Macaque vision after magnocellular lateral geniculate lesions

AbstractIbotenic-acid lesions of the magnocelluar portion of the macaque lateral geniculate nucleus were used to examine the role of the M-cell pathway in spatio-temporal contrast sensitivity. A lesion was place in layer 1 of the lateral geniculate of each of two monkeys. Physiological mapping in one animal demonstrated that the visual-field locus of the lesion was on the horizontal meridian, approximately 6 deg in the temporal field. Visual thresholds were tested monocularly in the contralateral eye, and fixation locus was monitored with a scleral search coil to control the retinal location of the test target.Three threshold measures were clearly disrupted by the magnocellular lesions. Contrast sensitivity for a 1 cycle/deg grating that drifted at 10 Hz was reduced from about twofold greater than, to about the same as, that for 10-Hz counterphase modulated gratings. Sensitivity for a very low spatial frequency (Gaussian blob), 10-Hz flickering stimulus was reduced so severely that no threshold could be measured. In addition, flicker resolution was greatly reduced at lower modulation depths (0.22), but not at higher depths (1.0). Two of the measured thresholds were unaffected by the lesions. Contrast sensitivity for 2 cycle/deg stationary gratings remained intact, and little or no effect on sensitivity was found for 1 cycle/deg, 10-Hz counterphase modulated gratings.Together, these results suggest that the magnocellular pathway makes little contribution to visual sensitivity at low to moderate temporal frequencies. On the other hand, some contribution to detection sensitivity is evident at lower spatial and high temporal frequencies, especially for drifting stimuli. It appears that a major role of the magnocellular pathway may be to provide input to cortical mechanisms sensitive to rapid visual motion.

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A Proteomic Study on the Personalized Protein Corona of Liposomes. Relevance for Early Diagnosis of Pancreatic DUCTAL Adenocarcinoma and Biomarker Detection

Journal of Nanotheranostics ◽

10.3390/jnt2020006 ◽

2021 ◽

Vol 2 (2) ◽

pp. 82-93

Author(s):

Luca Digiacomo ◽

Francesca Giulimondi ◽

Daniela Pozzi ◽

Alessandro Coppola ◽

Vincenzo La Vaccara ◽

...

Keyword(s):

Pancreatic Cancer ◽

Early Diagnosis ◽

Pancreatic Ductal Adenocarcinoma ◽

Protein Corona ◽

Detection Sensitivity ◽

Ductal Adenocarcinoma ◽

Protein Biomarkers ◽

Ca 19.9 ◽

Proteomic Study

Due to late diagnosis, high incidence of metastasis, and poor survival rate, pancreatic cancer is one of the most leading cause of cancer-related death. Although manifold recent efforts have been done to achieve an early diagnosis of pancreatic cancer, CA-19.9 is currently the unique biomarker that is adopted for the detection, despite its limits in terms of sensitivity and specificity. To identify potential protein biomarkers for pancreatic ductal adenocarcinoma (PDAC), we used three model liposomes as nanoplatforms that accumulate proteins from human plasma and studied the composition of this biomolecular layer, which is known as protein corona. Indeed, plasma proteins adsorb on nanoparticle surface according to their abundance and affinity to the employed nanomaterial, thus even small differences between healthy and PDAC protein expression levels can be, in principle, detected. By mass spectrometry experiments, we quantified such differences and identified possible biomarkers for PDAC. Some of them are already known to exhibit different expressions in PDAC proteomes, whereas the role of other relevant proteins is still not clear. Therefore, we predict that the employment of nanomaterials and their protein corona may represent a useful tool to amplify the detection sensitivity of cancer biomarkers, which may be used for the early diagnosis of PDAC, with clinical implication for the subsequent therapy in the context of personalized medicine.

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Reduced direction discrimination sensitivity in visual motion adaptation, and the role of perceptual learning

Vision Research ◽

10.1016/j.visres.2021.02.002 ◽

2021 ◽

Vol 185 ◽

pp. 111-122

Author(s):

Sabrina Karjack ◽

Gennady Erlikhman ◽

Zili Liu

Keyword(s):

Perceptual Learning ◽

Visual Motion ◽

Motion Adaptation ◽

Direction Discrimination

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MYC-targeted WDR4 promotes proliferation, metastasis, and sorafenib resistance by inducing CCNB1 translation in hepatocellular carcinoma

Cell Death and Disease ◽

10.1038/s41419-021-03973-5 ◽

2021 ◽

Vol 12 (7) ◽

Author(s):

Peng Xia ◽

Hao Zhang ◽

Kequan Xu ◽

Xiang Jiang ◽

Meng Gao ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Epithelial Mesenchymal Transition ◽

P53 Protein ◽

Rna Modifications ◽

M Cell ◽

Mesenchymal Transition ◽

Akt Phosphorylation ◽

Repeat Domain ◽

Cell Cycle Transition

AbstractHepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. However, there still remains a lack of effective diagnostic and therapeutic targets for this disease. Increasing evidence demonstrates that RNA modifications play an important role in the progression of HCC, but the role of the N7-methylguanosine (m7G) methylation modification in HCC has not been properly evaluated. Thus, the goal of the present study was to investigate the function and mechanism of the m7G methyltransferase WD repeat domain 4 (WDR4) in HCC as well as its clinical relevance and potential value. We first verified the high expression of WDR4 in HCC and observed that upregulated WDR4 expression increased the m7G methylation level in HCC. WDR4 promoted HCC cell proliferation by inducing the G2/M cell cycle transition and inhibiting apoptosis in addition to enhancing metastasis and sorafenib resistance through epithelial-mesenchymal transition (EMT). Furthermore, we observed that c-MYC (MYC) can activate WDR4 transcription and that WDR4 promotes CCNB1 mRNA stability and translation to enhance HCC progression. Mechanistically, we determined that WDR4 enhances CCNB1 translation by promoting the binding of EIF2A to CCNB1 mRNA. Furthermore, CCNB1 was observed to promote PI3K and AKT phosphorylation in HCC and reduce P53 protein expression by promoting P53 ubiquitination. In summary, we elucidated the MYC/WDR4/CCNB1 signalling pathway and its impact on PI3K/AKT and P53. Furthermore, the result showed that the m7G methyltransferase WDR4 is a tumour promoter in the development and progression of HCC and may act as a candidate therapeutic target in HCC treatment.

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The Role of Spatio-Temporal Information to Govern the COVID-19 Pandemic: A European Perspective

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi10030166 ◽

2021 ◽

Vol 10 (3) ◽

pp. 166

Author(s):

Hartmut Müller ◽

Marije Louwsma

Keyword(s):

European Union ◽

Spatial Distribution ◽

Spatial Information ◽

National Level ◽

Temporal Information ◽

The European Union ◽

Member States ◽

Heavy Burden ◽

Spatio Temporal

The Covid-19 pandemic put a heavy burden on member states in the European Union. To govern the pandemic, having access to reliable geo-information is key for monitoring the spatial distribution of the outbreak over time. This study aims to analyze the role of spatio-temporal information in governing the pandemic in the European Union and its member states. The European Nomenclature of Territorial Units for Statistics (NUTS) system and selected national dashboards from member states were assessed to analyze which spatio-temporal information was used, how the information was visualized and whether this changed over the course of the pandemic. Initially, member states focused on their own jurisdiction by creating national dashboards to monitor the pandemic. Information between member states was not aligned. Producing reliable data and timeliness reporting was problematic, just like selecting indictors to monitor the spatial distribution and intensity of the outbreak. Over the course of the pandemic, with more knowledge about the virus and its characteristics, interventions of member states to govern the outbreak were better aligned at the European level. However, further integration and alignment of public health data, statistical data and spatio-temporal data could provide even better information for governments and actors involved in managing the outbreak, both at national and supra-national level. The Infrastructure for Spatial Information in Europe (INSPIRE) initiative and the NUTS system provide a framework to guide future integration and extension of existing systems.

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Role of the Vermal Cerebellum in Visually Guided Eye Movements and Visual Motion Perception

Annual Review of Vision Science ◽

10.1146/annurev-vision-091718-015000 ◽

2019 ◽

Vol 5 (1) ◽

pp. 247-268 ◽

Cited By ~ 1

Author(s):

Peter Thier ◽

Akshay Markanday

Keyword(s):

Eye Movements ◽

Motion Perception ◽

Visual Motion ◽

Cerebellar Nuclei ◽

Visually Guided ◽

Past Performance ◽

Visual Motion Perception ◽

Oculomotor Vermis ◽

Retinal Information

The cerebellar cortex is a crystal-like structure consisting of an almost endless repetition of a canonical microcircuit that applies the same computational principle to different inputs. The output of this transformation is broadcasted to extracerebellar structures by way of the deep cerebellar nuclei. Visually guided eye movements are accommodated by different parts of the cerebellum. This review primarily discusses the role of the oculomotor part of the vermal cerebellum [the oculomotor vermis (OMV)] in the control of visually guided saccades and smooth-pursuit eye movements. Both types of eye movements require the mapping of retinal information onto motor vectors, a transformation that is optimized by the OMV, considering information on past performance. Unlike the role of the OMV in the guidance of eye movements, the contribution of the adjoining vermal cortex to visual motion perception is nonmotor and involves a cerebellar influence on information processing in the cerebral cortex.

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Role of intrathalamic inhibition on the spatial frequency tuning of neurons in the lateral geniculate nucleus of the cat

Neuroscience Research ◽

10.1016/j.neures.2009.09.477 ◽

2009 ◽

Vol 65 ◽

pp. S106

Author(s):

Akihiro Kimura ◽

Satoshi Shimegi ◽

Shin-ichiro Hara ◽

Masahiro Okamoto ◽

Hiromichi Sato

Keyword(s):

Spatial Frequency ◽

Lateral Geniculate Nucleus ◽

Frequency Tuning ◽

Spatial Frequency Tuning ◽

Lateral Geniculate

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From Loschmidt daemons to time-reversed waves

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2015.0156 ◽

2016 ◽

Vol 374 (2069) ◽

pp. 20150156 ◽

Cited By ~ 8

Author(s):

Mathias Fink

Keyword(s):

Wave Propagation ◽

Time Reversal ◽

Degrees Of Freedom ◽

Point Of View ◽

Propagation Time ◽

Reversal Invariance ◽

Spatial Boundary ◽

Dual Approaches ◽

Spatio Temporal

Time-reversal invariance can be exploited in wave physics to control wave propagation in complex media. Because time and space play a similar role in wave propagation, time-reversed waves can be obtained by manipulating spatial boundaries or by manipulating time boundaries. The two dual approaches will be discussed in this paper. The first approach uses ‘time-reversal mirrors’ with a wave manipulation along a spatial boundary sampled by a finite number of antennas. Related to this method, the role of the spatio-temporal degrees of freedom of the wavefield will be emphasized. In a second approach, waves are manipulated from a time boundary and we show that ‘instantaneous time mirrors’, mimicking the Loschmidt point of view, simultaneously acting in the entire space at once can also radiate time-reversed waves.

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A geographical analysis of the first wave of Covid-19 with reference to highland and lowland regions of India

National Geographical Journal of India ◽

10.48008/ngji.1776 ◽

2021 ◽

Vol 67 (3) ◽

pp. 263-281

Author(s):

Bindhy Wasini Pandey ◽

◽

Yuvraj Singh ◽

Usha Rani ◽

Roosen Kumar ◽

...

Keyword(s):

Infectious Diseases ◽

Temporal Pattern ◽

Regional Disparity ◽

Healthcare Facilities ◽

Indian Himalayan Region ◽

Pollution Levels ◽

Extensive Coverage ◽

The World ◽

Spatio Temporal

The issue of health has become a major concern in recent years as a result of extensive coverage of media reporting outbreaks of diseases and the spread of deadly infectious diseases around the world. There has been a growing concern over the accessibility and affordability of healthcare facilities. The spread of the ongoing pandemic COVID-19 has been felt all over the world. However, the rate of infection varies across certain regions of the world. There exists intra-regional disparity as well. Recent research shows that there are latitudinal and altitudinal variations in the spread of the COVID-19. This paper studies variation of infection COVID-19 across the highlands of the Indian Himalayan Region (IHR) and the lowland areas in India. The paper also examines the role of geographical spaces in the spread of coronavirus in these regions. The study indicates that place-based effects (altitude, temperature, pollution levels, etc.) on health can be seen in a variety of ways; therefore, locational issues are very important for addressing health questions. The paper also analyses the Spatio-temporal pattern of the COVID-19 pandemic in the study area to understand the nature of the disease in different locations.

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