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Factorial experiments were carried out to examine the effects of equilibration time, precooling and developmental stage on the postthaw in vitro survival of vitrified mouse embryos. Eight-cell embryos, compacted morulae, or blastocysts were cryopreserved using vitrification Solution 1 (VS1; 10% glycerol + 20% propylene glycol), and vitrification Solution 2 (VS2; 25% glycerol + 25% propylene glycol) in phosphate buffered saline + 10% calf serum. Each embryo stage group was first equilibrated in VS1 for 5, 10 or 20 min and then exposed to either a precooled ( approximately 4 degrees C) or nonprecooled ( approximately 20 degrees C) VS2 in a 0.25-ml straw before they were plunged directly into liquid nitrogen. Results of this study showed an interaction between precooling, equilibration time and developmental stage which affect significantly post-thaw embryo survival (P< 0.05). High survival rates were obtained after 10 min equilibration in VS1 irrespective of the embryo developmental stage. Precooling of the VS2 significantly improved the survival mainly of blastocysts. However, eight-cell and morula-stage embryos also showed high survival rates when they were exposed to precooled VS2 after 5 min equilibration in VS1. It was further observed that morulae usually exhibit high survival rates, and vitrification conditions are more critical for early and advanced stage embryo development. 相似文献
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Stored grains are subject to deterioration and losses through various factors, but mainly insects and fungi. Various techniques are employed to detect stored product pests; however, there is an urgent need for an industrial-scale on-line detection technique. Near-infrared hyperspectroscopic imaging and soft X-rays have shown the potential for real-time application. These techniques are particularly effective for detecting internal infestations of stored grains. The digital images of the scanned objects are analyzed for various spectral and image features using statistical techniques such as complex multivariate tools. Classification accuracies as high as 80–100 % have been achieved for various pest and grain combinations. Dual-energy X-rays have been shown to detect the concealed eggs of stored product insect pests. The main threats to stored cereals come from Aspergillus spp., Penicillium spp., and Fusarium spp., which may produce mycotoxins. These imaging techniques have shown good results in the detection of fungal infections of stored grain. 相似文献
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Polyana C Tizioto Jeremy F Taylor Jared E Decker Caio F Gromboni Mauricio A Mudadu Robert D Schnabel Luiz L Coutinho Gerson B Mour?o Priscila SN Oliveira Marcela M Souza James M Reecy Renata T Nassu Flavia A Bressani Patricia Tholon Tad S Sonstegard Mauricio M Alencar Rymer R Tullio Ana RA Nogueira Luciana CA Regitano 《遗传、选种与进化》2015,47(1)
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Marquès-Bueno MM Moreno-Romero J Abas L De Michele R Martínez MC 《The Plant journal : for cell and molecular biology》2011,67(1):169-180
Protein kinase CK2 is a pleiotropic Ser/Thr kinase, evolutionary conserved in eukaryotes. Studies performed in different organisms, from yeast to humans, have highlighted the importance of CK2 in cell growth and cell-cycle control. However, the signalling pathways in which CK2 is involved have not been fully identified. In plants, the phytohormone auxin is a major regulator of cell growth. Recent discoveries have demonstrated that differential distribution of within auxin plant tissues is essential for developmental processes, and that this distribution is dependent on polar auxin transport. We report here that a dominant-negative mutant of CK2 (CK2mut) in Arabidopsis thaliana shows phenotypic traits that are typically linked to alterations in auxin-dependent processes. However, CK2mut plants exhibit normal responses to exogenous indole-3-acetic acid (IAA) indicating that they are not affected in the perception of the hormone but upstream in the pathway. We demonstrate that mutant plants are not deficient in IAA but are impaired in its transport. Using genetic and pharmacological tools we show that CK2 activity depletion hinders correct formation of auxin gradients and leads to widespread changes in the expression of auxin-related genes. In particular, members of the auxin efflux carrier family (PINs), and the protein kinase PINOID, both key regulators of auxin fluxes, were misexpressed. PIN4 and PIN7 were also found mislocalized, with accumulation in endosomal bodies. We propose that CK2 functions in the regulation of auxin-signalling pathways, particularly in auxin transport. 相似文献
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Niyomrattanakit P Abas SN Lim CC Beer D Shi PY Chen YL 《Journal of biomolecular screening》2011,16(2):201-210
The flaviviral RNA-dependent RNA polymerase (RdRp) is an attractive drug target. To discover new inhibitors of dengue virus RdRp, the authors have developed a fluorescence-based alkaline phosphatase-coupled polymerase assay (FAPA) for high-throughput screening (HTS). A modified nucleotide analogue (2'-[2-benzothiazoyl]-6'-hydroxybenzothiazole) conjugated adenosine triphosphate (BBT-ATP) and 3'UTR-U(30) RNA were used as substrates. After the polymerase reaction, treatment with alkaline phosphatase liberates the BBT fluorophore from the polymerase reaction by-product, BBT(PPi), which can be detected at excitation and emission wavelengths of 422 and 566 nm, respectively. The assay was evaluated by examining the time dependency, assay reagent effects, reaction kinetics, and signal stability and was validated with 3'dATP and an adenosine-nucleotide triphosphate inhibitor, giving IC(50) values of 0.13 μM and 0.01 μM, respectively. A pilot screen of a diverse compound library of 40,572 compounds at 20 μM demonstrated good performance with an average Z factor of 0.81. The versatility and robustness of FAPA were evaluated with another substrate system, BBT-GTP paired with 3'UTR-C(30) RNA. The FAPA method presented here can be readily adapted for other nucleotide-dependent enzymes that generate PPi. 相似文献
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Permanaa D Abas F Maulidiani Shaari K Stanslas J Ali AM Lajis NH 《Zeitschrift für Naturforschung. C, Journal of biosciences》2005,60(7-8):523-526
A new prenylated depsidone, atrovirisidone B (2), together with naringenin (3) and 3,8"-binaringenin (4) were isolated from the roots of Garcinia atroviridis. Their structures were determined on the basis of spectral data interpretation. Compound 2 showed cytotoxic activity against human breast (MCF-7), human prostate (DU-145) and human lung (H-460) cancer cells. 相似文献
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Postural stability is crucial in maintaining body balance during quiet standing, locomotion, and any activities that require a high degree of balance performance, such as participating in sports and dancing. Research has shown that there is a relationship between stability and body mass. The aims of this study were to examine the impact that two variables had on static postural control: body mass index (BMI) and gender. Eighty healthy young adults (age=21.7±1.8 yr; height=1.65±0.09 m; mass=67.5±19.0 kg) participated in the study and the static postural control was assessed using the Biodex Balance System, with a 20 Hz sampling rate in the bipedic stance (BLS) and unipedic stance (ULS) for 30s. Five test evaluations were performed for each balance test. Postural control was found to be negatively correlated with increased adiposity, as the obese BMI group performed significantly poorer than the underweight, normal weight and overweight groups during BLS and ULS tests. The underweight, normal weight and overweight groups exhibited greater anterior-posterior stability in postural control during quiet stance. In addition, female displayed a trend of having a greater postural sway than male young adults, although it was evidenced in only some BMI groups. This study revealed that BMI do have an impact on postural control during both BLS and ULS. As such, BMI and gender-specific effects should be taken into consideration when selecting individuals for different types of sporting activities, especially those that require quiet standing. 相似文献
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Background
Postural balance is vital for safely carrying out many daily activities, such as locomotion. The purpose of this study was to determine how changes in normal standing (NS) and standing with toe-extension (SWT) impact postural control during quiet standing. Furthermore, the research aimed to examine the extent to which the effect of these factors differed between genders.Methodology/Principal Findings
Thirty healthy young adults (age = 21.2±1.3 y; height = 1.63±0.07 m; mass = 56.0±9.3 kg) with no prior lower limb injuries participated in the study. A postural stability test using the Biodex Balance System was used for both NS and SWT conditions. The three measurements from the BBS were Overall Stability Index (OSI), Medial-Lateral Stability Index (MLSI) and Anterior-Posterior Stability Index (APSI). No significant difference was found between NS and SWT in the OSI, MLSI or APSI (F 2, 28 = 3.357, p = 0.077). The main difference between the stability index scores was significant (F 2, 28 = 275.1, p<0.001). The Bonferroni post-hoc test showed significant differences between the OSI and MLSI (p<0.001); the OSI and APSI (p<0.001); and the MLSI and the APSI (p<0.001). Significant differences were found during NS (p<0.001), for the MLSI when compared with the APSI, but this was not found during the SWT condition. Additionally, no gender effects were proven to exist that altered postural sway during quiet standing.Conclusions/Significance
This study reveals significant interaction between the stability indices measured; OSI, APSI and MLSI in both NS and SWT. Standing with toe extended does not have a significant impact on an individual’s ability to control their balance during normal quiet standing. However, the findings revealed that the sway tendency in the medial-lateral direction might serve as a factor in an individual’s ability to regain balance. 相似文献10.