scholarly journals A non-enzymatic, isothermal strand displacement and amplification assay for rapid detection of SARS-CoV-2 RNA

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Mohsen Mohammadniaei ◽  
Ming Zhang ◽  
Jon Ashley ◽  
Ulf Bech Christensen ◽  
Lennart Jan Friis-Hansen ◽  
...  
Keyword(s):  
Signal Amplification ◽  
Rapid Detection ◽  
Room Temperature ◽  
Storage Conditions ◽  
Strand Displacement ◽  
Rna Detection ◽  
Reverse Transcription Step ◽  
Amplification Assay ◽  
User Friendly ◽  
And Storage

AbstractThe current nucleic acid signal amplification methods for SARS-CoV-2 RNA detection heavily rely on the functions of biological enzymes which imposes stringent transportation and storage conditions, high cost and global supply shortages. Here, a non-enzymatic whole genome detection method based on a simple isothermal signal amplification approach is developed for rapid detection of SARS-CoV-2 RNA and potentially any types of nucleic acids regardless of their size. The assay, termed non-enzymatic isothermal strand displacement and amplification (NISDA), is able to quantify 10 RNA copies.µL−1. In 164 clinical oropharyngeal RNA samples, NISDA assay is 100 % specific, and it is 96.77% and 100% sensitive when setting up in the laboratory and hospital, respectively. The NISDA assay does not require RNA reverse-transcription step and is fast (<30 min), affordable, highly robust at room temperature (>1 month), isothermal (42 °C) and user-friendly, making it an excellent assay for broad-based testing.

scholarly journals Effects of Storage Conditions on Postharvest Qualities in Garlic Bulbs (Allium sativum L.)

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 805C-805
Author(s):  
Sun-Tay Choi ◽  
Ro-Na Bae* ◽  
Dae-Sung Chung ◽  
Seung-Koo Lee
Keyword(s):  
Weight Loss ◽  
Low Temperature ◽  
Pyruvic Acid ◽  
Room Temperature ◽  
Allium Sativum ◽  
Storage Period ◽  
Storage Conditions ◽  
Controlled Atmosphere ◽  
Atmosphere Storage ◽  
And Storage

To investigate quality changes of garlic associated with cultivars and storage conditions, northern type `Seosan' and sub-tropical type `Daeseo' garlics were stored at controlled atmosphere (O2 3%, CO2 5%, -1 ± 1°C) condition, low temperature (-1 ± 1°C), and room temperature (20 ± 5°C). The rate of sprouting, weight loss, enzymatic pyruvic acid content, and degree of greening in crushed garlic were determined during storage. The rate of sprouting was higher in `Daeseo' than in `Seosan' garlic in all storage conditions. Sprouting was effectively suppressed in low temperature and controlled atmosphere storage. Weight loss in `Daeseo' garlic was higher than in `Seosan' garlic. Enzymatic pyruvic acid (EP) contents increased for 3 months storage period, and then decreased gradually as the storage period was prolonged at room or low temperatures. However, EP content decreased dramatically during storage under CA condition in both cultivars. When garlic bulbs were crushed, greening appeared in the garlic stored at low temperature for more than one month. However, greening did not occur in the crushed garlic bulbs stored in CA condition.

Effects of Flavorings, Storage Conditions, and Storage Time on Survival of Staphylococcus aureus in Sürk Cheese

2005 ◽  
Vol 68 (7) ◽  
pp. 1487-1491 ◽  
Author(s):  
TUĞRUL M. MASATCIOĞLU ◽  
YAHYA K. AVŞAR
Keyword(s):  
Staphylococcus Aureus ◽  
Room Temperature ◽  
Storage Time ◽  
Storage Conditions ◽  
Black Pepper ◽  
Ash Content ◽  
Mold Growth ◽  
Storage Duration ◽  
And Storage ◽  
Over Time

The objectives of this study were to determine the cumulative effects of flavorings (chili pepper, thyme, mint, cumin, nutmeg, allspice, clove, cinnamon, black pepper, salt, and hot red pepper paste), storage conditions, and storage time on the survival of Staphylococcus aureus in Sürk cheese and to monitor the associated chemical changes. Sürk cheese, a traditional Turkish cheese, was produced by heating diluted nonfat yogurt and adding flavorings to the resultant acid-heat curd. The cheese was later inoculated with S. aureus, shaped conically, and stored aerobically for mold growth and anaerobically in olive oil for 30 days at room temperature. The moisture content of aerobically stored cheese decreased over time and led to increases in total solids, salt, salt-in-moisture, and ash content during ripening (P &lt; 0.05). The presence or absence of the flavorings had no significant effect, whereas storage conditions and storage duration decreased the survival of S. aureus (P &lt; 0.05).

scholarly journals Directions of Colour Changes of Nectar Honeys Depending on Honey Type and Storage Conditions

2015 ◽  
Vol 59 (2) ◽  
pp. 51-61 ◽  
Author(s):  
Allna Piotraszewska-Pająk ◽  
Anna Gliszczyńska-Świgło
Keyword(s):  
Room Temperature ◽  
Quality Criteria ◽  
Storage Conditions ◽  
Room Temperature Storage ◽  
Long Term Storage ◽  
Colour Parameters ◽  
Colour Changes ◽  
Important Quality ◽  
And Storage ◽  
Temperature Storage

AbstractThe colour of honey is one of the most important quality criteria for consumers. The colour depends mainly on the content of plant pigments but the honey consistency, shape, and size of the crystals may also influence the honey colour parameters. It is related to the crystallisation and decrystallisation processes of honey during storage. In the present study, directions of colour changes of honey during storage were evaluated using a tristimulus colorimeter and the CIE 1976 L*a*b* and CIE L*C*hosystems. The effect of time (3 and 9 months) and storage conditions (cold storage, room temperature storage with access to light, and room temperature storage without access to light) on the colour of nectar honeys was investigated. The results obtained showed that both the type of honey and the storage conditions influenced the honey colour parameters. Significant differences in direction and intensity of the colour changes of honey during storage were observed. These differences make it difficult to indicate which storage conditions are optimal to preserve the colour of the honey. It was found that acacia and heather honeys were the most susceptible to colour changes during long-term storage in all of the study’s applied conditions, whereas rape and buckwheat honeys were the most stable in colour parameters.

scholarly journals Effect of Storage Conditions on Quality and Shelf Life of Pumpkin Cookies

2020 ◽  
pp. 70-79
Keyword(s):  
Chemical Analysis ◽  
Environmental Conditions ◽  
Room Temperature ◽  
Storage Stability ◽  
Storage Conditions ◽  
Packaging Material ◽  
Spread Ratio ◽  
Physico Chemical ◽  
And Storage ◽  
Quality And Shelf Life

The chemical, physical evaluation and storage stability of cookies was carried out. studies on quality was based on physico-chemical analysis that is weight, diameter, thickness ,spread ratio, moisture, fat, protein, ash, crude fiber, carbohydrate content as well as sensory characteristics which was determined for fresh and stored sample. The characteristics of cookies were influenced by packaging material, environmental conditions and constituents present in flour. Cookies was packed in LDPE bags and stored at room temperature. This study was conducted at the interval of 15 days up to 45days.

Testing achene germinationof Potamogeton praelongus Wulfen

2013 ◽  
Vol 8 (1) ◽  
pp. 78-86 ◽  
Author(s):  
Romana Prausová ◽  
Jana Janová ◽  
Lenka Šafářová
Keyword(s):  
Room Temperature ◽  
Germination Rate ◽  
Storage Conditions ◽  
Natural Process ◽  
Anaerobic Conditions ◽  
Mechanical Disruption ◽  
Breaking Dormancy ◽  
Petri Dishes ◽  
And Storage ◽  
Uva Radiation

AbstractThe goal of this work was to determine the best method of breaking the achene dormancy in Potamogeton praelongus Wulfen. The ways of breaking achene dormancy studied in this experiment included methods of achene storage, stratification, UVA radiation, anaerobic conditions, mechanical disruption of achenes?outer layers and their chemical disruption by NaClO. Nine different treatments of achenes were combined with two methods of achene storage. Particular achene treatments and storage conditions were proven to have a significant impact on breaking dormancy. Although the highest germination rate (83.3%) was achieved when the dormancy was broken chemically by long effect of 100% concentrations of Savo detergent (containing 5% NaClO), the growth of the sprouts was subsequently inhibited due to toxic effects of Savo. Thus the most successful treatment was based on changing temperature, e.g. 2.5 months of cold storage followed by 14 days at room temperature (germination rate 32.7%). This treatment was also most similar to the natural process. Germinated achenes were also found in Petri dishes exposed to UVA radiation, anaerobic conditions and chemical disruption of the outer layers. Results of these treatments were influenced by the storage method.

scholarly journals Systematic Analysis of Impact of Sampling Regions and Storage Methods on Fecal Gut Microbiome and Metabolome Profiles

mSphere ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Yali Liang ◽  
Tianyu Dong ◽  
Minjian Chen ◽  
Lianping He ◽  
Tingzhang Wang ◽  
...  
Keyword(s):  
Gut Microbiome ◽  
Room Temperature ◽  
Storage Conditions ◽  
Minimal Effect ◽  
Sample Storage ◽  
Short Term ◽  
Room Temperature Storage ◽  
Stool Samples ◽  
And Storage ◽  
Temperature Storage

ABSTRACT The contribution of human gastrointestinal (GI) microbiota and metabolites to host health has recently become much clearer. However, many confounding factors can influence the accuracy of gut microbiome and metabolome studies, resulting in inconsistencies in published results. In this study, we systematically investigated the effects of fecal sampling regions and storage and retrieval conditions on gut microbiome and metabolite profiles from three healthy children. Our analysis indicated that compared to homogenized and snap-frozen samples (standard control [SC]), different sampling regions did not affect microbial community alpha diversity, while a total of 22 of 176 identified metabolites varied significantly across different sampling regions. In contrast, storage conditions significantly influenced the microbiome and metabolome. Short-term room temperature storage had a minimal effect on the microbiome and metabolome profiles. Sample storage in RNALater showed a significant level of variation in both microbiome and metabolome profiles, independent of the storage or retrieval conditions. The effect of RNALater on the metabolome was stronger than the effect on the microbiome, and individual variability between study participants outweighed the effect of RNALater on the microbiome. We conclude that homogenizing stool samples was critical for metabolomic analysis but not necessary for microbiome analysis. Short-term room temperature storage had a minimal effect on the microbiome and metabolome profiles and is recommended for short-term fecal sample storage. In addition, our study indicates that the use of RNALater as a storage medium of stool samples for microbial and metabolomic analyses is not recommended. IMPORTANCE The gastrointestinal microbiome and metabolome can provide a new angle to understand the development of health and disease. Stool samples are most frequently used for large-scale cohort studies. Standardized procedures for stool sample handling and storage can be a determining factor for performing microbiome or metabolome studies. In this study, we focused on the effects of stool sampling regions and stool sample storage conditions on variations in the gut microbiome composition and metabolome profile.

scholarly journals Induced encystment improves resistance to preservation and storage of Acanthamoeba castellanii

Parasitology ◽  
2008 ◽  
Vol 135 (12) ◽  
pp. 1401-1405 ◽  
Author(s):  
S. J. CAMPBELL ◽  
P. R. INGRAM ◽  
C. W. ROBERTS ◽  
F. L. HENRIQUEZ
Keyword(s):  
Adverse Effects ◽  
Dimethyl Sulfoxide ◽  
Room Temperature ◽  
Acanthamoeba Castellanii ◽  
Storage Conditions ◽  
Multiplicative Form ◽  
Efficient Recovery ◽  
And Storage

SUMMARYSeveral conditions that allow the preservation, storage and rapid, efficient recovery of viable Acanthamoeba castellanii organisms were investigated. The viability of trophozoites (as determined by time to confluence) significantly declined over a period of 12 months when stored at −70°C using dimethyl sulfoxide (DMSO; 5 or 10%) as cryopreservant. As A. castellanii are naturally capable of encystment, studies were undertaken to determine whether induced encystment might improve the viability of organisms under a number of storage conditions. A. castellanii cysts stored in the presence of Mg2+ at 4°C remained viable over the study period, although time to confluence was increased from approximately 8 days to approximately 24 days over the 12-month period. Storage of cysts at −70°C with DMSO (5 or 10%) or 40% glycerol, but not 80% glycerol as cryopreservants increased their viability over the 12-month study period compared with those stored at room temperature. Continued presence of Mg2+ in medium during storage had no adverse effects and generally improved recovery of viable organisms. The present study demonstrates that A. castellanii can be stored as a non-multiplicative form inexpensively, without a need for cryopreservation, for at least 12 months, but viability is increased by storage at −70°C.

scholarly journals Furosemide in water matrix: HPLC-UV method development and degradation studies

2020 ◽  
Vol 15 (1) ◽  
pp. 1
Author(s):  
Ana Isabel Machado ◽  
Rita Fragoso ◽  
Ana Vitória Martins Neves Barrocas Dordio ◽  
Elizabeth Duarte
Keyword(s):  
High Performance ◽  
Room Temperature ◽  
Method Development ◽  
Storage Temperature ◽  
Light Exposure ◽  
High Performance Liquid Chromatographic ◽  
Storage Conditions ◽  
Chromatographic Technique ◽  
Recovery Capacity ◽  
And Storage

This study developed a method for furosemide quantification through high performance liquid chromatographic technique. Special attention was given to solute loss and storage stability due to furosemide’s low solubility and photosensitivity, respectively. The performance of Nylon and PVDF filters was tested in a 2 mg.L-1 furosemide solution. PVDF filters showed better recovery capacity and therefore are more suitable for furosemide filtration.  Over eight days, three different storage conditions were studied to access furosemide degradation susceptibility: (i) exposure to light at room temperature, (ii) storage at room temperature without exposure to light, and (iii) storage at 4ºC without exposure to light. The study demonstrated that after 48 h under natural light exposure furosemide was completely degraded. Furosemide solution stored in the dark was stable. Storage temperature did not seem to affect furosemide concentration. The study shows that the selection of more suitable filter and storage conditions for furosemide determination is crucial to avoid underestimation errors.

scholarly journals Effects of Various Handling and Storage Conditions on Stability of Treponema pallidum DNA in Cerebrospinal Fluid

1998 ◽  
Vol 36 (7) ◽  
pp. 2117-2119 ◽  
Author(s):  
A. V. Villanueva ◽  
R. P. Podzorski ◽  
M. P. Reyes
Keyword(s):  
Central Nervous System ◽  
Cerebrospinal Fluid ◽  
Nervous System ◽  
Room Temperature ◽  
Treponema Pallidum ◽  
Storage Conditions ◽  
Freeze Thaw ◽  
Target Dna ◽  
The Central Nervous System ◽  
And Storage

Treponema pallidum DNA from even small numbers of organisms was detectable in cerebrospinal fluid (CSF) stored at room temperature or at 4°C for several hours and in CSF subjected to three freeze-thaw cycles. These results suggest that negative PCR results forT. pallidum from patients diagnosed with T. pallidum invasion of the central nervous system are probably not due to the loss of target DNA prior to testing.

Sign in / Sign up

Export Citation Format

Share Document