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121.
Witold Zurkowski 《Molecular & general genetics : MGG》1981,181(4):522-524
Summary When the nodulating Rhizobium trifolii strain 24Vior containing plasmid RP4 was conjugated with the non-nodulating R. trifolii mutant strain 24StrrNod-35, plasmid RP4 was transferred at a frequency 10-3–10-4. Two out of nearly three thousand tested transconjugants which contained plasmid RP4 had acquired the ability to form nodules on clovers. Molecular studies of the DNA of both these nodulating transconjugants showed the presence of plasmid RP4 and another plasmid which was not found in the original recipient strain. The size of this second plasmid corresponded to that of the plasmid pWZ2, the elimination of which was correlated with irreversible loss of the nodulating ability of R. trifolii strain 24 (Zurkowski and Lorkiewicz 1979). Plasmid RP4 was eliminated from cells by ethidium bromide, without the loss of nodulating properties. The nodulation capacity, however, was eliminated from transconjugants after incubation of bacteria at elevated temperature. Non-nodulating clones obtained after such incubation did not contain the plasmid pWZ2. The results indicate that the plasmid pWZ2 is a necessary element for induction of nodules by R. trifolii, and that it can be mobilized by plasmid RP4. 相似文献
122.
Plasmonics - Plasmons are fundamental collective excitations in many particle charged systems like in free electron liquid in metals, high energy nuclear plasma in solar core or in fusion devices,... 相似文献
123.
124.
Lucyna Mastalerz Magdalena Celińska-L?wenhoff Piotr Krawiec Bogdan Batko Witold T?ustochowicz Anetta Undas 《PloS one》2015,10(11)
Objectives
Given reports on the increased prevalence of thromboembolic incidents in patients with eosinophilic granulomatosis with polyangiitis (EGPA; Churg-Strauss syndrome), we investigated whether fibrin clot properties are unfavorably altered in EGPA.Methods
Ex vivo plasma fibrin clot characteristics, including clot permeability, turbidimetry and efficiency of fibrinolysis using two assays, were investigated in 34 consecutive patients with remission in EGPA according to the Birmingham Vasculitis Activity Score version 3 (23 female, 11 male), aged 48 (range, 21–80) years. The control group comprised 34 age- and sex- matched volunteers.Results
Compared with controls, patients with EGPA were characterized by denser fiber clots (estimated pore size, Ks, 7.30±0.93 vs 10.14±1.07 10−9 cm2), faster fibrin polymerization (lag phase in a turbidimetric curve, 41.8±3.6 vs 47.4±2.9 s), thicker fibrin fibers (maximum absorbance, ΔAbs, 0.87±0.09 vs 0.72±0.07), higher maximum levels of D-dimer released from clots (DDmax 4.10±0.46 vs 3.54±0.35 mg/L), and prolonged clot lysis time (t50%; 9.50±1.45 vs 7.56±0.87 min); all p<0.0001. Scanning electron microscopy images confirmed denser plasma fibrin networks composed of thinner fibers formed in EGPA. Antineutrophil cytoplasmic antibody status and C-reactive protein did not affect clot variables. Multivariate analysis adjusted for fibrinogen showed that Ks was predicted by eosinophil count, peak thrombin generation, factor VIII, and soluble CD40 ligand, whereas eosinophil count, peak thrombin generation and antiplasmin predicted t50%.Conclusion
This study is the first to show that EGPA is associated with prothrombotic plasma fibrin clot phenotype, which may contribute to thromboembolic manifestations reported in this disease. 相似文献125.
Introduction
In the light of evidence for the increased heat shock proteins (HSP) expression in neurodegenerative disorders, the presence of the adaptive humoral response of the immune system can be expected. The aim of the study was to check whether Parkinson’s disease (PD) has the ability to elicit immune response against small heat shock proteins.Methods
IgG and IgM autoantibodies against alpha B-crystallin were assessed in 26 PD patients 26 healthy subjects. For the assessment of anti-HSP IgG autoantibodies serum samples from 31 parkinsonian patients and 31 healthy control subjects were collected. Serum samples from PD patients and healthy control subjects were collected twice, at baseline and after mean of 13 months follow up.Results
Both IgM and IgG autoantibodies against alpha ß-crystallin in PD patients were significantly higher compared to healthy controls (p<0.05). We also found statistically significant increase in antibodies titers against alpha ß-crystallin over the time of 13 months, both for IgG (p = 0.021) and for IgM (p<0.0001). Additionally, PD patients presented higher levels of anti-HSP IgG autoantibodies than healthy controls (p = 0.02).Conclusions
Increase of IgG and IgM autoantibodies against alpha B-crystallin in PD patients over time may suggest their involvement in the disease pathogenesis and progression. Further studies are required to confirm the role of this antibody as a biomarker of the disease progression. 相似文献126.
127.
Adam Jozwiak Magdalena Ples Karolina Skorupinska-Tudek Magdalena Kania Marta Dydak Witold Danikiewicz Ewa Swiezewska 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2013,1831(2):438-447
Sugars are recognized as signaling molecules regulating the biosynthesis of secondary metabolites in plants. Here, a modulatory effect of sugars on dolichol and phytosterol profiles was noted in the hairy roots of Arabidopsis thaliana. Arabidopsis roots contain a complex dolichol mixture comprising three groups (‘families’) of dolichols differing in the chain-length. These dolichols, especially the longest ones are accompanied by considerable amounts of polyprenols of the same length. The spectrum of polyisoprenoid alcohols, i.e. dolichols and polyprenols, was dependent on sugar type (glucose or sucrose) and its concentration in the medium. Among the long-chain dolichols Dol/Pren-20 (dolichol or prenol molecule composed of 20 isoprene residues) and Dol/Pren-23 were the main components at 0.5% and 2% glucose, respectively. Moreover, the ratio of polyprenols versus respective dolichols was also modulated by sugar in this group of polyisoprenoids, with polyprenols dominating at 3% sucrose and dolichols at 2% glucose. Glucose concentration affected the expression level of genes encoding cis-prenyltransferases, enzymes responsible for elongation of the polyisoprenoid chain. The most abundant phytosterols of the A. thaliana roots, β-sitosterol, stigmasterol and campesterol, were accompanied by corresponding stanols and traces of brassicasterol, stigmast-4,22-dien-3-one and stigmast-4-en-3-one. Similar to the polyisoprenoids, sterol profile responded to the sugar present in the medium, β-sitosterol dominating in roots grown on 3% or lower glucose concentrations and stigmasterol in 3% sucrose. These results indicate an involvement of sugar signaling in the regulation of cis-prenyltransferases and phytosterol pathway enzymes. 相似文献
128.
Nowacka-Woszuk J Cieslak J Skowronska B Majewska KA Stankiewicz W Fichna P Switonski M 《Journal of applied genetics》2011,52(3):319-323
Extensive studies of the MC4R gene polymorphism showed that, among numerous variants, there are mutations responsible for monogenic obesity, as well as
polymorphisms negatively correlated with the risk of obesity. In this report, we present the first studies of the whole coding
sequence of the MC4R gene in 243 Polish obese children and adolescents (the mean relative body mass index [RBMI] was 163.6). In addition, 101
non-obese adults were also analyzed. Direct sequencing facilitated the identification of six missense (K73R, V103I, T112M,
S127L, M215L, and I251L) and one silent (c.756 C > T) single-nucleotide polymorphisms (SNPs). Two non-synonymous polymorphisms
(K73R and M215L) appeared to be novel and one was found in obese patients (M215L, one patient) and one in non-obese adults
(K73R, one person). The overall frequency of non-synonymous variant carriers reached 4.1% and 6.9% in obese patients and non-obese
adults, respectively. Only one obesity-associated variant (127L) was found in two obese patients (0.82%) and in two non-obese
adults (1.98%). The obesity-protecting variants (103I and 251L) appeared to be the most common in both groups: 3.3% and 4.0%,
respectively. It was also observed that the RBMI in obese children and adolescents carrying the minor variants did not differ
significantly from the non-carriers; however, the expected trends for the associated and protecting variants were observed.
We conclude that the contribution of the MC4R gene variants to the pathogenesis of obesity in Polish children and adolescents is low. 相似文献
129.
Ma?gorzata Wierzbicka Mariola Popko Karolina Piskad?o Rafa? Czepczyński Aleksandra Stankowska Tomasz Pi?tka Miros?aw Dziuk Witold Szyfter 《Reports of Practical Oncology and Radiotherapy》2011,16(5):184-188
Background
Posttreatment surveillance for the local and regional recurrence of the head and neck squamous cell carcinoma often requires a multimodality techniques that include PET combined with CT, MRI, US.Aim
The purpose of this study is to compare the diagnostic performance of two imaging techniques (PET/CT and US), and their combined use for the detection of a subclinical regional recurrence in patients after HNSCC treatment.Materials and methods
83 patients after completion of the HNSCC treatment underwent both US and PET/CT on the mean follow-up of 14 months after initial treatment.Results
The sensitivity and specificity of PET/CT were 86% and 82%, respectively; US values reached 81% and 87%, respectively. PPV was 79% for PET/CT, and 83% for US. NPV was 89% for PET/CT, and 85% for US. The overall accuracy for PET/CT and US was 84% for both methods.Conclusion
US could be regarded as complementary to PET/CT as the procedures with highest sensitivity, specificity and NPV for detecting subclinical regional recurrences after HNSCC treatment. 相似文献130.
Oxidative stress is known to play important roles in engineered nanomaterial‐induced cellular toxicity. However, the proteins and signaling pathways associated with the engineered nanomaterial‐mediated oxidative stress and toxicity are largely unknown. To identify these toxicity pathways and networks that are associated with exposure to engineered nanomaterials, an integrated proteomic study was conducted using human bronchial epithelial cells, BEAS‐2B and nanoscale titanium dioxide. Utilizing 2‐DE and MS, we identified 46 proteins that were altered at protein expression levels. The protein changes detected by 2‐DE/MS were verified by functional protein assays. These identified proteins include some key proteins involved in cellular stress response, metabolism, adhesion, cytoskeletal dynamics, cell growth, cell death, and cell signaling. The differentially expressed proteins were mapped using Ingenuity Pathway Analyses? canonical pathways and Ingenuity Pathway Analyses tox lists to create protein‐interacting networks and proteomic pathways. Twenty protein canonical pathways and tox lists were generated, and these pathways were compared to signaling pathways generated from genomic analyses of BEAS‐2B cells treated with titanium dioxide. There was a significant overlap in the specific pathways and lists generated from the proteomic and the genomic data. In addition, we also analyzed the phosphorylation profiles of protein kinases in titanium dioxide‐treated BEAS‐2B cells for a better understanding of upstream signaling pathways in response to the titanium dioxide treatment and the induced oxidative stress. In summary, the present study provides the first protein‐interacting network maps and novel insights into the biological responses and potential toxicity and detoxification pathways of titanium dioxide. 相似文献