UNLABELLED: The need for suitable selective cultivation media for the isolation of Bifidobacterium spp. continues to be a real concern in the field of intestinal microbiology. Isolation of bifidobacteria from human and animal faecal samples using selective agar plating may be problematic especially in samples with increased clostridial counts than bifidobacterial counts. Due to the absence of anticlostridial agents in existing selective media, clostridia can displace bifidobacteria resulting in incorrect estimation of their counts. Therefore, we supplemented the existing selective medium 'modified Wilkins Chalgren agar with mupirocin' (MWM) with 90 mg l(-1) of 8-hydroxyquinoline (8HQ), which was recently proved to act selectively against clostridia. The newly composed 'modified Wilkins-Chalgren agar with 8HQ' (MWMQ) was tested on pure bifidobacterial and clostridial strains, their mixtures, and using faecal samples of mammalian origin; its selectivity was evaluated by genus-specific identification of isolates. The results demonstrated that the presence of 8HQ in this agar eliminated the growth of nonbifidobacterial strains on MWMQ compared to that on MWM, whereas the recovery of bifidobacterial counts was at satisfactory levels. In conclusion, MWMQ could be recommended for bifidobacterial isolation from human and animal faeces especially when bifidobacteria are not numerically dominant and there are chances of clostridial contamination. SIGNIFICANCE AND IMPACT OF THE STUDY: Routine isolation of bifidobacteria from mammalian faeces does not use a reliable selective agar with an anticlostridial agent. Overgrowth of clostridia may result in incorrect estimation of bifidobacterial counts. Thus, in order to improve the selectivity of existing media for bifidobacterial isolation, we chose the modified Wilkins-Chalgren agar with mupirocin and supplemented it with 8-hydroxyquinoline (8HQ), a molecule that shows anticlostridial activity without affecting the growth of bifidobacteria. This newly composed medium showed enhanced selectivity and specificity compared to the original medium and therefore, can be recommended for the isolation of bifidobacteria from mammal faeces.

• Klíčová slova
• 8-quinolinol, Bifidobacterium, Clostridium, intestinal microbiota, isolation, selective agar,
• MeSH
• agar farmakologie   MeSH
• bakteriální nálož účinky léků   MeSH
• Bifidobacterium růst a vývoj   izolace a purifikace   MeSH
• Clostridium účinky léků   růst a vývoj   MeSH
• feces mikrobiologie   MeSH
• kultivační média farmakologie   MeSH
• lidé MeSH
• mupirocin farmakologie   MeSH
• oxychinolin farmakologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• agar MeSH
• kultivační média MeSH
• mupirocin MeSH
• oxychinolin MeSH

The transcriptional activity of an integrated retroviral copy strongly depends on the adjacent host-cell DNA at the site of integration. Transcribed DNA loci as well as cis-acting sequences like enhancers or CpG islands usually permit expression of nearby integrated proviruses. In contrast, proviruses residing close to cellular silencers tend to transcriptional silencing and CpG methylation. Little is known, however, about the influence of provirus integration on the target sequence in the host genome. Here, we report interesting features of a simplified Rous sarcoma virus integrated into a non-transcribed hypermethylated DNA sequence in the Syrian hamster genome. After integration, CpG methylation of this sequence has been lost almost completely and hypomethylated DNA permits proviral transcription and hamster cell transformation by the proviral v-src oncogene. This, however, is not a stable state, and non-transformed revertants bearing transcriptionally silenced proviruses segregate with a high rate. The provirus silencing is followed by DNA methylation of both provirus regulatory regions and adjacent cellular sequences. This CpG methylation is very dense and resistant to the demethylation effects of 5-aza-2(')-deoxycytidine and/or trichostatin A. Our description exemplifies the capacity of retroviruses/retroviral vectors to overcome, at least transiently, negative position effects of DNA methylation at the site of integration.

• MeSH
• agar farmakologie   MeSH
• azacytidin analogy a deriváty   farmakologie   MeSH
• buněčné linie MeSH
• CpG ostrůvky MeSH
• decitabin MeSH
• genetická transkripce MeSH
• geny src genetika   MeSH
• histondeacetylasy metabolismus   MeSH
• inhibitory enzymů farmakologie   MeSH
• inhibitory syntézy proteinů farmakologie   MeSH
• integrace viru * MeSH
• koncové repetice MeSH
• křečci praví MeSH
• křeček rodu Mesocricetus MeSH
• kyseliny hydroxamové farmakologie   MeSH
• metylace DNA * MeSH
• modely genetické MeSH
• molekulární sekvence - údaje MeSH
• nádorové buněčné linie MeSH
• Retroviridae genetika   MeSH
• siřičitany farmakologie   MeSH
• zvířata MeSH
• Check Tag
• křečci praví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• agar MeSH
• azacytidin MeSH
• decitabin MeSH
• histondeacetylasy MeSH
• inhibitory enzymů MeSH
• inhibitory syntézy proteinů MeSH
• kyseliny hydroxamové MeSH
• siřičitany MeSH
• trichostatin A MeSH Prohlížeč

The possibilities of cultivating murine bone marrow in semisolid agar and in methyl cellulose were investigated. The proliferative capacity of the haemopoietic CFU-C stem cells were demonstrated. The growth of CFU-C in fresh murine bone marrow and murine marrow short-term preserved at -75 degrees C was compared. The content of cells capable of proliferation was lower and the onset of colony formation was delayed in preserved bone marrow. Procedures appropriate for routine work were employed for evaluating haemopoietic colonies.

• MeSH
• agar farmakologie   MeSH
• analýza kolonii tvořících jednotek * MeSH
• buněčná diferenciace * MeSH
• časové faktory MeSH
• kultivační média MeSH
• kultivované buňky MeSH
• methylcelulosa farmakologie   MeSH
• myši MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• agar MeSH
• kultivační média MeSH
• methylcelulosa MeSH

We have investigated the effect of conditioned medium derived from cultures of human placental tissue from different phases of pregnancy on in vitro growth of human and mouse granulocyte-macrophage colony forming cells in semisolid agar. We have confirmed that the colony-stimulating activity of human placental conditioned (normal delivery) medium was equivalent to the activity of peripheral blood leucocyte underlayers when medium was added at a 5%-20% concentration to the semisolid agar. Placentas from the 12th amd 10th week of gestation were found not convenient for preparation of medium with high CSA; the activity of media prepared from their cultures was not significantly higher than the autostimulating activity of bone marrow alone. Human placental conditioned medium proved inconvenient for cultures of mouse GM-CFC in semisolid agar containing foetal calf serum.

• MeSH
• agar farmakologie   MeSH
• faktory stimulující kolonie farmakologie   MeSH
• gestační stáří MeSH
• granulocyty fyziologie   MeSH
• hematopoetické kmenové buňky účinky léků   MeSH
• kultivační média MeSH
• kultivované buňky MeSH
• lidé MeSH
• makrofágy fyziologie   MeSH
• myši MeSH
• placenta cytologie   MeSH
• těhotenství MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• agar MeSH
• faktory stimulující kolonie MeSH
• kultivační média MeSH

• MeSH
• agar farmakologie   MeSH
• arboviry účinky léků   MeSH
• cytopatogenní efekt virový MeSH
• heparin farmakologie   MeSH
• kuřecí embryo MeSH
• lidé MeSH
• techniky in vitro MeSH
• těhotenství MeSH
• zvířata MeSH
• Check Tag
• kuřecí embryo MeSH
• lidé MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• agar MeSH
• heparin MeSH