Biological Mechanisms of Motivation

1987 ◽  
Vol 32 (8) ◽  
pp. 705-706
Author(s):  
James R. Stellar
Keyword(s):  
Biological Mechanisms

Extraversion and Dopamine

1998 ◽  
Vol 3 (1) ◽  
pp. 37-50 ◽  
Author(s):  
Thomas H. Rammsayer
Keyword(s):  
Individual Differences ◽  
D2 Receptor ◽  
D2 Receptors ◽  
Behavioral Differences ◽  
Biological Mechanisms ◽  
Brain Dopamine ◽  
Personality Dimension ◽  
Time Performance ◽  
Reaction Time Performance ◽  
Induced Changes

Recent research suggests that individual differences in brain dopamine (DA) functioning may be related to the personality dimension of extraversion. The present study was designed to further elucidate the biological mechanisms underlying behavioral differences between extraverts and introverts. For this purpose, the differential effects of a pharmacologically induced blockade of mesolimbocortical DA D2 receptors on reaction-time performance were investigated in 24 introverted and 24 extraverted subjects. Introverts were found to be much more susceptible to pharmacologically induced changes in D2 receptor activity than extraverts. This finding provides additional experimental evidence for the notion that individual differences in D2 receptor responsivity may represent a neurobiological substratum for the personality dimension of extraversion.

Biological Mechanisms of H2S Formation in Sewer Pipes

1992 ◽  
Vol 26 (3-4) ◽  
pp. 907-914 ◽  
Author(s):  
A. Attal ◽  
M. Brigodiot ◽  
P. Camacho ◽  
J. Manem
Keyword(s):  
Suspended Solid ◽  
Urban Wastewater ◽  
Biological Mechanisms ◽  
Sewer Pipes ◽  
Sulfate Reducing ◽  
Biological Phenomena ◽  
Low Concentrations ◽  
Production Of Hydrogen ◽  
High Concentrations ◽  
Reducing Bacteria

The purpose of this study is to gain a better understanding of the biological phenomena involved in the production of hydrogen sulfide in urban wastewater (UWW) systems. It is found that the UWW itself naturally possesses the biomass needed to consume the sulfates. These heterotrophic sulfate-reducing bacteria populations, though immediately active in strict anaerobic conditions, are present only in very low concentrations in the UWW. A concentration of them was studied within the pressure pipes, in the form of deposits, and this justifies the high concentrations of sulfides measured in certain wastewater networks. There are two reasons why the ferrous sulfate used as a treatment in any wastewater networks should not cause the production of additional sulfides. Firstly, the sulfate consumption kinetics are always too slow, relative to the residence time of the water in the pipe, for all of the sulfates to be consumed anyway. Secondly, the amount of assimilable carbon, soluble carbon, and carbon from suspended solid (SS) hydrolysis is insufficient.

Development of Synchrotron Footprinting at NSLS and NSLS-II

2019 ◽  
Vol 26 (1) ◽  
pp. 55-60 ◽  
Author(s):  
Jen Bohon
Keyword(s):  
Solvent Accessibility ◽  
Biological Systems ◽  
In Vivo Studies ◽  
Aqueous Samples ◽  
Biological Mechanisms ◽  
Macromolecular Assembly ◽  
Structure And Dynamics ◽  
Synchrotron Light ◽  
Ideal Technique

Background: First developed in the 1990’s at the National Synchrotron Light Source, xray synchrotron footprinting is an ideal technique for the analysis of solution-state structure and dynamics of macromolecules. Hydroxyl radicals generated in aqueous samples by intense x-ray beams serve as fine probes of solvent accessibility, rapidly and irreversibly reacting with solvent exposed residues to provide a “snapshot” of the sample state at the time of exposure. Over the last few decades, improvements in instrumentation to expand the technology have continuously pushed the boundaries of biological systems that can be studied using the technique. Conclusion: Dedicated synchrotron beamlines provide important resources for examining fundamental biological mechanisms of folding, ligand binding, catalysis, transcription, translation, and macromolecular assembly. The legacy of synchrotron footprinting at NSLS has led to significant improvement in our understanding of many biological systems, from identifying key structural components in enzymes and transporters to in vivo studies of ribosome assembly. This work continues at the XFP (17-BM) beamline at NSLS-II and facilities at ALS, which are currently accepting proposals for use.

The emerging roles of extracellular vesicles in ovarian cancer

2020 ◽  
Vol 21 ◽  
Author(s):  
Yin-xue Wang ◽  
Yi-xiang Wang ◽  
Yi-ke Li ◽  
Shi-yan Tu ◽  
Yi-qing Wang
Keyword(s):  
Ovarian Cancer ◽  
Extracellular Vesicles ◽  
Large Scale ◽  
Current Treatment ◽  
Detection Methods ◽  
Drug Resistant ◽  
Apoptotic Bodies ◽  
Biological Mechanisms ◽  
Gynecological Malignancy ◽  
Resistance To Chemotherapy

: Ovarian cancer (OC) is one of the deadliest gynecological malignancy. Epithelial ovarian cancer (EOC) is its most common form. OC has both a poor prognosis and a high mortality rate due to the difficulties of early diagnosis, the limitation of current treatment and resistance to chemotherapy. Extracellular vesicles is a heterogeneous group of cellderived submicron vesicles which can be detected in body fluids, and it can be classified into three main types including exosomes, micro-vesicles, and apoptotic bodies. Cancer cells can produce more EVs than healthy cells. Moreover, the contents of these EVs have been found distinct from each other. It has been considered that EVs shedding from tumor cells may be implicated in clinical applications. Such as a tool for tumor diagnosis, prognosis and potential treatment of certain cancers. In this review, we provide a brief description of EVs in diagnosis, prognosis, treatment, drug-resistant of OC. Cancer-related EVs show powerful influences on tumors by various biological mechanisms. However, the contents mentioned above remain in the laboratory stage and there is a lack of large-scale clinical trials, and the maturity of the purification and detection methods is a constraint. In addition, amplification of oncogenes on ecDNA is remarkably prevalent in cancer, it may be possible that ecDNA can be encapsulated in EVs and thus detected by us. In summary, much more research on EVs needs to be perform to reveal breakthroughs in OC and to accelerate the process of its application on clinic.

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