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61.
Wojciech Szewczyk Hanna Kwaśna Jolanta Behnke‐Borowczyk 《Journal of Phytopathology》2017,165(7-8):500-507
Abundance and diversity of fungi in naturally formed knots of Pinus sylvestris affected by Porodaedalea pini were investigated. Samples were taken from trees that were (i) affected, with internal heartwood decay and no conks, (ii) affected, with internal heartwood decay and conks and (iii) controls. The Illumina sequencing technology was used for amplification of DNA, sequencing and analysis. In total, 566,279 raw sequences were obtained from six samples. Sequences included 74% of culturable and 8.4% of non‐culturable fungi and 17.6% of organisms with no reference sequences in NCBI. Abundance of organisms in knotwood, measured as number of OTUs, ranged from 36,272 (29,506 for fungi) to 178,535 (177,484 for fungi) and differed significantly between two trees in a stand and between stands. The highest and lowest average number of fungal OTUs occurred in infected trees with no conks and in trees with conks, respectively. Number of taxa ranged from 171 to 415 and often differed significantly between two trees in one stand and between stands. Greatest diversity occurred in control trees. The number of fungal taxa shared by two trees in one stand was 67–152 and that shared by two stands was 51–141. The majority of fungi were Ascomycota. Those most common in pines affected by P. pini were Coniochaeta hoffmannii and C. fodinicola (19.65%–59.92%). Infundichalara microchona, Leotiomycetes spp. and Rhinocladiella atrovirens were also present. Another common species, Lecanora conizaeoides, occurred most often in control trees (0.30%–8.82%). Porodaedalea pini was detected only sporadically. Non‐culturable fungi were most frequent in the control trees. The greater average abundance and smaller average diversity of fungi in knots of trees infected by P. pini suggest that the pathogen successfully competes with some fungal species and does not inhibit the growth of survivors. Some fungi detected may contribute to production of natural biocides. 相似文献
62.
Rupert CM Jones Maria Dickson-Spillmann Martin JC Mather Dawn Marks Bryanie S Shackell 《Respiratory research》2008,9(1):62
Background
Guidelines on COPD diagnosis and management encourage primary care physicians to detect the disease at an early stage and to treat patients according to their condition and needs. Problems in guideline implementation include difficulties in diagnosis, using spirometry and the disputed role of reversibility testing. These lead to inaccurate diagnostic registers and inadequacy of administered treatments. This study represents an audit of COPD diagnosis and management in primary care practices in Devon.Methods
Six hundred and thirty two patients on COPD registers in primary care practices were seen by a visiting Respiratory Specialist Nurse. Diagnoses were made according to the NICE guidelines. Reversibility testing was carried out either routinely or based on clinical indication in two sub-samples. Dyspnoea was assessed. Data were entered into a novel IT-based software which computed guideline-based treatment recommendations. Current and recommended treatments were compared.Results
Five hundred and eighty patients had spirometry. Diagnoses of COPD were confirmed in 422 patients (73%). Thirty nine patients were identified as asthma only, 94 had normal spirometry, 23 were restrictive and 2 had a cardiac disorder. Reversibility testing changed diagnosis of 11% of patients with airflow obstruction, and severity grading in 18%. Three quarters of patients with COPD had been offered practical help with smoking cessation. Short and long-acting anticholinergics and long acting beta-2 agonists had been under-prescribed; in 15–18% of patients they were indicated but not received. Inhaled steroids had been over-prescribed (recommended in 17%; taken by 60%), whereas only 4% of patients with a chronic productive cough were receiving mucolytics. Pulmonary rehabilitation was not available in some areas and was under-used in other areas.Conclusion
Diagnostic registers of COPD in primary care contain mistakes leading to inaccurate prevalence estimates and inappropriate treatment decisions. Use of pre-bronchodilator readings for diagnosis overestimates the prevalence and severity in a significant minority, thus post bronchodilator readings should be used. Management of stable COPD does often not correspond to guidelines. The IT system used in this study has the potential to improve diagnosis and management of COPD in primary care. 相似文献63.
PJS Amaral LFM Finotelo EHC De Oliveira A Pissinatti CY Nagamachi JC Pieczarka 《BMC evolutionary biology》2008,8(1):169
Background
Chromosomal painting, using whole chromosome probes from humans and Saguinus oedipus, was used to establish karyotypic divergence among species of the genus Cebus, including C. olivaceus, C. albifrons, C. apella robustus and C. apella paraguayanus. Cytogenetic studies suggested that the species of this genus have conservative karyotypes, with diploid numbers ranging from 2n = 52 to 2n = 54. 相似文献64.
Wrzosek A Łojek A Stanisławska I Chmura-Skirlińska A Dołowy K Chłopicki S Szewczyk A 《Postepy biochemii》2008,54(2):198-208
Vascular endothelium the inside layer of the cardiovascular system is presently looked upon as an important paracrine, autocrine and endocrine organ that determines the health of the cardiovascular system. In fact, healthy endothelium is essential for homeostasis of cardiovascular system, while endothelial dyfunction leads to cardiovascular diseases including atherosclerosis, diabetes and heart failure. Endothelial dysfunction is tightly linked to the overproduction of reactive oxygen species, development of oxidant stress and inflammatory response of endothelium. Mitochondria of the vascular endothelium seem to be an important player in these processes. In contrast to numerous cell types, synthesis of ATP in endothelium occurs in major part via a glycolytic pathway and endothelium seem to be relatively independent of the mitochondrial pathway of energy supply. However, as evident from recent studies, mitochondrial pathways of free radicals production tighly linked to mitochondrial and cytosol changes in the ion homeostasis play an important role in the regulation of endothelial inflammatory response, in the development of oxidative stress and apoptosis of vascular endothelium. Therefore, endothelial mitochondria appears critical in the regulation of endothelial functions and represent a novel target in pharmacology of endothelial dysfunction in cardiovascular diseases. 相似文献
65.
Katarzyna Choma Piotr Bednarczyk Izabela Koszela-Piotrowska Bogusz Kulawiak Alexei Kudin Wolfram S. Kunz Krzysztof Dołowy Adam Szewczyk 《Journal of bioenergetics and biomembranes》2009,41(4):323-334
Mitochondrial potassium channels in the brain have been suggested to have an important role in neuroprotection. The single
channel activity of mitochondrial potassium channels was measured after reconstitution of the purified inner membrane from
rat brain mitochondria into a planar lipid bilayer. In addition to a large conductance potassium channel that was described
previously, we identified a potassium channel that has a mean conductance of 219 ± 15 pS. The activity of this channel was
inhibited by ATP/Mg2+ and activated by the potassium channel opener BMS191095. Channel activity was not influenced either by 5-hydroxydecanoic
acid, an inhibitor of mitochondrial ATP-regulated potassium channels, or by the plasma membrane ATP-regulated potassium channel
blocker HMR1098. Likewise, this mitochondrial potassium channel was unaffected by the large conductance potassium channel
inhibitor iberiotoxin or by the voltage-dependent potassium channel inhibitor margatoxin. The amplitude of the conductance
was lowered by magnesium ions, but the opening ability was unaffected. Immunological studies identified the Kir6.1 channel
subunit in the inner membrane from rat brain mitochondria. Taken together, our results demonstrate for the first time the
single channel activity and properties of an ATP-regulated potassium channel from rat brain mitochondria. 相似文献
66.
Matkovic K Koszela-Piotrowska I Jarmuszkiewicz W Szewczyk A 《Biochimica et biophysica acta》2011,1807(3):275-285
Single-ion channel activities were measured after reconstitution of potato tuber mitochondrial inner membranes into planar lipid bilayers. In addition to the recently described large-conductance Ca(2+)-activated potassium channel activity (Koszela-Piotrowska et al., 2009), the following mitochondrial ion conductance pathways were recorded: (i) an ATP-regulated potassium channel (mitoK(ATP) channel) activity with a conductance of 164+/-8pS, (ii) a large-conductance Ca(2+)-insensitive iberiotoxin-sensitive potassium channel activity with a conductance of 312 pS+/-23, and (iii) a chloride 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS)-inhibited channel activity with a conductance of 117 pS+/-4. In isolated non-phosphorylating potato tuber mitochondria, individual and combined potassium channel activities caused significant (up to 14mV) but not collapsing K(+)-influx-induced membrane potential depolarisation. Under phosphorylating conditions, the coupling parameters were unchanged in the presence of high K(+) level, indicating that plant K(+) channels function as energy-dissipating systems that are not able to divert energy from oxidative phosphorylation. A potato tuber K(+) channel that is ATP-, 5-hydroxydecanonic acid-, glybenclamide-inhibited and diazoxide-stimulated caused low cation flux, modestly decreasing membrane potential (up to a few mV) and increasing respiration in non-phosphorylating mitochondria. Immunological analysis with antibodies raised against the mammalian plasma membrane ATP-regulated K(+) channel identified a pore-forming subunit of the Kir-like family in potato tuber mitochondrial inner membrane. These results suggest that a mitoK(ATP) channel similar to that of mammalian mitochondria is present in potato tuber mitochondria. 相似文献
67.
Rabbit hemorrhagic disease virus (RHDV) which causes a highly contagious disease of wild and domestic rabbits belongs to the family Caliciviridae. It is a small, positive single-stranded RNA virus with a genome of 7.5 kb and has a diameter of approximately 40 nm. In negatively stained electron micrographs the virus shows typical calicivirus morphology with regularly arranged cup-shaped structures on the surface. It is a major pathogen of rabbits in many countries. Vp60 - a coat protein of molecular mass around 60 kDa is the major antigen of RHDV. It is present as 90 dimeric units per virion particle. We have expressed VP60 gene in the baculovirus system with the aim to use it as a potential vaccine against RHDV and a diagnostic reagent in immunological tests. cDNA of the vp60 gene of strain SGM, was cloned into a baculovirus transfer vector as full-length gene, as well as truncated gene lacking 600 5'-terminal nucleotides. The sequence of SGM VP60 differed markedly from that of the reference strain. Full-length recombinant VP60 protein from the SGM strain self-assembled to form virus-like particles (VLPs). These particles observed by electron microscopy were morphologically similar to native virions and were able to agglutinate human group 0 erythrocytes. After immunization the recombinant particles induced RHDV-specific antibodies in rabbits and guinea pigs. Rabbits immunized with the VLPs were fully protected against challenge with a virulent RHDV. 相似文献
68.
Anna Bogucka-Kocka Christian Zidorn Małgorzata Kasprzycka Grażyna Szymczak Katarzyna Szewczyk 《Saudi Journal of Biological Sciences》2018,25(4):622-630
Phenolic acid composition, antioxidant, and cytotoxic activities in leaves of four Kalanchoe (Crassulaceae) species were evaluated. Determination of phenolic acid contents were conducted by an optimized LC–ESI-MS/MS method. The results show that Kalanchoe daigremontiana Raym.-Hamet & H. Perrier (using ASE extraction) and Kalanchoe pinnata (Lam.) Pers. contain the highest amounts of phenolic acids, while Kalanchoe nyikae Engl. the lowest ones. Among phenolic acids ferulic, caffeic and protocatechuic acids were occurring in the highest quantities in the analysed species. The greatest amounts of ferulic and protocatechuic acids were found in K. daigremontiana and K. pinnata. Moreover, the antiradical and cytotoxic activities of Kalanchoe extracts were investigated. All tested extracts possessed antioxidant activity. The obtained IC50 values (μg/mL) ranged from 49.9 μg/mL to 1410 μg/mL, indicating a large variation of the activity of the analysed extracts. Cytotoxicity assays revealed dose-dependent effects in the cells lines tested. Only K. pinnata extract showed a high cytotoxicity against the H-9 human T cell line. Other extracts (K. daigremontiana, Kalanchoe milloti, K. nyikae) showed more pronounced cytotoxicity towards J45.01 cells (human acute lymphoblastic leukaemia T cells).The present study demonstrated that Kalanchoe extracts have significant antioxidant and cytotoxic effects. This suggests that these species can be used as new sources of natural antioxidants and potential anticancer compounds. 相似文献
69.
70.
Anna Stojakowska Janusz Malarz Agnieszka Szewczyk Wanda Kisiel 《Acta Physiologiae Plantarum》2012,34(1):291-298
In a search for biologically active phenolics, a hydroalcoholic extract from the hairy roots of Lactuca virosa was fractionated by chromatographical methods. The procedure led to the isolation of a substantial amount of 3,5-dicaffeoylquinic
acid (3,5-DCQA)—a potent free radical scavenger. An analytical RP-HPLC separation of the hydroalcoholic extract from the hairy
roots allowed identification of further hydroxycinnamates: caftaric acid (CTA), chlorogenic acid (5-CQA) and cichoric acid
(DCTA), as well as small amounts of unbound phenolic acids. A time course of growth and caffeic acid derivatives accumulation
in the hairy root culture was also investigated. The highest contents of the compounds in the examined roots were detected
at the logarithmic phase of growth. The average content of 3,5-DCQA in the roots (ca. 2.5% DW) was at least one order of magnitude
higher than that found in roots of Lactuca species and callus culture of L. virosa. 相似文献