scholarly journals 60 YEARS OF NEUROENDOCRINOLOGY: The hypothalamo-pituitary–gonadal axis

2015 ◽  
Vol 226 (2) ◽  
pp. T41-T54 ◽  
Author(s):  
Tony M Plant
Keyword(s):  
Gonadal Function ◽  
Neuroendocrine Control ◽  
Therapeutic Applications ◽  
Pulsatile Gnrh ◽  
Reproductive Axis ◽  
The Future ◽  
Gnrh Release ◽  
The Relationship ◽  
Ovarian Cycles

This review provides an outline of how our understanding of the neuroendocrine control of the hypothalamo-pituitary–gonadal axis has evolved since the publication of Geoffrey Harris' renowned monograph in 1955. Particular attention is directed to the neurobiology underlying pulsatile GnRH release from the hypothalamus, the neuroendocrine control of ovarian cycles, puberty and seasonality of gonadal function, and to ideas that have emerged as a result of examining the relationship between growth and the reproductive axis. The review closes with i) a brief discussion of how knowledge gained as a result of pursing the early hypotheses of Harris has led to major clinical and therapeutic applications, and ii) a personal glimpse into the future of research in this fascinating area of biology.

The relation between obesity, kisspeptin, leptin, and male fertility

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Saber Ghaderpour ◽  
Rafighe Ghiasi ◽  
Hamed Heydari ◽  
Rana Keyhanmanesh
Keyword(s):  
Male Fertility ◽  
Sperm Quality ◽  
Reproductive Potential ◽  
Reproductive Function ◽  
Leptin Resistance ◽  
Resistance Development ◽  
Reproductive Axis ◽  
Gnrh Release ◽  
Hpt Axis ◽  
The Relationship

Abstract Over the past decades, obesity and infertility in men increased in parallel, and the association between both phenomena have been examined by several researchers. despite the fact that there is no agreement, obesity appears to affect the reproductive potential of men through various mechanisms, such as changes in the hypothalamic-pituitary-testicular (HPT) axis, spermatogenesis, sperm quality and/or alteration of sexual health. Leptin is a hormone produced by the adipose tissue, and its production elevates with increasing body fat. Many studies have supported the relationship between raised leptin production and reproductive function regulation. In fact, Leptin acts on the HPT axis in men at all levels. However, most obese men are insensitive to increased production of endogenous leptin and functional leptin resistance development. Recently, it has been recommended that Kisspeptin neurons mediate the leptin’s effects on the reproductive system. Kisspeptin binding to its receptor on gonadotropin-releasing hormone (GnRH) neurons, activates the mammal’s reproductive axis and stimulates GnRH release. Increasing infertility associated with obesity is probably mediated by the Kisspeptin-GnRH pathway. In this review, the link between obesity, kisspeptin, leptin, and male fertility will be discussed.

scholarly journals The relationship between pulsatile GnRH secretion and cAMP production in immortalized GnRH neurons

2011 ◽  
Vol 300 (6) ◽  
pp. E1022-E1030 ◽  
Author(s):  
John L. Frattarelli ◽  
Lazar Z. Krsmanovic ◽  
Kevin J. Catt
Keyword(s):  
Initial Increase ◽  
Rapid Decline ◽  
Camp Production ◽  
Gnrh Secretion ◽  
Gnrh Receptors ◽  
Pulsatile Gnrh ◽  
Gnrh Neurons ◽  
Gnrh Release ◽  
High Concentrations ◽  
The Relationship

In perifused immortalized GnRH neurons (GT1–7), simultaneous measurements of GnRH and cAMP revealed that the secretory profiles for both GnRH and cAMP are pulsatile. An analysis of GnRH and cAMP pulses in 16 independent experiments revealed that 25% of pulses coincide. Inversion of the peak and nadir levels was found in 33% and random relationship between GnRH and cAMP found in 42% of analyzed pulses. The random relation between GnRH and cAMP pulse resets to synchronous after an inverse relation between pulses occurred during the major GnRH release, indicating that GnRH acts as a switching mechanism to synchronize cAMP and GnRH release in perifused GT1–7 neurons. Activation of GnRH receptors with increasing agonist concentrations caused a biphasic change in cAMP levels. Low nanomolar concentrations increased cAMP production, but at high concentrations the initial increase was followed by a rapid decline to below the basal level. Blockade of the GnRH receptors by peptide and nonpeptide antagonists generated monotonic nonpulsatile increases in both GnRH and cAMP production. These findings indicate that cAMP positively regulates GnRH secretion but does not participate in the mechanism of pulsatile GnRH release.

A Meta-Analysis of Interviews and Cognitive Ability

2013 ◽  
Vol 12 (4) ◽  
pp. 157-169 ◽  
Author(s):  
Philip L. Roth ◽  
Allen I. Huffcutt
Keyword(s):  
Cognitive Ability ◽  
Meta Analysis ◽  
Incremental Validity ◽  
Employment Interviews ◽  
Moderator Analysis ◽  
The Future ◽  
Research Questions ◽  
Meta Analyses ◽  
The Relationship

The topic of what interviews measure has received a great deal of attention over the years. One line of research has investigated the relationship between interviews and the construct of cognitive ability. A previous meta-analysis reported an overall corrected correlation of .40 ( Huffcutt, Roth, & McDaniel, 1996 ). A more recent meta-analysis reported a noticeably lower corrected correlation of .27 ( Berry, Sackett, & Landers, 2007 ). After reviewing both meta-analyses, it appears that the two studies posed different research questions. Further, there were a number of coding judgments in Berry et al. that merit review, and there was no moderator analysis for educational versus employment interviews. As a result, we reanalyzed the work by Berry et al. and found a corrected correlation of .42 for employment interviews (.15 higher than Berry et al., a 56% increase). Further, educational interviews were associated with a corrected correlation of .21, supporting their influence as a moderator. We suggest a better estimate of the correlation between employment interviews and cognitive ability is .42, and this takes us “back to the future” in that the better overall estimate of the employment interviews – cognitive ability relationship is roughly .40. This difference has implications for what is being measured by interviews and their incremental validity.

Using the alveograph in developing requirements for the quality of flour for wafer sheet production

2020 ◽  
Vol 29 (12) ◽  
pp. 52-58
Author(s):  
E.P. Meleshkina ◽  
◽  
S.N. Kolomiets ◽  
A.S. Cheskidova ◽  
◽  
...  
Keyword(s):  
Rheological Properties ◽  
Quality Indicators ◽  
Wheat Flour ◽  
Mathematical Statistics ◽  
Intended Purpose ◽  
The Future ◽  
Relationship Of ◽  
The Relationship

Objectively and reliably determined indicators of rheological properties of the dough were identified using the alveograph device to create a system of classifications of wheat and flour from it for the intended purpose in the future. The analysis of the relationship of standardized quality indicators, as well as newly developed indicators for identifying them, differentiating the quality of wheat flour for the intended purpose, i.e. for finished products. To do this, we use mathematical statistics methods.

Editor’s Pick: Regulatory and Ethical Issues in the New Era of Radiomics and Radiogenomics

EMJ Radiology ◽  
2020 ◽  
Author(s):  
Filippo Pesapane
Keyword(s):  
Ethical Issues ◽  
Medical Images ◽  
Practical Significance ◽  
Innovative Technology ◽  
New Era ◽  
Naked Eye ◽  
Disease Characteristics ◽  
The Future ◽  
Using Data ◽  
The Relationship

Radiomics is a science that investigates a large number of features from medical images using data-characterisation algorithms, with the aim to analyse disease characteristics that are indistinguishable to the naked eye. Radiogenomics attempts to establish and examine the relationship between tumour genomic characteristics and their radiologic appearance. Although there is certainly a lot to learn from these relationships, one could ask the question: what is the practical significance of radiogenomic discoveries? This increasing interest in such applications inevitably raises numerous legal and ethical questions. In an environment such as the technology field, which changes quickly and unpredictably, regulations need to be timely in order to be relevant.  In this paper, issues that must be solved to make the future applications of this innovative technology safe and useful are analysed.

Relationship Ending in the Concept of Customer Relationship Management

2015 ◽  
Vol 10 (2) ◽  
pp. 103-113
Author(s):  
Ewa Hajduk-Kasprowicz ◽  
Lech Nieżurawski
Keyword(s):  
Customer Relationship Management ◽  
Relationship Management ◽  
Professional Services ◽  
Customer Relationship ◽  
Modern Literature ◽  
Relationship Dissolution ◽  
Business Relationships ◽  
Efficient Management ◽  
The Future ◽  
The Relationship

The paper discusses the problems of fading and ending of business relationships in the sphere of professional services i.e. the phase of a relationship dissolution resulting from a client's or a firm's decision to end it. This phase includes, among others, determining the causes of the relationship dissolution and drawing conclusions for the future in order to prevent losing the most lucrative clients. Both in theory and in practice, relationship ending is perceived as something stretched in time i.e. consisting of numerous stages and influenced by numerous factors and events.The aim of the present paper is an analysis of the modern literature on the causes and mechanisms of business relationships termination in the sphere of professional services as well as indicating some possibilities of a more effective and efficient management of these relations. 

Conclusion

2017 ◽  
Author(s):  
Frédéric Grare
Keyword(s):  
United States ◽  
The United States ◽  
The Political ◽  
Slow Pace ◽  
Centre Of Gravity ◽  
The Us ◽  
The Future ◽  
Economic Interaction ◽  
The Asymmetry ◽  
The Relationship

India’s relationship with the United States remains crucial to its own objectives, but is also ambiguous. The asymmetry of power between the two countries is such that the relationship, if potentially useful, is not necessary for the United States while potentially risky for India. Moreover, the shift of the political centre of gravity of Asia — resulting from the growing rivalry between China and the US — is eroding the foundations of India’s policy in Asia, while prospects for greater economic interaction is limited by India’s slow pace of reforms. The future of India-US relations lies in their capacity to evolve a new quid pro quo in which the US will formulate its expectations in more realistic terms while India would assume a larger share of the burden of Asia’ security.

Write–Reach–Repeat

2020 ◽  
pp. 1083-1093
Author(s):  
Robin M. Boylorn
Keyword(s):  
Qualitative Research ◽  
Public Sphere ◽  
The Internet ◽  
The Public ◽  
The Future ◽  
Private And Public ◽  
The Relationship

This chapter considers the role, importance, and impact of public intellectualism on the future of qualitative research. The chapter argues that the move toward technology and the public dissemination of information via the internet requires a shift in how and what we research with an expressed intention of reaching a broader and nonacademic audience. The chapter considers the relationship between the private and public sphere, and the so-called “bastardization” of intellectualism to explain the role and rise of public intellectualism in qualitative research. By considering issues such as personal subjectivity, accountability, representation, and epistemological privilege, the chapter discusses how public contexts inform qualitative research and, conversely, how qualitative research can inform the public.

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