scholarly journals Influence of Chronic Ocular Hypertension on Emmetropia: Refractive, Structural and Functional Study in Two Rat Models

2021 ◽  
Vol 10 (16) ◽  
pp. 3697
Author(s):  
Silvia Mendez-Martinez ◽  
Teresa Martínez-Rincón ◽  
Manuel Subias ◽  
Luis E. Pablo ◽  
David García-Herranz ◽  
...  
Keyword(s):  
Ocular Hypertension ◽  
Structure And Function ◽  
Functional Study ◽  
Initial Increase ◽  
Fiber Layer ◽  
Responsible Mechanism ◽  
Progressive Myopia ◽  
Long Evans ◽  
And Function ◽  
Over Time

Chronic ocular hypertension (OHT) influences on refraction in youth and causes glaucoma in adulthood. However, the origin of the responsible mechanism is unclear. This study analyzes the effect of mild-moderate chronic OHT on refraction and neuroretina (structure and function) in young-adult Long-Evans rats using optical coherence tomography and electroretinography over 24 weeks. Data from 260 eyes were retrospectively analyzed in two cohorts: an ocular normotension (ONT) cohort (<20 mmHg) and an OHT cohort (>20 mmHg), in which OHT was induced either by sclerosing the episcleral veins (ES group) or by injecting microspheres into the anterior chamber. A trend toward emmetropia was found in both cohorts over time, though it was more pronounced in the OHT cohort (p < 0.001), especially in the ES group (p = 0.001) and males. IOP and refraction were negatively correlated at week 24 (p = 0.010). The OHT cohort showed early thickening in outer retinal sectors (p < 0.050) and the retinal nerve fiber layer, which later thinned. Electroretinography demonstrated early supranormal amplitudes and faster latencies that later declined. Chronic OHT accelerates emmetropia in Long–Evans rat eyes towards slowly progressive myopia, with an initial increase in structure and function that reversed over time.

scholarly journals Effects of Dysbiosis and Dietary Manipulation on the Digestive Microbiota of a Detritivorous Arthropod

2021 ◽  
Vol 9 (1) ◽  
pp. 148
Author(s):  
Marius Bredon ◽  
Elisabeth Depuydt ◽  
Lucas Brisson ◽  
Laurent Moulin ◽  
Ciriac Charles ◽  
...  
Keyword(s):  
Crucial Role ◽  
Structure And Function ◽  
Ecological Interactions ◽  
Dietary Manipulation ◽  
Biotic Factors ◽  
Abiotic And Biotic Factors ◽  
And Function ◽  
Multicellular Organisms ◽  
Over Time

The crucial role of microbes in the evolution, development, health, and ecological interactions of multicellular organisms is now widely recognized in the holobiont concept. However, the structure and stability of microbiota are highly dependent on abiotic and biotic factors, especially in the gut, which can be colonized by transient bacteria depending on the host’s diet. We studied these impacts by manipulating the digestive microbiota of the detritivore Armadillidium vulgare and analyzing the consequences on its structure and function. Hosts were exposed to initial starvation and then were fed diets that varied the different components of lignocellulose. A total of 72 digestive microbiota were analyzed according to the type of the diet (standard or enriched in cellulose, lignin, or hemicellulose) and the period following dysbiosis. The results showed that microbiota from the hepatopancreas were very stable and resilient, while the most diverse and labile over time were found in the hindgut. Dysbiosis and selective diets may have affected the host fitness by altering the structure of the microbiota and its predicted functions. Overall, these modifications can therefore have effects not only on the holobiont, but also on the “eco-holobiont” conceptualization of macroorganisms.

scholarly journals Alterations of the thyroid structure and function in experimental hypopinealism

2011 ◽  
Vol 57 (2) ◽  
pp. 32-35
Author(s):  
L A Bondarenko ◽  
L Iu Sergienko ◽  
N N Sotnik ◽  
A N Cherevko
Keyword(s):  
Thyroid Gland ◽  
Structural Changes ◽  
Structure And Function ◽  
Initial Increase ◽  
Histological Structure ◽  
Pituitary Thyroid Axis ◽  
Thyroid Axis ◽  
And Function ◽  
Sexually Mature

The pituitary-thyroid axis of young sexually mature rabbits kept under a 24-hour daylight photoperiod was shown to undergo phase-modulated variations of hormonal activity with its initial increase (during the first month) and subsequent progressive decrease (within 2-5 months after the onset of exposure to light). These changes correlated with the time-dependent fall in the blood T3, T4, and TSH levels. Simultaneously, the animals developed pathological changes in the histological structure of the thyroid gland similar to those in patients with secondary or tertiary hypothyroidism. It is concluded that hormonal and structural changes in the thyroid gland during long-term hypopinealism should be regarded as an experimental model of hypothyroidism of neuroendocrine origin.

Structural and functional studies of SAV1707 from Staphylococcus aureus elucidate its distinct metal-dependent activity and a crucial residue for catalysis

2021 ◽  
Vol 77 (5) ◽  
pp. 587-598
Author(s):  
Dong-Gyun Kim ◽  
Kyu-Yeon Lee ◽  
Sang Jae Lee ◽  
Seung-Ho Cheon ◽  
Yuri Choi ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Metal Binding ◽  
Binding Mode ◽  
Structure And Function ◽  
Functional Study ◽  
Functional Studies ◽  
Dependent Endonuclease ◽  
Metal Selectivity ◽  
Metal Binding Domain ◽  
And Function

The metallo-β-lactamase fold is the most abundant metal-binding domain found in two major kingdoms: bacteria and archaea. Despite the rapid growth in genomic information, most of these enzymes, which may play critical roles in cellular metabolism, remain uncharacterized in terms of structure and function. In this study, X-ray crystal structures of SAV1707, a hypothetical metalloenzyme from Staphylococcus aureus, and its complex with cAMP are reported at high resolutions of 2.05 and 1.55 Å, respectively, with a detailed atomic description. Through a functional study, it was verified that SAV1707 has Ni2+-dependent phosphodiesterase activity and Mn2+-dependent endonuclease activity, revealing a different metal selectivity depending on the reaction. In addition, the crystal structure of cAMP-bound SAV1707 shows a unique snapshot of cAMP that reveals the binding mode of the intermediate, and a key residue Phe511 that forms π–π interactions with cAMP was verified as contributing to substrate recognition by functional studies of its mutant. Overall, these findings characterized the relationship between the structure and function of SAV1707 and may provide further understanding of metalloenzymes possessing the metallo-β-lactamase fold.

Psychotic experiences, cognition, and neurodevelopment

2020 ◽  
Author(s):  
Leon Fonville ◽  
Josephine Mollon
Keyword(s):  
Brain Structure ◽  
Psychotic Disorders ◽  
Structure And Function ◽  
Elevated Risk ◽  
High Threshold ◽  
Psychotic Experiences ◽  
Cognitive Difficulties ◽  
Brain Structure And Function ◽  
And Function ◽  
Over Time

Psychotic experiences (PEs) are an expression of psychotic traits at levels below the traditionally high threshold of clinical significance and are far more prevalent in the general population. These symptoms typically dissipate over time, but the presence of PEs is associated with an elevated risk of developing a clinical psychotic disorder, such as schizophrenia. In addition, PEs show associations with neuropsychological impairment and disturbances in brain structure and function. It is thought that PEs are driven by similar neurodevelopmental and environmental mechanisms, but it is unclear how similar the underlying pathways are. This chapter will discuss the cognitive difficulties and differences in brain structure and function associated with PEs. Then, it will examine these in relation to typical neurodevelopment and the course of impairment towards clinical psychotic disorders.

scholarly journals Acetylation Preserves Retinal Ganglion Cell Structure and Function in a Chronic Model of Ocular Hypertension

2014 ◽  
Vol 55 (11) ◽  
pp. 7486 ◽  
Author(s):  
Oday Alsarraf ◽  
Jie Fan ◽  
Mohammad Dahrouj ◽  
C. James Chou ◽  
Phillip W. Yates ◽  
...  
Keyword(s):  
Ganglion Cell ◽  
Ocular Hypertension ◽  
Retinal Ganglion Cell ◽  
Cell Structure ◽  
Structure And Function ◽  
Retinal Ganglion ◽  
Chronic Model ◽  
And Function

scholarly journals A Cyclist’s Eye View of Rural Sustainability and Governance in Canada

2012 ◽  
pp. 165
Author(s):  
John Martin
Keyword(s):  
Social Networks ◽  
Rural Communities ◽  
Comparative Research ◽  
Structure And Function ◽  
Public Institutions ◽  
Rural Sustainability ◽  
And Function ◽  
Over Time

The study aims to discover and research what Canadian and Australian rural communities have in common. In both countries, rural communities are located in federations similar in structure and function, with provinces/states having considerable authority over these places. Governments are often challenged to provide equitable services to all places, especially in rural communities. Yet these communities continue to survive often facing the most challenging demographic, economic and environmental circumstances. In this comparative research, John and Alistair will ask what it is about these places, people and institutions that sustain them over time addressing the key issue of how their past, current economic fortunes, social networks and public institutions work together to ensure their sustainability.

scholarly journals Lysine Methylation of Non-Histone Proteins

2015 ◽  
pp. 1-2
Author(s):  
Byron Baron
Keyword(s):  
Protein Structure ◽  
Large Scale ◽  
Structure And Function ◽  
Cellular Biology ◽  
Lysine Methylation ◽  
Post Translational Modifications ◽  
A Cell ◽  
And Function ◽  
Small Chemical ◽  
Over Time

Proteomics, or the large-scale study of protein structure and function, has contributed greatly to our understanding of cellular biology and disease. Over time, it has become apparent that the proteome is spatially, temporally, and chemically dynamic allowing for the same protein to perform very different functions and fufill completely unrelated roles in a cell through small chemical changes. This can be described as epiproteomics (just as epigenetic are changes to DNA not encoded in the DNA sequence) and mainly covers Post-Translational Modifications (PTMs) such as phosphorylation, ubiquitination, acetylation or methylation, among over 200 or more.

Sign in / Sign up

Export Citation Format

Share Document