ESTROGEN SYNTHESIS IN NORMAL AND HYPOGONADAL MEN: QUANTITATIVE STUDIES ON THE PRECURSOR ROLE OF TESTOSTERONE

1966 ◽  
Vol 44 (6) ◽  
pp. 971-977 ◽  
Author(s):  
B. J. Epstein ◽  
M. C. Raheja ◽  
E. Frow ◽  
W. I. Morse
Keyword(s):  
New Method ◽  
Plasma Testosterone ◽  
Quantitative Studies ◽  
Estrogen Production ◽  
Estrogen Synthesis ◽  
17Β Estradiol ◽  
Specific Activities ◽  
Normal Men

Tritiated (7α-3H) testosterone was injected intravenously into normal and hypogonadal men after which all urine was collected for 5 days. The urine was assayed for estrone, 17β-estradiol, estriol, and 3H associated with these fractions by the new method of Blair and co-workers. The specific activities of the urinary estrogen fractions from the normal men were sufficiently low to warrant the conclusion that there were other sources of estrogen production in addition to the plasma testosterone pool. It was also shown that the higher specific activities observed in this laboratory during a previous study, similar except that the Bauld method was used for the assays, were due to radiochemical impurities in the final estrogen fractions. The hypogonadal men had low urinary estrogen levels but there was no evidence of gross abnormality in the metabolism of 3H-testosterone to 3H-estrogens in this group.In two out of three instances, 1,2-3H-testosterone injection produced less 3H-labeled urinary estrogen than 7-3H-testosterone injection. This finding suggested that 3H was lost either from the C-1 or the C-2 position during the biosynthesis of estradiol from testosterone.

scholarly journals Sex, Pramipexole and Tiagabine Affect Behavioral and Hormonal Response to Traumatic Stress in a Mouse Model of PTSD

2021 ◽  
Vol 12 ◽  
Author(s):  
Natalia Malikowska-Racia ◽  
Kinga Salat ◽  
Joanna Gdula-Argasinska ◽  
Piotr Popik
Keyword(s):  
Mouse Model ◽  
Conditioned Fear ◽  
Plasma Corticosterone ◽  
Plasma Testosterone ◽  
Potential Capacity ◽  
17Β Estradiol ◽  
Plasma Hormones ◽  
Hpa Response ◽  
Prolonged Stress

Posttraumatic stress disorder (PTSD) has been associated with abnormal regulation of the hypothalamic-pituitary-adrenal gland axis (HPA). Women demonstrate a more robust HPA response and are twice as likely to develop PTSD than men. The role of sex hormones in PTSD remains unclear. We investigated whether post-trauma chronic treatment with the GABA-ergic agent tiagabine and dopamine-mimetic pramipexole affected the behavioral outcome and plasma levels of corticosterone, testosterone, or 17β-estradiol in female and male mice. These medications were investigated due to their potential capacity to restore GABA-ergic and dopaminergic deficits in PTSD. Animals were exposed to a single prolonged stress procedure (mSPS). Following 13 days treatment with tiagabine (10 mg/kg) or pramipexole (1 mg/kg) once daily, the PTSD-like phenotype was examined in the fear conditioning paradigm. Plasma hormones were measured almost immediately following the conditioned fear assessment. We report that the exposure to mSPS equally enhanced conditioned fear in both sexes. However, while males demonstrated decreased plasma corticosterone, its increase was observed in females. Trauma elevated plasma testosterone in both sexes, but it had no significant effects on 17β-estradiol. Behavioral manifestation of trauma was reduced by pramipexole in both sexes and by tiagabine in females only. While neither compound affected corticosterone in stressed animals, testosterone levels were further enhanced by tiagabine in females. This study shows sex-dependent efficacy of tiagabine but not pramipexole in a mouse model of PTSD-like symptoms and a failure of steroid hormones’ levels to predict PTSD treatment efficacy.

SUPRESSION OF ANDROGEN AND OESTROGEN PRODUCTION IN NORMAL MEN

1972 ◽  
Vol 70 (2) ◽  
pp. 342-350 ◽  
Author(s):  
M. A. Kirschner ◽  
D. W. R. Knorr
Keyword(s):  
Urine Sample ◽  
Plasma Testosterone ◽  
Low Level ◽  
Normal Men

ABSTRACT An attempt was made to suppress production of androgens and oestrogens in normal men by administering large doses of exogenous androgens and corticoids. After 5 days of 40 mg fluoxymesterone qd, plasma testosterone concentrations decreased from 509 to 73 ng/100 ml (85%); on adding 8 mg qd of dexamethasone, there was a further decrease to 45 ng/100 ml. Androstenedione concentrations were decreased equally by fluoxymesterone and corticoids. To monitor the suppressive effects of exogenous steroids, urinary LH was followed serially by radioimmunoassay, and decreased to only 40% of control levels after 5 days of fluoxymesterone, with no further suppression noted on adding dexamethasone. Nanogram quantities of steroidal metabolites were not adsorbed by kaolin extraction of urine, thus enabling gonadotrophins (kaolin extract) and low-level steroids (supernate) to be measured in the same urine sample. Urinary oestrone and oestradiol excretion decreased during 5 days of fluoxymesterone, and continued to fall when dexamethasone was added. In no case was oestrone or oestradiol excretion, urinary LH or plasma androgens completely suppressed by large doses of fluoxymesterone alone, or in combination with large doses of dexamethasone.

Children’s Lives and Deaths in Merovingian Gaul

2020 ◽  
pp. 185-213
Author(s):  
Émilie Perez
Keyword(s):  
Social Identity ◽  
Age Groups ◽  
New Method ◽  
Recent Analysis ◽  
Age And Gender ◽  
The Past ◽  
And Gender ◽  
Grave Goods

The role of children in Merovingian society has long been downplayed, and the study of their graves and bones has long been neglected. However, during the past fifteen years, archaeologists have shown growing interest in the place of children in Merovingian society. Nonetheless, this research has not been without challenges linked to the nature of the biological and material remains. Recent analysis of 315 children’s graves from four Merovingian cemeteries in northern Gaul (sixth to seventh centuries) allows us to understand the modalities of burial ritual for children. A new method for classifying children into social age groups shows that the type, quality, quantity, and diversity of grave goods were directly correlated with the age of the deceased. They increased from the age of eight and particularly around the time of puberty. This study discusses the role of age and gender in the construction and expression of social identity during childhood in the Merovingian period.

scholarly journals A Potential Role and Contribution of Androgens in Placental Development and Pregnancy

Life ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 644
Author(s):  
Agata M. Parsons ◽  
Gerrit J. Bouma
Keyword(s):  
Fetal Development ◽  
Fetal Loss ◽  
Membrane Receptors ◽  
Placental Development ◽  
Placental Function ◽  
Fetal Physiology ◽  
Estrogen Synthesis ◽  
And Function ◽  
Pregnancy Disorders

Successful pregnancy requires the establishment of a highly regulated maternal–fetal environment. This is achieved through the harmonious regulation of steroid hormones, which modulate both maternal and fetal physiology, and are critical for pregnancy maintenance. Defects in steroidogenesis and steroid signaling can lead to pregnancy disorders or even fetal loss. The placenta is a multifunctional, transitory organ which develops at the maternal–fetal interface, and supports fetal development through endocrine signaling, the transport of nutrients and gas exchange. The placenta has the ability to adapt to adverse environments, including hormonal variations, trying to support fetal development. However, if placental function is impaired, or its capacity to adapt is exceeded, fetal development will be compromised. The goal of this review is to explore the relevance of androgens and androgen signaling during pregnancy, specifically in placental development and function. Often considered a mere precursor to placental estrogen synthesis, the placenta in fact secretes androgens throughout pregnancy, and not only contains the androgen steroid nuclear receptor, but also non-genomic membrane receptors for androgens, suggesting a role of androgen signaling in placental function. Moreover, a number of pregnancy disorders, including pre-eclampsia, gestational diabetes, intrauterine growth restriction, and polycystic ovarian syndrome, are associated with abnormal androgen levels and androgen signaling. Understanding the role of androgens in the placenta will provide a greater understanding of the pathophysiology of pregnancy disorders associated with androgen elevation and its consequences.

scholarly journals A new method for identifying the role of marital preferences at shaping marriage patterns

2021 ◽  
pp. 1-27
Author(s):  
Anna Naszodi ◽  
Francisco Mendonca
Keyword(s):  
Contingency Table ◽  
Transformation Method ◽  
New Method ◽  
Marriage Patterns ◽  
The Us ◽  
Analytical Properties ◽  
The Matrix ◽  
Transformation Methods

Abstract We develop a method which assumes that marital preferences are characterized either by the scalar-valued measure proposed by Liu and Lu, or by the matrix-valued generalized Liu–Lu measure. The new method transforms an observed contingency table into a counterfactual table while preserving its (generalized) Liu–Lu value. After exploring some analytical properties of the new method, we illustrate its application by decomposing changes in the prevalence of homogamy in the US between 1980 and 2010. We perform this decomposition with two alternative transformation methods as well where both methods capture preferences differently from Liu and Lu. Finally, we use survey evidence to support our claim that out of the three considered methods, the new transformation method is the most suitable for identifying the role of marital preferences at shaping marriage patterns. These data are also in favor of measuring assortativity in preferences à la Liu and Lu.

scholarly journals Studies on the Role of the are a Gene in the Regulation of Nitrogen Catabolism in Aspergillus nidulans

1975 ◽  
Vol 28 (3) ◽  
pp. 301 ◽  
Author(s):  
MJ Hynes
Keyword(s):  
Nitrogen Source ◽  
Aspergillus Nidulans ◽  
Carbon Sources ◽  
Nitrogen Sources ◽  
Selection Methods ◽  
Growth Responses ◽  
Dominance Relationships ◽  
Regulatory Circuits ◽  
Specific Activities

Mutants of Apergillus nidulanswith lesions in a gene, areA (formerly called amdT), have been isolated by a variety of different selection methods. The areA mutants show a range of pleiotropic growth responses to a number of compounds as sole nitrogen sources, but are normal in utilization of carbon sources. The levels of two amidase enzymes as well as urease have been investigated in the mutants and have been shown to be affected by this gene. Most of the areA mutants have much lower amidase-specific activities when grown in ammonium-containing medium, compared with mycelium incubated in medium la9king a nitrogen source. Some of the areA. mutants do not show derepression of urease upon relief of ammonium repression. The dominance relationships of areA alleles have been investigated in� heterozygous diploids, and these studies lend support to the proposal that areA codes for a positively acting regulatory product. One of the new areA alleles is partially dominant to areA + and areA102. This may be a result of negative complementation or indicate that areA has an additional negative reiuIatory function. Investigation.of various amdR; areA double mutants has led to the conclusion that amdR and areA participate in independent regulatory circuits in the control of acetamide utilizatiol1. Studies on an amdRc; areA.double mutant indicate that areA is involved in derepression of acetamidase upon relief of ammo.nium repression.

Managing multichannel coordination in retail banking: the influence of customer participation

2006 ◽  
Vol 24 (5) ◽  
pp. 327-345 ◽  
Author(s):  
Loïc Plé
Keyword(s):  
Organizational Design ◽  
Retail Banking ◽  
Customer Participation ◽  
Content Type ◽  
Quantitative Studies ◽  
Retail Banks ◽  
The Impact ◽  
Depth Interviews

PurposeThe purpose of this research is to explore the combining of marketing and organizational literature. This paper seeks to evaluate the relationships between multichannel coordination and customer participation, as seen through the lens of potential customer opportunism. It aims at showing the impact of this opportunism on the organizational design of multiple channels structures.Design/methodology/approachThe research reports on an exploratory case study in a French retail bank. A total of 25 in‐depth interviews were conducted, and the use of other sources enabled data triangulation.FindingsThe results show first that an increase in the number of distribution channels is liable to favor customer opportunistic behavior. To counter this, the bank mainly relies on impersonal coordination modes. An emerging result highlights the role of the customer as a “perceptual filter” between the different channels of employees.Research limitations/implicationsCustomer opportunism is studied via channels employees perceptions. An investigation using a customer survey may help to better understand this construct, e.g. to identify its antecedents, and to measure it precisely. Moreover, further qualitative and/or quantitative studies with larger sample sizes are needed to try and generalize these results.Practical implicationsIt is recommended not to forget that customers can facilitate or hinder multichannel coordination. Retail banks have the power to use them conveniently, provided that they are fully conscious of the scope of the “partial employee” role played by the customer.Originality/valueThis paper broadens understanding of how multichannel distribution structures are coordinated, and in a way belies traditional organizational design literature. The emerging result gives birth to the concept of “reversed interactive marketing”, which has interesting theoretical and practical repercussions.

scholarly journals Prolactin and Male Fertility: The Long and Short Feedback Regulation

2009 ◽  
Vol 2009 ◽  
pp. 1-13 ◽  
Author(s):  
M. K. Gill-Sharma
Keyword(s):  
Chromatin Condensation ◽  
Feedback Regulation ◽  
Pituitary Hormones ◽  
Feedback Mechanism ◽  
Reproductive Hormones ◽  
Male Rats ◽  
Normal Men

In the last 20 years, a pituitary-hypothalamus tissue culture system with intact neural and portal connections has been developed in our lab and used to understand the feedback mechanisms that regulate the secretions of adenohypophyseal hormones and fertility of male rats. In the last decade, several in vivo rat models have also been developed in our lab with a view to substantiate the in vitro findings, in order to delineate the role of pituitary hormones in the regulation of fertility of male rats. These studies have relied on both surgical and pharmacological interventions to modulate the secretions of gonadotropins and testosterone. The interrelationship between the circadian release of reproductive hormones has also been ascertained in normal men. Our studies suggest that testosterone regulates the secretion of prolactin through a long feedback mechanism, which appears to have been conserved from rats to humans. These studies have filled in a major lacuna pertaining to the role of prolactin in male reproductive physiology by demonstrating the interdependence between testosterone and prolactin. Systemic levels of prolactin play a deterministic role in the mechanism of chromatin condensation during spermiogenesis.

scholarly journals Characterizing Highly Benefited Patients in Randomized Clinical Trials

2017 ◽  
Vol 13 (1) ◽  
Author(s):  
Vivek Charu ◽  
Paul B. Rosenberg ◽  
Lon S. Schneider ◽  
Lea T. Drye ◽  
Lisa Rein ◽  
...  
Keyword(s):  
Randomized Clinical Trials ◽  
Controlled Trial ◽  
New Method ◽  
Usual Model ◽  
Randomized Controlled ◽  
Working Model ◽  
Large Numbers ◽  
High Benefit ◽  
Two Stages

AbstractPhysicians and patients may choose a certain treatment only if it is predicted to have a large effect for the profile of that patient. We consider randomized controlled trials in which the clinical goal is to identify as many patients as possible that can highly benefit from the treatment. This is challenging with large numbers of covariate profiles, first, because the theoretical, exact method is not feasible, and, second, because usual model-based methods typically give incorrect results. Better, more recent methods use a two-stage approach, where a first stage estimates a working model to produce a scalar predictor of the treatment effect for each covariate profile; and a second stage estimates empirically a high-benefit group based on the first-stage predictor. The problem with these methods is that each of the two stages is usually agnostic about the role of the other one in addressing the clinical goal. We propose a method that characterizes highly benefited patients by linking model estimation directly to the particular clinical goal. It is shown that the new method has the following two key properties in comparison with existing approaches: first, the meaning of the solution with regard to the clinical goal is the same, and second, the value of the solution is the best that can be achieved when using the working model as a predictor, even if that model is incorrect. In the Citalopram for Agitation in Alzheimer’s Disease (CitAD) randomized controlled trial, the new method identifies substantially larger groups of highly benefited patients, many of whom are missed by the standard method.

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