scholarly journals Harmless or Threatening? Interpreting the Results of Molecular Diagnosis in the Context of Virus-Host Relationships

2021 ◽  
Vol 12 ◽  
Author(s):  
Fábio A. Abade dos Santos ◽  
Sara J. Portela ◽  
Teresa Nogueira ◽  
Carina L. Carvalho ◽  
Rita de Sousa ◽  
...  
Keyword(s):  
Nucleic Acids ◽  
Molecular Diagnosis ◽  
Biological Samples ◽  
Clinical Evidence ◽  
Molecular Methods ◽  
Nucleotide Sequencing ◽  
Host Relationships ◽  
The Difference

Molecular methods, established in the 1980s, expanded and delivered tools for the detection of vestigial quantities of nucleic acids in biological samples. Nucleotide sequencing of these molecules reveals the identity of the organism it belongs to. However, the implications of such detection are often misinterpreted as pathogenic, even in the absence of corroborating clinical evidence. This is particularly significant in the field of virology where the concepts of commensalism, and other benign or neutral relationships, are still very new. In this manuscript, we review some fundamental microbiological concepts including commensalism, mutualism, pathogenicity, and infection, giving special emphasis to their application in virology, in order to clarify the difference between detection and infection. We also propose a system for the correct attribution of terminology in this context.

Attempts of Transmission of the Newt Melanoma by Nucleic Acids Preparations.

1974 ◽  
Vol 60 (2) ◽  
pp. 123-141
Author(s):  
Teresa Zavanella ◽  
Edgarda Camerini
Keyword(s):  
Biological Activity ◽  
Nucleic Acids ◽  
Geographical Origin ◽  
Triturus Cristatus ◽  
Normal Organ ◽  
Normal Tissues ◽  
Dnase Treatment ◽  
Cent Level ◽  
The Difference ◽  
Tumorigenic Activity

In the present study attempts were made to obtain DNA extracts with tumorigenic activity from the melanoma of the newt (Triturus cristatus Laur.). The DNA, prepared by two different methods from melanomas that had been transferred by cells for several generations, was injected subcutaneously in adult animals. Control animals were not treated or received DNA isolated from normal homologous organs. In all 320 animals were used, 238 of which were given DNA. The DNA preparations obtained according to the procedure of Colter et al. failed to induce tumors in any of the 111 inoculated animals, while the treatment with DNA extracted according to Kirby's method (127 cases) from tumors as well from normal tissues resulted in the development of melanomas with an incidence significantly higher than that observed in the group of untreated animals; however, the activity of the extracts was not modified by DNase treatment. The influence of factors such as neoplasia spread in the donors, duration of observation, geographical origin of animals and season of treatment was considered. Altogether 934 animals were studied, including those of other experimental series reported elsewhere: 670 were given nucleic acids extracted from tumors or normal organs, 204 received tumor or normal organ transplants, 60 were untreated. Of interest is the fact that the overall incidence of melanoma was much high in animals coming from areas of high industrialization, i.e. in the newts from the environs of Pavia (54.1 %), than in those from Naples (11 %): the difference between the two groups was highly significant and independent of the treatment. Due to the high tumor incidence in the newts from Pavia, no correlation could be demonstrated between biological activity of nucleic acid extracts and the above mentioned factors in the 670 animals treated. However, in the case of the newts from the Naples area a higher frequency of tumors was observed after treatment with nucleic acids extracted from melanoma, than after treatment with nucleic acids from normal organs: the result is statistically significant only at the 5 per cent level with the χ2 test.

Dual-Domain Microchip-Based Process for Volume Reduction Solid Phase Extraction of Nucleic Acids from Dilute, Large Volume Biological Samples

2010 ◽  
Vol 82 (13) ◽  
pp. 5669-5678 ◽  
Author(s):  
Carmen R. Reedy ◽  
Kristin A. Hagan ◽  
Briony C. Strachan ◽  
Joshua J. Higginson ◽  
Joan M. Bienvenue ◽  
...  
Keyword(s):  
Nucleic Acids ◽  
Solid Phase Extraction ◽  
Large Volume ◽  
Biological Samples ◽  
Solid Phase ◽  
Volume Reduction ◽  
Phase Extraction ◽  
Dual Domain

Determination of Mercury in Biological Materials

1970 ◽  
Vol 53 (6) ◽  
pp. 1172-1175 ◽  
Author(s):  
M T Jeffus ◽  
J S Elkins ◽  
C T Kenner
Keyword(s):  
Sulfuric Acid ◽  
Standard Deviation ◽  
Nitric Acid ◽  
Biological Samples ◽  
Room Temperature ◽  
Gold Foil ◽  
Average Recovery ◽  
Average Value ◽  
The Difference

Abstract Mercury in biological samples is determined by digestion in nitric acid, sulfuric acid, and permanganate, followed by reduction and aeration for measurement by atomic absorption at room temperature. The average recovery is 95.8% with a standard deviation of 13.3%. The standard deviation, calculated from the difference between duplicates of 23 samples, is 0.063 μg mercury, which represents 9.4% of the average value of the samples. The method is simple and requires approximately 4 hr for completion. Mercury can be confirmed by adsorption on gold foil after maximum absorbance has been obtained during aeration.

scholarly journals Selecting short length nucleic acids localized in exosomes improves plasma EGFR mutation detection in NSCLC patients

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Yoonjung Kim ◽  
Saeam Shin ◽  
Boyeon Kim ◽  
Kyung-A Lee
Keyword(s):  
Nucleic Acids ◽  
Mutant Allele ◽  
Mutation Testing ◽  
Short Length ◽  
Lung Cancer Patients ◽  
Dna And Rna ◽  
Detection Assay ◽  
Positive Rate ◽  
The Difference ◽  
Nsclc Patients

Abstract Background Exosomal nucleic acid (exoNA) is a feasible target to improve the sensitivity of EGFR mutation testing in non-small cell lung cancer patients with limited cell-free DNA (cfDNA) mutant copies. However, the type and size of target exoNA related to the sensitivity of EGFR mutation testing has not been explored extensively. Methods The type and size of target exoNA related to the sensitivity of EGFR mutation testing was evaluated using ddPCR. A total of 47 plasma samples was tested using short-length exoTNA (exosomal DNA and RNA) and cfDNA. Results The sensitivity of short-length exoTNA (76.5%) was higher than that of cfDNA (64.7%) for detecting EGFR mutations in NSCLC patients. In EGFR-mutant NSCLC patients with intrathoracic disease (M0/M1a) or cases with low-copy T790M, the positive rate was 63.6% (N = 7/11) and 45.5% (N = 5/11) for short-length exoTNA and cfDNA, respectively. On average, the number absolute mutant copies of short-length exoTNA were 1.5 times higher than that of cfDNA. The mutant allele copies (Ex19del and T790M) in short-length exoTNA were relatively well preserved at 4 weeks after storage. The difference (%) in absolute mutant allele copies (Ex19del) between 0 days and 4 weeks after storage was − 61.0% for cfDNA. Conclusion Target nucleic acids and their size distribution may be critical considerations for selecting an extraction method and a detection assay. A short-length exoTNA (200 bp) contained more detectable tumor-derived nucleic acids than exoDNA (~ 200 bp length or a full-length) or cfDNA. Therefore, a short-length exoTNA as a sensitive biomarker might be useful to detect EGFR mutants for NSCLC patients with low copy number of the mutation target.

Allosteric Molecular Beacons for Sensitive Detection of Nucleic Acids, Proteins, and Small Molecules in Complex Biological Samples

2011 ◽  
Vol 17 (33) ◽  
pp. 9042-9046 ◽  
Author(s):  
Yanling Song ◽  
Liang Cui ◽  
Jie Wu ◽  
Weiting Zhang ◽  
Wei Yun Zhang ◽  
...  
Keyword(s):  
Nucleic Acids ◽  
Small Molecules ◽  
Biological Samples ◽  
Molecular Beacons ◽  
Sensitive Detection

Microfluidic module for automated isolation and purification of nucleic acids from biological samples

2010 ◽  
Vol 435 (1) ◽  
pp. 291-294 ◽  
Author(s):  
D. A. Khodakov ◽  
D. D. Mamaev ◽  
E. I. Dementieva ◽  
I. V. Filatov ◽  
D. A. Yurasov ◽  
...  
Keyword(s):  
Nucleic Acids ◽  
Biological Samples ◽  
Isolation And Purification

scholarly journals THE BASE COMPOSITION OF NUCLEIC ACIDS IN CHROMOSOMES, PUFFS, NUCLEOLI, AND CYTOPLASM OF CHIRONOMUS SALIVARY GLAND CELLS

1962 ◽  
Vol 14 (3) ◽  
pp. 371-379 ◽  
Author(s):  
Jan-Erik Edström ◽  
Wolfgang Beermann
Keyword(s):  
Salivary Gland ◽  
Nucleic Acids ◽  
Base Composition ◽  
Chromosomal Dna ◽  
Gland Cells ◽  
Salivary Gland Cells ◽  
Balbiani Rings ◽  
The Difference ◽  
Chromosome I ◽  
Chromosome Segments

The base composition of RNA from individually isolated giant chromosomes, puffed chromosome segments, nucleoli, and samples of cytoplasm from Chironomus salivary gland cells was determined by microelectrophoresis. Data on the adenine: guanine quotient of the chromosomal DNA were also obtained. The results show that: 1) Chromosomal, nucleolar, and cytoplasmic RNA's differ significantly from each other in base composition. 2) Nucleolar and cytoplasmic RNA's, in spite of the difference, show great similarities with regard to the base composition and are both rich in adenine and uracil. 3) The RNA extracted from chromosome I differs significantly from the RNA's extracted from different segments of chromosome IV, and the latter differ significantly from each other. 4) The values for the RNA: DNA quotients of chromosome segments parallel the development of synthetically active genes, so-called Balbiani rings. 5) The chromosomal RNA does not show a base symmetry in any of the investigated cases, nor is the content of guanine + cytosine the same as that for DNA. The first of these two facts excludes the possibility that the chromosomal RNA is a complete copy of both strands of the chromosomal DNA. In spite of the difference in guanine + cytosine content between the two nucleic acids the RNA may still partly or completely be a single strand copy depending upon how representative the DNA values are for the synthetically active DNA.

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