Control of Enzymatic Activities by Magnetite Nanoparticles

ABSTRACTEnzymes are proteins that catalyze chemical reactions, participating in almost all processes in the cell to achieve significant reaction rates and serving a wide variety of functions inside living organisms. Here, we intended to control enzymatic activities by applying external radio frequency magnetic field (RFMF) through nanosized antenna. Ribonuclease A (RNase A), which is a relative small protein that cleave single-stranded RNA, was conjugated to magnetite nanoparticles (NP) by non-covalent interaction. The diameters of Fe3O4 nanoparticles are less than 10nm. External RFMF was applied, and the enzymatic activities of RNase A were tuned at different levels by varying the frequencies and incubation times. Comparison results by using water bath were also presented.

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The Diverse Calpain Family in Trypanosomatidae: Functional Proteins Devoid of Proteolytic Activity?

Cells ◽

10.3390/cells10020299 ◽

2021 ◽

Vol 10 (2) ◽

pp. 299

Author(s):

Vítor Ennes-Vidal ◽

Marta Helena Branquinha ◽

André Luis Souza dos Santos ◽

Claudia Masini d’Avila-Levy

Keyword(s):

Proteolytic Activity ◽

Current Knowledge ◽

Current Therapy ◽

Calcium Dependent ◽

Administration Routes ◽

Life Threatening ◽

Living Organisms ◽

Almost All ◽

Open Question ◽

Calpain Inhibitors

Calpains are calcium-dependent cysteine peptidases that were originally described in mammals and, thereafter, their homologues were identified in almost all known living organisms. The deregulated activity of these peptidases is associated with several pathologies and, consequently, huge efforts have been made to identify selective inhibitors. Trypanosomatids, responsible for life-threatening human diseases, possess a large and diverse family of calpain sequences in their genomes. Considering that the current therapy to treat trypanosomatid diseases is limited to a handful of drugs that suffer from unacceptable toxicity, tough administration routes, like parenteral, and increasing treatment failures, a repurposed approach with calpain inhibitors could be a shortcut to successful chemotherapy. However, there is a general lack of knowledge about calpain functions in these parasites and, currently, the proteolytic activity of these proteins is still an open question. Here, we highlight the current research and perspectives on trypanosomatid calpains, overview calpain description in these organisms, and explore the potential of targeting the calpain system as a therapeutic strategy. This review gathers the current knowledge about this fascinating family of peptidases as well as insights into the puzzle: are we unable to measure calpain activity in trypanosomatids, or are the functions of these proteins devoid of proteolytic activity in these parasites?

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Circadian Deregulation as Possible New Player in Pollution-Induced Tissue Damage

Atmosphere ◽

10.3390/atmos12010116 ◽

2021 ◽

Vol 12 (1) ◽

pp. 116

Author(s):

Mascia Benedusi ◽

Elena Frigato ◽

Cristiano Bertolucci ◽

Giuseppe Valacchi

Keyword(s):

Cardiovascular Diseases ◽

Air Pollutants ◽

Environmental Stressors ◽

Common Mechanism ◽

Particulate Matters ◽

Circadian Misalignment ◽

Pathological Conditions ◽

Peripheral Clocks ◽

Living Organisms ◽

Almost All

Circadian rhythms are 24-h oscillations driven by a hypothalamic master oscillator that entrains peripheral clocks in almost all cells, tissues and organs. Circadian misalignment, triggered by industrialization and modern lifestyles, has been linked to several pathological conditions, with possible impairment of the quality or even the very existence of life. Living organisms are continuously exposed to air pollutants, and among them, ozone or particulate matters (PMs) are considered to be among the most toxic to human health. In particular, exposure to environmental stressors may result not only in pulmonary and cardiovascular diseases, but, as it has been demonstrated in the last two decades, the skin can also be affected by pollution. In this context, we hypothesize that chronodistruption can exacerbate cell vulnerability to exogenous damaging agents, and we suggest a possible common mechanism of action in deregulation of the homeostasis of the pulmonary, cardiovascular and cutaneous tissues and in its involvement in the development of pathological conditions.

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Cultural Mobility, Networks, and Theatre

Nordic Theatre Studies ◽

10.7146/nts.v32i2.124345 ◽

2021 ◽

Vol 32 (2) ◽

pp. 6-25

Author(s):

Zoltán Imre

Keyword(s):

Actual Performance ◽

Nineteenth And Twentieth Centuries ◽

Almost All ◽

Cultural Mobility ◽

Different Levels

The Budapest premiere of Henrik Ibsen’s Kísértetek (Gengangere) was on 17 October 1908 by the Thália Társaság, a Hungarian independent theatre. Though banned earlier, by 1908, Ibsen’s text had already been played all over Europe. Between 1880 and 1908, the search of IbsenStage indicates 402 records, but probably the actual performance number was higher. The popularity of the text can be seen in the fact that all the independent theatres staged it, and most of the famous and less famous travelling companies and travelling stars also kept it in their repertoires. Though, usually, the high-artistic independent and the commercial international and regional travelling companies are treated separately, here, I argue for their close real and/or virtual interconnections, creating such a theatrical and cultural network, in which the local, the regional, the national, and the transnational interacted with and were influenced by each other. At the turn of the nineteenth and twentieth centuries, such interaction among different forces and agents on different levels was one of the special features of cultural mobility (Greenblatt) which characterized intercultural theatre culture, existing in Europe and America, and extending its influence almost all over the globe.

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Factors Causing Unreliable Accounting of Electricity Consumption on the Electrified Transport “Two Wires-Rail” Longitudinal Power Supply Lines

Elektrichestvo ◽

10.24160/0013-5380-2021-9-67-72 ◽

2021 ◽

pp. 67-72

Author(s):

Elena Yu. SEMENOVA ◽

Keyword(s):

Power Supply ◽

Electromagnetic Compatibility ◽

Power Supply System ◽

Electricity Consumption ◽

Contact System ◽

Centralized Control ◽

Power Capacity ◽

Traction Substation ◽

Almost All ◽

Different Levels

As is known, the “two wires–rail” power supply system (TWR line) does not meet the modern electromagnetic compatibility requirements, which is a factor causing increased damageability of alarming, centralized control and interlocking devices, as well as other non-traction electric power consumers. In addition, there often occur unexplained differences (unbalance) in the accounting of electricity received by end users and consumed by the TWR line at a traction substation. The accomplished studies have shown that in almost all sections of the network, the actual electricity consumption is significantly lower than that recorded by the TWR line metering devices. The discrepancy in the readings could be explained by unauthorized taps of electricity. However, such a statement will be superficial. The article considers the real factors causing the unbalance in accounting the electricity consumed on the TWR line, which are explained by the magnetic influence of the contact system. An equivalent circuit of the contact system magnetic influence on the TWR line is presented for any configuration of the section with different placements of self-contained transformer substations at different levels of their power capacity. The magnetic influence of the contact system on the TWR line is illustrated by a phasor diagram.

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Predictions of diffusion rates of organic molecules in secondary organic aerosols using the Stokes-Einstein and fractional Stokes-Einstein relations

10.5194/acp-2019-191 ◽

2019 ◽

Cited By ~ 1

Author(s):

Erin Evoy ◽

Adrian M. Maclean ◽

Grazia Rovelli ◽

Ying Li ◽

Alexandra P. Tsimpidi ◽

...

Keyword(s):

Citric Acid ◽

Organic Molecules ◽

Transport Model ◽

Reaction Rates ◽

Einstein Relation ◽

Acid Mixture ◽

Chemical Transport Model ◽

Order Of Magnitude ◽

Diffusion Rates ◽

Almost All

Abstract. Information on the rate of diffusion of organic molecules within secondary organic aerosol (SOA) is needed to accurately predict the effects of SOA on climate and air quality. Often, researchers have predicted diffusion rates of organic molecules within SOA using measurements of viscosity and the Stokes-Einstein relation (D ∝ 1/η where D is the diffusion coefficient and η is viscosity). However, the accuracy of this relation for predicting diffusion in SOA remains uncertain. We measured diffusion coefficients over eight orders in magnitude in proxies of SOA including citric acid, sorbitol, and a sucrose-citric acid mixture. These results were combined with literature data to evaluate the Stokes-Einstein relation for predicting diffusion of organic molecules in SOA. Although almost all the data agrees with the Stokes-Einstein relation within a factor of ten, a fractional Stokes-Einstein relation (D ∝ C/ηt) with t = 0.93 and C = 1.66 is a better model for predicting diffusion of organic molecules in the SOA proxies studied. In addition, based on the output from a chemical transport model, the Stokes-Einstein relation can over predict mixing times of organic molecules within SOA by as much as one order of magnitude at an altitude ~ 3 km, compared to the fractional Stokes-Einstein relation with t = 0.93 and C = 1.66. These differences can be important for predicting growth, evaporation, and reaction rates of SOA in the middle and upper part of the troposphere. These results also have implications for other areas where diffusion of organic molecules within organic-water matrices is important.

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BCSExplorer: a customized biosynthetic chemical space explorer with multifunctional objective function analysis

Bioinformatics ◽

10.1093/bioinformatics/btz755 ◽

2019 ◽

Cited By ~ 1

Author(s):

Yu Tian ◽

Ling Wu ◽

Le Yuan ◽

Shaozhen Ding ◽

Fu Chen ◽

...

Keyword(s):

Chemical Space ◽

Function Analysis ◽

Supplementary Information ◽

Bulk Chemicals ◽

Toxicity Analysis ◽

Novel Method ◽

Living Organisms ◽

Almost All ◽

New Generation ◽

Rule Library

Abstract Summary The biosynthetic ability of living organisms has important applications in producing bulk chemicals, biofuels and natural products. Based on the most comprehensive biosynthesis knowledgebase, a computational system, BCSExplorer, is proposed to discover the unexplored chemical space using nature’s biosynthetic potential. BCSExplorer first integrates the most comprehensive biosynthetic reaction database with 280 000 biochemical reactions and 60 000 chemicals biosynthesized globally over the past 130 years. Second, in this study, a biosynthesis tree is computed for a starting chemical molecule based on a comprehensive biotransformation rule library covering almost all biosynthetic possibilities, in which redundant rules are removed using a new algorithm. Moreover, biosynthesis feasibility, drug-likeness and toxicity analysis of a new generation of compounds will be pursued in further studies to meet various needs. BCSExplorer represents a novel method to explore biosynthetically available chemical space. Availability and implementation BCSExplorer is available at: http://www.rxnfinder.org/bcsexplorer/. Supplementary information Supplementary data are available at Bioinformatics online.

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Engineering microbial chemical factories using metabolic models

BMC Chemical Engineering ◽

10.1186/s42480-019-0021-9 ◽

2019 ◽

Vol 1 (1) ◽

Cited By ~ 1

Author(s):

Debolina Sarkar ◽

Costas D. Maranas

Keyword(s):

Metabolic Engineering ◽

Metabolic Networks ◽

Reaction Rates ◽

Control Engineering ◽

Current Perspective ◽

Simple Molecules ◽

Living Organisms ◽

Metabolic Network Modeling ◽

And Control ◽

Analytical Approaches

Abstract Living organisms in analogy with chemical factories use simple molecules such as sugars to produce a variety of compounds which are necessary for sustaining life and some of which are also commercially valuable. The metabolisms of simple (such as bacteria) and higher organisms (such as plants) alike can be exploited to convert low value inputs into high value outputs. Unlike conventional chemical factories, microbial production chassis are not necessarily tuned for a single product overproduction. Despite the same end goal, metabolic and industrial engineers rely on different techniques for achieving productivity goals. Metabolic engineers cannot affect reaction rates by manipulating pressure and temperature, instead they have at their disposal a range of enzymes and transcriptional and translational processes to optimize accordingly. In this review, we first highlight how various analytical approaches used in metabolic engineering and synthetic biology are related to concepts developed in systems and control engineering. Specifically, how algorithmic concepts derived in operations research can help explain the structure and organization of metabolic networks. Finally, we consider the future directions and challenges faced by the field of metabolic network modeling and the possible contributions of concepts drawn from the classical fields of chemical and control engineering. The aim of the review is to offer a current perspective of metabolic engineering and all that it entails without requiring specialized knowledge of bioinformatics or systems biology.

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Non-Parametrical Canonical Analysis of Quality-Related Characteristics of Eggs of Different Varieties of Native Hens Compared to Laying Lineage

Animals ◽

10.3390/ani9040153 ◽

2019 ◽

Vol 9 (4) ◽

pp. 153 ◽

Cited By ~ 4

Author(s):

Antonio González Ariza ◽

Francisco Navas González ◽

Ander Arando Arbulu ◽

José León Jurado ◽

Cecilio Barba Capote ◽

...

Keyword(s):

Egg Quality ◽

Age Groups ◽

Individual Identification ◽

Internal Quality ◽

Control Group ◽

External Quality ◽

Shell Weight ◽

Almost All ◽

Different Levels

The aim of the present study is to characterize the productive capability of Utrerana and to compare the relationships among parameters determining the internal and external quality of the egg, through canonical correlation analysis. A flock of 68 Utrerana hens and a control group of Leghorn hens (n = 17) were housed individually to allow individual identification of eggs and for the assessment of egg quality characteristics. Almost all variables showed differences when both breeds were compared, except for white height, yolk diameter, yolkL* and yolk pH (p > 0.05). Only minor diameter, white height, yolkL*, yolka*, and shell weight reported significant differences between laying age groups. White height, yolk color, and almost all yolk color coordinates were significantly different (p < 0.05) for period and month. Egg and white weight reached highest significantly different levels for the fourth and fifth time that the hens laid an egg. External quality-related traits are better predictors of internal quality-related traits than vice versa, enabling the implementation of an effective noninvasive method for internal quality determination and egg classification aimed at suiting the needs of consumers.

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Involvement of Various Enzymes in the Physiology and Pathogenesis of Streptococcus suis

Veterinary Sciences ◽

10.3390/vetsci7040143 ◽

2020 ◽

Vol 7 (4) ◽

pp. 143

Author(s):

Chengkun Zheng ◽

Man Wei ◽

Mengdie Jia ◽

ManMan Cao

Keyword(s):

Streptococcus Suis ◽

Infection Process ◽

Swine Industry ◽

Serine Threonine Kinase ◽

Future Directions ◽

Threonine Kinase ◽

Severe Infections ◽

Living Organisms ◽

Almost All

Streptococcus suis causes severe infections in both swine and humans, making it a serious threat to the swine industry and public health. Insight into the physiology and pathogenesis of S. suis undoubtedly contributes to the control of its infection. During the infection process, a wide variety of virulence factors enable S. suis to colonize, invade, and spread in the host, thus causing localized infections and/or systemic diseases. Enzymes catalyze almost all aspects of metabolism in living organisms. Numerous enzymes have been characterized in extensive detail in S. suis, and have shown to be involved in the pathogenesis and/or physiology of this pathogen. In this review, we describe the progress in the study of some representative enzymes in S. suis, such as ATPases, immunoglobulin-degrading enzymes, and eukaryote-like serine/threonine kinase and phosphatase, and we highlight the important role of various enzymes in the physiology and pathogenesis of this pathogen. The controversies about the current understanding of certain enzymes are also discussed here. Additionally, we provide suggestions about future directions in the study of enzymes in S. suis.

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Frequency of HPV-associated tonsillar cancer in Sweden

Journal of Clinical Oncology ◽

10.1200/jco.2009.27.15_suppl.6030 ◽

2009 ◽

Vol 27 (15_suppl) ◽

pp. 6030-6030

Author(s):

P. Attner ◽

A. Näsman ◽

L. Marklund ◽

L. Hammarstedt ◽

J. Lindholm ◽

...

Keyword(s):

Hpv 16 ◽

Hpv Dna ◽

Incidence Data ◽

Tonsillar Cancer ◽

Cancer Registry Data ◽

Comparison Results ◽

The Usa ◽

E6 And E7 ◽

Pre Treatment ◽

Almost All

6030 Background: Numerous studies has shown an increase of the incidence of tonsillar squamous cell carcinoma (SCC) both in the USA and in Sweden. This increase in incidence is despite a decreasing prevalence in smoking, a well-known risk factor for developing tonsillar cancer. The proportion of human papillomavirus (HPV) positive tonsillar SCC has also been shown to increase. This study aims to examine the incidence of tonsillar SCC and the proportion of HPV positive tonsillar SCC between 2003–2007 in the County of Stockholm, Sweden in correlation to data from 1970–2002. Methods: All patients (n = 120) diagnosed with tonsillar SCC during 2003–2007 in the County of Stockholm were included in this study. Ninety-eight pre-treatment biopsies were available and presence of HPV DNA and HPV-16 E6 and E7 mRNA were tested by PCR and RT-PCR. Incidence data between 2003–2007 for Sweden and in the County of Stockholm was obtained from the Swedish Cancer Registry. Data reported from 1970 to 2002 was also obtained for comparison. Results: HPV DNA was present in 83/98 (85%) of the tonsillar SCC biopsies from 2003–2007. Of the 77 HPV-16 positive tumors, HPV-16 E6 and E7 mRNA were found in 98% of the analyzed cases. The proportion of HPV-positive cancers had significantly increased both from 1970 to 2007 (p < 0.0001) as well from 2000 to 2007 (p < 0.01), with 68% (95% CI, 53–81) 2000–2002; 77% (95% CI, 63–87) 2003–2005; and 93% (95% CI, 82–99) 2006–2007. The incidence rate of HPV-positive tumors almost doubled each decade between 1970–2007, in parallel with a decline of HPV-negative tumors. Conclusions: Today, almost all tonsillar SCC in the County of Stockholm is HPV positive, and the incidence of HPV-positive cancers is still increasing. The data suggest that we are dealing with an epidemic of a virus-induced carcinoma, and that soon practically all tonsillar SCC will be HPV positive; a similar situation observed in cervical cancer. No significant financial relationships to disclose.

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