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51.
Jarek Wosik Wei Chen Kuang Qin Rafik M. Ghobrial Jacek Z. Kubiak Malgorzata Kloc 《Biophysical journal》2018,114(8):2001-2013
Macrophages play a crucial role in homeostasis, regeneration, and innate and adaptive immune responses. Functionally different macrophages have different shapes and molecular phenotypes that depend on the actin cytoskeleton, which is regulated by the small GTPase RhoA. The naive M0 macrophages are slightly elongated, proinflammatory M1 are round, and M2 antiinflammatory macrophages are elongated. We have recently shown in the rodent model system that genetic or pharmacologic interference with the RhoA pathway deregulates the macrophage actin cytoskeleton, causes extreme macrophage elongation, and prevents macrophage migration. Here, we report that an exposure of macrophages to a nonuniform magnetic field causes extreme elongation of macrophages and has a profound effect on their molecular components and organelles. Using immunostaining and Western blotting, we observed that magnetic force rearranges the macrophage actin cytoskeleton, the Golgi complex, and the cation channel receptor TRPM2, and modifies the expression of macrophage molecular markers. We have found that the magnetic-field-induced alterations are very similar to changes caused by RhoA interference. We also analyzed magnetic-field-induced forces acting on macrophages and found that the location and alignment of magnetic-field-elongated macrophages correlate very well with the simulated distribution and orientation of such magnetic force lines. 相似文献
52.
Katarzyna Kubiak Hanna Sielawa Janina Dziekońska-Rynko Dariusz Kubiak Martyna Rydzewska Ewa Dzika 《Experimental & applied acarology》2018,75(3):289-298
Dermacentor reticulatus is the second most important tick species in Poland. Although the north-eastern region of Poland is considered typical for D. reticulatus and is treated as a contiguous area of Eastern populations of the meadow ticks, the occurrence of this tick species in this region to date has been recorded as separate foci. The present report supplements data on the geographical distribution of D. reticulatus in urban and natural biotopes of north-eastern Poland (Warmia and Mazury province). In 2015–2017 (during the springtime activity of ticks) adult questing D. reticulatus were found in 13 of 25 monitored localities. Six sites are located in urbanized areas, within the administrative borders of the city of Olsztyn and seven sites are in natural biotopes in the central part of Warmia and Mazury. A total of 398 adult D. reticulatus ticks, including 257 females and 141 males, were collected. A comparison of data grouped according to urban and natural type of area revealed no statistical differences between them. Taking into account the habitat type, the mean tick density was the highest in open landscapes. The identification of new foci D. reticulatus in the endemic areas of Lyme borreliosis, tick-borne encephalitis and canine babesiosis is crucial for determining the risk of diseases transmitted by ticks and taking proper preventive measures. 相似文献
53.
Sixty mares in transition from winter anestrus to normal cyclicity were assigned to a 3 x 2 factorial experiment to determine the effect of energy intake and percentage of body fat on the interval to first ovulation. The factors were 1) percentage of body fat--thin (<11.5), good (11.5 to 15), or fat (>15); and 2) energy intake--maintenance (100% of National Research Council (NRC) digestible energy requirement for maintenance) or high energy (150% of NRC digestible energy requirement for maintenance). Percentage of body fat was estimated by ultrasonographic scanning of rump fat thickness. Energy treatments began on April 2 and ended on June 4. Mares were teased daily with a stallion and their ovaries were palpated per rectum daily or every third day. A high energy intake was effective in hastening ovulation for mares in the thin group (P < 0.05) but not for mares in the moderate or fat groups. Mares in the fat group had a shorter (P < 0.05) interval from April 2 to ovulation (26.4 +/- 4.2 d) than those in the good or high energy-thin groups (48.7 +/- 2.8 and 49.1 +/- 4.2 d, respectively). Duration of the initial estrus was shorter (P < 0.05) for mares in the fat group (16.2 +/- 5.7 d) compared with mares in the good group (34.7 +/- 3.9 d) and tended (P<0.12) to be shorter than mares in the high energy-thin group (29.0 +/- 5.7 d). 相似文献
54.
Daniel Galiano Bruno B. Kubiak Gerhard E. Overbeck Thales R. O. de Freitas 《Acta theriologica》2014,59(4):583-587
We analyzed the effects of tuco-tucos (Ctenomys minutus, Ctenomyidae) on plant cover, plant biomass, soil hardness, soil pH, and variables related to nutrient disposition (P, K, Mg, and Ca), using data from three areas in the South Brazilian coastal plain. In each area, samples were taken from sites with and without C. minutus and results are presented in a concatenate way. Our results show that the presence of C. minutus modifies total plant biomass, grass cover, bare soil, soil hardness, soil pH, and nutrient content. Soils horizons at the depths of 10 and 20 cm are significantly softer in sites with C. minutus and phosphorus and potassium had higher concentrations. The content of magnesium and calcium were not affected. Soil pH was significantly lower where tuco-tucos occurred. Altogether, our results show that these animals may have a significant effect on vegetation composition and dynamics as well as on soil properties. 相似文献
55.
Agnieszka Ludwikow ;Agata Ciesla ;Anna Kasprowicz-Malusk ;Filip Mitula ;Malgorzata Tajdel ;lukasz Gaigarnski ;Piotr A. Ziolkowski ;Piotr Kubiak ;Arleta Malecka ;Aneta Piechalak ;Marta Szabat ;Alicja Gorska ;Maciej Dabrowskia ;Izabela Ibragimow ;Jan Sadowski 《植物生理与分子生物学学报》2014,(6):960-976
Ethylene plays a crucial role in various biological processes and therefore its biosynthesis is strictly regu- lated by multiple mechanisms. Posttranslational regulation, which is pivotal in controlling ethylene biosynthesis, impacts 1-aminocyclopropane 1-carboxylate synthase (ACS) protein stability via the complex interplay of specific factors. Here, we show that the Arabidopsis thaliana protein phosphatase type 2C, ABI1, a negative regulator of abscisic acid signaling, is involved in the regulation of ethylene biosynthesis under oxidative stress conditions. We found that ABI1 interacts with ACS6 and dephosphorylates its C-terminal fragment, a target of the stress-responsive mitogen-activated protein kinase, MPK6. In addition, ABI1 controls MPK6 activity directly and by this means also affects the ACS6 phosphorylation level. Consistently with this, ozone-induced ethylene production was significantly higher in an ABI1 knockout strain (abiltd) than in wild-type plants. Importantly, an increase in stress-induced ethylene production in the abiltd mutant was compen- sated by a higher ascorbate redox state and elevated antioxidant activities. Overall, the results of this study provide evi- dence that ABI1 restricts ethylene synthesis by affecting the activity of ACS6. The ABI1 contribution to stress phenotype underpins its role in the interplay between the abscisic acid (ABA) and ethylene signaling pathways. 相似文献
56.
We compared the profile of histone H1 kinase activity, reflecting Maturation Promoting Factor (MPF) activity in oocytes bisected at the germinal vesicle (GV) stage and allowed to mature as separate oocyte halves in vitro. Whereas the oocyte halves containing the nucleus exhibited the same profile of increased kinase activity as that typical for intact oocytes, the anuclear halves revealed strong inhibition of the increase in this activity soon after germinal vesicle breakdown (GVBD). In contrast, the profile of MAP kinase activity did not differ significantly between anuclear and nucleus-containing oocyte halves throughout maturation. Of the two MPF components, CDK1 and cyclin B1, the amount of the latter was significantly reduced in anuclear halves, a reduction due to low-level synthesis and not to enhanced degradation. Expression of three reporter luciferase RNAs constructed, respectively, to contain cyclin B1-specific 3'UTR, the globin-specific 3'UTR, or no 3'UTR sequence was enhanced in nuclear halves, with significantly greater enhancement for the construct containing cyclin B1-specific 3'UTR as compared to the two other RNAs. We conclude that the profile of activity of MPF during mouse oocyte maturation is controlled by an unknown GV-associated factor(s) acting via 3'UTR-dependent control of cyclin B1 synthesis. These results require the revision of the hitherto prevailing view that the control of MPF activity during mouse oocyte maturation is independent of GV-derived material. 相似文献
57.
Łach A Grzybek M Heger E Korycka J Wolny M Kubiak J Kolondra A Bogusławska DM Augoff K Majkowski M Podkalicka J Kaczor J Stefanko A Kuliczkowski K Sikorski AF 《The Journal of biological chemistry》2012,287(23):18974-18984
S-Acylation of proteins is a ubiquitous post-translational modification and a common signal for membrane association. The major palmitoylated protein in erythrocytes is MPP1, a member of the MAGUK family and an important component of the ternary complex that attaches the spectrin-based skeleton to the plasma membrane. Here we show that DHHC17 is the only acyltransferase present in red blood cells (RBC). Moreover, we give evidence that protein palmitoylation is essential for membrane organization and is crucial for proper RBC morphology, and that the effect is specific for MPP1. Our observations are based on the clinical cases of two related patients whose RBC had no palmitoylation activity, caused by a lack of DHHC17 in the membrane, which resulted in a strong decrease of the amount of detergent-resistant membrane (DRM) material. We confirmed that this loss of detergent-resistant membrane was due to the lack of palmitoylation by treatment of healthy RBC with 2-bromopalmitic acid (2-BrP, common palmitoylation inhibitor). Concomitantly, fluorescence lifetime imaging microscopy (FLIM) analyses of an order-sensing dye revealed a reduction of membrane order after chemical inhibition of palmitoylation in erythrocytes. These data point to a pathophysiological relationship between the loss of MPP1-directed palmitoylation activity and perturbed lateral membrane organization. 相似文献
58.
The Spindle Assembly Checkpoint (SAC) inhibits anaphase until microtubule-to-kinetochore attachments are formed, thus securing correct chromosome separation and preventing aneuploidy. Whereas in mitosis even a single unattached chromosome keeps the SAC active, the high incidence of aneuploidy related to maternal meiotic errors raises a concern about the lower efficiency of SAC in oocytes. Recently it was suggested that in mouse oocytes, contrary to somatic cells, not a single chromosome but a critical mass of chromosomes triggers efficient SAC pointing to the necessity of evaluating the robustness of SAC in oocytes. Two types of errors in chromosome segregation upon meiosis I related to SAC were envisaged: (1) SAC escape, when kinetochores emit SAC-activating signal unable to stop anaphase I; and (2) SAC deceive, when kinetochores do not emit the signal. Using micromanipulations and live imaging of the first polar body extrusion, as well as the dynamics of cyclin B1 degradation, here we show that in mouse oocytes a single bivalent keeps the SAC active. This is the first direct evaluation of SAC efficiency in mouse oocytes, which provides strong evidence that the robustness of SAC in mammalian oocytes is comparable to other cell types. Our data do not contradict the hypothesis of the critical mass of chromosomes necessary for SAC activation, but suggest that the same rule may govern SAC activity also in other cell types. We postulate that the innate susceptibility of oocytes to errors in chromosome segregation during the first meiotic division may not be caused by lower efficiency of SAC itself, but could be linked to high critical chromosome mass necessary to keep SAC active in oocyte of large size. 相似文献
59.
The "Swine flu" pandemic of 2009 caused world-wide infections and deaths. Early efforts to understand its rate of spread were used to predict the probable future number of cases, but by the end of 2009 it was clear that these predictions had substantially overestimated the pandemic's eventual impact. In England, the Health Protection Agency made announcements of the number of cases of disease, which turned out to be surprisingly low for an influenza pandemic. The agency also carried out a serological survey half-way through the English epidemic. In this study, we use a mathematical model to reconcile early estimates of the rate of spread of infection, weekly data on the number of cases in the 2009 epidemic in England and the serological status of the English population at the end of the first pandemic wave. Our results reveal that if there are around 19 infections (i.e., seroconverters) for every reported case then the three data-sets are entirely consistent with each other. We go on to discuss when in the epidemic such a high ratio of seroconverters to cases of disease might have been detected, either through patterns in the case reports or through even earlier serological surveys. 相似文献
60.
Comparison of the (CCG)4-based PCR and MIRU-VNTR for molecular typing of Mycobacterium avium strains
Wojtasik A Kubiak AB Krzyżanowska A Majchrzak M Augustynowicz-Kopeć E Parniewski P 《Molecular biology reports》2012,39(7):7681-7686
Mycobacterium avium, a member of the group of non-tuberculous mycobacteria, is most often responsible for the serious diseases in humans and is frequently isolated from NTM-caused pulmonary events. In this connection the epidemiological aspect is also of great importance. Here we present a useful genetic assay that uses (CCG)(4)-based PCR for genotyping M. avium. After applying this test to 33 strains of M. avium, we found a discriminatory index of 0.979. The accuracy of this analysis was supported by a reasonable reproducibility of 95.1%. These results were compared with the Mycobacterial Intergenic Repeat Unit-Variable Number Tandem Repeats (MIRU-VNTR) typing scheme which had slightly lower discriminatory index of 0.945 however, the method was able to cluster different strains compared to CCG-PCR. Taking into account high discriminatory index and reproducibility, this test scheme has the potential as a screening tool in the investigation of M. avium infections, especially if combined with MIRU-VNTR. 相似文献