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391.
Urszula Wysmyk Simo S. Oja Pirjo Saransaari Jan Albrecht 《Neurochemical research》1992,17(12):1187-1190
The release of newly loaded [3H]GABA was studied in slices of different brain regions derived from rats in which acute hepatic encephalopathy (HE) was induced with a hepatotoxin thioacetamide. HE increased both spontaneous and high (50 mM) ammonium chloride-evoked GABA release in cerebral cortical slices by 38% and 50%, respectively. No effects of HE were noted in cerebellar or striatal slices. An increased release of GABA in the cerebral cortex may contribute to the endogenous benzodiazepine-mediated enhancement of GABAergic tone, which is thought to be partly responsible for the pathophysiological mechanism of HE. 相似文献
392.
Identification of novel small-molecule inhibitors of West Nile virus infection 总被引:1,自引:0,他引:1
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Noueiry AO Olivo PD Slomczynska U Zhou Y Buscher B Geiss B Engle M Roth RM Chung KM Samuel M Diamond MS 《Journal of virology》2007,81(21):11992-12004
West Nile virus (WNV) has spread throughout the United States and Canada and now annually causes a clinical spectrum of human disease ranging from a self-limiting acute febrile illness to acute flaccid paralysis and lethal encephalitis. No therapy or vaccine is currently approved for use in humans. Using high-throughput screening assays that included a luciferase expressing WNV subgenomic replicon and an NS1 capture enzyme-linked immunosorbent assay, we evaluated a chemical library of over 80,000 compounds for their capacity to inhibit WNV replication. We identified 10 compounds with strong inhibitory activity against genetically diverse WNV and Kunjin virus isolates. Many of the inhibitory compounds belonged to a chemical family of secondary sulfonamides and have not been described previously to inhibit WNV or other related or unrelated viruses. Several of these compounds inhibited WNV infection in the submicromolar range, had selectivity indices of greater than 10, and inhibited replication of other flaviviruses, including dengue and yellow fever viruses. One of the most promising compounds, AP30451, specifically blocked translation of a yellow fever virus replicon but not a Sindbis virus replicon or an internal ribosome entry site containing mRNA. Overall, these compounds comprise a novel class of promising inhibitors for therapy against WNV and other flavivirus infections in humans. 相似文献
393.
394.
Skala E Kalemba D Wajs A Rózalski M Krajewska U Rózalska B Wieckowska-Szakiel M Wysokińska H 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(11-12):839-848
The procedure of Salvia przewalskii shoot multiplication and the ability of regenerated plants to produce essential oil is reported. The essential oil was obtained by hydrodistillation from leaves and flowering stems of field-grown plants, and their chemical composition was examined by GC, GC-MS and 1H NMR. The differences in yield as well as qualitative and quantitative composition between the oils isolated from in vitro and in vivo plants were observed. S. przewalskii essential oil was tested for its antimicrobial and cytotoxic properties. It was found that cytotoxicity against human leukemia HL-60 cells and antimicrobial activity (especially, against Staphylococcus aureus and S. epidermidis strains) of oils isolated from in vitro plants were higher than those for oils from in vivo S. przewalskii plants. 相似文献
395.
396.
Krwawicz J Arczewska KD Speina E Maciejewska A Grzesiuk E 《Acta biochimica Polonica》2007,54(3):413-434
Base excision repair (BER) pathway executed by a complex network of proteins is the major system responsible for the removal of damaged DNA bases and repair of DNA single strand breaks (SSBs) generated by environmental agents, such as certain cancer therapies, or arising spontaneously during cellular metabolism. Both modified DNA bases and SSBs with ends other than 3'-OH and 5'-P are repaired either by replacement of a single or of more nucleotides in the processes called short-patch BER (SP-BER) or long-patch BER (LP-BER), respectively. In contrast to Escherichia coli cells, in human ones, the two BER sub-pathways are operated by different sets of proteins. In this review the selection between SP- and LP-BER and mutations in BER and end-processors genes and their contribution to bacterial mutagenesis and human diseases are considered. 相似文献
397.
Czarnik U Grzybowski G Kamiński S Prusak B Zabolewicz T 《Journal of applied genetics》2007,48(4):375-377
The molecular basis of BLAD is the D128G mutation of the gene coding for the CD18 subunit of beta-2 integrin. This mutation is lethal, since homozygous (BL/BL) animals die before they reach sexual maturity. In the 1990s, BLAD was the most widespread genetic disease in HF cattle worldwide. The aim of the present study was to determine the frequency of BLAD carriers among 4645 young breeding bulls in Poland in 1995-2006. The frequency of carriers of the mutated allele showed a clear decreasing trend. The highest frequency (7.9%) was recorded while implementing the BLAD control program (1995-1997). Regular monitoring has enabled a great reduction of this threat to the tested population. Today only sporadic cases of BL/TL heterozygotes are reported (ca. 0.8% in 2004-2006). 相似文献
398.
Urszula Maciejewska Janusz S. Skierski Anna Szczerbakowa 《Acta Physiologiae Plantarum》1999,21(1):37-43
The DNA relative content in nuclei from several Solanum species, which were used as partners for somatic hybridization, were determined using a flow cytometry method. The nuclei
were isolated mechanically or via protoplasts from leaves of in vitro grown plants. In the case of S. nigrum as well as S. tuberosum cv. Bzura and dihaploid clone H8105, the nuclei were also obtained from suspension cultured cells by lysis of protoplasts. The
source and the method of nuclei isolation affected the pattern of nuclear DNA in the genotypes studied. The mesophyll nuclei
showed two distinct peaks on the DNA histograms, whereas the DNA peaks produced by cell suspension nuclei were broad and less
distinct. The DNA content in the nuclei, calculated from the DNA histograms of the samples and a DNA standard historgam (Trout
Red Blood Cells, having DNA content of 5.05 pg per nucleus), were much lower in mesophyll nuclei than in those obtained from
the cell suspension for the same genotypes. The results are discussed in respect of the genetic instability of Solanum genotypes. The usefulness of a flow cytometry approach in somatic hybridization research is also discussed. 相似文献
399.
Urszula Tylewicz Valentina Panarese Luca Laghi Pietro Rocculi Ma?gorzata Nowacka Giuseppe Placucci Marco Dalla Rosa 《Food biophysics》2011,6(2):327-333
This study investigated mass transfer and water state changes promoted by osmotic dehydration on two kiwifruit species, Actinidia deliciosa and Actinidia chinensis. Osmotic treatment was performed in a 61.5% w/v sucrose solution at three different temperatures (25, 35 and 45 °C), with treatment time from 0 to 300 min. Treatment time
positively influenced kiwifruit water loss and solid gain while temperature significantly affected only water loss. Peleg’s
model highlighted that the main response differences between the two species occurred during the initial phase of the osmotic
treatment. Thermal properties and relaxation time measurements offered a complementary view concerning the effects of osmotic
dehydration on kiwifruit. DSC parameters appeared to be sensitive to water and solid exchange between fruit and osmotic solution.
LF-NMR proton T2 revealed the consequences of the water–solid exchange on the cell compartments, namely vacuole, cytoplasm plus extracellular
space and cell wall. During the osmotic treatment, the initial freezing temperature and the freezable water content decrease
was dependent on time and treatment temperature, showing a similar tendency for both the kiwifruit species. They evidenced
the same treatment response also concerning the reduction of vacuole and the increase of cytoplasm plus extracellular space
T2 values. 相似文献
400.
Marta Grochowska Tomasz Laskus Marcin Paciorek Agnieszka Pollak Urszula Lechowicz Micha Makowiecki Andrzej Horban Marek Radkowski Karol Perlejewski 《Current issues in molecular biology》2022,44(7):2903
There are multiple lines of evidence for the existence of communication between the central nervous system (CNS), gut, and intestinal microbiome. Despite extensive analysis conducted on various neurological disorders, the gut microbiome was not yet analyzed in neuroinfections. In the current study, we analyzed the gut microbiome in 47 consecutive patients hospitalized with neuroinfection (26 patients had viral encephalitis/meningitis; 8 patients had bacterial meningitis) and in 20 matched for age and gender health controls. Using the QIIME pipeline, 16S rRNA sequencing and classification into operational taxonomic units (OTUs) were performed on the earliest stool sample available. Bacterial taxa such as Clostridium, Anaerostipes, Lachnobacterium, Lachnospira, and Roseburia were decreased in patients with neuroinfection when compared to controls. Alpha diversity metrics showed lower within-sample diversity in patients with neuroinfections, though there were no differences in beta diversity. Furthermore, there was no significant change by short-term (1–3 days) antibiotic treatment on the gut microbiota, although alpha diversity metrics, such as Chao1 and Shannon’s index, were close to being statistically significant. The cause of differences between patients with neuroinfections and controls is unclear and could be due to inflammation accompanying the disease; however, the effect of diet modification and/or hospitalization cannot be excluded. 相似文献