Overexpression of the Arabidopsis and winter squash superoxide dismutase genes enhances chilling tolerance via ABA-sensitive transcriptional regulation in transgenic Arabidopsis.

The winter squash (Cucurbita moschata, Cm) superoxide dismutase (SOD) CmSOD gene and Arabidopsis thaliana (At)SOD gene were transferred under a ubiquitin promoter into Arabidopsis via Agrobacterium tumefaciens. The expression and amount of SOD and the SOD activities in the AtSOD and CmSOD transgenic lines were significantly higher than those of non-transgenic (NT) plants exposed to 23 or 4°C treatment for 6 ~ 192-h periods. Furthermore, expressions of the cold-inducible gene (AtCBF2) and desiccation-responsible transcription factors (AtRD29A/B) were also activated in all transgenic lines compared to NT plants after chilling treatments. Compared to NT plants under chilling stress, superoxide (•O2-) accumulation was significantly lower, and chlorophyll (Chl) contents were significantly higher in all transgenic lines with higher SOD activity. Moreover, Arabidopsis seedlings overexpressing AtSOD and CmSOD also displayed greater resistance to chilling and less oxidative injury than NT plants under chilled conditions, indicating that the overexpression of AtSOD and CmSOD in Arabidopsis enhanced chilling tolerance by eliminating •O2-. The expression of AtRD29A was strongly up-regulated only in AtSOD transgenic plants treated with abscisic acid (ABA), while it was repressed in other transgenic plants, indicating ABA-sensitive AtCBF2 and AtRD29A/B transcriptional regulation signaling pathways in transgenic Arabidopsis under chilling conditions.

Enhancing the abiotic stress tolerance of plants: from chemical treatment to biotechnological approaches.

Abiotic stresses affect crop plants and cause decreases in plant quality and productivity. Plants can overcome environmental stresses by activating molecular networks, including signal transduction, stress perception, metabolite production and expressions of specific stress-related genes. Recent research suggests that chemical priming is a promising field in crop stress management because plants can be primed by chemical agents to increase their tolerance to various environmental stresses. We present a concept to meet this objective and protect plants through priming of existing defense mechanisms avoiding manipulation of the genome. In addition, recent developments in plant molecular biology include the discovery of genes related to stress tolerance, including functional genes for protecting cells and regulatory genes for regulating stress responses. Therefore, enhancing abiotic stress tolerance using a transgenic approach to transfer these genes into plant genomes has attracted more investigations. Both chemical priming agents and genetic engineering can enhance regulatory and functional genes in plants and increase stress tolerance of plants. This review summarizes the latest findings of chemical priming agents and major achievements in molecular approaches that can potentially enhance the abiotic stress tolerance of plants.

Overexpression of the ascorbate peroxidase gene from eggplant and sponge gourd enhances flood tolerance in transgenic Arabidopsis.

Previously, we found that the flood resistance of eggplant (Solanum melongena) and sponge gourd (Luffa cylindrica) enhanced ascorbate peroxidase (APX) activity under flooding, and consequently, both the SmAPX and LcAPX genes were cloned. In this study, the SmAPX and LcAPX genes were transferred under a ubiquitin promoter to Arabidopsis (At) via Agrobacterium tumefaciens. The expression and amount of APX and APX activities of the SmAPX and LcAPX transgenic lines were significantly higher than those of non-transgenic (NT) plants under a waterlogged condition. Furthermore, the SmAPX, LcAPX, At-sucrose synthases (SUS)-1, phosphoenolpyruvate carboxylase (PEPC), and lactate dehydrogenase (LDH) genes were overexpressed in all transgenic Arabidopsis lines after flooding treatment. Compared to NT plants, the malondialdehyde (MDA) contents and H2O2 accumulation were significantly lower, but germination rates were significantly higher in all transgenic lines with higher APX activity, indicating that the overexpression of SmAPX and LcAPX in Arabidopsis could enhance flood tolerance by eliminating H2O2. Moreover, Arabidopsis seedlings overexpressing SmAPX and LcAPX also displayed greater resistance to flooding and less oxidative injury than NT plants subjected to flooding condition.

Changes in sugar composition during baking and their effects on sensory attributes of baked sweet potatoes.

The objective of this study was to evaluate the influence of sugar composition on the sensory attributes of seven baked sweet potatoes. The sugar composition was analyzed using high performance liquid chromatography. Results showed that the total sugar content of baked sweet potatoes increased significantly because of the formation of maltose. The maltose content dramatically increased after baking, and became the major sugar component of baked sweet potatoes. On the other hand, baked sweet potatoes were evaluated on a 7-point hedonic scale for sensory analysis. Overall acceptability results showed that the panelists preferred baked CYY95-26 and TNG66 over the other baked varieties. Because the correlation between overall acceptability and sweetness was the highest (r = 0.69, p < 0.01), sweetness was determined as the most important factor determining the overall acceptability of baked sweet potatoes. Although sugar composition changed on baking, the overall acceptability of baked sweet potatoes was highly associated with the sucrose content.

Identification of nucleotide sequence involved in Weissellicin L production.

BACKGROUND: Weissellicin L, a novel bacteriocin produced by Weissella hellenica 4-7, was previously characterized but its full amino acid sequence remain unknown. The draft genome sequencing analysis of Weissella hellenica 4-7 was performed and the open reading frame (ORF) encoding the weissellicin L was identified and clarified. FINDINGS: The obtained results indicated that the mature bacteriocin consists of 29 amino acid residues with a molecular weight of approximately 3205.64 Da. A conserved processing site of two glycine residues in positions -1 and -2 was observed in the leader peptides. The possibility that bacteriocin secretion depended on ATP-binding cassette (ABC) transporter was therefore suggested. Furthermore, primers were designed from 5' and 3' flanking sequences of the weissellicin L structural gene. PCR presented a single product and was useful to detect weissellicin L structural gene. CONCLUSIONS: To our knowledge, this is the first report describing the full amino acid sequence of Weissellicin L. A rapid method to detect weissellicin L structural gene was also reported in this study.

Draft Genome Sequence of Lactobacillus pobuzihii E100301T.

Lactobacillus pobuzihii E100301(T) is a novel Lactobacillus species previously isolated from pobuzihi (fermented cummingcordia) in Taiwan. Phylogenetically, this strain is closest to Lactobacillus acidipiscis, but its phenotypic characteristics can be clearly distinguished from those of L. acidipiscis. We present the draft genome sequence of strain L. pobuzihii E100301(T).

Confluent focal nodular hyperplasia mimicking liver cancer: value of liver-specific contrast-enhanced MRI for diagnosis.

Focal nodular hyperplasia is the second most common benign hepatic tumor. Unlike adenoma as well as the malignant neoplasms, focal nodular hyperplasia can often be managed successfully without surgery. Use of liver-specific contrast-enhanced magnetic resonance imaging allows clinicians to confirm the diagnosis noninvasively in some patients, allowing select patients to avoid surgery. We report a case of a patient who presented with the rare profile of multiple, confluent lesions that were diagnosed, using magnetic resonance imaging with gadolinium-dimeglumine, as focal nodular hyperplasia. This complicated case was managed successfully and noninvasively based on algorithm found in the recent literature that allows patients to avoid unnecessary surgery.

[The relationship between adolescent body size and health promoting behavior and biochemical indicator factors].

BACKGROUND: Tainan City has the third highest prevalence of junior high school student obesity of all administrative districts in Taiwan. School nurses play an important role in promoting student health. Understanding the factors that significantly impact student weight is critical to designing effective student health promotion programs. PURPOSE: This study explored the relationships between health promotion behavior and serum biomarker variables and body size. METHODS: Researchers used a cross-sectional descriptive study design and stratified cluster random sampling. Subjects were 7th graders who received an in-school health checkup with blood test at 41 public junior high schools in Tainan City between July 2010 and May 2011. Research instruments included the adolescent health promotion (AHP) scale, serum biochemical profile and BMI (body mass index). Obtained data were analyzed using descriptive and inferential statistics. RESULTS: Of the 726 students who participated in this study, 22.2% were underweight and 23.8% were overweight or obese. Higher AHP scores correlated with better biomarkers and body size. Multivariate analysis found factors that increased the risk of being overweight included: being male, having a father with a relatively low level of education, playing video games frequently, and doing little or no exercise (odds ratio = 1.93, 1.75, 1.07, 1.04, respectively). IMPLICATIONS FOR PRACTICE: Participants with relatively healthy behaviors had better biomarkers and a lower risk of being overweight. Findings can support the development of evidence-based school programs to promote student health.

The differences in spiritual health between non-depressed and depressed nurses.

AIMS AND OBJECTIVES: The aim of this study was to compare the differences in spiritual health between depressed and non-depressed nurses. BACKGROUND: Previous studies have revealed that spirituality can buffer emotional pressure and maintain health, even in cases of depression. Nurses may have a tendency to develop depression; however, the relationship between depression and spirituality in nurses has been investigated only rarely. DESIGN: A correlational study. METHODS: The study was conducted using a convenience sample of 283 nurses who worked at a local hospital in northern Taiwan. We used a structured, self-administered questionnaire to obtain the data. This questionnaire included a spiritual health scale, the Beck Depression Inventory and personal data. The quantitative data were analysed using the t-test, one-way analysis of variance and logistic regression. RESULTS: All the participants were women, and 22·6% of the participants were ascertained to have depression. The non-depressed group had a higher average score for the different domains of the spiritual health scale than the depressed group. When personal and job-related variables were controlled, spirituality was a significant explanatory variable for depression. CONCLUSIONS: The spiritual health of the non-depressed nurses was better than that of the depressed nurses. The result was consistent with the previous studies on other populations. RELEVANCE TO CLINICAL PRACTICE: The spiritual health and depression of nurses should be paid attention by nursing administrators. Spiritual promoting programme in preventing depression should be examined in future researches.

Recruitment by SDF-1α of CD34-positive cells involved in sciatic nerve regeneration.

OBJECT: Increased integration of CD34(+) cells in injured nerve significantly promotes nerve regeneration, but this effect can be counteracted by limited migration and short survival of CD34(+) cells. SDF-1α and its receptor mediate the recruitment of CD34(+) cells involved in the repair mechanism of several neurological diseases. In this study, the authors investigate the potentiation of CD34(+) cell recruitment triggered by SDF-1α and the involvement of CD34(+) cells in peripheral nerve regeneration. METHODS: Peripheral nerve injury was induced in 147 Sprague-Dawley rats by crushing the left sciatic nerve with a vessel clamp. The animals were allocated to 3 groups: Group 1, crush injury (controls); Group 2, crush injury and local application of SDF-1α recombinant proteins; and Group 3, crush injury and local application of SDF-1α antibody. Electrophysiological studies and assessment of regeneration markers were conducted at 4 weeks after injury; neurobehavioral studies were conducted at 1, 2, 3, and 4 weeks after injury. The expression of SDF-1α, accumulation of CD34(+) cells, immune cells, and angiogenesis factors in injured nerves were evaluated at 1, 3, 7, 10, 14, 21, and 28 days after injury. RESULTS: Application of SDF-1α increased the migration of CD34(+) cells in vitro, and this effect was dose dependent. Crush injury induced the expression of SDF-1α, with a peak of 10-14 days postinjury, and this increased expression of SDF-1α paralleled the deposition of CD34(+) cells, expression of VEGF, and expression of neurofilament. These effects were further enhanced by the administration of SDF-1α recombinant protein and abolished by administration of SDF-1α antibody. Furthermore, these effects were consistent with improvement in measures of neurological function such as sciatic function index, electrophysiological parameters, muscle weight, and myelination of regenerative nerve. CONCLUSIONS: Expression of SDF-1α facilitates recruitment of CD34(+) cells in peripheral nerve injury. The increased deposition of CD34(+) cells paralleled significant expression of angiogenesis factors and was consistent with improvement of neurological function. Utilization of SDF-1α for enhancing the recruitment of CD34(+) cells involved in peripheral nerve regeneration may be considered as an alternative treatment strategy in peripheral nerve disorders.

Peripheral nerve regeneration using a microporous polylactic acid asymmetric conduit in a rabbit long-gap sciatic nerve transection model.

The performance of an asymmetric conduit made of microporous polylactic acid (PLA) in promoting the long-term peripheral nerve regeneration across a 20-mm-long sciatic nerve gap was evaluated by a rabbit sciatic nerve transection model. Magnetic resonance imaging (MRI) was employed to monitor the nerve regeneration process. The extents of nerve regeneration and conduit degradation were quantified by image analysis. Functional and histological analyses were followed to assess nerve reinnervation. MR images showed that the transected nerve was connected at about 4 months. The diameter of the regenerated nerve continued to increase while the conduit was gradually degraded. The conduit was completely degraded in 18 months. The degradation kinetics in vivo was estimated based on MR images. The functional recovery after 18 months was ∼82% based on electrophysiology. The extension range of the operated limb was slowly recuperated to ∼81% at 18 months. Histology showed that nerve bundles were self-assembled after 16-18 months, but the morphologies were still different from those of normal sciatic nerve. This was the first work on the long-term evaluation of peripheral nerve regeneration in a rabbit model, and the first to report the use of MRI to obtain the real-time images of regenerated nerve in a biomaterial conduit as well as to define the degradation rate of the conduit in vivo. The platform established in this study serves to evaluate the regeneration of larger-diameter (>3-mm) nerve across a long-gap bridged by a conduit.

Correction of left ventricular wall thickening from short-axis cine MRI for basal-descent through-plane motion.

PURPOSE: To solve the problem of the basal descent movement in quantification of the regional left ventricular (LV) myocardial wall thickness (WTh) and wall thickening (%WT) in short-axis (SA) cine MRI for effectively assessing the regional wall motion of LV myocardium. MATERIALS AND METHODS: LV long-axis tagged MRI and SA cine MRI were performed to calculate the longitudinal translation and circumferential WTh of LV myocardium in eight normal volunteers. The new SA end-systolic thickness (EST) data were reconstructed from the original EST data, based on the quantified longitudinal translation of LV myocardium. RESULTS: The mean %WT of six segments in the basal section after correction was significantly different from that before correction in both intra- and inter-operator experiments. The polar map also showed the significant improvement of the variability of regional %WT and lack of quantification of %WT in the most basal SA slices after correction. CONCLUSION: The proposed technique demonstrated an important advantage to calculate the %WT in the most basal SA myocardial tissue, which was considered difficult to be achieved using cine MRI.

Quantitative analysis in clinical applications of brain MRI using independent component analysis coupled with support vector machine.

PURPOSE: To effectively perform quantification of brain normal tissues and pathologies simultaneously, independent component analysis (ICA) coupled with support vector machine (SVM) is investigated and evaluated for effective volumetric measurements of normal and lesion tissues using multispectral MR images. MATERIALS AND METHODS: Synthetic and real MR data of normal brain and white matter lesion (WML) data were used to evaluate the accuracy and reproducibility of gray matter (GM), white matter (WM), and WML volume measurements by using the proposed ICA+SVM method to analyze three sets of MR images, T1-weighted, T2-weighted, and proton density/fluid-attenuated inversion recovery images. RESULTS: The Tanimoto indexes of GM/WM classification in the normal synthetic data calculated by the ICA+SVM method were 0.82/0.89 for data with 0% noise level. As for clinical MR data experiments, the ICA+SVM method clearly extracted the normal tissues and white matter hyperintensity lesions from the MR images, with low intra- and inter-operator coefficient of variations. CONCLUSION: The experiments conducted provide evidence that the ICA+SVM method has shown promise and potential in applications to classification of normal and pathological tissues in brain MRI.

Spiritual health, clinical practice stress, depressive tendency and health-promoting behaviours among nursing students.

AIM: This paper is a report of an exploration of the association of spiritual health with clinical practice stress, depressive tendency and health-promoting behaviours among nursing students. BACKGROUND: Several studies in western countries have demonstrated an association between spirituality and health. Spirituality-related research in eastern countries, however, is still in its infancy. METHODS: A cross-sectional design was adopted and structured questionnaires were used for data collection. We adopted the Probability Proportional to Size cluster sampling method to recruit nursing students in senior grades. Data were collected in 2005 using the Spiritual Health Scale, Perceived Clinical Practice Stress Scale, Beck Depression Inventory-II and Health Promotion Behaviours Scale. RESULTS: A total of 1276 nursing students with an average age of 20.1 years (sd = 1.6 years) participated in the study. Spiritual health was negatively associated with clinical practice stress (r = -0.211, P < 0.001) and depressive tendency (r = -0.324, P < 0.001) and positively associated with health-promoting behaviours (r = 0.611, P < 0.001). Using hierarchical regression analysis to control for demographic factors, spiritual health was found to be an important predictive factor for clinical practice stress, depressive tendency and health-promoting behaviours. CONCLUSION: These results are consistent with research findings from western countries. Educators should develop strategies to address nursing students' spiritual health. This may help nursing students to manage their stress, to reduce depressive symptoms and to enhance health-promoting behaviours.

Characterization of focal brain lesions by gradient-echo arterial spin-tagging perfusion imaging.

A simple gradient-echo arterial spin tagging (GREAST) technique allows for quick assessment of regional tissue perfusion without the need for exogenous contrast agent. The purpose of this prospective study was to validate GREAST imaging in characterizing the regional perfusion status of focal brain lesions by comparing with relative cerebral blood volume (rCBV) maps obtained by using echo-planar imaging (EPI)-based dynamic susceptibility contrast MR imaging. Thirty-two patients whose nonenhanced brain MR images showed 34 focal brain lesions during routine examination were selected to immediately undergo GREAST and dynamic susceptibility contrast MR imaging to evaluate regional perfusion of the lesions. The Pearson correlation coefficient was used to test the relative quantification of local perfusion with the two imaging methods. Qualitative perfusion measurements agreed in 23 (79%) of 29 lesions for which GREAST and dynamic susceptibility contrast MR imaging were successful. On rCBV maps, six focal lesions with local hemorrhage were underestimated. In three patients with metal surgical implants, lesions could not be measured because of susceptibility artifacts and distortion on EPIs. After these lesions were excluded, the Pearson correlation coefficient between relative quantitative perfusion measurements on GREAST images versus rCBV maps was about 0.90 (p value = 0.000). The success rate of GREAST imaging was 94% (30 of 32 patients), higher than that of dynamic susceptibility contrast MR imaging (72%, or 23 of 32 patients). GREAST imaging was comparable to rCBV mapping for the relative quantification of regional perfusion of focal brain lesions. This technique may be useful in routine MR examination for characterizing the regional perfusion of brain focal lesions.

Interaction between rice MYBGA and the gibberellin response element controls tissue-specific sugar sensitivity of alpha-amylase genes.

Expression of alpha-amylase genes during cereal grain germination and seedling growth is regulated negatively by sugar in embryos and positively by gibberellin (GA) in endosperm through the sugar response complex (SRC) and the GA response complex (GARC), respectively. We analyzed two alpha-amylase promoters, alphaAmy3 containing only SRC and alphaAmy8 containing overlapped SRC and GARC. alphaAmy3 was sugar-sensitive but GA-nonresponsive in both rice (Oryza sativa) embryos and endosperms, whereas alphaAmy8 was sugar-sensitive in embryos and GA-responsive in endosperms. Mutation of the GA response element (GARE) in the alphaAmy8 promoter impaired its GA response but enhanced sugar sensitivity, and insertion of GARE in the alphaAmy3 promoter rendered it GA-responsive but sugar-insensitive in endosperms. Expression of the GARE-interacting transcription factor MYBGA was induced by GA in endosperms, correlating with the endosperm-specific alphaAmy8 GA response. alphaAmy8 became sugar-sensitive in MYBGA knockout mutant endosperms, suggesting that the MYBGA-GARE interaction overrides the sugar sensitivity of alphaAmy8. In embryos overexpressing MYBGA, alphaAmy8 became sugar-insensitive, indicating that MYBGA affects sugar repression. alpha-Amylase promoters active in endosperms contain GARE, whereas those active in embryos may or may not contain GARE, confirming that the GARE and GA-induced MYBGA interaction prevents sugar feedback repression of endosperm alpha-amylase genes. We demonstrate that the MYBGA-GARE interaction affects sugar feedback control in balanced energy production during seedling growth and provide insight into the control mechanisms of tissue-specific regulation of alpha-amylase expression by sugar and GA signaling interference.