1,721,016 research outputs found
Endogenous transient doping: physical exercise acutely increases testosterone levels-results from a meta-analysis
Although endogenous testosterone levels are demonstrated to be affected by both acute exercise and resistance training, the dynamic regulation of androgen production after physical activity is still a matter of debate. This meta-analysis was designed to assess whether physical exercise acutely affects testosterone levels in men
Sweet, umami and bitter taste receptors: State of the art of in silico molecular modeling approaches
Background: The human taste experience is the result of five basic taste qualities, namely sweet, salty, bitter, sour and umami. Sweet, bitter, and umami are mediated by G protein-coupled receptors (GPCRs), whereas sour and salt are modulated by specialized membrane channels. Taste perception starts with the interaction between a taste-active molecule (substance) and a specialized receptor located on the taste buds at the level of the cell membrane. Once the interaction has occurred, taste receptor cells are able to transduce the information content of the chemical stimulus into nerve signals directly to the brain. Therefore, the receptor-mediated recognition of taste molecules is the first episode leading to taste perception. Scope and approach: In this review, we provide a complete overview of in silico molecular modeling techniques applied to the study of umami, sweet, and bitter taste receptors. Structure-based computational tools, usually applied to investigate the binding mode of bioactive molecules into their targets and to rationally design new drug molecules, are proven equally useful in the field of chemical senses to shed light on the molecular acknowledgment of tastants. Key findings and conclusions: The recent computational advancements in the taste research field, and particularly the computation-driven investigations of the tastant-receptor binding, provided a better understanding of the molecular mechanisms underlying food tastants’ sensing and could have an impressive contribution to the identification of new taste modulators in the future
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Polyphenol health effects on cardiovascular disorders: myth or truth? "Le basi farmacologiche dei nutraceutici"
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Real-world evidence analysis of the follicle-stimulating hormone use in male idiopathic infertility
Male idiopathic infertility remains a therapeutic challenge in the couple infertility management. In this setting, an empirical treatment with follicle-stimulating hormone (FSH) is allowed, although not recommended. Twenty-one clinical trials and four meta-analyses highlighted an overall increased pregnancy rate in case of FSH administration, but the indiscriminate FSH prescription is still unsupported by clinical evidence in idiopathic infertility. This context could represent an example in which real-world data (RWD) could add useful information. From a nationwide clinical practice survey performed in Italy, emerged the clinicians’ attitude to prescribe FSH in the case of impaired semen with a significant improvement of semen parameters, identifying FSH treatment as a therapeutic card in the real-life management. Although more robust data are still needed to optimize FSH treatment in male idiopathic infertility, RWD should be included in the body of evidence considered in healthcare decision-making
Testicular ultrasound inhomogeneity is more informative than testicular volume in fertility evaluation
Ketogenic state is able to improve testosterone serum levels - a meta-analytic approach
Background: It is widely demonstrated that obesity and hypogonadism are bi-directionally correlated, since the hypogonadism prevalence is higher in obese population, while weight loss increases testosterone serum levels. Several approaches are available to contrast weight excess, from simple dietary regimens to more complex surgical procedures. Ketogenic diets (KD) fit in this context and their application is growing year after year, aiming to improve the metabolic and weight patterns in obese patients. However, KD influence on testosterone levels is still poorly investigated.
Objectives: To systematically evaluate the potential effect of KD on testosterone levels.
Methods: A literature search was performed until April 2022 including studies investigating testosterone levels before and after KD. Secondary endpoints were body weight, estradiol and sex hormone binding globulin serum levels. Any kind of KD was considered eligible, and no specific criteria for study populations were provided.
Results: Seven studies (including eight trials) were included in the analysis, five using normocaloric KD and three very low calories KD (VLCKD). Only three studies enrolled overweight/obese men. A significant total testosterone increase was recorded after any kind of KD considering 111 patients (2.86 [0.95, 4.77], P = 0.003). This increase was more evident considering VLCKD compared to normocaloric KD (6.75 [3.31, 10.20], P < 0.001, vs 0.98 [0.08, 1.88], P = 0.030). Meta-regression analyses highlighted significant correlations between the post-KD testosterone raise with patients’ age (R-squared 36.4, P < 0.001) and weight loss (R-squared 73.6, P < 0.001).
Conclusions: Comprehensively, KD improved testosterone levels depending on both patients’ age and KD-induced weight loss. However, the lack of information in included studies on hormones of the hypothalamic-pituitary-gonadal axis prevents an exhaustive comprehension about mechanisms connecting ketosis and testosterone homeostasis
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