scholarly journals AmpR of Stenotrophomonas maltophilia is involved in stenobactin synthesis and enhanced β-lactam resistance in an iron-depleted condition

2020 ◽  
Vol 75 (12) ◽  
pp. 3544-3551
Author(s):  
Chun-Hsing Liao ◽  
Wei-Chien Chen ◽  
Li-Hua Li ◽  
Yi-Tsung Lin ◽  
Sz-Yun Pan ◽  
...  
Keyword(s):  
Stenotrophomonas Maltophilia ◽  
Iron Homeostasis ◽  
Transcriptional Regulator ◽  
The Novel ◽  
Activity Assay ◽  
Quantitative Real Time Pcr ◽  
Iron Depletion ◽  
Promising Target ◽  
Essential Nutrient ◽  
Almost All

Abstract Background Iron is an essential nutrient for almost all aerobic organisms, including Stenotrophomonas maltophilia. Fur is the only known transcriptional regulator presumptively involved in iron homeostasis in S. maltophilia. AmpR, a LysR-type transcriptional regulator, is known to regulate β-lactamase expression and β-lactam resistance in S. maltophilia. Objectives To identify the novel regulator involved in controlling the viability of S. maltophilia in an iron-depleted condition and to elucidate the underlying regulatory mechanisms. Methods The potential regulator involved in iron homeostasis was identified by studying the cell viabilities of different regulator mutants in 2,2′-dipyridyl (DIP)-containing medium. Iron-chelating activity was investigated using the chrome azurol S (CAS) activity assay. An iron source utilization bioassay was carried out to examine utilization of different iron sources. Gene expression was determined by quantitative real-time PCR, and the Etest method was used to evaluate antibiotic susceptibility. Results Of the 14 tested mutants, the ampR mutant, KJΔAmpR, showed a growth compromise in DIP-containing medium. AmpR regulated stenobactin synthesis in an iron-depleted condition, but showed little involvement in the uptake and utilization of ferri-stenobactin and ferric citrate. AmpR was up-regulated by iron limitation and β-lactam challenge. S. maltophilia clinical isolates grown under conditions of iron depletion were generally more resistant to β-lactams compared with conditions of iron repletion. Conclusions AmpR is a dual transcriptional regulator in S. maltophilia, which regulates the β-lactam-induced β-lactamase expression and iron depletion-mediated stenobactin synthesis. AmpR is, therefore, a promising target for the development of inhibitors.

Diligent Notes on Laziness: Oblomov, Lenin and the Capitalization of Laziness

2019 ◽  
Vol 29 (1) ◽  
pp. 243-258
Keyword(s):  
Psychiatric Hospital ◽  
The Novel ◽  
Work Analysis ◽  
Main Obstacle ◽  
Almost All ◽  
Russian Linguistic ◽  
The Way

The essay investigates the phenomenon of laziness by first analyzing the opposition between laziness and the good. Both utility and the good make reference to labor. This opposition between labor and laziness is pivotal in Oblomov, Ivan Goncharov’s famous novel written in 1859. It marks a radical transition from a feudal paradigm to a capitalistic one. The two main characters in the novel are Ilya Ilyich Oblomov, a Russian, and Andrey Ivanovich Stolz, a German, who together seem to personify the contradiction between laziness and labor. But the purpose of the essay is to deconstruct that opposition. In this connection, one can cite Kazimir Malevich, who maintained that laziness is the Mother of Perfection and is always unconsciously inherent in the conscious intent to work. Analysis of the Latin concepts of otium and negotium indicates that the laziness/labor opposition may be deconstructed as a dialectic between labor and its opposite. In other words, laziness does not stand in contradiction to labor but is instead its inseparable dialectical other. In the last part of the essay, the article considers the thinking of Anatoly Peregud, a poet who spent almost all his life in a psychiatric hospital. According to Peregud, Lenin derived his pseudonym from the Russian linguistic root “len” (laziness) in order to make laziness central to communism. For his part, Lenin saw Oblomov as an emblem of the main obstacle standing in the way of communism.

scholarly journals Modelling spreading of an infection using time series by a novel family of models; fitting the time series of the confirmed cases of COVID-19 in China

2020 ◽  
Vol 9 (s1) ◽  
Author(s):  
Babak Jamshidi ◽  
Shahriar Jamshidi Zargaran ◽  
Mansour Rezaei
Keyword(s):  
Infectious Disease ◽  
Time Series ◽  
Communicable Disease ◽  
Time Series Models ◽  
Cumulative Number ◽  
The Novel ◽  
New Family ◽  
Two Samples ◽  
Almost All ◽  
Number Of Individuals

AbstractIntroductionTime series models are one of the frequently used methods to describe the pattern of spreading an epidemic.MethodsWe presented a new family of time series models able to represent the cumulative number of individuals that contracted an infectious disease from the start to the end of the first wave of spreading. This family is flexible enough to model the propagation of almost all infectious diseases. After a general discussion on competent time series to model the outbreak of a communicable disease, we introduced the new family through one of its examples.ResultsWe estimated the parameters of two samples of the novel family to model the spreading of COVID-19 in China.DiscussionOur model does not work well when the decreasing trend of the rate of growth is absent because it is the main presumption of the model. In addition, since the information on the initial days is of the utmost importance for this model, one of the challenges about this model is modifying it to get qualified to model datasets that lack the information on the first days.

scholarly journals Roles of HIF and 2-Oxoglutarate-Dependent Dioxygenases in Controlling Gene Expression in Hypoxia

Cancers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 350
Author(s):  
Julianty Frost ◽  
Mark Frost ◽  
Michael Batie ◽  
Hao Jiang ◽  
Sonia Rocha
Keyword(s):  
Gene Expression ◽  
Hypoxia Inducible Factor ◽  
Transcriptional Regulator ◽  
Hydroxylase Activity ◽  
Control Of Gene Expression ◽  
Prolyl Hydroxylases ◽  
Chromatin Organisation ◽  
Sense And Respond ◽  
Almost All ◽  
And Function

Hypoxia—reduction in oxygen availability—plays key roles in both physiological and pathological processes. Given the importance of oxygen for cell and organism viability, mechanisms to sense and respond to hypoxia are in place. A variety of enzymes utilise molecular oxygen, but of particular importance to oxygen sensing are the 2-oxoglutarate (2-OG) dependent dioxygenases (2-OGDs). Of these, Prolyl-hydroxylases have long been recognised to control the levels and function of Hypoxia Inducible Factor (HIF), a master transcriptional regulator in hypoxia, via their hydroxylase activity. However, recent studies are revealing that dioxygenases are involved in almost all aspects of gene regulation, including chromatin organisation, transcription and translation. We highlight the relevance of HIF and 2-OGDs in the control of gene expression in response to hypoxia and their relevance to human biology and health.

scholarly journals Barley Seeds miRNome Stability during Long-Term Storage and Aging

2021 ◽  
Vol 22 (9) ◽  
pp. 4315
Author(s):  
Marta Puchta ◽  
Jolanta Groszyk ◽  
Magdalena Małecka ◽  
Marek D. Koter ◽  
Maciej Niedzielski ◽  
...  
Keyword(s):  
Seed Viability ◽  
Small Rna Sequencing ◽  
The Novel ◽  
Seed Aging ◽  
Long Term Storage ◽  
Novel Mirna ◽  
Complex Biological Process ◽  
Almost All ◽  
Term Storage

Seed aging is a complex biological process that has been attracting scientists’ attention for many years. High-throughput small RNA sequencing was applied to examine microRNAs contribution in barley seeds senescence. Unique samples of seeds that, despite having the same genetic makeup, differed in viability after over 45 years of storage in a dry state were investigated. In total, 61 known and 81 novel miRNA were identified in dry seeds. The highest level of expression was found in four conserved miRNA families, i.e., miR159, miR156, miR166, and miR168. However, the most astonishing result was the lack of significant differences in the level of almost all miRNAs in seed samples with significantly different viability. This result reveals that miRNAs in dry seeds are extremely stable. This is also the first identified RNA fraction that is not deteriorating along with the loss of seed viability. Moreover, the novel miRNA hvu-new41, with higher expression in seeds with the lowest viability as detected by RT-qPCR, has the potential to become an indicator of the decreasing viability of seeds during storage in a dry state.

scholarly journals Novel Selective IDO1 Inhibitors with Isoxazolo[5,4-d]pyrimidin-4(5H)-one Scaffold

2021 ◽  
Vol 14 (3) ◽  
pp. 265
Author(s):  
Ana Dolšak ◽  
Tomaž Bratkovič ◽  
Larisa Mlinarič ◽  
Eva Ogorevc ◽  
Urban Švajger ◽  
...  
Keyword(s):  
Systematic Investigation ◽  
The Novel ◽  
Indoleamine 2,3 Dioxygenase ◽  
Tryptophan Dioxygenase ◽  
Promising Target ◽  
Synthetic Procedure ◽  
Ic50 Values ◽  
Novel Scaffold ◽  
Further Development ◽  
Micromolar Range

Indoleamine 2,3-dioxygenase 1 (IDO1) is a promising target in immunomodulation of several pathological conditions, especially cancers. Here we present the synthesis of a series of IDO1 inhibitors with the novel isoxazolo[5,4-d]pyrimidin-4(5H)-one scaffold. A focused library was prepared using a 6- or 7-step synthetic procedure to allow a systematic investigation of the structure-activity relationships of the described scaffold. Chemistry-driven modifications lead us to the discovery of our best-in-class inhibitors possessing p-trifluoromethyl (23), p-cyclohexyl (32), or p-methoxycarbonyl (20, 39) substituted aniline moieties with IC50 values in the low micromolar range. In addition to hIDO1, compounds were tested for their inhibition of indoleamine 2,3-dioxygenase 2 and tryptophan dioxygenase, and found to be selective for hIDO1. Our results thus demonstrate a successful study on IDO1-selective isoxazolo[5,4-d]pyrimidin-4(5H)-one inhibitors, defining promising chemical probes with a novel scaffold for further development of potent small-molecule immunomodulators.

scholarly journals Current Understanding of Exosomal MicroRNAs in Glioma Immune Regulation and Therapeutic Responses

2022 ◽  
Vol 12 ◽  
Author(s):  
Jinwu Peng ◽  
Qiuju Liang ◽  
Zhijie Xu ◽  
Yuan Cai ◽  
Bi Peng ◽  
...  
Keyword(s):  
Immune Regulation ◽  
Response Prediction ◽  
Cell Types ◽  
Clinicopathological Characteristics ◽  
The Novel ◽  
Multiple Cancer ◽  
Exosomal Mirnas ◽  
Multiple Cell ◽  
Almost All ◽  
Therapeutic Responses

Exosomes, the small extracellular vesicles, are released by multiple cell types, including tumor cells, and represent a novel avenue for intercellular communication via transferring diverse biomolecules. Recently, microRNAs (miRNAs) were demonstrated to be enclosed in exosomes and therefore was protected from degradation. Such exosomal miRNAs can be transmitted to recipient cells where they could regulate multiple cancer-associated biological processes. Accumulative evidence suggests that exosomal miRNAs serve essential roles in modifying the glioma immune microenvironment and potentially affecting the malignant behaviors and therapeutic responses. As exosomal miRNAs are detectable in almost all kinds of biofluids and correlated with clinicopathological characteristics of glioma, they might be served as promising biomarkers for gliomas. We reviewed the novel findings regarding the biological functions of exosomal miRNAs during glioma pathogenesis and immune regulation. Furthermore, we elaborated on their potential clinical applications as biomarkers in glioma diagnosis, prognosis and treatment response prediction. Finally, we summarized the accessible databases that can be employed for exosome-associated miRNAs identification and functional exploration of cancers, including glioma.

scholarly journals Portrayal of Bangladeshi Existentialism: “Like a Diamond in the Sky” in Context

2021 ◽  
Vol 9 (2) ◽  
pp. 51-58
Author(s):  
Moniruzzaman ◽  
Safi Ullah
Keyword(s):  
Drug Addiction ◽  
Meaning Of Life ◽  
The Novel ◽  
Dhaka City ◽  
Meaningful Life ◽  
Capacity Limitation ◽  
Existential Crisis ◽  
The People ◽  
Almost All ◽  
Power Play

Shazia Omar, a Bangladeshi novelist, depicts the less-known imagery of modern Dhaka in her debut novel “Like a Diamond in the Sky” (2009) where she portrays Bangladesh infected with depression, drug addiction, power-play, corruption and fundamentalism. Deen, the protagonist, is lost in addiction, isolated from his mother and outer world but in love with Maria, aware of the future of Bangladesh and eager to search for the meaning of life. Deen, which literally implies the earthly life in Bangla, is an existentialist who is conscious of himself and the people around him. He is aware of his capacity, limitation, existence and essence. He comments on different orders and institutions that hinder at the path of freedom, and about politicization and islamisation in Bangladesh. Not only Deen but also his widowed mother, his friend AJ, drug peddler Falani, the sergeant of the Police, Deen’s girlfriend Maria- all are conscious of their existence and essence. This novel is about a journey from a dark and aimless world to redemption, to a meaningful life. Omar presents existentialism and existential crisis as noticed in Bangladesh in her novel where almost all characters try to find the meaning of life, though in different ways. Omar says in an interview that the novel “explores their feeling of alienation in the chaotic metropolis of Dhaka city” and her protagonist struggles “to find a spiritual connection”. Before writing this novel, Shazia Omar researched in a rehab in Mumbai, visited slums of    Bangladesh and thus shaded light on the darker and less-discussed imagery of Bangladesh. “Like a Diamond in the Sky” is thoroughly examined in the light of existentialism, developed by Descartes, Kierkegaard, Sartre and Heidegger. This paper analyses how “Like a Diamond in the Sky” represents Bangladeshi existentialism, and existentialists who are conscious of existence and essence. It also discusses the observation, of Omar’s characters projected in the novel, about established orders and institutions and finally, desire for freedom and searching for meaning of life.

scholarly journals Respiratory Care in Corona

2021 ◽  
Vol 58 (2) ◽  
pp. 613-620
Author(s):  
Mustafa Amdani, Dr. Swaroopa Chakole
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Human Life ◽  
The Body ◽  
Respiratory Care ◽  
The Novel ◽  
Specific Therapy ◽  
History Of ◽  
Novel Coronavirus ◽  
Almost All ◽  
The Impact

BACKGROUND The expanse of the coronavirus disease 2019 or COVID-19 is huge. The impact is multispectral and affected almost all aspects of human life. SUMMARY Respiratory impact of the COVID-19 is the most felt and widely reported impact. As the novel coronavirus maintained its history of affecting lungs as seen previously in severe acute respiratory syndrome (SARS) outbreak. Ventilators and oxygen support system are required mostly in comorbid patients particularly amongpatientsbearing illnesses like asthma, bronchial impairment and so on. CONCLUSION More study needs to be done in order to assess the impact on the respiratory functioning of the body. Respiratory care must be including proper instruments so that more efficient result can be obtained. Research is needed to promote the invention of specific therapy for targeted action for respiratory functioning improvement.

The Impact of COVID-19 on Stock Markets

2022 ◽  
pp. 250-262
Author(s):  
Aslı Aybars ◽  
Mehtap Öner
Keyword(s):  
Literature Review ◽  
Financial Markets ◽  
Stock Returns ◽  
Empirical Studies ◽  
The Novel ◽  
The World ◽  
Fast Pace ◽  
Novel Coronavirus ◽  
Almost All ◽  
The Impact

The novel coronavirus, COVID-19, which emerged at the end of 2019 and spread to the world at a very fast pace, resulted in a pandemic affecting the finance industry besides many other industries though at varying extents. Financial markets, which can be regarded as cornerstones of each and every country's economic success, have been adversely influenced due to the fear and uncertainty arising with the emergence of the novel coronavirus at different degrees. This chapter provides a summary of a literature review based on the impact of this pandemic on stock returns and volatility in the stock exchanges of different countries and regions of the world. What has been captured as a result of this literature review is that almost all of the financial markets around the world have been influenced due to the virus. Further, industry-wise empirical studies demonstrate that not all industries are affected at the same level or even in the same direction.

scholarly journals Effect of Thidiazuron on Terpene Volatile Constituents and Terpenoid Biosynthesis Pathway Gene Expression of Shine Muscat (Vitis labrusca × V. vinifera) Grape Berries

Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2578
Author(s):  
Wu Wang ◽  
Muhammad Khalil-Ur-Rehman ◽  
Ling-Ling Wei ◽  
Niels J. Nieuwenhuizen ◽  
Huan Zheng ◽  
...  
Keyword(s):  
Volatile Compounds ◽  
Sensory Characteristics ◽  
The Novel ◽  
Terpene Biosynthesis ◽  
Grape Berries ◽  
Fruit Drop ◽  
Pathway Gene ◽  
Negative Effect ◽  
Key Genes ◽  
Almost All

Volatile compounds are considered to be essential for the flavor and aroma quality of grapes. Thidiazuron (TDZ) is a commonly used growth regulator in grape cultivation that stimulates larger berries and prevents fruit drop. This study was conducted to investigate the effect of TDZ on the production of aroma volatiles and to identify the key genes involved in the terpene biosynthesis pathways that are affected by this compound. Treatment with TDZ had a negative effect on the concentration of volatile compounds, especially on monoterpenes, which likely impacts the sensory characteristics of the fruit. The expression analysis of genes related to the monoterpenoid biosynthesis pathways confirmed that treatment with TDZ negatively regulated the key genes DXS1, DXS3, DXR, HDR, VvPNGer and VvPNlinNer1. Specifically, the expression levels of the aforementioned genes were down-regulated in almost all berry development stages in the TDZ-treated samples. The novel results from the present study can be used to aid in the development of food products which maintain the flavor quality and sensory characteristics of grape. Furthermore, these findings can provide the theoretical basis that can help to optimize the utilization of TDZ for the field production of grapes at a commercial scale.

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