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Cecilia Høst Ramlau-hansen - One of the best experts on this subject based on the ideXlab platform.
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Is age at puberty associated with semen quality and reproductive hormones in young adult life
Asian journal of andrology, 2017Co-Authors: Lea L B Lauridsen, Jørn Olsen, Henrik Støvring, Linn Håkonsen Arendt, Cecilia Høst Ramlau-hansenAbstract:The evidence is scarce on the association between age at puberty and semen quality. A cohort of 320 Danish men aged 18-21 years enrolled in the "Healthy Habits for Two" birth cohort provided self-reported data on pubertal indicators and delivered semen and blood samples. The results indicated an association between older age at pubertal development and lower semen quality and altered reproductive hormones concentrations as measured in young adult life. Men who had their first Nocturnal Emission, start of pubic hair growth and first voice break episode when older than 15 years had 37.0%, 45.0% and 32.7% lower sperm concentration; 37.8%, 44.2% and 29.1% lower total sperm count; 7.4%, 13.4% and 15.3% lower testosterone concentration; and 21.3%, 1.5% and 3.7% lower inhibin B concentration, respectively, compared with the men who were younger than 13 years at their first pubertal indicators. Only few of the results were statistically significant, but similar tendencies were seen in several of the reproductive parameters suggesting an association between the timing of pubertal development and reproductive health later in life.
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In utero exposure to alcohol and puberty in boys: a pregnancy cohort study
BMJ open, 2014Co-Authors: Linn Berger Håkonsen, Jørn Olsen, Ane Marie Thulstrup, Mette Louise Brath-lund, Marie Louise Hounsgaard, Andreas Ernst, Bodil Hammer Bech, Cecilia Høst Ramlau-hansenAbstract:Objectives: Epidemiological studies have raised concerns about the reproductive consequences of in utero exposure to alcohol. Maternal lifestyle factors have been associated with altered pubertal development, but the impact of prenatal alcohol exposure on male puberty is unknown. Thus, the objective was to explore whether prenatal alcohol exposure alters pubertal development in boys. Setting: Follow-up of a Danish pregnancy cohort. Participants: Sons (N=2522) of women who were enrolled in a Danish pregnancy cohort between 1984 and 1987. Primary and secondary outcome measures: Indicators of pubertal development, assessed by age at first Nocturnal Emission, voice break, acne and regular shaving. Results: We found a tendency towards a later age at first Nocturnal Emission and voice break following in utero exposure to binge drinking. Boys exposed to ≥5 binge drinking episodes during pregnancy experienced their first Nocturnal Emission 7.3 months (95% CI −2.8 to 17.4) later and voice break 4.9 months (95% CI −0.6 to 10.4) later than the unexposed boys. Results for average weekly alcohol consumption were in the same direction, but differences were smaller and not statistically significant. Conclusions: We found no strong support for the hypothesis that in utero exposure to weekly alcohol consumption is a risk factor for altered pubertal development, but a tendency towards delayed pubertal development among boys exposed to binge drinking during fetal life was observed. Longitudinal studies, with data collected as children go through puberty, are needed to explore this further.
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Maternal pre-pregnancy body mass index and pubertal development among sons
Andrology, 2013Co-Authors: M L Hounsgaard, Linn Berger Håkonsen, Ane Marie Thulstrup, Anne Vested, Jens Peter Bonde, Ellen A. Nohr, Cecilia Høst Ramlau-hansenAbstract:Summary Maternal overweight and obesity in pregnancy has been associated with earlier age of menarche in daughters as well as reduced semen quality in sons. We aimed at investigating pubertal development in sons born by mothers with a high body mass index (BMI). The study included 2522 sons of mothers that during pregnancy in 1984–1987 were enrolled in a mother–child cohort and gave information on their pre-pregnancy height and weight from which we calculated their BMI. Information on sons' pubertal development, assessed by age when starting regular shaving, voice break, acne and first Nocturnal Emission, was obtained from web-based questionnaires in 2005, when sons were 18–21 years old. Multiple linear regression analyses showed that sons of obese mothers on average started to shave regularly 8.3 (95% confidence interval: 2.5–14.0) months earlier than sons of normal weight mothers. For the three other indicators of pubertal development, results also indicated earlier pubertal development among sons of obese mothers. After excluding sons of underweight mothers in a subanalysis, we observed an inverse trend between maternal pre-pregnancy BMI and age at regular shaving, acne and first Nocturnal Emission. In conclusion, maternal pre-pregnant obesity may be related to earlier timing of pubertal milestones among sons. More research, preferably based on prospectively collected information about pubertal development, is needed to draw firm conclusions.
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Maternal cigarette smoking during pregnancy and pubertal development in sons. A follow-up study of a birth cohort
Andrology, 2013Co-Authors: Linn Berger Håkonsen, Jørn Olsen, Henrik Støvring, Anja Ernst, Ane Marie Thulstrup, Jin Liang Zhu, Anshu Shrestha, Cecilia Høst Ramlau-hansenAbstract:Summary Epidemiological studies have raised concern about the reproductive consequences of prenatal cigarette smoking exposure, possibly affecting semen quality and onset of pubertal development of the offspring. The aim of this study was to further investigate pubertal development in young men exposed to cigarette smoking in foetal life. In a Danish pregnancy cohort, information on maternal smoking during pregnancy was available from questionnaires administered in 1984–1987, and information on pubertal development, assessed by age at first Nocturnal Emission, acne, voice break and regular shaving, was obtained from a follow-up questionnaire administered in 2005 to the young men (age: 18–21). We found no significant association between prenatal cigarette smoking exposure and earlier onset of puberty, but we did observe a tendency towards earlier age of first Nocturnal Emission, acne and voice break, indicating an accelerated age of pubertal development. Men exposed to ≥15 cigarettes/day had 3.1 months (95% CI: −6.4; 0.2) earlier age at acne and 2.2 months (95% CI: −7.3; 3.0) earlier age at first Nocturnal Emission, 1.2 months (95% CI: −4.6; 2.2) earlier age at voice break, however, 1.3 months (95% CI: −1.6; 4.3) later age at regular shaving, compared with unexposed men. Prenatal cigarette smoking exposure may induce an earlier age at onset of puberty in young men, but larger studies with prospectively collected data on pubertal development are needed to explore this hypothesis further.
Birgit Piechulla - One of the best experts on this subject based on the ideXlab platform.
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Influence of Green Leaf Herbivory by Manduca sexta on Floral Volatile Emission by Nicotiana suaveolens
Plant physiology, 2008Co-Authors: Uta Effmert, Claudia Dinse, Birgit PiechullaAbstract:Plants have to cope with various abiotic and biotic impacts as a consequence of changing environments, which can impair their ability to sexually reproduce. The main objective of this study was to investigate whether green leaf herbivory, having one of the most hazardous biotic impacts, would have any direct effect on the production and Emission of floral volatiles because volatiles are known to play a crucial role in pollination. Nicotiana suaveolens plants were challenged with Manduca sexta feeding on leaves, and alterations in the quality and quantity of the floral blend, shifts in Emission patterns, and changes in expression patterns of the floral benzoic/salicylic acid carboxyl-methyltransferase were monitored in noninfested and infested plants. Leaves responded to larval feeding by herbivory-induced diurnal Emission of semiochemicals, whereas the Emission of floral volatiles remained unchanged in comparison to the noninfested control. Neither the volatile composition nor the quantity of components or the Nocturnal Emission patterns was altered. The mRNA and protein levels of the benzoic/salicylic acid carboxyl-methyltransferase, as well as its enzyme activity, also did not show any significant differences. These results indicate that metabolism in flowers at and postanthesis is an autonomous process and is independent of metabolic changes in green leaves. By this sustaining mechanism, N. suaveolens plants ensure sexual reproduction even under unfavorable conditions.
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Regulation of simultaneous synthesis of floral scent terpenoids by the 1,8-cineole synthase of Nicotiana suaveolens
Plant Molecular Biology, 2007Co-Authors: Susanna Roeder, Uta Effmert, Anna-maria Hartmann, Birgit PiechullaAbstract:The white flowers of N. suaveolens emit a complex bouquet of fragrance volatiles. The dominant compounds are benzenoids (e.g. methyl benzoate, methyl salicylate, benzyl benzoate and benzyl salicylate), monoterpenes (1,8-cineole, limonene, sabinene, E -β-ocimene, β-β-myrcene, α- and β-pinene and α-terpineole) and sesquiterpenes (e.g. caryophyllene), which are all emitted at higher levels during the night. Here, we show that the simultaneous Nocturnal Emission of most monoterpenes is realized by a single floral-specific multi-product enzyme (1,8-cineole synthase, CIN), which synthesizes the monoterpenes of the “cineole cassette”. Interestingly, N. suaveolens is the only known taxon of the Suaveolentes section to have a flower emitting “cineole cassette of monoterpenes” which is otherwise typical for the Alatae section. Gene sequence analysis of CIN has revealed the highest similarities to other angiosperm monoterpene synthases from Vitis vinifera , Quercus ilex , Citrus unshiu and C. limon , which cluster in the same branch of the terpene synthase B subfamily. However, based on its synthesized products, N. suaveolens CIN shares similarity with enzymes of the Arabidopsis thaliana root and Salvia officinalis leaf. The N. suaveolens CIN gene is only expressed in the stigma/style tissue and petals. Thin sections of petals present the enzyme primarily in the adaxial and abaxial epidermis; this facilitates the comprehensive Emission of volatiles in all spacial directions. The oscillation of monoterpene Emission is a consequence of the regulation of the CIN gene by the circadian clock, with oscillations occurring at the level of transcript and protein accumulations and of enzyme activity. Light/dark or dark/light transition signals synchronize the slow-running endogenous clock. Two strategies for synchronized scent Emission have been established in N. suaveolens flowers: (i) the synthesis of volatile organic compounds by a multi-product enzyme and (ii) the coordination of biosynthetic pathways by a circadian clock.
Linn Berger Håkonsen - One of the best experts on this subject based on the ideXlab platform.
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In utero exposure to alcohol and puberty in boys: a pregnancy cohort study
BMJ open, 2014Co-Authors: Linn Berger Håkonsen, Jørn Olsen, Ane Marie Thulstrup, Mette Louise Brath-lund, Marie Louise Hounsgaard, Andreas Ernst, Bodil Hammer Bech, Cecilia Høst Ramlau-hansenAbstract:Objectives: Epidemiological studies have raised concerns about the reproductive consequences of in utero exposure to alcohol. Maternal lifestyle factors have been associated with altered pubertal development, but the impact of prenatal alcohol exposure on male puberty is unknown. Thus, the objective was to explore whether prenatal alcohol exposure alters pubertal development in boys. Setting: Follow-up of a Danish pregnancy cohort. Participants: Sons (N=2522) of women who were enrolled in a Danish pregnancy cohort between 1984 and 1987. Primary and secondary outcome measures: Indicators of pubertal development, assessed by age at first Nocturnal Emission, voice break, acne and regular shaving. Results: We found a tendency towards a later age at first Nocturnal Emission and voice break following in utero exposure to binge drinking. Boys exposed to ≥5 binge drinking episodes during pregnancy experienced their first Nocturnal Emission 7.3 months (95% CI −2.8 to 17.4) later and voice break 4.9 months (95% CI −0.6 to 10.4) later than the unexposed boys. Results for average weekly alcohol consumption were in the same direction, but differences were smaller and not statistically significant. Conclusions: We found no strong support for the hypothesis that in utero exposure to weekly alcohol consumption is a risk factor for altered pubertal development, but a tendency towards delayed pubertal development among boys exposed to binge drinking during fetal life was observed. Longitudinal studies, with data collected as children go through puberty, are needed to explore this further.
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Maternal pre-pregnancy body mass index and pubertal development among sons
Andrology, 2013Co-Authors: M L Hounsgaard, Linn Berger Håkonsen, Ane Marie Thulstrup, Anne Vested, Jens Peter Bonde, Ellen A. Nohr, Cecilia Høst Ramlau-hansenAbstract:Summary Maternal overweight and obesity in pregnancy has been associated with earlier age of menarche in daughters as well as reduced semen quality in sons. We aimed at investigating pubertal development in sons born by mothers with a high body mass index (BMI). The study included 2522 sons of mothers that during pregnancy in 1984–1987 were enrolled in a mother–child cohort and gave information on their pre-pregnancy height and weight from which we calculated their BMI. Information on sons' pubertal development, assessed by age when starting regular shaving, voice break, acne and first Nocturnal Emission, was obtained from web-based questionnaires in 2005, when sons were 18–21 years old. Multiple linear regression analyses showed that sons of obese mothers on average started to shave regularly 8.3 (95% confidence interval: 2.5–14.0) months earlier than sons of normal weight mothers. For the three other indicators of pubertal development, results also indicated earlier pubertal development among sons of obese mothers. After excluding sons of underweight mothers in a subanalysis, we observed an inverse trend between maternal pre-pregnancy BMI and age at regular shaving, acne and first Nocturnal Emission. In conclusion, maternal pre-pregnant obesity may be related to earlier timing of pubertal milestones among sons. More research, preferably based on prospectively collected information about pubertal development, is needed to draw firm conclusions.
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Maternal cigarette smoking during pregnancy and pubertal development in sons. A follow-up study of a birth cohort
Andrology, 2013Co-Authors: Linn Berger Håkonsen, Jørn Olsen, Henrik Støvring, Anja Ernst, Ane Marie Thulstrup, Jin Liang Zhu, Anshu Shrestha, Cecilia Høst Ramlau-hansenAbstract:Summary Epidemiological studies have raised concern about the reproductive consequences of prenatal cigarette smoking exposure, possibly affecting semen quality and onset of pubertal development of the offspring. The aim of this study was to further investigate pubertal development in young men exposed to cigarette smoking in foetal life. In a Danish pregnancy cohort, information on maternal smoking during pregnancy was available from questionnaires administered in 1984–1987, and information on pubertal development, assessed by age at first Nocturnal Emission, acne, voice break and regular shaving, was obtained from a follow-up questionnaire administered in 2005 to the young men (age: 18–21). We found no significant association between prenatal cigarette smoking exposure and earlier onset of puberty, but we did observe a tendency towards earlier age of first Nocturnal Emission, acne and voice break, indicating an accelerated age of pubertal development. Men exposed to ≥15 cigarettes/day had 3.1 months (95% CI: −6.4; 0.2) earlier age at acne and 2.2 months (95% CI: −7.3; 3.0) earlier age at first Nocturnal Emission, 1.2 months (95% CI: −4.6; 2.2) earlier age at voice break, however, 1.3 months (95% CI: −1.6; 4.3) later age at regular shaving, compared with unexposed men. Prenatal cigarette smoking exposure may induce an earlier age at onset of puberty in young men, but larger studies with prospectively collected data on pubertal development are needed to explore this hypothesis further.
Om P. Singh - One of the best experts on this subject based on the ideXlab platform.
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The Frequency of Sexual Dysfunctions in Patients Attending a Sex Therapy Clinic in North India
Archives of Sexual Behavior, 1998Co-Authors: Kaushal K. Verma, Binod K. Khaitan, Om P. SinghAbstract:Analyzed data on 1000 consecutive patients with sexual disorders attending the psychosexual clinic at the All India Institute of Medical Sciences. The majority of patients were educated males between 21 and 30 years of age, belonging to the middle class. There was a slight preponderance of married patients. Fifty-two percent of patients had premarital or extramarital sexual contact; less than 5% had had homosexual contact; 10% had no sexual contact. Most patients had more than one complaint. Premature ejaculation (77.6%) and Nocturnal Emission (71.3%) were the most frequent problems followed by a feeling of guilt about masturbation (33.4%) and small size of the penis (30%). Erectile dysfunction was a complaint of 23.6%. Excessive worry about Nocturnal Emission, abnormal sensations in the genitals, and venereophobia was reported in 19.5, 13.6, and 13% of patients, respectively. Only 36 female patients attended the clinic with their spouses.
Ane Marie Thulstrup - One of the best experts on this subject based on the ideXlab platform.
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In utero exposure to alcohol and puberty in boys: a pregnancy cohort study
BMJ open, 2014Co-Authors: Linn Berger Håkonsen, Jørn Olsen, Ane Marie Thulstrup, Mette Louise Brath-lund, Marie Louise Hounsgaard, Andreas Ernst, Bodil Hammer Bech, Cecilia Høst Ramlau-hansenAbstract:Objectives: Epidemiological studies have raised concerns about the reproductive consequences of in utero exposure to alcohol. Maternal lifestyle factors have been associated with altered pubertal development, but the impact of prenatal alcohol exposure on male puberty is unknown. Thus, the objective was to explore whether prenatal alcohol exposure alters pubertal development in boys. Setting: Follow-up of a Danish pregnancy cohort. Participants: Sons (N=2522) of women who were enrolled in a Danish pregnancy cohort between 1984 and 1987. Primary and secondary outcome measures: Indicators of pubertal development, assessed by age at first Nocturnal Emission, voice break, acne and regular shaving. Results: We found a tendency towards a later age at first Nocturnal Emission and voice break following in utero exposure to binge drinking. Boys exposed to ≥5 binge drinking episodes during pregnancy experienced their first Nocturnal Emission 7.3 months (95% CI −2.8 to 17.4) later and voice break 4.9 months (95% CI −0.6 to 10.4) later than the unexposed boys. Results for average weekly alcohol consumption were in the same direction, but differences were smaller and not statistically significant. Conclusions: We found no strong support for the hypothesis that in utero exposure to weekly alcohol consumption is a risk factor for altered pubertal development, but a tendency towards delayed pubertal development among boys exposed to binge drinking during fetal life was observed. Longitudinal studies, with data collected as children go through puberty, are needed to explore this further.
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Maternal pre-pregnancy body mass index and pubertal development among sons
Andrology, 2013Co-Authors: M L Hounsgaard, Linn Berger Håkonsen, Ane Marie Thulstrup, Anne Vested, Jens Peter Bonde, Ellen A. Nohr, Cecilia Høst Ramlau-hansenAbstract:Summary Maternal overweight and obesity in pregnancy has been associated with earlier age of menarche in daughters as well as reduced semen quality in sons. We aimed at investigating pubertal development in sons born by mothers with a high body mass index (BMI). The study included 2522 sons of mothers that during pregnancy in 1984–1987 were enrolled in a mother–child cohort and gave information on their pre-pregnancy height and weight from which we calculated their BMI. Information on sons' pubertal development, assessed by age when starting regular shaving, voice break, acne and first Nocturnal Emission, was obtained from web-based questionnaires in 2005, when sons were 18–21 years old. Multiple linear regression analyses showed that sons of obese mothers on average started to shave regularly 8.3 (95% confidence interval: 2.5–14.0) months earlier than sons of normal weight mothers. For the three other indicators of pubertal development, results also indicated earlier pubertal development among sons of obese mothers. After excluding sons of underweight mothers in a subanalysis, we observed an inverse trend between maternal pre-pregnancy BMI and age at regular shaving, acne and first Nocturnal Emission. In conclusion, maternal pre-pregnant obesity may be related to earlier timing of pubertal milestones among sons. More research, preferably based on prospectively collected information about pubertal development, is needed to draw firm conclusions.
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Maternal cigarette smoking during pregnancy and pubertal development in sons. A follow-up study of a birth cohort
Andrology, 2013Co-Authors: Linn Berger Håkonsen, Jørn Olsen, Henrik Støvring, Anja Ernst, Ane Marie Thulstrup, Jin Liang Zhu, Anshu Shrestha, Cecilia Høst Ramlau-hansenAbstract:Summary Epidemiological studies have raised concern about the reproductive consequences of prenatal cigarette smoking exposure, possibly affecting semen quality and onset of pubertal development of the offspring. The aim of this study was to further investigate pubertal development in young men exposed to cigarette smoking in foetal life. In a Danish pregnancy cohort, information on maternal smoking during pregnancy was available from questionnaires administered in 1984–1987, and information on pubertal development, assessed by age at first Nocturnal Emission, acne, voice break and regular shaving, was obtained from a follow-up questionnaire administered in 2005 to the young men (age: 18–21). We found no significant association between prenatal cigarette smoking exposure and earlier onset of puberty, but we did observe a tendency towards earlier age of first Nocturnal Emission, acne and voice break, indicating an accelerated age of pubertal development. Men exposed to ≥15 cigarettes/day had 3.1 months (95% CI: −6.4; 0.2) earlier age at acne and 2.2 months (95% CI: −7.3; 3.0) earlier age at first Nocturnal Emission, 1.2 months (95% CI: −4.6; 2.2) earlier age at voice break, however, 1.3 months (95% CI: −1.6; 4.3) later age at regular shaving, compared with unexposed men. Prenatal cigarette smoking exposure may induce an earlier age at onset of puberty in young men, but larger studies with prospectively collected data on pubertal development are needed to explore this hypothesis further.