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691.
Elżbieta Bonda-Ostaszewska Tadeusz Włostowski Alicja Krasowska Paweł Kozłowski 《Acta theriologica》2012,57(4):289-294
Seasonal changes in lipid droplet size and lipid peroxidation in the brown adipose tissue (BAT) of wild bank voles were examined. In addition, a role of photoperiod in these changes was studied; bank voles were held from the birth under long photoperiod (LP) for 12 weeks, and then half of them was transferred to short photoperiod (SP) for 6 weeks and another one remained under LP. In the wild bank voles the absolute BAT weight was seasonally constant, while the significant differences in the lipid droplet size were observed. The smallest lipid droplets (mean, 11 μm2) were seen in winter; they increased by 30 % in spring and reached the highest size (24 μm2) in summer. Lipid peroxidation in the BAT did not differ significantly between the seasons, although high intraseason variation of this process was noted. The laboratory experiment revealed that the size of lipid droplets was determined by photoperiod; SP induced 13-fold decrease, and continuous exposure to LP brought about a further 2.5-fold increase in the size of lipid droplets. Conversely, a significant decrease in lipid peroxidation was seen in LP bank voles in comparison with the SP animals. The data indicate that short photoperiod is responsible for the small size of lipid droplets in the BAT of bank voles during winter, which may be a necessary requirement for high thermogenic capacity of the tissue. Photoperiod appears also to affect lipid peroxidation in the BAT of these animals. 相似文献
692.
F. Javier Rodríguez-Rajo Diego Fdez-Sevilla Alicja Stach Victoria Jato 《Aerobiologia》2010,26(1):1-14
Pollen data recorded by a single sampler in any given city often fail to reflect particular events occurring in surrounding
areas. This is frequently overlooked when interpreting aerobiological results, and therefore pollen data obtained in urban
areas may not necessarily be representative of the situation in more rural areas of the same city. Our purpose is to assess
differences between allergenic pollen concentrations recorded in an urban area (Eskulap) and a rural/suburban (Morasko) of
the same city from 2005 to 2007. Anova-Manova Scheffe, Spearman correlation and Mixed-design ANOVA whitin-subjects effects
tests were applied. The results obtained have showed longer pollen seasons, earlier starts of flowering and later conclusion
in the urban area. The participation of arboreal pollen in the pollen fall of both sites had enough significative similarities
to determine that is linked to regional conditions, while differences in the atmospheric pollen content of herbaceous plants
between sites should be due to local conditions. 相似文献
693.
Paulina Paluchowska Marianna Tokarczyk Bozena Bogusz Iwona Skiba Alicja Budak 《Memórias do Instituto Oswaldo Cruz》2014,109(4):436-441
Over the last decades, Candida spp have been responsible for an
increasing number of infections, especially in patients requiring intensive care.
Knowledge of local epidemiology and analysis of the spread of these pathogens is
important in understanding and controlling their transmission. The aim of this study
was to evaluate the genetic diversity of 31 Candida albicans and
17 Candida glabrata isolates recovered from intensive care unit
patients from the tertiary hospital in Krakow between 2011-2012. The strains were
typed by random amplified polymorphic DNA (RAPD) polymerase chain reaction using five
primers (CD16AS, HP1247, ERIC-2, OPE-3 and OPE-18). The results of the present
investigation revealed a high degree of genetic diversity among the isolates. No
clonal relationship was found among the C. albicans strains, whereas
two C. glabrata isolates were identical. The source of
Candida infection appeared to be mostly endogenous; however, the presence
of two clonal C. glabrata strains suggested the possibility of
cross-transmission of these pathogens. Our study confirmed the high discriminatory
power of the RAPD technique in the molecular typing of Candida
clinical isolates. This method may be applied to the evaluation of transmission
routes of pathogenic fungi on a local level. 相似文献
694.
Tim Gruber Chenchen Pan Raian E. Contreras Tobias Wiedemann Donald A. Morgan Alicja A. Skowronski Sandrine Lefort Cahuê De Bernardis Murat Ophelia Le Thuc Beata Legutko Francisco J. Ruiz-Ojeda María de la Fuente-Fernández Angel Luis García-Villalón Daniel González-Hedström Melanie Huber Klara Szigeti-Buck Timo D. Müller Siegfried Ussar Cristina García-Cáceres 《Cell metabolism》2021,33(6):1155-1170.e10
695.
Observation of Electrochemically Driven Elemental Segregation in a Si Alloy Thin‐Film Anode and its Effects on Cyclic Stability for Li‐Ion Batteries 下载免费PDF全文
Minsub Oh Sekwon Na Chang‐Su Woo Jun‐Ho Jeong Sung‐Soo Kim Alicja Bachmatiuk Mark Hermann Rümmeli Seungmin Hyun Hoo‐Jeong Lee 《Liver Transplantation》2015,5(22)
The results of employing (Ti, Fe)‐alloyed Si thin‐film anode for Li‐ion batteries are reported. The material demonstrates an impressive cyclic stability with stable operation for more than 500 cycles at a capacity higher than 1400 mAh g?1. Materials characterization using scanning electron microscopy and transmission electron microscopy illuminates an intriguing materials process behind the performance: ripple‐like pattern formation via electrochemically driven segregation of the inactive elements (Ti and Fe). The ripple structure plays a buffer role by suppressing loss of the active material upon further cycling, allowing the anode to gradually transform into an array of microbumps. The morphological evolution helps the anode endure long cycles (even up to 1000 cycles) without catastrophic failure as the bumps shrank slowly and steadily, consistent with the electrochemical data. 相似文献
696.
Symplasmic short- and long-distance communication may be regulated at different levels of plant body organization. It depends on cell-to-cell transport modulated by plasmodesmata conductivity and frequency but above all on morphogenetic fields that integrate a plant at the supracellular level. Their control of physiological and developmental processes is especially important in trees, where the continuum consists of 3-dimensional systems of: 1) stem cells in cambium, and 2) living parenchyma cells in the secondary conductive tissues. We found that long-distance symplasmic transport in trees is spatially regulated. Uneven distribution of fluorescent tracer in cambial cells along the branches examined illustrates an unknown intrinsic phenomenon that can possibly be important for plant organism integration. Here we illustrate the spatial dynamics of symplasmic transport in cambium, test and exclude the role of callose in its regulation, and discuss the mechanism that could possibly be responsible for the maintenance of this spatial pattern. 相似文献
697.
The effect of exogenously applied natural [indole-3-acetic acid (IAA), phenylacetic acid (PAA), indole-3-butyric acid (IBA)] and synthetic [1-naphthaleneacetic acid (NAA)] auxins on the growth and metabolism of green microalga Chlorella vulgaris was examined. Exogenous auxins acted in a concentration-dependent manner on algal growth. Phytohormones at concentration of 100 μM inhibited algal growth expressed as the number of cells. IAA and IBA displayed the highest biological activity at 0.1 μM, whereas PAA and NAA were characterized by the greatest stimulatory effect on the number of cells at 1 μM. Treatment with IAA and IBA at 0.1 μM or NAA and PAA at 1 μM increased the concentration of photosynthetic pigments, monosaccharides and soluble proteins in C. vulgaris. Moreover, all auxins stimulated enzymatic (ascorbate peroxidase, catalase, superoxide dismutase) and non-enzymatic antioxidant (ascorbate, glutathione) systems in C. vulgaris, and therefore, suppressed lipid peroxidation and hydrogen peroxide accumulation. The data supports the hypothesis that auxins play a central role in the regulation of C. vulgaris growth and metabolism and the components of cellular redox systems that are thought to have a prominent role in the regulation of auxin-dependent processes. 相似文献
698.
Alicja Puchta Avee Naidoo Chris P. Verschoor Dessi Loukov Netusha Thevaranjan Talveer S. Mandur Phuong-son Nguyen Manel Jordana Mark Loeb Zhou Xing Lester Kobzik Maggie J. Larché Dawn M. E. Bowdish 《PLoS pathogens》2016,12(1)
Monocyte phenotype and output changes with age, but why this occurs and how it impacts anti-bacterial immunity are not clear. We found that, in both humans and mice, circulating monocyte phenotype and function was altered with age due to increasing levels of TNF in the circulation that occur as part of the aging process. Ly6C+ monocytes from old (18–22 mo) mice and CD14+CD16+ intermediate/inflammatory monocytes from older adults also contributed to this “age-associated inflammation” as they produced more of the inflammatory cytokines IL6 and TNF in the steady state and when stimulated with bacterial products. Using an aged mouse model of pneumococcal colonization we found that chronic exposure to TNF with age altered the maturity of circulating monocytes, as measured by F4/80 expression, and this decrease in monocyte maturation was directly linked to susceptibility to infection. Ly6C+ monocytes from old mice had higher levels of CCR2 expression, which promoted premature egress from the bone marrow when challenged with Streptococcus pneumoniae. Although Ly6C+ monocyte recruitment and TNF levels in the blood and nasopharnyx were higher in old mice during S. pneumoniae colonization, bacterial clearance was impaired. Counterintuitively, elevated TNF and excessive monocyte recruitment in old mice contributed to impaired anti-pneumococcal immunity since bacterial clearance was improved upon pharmacological reduction of TNF or Ly6C+ monocytes, which were the major producers of TNF. Thus, with age TNF impairs inflammatory monocyte development, function and promotes premature egress, which contribute to systemic inflammation and is ultimately detrimental to anti-pneumococcal immunity. 相似文献
699.
700.