precise role
Recently Published Documents


TOTAL DOCUMENTS

368
(FIVE YEARS 123)

H-INDEX

49
(FIVE YEARS 8)

2021 ◽  
Author(s):  
Ralf Duerr ◽  
Dacia Dimartino ◽  
Christian Marier ◽  
Paul Zappile ◽  
Samuel Levine ◽  
...  

AbstractIn 2021, Delta has become the predominant SARS-CoV-2 variant worldwide. While vaccines effectively prevent COVID-19 hospitalization and death, vaccine breakthrough infections increasingly occur. The precise role of clinical and genomic determinants in Delta infections is not known, and whether they contribute to increased rates of breakthrough infections compared to unvaccinated controls. Here, we show a steep and near complete replacement of circulating variants with Delta between May and August 2021 in metropolitan New York. We observed an increase of the Delta sublineage AY.25, its spike mutation S112L, and nsp12 mutation F192V in breakthroughs. Delta infections were associated with younger age and lower hospitalization rates than Alpha. Delta breakthroughs increased significantly with time since vaccination, and, after adjusting for confounders, they rose at similar rates as in unvaccinated individuals. Our data indicate a limited impact of vaccine escape in favor of Delta’s increased epidemic growth in times of waning vaccine protection.


Ramus ◽  
2021 ◽  
Vol 50 (1-2) ◽  
pp. 68-86
Author(s):  
Jacob Abolafia

In addition to its many famous innovations in popular government, the Athenian democracy seems to have also experimented with another, more ambivalent political institution familiar to modern societies—penal incarceration. In recent years, there has been renewed debate over the precise role of imprisonment in Athens, as an increasing number of voices, including Marcus Folch in this volume, make the case that imprisonment was an important point of contact between criminal punishment and democratic politics and society in Athens.


Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3241
Author(s):  
Kaja Urbańska ◽  
Arkadiusz Orzechowski

For many years, it was thought that ATG5 and ATG7 played a pivotal role in autophagy, and that the knockdown of one of these genes would result in its inhibition. However, cells with ATG5 or ATG7 depletion still generate autophagic vacuoles with mainly trans-Golgi-originated isolation membranes and do not die. This indicates that autophagy can occur via ATG5/ATG7-independent alternative autophagy. Its molecular mechanism differs from that of the canonical pathway, including inter alia the phosphorylation of ULK1, and lack of LC3 modifications. As the alternative autophagy pathway has only recently been described, little is known of its precise role; however, a considerable body of evidence suggests that alternative autophagy participates in mitochondrion removal. This review summarizes the latest progress made in research on alternative autophagy and describes its possible molecular mechanism, roles and methods of detection, and possible modulators. There is a need for further research focused on types of autophagy, as this can elucidate the functioning of various cell types and the pathogenesis of human and animal diseases.


2021 ◽  
Author(s):  
Manish Kumar ◽  
Simone Piccinin ◽  
Varadharajan Srinivasan

The oxygen evolution reaction (OER) activity of pristine NiOOH is enhanced by doping with Fe. However, the precise role of Fe is still being debated. Here, we use the first-principles DFT+U approach to study three different types of active sites: one on pristine and the other two on Fe-doped NiOOH monolayers to account for the direct and indirect roles of Fe. To compare the activity of the active sites, we consider two mechanisms of OER based on the source of O-O bond formation. Our results show that the mechanism involving the coupling of lattice oxygen is generally more favorable than water nucleophilic attack on lattice oxygen. On doping with Fe, the overpotential of NiOOH is reduced by 0.33 V in excellent agreement with experimental findings. Introducing Fe at active sites results in different potential determining steps (PDS) in the two mechanisms, whereas Ni sites in pristine and Fe-doped NiOOH have the same PDS regardless of the mechanism. The Fe sites not only have the lowest overpotential but also decrease the overpotential for Ni sites.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Haiqin Jiang ◽  
Lemuel Tsang ◽  
Hongsheng Wang ◽  
Changhong Liu

Interferon-induced protein 44-like (IFI44L) gene is a type I interferon-stimulated gene (ISG) that plays a critical role in antiviral activity and constitutes a promising diagnostic marker. However, its precise role and function in tuberculosis have not been unveiled. This study showed that IFI44L acts as an antimicrobial target and positive modulator in human macrophages. Knockdown of IFI44L led to increased Mycobacterium tuberculosis intracellular survival. Moreover, IFI44L was significantly upregulated, and it restricted the intracellular survival of M. tuberculosis H37Rv strains at 72 h after rifampicin treatment. Individuals with cutaneous tuberculosis (CTB) were found to have significantly higher IFI44L expression after 6 months of rifampicin therapy than after only 1 month. These results demonstrated that IFI44L induced positive regulation and clearance of M. tuberculosis from human macrophages. This antimicrobial activity of IFI44L makes it a possible target for therapeutic applications against M. tuberculosis.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiaoya Lu ◽  
Hanchuang Zhu ◽  
Yi Chen ◽  
Yue Wu ◽  
Dongsheng Zhang ◽  
...  

AbstractPeriodontitis, one of the most common chronic inflammatory diseases, affects the quality of life. Osteogenesis plays an important role in the disease. There is a connection between hydrogen sulfide (H2S) and periodontitis, but according to the study has been published, the precise role of H2S in inflammation remains in doubt. The main reason for the lack of research is that H2S is an endogenous gasotransmitter, difficult to discern through testing. So, we synthesized a novel fluorescence probe which can detect H2S in vitro. By using the novel H2S fluorescence probe, we found that H2S changes in osteoblasts mainly by cystathionine-γ-lyase, and H2S increases under LPS stimulation. H2S could be a potential marker for diagnosis of inflammatory diseases of bone, and might help deepen studies of the changes of H2S level and promote the progression on the researches about pathogenesis of periodontitis.


2021 ◽  
Author(s):  
Ahmed A. Ramadan ◽  
Karthick Mayilsamy ◽  
Andrew R. McGill ◽  
Anandita Ghosh ◽  
Marc A. Giulianotti ◽  
...  

Spike glycoproteins of almost all enveloped viruses are known to undergo post-translational attachment of palmitic acid moieties. The precise role of such palmitoylation of the spike protein in membrane fusion and infection is not completely understood. Here, we report that palmitoylation of the first five cysteine residues of the c-terminal cysteine-rich domain of the SARS-CoV-2 spike are indispensable for infection, and palmitoylation deficient spike mutants are defective in trimerization and subsequent membrane fusion. The DHHC9 palmitoyltransferase interacts with and palmitoylates the spike protein in the ER and Golgi, and knockdown of DHHC9 results in reduced fusion and infection of SARS-CoV-2. Two bis-piperazine backbone-based DHHC9 inhibitors inhibit SARS-CoV-2 spike protein palmitoylation and the resulting progeny virion particles released are defective in fusion and infection. This establishes these palmitoyltransferase inhibitors as potential new intervention strategies against SARS-CoV-2.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Shaozhi Li ◽  
Alberto Nocera ◽  
Umesh Kumar ◽  
Steven Johnston

AbstractAlthough many experiments imply that oxygen orbitals play an essential role in the high-temperature superconducting cuprates, their precise role in collective spin and charge excitations and superconductivity is not yet fully understood. Here, we study the doping-dependent dynamical spin and charge structure factors of single and multi-orbital (pd) models for doped one-dimensional corner-shared spin-chain cuprates using several numerically exact methods. In doing so, we determine the orbital composition of the collective spin and charge excitations of cuprates, with important implications for our understanding of these materials. For example, we observe a particle-hole asymmetry in the orbital-resolved charge excitations, which is directly relevant to resonant inelastic x-ray scattering experiments and not captured by the single-band Hubbard model. Our results imply that one must explicitly include the oxygen degrees of freedom in order to fully understand some experimental observations on cuprate materials.


2021 ◽  
Vol 12 ◽  
Author(s):  
Anneke Vedder ◽  
Margeret S. Stroebe ◽  
Henk A.W. Schut ◽  
Kathrin Boerner ◽  
Jeffrey E. Stokes ◽  
...  

The role of loneliness in the bereavement experience has been reported as substantial, with the death of a close person leaving a considerable void in the life of the bereaved. Yet, there is lack of agreement about its precise role and, notably, whether loneliness should be included as a core symptom for diagnosis of grief complications. The ongoing threat of heightened social isolation due to the COVID-19 pandemic underlines the need to understand the impact of loneliness, and to accurately chart its prevalence, intensity, duration, and associated difficulties in the context of bereavement. Assessment issues are central to this endeavor. In this article, we review the scientific literature to examine how loneliness after bereavement has been operationalized and measured. Sixty-three articles analyzing 51 independent datasets were reviewed. Results show major disparities: approximately half of the projects assessed loneliness by means of one of two validated scales (spanning different versions); the remainder included only single- or few-item measures. Diverse instructions, content and answer categories were used. While one size does not fit all, awareness of assessment options and dis/advantages may aid selection of the most appropriate measure, to suit the goals of a particular study and the specific groups under investigation. Our conclusion is that, in selecting a loneliness measure, health care professionals should come to their own well-informed decision, aided by the information provided in our review.


Biomolecules ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1345
Author(s):  
Li Cheng ◽  
Jiaying Liu ◽  
Zhong Chen

Histamine does not only modulate the immune response and inflammation, but also acts as a neurotransmitter in the mammalian brain. The histaminergic system plays a significant role in the maintenance of wakefulness, appetite regulation, cognition and arousal, which are severely affected in neuropsychiatric disorders. In this review, we first briefly describe the distribution of histaminergic neurons, histamine receptors and their intracellular pathways. Next, we comprehensively summarize recent experimental and clinical findings on the precise role of histaminergic system in neuropsychiatric disorders, including cell-type role and its circuit bases in narcolepsy, schizophrenia, Alzheimer’s disease, Tourette’s syndrome and Parkinson’s disease. Finally, we provide some perspectives on future research to illustrate the curative role of the histaminergic system in neuropsychiatric disorders.


Sign in / Sign up

Export Citation Format

Share Document