Clinical Relevance of Adolescent OCP Use and Depression Risk

Prevalence of depression within the United States has risen significantly in recent years.1 Depression in females has increased by 12 percent compared to 3.8 percent in males between 2009 and 2019.3 Hormonal contraceptives are widely used by women throughout the world and often started as early as menarche. Traditionally intended to prevent unwanted pregnancies, contraceptives are frequently used in the symptom management of menorrhagia and dysmenorrhea in females.2 Oral contraceptive pills (OCP) are a popular choice for adolescents due to their ease of use, formulation varieties, and ability to be used long-term. Considering the widespread use, the adverse effects can have significant clinical relevance.3 OCPs have a wide variety of side effects - including mood changes; however, there is no clear consensus among researchers and clinicians on the associations between OCP use and risk of depression.2 Nevertheless, mood changes are a common reason for discontinuation of OCPs. Further investigation into the possible connection between hormonal contraceptive use and depression may offer insight into the prevalence of depression in adolescent females compared to adolescent males and should be taken into consideration by clinicians. Overall, medical providers should be better equipped to address these concerns with their patients. The purpose of this study is to conduct a literature review based on global studies investigating possible correlation between the use of hormonal contraceptives in adolescent females and subsequent mood changes, such as depression

Current and Historical Drivers of Landscape Genetic Structure Differ in Core and Peripheral Salamander Populations

With predicted decreases in genetic diversity and greater genetic differentiation at range peripheries relative to their cores, it can be difficult to distinguish between the roles of current disturbance versus historic processes in shaping contemporary genetic patterns. To address this problem, we test for differences in historic demography and landscape genetic structure of coastal giant salamanders (Dicamptodon tenebrosus) in two core regions (Washington State, United States) versus the species' northern peripheral region (British Columbia, Canada) where the species is listed as threatened. Coalescent-based demographic simulations were consistent with a pattern of post-glacial range expansion, with both ancestral and current estimates of effective population size being much larger within the core region relative to the periphery. However, contrary to predictions of recent human-induced population decline in the less genetically diverse peripheral region, there was no genetic signature of population size change. Effects of current demographic processes on genetic structure were evident using a resistance-based landscape genetics approach. Among core populations, genetic structure was best explained by length of the growing season and isolation by resistance (i.e. a ‘flat’ landscape), but at the periphery, topography (slope and elevation) had the greatest influence on genetic structure. Although reduced genetic variation at the range periphery of D. tenebrosus appears to be largely the result of biogeographical history rather than recent impacts, our analyses suggest that inherent landscape features act to alter dispersal pathways uniquely in different parts of the species' geographic range, with implications for habitat management

TRY plant trait database – enhanced coverage and open access

Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Comparative effects of glucose and xylose on blood pressure, gastric emptying and incretin hormones in healthy older subjects

Postprandial hypotension is an important disorder for which current management is suboptimal. In healthy older subjects, oral and small-intestinal glucose administration decreases blood pressure (BP), and the magnitude of the reduction is dependent on the rate of glucose entry into the small intestine and, possibly, the release of glucagon-like peptide-1 (GLP-1). There is little information about the effects of other carbohydrates, particularly those poorly absorbed, on BP. The aim of the present study was to compare the effects of drinks containing xylose, glucose or water alone on BP, gastric emptying (GE), incretin hormone secretion, glycaemia and insulinaemia in healthy older subjects. A total of eight healthy older subjects (aged 65–75 years) had simultaneous measurements of BP (DINAMAP), GE (three-dimensional ultrasound), blood glucose, serum insulin, GLP-1 and glucose-dependent insulinotropic peptide (GIP), on three separate occasions, in a double-blind, randomised order. On each day, subjects consumed a 300 ml drink of water, glucose (50 g) or d-xylose (50 g). Glucose (P = 0·02), but not xylose (P = 0·63), was associated with a fall in BP. There was no difference in the GE of glucose and xylose (P = 0·47); both emptied slower than water (P < 0·001). Xylose had minimal effects on blood glucose, serum insulin or serum GIP, but was more potent than glucose in stimulating GLP-1 (P = 0·002). In conclusion, in healthy older subjects, xylose empties from the stomach at the same rate as glucose, but has no effect on BP, possibly because it is a potent stimulus for GLP-1 release. Xylose may be considered as an alternative sweetener to glucose in the management of postprandial hypotension.Lora Vanis, Trygve Hausken, Diana Gentilcore, Rachael S. Rigda, Christopher K. Rayner, Christine Feinle-Bisset, Michael Horowitz and Karen L. Jone

TRY plant trait database - enhanced coverage and open access

10.1111/gcb.14904GLOBAL CHANGE BIOLOGY261119-18