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901.
Hala Badr Khalil Sabrina C Brunetti Uyen Minh Pham Deborah Maret André Laroche Patrick J Gulick 《BMC genomics》2014,15(1)
Background
The caleosin genes encode proteins with a single conserved EF hand calcium-binding domain and comprise small gene families found in a wide range of plant species. Some members of the gene family have been shown to be upregulated by environmental stresses including low water availability and high salinity. Caleosin 3 from wheat has been shown to interact with the α-subunit of the heterotrimeric G proteins, and to act as a GTPase activating protein (GAP). This study characterizes the size and diversity of the gene family in wheat and related species and characterizes the differential tissue-specific expression of members of the gene family.Results
A total of 34 gene family members that belong to eleven paralogous groups of caleosins were identified in the hexaploid bread wheat, T. aestivum. Each group was represented by three homeologous copies of the gene located on corresponding homeologous chromosomes, except the caleosin 10, which has four gene copies. Ten gene family members were identified in diploid barley, Hordeum vulgare, and in rye, Secale cereale, seven in Brachypodium distachyon, and six in rice, Oryza sativa. The analysis of gene expression was assayed in triticale and rye by RNA-Seq analysis of 454 sequence sets and members of the gene family were found to have diverse patterns of gene expression in the different tissues that were sampled in rye and in triticale, the hybrid hexaploid species derived from wheat and rye. Expression of the gene family in wheat and barley was also previously determined by microarray analysis, and changes in expression during development and in response to environmental stresses are presented.Conclusions
The caleosin gene family had a greater degree of expansion in the Triticeae than in the other monocot species, Brachypodium and rice. The prior implication of one member of the gene family in the stress response and heterotrimeric G protein signaling, points to the potential importance of the caleosin gene family. The complexity of the family and differential expression in various tissues and under conditions of abiotic stress suggests the possibility that caleosin family members may play diverse roles in signaling and development that warrants further investigation.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-239) contains supplementary material, which is available to authorized users. 相似文献902.
A multi-residue method using dispersive solid phase extraction and gas chromatography with mass spectrometric detection has been developed for determination of trace levels of 103 pesticides, including organophosphate, organochlorine, carbamate, and pyrethroid compounds in agricultural soil. Dispersive solid phase extraction using 10 mL of acetonitrile for 3 min of extraction time showed satisfactory extraction efficiency. Recoveries of pesticides from fortified agricultural soil samples ranged from 65% to 117% for three different fortified levels of 50, 100, and 500 μg/kg and relative standard deviations of the recoveries are below 19%. Detection and quantification limits ranged from 1 to 13 μg/kg and from 3 to 38 μg/kg, respectively. The proposed method was less time-consuming, safer, and easy to use for routine analysis. 相似文献
903.
Misol Ahn Krystyna Bajsarowicz Abby Oehler Azucena Lemus Krystof Bankiewicz Stephen J. DeArmond 《PloS one》2014,9(5)
Prion disease is caused by a single pathogenic protein (PrPSc), an abnormal conformer of the normal cellular prion protein PrPC. Depletion of PrPC in prion knockout mice makes them resistant to prion disease. Thus, gene silencing of the Prnp gene is a promising effective therapeutic approach. Here, we examined adeno-associated virus vector type 2 encoding a short hairpin RNA targeting Prnp mRNA (AAV2-PrP-shRNA) to suppress PrPC expression both in vitro and in vivo. AAV2-PrP-shRNA treatment suppressed PrP levels and prevented dendritic degeneration in RML-infected brain aggregate cultures. Infusion of AAV2-PrP-shRNA-eGFP into the thalamus of CD-1 mice showed that eGFP was transported to the cerebral cortex via anterograde transport and the overall PrPC levels were reduced by ∼70% within 4 weeks. For therapeutic purposes, we treated RML-infected CD-1 mice with AAV2-PrP-shRNA beginning at 50 days post inoculation. Although AAV2-PrP-shRNA focally suppressed PrPSc formation in the thalamic infusion site by ∼75%, it did not suppress PrPSc formation efficiently in other regions of the brain. Survival of mice was not extended compared to the untreated controls. Global suppression of PrPC in the brain is required for successful therapy of prion diseases. 相似文献
904.
905.
So-Yeon Lee Jinho Yu Kang-Mo Ahn Kyung Won Kim Youn Ho Shin Kyung-shin Lee Seo Ah Hong Young-ho Jung Eun Lee Song-I Yang Ju-hee Seo Ji-Won Kwon Byoung-Ju Kim Hyo-Bin Kim Woo-Kyung Kim Dae Jin Song Gwang Cheon Jang Jung Yeon Shim Soo-Young Lee Ja-Young Kwon Suk-Joo Choi Kyung-Ju Lee Hee Jin Park Hye-Sung Won Ho-Sung Yoo Mi-Jin Kang Hyung-Young Kim Soo-Jong Hong 《PloS one》2014,9(5)
Background
Although cesarean delivery and prenatal exposure to antibiotics are likely to affect the gut microbiome in infancy, their effect on the development of atopic dermatitis (AD) in infancy is unclear. The influence of individual genotypes on these relationships is also unclear. To evaluate with a prospective birth cohort study whether cesarean section, prenatal exposure to antibiotics, and susceptible genotypes act additively to promote the development of AD in infancy.Methods
The Cohort for Childhood of Asthma and Allergic Diseases (COCOA) was selected from the general Korean population. A pediatric allergist assessed 412 infants for the presence of AD at 1 year of age. Their cord blood DNA was subjected to interleukin (IL)-13 (rs20541) and cluster-of-differentiation (CD)14 (rs2569190) genotype analysis.Results
The combination of cesarean delivery and prenatal exposure to antibiotics associated significantly and positively with AD (adjusted odds ratio, 5.70; 95% CI, 1.19–27.3). The association between cesarean delivery and AD was significantly modified by parental history of allergic diseases or risk-associated IL-13 (rs20541) and CD14 (rs2569190) genotypes. There was a trend of interaction between IL-13 (rs20541) and delivery mode with respect to the subsequent risk of AD. (P for interaction = 0.039) Infants who were exposed prenatally to antibiotics and were born by cesarean delivery had a lower total microbiota diversity in stool samples at 6 months of age than the control group. As the number of these risk factors increased, the AD risk rose (trend p<0.05).Conclusion
Cesarean delivery and prenatal antibiotic exposure may affect the gut microbiota, which may in turn influence the risk of AD in infants. These relationships may be shaped by the genetic predisposition. 相似文献906.
Keisuke Kuwahara Teppei Imai Akiko Nishihara Tohru Nakagawa Shuichiro Yamamoto Toru Honda Toshiaki Miyamoto Takeshi Kochi Masafumi Eguchi Akihiko Uehara Reiko Kuroda Daisuke Omoto Kayo Kurotani Ngoc Minh Pham Akiko Nanri Isamu Kabe Tetsuya Mizoue Naoki Kunugita Seitaro Dohi Japan Epidemiology Collaboration on Occupational Health Study Group 《PloS one》2014,9(5)
Objective
Epidemiologic evidence on long working hour and diabetes has been conflicting. We examined the association between overtime work and prevalence of diabetes among Japanese workers.Methods
The subjects were 40,861 employees (35,170 men and 5,691 women), aged 16 to 83 years, of 4 companies in Japan. Hours of overtime were assessed using self-reported questionnaires. Diabetes was defined as a fasting plasma glucose ≥126 mg/dl (7.0 mmol/l), hemoglobin A1c ≥6.5% (48 mmol/mol), or current use of anti-diabetic drug. Multiple logistic regression analysis was used to calculate odds ratio of diabetes for each category of overtime.Results
After adjustment for age, sex, company, smoking, and BMI, there was a suggestion of U-shaped relationship between overtime work and prevalence of diabetes (P for quadratic trend = 0.07). Compared with those who worked <45 hours of overtime per month, the adjusted odds ratios (95% confidence interval) of diabetes were 0.86 (0.77–0.94), 0.69 (0.53–0.89), and 1.03 (0.72–1.46) for those who worked 45–79, 80–99, and ≥100 hours of overtime per month, respectively. In one company (n = 33,807), where other potential confounders including shift work, job position, type of department, alcohol consumption, sleep duration, leisure time physical activity, and family history of diabetes was additionally adjusted for, similar result was obtained (P for quadratic trend = 0.05).Conclusions
Long hours of overtime work may not be associated with increased prevalence of diabetes among Japanese workers. 相似文献907.
Hak Jun Ahn Kang Il Kim Nguyen Ngoc Hoan Churl Ho Kim Eunpyo Moon Kyeong Sook Choi Sang Sik Yang Jong-Soo Lee 《PloS one》2014,9(1)
The plasma jet has been proposed as a novel therapeutic method for cancer. Anticancer activity of plasma has been reported to involve mitochondrial dysfunction. However, what constituents generated by plasma is linked to this anticancer process and its mechanism of action remain unclear. Here, we report that the therapeutic effects of air plasma result from generation of reactive oxygen/nitrogen species (ROS/RNS) including H2O2, Ox, OH−, •O2, NOx, leading to depolarization of mitochondrial membrane potential and mitochondrial ROS accumulation. Simultaneously, ROS/RNS activate c-Jun NH2-terminal kinase (JNK) and p38 kinase. As a consequence, treatment with air plasma jets induces apoptotic death in human cervical cancer HeLa cells. Pretreatment of the cells with antioxidants, JNK and p38 inhibitors, or JNK and p38 siRNA abrogates the depolarization of mitochondrial membrane potential and impairs the air plasma-induced apoptotic cell death, suggesting that the ROS/RNS generated by plasma trigger signaling pathways involving JNK and p38 and promote mitochondrial perturbation, leading to apoptosis. Therefore, administration of air plasma may be a feasible strategy to eliminate cancer cells. 相似文献
908.
W. Keith Miskimins Hyun Joo Ahn Ji Yeon Kim Sun Ryu Yuh-Seog Jung Joon Young Choi 《PloS one》2014,9(1)
Phenformin (phenethylbiguanide; an anti-diabetic agent) plus oxamate [lactate dehydrogenase (LDH) inhibitor] was tested as a potential anti-cancer therapeutic combination. In in vitro studies, phenformin was more potent than metformin, another biguanide, recently recognized to have anti-cancer effects, in promoting cancer cell death in the range of 25 times to 15 million times in various cancer cell lines. The anti-cancer effect of phenformin was related to complex I inhibition in the mitochondria and subsequent overproduction of reactive oxygen species (ROS). Addition of oxamate inhibited LDH activity and lactate production by cells, which is a major side effect of biguanides, and induced more rapid cancer cell death by decreasing ATP production and accelerating ROS production. Phenformin plus oxamate was more effective than phenformin combined with LDH knockdown. In a syngeneic mouse model, phenformin with oxamate increased tumor apoptosis, reduced tumor size and 18F-fluorodeoxyglucose (FDG) uptake on positron emission tomography/computed tomography compared to control. We conclude that phenformin is more cytotoxic towards cancer cells than metformin. Furthermore, phenformin and oxamate have synergistic anti-cancer effects through simultaneous inhibition of complex I in the mitochondria and LDH in the cytosol, respectively. 相似文献
909.
Tuan D. Pham 《PloS one》2014,9(8)
The modeling of the spatial distribution of image properties is important for many pattern recognition problems in science and engineering. Mathematical methods are needed to quantify the variability of this spatial distribution based on which a decision of classification can be made in an optimal sense. However, image properties are often subject to uncertainty due to both incomplete and imprecise information. This paper presents an integrated approach for estimating the spatial uncertainty of vagueness in images using the theory of geostatistics and the calculus of probability measures of fuzzy events. Such a model for the quantification of spatial uncertainty is utilized as a new image feature extraction method, based on which classifiers can be trained to perform the task of pattern recognition. Applications of the proposed algorithm to the classification of various types of image data suggest the usefulness of the proposed uncertainty modeling technique for texture feature extraction. 相似文献
910.