Halogenated monoterpenes from Namibian Plocamium rigidum: Accurate quantification and chemotaxonomic relevance

Accurate quantification of biological resistance has been impossible so far. Among the various forms of biological resistance which exist in nature, pathogen resistance to drugs is a familiar one. However, as in the case of other forms of resistance, accurately quantifying drug resistance in pathogens has been impossible up to now. Here, we introduce a mathematically-defined and uniform procedure for the absolute quantification of biological resistance deployed by any living organism in the biological realm, including and beyond drug resistance in medicine. The scheme introduced makes possible the exact measurement or computation of the extent to which resistance is deployed by any living organism regardless of kingdom and regardless of the mechanism of resistance involved. Furthermore, the Second Law of Resistance indicating that resistance has the potential to increase to infinite levels, and the Third Law of Resistance indicating that resistance comes to an end once interaction stops, the resistance unit function introduced here is fully compatible with both the Second and Third Laws of Resistance.

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Characterization and Quantification of Selenoprotein P: Challenges to Mass Spectrometry

International Journal of Molecular Sciences ◽

10.3390/ijms22126283 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6283

Author(s):

Jérémy Lamarche ◽

Luisa Ronga ◽

Joanna Szpunar ◽

Ryszard Lobinski

Keyword(s):

Mass Spectrometry ◽

State Of The Art ◽

Animal Health ◽

Primary Standard ◽

Selenoprotein P ◽

Primary Standards ◽

Analytical Approaches ◽

Careful Investigation ◽

Accurate Quantification

Selenoprotein P (SELENOP) is an emerging marker of the nutritional status of selenium and of various diseases, however, its chemical characteristics still need to be investigated and methods for its accurate quantitation improved. SELENOP is unique among selenoproteins, as it contains multiple genetically encoded SeCys residues, whereas all the other characterized selenoproteins contain just one. SELENOP occurs in the form of multiple isoforms, truncated species and post-translationally modified variants which are relatively poorly characterized. The accurate quantification of SELENOP is contingent on the availability of specific primary standards and reference methods. Before recombinant SELENOP becomes available to be used as a primary standard, careful investigation of the characteristics of the SELENOP measured by electrospray MS and strict control of the recoveries at the various steps of the analytical procedures are strongly recommended. This review critically discusses the state-of-the-art of analytical approaches to the characterization and quantification of SELENOP. While immunoassays remain the standard for the determination of human and animal health status, because of their speed and simplicity, mass spectrometry techniques offer many attractive and complementary features that are highlighted and critically evaluated.

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A Method for the Accurate Quantification of Gas Streams by Online Mass Spectrometry

Journal of the American Society for Mass Spectrometry ◽

10.1021/jasms.1c00090 ◽

2021 ◽

Author(s):

Edwing Alexander Velasco-Rozo ◽

Luz Marina Ballesteros-Rueda ◽

Víctor Gabriel Baldovino-Medrano

Keyword(s):

Mass Spectrometry ◽

Gas Streams ◽

Accurate Quantification

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Biological responses in pesticide exposed lizards (Podarcis siculus)

Ecotoxicology ◽

10.1007/s10646-021-02440-3 ◽

2021 ◽

Author(s):

Giulia Simbula ◽

Ginevra Moltedo ◽

Barbara Catalano ◽

Giacomo Martuccio ◽

Claudia Sebbio ◽

...

Keyword(s):

Oxidative Stress ◽

Central Italy ◽

Parasitic Infection ◽

Biotransformation Enzymes ◽

Biological Responses ◽

Podarcis Siculus ◽

Parasite Infections ◽

Italian Wall Lizard ◽

Detoxification Process ◽

Accurate Quantification

AbstractThe release of contaminants as herbicides, fungicides and insecticides into the environment has been listed as one of the six major contributors to the global decline of reptiles. Although reptiles may face severe risk from contaminants due to their ecology and physiology, they are currently less studied than other vertebrate groups. In the present work, we investigated if and how different types of field treatment (conventional and organic) affected the health status of Italian wall lizard (Podarcis siculus) individuals in central Italy. We chose a multi-biomarker approach that evaluated the biological responses of lizards to the treatment by means of AChE activity in the nervous system, biotransformation enzymes activities and oxidative stress in the liver, micronuclei frequency measured in the erythrocytes, and rate of intestinal parasitic infection. Our findings showed evidence of effects of treatment in conventional areas and between sexes with significant oxidative stress due to hydroxyl radicals, that caused DNA damage. No difference of intestinal parasite infections was found among treatments. Podarcis siculus seems to be a good bioindicator in ecotoxicological studies and potentially in risk assessment of pesticides, although further analyses in laboratory and in the field are needed to achieve more accurate quantification of specific pesticide effects in relation to known exposure history and to understand if other mechanisms were involved in the toxicity and detoxification process of pesticides for this species.

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Quantifying Habitual Physical Activity and Sedentariness in Older Adults—Different Outcomes of Two Simultaneously Body-Worn Motion Sensor Approaches and a Self-Estimation

Sensors ◽

10.3390/s20071877 ◽

2020 ◽

Vol 20 (7) ◽

pp. 1877

Author(s):

Rieke Trumpf ◽

Wiebren Zijlstra ◽

Peter Haussermann ◽

Tim Fleiner

Keyword(s):

Physical Activity ◽

Older Adults ◽

Community Dwelling ◽

Habitual Physical Activity ◽

Motion Sensor ◽

Motion Sensors ◽

Healthy Older Adults ◽

Lower Back ◽

Hybrid Motion ◽

Accurate Quantification

Applicable and accurate assessment methods are required for a clinically relevant quantification of habitual physical activity (PA) levels and sedentariness in older adults. The aim of this study is to compare habitual PA and sedentariness, as assessed with (1) a wrist-worn actigraph, (2) a hybrid motion sensor attached to the lower back, and (3) a self-estimation based on a questionnaire. Over the course of one week, PA of 58 community-dwelling subjectively healthy older adults was recorded. The results indicate that actigraphy overestimates the PA levels in older adults, whereas sedentariness is underestimated when compared to the hybrid motion sensor approach. Significantly longer durations (hh:mm/day) for all PA intensities were assessed with the actigraph (light: 04:19; moderate to vigorous: 05:08) when compared to the durations (hh:mm/day) that were assessed with the hybrid motion sensor (light: 01:24; moderate to vigorous: 02:21) and the self-estimated durations (hh:mm/day) (light: 02:33; moderate to vigorous: 03:04). Actigraphy-assessed durations of sedentariness (14:32 hh:mm/day) were significantly shorter when compared to the durations assessed with the hybrid motion sensor (20:15 hh:mm/day). Self-estimated duration of light intensity was significantly shorter when compared to the results of the hybrid motion sensor. The results of the present study highlight the importance of an accurate quantification of habitual PA levels and sedentariness in older adults. The use of hybrid motion sensors can offer important insights into the PA levels and PA types (e.g., sitting, lying) and it can increase the knowledge about mobility-related PA and patterns of sedentariness, while actigraphy appears to be not recommendable for this purpose.

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Accurate Quantification of Sulfonamide Metabolites in Goat Meat: A New Strategy for Minimizing Interaction between Sheep Serum Albumin and Sulfonamide Metabolites

Journal of Agricultural and Food Chemistry ◽

10.1021/acs.jafc.1c02496 ◽

2021 ◽

Author(s):

Wei Jia ◽

Min Zhang ◽

An Du ◽

Rong Zhang ◽

Mudan Xu ◽

...

Keyword(s):

Serum Albumin ◽

Goat Meat ◽

New Strategy ◽

Accurate Quantification

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Data-Independent Acquisition for the Quantification and Identification of Metabolites in Plasma

Metabolites ◽

10.3390/metabo10120514 ◽

2020 ◽

Vol 10 (12) ◽

pp. 514

Author(s):

Tom van der Laan ◽

Isabelle Boom ◽

Joshua Maliepaard ◽

Anne-Charlotte Dubbelman ◽

Amy C. Harms ◽

...

Keyword(s):

Mass Spectra ◽

Mass Range ◽

Correct Identification ◽

Hydrophilic Interaction ◽

Specific Mass ◽

Structural Isomers ◽

Data Independent Acquisition ◽

Targeted Analysis ◽

Theoretical Mass ◽

Accurate Quantification

A popular fragmentation technique for non-targeted analysis is called data-independent acquisition (DIA), because it provides fragmentation data for all analytes in a specific mass range. In this work, we demonstrated the strengths and weaknesses of DIA. Two types of chromatography (fractionation/3 min and hydrophilic interaction liquid chromatography (HILIC)/18 min) and three DIA protocols (variable sequential window acquisition of all theoretical mass spectra (SWATH), fixed SWATH and MSALL) were used to evaluate the performance of DIA. Our results show that fast chromatography and MSALL often results in product ion overlap and complex MS/MS spectra, which reduces the quantitative and qualitative power of these DIA protocols. The combination of SWATH and HILIC allowed for the correct identification of 20 metabolites using the NIST library. After SWATH window customization (i.e., variable SWATH), we were able to quantify ten structural isomers with a mean accuracy of 103% (91–113%). The robustness of the variable SWATH and HILIC method was demonstrated by the accurate quantification of these structural isomers in 10 highly diverse blood samples. Since the combination of variable SWATH and HILIC results in good quantitative and qualitative fragmentation data, it is promising for both targeted and untargeted platforms. This should decrease the number of platforms needed in metabolomics and increase the value of a single analysis.

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