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811.
Mel Campbell Kevin Y. Kim Pei-Ching Chang Steve Huerta Bogdan Shevchenko Don-Hong Wang Chie Izumiya Hsing-Jien Kung Yoshihiro Izumiya 《Journal of virology》2014,88(3):1843-1848
Latent Kaposi''s sarcoma-associated herpesvirus (KSHV) episomes are coated with viral latency-associated nuclear antigen (LANA). In contrast, LANA rapidly disassociates from episomes during reactivation. Lytic KSHV expresses polyadenylated nuclear RNA (PAN RNA), a long noncoding RNA (lncRNA). We report that PAN RNA promotes LANA-episome disassociation through an interaction with LANA which facilitates LANA sequestration away from KSHV episomes during reactivation. These findings suggest that KSHV may have evolved an RNA aptamer to regulate latent protein function. 相似文献
812.
Yuriy Rebets Bogdan Tokovenko Igor Lushchyk Christian Rückert Nestor Zaburannyi Andreas Bechthold J?rn Kalinowski Andriy Luzhetskyy 《BMC genomics》2014,15(1)
Background
Kutzneria is a representative of a rarely observed genus of the family Pseudonocardiaceae. Kutzneria species were initially placed in the Streptosporangiaceae genus and later reconsidered to be an independent genus of the Pseudonocardiaceae. Kutzneria albida is one of the eight known members of the genus. This strain is a unique producer of the glycosylated polyole macrolide aculeximycin which is active against both bacteria and fungi. Kutzneria albida genome sequencing and analysis allow a deeper understanding of evolution of this genus of Pseudonocardiaceae, provide new insight in the phylogeny of the genus, as well as decipher the hidden secondary metabolic potential of these rare actinobacteria.Results
To explore the biosynthetic potential of Kutzneria albida to its full extent, the complete genome was sequenced. With a size of 9,874,926 bp, coding for 8,822 genes, it stands alongside other Pseudonocardiaceae with large circular genomes. Genome analysis revealed 46 gene clusters potentially encoding secondary metabolite biosynthesis pathways. Two large genomic islands were identified, containing regions most enriched with secondary metabolism gene clusters. Large parts of this secondary metabolism “clustome” are dedicated to siderophores production.Conclusions
Kutzneria albida is the first species of the genus Kutzneria with a completely sequenced genome. Genome sequencing allowed identifying the gene cluster responsible for the biosynthesis of aculeximycin, one of the largest known oligosaccharide-macrolide antibiotics. Moreover, the genome revealed 45 additional putative secondary metabolite gene clusters, suggesting a huge biosynthetic potential, which makes Kutzneria albida a very rich source of natural products. Comparison of the Kutzneria albida genome to genomes of other actinobacteria clearly shows its close relations with Pseudonocardiaceae in line with the taxonomic position of the genus.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-885) contains supplementary material, which is available to authorized users. 相似文献813.
Junfang Wu Bogdan A Stoica Tao Luo Boris Sabirzhanov Zaorui Zhao Kelsey Guanciale 《Cell cycle (Georgetown, Tex.)》2014,13(15):2446-2458
Cognitive dysfunction has been reported in patients with spinal cord injury (SCI), but it has been questioned whether such changes may reflect concurrent head injury, and the issue has not been addressed mechanistically or in a well-controlled experimental model. Our recent rodent studies examining SCI-induced hyperesthesia revealed neuroinflammatory changes not only in supratentorial pain-regulatory sites, but also in other brain regions, suggesting that additional brain functions may be impacted following SCI. Here we examined effects of isolated thoracic SCI in rats on cognition, brain inflammation, and neurodegeneration. We show for the first time that SCI causes widespread microglial activation in the brain, with increased expression of markers for activated microglia/macrophages, including translocator protein and chemokine ligand 21 (C–C motif). Stereological analysis demonstrated significant neuronal loss in the cortex, thalamus, and hippocampus. SCI caused chronic impairment in spatial, retention, contextual, and fear-related emotional memory—evidenced by poor performance in the Morris water maze, novel objective recognition, and passive avoidance tests. Based on our prior work implicating cell cycle activation (CCA) in chronic neuroinflammation after SCI or traumatic brain injury, we evaluated whether CCA contributed to the observed changes. Increased expression of cell cycle-related genes and proteins was found in hippocampus and cortex after SCI. Posttraumatic brain inflammation, neuronal loss, and cognitive changes were attenuated by systemic post-injury administration of a selective cyclin-dependent kinase inhibitor. These studies demonstrate that chronic brain neurodegeneration occurs after isolated SCI, likely related to sustained microglial activation mediated by cell cycle activation. 相似文献
814.
Ahmad Fawad Jebran Ulrike Schleicher Reto Steiner Pia Wentker Farouq Mahfuz Hans-Christian Stahl Faquir Mohammad Amin Christian Bogdan Kurt-Wilhelm Stahl 《PLoS neglected tropical diseases》2014,8(2)
Background
Anthroponotic cutaneous leishmaniasis (CL) due to Leishmania (L.) tropica infection is a chronic, frequently disfiguring skin disease with limited therapeutic options. In endemic countries healing of ulcerative lesions is often delayed by bacterial and/or fungal infections. Here, we studied a novel therapeutic concept to prevent superinfections, accelerate wound closure, and improve the cosmetic outcome of ACL.Methodology/Principal Findings
From 2004 to 2008 we performed a two-armed, randomized, double-blinded, phase IIa trial in Kabul, Afghanistan, with patients suffering from L. tropica CL. The skin lesions were treated with bipolar high-frequency electrocauterization (EC) followed by daily moist-wound-treatment (MWT) with polyacrylate hydrogel with (group I) or without (group II) pharmaceutical sodium chlorite (DAC N-055). Patients below age 5, with facial lesions, pregnancy, or serious comorbidities were excluded. The primary, photodocumented outcome was the time needed for complete lesion epithelialization. Biopsies for parasitological and (immuno)histopathological analyses were taken prior to EC (1st), after wound closure (2nd) and after 6 months (3rd). The mean duration for complete wound closure was short and indifferent in group I (59 patients, 43.1 d) and II (54 patients, 42 d; p = 0.83). In patients with Leishmania-positive 2nd biopsies DAC N-055 caused a more rapid wound epithelialization (37.2 d vs. 58.3 d; p = 0.08). Superinfections occurred in both groups at the same rate (8.8%). Except for one patient, reulcerations (10.2% in group I, 18.5% in group II; p = 0.158) were confined to cases with persistent high parasite loads after healing. In vitro, DAC N-055 showed a leishmanicidal effect on pro- and amastigotes.Conclusions/Significance
Compared to previous results with intralesional antimony injections, the EC plus MWT protocol led to more rapid wound closure. The tentatively lower rate of relapses and the acceleration of wound closure in a subgroup of patients with parasite persistence warrant future studies on the activity of DAC N-055.Trial Registration
ClinicalTrails.gov NCT00947362相似文献815.
Justyna Czech-Kowalska Julita Latka-Grot Dorota Bulsiewicz Maciej Jaworski Pawel Pludowski Grazyna Wygledowska Bogdan Chazan Beata Pawlus Anna Zochowska Maria K. Borszewska-Kornacka Elzbieta Karczmarewicz Edyta Czekuc-Kryskiewicz Anna Dobrzanska 《PloS one》2014,9(9)
Objective
The optimal vitamin D intake for nursing women is controversial. Deterioration, at least in bone mass, is reported during lactation. This study evaluated whether vitamin D supplementation during lactation enhances the maternal and infant’s vitamin D status, bone mass and body composition.Design and Methods
After term delivery, 174 healthy mothers were randomized to receive 1200 IU/d (800 IU/d+400 IU/d from multivitamins) or 400 IU/d (placebo+400 IU/d from multivitamins) of cholecalciferol for 6 months while breastfeeding. All infants received 400 IU/d of cholecalciferol. Serum 25-hydroxyvitamin D [25(OH)D], iPTH, calcium, urinary calcium, and densitometry were performed in mother-offspring pairs after delivery, and at 3 and 6 months later.Results
A total of 137 (79%) (n = 70; 1200 IU/d, n = 67; 400 IU/d) completed the study. 25(OH)D was similar in both groups at baseline (13.7 ng/ml vs. 16.1 ng/ml; P = 0.09) and at 3 months (25.7 ng/ml vs. 24.5 ng/ml; P = 0.09), but appeared higher in the 1200 IU/d group at 6 months of supplementation (25.6 ng/ml vs. 23.1 ng/ml; P = 0.009). The prevalence of 25(OH)D <20 ng/ml was comparable between groups at baseline (71% vs. 64%, P = 0.36) but lower in the 1200 IU/d group after 3 months (9% vs. 25%, P = 0.009) and 6 months (14% vs. 30%, P = 0.03). Maternal and infants’ iPTH, calciuria, bone mass and body composition as well as infants’ 25(OH)D levels were not significantly different between groups during the study. Significant negative correlations were noted between maternal 25(OH)D and fat mass (R = −0.49, P = 0.00001), android fat mass (R = −0.53, P = 0.00001), and gynoid fat mass (R = −0.43, P = 0.00001) after 6 months of supplementation.Conclusions
Vitamin D supplementation at a dose of 400 IU/d was not sufficient to maintain 25(OH)D >20 ng/ml in nursing women, while 1200 IU/d appeared more effective, but had no effect on breastfed offspring vitamin D status, or changes in the bone mass and the body composition observed in both during breastfeeding.Trial Registration
ClinicalTrials.gov NCT01506557相似文献816.
Helena Marti-Soler Semira Gonseth Cédric Gubelmann Silvia Stringhini Pascal Bovet Pau-Chung Chen Bogdan Wojtyniak Fred Paccaud Dai-Hua Tsai Tomasz Zdrojewski Pedro Marques-Vidal 《PloS one》2014,9(11)
Background
Cardiovascular diseases (CVD) mortality has been shown to follow a seasonal pattern. Several studies suggested several possible determinants of this pattern, including misclassification of causes of deaths. We aimed at assessing seasonality in overall, CVD, cancer and non-CVD/non-cancer mortality using data from 19 countries from different latitudes.Methods and Findings
Monthly mortality data were compiled from 19 countries, amounting to over 54 million deaths. We calculated ratios of the observed to the expected numbers of deaths in the absence of a seasonal pattern. Seasonal variation (peak to nadir difference) for overall and cause-specific (CVD, cancer or non-CVD/non-cancer) mortality was analyzed using the cosinor function model. Mortality from overall, CVD and non-CVD/non-cancer showed a consistent seasonal pattern. In both hemispheres, the number of deaths was higher than expected in winter. In countries close to the Equator the seasonal pattern was considerably lower for mortality from any cause. For CVD mortality, the peak to nadir differences ranged from 0.185 to 0.466 in the Northern Hemisphere, from 0.087 to 0.108 near the Equator, and from 0.219 to 0.409 in the Southern Hemisphere. For cancer mortality, the seasonal variation was nonexistent in most countries.Conclusions
In countries with seasonal variation, mortality from overall, CVD and non-CVD/non-cancer show a seasonal pattern with mortality being higher in winter than in summer. Conversely, cancer mortality shows no substantial seasonality. 相似文献817.
818.
Matthias Hammon Bernd Kunz Veronika Dinzl Ferdinand J. Kammerer Siegfried A. Schwab Christian Bogdan Michael Uder Philipp M. Schlechtweg 《PloS one》2014,9(9)
Background
To prove effectiveness of wrapping tablet computers in order to reduce microbiological contamination and to evaluate whether a plastic bag-covered tablet leads to impaired user satisfaction or touchscreen functionality.Materials and Methods
Within a period of 11 days 115 patients were provided with a tablet computer while waiting for their magnetic resonance imaging examination. Every day the contamination of the surface of the tablet was determined before the first and after the final use. Before the device was handed over to a patient, it was enclosed in a customized single-use plastic bag, which was analyzed for bacterial contamination after each use. A questionnaire was applied to determine whether the plastic bag impairs the user satisfaction and the functionality of the touchscreen.Results
Following the use by patients the outside of the plastic bags was found to be contaminated with various bacteria (657.5 ± 368.5 colony forming units/day); some of them were potentially pathogenic. In contrast, the plastic bag covered surface of the tablet was significantly less contaminated (1.7 ± 1.9 colony forming units/day). Likewise, unused plastic bags did not show any contamination. 11% of the patients reported problems with the functionality of the touchscreen. These patients admitted that they had never used a tablet or a smartphone before.Conclusions
Tablets get severely contaminated during usage in a clinical setting. Wrapping with a customized single-use plastic bag significantly reduces microbiological contamination of the device, protects patients from the acquisition of potentially pathogenic bacteria and hardly impairs the user satisfaction and the functionality of the touchscreen. 相似文献819.
Seid Muhie Dawud Karsten Raulund-Rasmussen Timo Domisch Leena Finér Bogdan Jaroszewicz Lars Vesterdal 《Ecosystems》2016,19(4):645-660
We explored tree species diversity effects on soil C stock, C/N ratio, and pH as compared with effects of tree species identity. We sampled forest floors and mineral soil (0–40 cm) in a diversity gradient of 1–5 tree species composed of conifers and broadleaves in Bia?owie?a Forest, Poland. Diversity was a weaker driver than identity of soil C stocks, C/N ratio, and pH in the soil profile. However, there were significant non-additive effects of diversity and significant effects of identity on C stock and C/N ratio within different parts of the soil profile. More diverse forests had higher C stocks and C/N ratios in the 20–40 cm layer, whereas identity in terms of conifer proportion increased C stocks and C/N ratios only in forest floors. A positive relationship between C stocks and root biomass in the 30–40 cm layer suggested that belowground niche complementarity could be a driving mechanism for higher root carbon input and in turn a deeper distribution of C in diverse forests. Diversity and identity affected soil pH in topsoil with positive and negative impacts, respectively. More diverse forests would lead to higher soil nutrient status as reflected by higher topsoil pH, but there was a slight negative effect on N status as indicated by higher C/N ratios in the deeper layers. We conclude that tree species diversity increases soil C stocks and nutrient status to some extent, but tree species identity is a stronger driver of the studied soil properties, particularly in the topsoil. 相似文献
820.
Cristian Capitanescu Anca Monica Macovei Oprescu Alexandru Supeanu Bogdan Ioan Coculescu Victor Strambu Radu Alexandru Macovei 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):1471-1475
The finding of the most appropriate way to assess precisely the antivenom efficacy represents one of the major issues for antivenom standardization and success increasing of antivenom therapy. The efficacy of experimental Vipera ammodytes antivenom raised in sheep was determined using in vivo mouse lethality test, respectively, L-aminoacid oxidase, total proteinase and phospholipase A2 antienzymatic effectiveness. The values gained for the antivenom potency depend on the method of measure. So, some of the most toxic venom proteins own phospholipase A2 activity and provide the highest antivenom potency (lowest effective dose) values by antienzymatic assay method. This value is similar with total antiproteolytic antivenom potency value, but almost three times higher than value obtained by L-aminoacid oxidase (low toxic viper venom protein) antienzymatic assay method. 相似文献