exogenous hormones
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2021 ◽  
Vol 12 ◽  
Author(s):  
Fenqi Chen ◽  
Xiangzhuo Ji ◽  
Mingxing Bai ◽  
Zelong Zhuang ◽  
Yunling Peng

The planting method of deep sowing can make the seeds make full use of water in deep soil, which is considered to be an effective way to respond to drought stress. However, deep sowing will affect the growth and development of maize (Zea mays L.) at seedling stage. To better understand the response of maize to deep sowing stress and the mechanism of exogenous hormones [Gibberellin (GA3), Brassinolide (BR), Strigolactone (SL)] alleviates the damaging effects of deep-sowing stress, the physiological and transcriptome expression profiles of seedlings of deep sowing sensitive inbred line Zi330 and the deep-tolerant inbred line Qi319 were compared under deep sowing stress and the conditions of exogenous hormones alleviates stress. The results showed that mesocotyl elongated significantly after both deep sowing stress and application of exogenous hormones, and its elongation was mainly through elongation and expansion of cell volume. Hormone assays revealed no significant changes in zeatin (ZT) content of the mesocotyl after deep sowing and exogenous hormone application. The endogenous GA3 and auxin (IAA) contents in the mesocotyl of the two inbred lines increased significantly after the addition of exogenous GA3, BR, and SL under deep sowing stress compared to deep sowing stress, while BR and SL decreased significantly. Transcriptome analysis showed that the deep seeding stress was alleviated by GA3, BR, and SLs, the differentially expressed genes (DEGs) mainly included cellulose synthase, expansin and glucanase, oxidase, lignin biosynthesis genes and so on. We also found that protein phosphatase 2C and GA receptor GID1 enhanced the ability of resist deep seeding stress in maize by participating in the abscisic acid (ABA) and the GA signaling pathway, respectively. In addition, we identified two gene modules that were significantly related to mesocotyl elongation, and identified some hub genes that were significantly related to mesocotyl elongation by WGCNA analysis. These genes were mainly involved in transcription regulation, hydrolase activity, protein binding and plasma membrane. Our results from this study may provide theoretical basis for determining the maize deep seeding tolerance and the mechanism by which exogenous hormones regulates deep seeding tolerance.


BMC Medicine ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Mathilde His ◽  
Vivian Viallon ◽  
Laure Dossus ◽  
Julie A. Schmidt ◽  
Ruth C. Travis ◽  
...  

Abstract Background Metabolomics is a promising molecular tool for identifying novel etiological pathways leading to cancer. In an earlier prospective study among pre- and postmenopausal women not using exogenous hormones, we observed a higher risk of breast cancer associated with higher blood concentrations of one metabolite (acetylcarnitine) and a lower risk associated with higher blood concentrations of seven others (arginine, asparagine, phosphatidylcholines (PCs) aa C36:3, ae C34:2, ae C36:2, ae C36:3, and ae C38:2). Methods To identify determinants of these breast cancer-related metabolites, we conducted a cross-sectional analysis to identify their lifestyle and anthropometric correlates in 2358 women, who were previously included as controls in case-control studies nested within the European Prospective Investigation into Cancer and Nutrition cohort and not using exogenous hormones at blood collection. Associations of each metabolite concentration with 42 variables were assessed using linear regression models in a discovery set of 1572 participants. Significant associations were evaluated in a validation set (n = 786). Results For the metabolites previously associated with a lower risk of breast cancer, concentrations of PCs ae C34:2, C36:2, C36:3, and C38:2 were negatively associated with adiposity and positively associated with total and saturated fat intakes. PC ae C36:2 was also negatively associated with alcohol consumption and positively associated with two scores reflecting adherence to a healthy lifestyle. Asparagine concentration was negatively associated with adiposity. Arginine and PC aa C36:3 concentrations were not associated to any of the factors examined. For the metabolite previously associated with a higher risk of breast cancer, acetylcarnitine, a positive association with age was observed. Conclusions These associations may indicate possible mechanisms underlying associations between lifestyle and anthropometric factors, and risk of breast cancer. Further research is needed to identify potential non-lifestyle correlates of the metabolites investigated.


BMJ Open ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. e046400
Author(s):  
Won Jai Jung ◽  
Sang Yeub Lee ◽  
Sue In Choi ◽  
Byung-Keun Kim ◽  
Eun Joo Lee ◽  
...  

ObjectivesSeveral studies have suggested the influence of exogenous hormones on asthma, but the results are still conflicting. Moreover, there has been little associated research on Asian population. This study aimed to assess the association between use of exogenous female sex hormones and asthma in Korean women.DesignKorea National Health and Nutrition Examination Survey (KNHANES) is a nationwide programme to assess national health and nutritional status in Korea. A population-based study was conducted to analyse the relationship between self-reported asthma and exogenous hormones using the KNHANES between 2007 and 2012.ParticipantsThe study sample included 6874 premenopausal and 4912 postmenopausal women aged 30–65.Outcome measuresKNHANES data comprised health interviews and physical examinations. Questionnaires regarding asthma, reproductive factors and exogenous hormones were included.ResultsAmong postmenopausal women, 3.4% reported doctor-diagnosed asthma. Hormone replacement therapy (HRT) was associated with increased odds of doctor-diagnosed asthma (OR 1.56; 95% CI 1.04 to 2.35), while the association between HRT and wheeze in the last 1 year was not significant (OR 1.37; 95% CI 0.95 to 1.96). In premenopausal women, the prevalence of asthma was 2.3%. Use of oral contraceptives (OCs) was associated with an increased odds of doctor-diagnosed asthma (OR 1.67; 95% CI 1.01 to 2.76) and wheeze in the last 1 year (OR 1.88; 95% CI 1.31 to 2.69). These associations were dominant among non-obese women (body mass index <25 kg/m2; OR 2.36; 95% CI 1.34 to 4.17 for asthma and OR 2.15; 95% CI 1.43 to 3.23 for wheeze).ConclusionsHRT and OCs were associated with increased asthma in postmenopausal and premenopausal women, respectively. The association between OC use and asthma was strong in non-obese premenopausal women.


Author(s):  
Demissie Tilaye ◽  
Yilma Tefera ◽  
Degefa Tamrat ◽  
Wirtu Gemechu ◽  
Lemma Alemayehu

Genetic differences have been suggested as a possible cause for variation in responses to exogenous hormones. Here we evaluated the effect of follicle ablation, exogenous FSH and coasting time prior to ovum pick-up (OPU) on the number of follicles suitable for aspiration, oocyte quality, and cleavage rate in Ethiopian Boran cows. The experiment was carried out in three parts, I) Cows were synchronized using 500µg PGF2α given 11 days apart. Cows were then subjected to a biweekly ovum pickup session before ovulation (n=5) or starting Day 7 after ovulation (n=4) for three weeks. II) Cows were similarly synchronized and all visible follicles were ablated on the first days of overt estrus which were then further grouped into cows that received a divided dose of 350IU FSH (n=5) or 175IU FSH (n=5) over three days. In both groups OPU was carried out weekly starting 48h after the last FSH for six weeks. III) A similar protocol as in part II was carried out but coasting period was increased to 72hrs for cows that received 350IU FSH as divided dose (n=5) and 48hrs coasting period for single 350IU FSH dose (n=5). The covariates of follicles and oocyte were not affected (P>0.05) by corpus luteum presence at OPU. The mean number of medium (7.36±0.57) and large (8.28±0.96) follicles were significantly higher (P<0.05) in group that received divided 350IU FSH. Similarly, the mean number of Grade-1 (4.19±0.24) and Grade-2 (4.32±.27) COC, maturation rate (70.41%) and cleavage rate (47.5%) were significantly higher (P<0.05) in group that received 350IU FSH. COC quality was significantly (P<0.05) influenced by costing period. However, both maturation and cleavage rates were not affected by the coasting period. This study demonstrated that follicular ablation and treatment with FSH improves follicular population and oocyte recovery rate in Boran cows.


Author(s):  
J. González-Maldonado ◽  
P. Pérez Hernández ◽  
J. Salazar Ortiz ◽  
C. Cortez Romero ◽  
J. Gallegos-Sánchez ◽  
...  

Objective: To review the metabolic and hormonal processes that regulate reproductive activity in dairy cattleduring the postpartum anestrus period.Design/methodology/approach: Analysis of scientific documents and systematization of information relatedto the reproductive physiology and management of dairy cattle in postpartum anestrus.Results: Postpartum anestrus is an event that occurs naturally and is necessary for restoration of the homeostasisof the cow’s body following calving. However, failure to reestablish this homeostasis actually increases itsduration and negatively affects the subsequent reproductive performance of the individual cow.Limitations on study/implications: Reproductive management decisions must be based on scientificknowledge.Findings/conclusions: Management of dairy cattle in the postpartum anestrus period should focus onreestablishment of the state of homeostasis and the subsequent reproductive activity, with nutritional andhormonal strategies implemented to induce cyclicity, ovulation and formation of the first corpus luteum in thatperiod, through application of exogenous hormones after day ten postpartum.


2021 ◽  
Vol 50 (Supplement_1) ◽  
Author(s):  
Therese Johansson ◽  
Docent Åsa Johansson ◽  
Torgny Karlsson ◽  
Docent Weronica E Ek ◽  
Philip Fowler

Abstract Background Millions of women use exogenous hormones as hormone replacement therapy (HRT) or oral contraceptives (OC). Still, time-dependent and long-term consequences of exogenous hormones on cerebrovascular health remains unclear. Methods We examined the effects of HRT and OC usage on stroke risk in 256,661 women from UK Biobank, born between 1939 and 1970. Outcomes included any type of stroke, ischemic stroke (IS), intracerebral hemorrhage (IH), and subarachnoid hemorrhage (SH). Exposures were analyzed as time-dependent variables in Cox regression models. Results are expressed as hazard ratios (HR) with 95% confidence intervals. Results During first year of exposure, HRT usage was associated with higher hazard rates of any stroke (HR = 2.12[1.66-2.70]), IS (HR = 1.93[1.04-3.56]) and SH (HR = 2.14[1.23-3.72]) compared to non-usage, which remained significant only for any stroke during remaining years of exposure. Similarly, we observed an increased hazard of any stroke during first year of OC exposure (HR = 2.29[1.34-3.92]), while the hazards were found to be comparable during remaining years of use (HR = 1.03[0.92-1.17]). Conversely, women who previously had been exposed to OC, had a lower hazard rate of any stroke later in life, (HR = 0.88[0.82-0.94]). Conclusions Our findings suggest that HRT and OC use cause immediate changes in hemostatic balance, therefore increasing the short-term stroke risk. However, long-term effects of OC use during reproductive years might improve cerebrovascular health and prevent stroke events later in life. Key messages HRT usage increase the risk of stroke, both short-term and with longer use, while the increased stroke risk might be limited to the first year of OC use.


Author(s):  
Rhea Harewood ◽  
Ruth Disney ◽  
James Kinross ◽  
Christian von Wagner ◽  
Amanda J. Cross

Abstract Purpose Evidence of differences in the etiology of, and poorer survival from, proximal colon compared to the distal colorectum, necessitates research into its risk factors. This systematic review summarizes the evidence on medication use and proximal colon cancer risk. Methods MEDLINE and EMBASE were searched for prospective studies investigating nine medication groups, namely non-steroidal anti-inflammatory drugs (NSAIDs), exogenous hormones, i.e., hormone replacement therapy (HRT) or oral contraceptives (OCs), statins, proton pump inhibitors, anti-hypertensives, metformin (an antidiabetic), antidiarrheals or laxatives, and the risk of proximal colon cancer. Narrative synthesis and meta-analyses, using random effects models to estimate risk ratios (RRs) and 95% confidence intervals (CIs), were conducted. Results Twenty nine publications investigating NSAIDs (n = 13), exogenous hormones [HRT (n = 9) or OCs (n = 4)] statins (n = 5), anti-hypertensives (n = 1), and metformin (n = 1) were included. Summary RRs reported a protective effect of aspirin use (RR 0.80, 95% CI 0.73–0.89) but no associations between HRT (RR 0.92, 95% CI 0.83–1.02), OC (RR 1.06, 95% CI 0.98–1.14) or statin use (RR 0.94, 95% CI 0.67–1.31), and proximal colon cancer incidence compared to never/non-use. One study on metformin and one on anti-hypertensives reported no association. Sources of between-study heterogeneity included study design, period of exposure ascertainment, exposure source, and exposure comparison, but this exploration was hindered by the small numbers of studies. Conclusion Despite some studies on NSAID or HRT use, evidence on the impact of a range of medications on proximal colon cancer risk is limited. This highlights the need for more research to inform chemoprevention strategies.


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