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Siddarth Srinivasan Ioana D. Vladescu Stephan A. Koehler Xiaoling Wang Madhav Mani Shmuel M. Rubinstein 《Biophysical journal》2018,114(6):1490-1498
Bacterial biofilms are surface-attached microbial communities encased in self-produced extracellular polymeric substances. Here we demonstrate that during the development of Bacillus subtilis biofilms, matrix production is localized to an annular front propagating at the periphery and sporulation to a second front at a fixed distance at the interior. We show that within these fronts, cells switch off matrix production and transition to sporulation after a set time delay of ~100 min. Correlation analyses of fluctuations in fluorescence reporter activity reveal that the fronts emerge from a pair of gene-expression waves of matrix production and sporulation. The localized expression waves travel across cells that are immobilized in the biofilm matrix in contrast to active cell migration or horizontal colony spreading. Our results suggest that front propagation arises via a local developmental program occurring at the level of individual bacterial cells, likely driven by nutrient depletion and metabolic by-product accumulation. A single-length scale and timescale couples the spatiotemporal propagation of both fronts throughout development. As a result, gene expression patterns within the advancing fronts collapse to self-similar expression profiles. Our findings highlight the key role of the localized cellular developmental program associated with the propagating front in describing biofilm growth. 相似文献
103.
In the past years, enantioanalysis became very important for clinical analysis; biomarkers/substances of biomedical importance with chiral structure should be analyzed and their presence correlated with the specific disorder. Therefore, we developed a method for the assay of l ‐ and d ‐glucose, based on molecular recognition of l ‐ and d ‐glucose. While for d ‐glucose there are many methods to assess its quantity, the l ‐enantiomer is not routinely detected by standard methods. Two stochastic microsensors based on the immobilization of Copper(II)phthalocyanine and Ni(II)phthalocyanine, in natural diamond powder, were proposed for the enantioanalysis of glucose. The proposed methods proved to have high sensitivities and were able to be used for determination of concentrations as low as 2.5 pg mL?1 for d ‐glucose and as low as 2.5 fg mL?1 for l ‐glucose. The enatioanalysis was performed with good results in whole blood samples collected from diabetic patients. 相似文献
104.
Ioana Cristina Constantinescu Gabriel Chi?amera D. Khlur B. Mukhim Costic? Adam 《ZooKeys》2016,(557):45-57
The article describes a new species of the feather mite family Pteronyssidae (Acarina: Psoroptidia) from the Gray Sibia Heterophasia
gracilis (McClelland) (Passeriformes, Leiothrichidae) in India (Meghalaya, Jaintia Hills, Shnongrim village). Males of Timalinyssus
wahlangi
sp. n. differ from those of all Timalinyssus species by having the horseshoe-shaped epiandrum with a short anterior extension. Females of the new species differ from those of all previously known species of the genus in having the hysteronotal shield with deep lateral incisions between e2 and f2 setae. A key to all species of the genus Timalinyssus is presented. 相似文献
105.
Vlad Al. Toma Anca D. Farca? Ioana Roman Bogdan Sevastre Denisa Hathazi Florina Scurtu Grigore Damian Radu Silaghi-Dumitrescu 《PloS one》2016,11(4)
A series of hemoglobin-based oxygen carrier candidates (HBOC), previously noted for their differences in prooxidative and physiological reactivity, were compared in terms of the negative effects displayed upon injection in Wistar rats. At the concentrations tested, antioxidant strategies based on albumin as well as based on rubrerythrin appear to offer observable physiological advantages. 相似文献
106.
How effective are cognitive behavior therapies for major depression and anxiety disorders? A meta‐analytic update of the evidence
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Pim Cuijpers Ioana A. Cristea Eirini Karyotaki Mirjam Reijnders Marcus J.H. Huibers 《World psychiatry》2016,15(3):245-258
We report the current best estimate of the effects of cognitive behavior therapy (CBT) in the treatment of major depression (MDD), generalized anxiety disorder (GAD), panic disorder (PAD) and social anxiety disorder (SAD), taking into account publication bias, the quality of trials, and the influence of waiting list control groups on the outcomes. In our meta‐analyses, we included randomized trials comparing CBT with a control condition (waiting list, care‐as‐usual or pill placebo) in the acute treatment of MDD, GAD, PAD or SAD, diagnosed on the basis of a structured interview. We found that the overall effects in the 144 included trials (184 comparisons) for all four disorders were large, ranging from g=0.75 for MDD to g=0.80 for GAD, g=0.81 for PAD, and g=0.88 for SAD. Publication bias mostly affected the outcomes of CBT in GAD (adjusted g=0.59) and MDD (adjusted g=0.65), but not those in PAD and SAD. Only 17.4% of the included trials were considered to be high‐quality, and this mostly affected the outcomes for PAD (g=0.61) and SAD (g=0.76). More than 80% of trials in anxiety disorders used waiting list control groups, and the few studies using other control groups pointed at much smaller effect sizes for CBT. We conclude that CBT is probably effective in the treatment of MDD, GAD, PAD and SAD; that the effects are large when the control condition is waiting list, but small to moderate when it is care‐as‐usual or pill placebo; and that, because of the small number of high‐quality trials, these effects are still uncertain and should be considered with caution. 相似文献
107.
Brandusa Elena Lixandru Ani Ioana Cotar Monica Straut Codruta Romanita Usein Dana Cristea Simona Ciontea Dorina Tatu-Chitoiu Irina Codita Alexandru Rafila Maria Nica Mariana Buzea Anda Baicus Mihaela Camelia Ghita Irina Nistor Cristina Tuchilu? Marina Indreas Felicia Antohe Corinna Glasner Hajo Grundmann Aftab Jasir Maria Damian 《PloS one》2015,10(11)
108.
Influence of the interleukin-6 -174 G/C gene polymorphism on exercise training-induced changes in glucose tolerance indexes. 总被引:2,自引:0,他引:2
Jennifer A McKenzie Edward P Weiss Ioana A Ghiu Onanong Kulaputana Dana A Phares Robert E Ferrell James M Hagberg 《Journal of applied physiology》2004,97(4):1338-1342
A polymorphism in the IL-6 gene, a G-to-C substitution 176 bp upstream of the ATG translation initiation site, has been associated with diabetes prevalence and insulin resistance. Interventions including exercise training are frequently used to modify cardiovascular disease risk factors. Consequently, this project examined associations between the IL-6 -174 genotype and oral glucose tolerance test outcomes in 50- to 75-yr-old sedentary men and postmenopausal women before and after aerobic exercise training. Among the 87 individuals who started the study, 56 were retested after 6 mo of aerobic exercise training. Subject characteristics at baseline did not differ between the IL-6 genotype groups with the exception of fasting glucose, which was higher (P = 0.02, covariates age, gender, and ethnicity) in the CC genotype group. The training-induced change in glucose area under the curve during the oral glucose tolerance test varied between the IL-6 -174 genotype groups (P = 0.05, covariates age, gender, ethnicity, baseline glucose area under the curve, and percent body fat change) with a significant decrease occurring only in the GG genotype group. Insulin outcomes did not differ among the groups at baseline or after training. Training-induced changes in weight, percent body fat, maximal oxygen consumption, fasting glucose, and an insulin sensitivity index also changed similarly among the genotype groups. In conclusion, fasting glucose and the extent to which glucose tolerance changes with exercise training may be influenced by the IL-6 -174 gene polymorphism. 相似文献
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