scholarly journals Interphotoreceptor coupling: an evolutionary perspective

2021 ◽  
Author(s):  
Lorenzo Cangiano ◽  
Sabrina Asteriti
Keyword(s):  
Visual Information ◽  
Signal To Noise Ratio ◽  
Electrical Coupling ◽  
Physiological Role ◽  
Cellular Processes ◽  
Contact Points ◽  
Highly Sensitive ◽  
The Many ◽  
The Impact

AbstractIn the vertebrate retina, signals generated by cones of different spectral preference and by highly sensitive rod photoreceptors interact at various levels to extract salient visual information. The first opportunity for such interaction is offered by electrical coupling of the photoreceptors themselves, which is mediated by gap junctions located at the contact points of specialised cellular processes: synaptic terminals, telodendria and radial fins. Here, we examine the evolutionary pressures for and against interphotoreceptor coupling, which are likely to have shaped how coupling is deployed in different species. The impact of coupling on signal to noise ratio, spatial acuity, contrast sensitivity, absolute and increment threshold, retinal signal flow and colour discrimination is discussed while emphasising available data from a variety of vertebrate models spanning from lampreys to primates. We highlight the many gaps in our knowledge, persisting discrepancies in the literature, as well as some major unanswered questions on the actual extent and physiological role of cone-cone, rod-cone and rod-rod communication. Lastly, we point toward limited but intriguing evidence suggestive of the ancestral form of coupling among ciliary photoreceptors.

Structure, Function, Involvement in Diseases and Targeting of 14-3-3 Proteins: An Update

2018 ◽  
Vol 25 (1) ◽  
pp. 5-21 ◽  
Author(s):  
Ylenia Cau ◽  
Daniela Valensin ◽  
Mattia Mori ◽  
Sara Draghi ◽  
Maurizio Botta
Keyword(s):  
Protein Interactions ◽  
Molecular Mechanisms ◽  
Physiological Role ◽  
Specific Protein ◽  
Protein Protein Interactions ◽  
Cellular Processes ◽  
Protein Partners ◽  
High Sequence Homology ◽  
Small Molecule Modulators

14-3-3 is a class of proteins able to interact with a multitude of targets by establishing protein-protein interactions (PPIs). They are usually found in all eukaryotes with a conserved secondary structure and high sequence homology among species. 14-3-3 proteins are involved in many physiological and pathological cellular processes either by triggering or interfering with the activity of specific protein partners. In the last years, the scientific community has collected many evidences on the role played by seven human 14-3-3 isoforms in cancer or neurodegenerative diseases. Indeed, these proteins regulate the molecular mechanisms associated to these diseases by interacting with (i) oncogenic and (ii) pro-apoptotic proteins and (iii) with proteins involved in Parkinson and Alzheimer diseases. The discovery of small molecule modulators of 14-3-3 PPIs could facilitate complete understanding of the physiological role of these proteins, and might offer valuable therapeutic approaches for these critical pathological states.

SUBSTANTIATION OF NECESSITY OF APPLICATION OF PHOSPHOLIPIDS IN THE PRODUCTION OF FUNCTIONAL FOODSTUFFS

2018 ◽  
Author(s):  
Н.Н. КОРНЕН ◽  
С.А. КАЛМАНОВИЧ ◽  
Т.А. ШАХРАЙ ◽  
Е.П. ВИКТОРОВА
Keyword(s):  
Nutritional Status ◽  
Dietary Supplements ◽  
Physiological Role ◽  
Regulatory Function ◽  
Medical Sciences ◽  
Cellular Processes ◽  
Level Of Knowledge ◽  
Protective Fabrics ◽  
Technological University

Проведен анализ современных научных представлений о роли фосфолипидов (ФЛ) в обеспечении функционирования биомембран и их регуляторной функции в важнейших клеточных процессах. Из ФЛ состоит 50% печени, 1/3 мозговых изолирующих и защитных тканей, окружающих головной и спинной мозг. По рекомендациям РАМН, физиологическая потребность взрослого человека в ФЛ составляет 5–7 г/сут. Согласно проведенным исследованиям, в пищевом статусе населения РФ дефицит ФЛ составляет от 50 до 80%. Показано, что современный уровень знаний о физиологической роли ФЛ способствует созданию и внедрению в производство фосфолипидных продуктов на основе ФЛ и фосфолипидных БАД на основе растительных лецитинов, употребление которых может нормализовать пищевой статус. Дано описание фосфолипидных продуктов и БАД серии Тонус (Супер-Тонус, Фито-Тонус, Тонус-Плюс) и серии Витол (Витол, Витол-Холин и Витол-ФЭИ), разработанных учеными Кубанского государственного технологического университета. Показаны возможности применения растительных лецитинов, фосфолипидных продуктов и БАД на их основе в качестве многофункциональных рецептурных компонентов при производстве пищевых продуктов функционального и специализированного назначения. The analysis of modern scientific ideas about the role of phospholipids (FL) in ensuring the functioning of biomembranes and their regulatory function in the most important cellular processes is carried out. So, 50% of a liver, 1/3 brain isolating and protective fabrics surrounding a brain and spinal cord consist of FL. According to the recommendations of the Russian Academy of Medical Sciences, the physiological need of an adult in FL is 5–7 g/day. According to the conducted studies, in the nutritional status of the Russian population, the deficit of FL is from 50 to 80%. It is shown that the current level of knowledge about the physiological role of FL contributes to the creation and introduction of phospholipid products based on FL and phospholipid supplements on the basis of vegetable lecithins, the use of which can normalize the nutritional status. The description of phospholipid products and dietary supplements developed by scientists of the Kuban State Technological University of the Tonus series (Super Tonus, Phyto Tonus, Tonus Plus) and the Vitol series (Vitol, Vitol Kholin and Vitol FEI) is given. The possibilities of using vegetable lecithins, phospholipid products and dietary supplements on their basis are shown as multifunctional prescription components in the production of functional and specialized food products.

Marriage and Sexual Relations in the New Testament World

2014 ◽  
Author(s):  
William Loader
Keyword(s):  
Roman Society ◽  
Greco Roman ◽  
The Social ◽  
The New Testament ◽  
The Common ◽  
The Many ◽  
Marital Sex ◽  
The Impact ◽  
Common Understanding

After a brief overview of the social context and role of marriage and sexuality in Jewish and Greco-Roman cultures, the chapter traces the impact of the Genesis creation narratives, positively and negatively, on how marriage and sexuality were seen both in the present and in depictions of hope for the future. Discussion of pre-marital sex, incest, intermarriage, polygyny, divorce, adultery, and passions follows. It then turns to Jesus’ reported response to divorce, arguing that the prohibition sayings should be read as assuming that sexual intercourse both effects permanent union and severs previous unions, thus making divorce after adultery mandatory, the common understanding and legal requirement in both Jewish and Greco-Roman society of the time. It concludes by noting both the positive appreciation of sex and marriage, grounded in belief that they are God’s creation, and the many dire warnings against sexual wrongdoing, including adulterous attitudes and uncontrolled passions.

scholarly journals Immunotoxicity of Xenobiotics in Fish: A Role for the Aryl Hydrocarbon Receptor (AhR)?

2021 ◽  
Vol 22 (17) ◽  
pp. 9460
Author(s):  
Helmut Segner ◽  
Christyn Bailey ◽  
Carolina Tafalla ◽  
Jun Bo
Keyword(s):  
Immune System ◽  
Aryl Hydrocarbon Receptor ◽  
Disease Susceptibility ◽  
Immune Cell ◽  
Physiological Role ◽  
Immune Gene ◽  
Immune Systems ◽  
Aryl Hydrocarbon ◽  
The Impact

The impact of anthropogenic contaminants on the immune system of fishes is an issue of growing concern. An important xenobiotic receptor that mediates effects of chemicals, such as halogenated aromatic hydrocarbons (HAHs) and polyaromatic hydrocarbons (PAHs), is the aryl hydrocarbon receptor (AhR). Fish toxicological research has focused on the role of this receptor in xenobiotic biotransformation as well as in causing developmental, cardiac, and reproductive toxicity. However, biomedical research has unraveled an important physiological role of the AhR in the immune system, what suggests that this receptor could be involved in immunotoxic effects of environmental contaminants. The aims of the present review are to critically discuss the available knowledge on (i) the expression and possible function of the AhR in the immune systems of teleost fishes; and (ii) the impact of AhR-activating xenobiotics on the immune systems of fish at the levels of immune gene expression, immune cell proliferation and immune cell function, immune pathology, and resistance to infectious disease. The existing information indicates that the AhR is expressed in the fish immune system, but currently, we have little understanding of its physiological role. Exposure to AhR-activating contaminants results in the modulation of numerous immune structural and functional parameters of fish. Despite the diversity of fish species studied and the experimental conditions investigated, the published findings rather uniformly point to immunosuppressive actions of xenobiotic AhR ligands in fish. These effects are often associated with increased disease susceptibility. The fact that fish populations from HAH- and PAH-contaminated environments suffer immune disturbances and elevated disease susceptibility highlights that the immunotoxic effects of AhR-activating xenobiotics bear environmental relevance.

scholarly journals Evidence-gathering in police interviews

2019 ◽  
Vol 10 (1) ◽  
pp. 9-31 ◽  
Author(s):  
Luna Filipović
Keyword(s):  
Police Officers ◽  
Investigative Interviewing ◽  
Police Interviews ◽  
Legal Context ◽  
Highly Sensitive ◽  
Communication Difficulties ◽  
Evidence Gathering ◽  
Police Interrogations ◽  
The Many

Abstract In this paper I discuss the many complexities that police officers have to deal with in their communication with suspects. Investigative interviewing is a very complex communicative situation in itself, with a number of different psychological and sociological variables at play during each interview. In addition, suspect interviews bring about an additional dimension of complexity, which is driven by the fact that a basic principle of conversation, cooperation (Grice 1975) is often not respected and is sometimes severely and purposefully violated, for example when suspects are guilty and want to obscure that very fact or when they believe that their situation would worsen if they cooperated with the police. A further layer of complexity is added when the interviews are carried out via an interpreter, where the fact that the officer and the suspect speak different languages during the interview creates additional barriers to straightforward communication. In the present paper, I identify a number of points at which communication difficulties are encountered in this highly sensitive legal context. For this purpose, I analyse authentic interview datasets provided by two UK police constabularies, and also make comparisons with examples from transcripts of authentic US police interrogations. In addition, I highlight the issues that arise when professional interpretation is not available and when bilingual police officers assume the dual role of investigator-interpreter. Finally, I suggest possible solutions that can help remove the hurdles standing in the way of efficient and accurate gathering of communication evidence.

scholarly journals Molecular Hydrogen, a Neglected Key Driver of Soil Biogeochemical Processes

2019 ◽  
Vol 85 (6) ◽  
Author(s):  
Sarah Piché-Choquette ◽  
Philippe Constant
Keyword(s):  
Energy Requirement ◽  
Keystone Species ◽  
Physiological Role ◽  
Atp Synthesis ◽  
Potential Contribution ◽  
Biogeochemical Processes ◽  
Individual Level ◽  
C Cycling ◽  
The Impact

ABSTRACTThe atmosphere of the early Earth is hypothesized to have been rich in reducing gases such as hydrogen (H2). H2has been proposed as the first electron donor leading to ATP synthesis due to its ubiquity throughout the biosphere as well as its ability to easily diffuse through microbial cells and its low activation energy requirement. Even today, hydrogenase enzymes enabling the production and oxidation of H2are found in thousands of genomes spanning the three domains of life across aquatic, terrestrial, and even host-associated ecosystems. Even though H2has already been proposed as a universal growth and maintenance energy source, its potential contribution as a driver of biogeochemical cycles has received little attention. Here, we bridge this knowledge gap by providing an overview of the classification, distribution, and physiological role of hydrogenases. Distribution of these enzymes in various microbial functional groups and recent experimental evidence are finally integrated to support the hypothesis that H2-oxidizing microbes are keystone species driving C cycling along O2concentration gradients found in H2-rich soil ecosystems. In conclusion, we suggest focusing on the metabolic flexibility of H2-oxidizing microbes by combining community-level and individual-level approaches aiming to decipher the impact of H2on C cycling and the C-cycling potential of H2-oxidizing microbes, via both culture-dependent and culture-independent methods, to give us more insight into the role of H2as a driver of biogeochemical processes.

The Oxford Handbook of Hope

2017 ◽  
Keyword(s):  
Current Knowledge ◽  
Physical And Mental Health ◽  
Comprehensive Overview ◽  
Future Directions ◽  
Theoretical Perspectives ◽  
The Many ◽  
The Impact ◽  
Made In

The Oxford Handbook of Hope provides a comprehensive overview of current knowledge regarding the science and practice of hope. Hope has long been a topic of interest to philosophers and the general public, but it was only in recent decades that hope became a focus of psychological science. Rick Snyder defined hope as a cognitive trait that helps individuals to identify and pursue goals and consists of two components: pathways, the perceived capacity to identify strategies necessary to achieve goals, and agency, the willpower or motivation to pursue those pathways to achieve goals. Hope has become one of most robust and promising topics in the burgeoning field of positive psychology. This book reviews the progress that has been made in the past 25 years regarding the origins and influence of hope. Topics covered include current theoretical perspectives on how best to define hope and how it is distinct from related constructs, current best practices for measuring and quantifying hope, interventions and strategies for promoting hope across different settings and the lifespan, the impact that hope has on many dimensions and domains of physical and mental health, and the many ways and contexts in which hope promotes resilience and positive functioning. Experts in the field both review what is currently known about the role of hope in different domains and identify topics and questions that can help to guide the next decade of research. The handbook concludes with a collaborative vision on the future directions of the science of hope.

Pathophysiology of β2-glycoprotein I in antiphospholipid syndrome

Lupus ◽  
2010 ◽  
Vol 19 (4) ◽  
pp. 379-384 ◽  
Author(s):  
E. Matsuura ◽  
L. Shen ◽  
Y. Matsunami ◽  
N. Quan ◽  
M. Makarova ◽  
...  
Keyword(s):  
Vascular Disease ◽  
Antiphospholipid Syndrome ◽  
Mechanism Of Action ◽  
Antiphospholipid Antibodies ◽  
Physiological Role ◽  
Therapeutic Strategies ◽  
Physiological Functions ◽  
Glycoprotein I ◽  
The Impact

Since β2-glycoprotein I (β2GPI) was described as the major antigenic target for antiphospholipid antibodies, many studies have focused their attention to the physiological role of β2GPI and anti-β2GPI antibodies on autoimmune-mediated thrombosis. Studies reporting the physiological role of β2GPI have been numerous, but the exact mechanism of action(s) has yet to be completely determined. β2GPI’s epitopes for anti-β2GPI autoantibodies have been characterized, however, not all of the heterogeneous anti-β2GPI antibodies are pathogenic. The pathophysiologic role of β2GPI has been reported in the fields of coagulation, fibrinolysis, angiogenesis, and atherosclerosis. Our understanding of the impact of β2GPI, its metabolites and autoantibodies to β2GPI on these physiological functions may contribute to the development of better therapeutic strategies to treat and prevent autoimmune-mediated atherothrombotic vascular disease. Lupus (2010) 19, 379—384.

scholarly journals Targeted disruption of G protein-coupled bile acid receptor 1 (Gpbar1/M-Bar) in mice

2006 ◽  
Vol 191 (1) ◽  
pp. 197-205 ◽  
Author(s):  
Takaharu Maruyama ◽  
Kenichi Tanaka ◽  
Jun Suzuki ◽  
Hiroyuki Miyoshi ◽  
Naomoto Harada ◽  
...  
Keyword(s):  
Bile Acid ◽  
G Protein ◽  
Physiological Role ◽  
Wild Type ◽  
Fat Accumulation ◽  
Acid Receptor ◽  
Bile Acid Receptor ◽  
The Impact ◽  
G Protein Coupled

G protein-coupled bile acid receptor 1 (Gpbar1/M-Bar) is a novel G protein-coupled receptor for bile acid. Tissue distribution and cell-type specificity of Gpbar1 mRNA suggest a potential role for the receptor in the endocrine system; however, the precise physiological role of Gpbar1 still remains to be elucidated. To investigate the role of Gpbar1 in vivo, the Gpbar1 gene was disrupted in mice. In homozygous mice, total bile acid pool size was significantly decreased by 21–25% compared with that of the wild-type mice, suggesting that Gpbar1 contributes to bile acid homeostasis. In order to assess the impact of Gpbar1 deficiency in bile acid homeostasis more precisely, Gpbar1 homozygous mice were fed a high-fat diet for 2 months. As a result, female Gpbar1 homozygous mice showed significant fat accumulation with body weight gain compared with that of the wild-type mice. These findings were also observed in heterozygous mice to the same extent. Although the precise mechanism for fat accumulation in female Gpbar1 homozygous mice remains to be addressed, these data indicate that Gpbar1 is a potential new player in energy homeostasis. Thus, Gpbar1-deficient mice are useful in elucidating new physiological roles for Gpbar1.

scholarly journals Aldehyde oxidation in human placenta. Purification and properties of 1-pyrroline-5-carboxylate dehydrogenase

1988 ◽  
Vol 256 (2) ◽  
pp. 461-467 ◽  
Author(s):  
J Farrés ◽  
P Julià ◽  
X Parés
Keyword(s):  
Human Placenta ◽  
Deae Cellulose ◽  
Physiological Role ◽  
Total Activity ◽  
Molar Ratio ◽  
Distribution Study ◽  
Purification And Properties ◽  
Highly Sensitive ◽  
Aldehyde Oxidation

The human placenta contains a considerable amount of 1-pyrroline-5-carboxylate dehydrogenase (23 +/- 6 micrograms/g; n = 12), about 25% of the concentration present in liver. The enzyme is the only form in placenta that oxidizes short- and medium-chain aldehydes, which facilitates its purification from this organ. It can be purified to homogeneity by successive chromatographies on DEAE-cellulose, 5′-AMP-Sepharose and Sephacryl S-300. From 500 g of tissue, about 2.1 units of enzyme can be obtained with a 12% yield. Placental 1-pyrroline-5-carboxylate dehydrogenase is a dimer of Mr-63,000 subunits. It exhibits a pI of 6.80-6.65, and is specific for 1-pyrroline-5-carboxylate, the cyclic form of glutamate gamma-semialdehyde (Km = 0.17 mM, kcat. = 870 min-1), although it also oxidizes short-chain aliphatic aldehydes such as propionaldehyde (Km = 24 mM, kcat. = 500 min-1). These properties are very close to those of the liver enzyme, indicating a strong similarity between the enzyme forms from both organs. The enzyme is highly sensitive to temperature, showing 50% inhibition after incubation for 0.8 min at 45 degrees C or after 23 min at 25 degrees C. It is irreversibly inhibited by disulfiram, and a molar ratio inhibitor: enzyme of 60:1 produced 50% inhibition after incubation for 10 min. A subcellular-distribution study indicates that the enzyme is located in two compartments: the mitochondria, with 60% of the total activity, and the cytosol, with 40% activity. The physiological role of the enzyme in placental amino acid metabolism is discussed.

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