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Parasites & Vectors Sep 2012The Natural History Museum (NHM) is developing a repository for schistosomiasis-related material, the Schistosomiasis Collection at NHM (SCAN) as part of its existing...
The Natural History Museum (NHM) is developing a repository for schistosomiasis-related material, the Schistosomiasis Collection at NHM (SCAN) as part of its existing Wolfson Wellcome Biomedical Laboratory (WWBL). This is timely because a major research and evaluation effort to understand control and move towards elimination of schistosomiasis in Africa has been initiated by the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), resulting in the collection of many important biological samples, including larval schistosomes and snails. SCAN will collaborate with a number of research groups and control teams and the repository will acquire samples relevant to both immediate and future research interest. The samples collected through ongoing research and field activities, WWBL's existing collections, and other acquisitions will be maintained over the long term and made available to the global research community for approved research purposes. Goals include: ·Consolidation of the existing NHM schistosome and snail collections and transfer of specimens into suitable long-term storage systems for DNA retrieval, ·Long-term and stable storage of specimens collected as part of on going field programmes initially in Africa especially relating to the SCORE research programmes, ·Provision of access to snail and schistosome collections for approved research activities.
Topics: Animals; Biological Specimen Banks; Biomedical Research; Museums; Natural History; Preservation, Biological; Schistosoma; Snails; United Kingdom
PubMed: 22943137
DOI: 10.1186/1756-3305-5-185 -
Nature Communications Jan 2019In vitro models incorporating the complexity and function of adult human tissues are highly desired for translational research. Whilst vital slices of human myocardium...
In vitro models incorporating the complexity and function of adult human tissues are highly desired for translational research. Whilst vital slices of human myocardium approach these demands, their rapid degeneration in tissue culture precludes long-term experimentation. Here, we report preservation of structure and performance of human myocardium under conditions of physiological preload, compliance, and continuous excitation. In biomimetic culture, tissue slices prepared from explanted failing human hearts attain a stable state of contractility that can be monitored for up to 4 months or 2000000 beats in vitro. Cultured myocardium undergoes particular alterations in biomechanics, structure, and mRNA expression. The suitability of the model for drug safety evaluation is exemplified by repeated assessment of refractory period that permits sensitive analysis of repolarization impairment induced by the multimodal hERG-inhibitor pentamidine. Biomimetic tissue culture will provide new opportunities to study drug targets, gene functions, and cellular plasticity in adult human myocardium.
Topics: Adult; Biomechanical Phenomena; Electric Stimulation; Gene Expression; Heart; Humans; Myocardial Contraction; Myocardium; Preservation, Biological; Time Factors; Tissue Culture Techniques
PubMed: 30631059
DOI: 10.1038/s41467-018-08003-1 -
PloS One 2022Organic molecules preserved in fossils provide a wealth of new information about ancient life. The discovery of almost unaltered complex organic molecules in...
Organic molecules preserved in fossils provide a wealth of new information about ancient life. The discovery of almost unaltered complex organic molecules in well-preserved fossils raise the question of how common such occurrences are in the fossil record, how to differentiate between endogenous and exogenous sources for the organic matter and what promotes such preservation. The aim of this study was the in-situ analysis of a well-preserved vertebrate fossil from 48 Ma Eocene sediments in the Messel pit, Germany for preservation of complex biomolecules. The fossil was characterized using a variety of techniques including time-of-flight secondary ion mass spectrometry (ToF-SIMS), scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM/EDX), x-ray diffraction (XRD) and Raman spectroscopy. A suite of organic molecules was detected, including porphyrins, which given the context of the detected signal are most probably diagenetically altered heme originating from the fossil though a microbial contribution cannot be completely ruled out. Diagenetic changes to the porphyrin structure were observed that included the exchange of the central iron by nickel. Further analyses on the geochemistry of the fossil and surrounding sediments showed presence of pyrite and aluminosilicates, most likely clay. In addition, a carbonate and calcium phosphate dominated crust has formed around the fossil. This suggests that several different processes are involved in the preservation of the fossil and the organic molecules associated with it. Similar processes seem to have also been involved in preservation of heme in fossils from other localities.
Topics: Animals; Fossils; Heme; Porphyrins; Preservation, Biological; Vertebrates
PubMed: 35767560
DOI: 10.1371/journal.pone.0269568 -
PloS One 2020Preservation of blood plasma in the dried state would facilitate long-term storage and transport at ambient temperatures, without the need of to use liquid nitrogen...
Preservation of blood plasma in the dried state would facilitate long-term storage and transport at ambient temperatures, without the need of to use liquid nitrogen tanks or freezers. The aim of this study was to investigate the feasibility of dry preservation of human plasma, using sugars as lyoprotectants, and evaluate macromolecular stability of plasma components during storage. Blood plasma from healthy donors was freeze dried using 0-10% glucose, sucrose, or trehalose, and stored at various temperatures. Differential scanning calorimetry was used to measure the glass transition temperatures of freeze-dried samples. Protein aggregation, the overall protein secondary structure, and oxidative damage were studied under different storage conditions. Differential scanning calorimetry measurements showed that plasma freeze-dried with glucose, sucrose and trehalose have glass transition temperatures of respectively 72±3.4°C, 46±11°C, 15±2.4°C. It was found that sugars diminish freeze-drying induced protein aggregation in a dose-dependent manner, and that a 10% (w/v) sugar concentration almost entirely prevents protein aggregation. Protein aggregation after rehydration coincided with relatively high contents of β-sheet structures in the dried state. Trehalose reduced the rate of protein aggregation during storage at elevated temperatures, and plasma that is freeze- dried plasma with trehalose showed a reduced accumulation of reactive oxygen species and protein oxidation products during storage. In conclusion, freeze-drying plasma with trehalose provides an attractive alternative to traditional cryogenic preservation.
Topics: Blood Proteins; Drug Stability; Drug Storage; Freeze Drying; Humans; Plasma; Preservation, Biological; Preservatives, Pharmaceutical; Protein Aggregates; Protein Conformation, beta-Strand; Protein Stability; Transition Temperature; Trehalose; Vitrification
PubMed: 32525915
DOI: 10.1371/journal.pone.0234502 -
Revista Argentina de Microbiologia 2019Reference fungal cultures (RFCs) are essential for the internal quality control of laboratories. The production of these cultures requires standardized procedures (IRAM...
Reference fungal cultures (RFCs) are essential for the internal quality control of laboratories. The production of these cultures requires standardized procedures (IRAM 14950:2016 and ISO 17034:2016 standards) carried out by a recognized and accredited laboratory. The aim of this work was to produce RFC in paper disks of autochthonous strains, characterized by two, homogeneous and stable reference methods traceable at species level. RFC were produced using 14 regional species (7 yeasts and 7 filamentous fungi) from the fungal culture collection (DMic). Paper disks were impregnated with a culture suspension, dried and packed. Homogeneity, viability, identity and purity were verified. Short- and long-term stability at different temperatures and storage times were studied. Characterization of each strain allowed to confirm its identity and to ensure its traceability at international level. Produced batches were homogeneous and stable at -20±5°C for 30 months. This method of production was adequate to produce homogeneous and stable RFC with phenotypic and genotypic characteristics correctly defined and internationally traceable. Standardized procedures were developed for the production of certified RFC that could be transferred to other microorganisms. Providing RFC that represent regional strains allows laboratories to produce more reliable results with a favorable impact on medical diagnosis, the environment or the food industry.
Topics: Biological Specimen Banks; Culture Media; Fungi; Mycology; Preservation, Biological; Quality Control; Reference Standards; Yeasts
PubMed: 30591317
DOI: 10.1016/j.ram.2018.08.001 -
PloS One 2019For molecular research, the quality and integrity of DNA obtained will affect the reliability of subsequent results. Extracting quality DNA from scale insects, including... (Comparative Study)
Comparative Study
For molecular research, the quality and integrity of DNA obtained will affect the reliability of subsequent results. Extracting quality DNA from scale insects, including mealybugs, can be difficult due to their small body size and waxy coating. In this study, we evaluate eight commonly used DNA extraction methods to determine their efficacy in PCR analysis across life stages and preservation times. We find that fresh samples, immediately upon collection or after 2 wks, resulted in the most effective DNA extraction. Methods using the DNeasy Blood & Tissue kit, NaCl, SDS-RNase A, and SDS isolated DNA of sufficient quality DNA. The SDS method gave high DNA yield, while the NaCl and SDS-RNase A methods gave lower yield. NaCl, SDS-RNase A, SDS, chloroform-isopentyl alcohol, and the salting-out methods all resulted in sufficient DNA for PCR, and performed equal to or better than that of the DNeasy Blood & Tissue kit. When time and cost per extraction were considered, the SDS method was most efficient, especially for later life stages of mealybug, regardless of preservation duration. DNA extracted from a single fresh sample of a female adult mealybug was adequate for more than 10,000 PCR reactions. For earlier stages, including the egg and 1st instar nymph samples, DNA was most effectively extracted by the Rapid method. Our results provide guidelines for the choice of effective DNA extraction method for mealybug or other small insects across different life stages and preservation status.
Topics: Animals; DNA; Female; Hemiptera; Nymph; Polymerase Chain Reaction; Preservation, Biological
PubMed: 31891602
DOI: 10.1371/journal.pone.0226818 -
Molecules (Basel, Switzerland) Jan 2022In this review, recent advances in the methods of pre-treatment of plant material for the extraction of secondary metabolites with high biological activity are... (Review)
Review
In this review, recent advances in the methods of pre-treatment of plant material for the extraction of secondary metabolites with high biological activity are presented. The correct preparation of the material for extraction is as important as the selection of the extraction method. This step should prevent the degradation of bioactive compounds as well as the development of fungi and bacteria. Currently, the methods of preparation are expected to modify the particles of the plant material in such a way that will contribute to the release of bioactive compounds loosely bonded to cell wall polymers. This review presents a wide range of methods of preparing plant material, including drying, freeze-drying, convection drying, microwave vacuum drying, enzymatic processes, and fermentation. The influence of the particular methods on the structure of plant material particles, the level of preserved bioactive compounds, and the possibility of their release during the extraction were highlighted. The plant material pre-treatment techniques used were discussed with respect to the amount of compounds released during extraction as well their application in various industries interested in products with a high content of biologically active compounds, such as the pharmaceutical, cosmetics, and food industries.
Topics: Desiccation; Food Handling; Freeze Drying; Microwaves; Plants; Preservation, Biological; Vacuum
PubMed: 35163995
DOI: 10.3390/molecules27030730 -
PloS One 2022This paper proposes a new method for low-light image enhancement with balancing image brightness and preserving image details, this method can improve the brightness and...
This paper proposes a new method for low-light image enhancement with balancing image brightness and preserving image details, this method can improve the brightness and contrast of low-light images while maintaining image details. Traditional histogram equalization methods often lead to excessive enhancement and loss of details, thereby resulting in an unclear and unnatural appearance. In this method, the image is processed bidirectionally. On the one hand, the image is processed by double histogram equalization with double automatic platform method based on improved cuckoo search (CS) algorithm, where the image histogram is segmented firstly, and the platform limit is selected according to the histogram statistics and improved CS technology. Then, the sub-histograms are clipped by two platforms and carried out the histogram equalization respectively. Finally, an image with balanced brightness and good contrast can be obtained. On the other hand, the main structure of the image is extracted based on the total variation model, and the image mask with all the texture details is made by removing the main structure of the image. Eventually, the final enhanced image is obtained by adding the mask with texture details to the image with balanced brightness and good contrast. Compared with the existing methods, the proposed algorithm significantly enhances the visual effect of the low-light images, based on human subjective evaluation and objective evaluation indices. Experimental results show that the proposed method in this paper is better than the existing methods.
Topics: Algorithms; Humans; Image Enhancement; Preservation, Biological
PubMed: 35639677
DOI: 10.1371/journal.pone.0262478 -
Fertility and Sterility Nov 2006This bulletin will review the various viral etiologies of hepatitis, their mode of transmission, and implications for infertile couples, pregnant women, and health care... (Review)
Review
This bulletin will review the various viral etiologies of hepatitis, their mode of transmission, and implications for infertile couples, pregnant women, and health care workers.
Topics: Cryopreservation; Embryo, Mammalian; Female; Hepatitis, Viral, Human; Humans; Infant, Newborn; Insemination, Artificial, Heterologous; Male; Pregnancy; Pregnancy Complications, Infectious; Preservation, Biological; Reproductive Techniques, Assisted; Semen
PubMed: 17055810
DOI: 10.1016/j.fertnstert.2006.08.081 -
Microbiology Spectrum Oct 2021Storage of biological specimens is crucial in the life and medical sciences. Storage conditions for samples can be different for a number of reasons, and it is unclear... (Comparative Study)
Comparative Study
Storage of biological specimens is crucial in the life and medical sciences. Storage conditions for samples can be different for a number of reasons, and it is unclear what effect this can have on the inferred microbiome composition in metagenomics analyses. Here, we assess the effect of common storage temperatures (deep freezer, -80°C; freezer, -20°C; refrigerator, 5°C; room temperature, 22°C) and storage times (immediate sample processing, 0 h; next day, 16 h; over weekend, 64 h; longer term, 4, 8, and 12 months) as well as repeated sample freezing and thawing (2 to 4 freeze-thaw cycles). We examined two different pig feces and sewage samples, unspiked and spiked with a mock community, in triplicate, respectively, amounting to a total of 438 samples (777 Gbp; 5.1 billion reads). Storage conditions had a significant and systematic effect on the taxonomic and functional composition of microbiomes. Distinct microbial taxa and antimicrobial resistance classes were, in some situations, similarly affected across samples, while others were not, suggesting an impact of individual inherent sample characteristics. With an increasing number of freeze-thaw cycles, an increasing abundance of , , and eukaryotic microorganisms was observed. We provide recommendations for sample storage and strongly suggest including more detailed information in the metadata together with the DNA sequencing data in public repositories to better facilitate meta-analyses and reproducibility of findings. Previous research has reported effects of DNA isolation, library preparation, and sequencing technology on metagenomics-based microbiome composition; however, the effect of biospecimen storage conditions has not been thoroughly assessed. We examined the effect of common sample storage conditions on metagenomics-based microbiome composition and found significant and, in part, systematic effects. Repeated freeze-thaw cycles could be used to improve the detection of microorganisms with more rigid cell walls, including parasites. We provide a data set that could also be used for benchmarking algorithms to identify and correct for unwanted batch effects. Overall, the findings suggest that all samples of a microbiome study should be stored in the same way. Furthermore, there is a need to mandate more detailed information about sample storage and processing be published together with DNA sequencing data at the International Nucleotide Sequence Database Collaboration (ENA/EBI, NCBI, DDBJ) or other repositories.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Drug Resistance, Bacterial; Feces; Humans; Microbiota; Preservation, Biological; Sewage; Specimen Handling; Swine; Temperature; Time Factors
PubMed: 34612701
DOI: 10.1128/Spectrum.01387-21