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61.
BACKGROUND: Different forms of chronic airway inflammation may involve diverse pathogenic elements. In general, deficient defence response is a feature of chronic obstructive pulmonary disease (COPD), whereas distorted immunoregulatory mechanisms lead to development of asthmatic symptoms. In addition to diverse effector mechanisms, the cellular and humoral elements participating in the development of immune response may appear to be different in COPD and bronchial asthma (BA) patients. AIMS: To evaluate the immunoregulatory properties of T cells and monocytes in cultures of peripheral blood mononuclear cells (PBMC) and to determine the chosen cytokine profiles in COPD and BA patients. METHODS: The microcultures of PBMC from COPD and BA patients were assessed for the T-cell response to mitogens, saturation of interleukin (IL)-2 receptors, T-cell suppressive activity and monokine influence on lymphocyte proliferation. Concomitantly, the cytokine (IL-1beta, interleukin-1 receptor antagonist, tumour necrosis factor-alpha, IL-4, IL-6, IL-8) concentrations were determined in the serum, the broncho-alveolar lavage fluid and in the culture supernatants. RESULTS: The T-lymphocyte reactions (response to phytohaemagglutinin, IL-2 receptor saturation, suppressive activity) were lower in BA patients than in COPD patients. Reversely, the immunogenic activity of monocytes (IL-1beta versus IL-1ra production) was higher in BA patients than in COPD patients. The highest values of cytokine concentrations were found in the culture supernatants. The concentrations of tumour necrosis factor-alpha, IL-4, IL-6 and IL-8 were significantly higher and the concentration of IL-1ra was lower in BA patients than in COPD patients. CONCLUSION: The assessments of cellular immunoregulatory properties and cytokine profiles in the cultures of blood mononuclear cells may prove helpful for diagnostic and therapeutic discrimination between BA and COPD patients. 相似文献
62.
Bocianowski J Chełkowski J Kuczyńska A Wiśniewska H Surma M Adamski T 《Journal of applied genetics》2003,44(3):355-360
Thirty doubled haploid (DH) lines of barley derived from F(1) of a cross between the six-rowed cultivar Pomo and two-rowed cultivar Maresi were examined for susceptibility to Fusarium seedling blight (SB) and head blight (FHB), measured by mycotoxin (nivalenol) content of kernels. RAPD (random amplified polymorphic DNA) polymorphism was analysed by using 53 decamer primers. Amplification products (APs) were 200 bp up to 2000 bp in size on average 5.7 per primer and the total number of APs was 284, 51.06% of which were polymorphic. Only 32 APs differentiated the examined DH lines - 19 APs for nivalenol content of kernels and 13 for seedling resistance. DH lines segregated with continuous distribution of resistance to FHB and SB. At the seedling stage all DH lines exhibited lower susceptibility than parental cultivars, but in the adult stage only two lines (MP 2 and MP 7) appeared to be more resistant to FHB, i.e. accumulated in kernels a lower amount of mycotoxin than cultivars Maresi and Pomo. 相似文献
63.
Dzierzewicz Z Szczerba J Weglarz L Swiatkowska L Jasinska D Wilczok T 《FEMS microbiology letters》2003,222(1):69-74
Fifteen (soil and intestinal) strains of Desulfovibrio desulfuricans species were typed by PCR method with the use of primers specific for repetitive extragenic palindromic (REP) and enterobacterial repetitive intergenic consensus (ERIC) sequences. As a result, characteristic DNA fingerprints for the strains were obtained. Moreover, the genetic profiles were found to be useful for typing and distinguishing the strains of D. desulfuricans. According to cluster analysis, PCR with primers complementary to the sequences REP appeared to be slightly more discriminatory than PCR with ERIC primers for the investigated strains. Distinct fingerprint patterns of two isolates derived from the same patient pointed to the different origin of both strains. 相似文献
64.
Uncoupling protein-2 prevents neuronal death and diminishes brain dysfunction after stroke and brain trauma 总被引:28,自引:0,他引:28
Mattiasson G Shamloo M Gido G Mathi K Tomasevic G Yi S Warden CH Castilho RF Melcher T Gonzalez-Zulueta M Nikolich K Wieloch T 《Nature medicine》2003,9(8):1062-1068
Whereas uncoupling protein 1 (UCP-1) is clearly involved in thermogenesis, the role of UCP-2 is less clear. Using hybridization, cloning techniques and cDNA array analysis to identify inducible neuroprotective genes, we found that neuronal survival correlates with increased expression of Ucp2. In mice overexpressing human UCP-2, brain damage was diminished after experimental stroke and traumatic brain injury, and neurological recovery was enhanced. In cultured cortical neurons, UCP-2 reduced cell death and inhibited caspase-3 activation induced by oxygen and glucose deprivation. Mild mitochondrial uncoupling by 2,4-dinitrophenol (DNP) reduced neuronal death, and UCP-2 activity was enhanced by palmitic acid in isolated mitochondria. Also in isolated mitochondria, UCP-2 shifted the release of reactive oxygen species from the mitochondrial matrix to the extramitochondrial space. We propose that UCP-2 is an inducible protein that is neuroprotective by activating cellular redox signaling or by inducing mild mitochondrial uncoupling that prevents the release of apoptogenic proteins. 相似文献
65.
The relationship between the age of leaf tissue and response of the photosynthetic apparatus and phytochelatin accumulation to Cd treatment was studied. Studies were carried out with seedlings of Zea mays L. cv. Hidosil grown in the presence of 100-200 mumol/L Cd for 14 days under low light conditions. The third leaf was divided into 3 segments of equal length differing in the stage of tissue maturity and used for measurements of chlorophyll content, chlorophyll fluorescence, glutathione and phytochelatin content and Cd accumulation. A close relationship between the age of leaf tissue and response of the photosynthetic apparatus to Cd was shown. Cadmium (200 mumol/L) reduced photochemical processes more in older than younger leaf segments as seen in the Chl fluorescence parameters Fv/F0, and t1/2, while the chlorophyll fluorescence decrease ratio (Rfd) was inhibited more strongly in younger ones. Fv/Fm was slightly affected. Cd-induced enhancement of GSH content was correlated with higher phytochelatin accumulation to a greater extent in younger than in older leaf segments. Phytochelatin level corresponded to changes of photochemical processes in older leaves. The peptide thiol:Cd molar ratio for the phytochelatins varied depending on Cd concentration and age of leaf segments. The protective role of phytochelatins for the photosynthetic apparatus is discussed. 相似文献
66.
Seasonal and longitudinal metabolic trends in benthic communities were studied in the five orders of a natural mountain river
(the Stradomka) in southern Poland. The method of oxygen change of rocky substrata in chambers was applied. Metabolic data
were compared with abiotic (light regime, channel geomorphology and stream hydrology), and water chemical variables. A tendency
of downstream increase in gross production and community respiration was observed between 1st and 4th stream orders. The highest
values of GP (0.94 g C m-2 24 h -1) and CR (1.12 g C m-2 24 h -1) were observed in the middle Stradomka course (3–4 orders) in spring. A distinct negative NDM (heterotrophy) of the benthic
community was measured in autumn and spring. During winter NDM was almost constant and oscillated around zero. The P/R ratio
changed according to season and fluctuated between heterotrophy (P/R < 1) and autotrophy (P/R > 1). In general, heterotrophy
prevailed in the study system (except 5th order). A marked shift in P/R between 4th and 5th stream orders confirms the prediction
included in the RCC. Water temperature and PAR accounted for 56% in GP variability, whereas CR and NDM were not related to
these variables. The combined variables (PAR and PO4–P) attributed to 69% in GP variability. The set of chemical factors was less related to Stradomka metabolic data. These results
suggest that metabolic processes in this mountain river remarkably depend on physical variables (solar radiation, altitude,
water temperature and conductivity). Metabolic parameters were similar to other geographical mountain systems.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
67.
Rüdiger Wagner Miroslav Barták Art Borkent Gregory Courtney Boudewijn Goddeeris Jean-Paul Haenni Lloyd Knutson Adrian Pont Graham E. Rotheray Rudolf Rozkošný Bradley Sinclair Norman Woodley Tadeusz Zatwarnicki Peter Zwick 《Hydrobiologia》2008,595(1):489-519
Today’s knowledge of worldwide species diversity of 19 families of aquatic Diptera in Continental Waters is presented. Nevertheless,
we have to face for certain in most groups a restricted knowledge about distribution, ecology and systematic, particularly
in the tropical environments. At the same time we realize a dramatically decline or even lack of specialists being able, having
the time or the opportunity to extend or even secure the present information. The respective families with approximate numbers
of aquatic species are: Blephariceridae (308), Deuterophlebiidae (14), Nyphomyiidae (7), Psychodidae (∼2.000), Scatopsidae
(∼5), Tanyderidae (41), Ptychopteridae (69), Dixidae (173), Corethrellidae (97), Chaoboridae (∼50), Thaumaleidae (∼170), Ceratopogonidae
(∼6.000), Stratiomyidae (∼43), Empididae (∼660), Lonchopteridae (2), Syrphidae (∼1.080), Sciomyzidae (∼190), Ephydridae (∼1.500),
Muscidae (∼870). Numbers of aquatic species will surely increase with increased ecological and taxonomical efforts.
Guest editors: E. V. Balian, C. Lévêque, H. Segers & K. Martens
Freshwater Animal Diversity Assessment 相似文献
68.
Bernt Engelsen Eva Westerberg Frode Fonnum† Tadeusz Wieloch 《Journal of neurochemistry》1986,47(5):1634-1641
Abstract The glutamate (Glu) terminals in rat neostriatum were removed by a unilateral frontal decortication. One to two weeks later the effects of insulin-induced hypoglycemia on the steady-state levels of amino acids [Glu, glutamine (Gin), aspartate (Asp), γ-aminobutyric acid (GABA), tau-rine] and energy metabolites (glucose, glycogen, α-ketoglu-tarate, pyruvate, lactate, ATP, ADP, AMP, phosphocre-atine) were examined in the intact and decorticated neostriatum from brains frozen in situ. The changes in the metabolite levels were examined during normoglycemia, hypoglycemia with burst-suppression (BS) EEG, after 5 and 30 min of hypoglycemic coma with isoelectric EEG, and 1 h of recovery following 30 min of isoelectric EEG. In normoglycemia Glu decreased and Gin and glycogen increased significantly on the decorticated side. During the BS period no significant differences in the measured compounds were noted between the two sides. After 5 min of isoelectric EEG Glu, Gin, GABA, and ATP levels were significantly lower and Asp higher on the intact than on the decorticated side. No differences between the two sides were found after 30 min of isoelectric EEG. After 1 h of recovery from 30 min of isoelectric EEG Glu, Gin, and glycogen had not reached their control levels. Glu was significantly lower, and Gin and glycogen higher on the decorticated side. The Asp and GABA levels were not significantly different from control levels. The results indicate that the turnover of Glu is higher in the intact than in decorticated neostriatum during profound hypoglycemia. 相似文献
69.
Panek M Pietras T Antczak A Górski P Kuna P Szemraj J 《Molecular biology reports》2012,39(4):4749-4757
N363S and ER22/23EK polymorphisms observed within glucocorticoid receptor gene (NR3C1) may play an important role in the development
of bronchial asthma. NR3C1 gene is associated with an altered sensitivity to GCs. The aim of the research project was to study
the correlation between this NR3C1 gene polymorphisms and occurrence of asthma in the population of Polish asthmatics. Peripheral
blood was obtained from 207 healthy volunteers and 221 asthma patients. Genotyping was carried out with PCR-RFLP method. In
the groups of patients with uncontrolled moderate asthma and uncontrolled severe disease, the genotype distribution for the
investigated polymorphisms was as follows: N363S-AA, AG, GG occurring with 0.881/0.073/0.046 frequency and ER22/23EK-GG, GA,
AA occurring with 0.963/0.037/0.000 frequency. Chi-square analysis revealed a significantly different (P < 0.05) distribution between cases and controls for the N363S polymorphisms. The N363S polymorphism of NR3C1 gene is significantly
associated with bronchial asthma, susceptibility to the development of moderate to severe form of uncontrolled bronchial asthma. 相似文献
70.
Halina Szatyłowicz Tadeusz Marek Krygowski Aneta Jezierska-Mazzarello 《Journal of molecular modeling》2011,17(1):125-131
Due to gradual and controlled changes of interatomic distances between heavy atoms in OH…F− of C6H5OH…F− systems it was possible to study the electronic structure evolution. Computation at B3LYP/6-311+G(d,p) level of theory was
performed for this purpose. Changes in charges at atoms and characteristics at bond critical points (BCPs) of the H-bond region
and also in distant parts of the systems were investigated by means of natural bond orbitals (NBO) and atoms in molecules
(AIM) analyses. It is shown that at the border line between partially covalent and non-covalent H-bonding (Espinosa et al.
in J Chem Phys 117:5529, 2002; Grabowski et al. in J Phys Chem B 110:6444, 2006) with the H…F interatomic distance ∼1.8 Ǻ the hydrogen atom has the most positive charge. In addition, the change in the
atomic charge values in the interacting region affects the phenyl ring properties. The decrease of the sum of atomic charges
as well as of the aromaticity was noticed when the OH….F distance is shortened. 相似文献