Nejvíce citovaný článek - PubMed ID 8157581
Understanding the intricate dynamics of sediment-mediated microbial interactions and their impact on plant tissue preservation is crucial for unraveling the complexities of leaf decay and preservation processes. To elucidate the earliest stages of leaf preservation, a series of decay experiments was carried out for three months on Nymphaea water lily leaves in aquariums with pond water and one of three distinctly different, sterilized, fine-grained substrates-commercially purchased kaolinite clay or fine sand, or natural pond mud. One aquarium contained only pond water as a control. We use 16S and ITS rRNA gene amplicon sequencing to identify and characterize the complex composition of the bacterial and fungal communities on leaves. Our results reveal that the pond mud substrate produces a unique community composition in the biofilms compared to other substrates. The mud substrate significantly influences microbial communities, as shown by the correlation between high concentrations of minerals in the water and bacterial abundance. Furthermore, more biofilm formers are observed on the leaves exposed to mud after two months, contrasting with declines on other substrates. The mud substrate also enhanced leaf tissue preservation compared to the other sediment types, providing insight into the role of sediment and biofilms in fossilization processes. Notably, leaves on kaolinite clay have the fewest biofilm formers by the end of the experiment. We also identify key biofilm-forming microbes associated with each substrate. The organic-rich mud substrate emerges as a hotspot for biofilm formers, showing that it promotes biofilm formation on leaves and may increase the preservation potential of leaves better than other substrates. The mud's chemical composition, rich in minerals such as silica, iron, aluminum, and phosphate, may slow or suspend decay and facilitate biomineralization, thus paving the way toward leaf preservation. Our study bridges the information gap between biofilms observed on modern leaves and the mineral encrustation on fossil leaves by analyzing the microbial response in biofilms to substrate types in which fossil leaves are commonly found.
To assess the long-term anthropogenic load of the Bílina River (Czech Republic), the concentrations of heavy metals and specific organic compounds in different river ecosystem matrices (water, biofilms, and sediments) were determined. Although the current concentrations of pollutants in surface water are low, frequently below the limits of the quantitative analytical methods used, the river ecosystem is still heavily loaded by anthropogenic pollution, mainly from the chemical and mining industries. This was demonstrated by analyzing biofilms and sediments. These matrices are more accurate representatives of the actual situation in the river and do not depend on hydrological conditions or random variability in water quality. The results indicate that the middle and the lower parts of the river are heavily polluted by mercury, arsenic, vanadium, polychlorinated biphenyls, hexachlorobenzene, and dichloro-diphenyl-trichloroethane. As a tributary of the Elbe River, the Bílina River represents a significant risk for the development of quality in this major European river.
- MeSH
- biofilmy * MeSH
- chemické látky znečišťující vodu analýza MeSH
- geologické sedimenty chemie MeSH
- organické látky analýza MeSH
- sběr dat MeSH
- sladká voda chemie MeSH
- těžké kovy analýza MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
- Názvy látek
- chemické látky znečišťující vodu MeSH
- organické látky MeSH
- těžké kovy MeSH
Dental caries is a highly prevalent multifactorial disease that can result in serious health impairment. It was shown that oral bacteria play a significant role in caries development. Point-of-care (POC) salivary microbial tests for detection of cariogenic species have been investigated as a potential tool for caries risk assessment. This review aims to evaluate clinical relevance of these tests in the light of recent scientific evidence. Methodology involved PubMed search using key words salivary microbial tests, cariogenic bacteria and caries risk prediction. Articles obtained by the search were cross-referenced to obtain further sources. Specificity and negative-predictive value of these tests are higher than their sensitivity and positive value. Predictive power of the POC salivary microbial tests as a single predictor is generally weak, although it increases when included in multifactorial models for caries prediction. Literature findings support the use of these tests for screening of at-risk individuals in a population of young preschool children without visible caries and for motivation of subjects on individual level. POC salivary microbial tests are simple and inexpensive and, therefore, may be advantageous from public health perspective.
- MeSH
- Bacteria klasifikace izolace a purifikace patogenita MeSH
- bakteriální infekce komplikace diagnóza mikrobiologie MeSH
- bakteriologické techniky metody MeSH
- lidé MeSH
- sliny mikrobiologie MeSH
- vyšetření u lůžka * MeSH
- zubní kaz mikrobiologie prevence a kontrola MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
