To attract or to repel, that is the question (for the visual cortex)

2018 ◽  
Author(s):  
Michele Fornaciai ◽  
Joonkoo Park
Keyword(s):  
Critical Role ◽  
Backward Masking ◽  
Serial Dependence ◽  
Perceptual Adaptation ◽  
Feedback Processing ◽  
Stimulus Representation ◽  
Active Stabilization ◽  
High Level ◽  
Visual Backward Masking

Despite noisy and discontinuous input, vision is remarkably stable and continuous. Recent work suggests that such a remarkable feat is enabled by an active stabilization process that integrates information over time, resulting in attractive serial dependence. However, precise mechanisms underlying serial dependence are still unknown. Here, we demonstrate that suppressing high-level modulatory signal on early cortical activity via visual backward masking completely abolishes the serial dependence effect, indicating the critical role of cortical feedback processing on serial dependence. Moreover, we show that the absence of modulatory feedback results in a robust repulsive aftereffect, as in perceptual adaptation, after only 50 ms of stimulation, indicating the presence of a local neurocomputational process for an automatic and spontaneous recalibration of the stimulus representation. These findings collectively illustrate the interplay between two contrasting cortical computational mechanisms at short timescales that serve as a basis for our perceptual experience.

scholarly journals Perception of invisible masked objects in early infancy

2021 ◽  
Author(s):  
Yusuke Nakashima ◽  
So Kanazawa ◽  
Masami K. Yamaguchi
Keyword(s):  
Visual Perception ◽  
Visual Information ◽  
Critical Role ◽  
Early Infancy ◽  
First Year ◽  
Backward Masking ◽  
Recurrent Processing ◽  
First Year Of Life ◽  
Visual Backward Masking

AbstractRecurrent loops in the visual cortex play a critical role in visual perception, which is likely not mediated by purely feedforward pathways. However, the development of recurrent loops is poorly understood. The role of recurrent processing has been studied using visual backward masking, a perceptual phenomenon in which a visual stimulus is rendered invisible by a following mask, possibly because of the disruption of recurrent processing. Anatomical studies have reported that recurrent pathways are immature in early infancy. This raises the possibility that younger infants process visual information mainly in a feedforward manner, and thus, they might be able to perceive visual stimuli that adults cannot see because of backward masking. Here, we show that infants under 7 months of age are immune to visual backward masking and that masked stimuli remain visible to younger infants while older infants cannot perceive them. These results suggest that recurrent processing is immature in infants under 7 months and that they are able to perceive objects even without recurrent processing. Our findings indicate that the algorithm for visual perception drastically changes in the second half of the first year of life.

Exosomal miR-214-5p Released from Glioblastoma Cells Modulates Inflammatory Response of Microglia after Lipopolysaccharide Stimulation through Targeting CXCR5

2019 ◽  
Vol 18 (1) ◽  
pp. 78-87 ◽  
Author(s):  
Jian-kai Yang ◽  
Hong-jiang Liu ◽  
Yuanyu Wang ◽  
Chen Li ◽  
Ji-peng Yang ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Critical Role ◽  
Luciferase Reporter ◽  
Clinical Prognosis ◽  
Direct Target ◽  
And Migration ◽  
High Level ◽  
Cxcr5 Expression ◽  
Proliferation And Migration

Background and Objective: Exosomes communicate inter-cellularly and miRNAs play critical roles in this scenario. MiR-214-5p was implicated in multiple tumors with diverse functions uncovered. However, whether miR-214-5p is mechanistically involved in glioblastoma, especially via exosomal pathway, is still elusive. Here we sought to comprehensively address the critical role of exosomal miR-214-5p in glioblastoma (GBM) microenvironment.Methods:The relative expression of miR-214-5p was determined by real-time PCR. Cell viability and migration were measured by MTT and transwell chamber assays, respectively. The secretory cytokines were measured with ELISA kits. The regulatory effect of miR-214-5p on CXCR5 expression was interrogated by luciferase reporter assay. Protein level was analyzed by Western blot.Results:We demonstrated that miR-214-5p was aberrantly overexpressed in GBM and associated with poorer clinical prognosis. High level of miR-214-5p significantly contributed to cell proliferation and migration. GBM-derived exosomal miR-214-5p promoted inflammatory response in primary microglia upon lipopolysaccharide challenge. We further identified CXCR5 as the direct target of miR-214- 5p in this setting.Conclusion:Overexpression of miR-214-5p in GBM modulated the inflammatory response in microglia via exosomal transfer.

scholarly journals Thrombomodulin Is Silenced in Malignant Mesothelioma by a Poly(ADP-ribose) Polymerase-1-mediated Epigenetic Mechanism

2011 ◽  
Vol 286 (22) ◽  
pp. 19478-19488 ◽  
Author(s):  
Linda Nocchi ◽  
Marco Tomasetti ◽  
Monica Amati ◽  
Jiri Neuzil ◽  
Lory Santarelli ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Malignant Mesothelioma ◽  
Promoter Methylation ◽  
Dna Methyltransferase ◽  
Critical Role ◽  
Gene Promoter ◽  
Epigenetic Mechanism ◽  
Heterogeneous Expression ◽  
High Level

Malignant mesothelioma (MM) is often complicated by thromboembolic episodes, with thrombomodulin (TM) playing a critical role in the anticoagulant process. Heterogeneous expression of TM has been observed in cancer, and low or no TM expression in cancer cells is associated with poor prognosis. In this study, we analyzed TM expression in biopsies of MM patients and compared them with normal mesothelial tissue. The role of DNA methylation-associated gene silencing in TM expression was investigated. To evaluate poly(ADP-ribose) polymerase-1 (PARP1) as responsible for gene promoter epigenetic modifications, nonmalignant mesothelial cells (Met-5A) and MM cells (H28) were silenced for PARP1 and the DNA methylation/acetylation-associated TM expression evaluated. A correlation between low TM expression and high level of TM promoter methylation was found in MM biopsies. Low expression of TM was restored in MM cells by their treatment with 5-aza-2′-deoxycytidine and, to a lesser extent, with trichostatin, whereas the epigenetic agents did not affect TM expression in Met-5A cells. Silencing of PARP1 resulted in a strong down-regulation of TM expression in Met-5A cells, while restoring TM expression in H28 cells. PARP1 silencing induced TM promoter methylation in Met-5A cells and demethylation in MM cells, and this was paralleled by corresponding changes in the DNA methyltransferase activity. We propose that methylation of the TM promoter is responsible for silencing of TM expression in MM tissue, a process that is regulated by PARP1.

scholarly journals The Critical Role of Biliary Candidiasis in Development of Surgical Site Infections after Pancreatoduodenectomy: Results of Prospective Study Using a Selective Culture Medium for Candida Species

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Hiroyuki Kato ◽  
Yusuke Iizawa ◽  
Kei Nakamura ◽  
Kazuyuki Gyoten ◽  
Aoi Hayasaki ◽  
...  
Keyword(s):  
Risk Factor ◽  
Candida Species ◽  
Critical Role ◽  
Significant Risk ◽  
Surgical Site Infections ◽  
Preoperative Assessment ◽  
Significant Risk Factor ◽  
High Level ◽  
New Evidence

In accordance with previous reports, the incidence of biliary candidiasis (BC) after pancreaticoduodenectomy (PD) was reported to be 0 to 5%, and the clinical significance of BC still has been elusive. In this study, we prospectively evaluated the precise incidence of BC after PD using the CHROMagar Candida plate in an attempt to elucidate whether BC has a significant impact on the clinical outcomes after PD.Patients and Method. From November 2014 to March 2016, the consecutive 51 patients who underwent PD were enrolled for this study. The bile juice was prospectively collected through the biliary stent tube on postoperative days (POD) 3, 7, and 14 and directly incubated onto the CHROMagar Candida plate for the cultivation of various Candida species. In the presence or absence of BC, we compared the incidence of SSIs.Results. The incidence of postoperative BC was 15% on POD 3, 24% on POD 7, and 39% on POD 14, respectively. Taken together, 22 patients out of 51 (43.1%) developed BC after PD. Moreover, the incidence of SSIs was significantly higher in patients with BC than in those without it (71% versus 7%, p=0.005). BC was selected as the only significant risk factor of SSIs after PD among the various risk factors. Even though a cause of BC is unknown, high level of alkaline phosphatase (cut-off line >300 IU/L) was selected as the only preoperative risk factor of the development of BC.Conclusion. We elucidated new evidence in which BC could be the independent cause of SSIs after PD and should not be recognized as just contamination artifacts. Preoperative assessment for identifying carriers of Candida species might be essential for reducing the incidence of SSIs after PD.

scholarly journals Saccharomyces cerevisiae histone Chaperones FACT and Spt6 modulate Pol II and histone occupancy genome-wide

2018 ◽  
Author(s):  
Rakesh Pathak ◽  
Priyanka Singh ◽  
Sudha Ananthakrishnan ◽  
Sarah Adamczyk ◽  
Olivia Schimmel ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Critical Role ◽  
Histone Chaperones ◽  
Strongly Correlated ◽  
Pol Ii ◽  
Chromatin Remodelers ◽  
Coding Regions ◽  
Genome Wide ◽  
High Level

ABSTRACTHistone chaperones, chromatin remodelers, and histone modifying complexes play a critical role in alleviating the nucleosomal barrier. Here, we have examined the role of two highly conserved yeast (Saccharomyces cerevisiae) histone chaperones, FACT and Spt6, in regulating transcription and histone occupancy. We show that the H3 tail contributes to the recruitment of FACT to coding sequences in a manner dependent on acetylation. We found that deleting a H3 HAT Gcn5 or mutating lysines on the H3 tail impairs FACT recruitment at ADH1 and ARG1 genes. However, deleting the H4 tail or mutating the H4 lysines failed to dampen FACT occupancy in coding regions. Additionally, we show that FACT-depletion greatly reduces Pol II occupancy in the 5’ ends genome-wide. By contrast, Spt6-depletion led to reduction in Pol II occupancy towards the 3’ end, in a manner dependent on the gene-length. Severe transcription and histone eviction defects were also observed in a strain that was impaired for Spt6 recruitment (spt6Δ202) and depleted of FACT. Importantly, the severity of the defect strongly correlated with WT Pol II occupancies at these genes, indicating critical roles of Spt6 and Spt16 in promoting high-level transcription. Collectively, our study shows cooperation, as well as redundancy between chaperones, FACT and Spt6, in regulating transcription and chromatin in coding regions of transcribed genes.

scholarly journals Perception of invisible masked objects in early infancy

2021 ◽  
Vol 118 (27) ◽  
pp. e2103040118
Author(s):  
Yusuke Nakashima ◽  
So Kanazawa ◽  
Masami K. Yamaguchi
Keyword(s):  
Visual Perception ◽  
Visual Information ◽  
Critical Role ◽  
Early Infancy ◽  
First Year ◽  
Backward Masking ◽  
Feed Forward ◽  
Recurrent Processing ◽  
First Year Of Life ◽  
Visual Backward Masking

Recurrent loops in the visual cortex play a critical role in visual perception, which is likely not mediated by purely feed-forward pathways. However, the development of recurrent loops is poorly understood. The role of recurrent processing has been studied using visual backward masking, a perceptual phenomenon in which a visual stimulus is rendered invisible by a following mask, possibly because of the disruption of recurrent processing. Anatomical studies have reported that recurrent pathways are immature in early infancy. This raises the possibility that younger infants process visual information mainly in a feed-forward manner, and thus, they might be able to perceive visual stimuli that adults cannot see because of backward masking. Here, we show that infants under 7 mo of age are immune to visual backward masking and that masked stimuli remain visible to younger infants while older infants cannot perceive them. These results suggest that recurrent processing is immature in infants under 7 mo and that they are able to perceive objects even without recurrent processing. Our findings indicate that the algorithm for visual perception drastically changes in the second half of the first year of life.

Selective Activation of Chloroplast psbD Light-Responsive Promoter and psaA/B Promoter in Transplastomic Tobacco Plants Overexpressing Arabidopsis Sigma Factor AtSIG5

2020 ◽  
Vol 27 (2) ◽  
pp. 168-175 ◽  
Author(s):  
Mikio Nozoe ◽  
Yuichi Tsunoyama ◽  
Yoko Ishizaki ◽  
Yoichi Nakahira ◽  
Takashi Shiina
Keyword(s):  
Reaction Center ◽  
Sigma Factor ◽  
Critical Role ◽  
Core Proteins ◽  
Photosynthesis Genes ◽  
High Level ◽  
Differential Transcription ◽  
D2 Protein

Background: Plastid-encoded eubacterial-type RNA polymerase (PEP) plays a critical role in the transcription of photosynthesis genes in chloroplasts. Notably, some of the reaction center genes, including psaA, psaB, psbA, and psbD genes, are differentially transcribed by PEP in mature chloroplasts. However, the molecular mechanism of promoter selection in the reaction center gene transcription by PEP is not well understood. Objective: Sigma factor proteins direct promoter selection by a core PEP in chloroplasts as well as bacteria. AtSIG5 is a unique chloroplast sigma factor essential for psbD light-responsive promoter (psbD LRP) activity. To analyze the role of AtSIG5 in chloroplast transcription in more detail, we assessed the effect of AtSIG5 hyper-expression on the transcription of plastid-encoded genes in chloroplast transgenic plants. Results: The chloroplast transgenic tobacco (CpOX-AtSIG5) accumulates AtSIG5 protein at extremely high levels in chloroplasts. Due to the extremely high-level expression of recombinant AtSIG5, most PEP holoenzymes are most likely to include the recombinant AtSIG5 in the CpOXAtSIG5 chloroplasts. Thus, we can assess the promoter preference of AtSIG5 in vivo. The overexpression of AtSIG5 significantly increased the expression of psbD LRP transcripts encoding PSII reaction center D2 protein and psaA/B operon transcripts encoding PSI core proteins. Furthermore, run-on transcription analyses revealed that AtSIG5 preferentially recognizes the psaA/B promoter, as well as the psbD LRP. Moreover, we found that psbD LRP is constitutively active in CpOX-AtSIG5 plants irrespective of light and dark. Conclusion: AtSIG5 probably plays a significant role in differential transcription of reaction center genes in mature chloroplasts.

scholarly journals THE ROLE OF FINANCE IN OUR LIVES

2021 ◽  
pp. 30-34
Author(s):  
Shahbaz Khalid
Keyword(s):  
Financial Analysis ◽  
Critical Role ◽  
Investment Risk ◽  
Financial Success ◽  
Financial Forecasting ◽  
Daily Stress ◽  
Individual Resilience ◽  
The Right ◽  
High Level

The article presents a comprehensive economics and financial analysis that plays a critical role in all areas of life. It plays an important role in individual resilience. This study includes financial and economical planning factors, revenue analysis, investment risk and financial forecasting. It includes budgeting, spending and saving. Healthy finances simply emphasize many of the goals of my life because healthy investments keep my daily stress level low, allow me to focus on doing other things, and open up opportunities to move forward. In other words, having the right level of financial success is one of the factors I measure in my life. How your financial skills help you understand how much you earn, what your monthly expenses are, and how it helps you budget for that income. The concept is that the sensitivity of investment to investment should be measured taking into account the amount of solid assets that can be used as collateral. High-level firms in the capital had high levels of investment sensitivity during the pre-crisis crisis, while post-crisis firms were less sensitive to cash flow when investing. Finance involves managing finances. KEYWORDS: finance, importance of finance, learning finance, finance and accounting, life with finance, recognizing finance, roles of finance

scholarly journals The Gendered Effects of Education and Acculturation on Older Korean Immigrants’ Cognitive Function

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 332-333
Author(s):  
Eun Young Choi ◽  
Yuri Jang ◽  
David Chiriboga
Keyword(s):  
Cognitive Function ◽  
Positive Impact ◽  
Critical Role ◽  
Health Benefit ◽  
Korean Americans ◽  
Cognitive Status ◽  
Korean Immigrants ◽  
Cognitive Health ◽  
High Level

Abstract This study advances knowledge concerning older immigrants’ cognitive health by examining the role of gender in the context of education, acculturation, and cognitive function. Guided by an emerging Gendered Process of Acculturation framework, we hypothesized that the cognitive health of men and women would benefit differently from a high level of education and acculturation. Cognitive health was measured with the Mini-Mental State Examination. Data were drawn from the Study of Older Korean Americans (SOKA), a multi-site survey of Korean Americans aged 60 and over (N = 2,061). Multivariate linear regression analyses were conducted to investigate the moderating role of gender in the effects of (1) education, (2) acculturation, and (3) the association of education and acculturation on cognitive function. Gender was found to be a significant moderator in the relationship of education and acculturation with cognitive health: the positive effect of both education and acculturation was greater among women than men. Furthermore, the three interaction among education, acculturation, and gender was significant: the positive impact of education on cognition was particularly pronounced among women with low acculturation and eliminated gender differences in cognitive status. Our findings suggest that gender plays a critical role in determining the cognitive health benefit arising from education and acculturation singularly and in concert, highlighting the vulnerability of women with low education and acculturation. These findings have implications for social interventions targeting immigrant populations.

scholarly journals Role of Complement in Host Defense against Pneumococcal Otitis Media

2009 ◽  
Vol 77 (3) ◽  
pp. 1121-1127 ◽  
Author(s):  
Vishakha Sabharwal ◽  
Sanjay Ram ◽  
Marisol Figueira ◽  
In Ho Park ◽  
Stephen I. Pelton
Keyword(s):  
Animal Model ◽  
Otitis Media ◽  
Critical Role ◽  
Invasive Disease ◽  
Complement C3 ◽  
Low Level ◽  
Fluorescence Binding ◽  
High Level ◽  
Complement Deposition

ABSTRACT Strategies to limit complement deposition on Streptococcus pneumoniae are established as virulence features for invasive disease, but their role in respiratory tract infection requires further analysis. We evaluated complement C3 protein deposition on discordant S. pneumoniae isolates of the same serotype (6A) and their capacity to cause nasopharyngeal (NP) colonization and experimental otitis media (EOM) in an animal model. We compared C3 binding to five 6A isolates from asymptomatic NP carriers with five 6A strains that caused invasive disease, and we observed less C3 (∼10-fold less fluorescence) binding to invasive isolates. We selected two high-level C3-binding carriage and two low-level C3-binding invasive 6A isolates for further study. In the EOM model, 11/12 (92%) ears challenged with a low-level C3-binding 6A strain became infected. Only 2/8 (25%) ears challenged with the discordant high-level C3-binding 6A isolate developed disease (P = 0.005). Results with the second discordant 6A isolate pair were comparable. Cobra venom factor (CoVF) treatment, which depletes C3 and consumes complement, restored virulence of the high-level C3-binding strain; 8/8 (100%) ears in CoVF-treated animals developed EOM compared to only 25% of ears in naïve animals (P = 0.007). These studies demonstrate the critical role for complement evasion in pneumococcal EOM. Colonization with carriage isolates that bound high levels of C3 caused EOM in fewer animals compared to low-level C3-binding invasive strains. Thus, limiting C3 deposition on the surface of S. pneumoniae correlates with increased incidence of EOM following NP colonization and barotrauma in the animal model.

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