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21.
Michal Bijak Alicja Olejnik Bozena Rokita Agnieszka Morel Angela Dziedzic Elzbieta Miller Joanna Saluk‐Bijak 《Journal of cellular and molecular medicine》2019,23(5):3476-3482
Epidemiological studies indicate a high risk of stroke, heart failure and myocardial infarction in patients with multiple sclerosis, especially in its secondary progressive (SPMS) phase. Some ischaemic events are directly associated with abnormal platelet functions and their prothrombotic activity. Recent reports, including this study, confirm the increased activation of circulating platelets in SPMS, and also show increased platelet reactivity, among other responses, as well as strong aggregation. In this current study, we conducted a comparative analysis of the platelet proteome in SPMS patients and in healthy controls, to demonstrate the quantitative and qualitative differences likely to affect functional changes observed in SPMS. During densitometry evaluation of 2‐D fluorescence difference gel electrophoresis, we observed differences between the electrophoretic patterns of SPMS platelets and the control samples. To determine a detailed characterisation of the proteome changes in the SPMS patients’ blood platelets, in the next stage, we performed mass spectrometry of selected spots and indicated the increased presence of four proteins (fibrinogen, α‐2 macroglobulin, septin‐14 and tubulin β‐1 chain). The most important of these is the increased amount of prothrombotic protein, fibrinogen, which seems to confirm the accuracy of the imaging and potentially explains the increased risk of platelet‐origin thrombotic events. This study provides new knowledge of the potential existence of the molecular mechanisms responsible for the acceleration of the platelet pro‐coagulant function in SPMS. This can help to identify new targets for therapy, which can then be used not only in the second stage of the disease. 相似文献
22.
Barbara Hulanicka Anna Lipowicz Sawomir Kozie Alicja Kowalisko 《Economics & Human Biology》2007,5(1):48-60
The objective of this paper is to evaluate: (a) the association between BMI in childhood and adolescence and BMI at age 50, and (b) the association between timing of maturation at puberty and BMI at age 50 and the occurrence of high blood pressure. We explore whether differences in somatic and physiological factors observed among children with early or late onset of puberty indicates that this period of life could be critical for appearance of some CVD risk factors later in the life cycle. Our data include 135 males and 148 females, born in 1953, participants in the Wroc?aw Longitudinal Study. Data pertaining to their growth and several indices of sexual and skeletal maturation were collected yearly between age 8 and 18. Subsequently, their anthropometric traits were measured and cardiovascular health status was assessed at age 50. We find that BMI at distinct stages in the life cycle were positively correlated. Also BMI at 50 were positively associated with blood pressure at 50. Moreover, earlier maturation at puberty is associated with higher values of BMI at age 50. We also find that earlier pubertal maturation is an independent factor that influences the appearance of high blood pressure in adulthood. 相似文献
23.
Boroń A 《Genetica》1999,105(3):293-300
The present work provides new data on the banding pattern of diploid Cobitis taenia and its triploid hybrid females, which belong to the diploid–polyploid complex in the Vistula River tributary. C-banding,
silver-staining (Ag), and fluorescent staining with chromomycin A3 techniques were used to describe the diploid and triploid karyotype. The karyotype of Cobitis taenia of 2n=48 was characterised by one pair of NOR-bearing subtelocentric chromosomes and at least four chromosomes with CMA3-positive sites. The C-positive heterochromatin was present in the centromeres of almost all chromosomes and the pericentromeric
regions of several metacentric and submetacentric chromosomes.
The triploid females of 3n=74 had two pairs of chromosomes with active NORs. The NORs-sites were located terminally on two biarmed and two uniarmed
chromosomes. The CMA3-staining revealed at least six A3-positive sites. The C-banded and A3-stained triploid karyotype was composed of haploid set of Cobitis taenia and diploid set of unidentified species, so heterochromatin pattern confirmed the possibility of their hybrid origin. The
characteristics of banded diploid and triploid karyotype, and the hypothetical karyotype of an unknown species of 2n=50 is discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
24.
Danuta Stępalska Krystyna Harmata Idalia Kasprzyk Dorota Myszkowska Alicja Stach 《Aerobiologia》1999,15(1):39-47
The concentration of airborne spores of Cladosporium and Alternaria has been investigated at five monitoring stations situated in cities from the foot of the Tatra Mountains to central Poland along a south-north transect (Zakopane, Kraków, Ostrowiec witokrzyski, Warszawa, Pozna) i.e. from a height of 900 m to 80 m above sea level. The aerobiological monitoring of fungal spores was performed by means of five Burkard volumetric spore traps.Cladosporium spores were dominant at all the stations. The highest Cladosporium and Alternaria spore concentrations were observed at all the sites in July and August, except at Warszawa in both years and at Pozna in 1995 where the maximum of Cladosporium spores occurred in June and July, and at Ostrowiec witokrzyski in 1995 where the maximum was found in July, August and September.Fungal spore concentrations in Zakopane and Kraków were significantly lower than those in Ostrowiec witokrzyski, Warszawa and Pozna and periods of abundant Cladosporium spore occurrence were different in these two groups of monitoring stations. 相似文献
25.
We examined Ixodes ricinus embryos between 18 and 28 days of development with light, scanning and transmission electron microscopy. The differences in inner structure attested to establish three successive developmental stages: days 18-20, day 23, and days 26-28. Between 18 and 20 days the embryos are at early stages of organogenesis. Salivary glands cannot be identified at that stage. In 23-day-old embryos salivary glands are already outlined but the structure of alveoles is still different from that in larvae in which the embryonic development has been completed. Gland cells start to form alveoles and become active between 26 and 28 days of the development. 相似文献
26.
The highly evolutionarily conserved serotonin transporter (SERT) regulates the entire serotoninergic system and its receptors via modulation of extracellular fluid serotonin concentrations. Differences in SERT expression and function produced by three SERT genes and their variants show associations with multiple human disorders. Screens of DNA from patients with autism, ADHD, bipolar disorder, and Tourette's syndrome have detected signals in the chromosome 17q region where SERT is located. Parallel investigations of SERT knockout mice have uncovered multiple phenotypes that identify SERT as a candidate gene for additional human disorders ranging from irritable bowel syndrome to obesity. Replicated studies have demonstrated that the SERT 5'-flanking region polymorphism SS genotype is associated with poorer therapeutic responses and more frequent serious side effects during treatment with antidepressant SERT antagonists, namely, the serotonin reuptake inhibitors (SRIs). 相似文献
27.
Qualitative and quantitative composition of pigments in Phaeodactylum tricornutum (Bacillariophyceae) stressed by iron 总被引:1,自引:0,他引:1
The effect of Fe(III) deficiency on qualitative and quantitative changes in pigment composition in Phaeodactylum tricornutum Bohlin was demonstrated by HPLC and AAS. Maximum content of pigments showed the diatom cells incubated at the optimum iron concentration, i.e., 10 M. The contents of chlorophyll a, chlorophyll c
1+c
2, fucoxanthin, diadinoxanthin and ,-carotene were 109.99, 20.16, 40.39, 1.29 and 1.48 fg per cell, respectively. The results obtained showed that Fe(III) affected qualitative and quantitative pigment composition in P. tricornutum. The content of individual pigments, proportions between accompanying pigments and their ratios to chlorophyll a were important indicators of phytoplankton response to iron stress. The strong reduction in ,-carotene content, several times (2–5) increase in diadinoxanthin level as compared to ,-carotene, and high amount of diadinoxanthin in relation to chlorophyll a were observed in algae growing at very low Fe(III) concentrations, 0.001 and 0.01 M. The data suggested that phytoplankton pigments could be a potential physiological marker. 相似文献
28.
29.
Eleven strains of Escherichia coli were isolated from 54 bank voles living in the LomZa Landscape Park of the Narew River Valley, indicating that E. coli is not common in the alimentary tract of these mammals. On the basis of pulsed-field gel electrophoresis and computer-assisted analysis, the isolates were grouped into six genotypes at similarities of 39%. Chromosome length of E. coli under study differed by as much as 900 kb, ranging 2.7-3.6 Mb. All strains were susceptible to amikacin and ciprofloxacin, whereas, for tetracycline, streptomycin, ampicillin, and cefonicid, different results were noted. No differences were detected among the plasmid complements of eight strains (73%), for which plasmid profiles revealed the presence of two plasmidic bands. One, three and four plasmids were observed in a plasmid pattern of single isolates. The observation from the study indicated the high genetic polymorphism among the isolates recovered from the animals of one species living in the same environment. 相似文献
30.
Pettus BJ Bielawska A Spiegel S Roddy P Hannun YA Chalfant CE 《The Journal of biological chemistry》2003,278(40):38206-38213
Despite the importance of prostaglandins, little is known about the regulation of prostanoid synthesis proximal to the activation of cytosolic phospholipase A2, the initial rate-limiting step. In this study, ceramide-1-phosphate (C-1-P) was shown to be a specific and potent inducer of arachidonic acid (AA) and prostanoid synthesis in cells. This study also demonstrates that two well established activators of AA release and prostanoid synthesis, the cytokine, interleukin-1beta (IL-1beta), and the calcium ionophore, A23187, induce an increase in C-1-P levels within the relevant time-frame of AA release. Furthermore, the enzyme responsible for the production of C-1-P in mammalian cells, ceramide kinase, was activated in response to IL-1beta and A23187. RNA interference targeted to ceramide kinase specifically down-regulated ceramide kinase mRNA and activity with a concomitant decrease of AA release in response to IL-1beta and A23187. Down-regulation of ceramide kinase had no effect on AA release induced by exogenous C-1-P. Collectively, these results indicate that ceramide kinase, via the formation of C-1-P, is an upstream modulator of phospholipase A2 activation. This study identifies previously unknown roles for ceramide kinase and its product, C-1-P, in AA release and production of eicosanoids and provides clues for potential new targets to block inflammatory responses. 相似文献