary conditions are analyzed using this method. The reduction method conserves the total energy of the system. The decoupled modal form Duffing equation has constant modal parameters in terms of the laminated composite material's properties and geometries. The numerical computations illustrate the individual modal response with an emphasis of the transitional phenomena to chaos caused by the large load

PO-151 The change characteristics of precompetition biochemical indexes of excellent male gymnasts

Objective In order to ensure that Chinese gymnasts in Hubei province can adapt to the pattern of large intensity and large training volume before the national games in good condition, the training monitoring and regulation of athletes' physical function and fatigue recovery are carried out by monitoring blood, urine and other biochemical indicators. On this basis, the characteristics of the physical and biochemical functions of the gymnasts in Hubei province are summarized, hoping to provide the accumulated data of the physical function evaluation of the gymnasts in the future, and to strengthen the scientific degree of the gymnastics training in Hubei province.  Methods To prepare for the national games in 2017, 12 men gymnastics athletes of Hubei province as the research object, and in the precompetition training period, every Monday morning test hemoglobin(Hb), white blood cells(WBC), blood urea(BUN), creatine kinase(CK), every two weeks on Monday morning test testosterone, cortisol, and body composition, test every two weeks training on the second day of urine 10 items such as indexes. Blood samples and urine samples were sent to the laboratory of the laboratory of Tongji Hospital in Wuhan city and Hubei institute of sports science, respectively. Results 1. The WBC of male gymnasts in Hubei province was between 3.6~11.7×109 /L, with an average value of 5.7 ±1.4 ×109/L, and the WBC level was within the normal range with a small range of variation, with no significant difference in each test. In the experiment, we found that there were large individual differences in the low WBC. Individual athletes' WBC was high for a long time, indicating weak resistance and easy to have inflammatory infection. In addition, the WBC of some athletes is low for a long time, and it is difficult to recover. Although the targeted treatment is improved, it is easy to relapse. Therefore, in sports practice, attention should be paid to WBC detection and long-term monitoring of susceptible athletes. The Hb level of male gymnasts in Hubei province is between 131~175 g/L, with an average of 156.3±8.1 g/L, and that of Chinese excellent male gymnasts is 156.9 ± 8.83 g/L, indicating that the Hb level of male gymnasts in Hubei province is relatively high compared with the project itself. In the early stage of large amount of exercise, Hb concentration will decrease. With the adaptation to the training amount, Hb concentration gradually rises, which is reflected in the improvement of functional state and the improvement of sports ability. The change range of serum CK was between 118~594 U/L, with an average of 282.4 ±105.2 U/L, which was relatively high. CK changes obviously with the training intensity, and the period of high-intensity training is significantly higher than the adjustment period, and there is a trend of accumulation with the extension of training time. The change range of BUN was between 3.19~7.23 mmol/L, with an average value of 5.15± 1.04 mmol/L, and the average value of each stage of precompetition training was between 4.5-5.5 mmol/L, with no significant change and no statistical difference. The change range of serum testosterone was between  3.03~9.69ng/mL, with an average of 5.45 ±1.29ng/mL, and the overall level of testosterone was low. Serum cortisol changes ranged from 7.5 to 24.9 ug/dL, with an average of 14.5 ±3.3ug/dL, and the overall level was stable. After a long period of intensive training, testosterone levels declined and cortisol did not change significantly. In the test of ten urine items, there were 10 cases of urinogen positive, 2 cases of bilirubin, and 1 case of urinary protein. Conclusions 1. The WBC level of gymnasts in Hubei province is within the normal range and the variation range is small. Studies have shown that adaptive exercise can improve disease resistance, but in fact the athletes are less resistant at late periods of heavy duty training, before or during competition, and the risk of various diseases increases. In sports practice, WBC testing should be emphasized, and athletes with low immunity should be monitored for a long time. Athlete's Hb level is at a higher level relative to the project itself and combined with training. Starting from the end of winter training in February, athlete's Hb level is significantly decreased, reflecting the decrease of Hb when the intensity is on the upper level. At the same time, the individual difference of athletes' Hb level is large. Hb level will produce a great impact on the aerobic capacity of athletes, although aerobic capacity is not gymnastics technology projects focus on the development of special technical ability, but high aerobic capacity of athletes than aerobic athletes are more able to withstand the great physiological load of exercise, poor ability of aerobic capacity of athletes in training is usually poor second half for a longer time, prone to pay enough concentration, movement quality decreased obviously, can't do difficult moves. The CK level of gymnasts in Hubei province is at a relatively high level, which is related to the characteristics of gymnastics. The precompetition training of gymnastics mainly highlights the intensity load, the intensity of strength training is relatively high, and the muscle cell membrane is damaged more. The differences of serum CK in the period of high-intensity training and adjustment are significant, which can reflect the intensity of precompetition training, as well as the fatigue and recovery of athletes. The changes of blood urea were not obvious at each training stage before the competition, and there was no significant reaction of blood urea accumulation. There was no significant difference between the intensity training stage and the adjustment period, indicating that blood urea was not a sensitive fatigue index in the strength training. In addition, when athletes lose weight before the competition, it is easy to see increased blood urea. The overall level of serum testosterone of gymnasts in Hubei province is relatively low, indicating that the muscle strength and explosive power of gymnasts in Hubei province are relatively weak. Cortisol is relatively stable, suggesting that the body's resilience is modest. After the intensive training, the positive rate of urobiogen is much higher than that of urinary protein and bilirubin, indicating that urobiogen is more sensitive to the evaluation of the intensity of training in gymnastics

Long term water integration in interconnected ramets of stoloniferous grass, buffalograss

Buffalograss (Buchloë dactyloides) is known for its drought resistant character. Natural resources are patchily distributed and resource sharing between interconnected ramets can enhance the performance of the whole genet. In order to examine whether there exists long term water integration between interconnected ramets of buffalograss, a greenhouse experiment was conducted. Interconnected ramet pairs of stoloniferous buffalograss were planted in two partitioned similar-sized containers and subjected to homogeneous (20 ml pot-1 d-1 or 100 - 150 ml pot-1 d-1) or heterogeneous (20 ml pot-1 d-1 vs. 100-150 ml pot-1 d-1) water supply; the whole experiment lasted for 91 days. In heterogeneous treatment, water translocation was equally effective in acropetal and basipetal directions. Elder ramet was more efficient in water use, but rooted ramet of elder ramet in moist condition experienced significant cost when it was connected to younger ramet in dry condition; whereas, no cost was found in any fragment of younger donor ramet. Ramet in dry condition produced more biomass than its connected ramet in moist condition and developed larger leaves. This “oversharing” phenomenon indicated that no net cost was involved in water integration, and water might not be the only resources transported within stolon xylem. Overall, long term water integration is an important strategy for buffalograss to cope with adverse natural drought conditions.Keywords: Water integration, interconnected ramets, heterogeneous treatment, Buchloë dactyloides, oversharingAfrican Journal of Biotechnology Vol. 9(34), pp. 5503-5510, 23 August, 201

Secreted factors from olfactory mucosa cells expanded as free-floating spheres increase neurogenesis in olfactory bulb neurosphere cultures.

BACKGROUND: The olfactory epithelium is a neurogenic tissue comprising a population of olfactory receptor neurons that are renewed throughout adulthood by a population of stem and progenitor cells. Because of their relative accessibility compared to intra-cranially located neural stem/progenitor cells, olfactory epithelium stem and progenitor cells make attractive candidates for autologous cell-based therapy. However, olfactory stem and progenitor cells expand very slowly when grown as free-floating spheres (olfactory-spheres) under growth factor stimulation in a neurosphere assay. RESULTS: In order to address whether olfactory mucosa cells extrinsically regulate proliferation and/or differentiation of immature neural cells, we cultured neural progenitor cells derived from mouse neonatal olfactory bulb or subventricular zone (SVZ) in the presence of medium conditioned by olfactory mucosa-derived spheres (olfactory-spheres). Our data demonstrated that olfactory mucosa cells produced soluble factors that affect bulbar neural progenitor cell differentiation but not their proliferation when compared to control media. In addition, olfactory mucosa derived soluble factors increased neurogenesis, especially favouring the generation of non-GABAergic neurons. Olfactory mucosa conditioned medium also contained several factors with neurotrophic/neuroprotective properties. Olfactory-sphere conditioned medium did not affect proliferation or differentiation of SVZ-derived neural progenitors. CONCLUSION: These data suggest that the olfactory mucosa does not contain factors that are inhibitory to neural stem/progenitor cell proliferation but does contain factors that steer differentiation toward neuronal phenotypes. Moreover, they suggest that the poor expansion of olfactory-spheres may be in part due to intrinsic properties of the olfactory epithelial stem/progenitor cell population.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Secreted factors from olfactory mucosa cells expanded as free-floating spheres increase neurogenesis in olfactory bulb neurosphere cultures

<p>Abstract</p> <p>Background</p> <p>The olfactory epithelium is a neurogenic tissue comprising a population of olfactory receptor neurons that are renewed throughout adulthood by a population of stem and progenitor cells. Because of their relative accessibility compared to intra-cranially located neural stem/progenitor cells, olfactory epithelium stem and progenitor cells make attractive candidates for autologous cell-based therapy. However, olfactory stem and progenitor cells expand very slowly when grown as free-floating spheres (olfactory-spheres) under growth factor stimulation in a neurosphere assay.</p> <p>Results</p> <p>In order to address whether olfactory mucosa cells extrinsically regulate proliferation and/or differentiation of immature neural cells, we cultured neural progenitor cells derived from mouse neonatal olfactory bulb or subventricular zone (SVZ) in the presence of medium conditioned by olfactory mucosa-derived spheres (olfactory-spheres). Our data demonstrated that olfactory mucosa cells produced soluble factors that affect bulbar neural progenitor cell differentiation but not their proliferation when compared to control media. In addition, olfactory mucosa derived soluble factors increased neurogenesis, especially favouring the generation of non-GABAergic neurons. Olfactory mucosa conditioned medium also contained several factors with neurotrophic/neuroprotective properties. Olfactory-sphere conditioned medium did not affect proliferation or differentiation of SVZ-derived neural progenitors.</p> <p>Conclusion</p> <p>These data suggest that the olfactory mucosa does not contain factors that are inhibitory to neural stem/progenitor cell proliferation but does contain factors that steer differentiation toward neuronal phenotypes. Moreover, they suggest that the poor expansion of olfactory-spheres may be in part due to intrinsic properties of the olfactory epithelial stem/progenitor cell population.</p

Hybrid composites of silica glass fibre/nano-hydroxyapatite/polylactic acid for medical application

Fibre reinforced composites (FRC) have shown great potential for the application of internal bone fixation due to mechanical properties that are similar to those of human cortical bones. Ternary composites of silica glass fibres, nano-hydroxyapatite (n-HA) and polylactic acid (PLA) were prepared by compression moulding and their mechanical properties were characterized in this study. With the volumetric content of glass fibre remained constantly at 30% and the volume fraction of n-HA increased from 0% to 5%, the flexural strengths of composites decreased from 625.68 MPa to 206.55 MPa, whereas a gradual increment of flexural modulus from 11.01 to 14.08 GPa were observed at the same time. Within a 28-day degradation period, the flexural strengths decreased by 30%, while no obvious trend of modulus variation was found. The flexural properties of all composites prepared in this study were all found to be close to the reported flexural properties. On the other hand, as more n-HA were incorporated, the water absorption percentages increased, whereas negligible mass loss were recorded. SEM images revealed that the impregnation of fibre mats was poor as loose fibres were observed, which shall be solved in future research to further improve the mechanical properties as well as endurance against degradation. © 2017 International Committee on Composite Materials. All rights reserved