"2017"
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In most algae, NO3- assimilation is tightly controlled and is often inhibited by the presence of NH4+. In the marine, non-colonial, non-diazotrophic cyanobacterium Synechococcus UTEX 2380, NO3- assimilation is sensitive to NH4+ only when N does not limit growth. We sequenced the genome of Synechococcus UTEX 2380, studied the genetic organization of the nitrate assimilation related (NAR) genes, and investigated expression and kinetics of the main NAR enzymes, under N or light limitation. We found that Synechococcus UTEX 2380 is a β-cyanobacterium with a full complement of N uptake and assimilation genes and NAR regulatory elements. The nitrate reductase of our strain showed biphasic kinetics, previously observed only in freshwater or soil diazotrophic Synechococcus strains. Nitrite reductase and glutamine synthetase showed little response to our growth treatments, and their activity was usually much higher than that of nitrate reductase. NH4+ insensitivity of NAR genes may be associated with the stimulation of the binding of the regulator NtcA to NAR gene promoters by the high 2-oxoglutarate concentrations produced under N limitation. NH4+ sensitivity in energy-limited cells fits with the fact that, under these conditions, the use of NH4+ rather than NO3- decreases N-assimilation cost, whereas it would exacerbate N shortage under N limitation.
- Klíčová slova
- Ammonium, N metabolism, NtcA regulation, cyanobacteria, glutamine synthetase, limitation, nitrate reductase, nitrite reductase,
- MeSH
- bakteriální proteiny genetika metabolismus MeSH
- dusičnany metabolismus MeSH
- dusík metabolismus MeSH
- nitrátreduktasa genetika metabolismus MeSH
- Synechococcus * genetika metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- bakteriální proteiny MeSH
- dusičnany MeSH
- dusík MeSH
- nitrátreduktasa MeSH
Campylobacter jejuni is the most frequent cause of bacterial gastrointestinal food-borne infection worldwide. The transmission of Campylobacter and Arcobacter-like species is often made possible by their ability to adhere to various abiotic surfaces. This study is focused on monitoring the biofilm ability of 69 strains of Campylobacter spp. and lesser described species of the Arcobacteraceae family isolated from food, water, and clinical samples within the Czech Republic. Biofilm formation was monitored and evaluated under an aerobic/microaerophilic atmosphere after cultivation for 24 or 72 h depending on the surface material. An overall higher adhesion ability was observed in arcobacters. A chi-squared test showed no association between the origin of the strains and biofilm activity (p > 0.05). Arcobacter-like species are able to form biofilms under microaerophilic and aerobic conditions; however, they prefer microaerophilic environments. Biofilm formation has already been demonstrated at refrigerator temperatures (5 °C). Arcobacters also showed higher biofilm formation ability at the temperature of 30 °C. This is in contrast to Campylobacter jejuni NP 2896, which showed higher biofilm formation ability at temperatures of 5-30 °C. Overall, the results demonstrated the biofilm formation ability of many strains, which poses a considerable risk to the food industry, medical practice, and human health.
- Klíčová slova
- Aliarcobacter spp., Arcobacter-like, Campylobacter spp., abiotic surfaces, biofilm formation, food processing materials, temperature condition,
- Publikační typ
- časopisecké články MeSH
Heat stability (HS) is substantial technology property of raw milk. Analysis of sources of HS variation and its regular monitoring can contribute to creating higher added value in the dairy industry. The goal of this analysis was to assess the practice sources of raw cow milk HS variability on the results of an extensive data set of bulk tank milk samples. There was implemented neither a compositional technology modification nor acidity adjustment of milk, just original raw milk was used for the analysis. A total 2634 HS analyses were performed, including other milk indicators, during three years of an experimental period. The log HS mean and standard deviation were 1.273654 ± 0.144189, equal to the HS geometric mean of 18.8 min. Explanation of the HS variability through the linear model used was 41.1% (p < 0.0001). According to the results of the variance analysis, the milk HS was influenced (p = 0.0033 and mostly <0.0001) by all the farm factors such as year; season; calendar month; altitude; total annual rainfall; herd size by the number of cows; milk yield; cow breed; type of milking; litter type in the stable; summer grazing application; farm effect. During the calendar months (p < 0.0001), milk HS values suggest similar seasonal dynamics with the somatic cell count, total count of mesophilic microorganisms, coli bacteria count and urea and lactose concentration and opposite configuration pattern to fat, crude protein, solids-not-fat and total solids content and milk freezing point depression. Here performed quantification of these effects by analyzing the variance may allow efficient raw milk selection to be processed into specific dairy products.
- Klíčová slova
- breed, cow, farm factors, microbiologic indicators, milk composition, milk heat stability,
- Publikační typ
- časopisecké články MeSH
Cytokinins are adenine-based phytohormones that regulate key processes in plants, such as cell division and differentiation, root and shoot growth, apical dominance, branching, and seed germination. In preliminary studies, they have also shown protective activities against human neurodegenerative diseases. To extend knowledge of the protection (protective activity) they offer, we investigated activities of natural cytokinins against salsolinol (SAL)-induced toxicity (a Parkinson's disease model) and glutamate (Glu)-induced death of neuron-like dopaminergic SH-SY5Y cells. We found that kinetin-3-glucoside, cis-zeatin riboside, and N6-isopentenyladenosine were active in the SAL-induced PD model. In addition, trans-, cis-zeatin, and kinetin along with the iron chelator deferoxamine (DFO) and the necroptosis inhibitor necrostatin 1 (NEC-1) significantly reduced cell death rates in the Glu-induced model. Lactate dehydrogenase assays revealed that the cytokinins provided lower neuroprotective activity than DFO and NEC-1. Moreover, they reduced apoptotic caspase-3/7 activities less strongly than DFO. However, the cytokinins had very similar effects to DFO and NEC-1 on superoxide radical production. Overall, they showed protective activity in the SAL-induced model of parkinsonian neuronal cell death and Glu-induced model of oxidative damage mainly by reduction of oxidative stress.
- Klíčová slova
- Parkinson’s disease, cytokinin, cytotoxicity, glutamate, neuron-like SH-SY5Y cells, neuroprotection, oxidative stress, phytohormone, salsolinol,
- MeSH
- acetylcystein farmakologie MeSH
- biologické modely * MeSH
- buněčná diferenciace účinky léků MeSH
- buněčná smrt účinky léků MeSH
- cytokininy farmakologie terapeutické užití MeSH
- isochinoliny farmakologie MeSH
- kaspasa 3 metabolismus MeSH
- kaspasa 7 metabolismus MeSH
- kyselina glutamová toxicita MeSH
- kyslík metabolismus MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- neurony účinky léků MeSH
- neuroprotektivní látky farmakologie terapeutické užití MeSH
- oxidační stres účinky léků MeSH
- Parkinsonova nemoc farmakoterapie patologie MeSH
- regulátory růstu rostlin farmakologie MeSH
- superoxidy metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- acetylcystein MeSH
- cytokininy MeSH
- isochinoliny MeSH
- kaspasa 3 MeSH
- kaspasa 7 MeSH
- kyselina glutamová MeSH
- kyslík MeSH
- neuroprotektivní látky MeSH
- regulátory růstu rostlin MeSH
- salsolinol MeSH Prohlížeč
- superoxidy MeSH
Cancer remains one of the main causes of human mortality despite significant progress in its diagnostics and therapy achieved in the past decade. Massive hypomethylation of retrotransposons, in particular LINE-1, is considered a hallmark of most malignant transformations as it results in the reactivation of retroelements and subsequent genomic instability. Accumulating data on LINE-1 aberrant methylation in different tumor types indicates its significant role in cancer initiation and progression. However, direct evidence that LINE-1 activation can be used as a cancer biomarker is still limited. The objective of this review was to critically evaluate the published results regarding the diagnostic/prognostic potential of the LINE-1 methylation status in cancer. Our analysis indicates that LINE-1 hypomethylation is a promising candidate biomarker of cancer development, which, however, needs validation in both clinical and laboratory studies to confirm its applicability to different cancer types and/or stages. As LINE-1 is present in multiple cell-free copies in blood, it has advantages over single-copy genes regarding perspectives of using its methylation status as an epigenetic cancer biomarker for cell-free DNA liquid biopsy.
- Klíčová slova
- DNA methylation, LINE-1 (L1), cell-free DNA, epigenetic cancer biomarker,
- MeSH
- analýza přežití MeSH
- dlouhé rozptýlené jaderné elementy * MeSH
- epigeneze genetická MeSH
- lidé MeSH
- metylace DNA MeSH
- nádorové biomarkery krev genetika MeSH
- nádory diagnóza farmakoterapie genetika mortalita MeSH
- nestabilita genomu MeSH
- prognóza MeSH
- progrese nemoci MeSH
- protinádorové látky terapeutické užití MeSH
- regulace genové exprese u nádorů * MeSH
- signální transdukce MeSH
- tekutá biopsie MeSH
- transpozibilní elementy DNA * MeSH
- volné cirkulující nukleové kyseliny krev genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- nádorové biomarkery MeSH
- protinádorové látky MeSH
- transpozibilní elementy DNA * MeSH
- volné cirkulující nukleové kyseliny MeSH
- MeSH
- buněčné klony MeSH
- lidé MeSH
- nemocnice * statistika a číselné údaje MeSH
- rezistence na methicilin * MeSH
- stafylokokové infekce epidemiologie MeSH
- Staphylococcus aureus fyziologie MeSH
- surveillance populace * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika epidemiologie MeSH
- Klíčová slova
- Bcl-2, bortezomib, multiple myeloma, t(11;14), venetoclax,
- MeSH
- bicyklické sloučeniny heterocyklické aplikace a dávkování MeSH
- bortezomib aplikace a dávkování MeSH
- dexamethason aplikace a dávkování MeSH
- lidé středního věku MeSH
- lidé MeSH
- lidské chromozomy, pár 11 genetika MeSH
- lidské chromozomy, pár 14 genetika MeSH
- míra přežití MeSH
- mnohočetný myelom farmakoterapie genetika patologie MeSH
- následné studie MeSH
- prognóza MeSH
- protokoly protinádorové kombinované chemoterapie terapeutické užití MeSH
- retrospektivní studie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- sulfonamidy aplikace a dávkování MeSH
- translokace genetická * MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- dopisy MeSH
- Názvy látek
- bicyklické sloučeniny heterocyklické MeSH
- bortezomib MeSH
- dexamethason MeSH
- sulfonamidy MeSH
- venetoclax MeSH Prohlížeč
In Morocco, leishmaniases are a major public health problem due to their genetic diversity and geographical distribution. Cutaneous leishmaniasis (CL) is an infectious disease caused by various species of Leishmania and transmitted typically by bite of phlebotomine sand flies. This study identifies sand fly fauna in Ibaraghen village, province of Azilal, which is a focus of CL, by combination of morphological and molecular methods (sequencing of COI gene, MALDI-TOF MS protein profiling). Nested-kDNA PCR was used to detect and identify Leishmania species within potential vector species. 432 CDC light traps were placed at different heights above ground level at four capture sites during a whole year. Traps at 1.5 m above the ground yielded capture of sand flies almost double compared to above ground level (29.33%), while the collection reached 55.09% when the traps were placed 2.5 m above ground. A total of 2,830 sand flies were collected, 2,213 unfed specimens were morphologically identified, 990 males (44.73%) and 1,223 females (55.26%) of 13 species; ten Phlebotomus species and three Sergentomyia species. Six species were analysed by MALDI-TOF MS protein profiling (4 Phlebotomus and 2 Sergentomiya species), and their identification was confirmed by COI sequencing. 1,375 unfed females were screened for the presence of Leishmania by nested-kDNA PCR in pools, 11/30 pools of P. sergenti showing a single band of 750 bp corresponding to L. tropica. Our results confirm the role of P. sergenti as a proven vector in Azilal focus of cutaneous leishmaniasis; however, the relative abundance of other species known as vectors of Leishmania species emphasizes the risk of introduction of L. infantum and L. major in this province. For the first time in Morocco, a combined approach to identify sand flies by both morphology and molecular methods based on DNA barcoding and MALDI-TOF MS protein profiling was applied.
- Klíčová slova
- Morocco, cutaneous leishmaniasis, leishmania tropica, molecular screening, proteomic identification, sand fly,
- MeSH
- hmyz - vektory MeSH
- kinetoplastová DNA MeSH
- Leishmania * genetika MeSH
- leishmanióza kožní * epidemiologie veterinární MeSH
- Phlebotomus * MeSH
- Psychodidae * MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice veterinární MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Maroko epidemiologie MeSH
- Názvy látek
- kinetoplastová DNA MeSH
Carotenoids represent the first line of defence of photosystems against singlet oxygen (1O2) toxicity, because of their capacity to quench the chlorophyll triplet state (3Chl) through a physical mechanism based on the transfer of triplet excitation (triplet-triplet energy transfer, TTET). In previous works, we showed that the antenna LHCII is characterised by a robust photoprotective mechanism, able to adapt to the removal of individual chlorophylls while maintaining a remarkable capacity for 3Chl quenching. In this work, we investigated the effects on this quenching induced in LHCII by the replacement of the lutein bound at the L1 site with violaxanthin and zeaxanthin. We studied LHCII isolated from the Arabidopsis thaliana mutants lut2-in which lutein is replaced by violaxanthin-and lut2 npq2, in which all xanthophylls are replaced constitutively by zeaxanthin. We characterised the photophysics of these systems via optically detected magnetic resonance (ODMR) and time-resolved electron paramagnetic resonance (TR-EPR). We concluded that, in LHCII, lutein-binding sites have conserved characteristics, and ensure efficient TTET regardless of the identity of the carotenoid accommodated.
- Klíčová slova
- LHCII, ODMR, TR-EPR, TTET, carotenoid, light-harvesting complex II, triplet state,
- MeSH
- Arabidopsis * metabolismus MeSH
- chlorofyl metabolismus MeSH
- fotosystém II (proteinový komplex) metabolismus MeSH
- karotenoidy metabolismus MeSH
- lutein * MeSH
- přenos energie MeSH
- světlosběrné proteinové komplexy metabolismus MeSH
- xanthofyly chemie MeSH
- zeaxanthiny metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- chlorofyl MeSH
- fotosystém II (proteinový komplex) MeSH
- karotenoidy MeSH
- lutein * MeSH
- světlosběrné proteinové komplexy MeSH
- violaxanthin MeSH Prohlížeč
- xanthofyly MeSH
- zeaxanthiny MeSH
Of the two human herpesvirus 6 (HHV-6) species, human herpesvirus 6B (HHV-6B) encephalitis is an important cause of morbidity and mortality after allogeneic hematopoietic stem cell transplant. Guidelines for the management of HHV-6 infections in patients with hematologic malignancies or post-transplant were prepared a decade ago but there have been no other guidelines since then despite significant advances in the understanding of HHV-6 encephalitis, its therapy, and other aspects of HHV-6 disease in this patient population. Revised guidelines prepared at the 2017 European Conference on Infections in Leukaemia covering diagnosis, preventative strategies and management of HHV-6 disease are now presented.
- MeSH
- antivirové látky farmakologie terapeutické užití MeSH
- hematologické nádory komplikace diagnóza terapie MeSH
- imunokompromitovaný pacient MeSH
- infekce roseoloviry diagnóza etiologie terapie MeSH
- kombinovaná terapie MeSH
- lidé MeSH
- lidský herpesvirus 6 * MeSH
- nemoc štěpu proti hostiteli etiologie MeSH
- směrnice pro lékařskou praxi jako téma * MeSH
- transplantace hematopoetických kmenových buněk škodlivé účinky metody MeSH
- virová transformace buněk MeSH
- výsledek terapie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Geografické názvy
- Evropa MeSH
- Názvy látek
- antivirové látky MeSH