scholarly journals Methyl Potassium Siliconate and Siloxane Inhibit the Formation of Multispecies Biofilms on Ceramic Roof Tiles: Efficiency and Comparison of Two Common Water Repellents

2021 ◽  
Vol 9 (2) ◽  
pp. 394
Author(s):  
Mattea Romani ◽  
Claire Carrion ◽  
Frédéric Fernandez ◽  
Philippe Lebaron ◽  
Raphaël Lami
Keyword(s):  
Building Materials ◽  
Microbial Colonization ◽  
Water Repellent ◽  
Colonization Patterns ◽  
Biofilm Development ◽  
Multispecies Biofilms ◽  
Water Repellents

Ceramic roof tiles are widespread marketed building materials, rapidly colonized by microorganisms that form multispecies biofilms on their surface and play crucial roles in biodeterioration processes. Coating tiles with water repellents is a pervasive industrial strategy employed to prevent liquid water penetration and slow biodeterioration. Very few studies have examined the links between the characteristics of water-repellent coatings and biofilm colonization patterns. Our work aims to compare the effects of coating tiles with two common water repellents (siliconate and siloxane) on the growth of colonizing microbes. We combined in situ exposure of tiles for over six years and macroscopic and microscopic observations with in vitro biotests, relying on the use of algal and fungal models. Our data showed that (1) tiles coated with water repellents were macroscopically less colonized by lichens (2) a significant fungal biofilm development at the microscopic scale (3) water repellents had very contrasting effects on our model strains. These data reinforce the great interest for industry to conduct more studies linking the nature of the water repellents with the composition of colonizing multispecies biofilms. The long-term objective is to improve the available water repellents and better adapt their selection to the nature of microbial colonization.

scholarly journals Study of Surface Structure Changes for Selected Ceramics Used in the CAD/CAM System on the Degree of Microbial Colonization, In Vitro Tests

2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Maciej Dobrzynski ◽  
Magdalena Pajaczkowska ◽  
Joanna Nowicka ◽  
Aleksander Jaworski ◽  
Piotr Kosior ◽  
...  
Keyword(s):  
Dental Materials ◽  
Lactobacillus Rhamnosus ◽  
Microbial Colonization ◽  
In Vitro Tests ◽  
Adhesive Properties ◽  
Structure Changes ◽  
Cad Cam ◽  
Biofilm Development ◽  
Made In

In the article has been presented an analysis of susceptibility of selected dental materials, made in the CAD/CAM technology. The morphology and structural properties of selected dental materials and their composites were determined by using XRPD (X-ray powder diffraction) techniques, as well as the IR (infrared) spectroscopy. Moreover, an adhesion as well as development of biofilm by oral microorganisms has been studied. It has been shown that a degree of the biofilm development on the tested dental materials depended on microorganism genus and species. Streptococcus mutans has demonstrated the best adhesion to the tested materials in comparison with Candida albicans and Lactobacillus rhamnosus. However, the sintered materials such as IPS e.max® and the polished IPS e.max® have showed the best “anti-adhesive properties” in relation to S. mutans and L. rhamnosus that have not formed the biofilm on the polished IPS e.max® sample. Furthermore, S. mutans have not formed the biofilm on both surfaces. On the contrary to S. mutans and L. rhamnosus, C. albicans has demonstrated the adhesive properties in relation to the above-mentioned surfaces. Moreover, in contrast to S. mutans and C. albicans, L. rhamnosus has not formed the biofilm on the polished IPS Empress material.

In situ generation of human brain organoids on a micropillar array

Lab on a Chip ◽  
2017 ◽  
Vol 17 (17) ◽  
pp. 2941-2950 ◽  
Author(s):  
Yujuan Zhu ◽  
Li Wang ◽  
Hao Yu ◽  
Fangchao Yin ◽  
Yaqing Wang ◽  
...  
Keyword(s):  
Stem Cells ◽  
Human Brain ◽  
Pluripotent Stem Cells ◽  
3D Culture ◽  
In Situ Generation ◽  
Induced Pluripotent ◽  
High Throughput Manner

We present a simple and high throughput manner to generate brain organoids in situ from human induced pluripotent stem cells on micropillar arrays and to investigate long-term brain organogenesis in 3D culture in vitro.

Adaptation to calcium deprivation in the rat: effects of parathyroidectomy.

1977 ◽  
Vol 232 (3) ◽  
pp. E336
Author(s):  
J T Pento ◽  
L C Waite ◽  
P J Tracy ◽  
A D Kenny
Keyword(s):  
Adaptive Response ◽  
Calcium Transport ◽  
Parathyroid Tissue ◽  
Adaptation Period ◽  
Short Term ◽  
High Calcium

The role of parathyroid hormone (PTH) in the adaptive response in gut calcium transport to calcium deprivation has been studied in the rat using both the in vitro everted duodenal sac and the in situ ligated duodenal segment technique. Intact or parathyroidectomized (PTX) young rats were placed on a low calcium (0.01%) diet for 7-, 14-, or 21-day adaptation periods and compared with control rats maintained on a high calcium (1.5%) diet. Prior PTX (3 days before the start of the adaptation period) abolished the adaptive response (enhanced calcium transport) induced by calcium deprivation for a 7-day adaptation period, but did not abolish a response after a 21-day period. A 14-day adaptation period gave equivocal results. It is concluded that PTH appears to be necessary for short-term (7-day) adaptation, but not for long-term (21-day) adaptation to calcium deprivation. However, if accessory parathyroid tissue is present, the data could be interpreted differently: the essentiality of PTH for the adaptive response might be independent of the length of the adaptation period. The data also contribute to a possible resolution of the controversy concerning the involvement of PTH in the regulation of intestinal calcium transport in the rat.

scholarly journals Long-term conservation of potato genetic resources: Methods and status of conservation

2019 ◽  
pp. 717-725
Author(s):  
Jane Muthoni ◽  
Hussein Shimelis ◽  
Rob Melis
Keyword(s):  
Genetic Resources ◽  
Slow Growth ◽  
Plant Genetic Resources ◽  
Ex Situ ◽  
Growth Media ◽  
Medium Term ◽  
Natural Habitats

Plant genetic resources (PGRs) play an important role in agriculture, environment protection, cultural property and trade; they need to be conserved. There are two fundamental approaches for the conservation of PGRs: in situ and ex situ. In situ conservation is the conservation of ecosystems and natural habitats and the maintenance and recovery of viable populations of species in their natural surroundings. Ex situ preservation is the storage of seeds or plant materials under artificial conditions to maintain their long term viability and availability for use. Genebanks employ seed storage, field collections of living plants and in vitro storage (tissue culture or cryopreservation) for ex situ preservation of PGR. Storage of orthodox seeds, which are tolerant to low moisture content and low temperatures at appropriate temperature and humidity, is the most convenient ex situ conservation method. Plants that produce recalcitrant seeds or non-viable seeds are conserved in field genebanks as well as in-vitro in slow growth media for short-to-medium term and cryopreservation in liquid nitrogen at -1960C for long-term periods. Cryopreservation is very expensive and needs trained personnel; this could explain why this method is rarely used for conservation of plant genetic resources in most developing countries. Potato tubers are bulky and highly perishable; the crop is generally conserved as clones either in field genebanks (with annual replanting), in-vitro conservation in slow growth media for short-to-medium term and cryopreservation for long term. Field genebanks are expensive to maintain and the crop is exposed to many dangers; hence, cryopreservation is the only feasible method for long term conservation. However, given the high cost of cryopreservation, long-term conservation of potato genetic resources is poorly developed in most resource-poor countries leading to high rates of genetic erosion. This paper looks into the various methods that that can be applied to conserve potato genetic resources and the status of conservation of potatoes in major genebanks and some countries.

The Primary Investigation on Biological Effect of Mesoporous Bioactive Glass In Vivo

2013 ◽  
Vol 750-752 ◽  
pp. 1651-1655
Author(s):  
Bai Yan Sui ◽  
Cheng Tie Wu ◽  
Jiao Sun
Keyword(s):  
Bioactive Glass ◽  
Biological Effect ◽  
Degradation Products ◽  
Long Term Effect ◽  
Liver And Kidney ◽  
Mesoporous Bioactive Glass

Mesoporous bioactive glass (MBG) has superior bioactivity and degradation than non-mesoporous bioactive glass (BG) in vitro. But the biological effect of MBG in vivo is still unknown. In this study, MBG powders with 20μm were implanted into the femoral condyles in SD rats. BG powders with 20μm were used as a control. The local degradation and osteogenesis were observed at 1 week and 4 weeks after implantation, and the systemic toxicity of the degradation products were also evaluated simultaneously. The results revealed MBG powders had the faster rate of degradation and better osteogenesis effect than BG powders at 4 weeks, although the most of material still remained in situ. Histopathological analyses indicated the degradation products did not have any damage to major organs such as liver and kidney. In conclusion, this preliminary study demonstrated that MBG powders have more excellent biological effect at 4 weeks than that of BG in vivo. However the long-term effect needs to be confirmed.

scholarly journals Apricot breeding for tolerance to Plum pox potyvirus in Nikita Botanical Gardens

2020 ◽  
pp. 5-13
Author(s):  
V. M. Gorina ◽  
I. V. Mitrofanova ◽  
O. V. Mitrofanova ◽  
N. P. Lesnikova-Sedoshenko ◽  
S. N. Chirkov
Keyword(s):  
Molecular Genetic ◽  
Botanical Garden ◽  
Commercial Cultivation ◽  
Open Ground ◽  
Hybrid Seeds ◽  
Stable Yield ◽  
Academy Of Sciences

For the fi rst time, the results of studying of varieties and breeding forms of apricot in the gene pool collection of the Nikita Botanical Garden – the National Scientifi c Center of the Russian Academy of Sciences (NBS – NSC) (Yalta, Crimea) on the tolerance to the plum Sharka disease – Plum pox potyvirus (PPV), are presented in the article. The collection includes varieties from diff erent ecological and geographical groups that give us the possibility to present an objective comparative assessment of their susceptibility to phytopathogens. Based on long-term monitoring of the apricot orchards on PPV susceptibility in the collection of NBG-NSC, single aff ected plants were discovered and exterminated. Molecular genetic approaches to apricot breeding for tolerance were demonstrated and PPV tolerant genotypes were selected. According to the results of the research, hybridization was carried out. During the entire period of the research, in order to create genotypes tolerant to PPV, 28 738 fl owers were pollinated and 2 908 hybrid seeds were obtained from which plants were grown. Under in situ and in vitro conditions, new breeding forms tolerant to PPV were obtained. The prospect of biotechnological methods usage for inducing the development of hybrid apricot embryos was shown. The conditions for their culture (trophic, hormonal, and physical) were determined, viable seedlings and plants were obtained in vitro and planted for further adaptation ex vitro and to the open ground. New created plants were evaluated and breeding forms were selected, characterized by tolerance to PPV, good fruit quality and high stable yield. Based on the comprehensive studies, two breeding forms of apricot (‘97 -11 ’and ’97-17’) tolerant to PPV and promising for breeding and commercial cultivation were identifi ed.

scholarly journals Primary Extracellular Matrix Enables Long-Term Cultivation of Human Tumor Oral Mucosa Models

2020 ◽  
Vol 8 ◽  
Author(s):  
Leonie Gronbach ◽  
Philipp Jurmeister ◽  
Monika Schäfer-Korting ◽  
Ulrich Keilholz ◽  
Ingeborg Tinhofer ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Oral Mucosa ◽  
Hypoxia Inducible Factor ◽  
Human Tumor ◽  
Patient Specific ◽  
Long Term Effects ◽  
Tumor Models

3D tumor models clearly outperform 2D cell cultures in recapitulating tissue architecture and drug response. However, their potential in understanding treatment efficacy and resistance development should be better exploited if also long-term effects of treatment could be assessed in vitro. The main disadvantages of the matrices commonly used for in vitro culture are their limited cultivation time and the low comparability with patient-specific matrix properties. Extended cultivation periods are feasible when primary human cells produce the extracellular matrix in situ. Herein, we adapted the hyalograft-3D approach from reconstructed human skin to normal and tumor oral mucosa models and compared the results to bovine collagen-based models. The hyalograft models showed similar morphology and cell proliferation after 7 weeks compared to collagen-based models after 2 weeks of cultivation. Tumor thickness and VEGF expression increased in hyalograft-based tumor models, whereas expression of laminin-332, tenascin C, and hypoxia-inducible factor 1α was lower than in collagen-based models. Taken together, the in situ produced extracellular matrix better confined tumor invasion in the first part of the cultivation period, with continuous tumor proliferation and increasing invasion later on. This proof-of-concept study showed the successful transfer of the hyalograft approach to tumor oral mucosa models and lays the foundation for the assessment of long-term drug treatment effects. Moreover, the use of an animal-derived extracellular matrix is avoided.

scholarly journals Survival of and In Situ Gene Expression by Vibrio vulnificus at Varying Salinities in Estuarine Environments

2007 ◽  
Vol 74 (1) ◽  
pp. 182-187 ◽  
Author(s):  
Melissa K. Jones ◽  
Elizabeth Warner ◽  
James D. Oliver
Keyword(s):  
Gene Expression ◽  
Vibrio Vulnificus ◽  
Natural Habitat ◽  
Term Survival ◽  
Long Term Survival ◽  
Wide Range ◽  
Opportunistic Human Pathogen

ABSTRACT The opportunistic human pathogen Vibrio vulnificus survives in a wide range of ecological environments, which demonstrates its ability to adapt to highly variable conditions. Survival and gene expression under various conditions have been extensively studied in vitro; however, little work has been done to evaluate this bacterium in its natural habitat. Therefore, this study monitored the long-term survival of V. vulnificus in situ and simultaneously evaluated the expression of stress (rpoS, relA, hfq, and groEL) and putative virulence (vvpE, smcR, viuB, and trkA) genes at estuarine sites of varying salinity. Additionally, the survival and gene expression of an rpoS and an oxyR mutant were examined under the same conditions. Differences between the sampling sites in the long-term survival of any strain were not seen. However, differences were seen in the expression of viuB, trkA, and relA but our findings differed from what has been previously shown in vitro. These results also routinely demonstrated that genes required for survival under in vitro stress or host conditions are not necessarily required for survival in the water column. Overall, this study highlights the need for further in situ evaluation of this bacterium in order to gain a true understanding of its ecology and how it relates to its natural habitat.

A toddler SHIME® model to study microbiota of young children

2020 ◽  
Vol 367 (16) ◽  
Author(s):  
Pauline Bondue ◽  
Sarah Lebrun ◽  
Bernard Taminiau ◽  
Nadia Everaert ◽  
Gisele LaPointe ◽  
...  
Keyword(s):  
Young Children ◽  
Short Chain Fatty Acid ◽  
Amplicon Sequencing ◽  
Bacterial Populations ◽  
16S Rrna Amplicon Sequencing ◽  
Biofilm Development ◽  
Stabilization Period ◽  
Gut Microbiota Composition

ABSTRACT The ‘first 1000 days of life’ determine the gut microbiota composition and can have long-term health consequences. In this study, the simulator of the human intestinal microbial ecosystem (SHIME®) model, which represents the main functional sections of the digestive tract, was chosen to study the microbiota of young children. The aim of this study was to reproduce the digestive process of toddlers and their specific colonic environment. The ascending, transverse and descending colons of SHIME® model were inoculated with feces from three donors aged between 1 and 2 years-old, in three separate runs. For each run, samples from colon vessels were collected at days 14, 21 and 28 after microbiota stabilization period. Short chain fatty acid concentrations determined by HPLC showed that microbiota obtained in SHIME® model shared characteristics between adults and infants. In addition, microbial diversity and bacterial populations determined by 16S rRNA amplicon sequencing were specific to each colon vessel. In conclusion, the SHIME® model developed in this study seemed well adapted to evaluate prebiotic and probiotic impact on the specific microbiota of toddlers, or medicine and endocrine disruptor metabolism. Moreover, this study is the first to highlight some biofilm development in in vitro gastrointestinal modelling systems.

Effects of Bisphosphonate on Long-Term Culture of Cartilage Allografts

2013 ◽  
Author(s):  
Yilu Zhou ◽  
Lauren Resutek ◽  
Liyun Wang ◽  
X. Lucas Lu
Keyword(s):  
Medial Meniscus ◽  
Biomechanical Properties ◽  
Culture Conditions ◽  
Protective Mechanisms ◽  
Post Traumatic ◽  
Biochemical Mechanisms ◽  
Altered Metabolism

Zoledronic acid (ZA), an FDA approved bisphosphonate (BP) medicine, is widely used for the treatment of osteoclast-related bone loss diseases [1]. Our previous study has found that systemic administration of ZA could dramatically suppress the development of post-traumatic osteoarthritis (PTOA) in the DMM (destabilization of the medial meniscus) mouse model, a model recapitulating the altered joint loading associated with PTOA [2]. This finding is consistent with a few similar studies using different animal models [3]. However, little is known about the cellular and biochemical mechanisms of BP mediated chondro-protection in PTOA pathogenesis. Studies have shown that PTOA often initiates from the apoptosis and altered metabolism of cartilage chondrocytes. In this study, we will investigate the direct effects of ZA on the metabolisms of chondrocytes using long-term in vitro culture of cartilage allografts. As one of the earliest responses of chondrocytes to mechanical stimulation, intracellular calcium ([Ca 2+] i) signaling is the upstream of numerous mechanotransduction pathways [4]. We hypothesize that the chondro-protective mechanisms of ZA could be represented by the characteristics of [Ca 2+] i signaling of in situ chondrocytes. Our specific aims were to: (i) compare the in situ spontaneous [Ca 2+] i responses of chondrocytes cultured in non-ZA and ZA supplemented environments, and (ii) compare the biomechanical properties of cartilage allografts under the two culture conditions.

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