scholarly journals The dog as a sentinel species for environmental effects on human fertility

Reproduction ◽  
2020 ◽  
Vol 159 (6) ◽  
pp. R265-R276 ◽  
Author(s):  
Rebecca Nicole Sumner ◽  
Imogen Thea Harris ◽  
Morne Van der Mescht ◽  
Andrew Byers ◽  
Gary Crane William England ◽  
...  
Keyword(s):  
Current Knowledge ◽  
Sperm Quality ◽  
Analytical Data ◽  
Real Life ◽  
Biological Tissues ◽  
Environmental Chemicals ◽  
Human Reproduction ◽  
Sentinel Species ◽  
Environmental Toxicants ◽  
Long Term Effects

Despite the vast body of evidence that environmental toxicants adversely affect reproductive development and function across species, demonstrating true cause and effect in the human remains a challenge. Human meta-analytical data, showing a temporal decline in male sperm quality, are paralleled by a single laboratory study showing a similar 26-year decline in the dog, which shares the same environment. These data are indicative of a common cause. Environmental chemicals (ECs) detected in reproductive tissues and fluids induce similar, short term, adverse effects on human and dog sperm. Both pre- and post-natal stages of early life development are sensitive to chemical exposures and such changes could potentially cause long term effects in the adult. The environmental ‘pollutome’ (mixtures of ECs) is determined by industrialisation, atmospheric deposition and bioaccumulation and characterises real-life exposure. In Arctic ecosystems, dietary and non-dietary chemical contaminants are detectable in biological tissues and linked with adverse health effects in both dogs and their handlers. In the female, such exposure could contribute to disorders such as ovarian insufficiency, dysregulated follicle development, ovarian cancer, and polycystic ovarian syndrome. In the dog, ovarian chemical concentrations are greater in the testis. In addition, preliminary studies indicate that dietary exposures may influence the sex ratio in the offspring in favour of females. Within this article, we review current knowledge on chemical effects on human reproduction and suggest that the dog, as a sentinel species for such effects, is an essential tool for addressing critical data gaps in this field.

Making the most of sperm activation responses: experiments with boar spermatozoa and bicarbonate

2018 ◽  
Vol 30 (6) ◽  
pp. 842 ◽  
Author(s):  
William V. Holt ◽  
Nana Satake
Keyword(s):  
Semen Quality ◽  
Current Knowledge ◽  
Sperm Quality ◽  
Environmental Chemicals ◽  
Information Value ◽  
In Vitro Tests ◽  
Sperm Activation ◽  
Activation Mechanisms

Attempting to extract useful and reliable information about semen quality and its fertility potential remains a difficult exercise, partly because the sperm heterogeneity within samples often renders simple statistical analyses rather meaningless. In fact, a mean and standard deviation may reflect neither the very fast swimming activities of the most active cells nor the slow and sluggish activities of others. Herein we propose that the information value within semen samples can be maximised if current knowledge about sperm activation mechanisms is exploited before undertaking the measurements. We explain, using boar semen as an example, that estimating and defining relative sperm subpopulation sizes, after activation by bicarbonate, provides a means of quantifying sperm quality. Although such estimates may indeed be related to in vivo fertility, the general approach also suggests potential new avenues that could be exploited for the elaboration of novel in vitro tests for the characterisation of toxic environmental chemicals and, indeed, to reduce the number of animals used in such testing programs.

scholarly journals Embryo biopsy and development: the known and the unknown

Reproduction ◽  
2017 ◽  
Vol 154 (5) ◽  
pp. R143-R148 ◽  
Author(s):  
Federica Zacchini ◽  
Roberta Arena ◽  
Adam Abramik ◽  
Grazyna E Ptak
Keyword(s):  
Clinical Practice ◽  
Preimplantation Genetic Diagnosis ◽  
Current Knowledge ◽  
Genetic Diagnosis ◽  
In Utero ◽  
Human Reproduction ◽  
Embryo Biopsy ◽  
Postnatal Life ◽  
Long Term Effects ◽  
Blastomere Biopsy

Preimplantation genetic diagnosis (PGD) has been introduced in clinical practice as a tool for selecting ‘healthy’ embryos before their transfer in utero. PGD protocols include biopsy of cleaving embryos (blastomere biopsy (BB)) or blastocysts (trophectoderm biopsy (TB)), followed by genetic analysis to select ‘healthy’ embryos for transfer in utero. Currently, TB is replacing the use of BB in the clinical practice. However, based on the European Society of Human Reproduction and Embryology Preimplantation Genetic Diagnosis Consortium reports, BB has been used in >87% of PGD cycles for more than 10 years. An exhaustive evaluation of embryo biopsy (both BB and TB) risks and safety is still missing. The few epidemiological studies available are quite controversial and/or are limited to normalcy at birth or early childhood. On the other hand, studies on animals have shown that BB can be a risk factor for impaired development, during both pre- and postnatal life, while little is known on TB. Thus, there is an urgent need of focused researches on BB, as it has contributed to give birth to children for more than 10 years, and on TB, as its application is significantly growing in clinical practice. In this context, the aim of this review is to provide a complete overview of the current knowledge on the short-, medium- and long-term effects of embryo biopsy in the mouse model.

scholarly journals Environmental exposures, fetal testis development and function: phthalates and beyond

Reproduction ◽  
2021 ◽  
Author(s):  
Hui Li ◽  
Daniel J. Spade
Keyword(s):  
Germ Cell ◽  
Germ Cells ◽  
Molecular Mechanisms ◽  
Cell Function ◽  
Current Knowledge ◽  
Environmental Chemicals ◽  
Environmental Toxicants ◽  
Cell Contacts ◽  
Testis Development ◽  
Fetal Testis

Fetal development of the mammalian testis relies on a series of interrelated cellular processes: commitment of somatic progenitor cells to Sertoli and Leydig cell fate, migration of endothelial cells and Sertoli cells, differentiation of germ cells, deposition of basement membrane, and establishment of cell-cell contacts, including Sertoli-Sertoli and Sertoli-germ cell contacts. These processes are orchestrated by intracellular, endocrine, and paracrine signaling processes. Because of this complexity, testis development can be disrupted by a variety of environmental toxicants. Toxicity of phthalic acid esters (phthalates) to the fetal testis has been the subject of extensive research for two decades, and phthalates have become an archetypal fetal testis toxicant. Phthalates disrupt the seminiferous cord formation and maturation, Sertoli cell function, biosynthesis of testosterone in Leydig cells, and impair germ cell survival and development, producing characteristic multinucleated germ cells. However, the mechanisms responsible for these effects are not fully understood. This review describes current knowledge of the adverse effects of phthalates on the fetal testis and their associated windows of sensitivity, and compares and contrasts the mechanisms by which toxicants of current interest, bisphenol A and its replacements, analgesics, and perfluorinated alkyl substances, alter testicular developmental processes. Working towards a better understanding of the molecular mechanisms responsible for phthalate toxicity will be critical for understanding the long-term impacts of environmental chemicals and pharmaceuticals on human reproductive health.

scholarly journals Predictors and Early Markers of Response to Biological Therapies in Inflammatory Bowel Diseases

2021 ◽  
Vol 10 (4) ◽  
pp. 853
Author(s):  
Giuseppe Privitera ◽  
Daniela Pugliese ◽  
Gian Ludovico Rapaccini ◽  
Antonio Gasbarrini ◽  
Alessandro Armuzzi ◽  
...  
Keyword(s):  
Inflammatory Bowel Diseases ◽  
Current Knowledge ◽  
Real Life ◽  
Response To Therapy ◽  
Significant Heterogeneity ◽  
Intestinal Damage ◽  
Biological Therapies ◽  
Early Markers ◽  
Bowel Diseases ◽  
Inflammatory Bowel

Inflammatory bowel diseases (IBD) are chronic conditions that primarily affect the gastrointestinal tract, with a complex pathogenesis; they are characterized by a significant heterogeneity of clinical presentations and of inflammatory pathways that sustain intestinal damage. After the introduction of the first biological therapies, the pipeline of therapies for IBD has been constantly expanding, and a significant number of new molecules is expected in the next few years. Evidence from clinical trials and real-life experiences has taught us that up to 40% of patients do not respond to a specific drug. Unfortunately, to date, clinicians lack a valid tool that can predict each patient’s response to therapies and that could help them in choosing what drug to administer. Several candidate biomarkers have been investigated so far, with conflicting results: clinical, genetic, immunological, pharmacokinetic and microbial markers have been tested, but no ideal marker has been identified so far. Based on recent evidence, multiparametric models seemingly hold the greatest potential for predicting response to therapy. In this narrative review, we aim to summarize the current knowledge on predictors and early markers of response to biological therapies in IBD.

Incest: What do we Really Know about It?

1987 ◽  
Vol 21 (4) ◽  
pp. 430-440 ◽  
Author(s):  
R. Kosky
Keyword(s):  
Adverse Effects ◽  
Sexual Activity ◽  
Sexual Intercourse ◽  
Current Knowledge ◽  
Epidemiological Studies ◽  
Scientific Basis ◽  
Long Term Effects ◽  
Clinical Series ◽  
General Populations

The literature on incest is reviewed. Current knowledge rests on a very insecure scientific basis and has been mainly derived from small, highly selected clinical series. Recently, some important epidemiological studies of general populations have been reported, but the results of prevalence are inconsistent. Overall, however, it appears that incest, when defined in terms of sexual intercourse, occurs in less than 1% of the population, but other forms of intrafamilial sexual activity may affect 10% of females before they are 16 years of age. Some children are more at risk than others. Because information has generally been derived from court or treatment samples, we are unclear about the long-term effects of incest experiences but, overall, the impression is that incest has markedly adverse effects, especially if it is accompanied by violence and threats and is directed, as it usually is, at the young pre-pubescent child.

scholarly journals Associations between Nature Exposure and Health: A Review of the Evidence

2021 ◽  
Vol 18 (9) ◽  
pp. 4790
Author(s):  
Marcia P. Jimenez ◽  
Nicole V. DeVille ◽  
Elise G. Elliott ◽  
Jessica E. Schiff ◽  
Grete E. Wilt ◽  
...  
Keyword(s):  
Mental Health ◽  
Physical Activity ◽  
Cognitive Function ◽  
Observational Studies ◽  
Green Space ◽  
Current Knowledge ◽  
Experimental Studies ◽  
Empirical Literature ◽  
Protective Effects ◽  
Long Term Effects

There is extensive empirical literature on the association between exposure to nature and health. In this narrative review, we discuss the strength of evidence from recent (i.e., the last decade) experimental and observational studies on nature exposure and health, highlighting research on children and youth where possible. We found evidence for associations between nature exposure and improved cognitive function, brain activity, blood pressure, mental health, physical activity, and sleep. Results from experimental studies provide evidence of protective effects of exposure to natural environments on mental health outcomes and cognitive function. Cross-sectional observational studies provide evidence of positive associations between nature exposure and increased levels of physical activity and decreased risk of cardiovascular disease, and longitudinal observational studies are beginning to assess long-term effects of nature exposure on depression, anxiety, cognitive function, and chronic disease. Limitations of current knowledge include inconsistent measures of exposure to nature, the impacts of the type and quality of green space, and health effects of duration and frequency of exposure. Future directions include incorporation of more rigorous study designs, investigation of the underlying mechanisms of the association between green space and health, advancement of exposure assessment, and evaluation of sensitive periods in the early life-course.

Seasonal reproduction and gonadal function: A focus on humans starting from animal studies

2021 ◽  
Author(s):  
Ester Beltran-Frutos ◽  
Livio Casarini ◽  
Daniele Santi ◽  
Giulia Brigante
Keyword(s):  
Animal Studies ◽  
Current Knowledge ◽  
Seasonal Pattern ◽  
Human Reproduction ◽  
Gonadal Function ◽  
Functional Changes ◽  
Morphological Variations ◽  
Gonadal Atrophy ◽  
Main Regulator ◽  
Seasonally Breeding

Abstract Photoperiod impacts reproduction in many species of mammals. Mating occurs at specific seasons to achieve reproductive advantages, such as optimization of offspring survival. Light is the main regulator of these changes during the photoperiod. Seasonally breeding mammals detect and transduce light signals through extraocular photoreceptor, regulating downstream melatonin-dependent peripheral circadian events. In rodents, hormonal reduction and gonadal atrophy occur quickly, and consensually with short-day periods. It remains unclear whether photoperiod influences human reproduction. Seasonal fluctuations of sex hormones have been described in humans, although they seem to not imply adaptative seasonal pattern in human gonads. This review discusses current knowledge about seasonal changes in the gonadal function of vertebrates, including humans. The photoperiod-dependent regulation of hypothalamic–pituitary-gonadal axis, as well as morphological and functional changes of the gonads are evaluated herein. Endocrine and morphological variations of reproductive functions, in response to photoperiod, are of interest as they may reflect the nature of past population selection for adaptative mechanisms that occurred during evolution.

Active Shooter Protocols: Perceptions, Preparedness, and Anxiety

2021 ◽  
Vol 26 (2) ◽  
pp. 91-100
Author(s):  
Veronica Worthington ◽  
Matthew Hayes ◽  
Melissa Reeves
Keyword(s):  
High School ◽  
Online Survey ◽  
Real Life ◽  
Unintended Consequences ◽  
Hierarchical Regression ◽  
Training Methods ◽  
Active Shooter ◽  
Long Term Effects ◽  
Perceived Knowledge

The national concern about active shootings has pushed schools to implement intense drills without considering unintended consequences. Studies have found that, although training had the potential to increase preparedness, it also increased anxiety. These findings apply to short-term effects, but there is a lack of empirical research on long-term effects of active shooter drills. The present study investigated whether active shooter training completed in high school impacts current levels of anxiety and preparedness of undergraduates. Collegiate participants (N = 364) completed an online survey and answered questions about their perceived knowledge of protocols, protocol actions, and training methods from high school followed by the same set of questions, this time referring to their current university. Participants then completed an anxiety measure (Spielberger, 1983) and a preparedness measure. Two hierarchical regression analyses were conducted to predict anxiety and preparedness. This study expanded findings on the effects of active shooter training by demonstrating long-term effects for high school training. Evacuation protocols (β = −.13, p = .03; β = .16, p = .007) and perceived knowledge (β = −.16, p = .004; β = .14, p = .01) positively impacted anxiety and preparedness, respectively, of university students. Experiences at the university level had an additional, larger impact on student anxiety, ΔR2 = .11, F(8, 347) = 5.88, p < .001, and preparedness, ΔR2> = .26, F(8, 347) = 17.32, p < .001, which seems to overshadow the effects from high school. This may be problematic because the perceived knowledge that leads to higher feelings of preparedness may not translate into appropriate actions in a real-life situation, potentially risking lives.

Pneumologische Rehabilitation bei ILD: Unmittelbar effektive Verbesserung der Lebensqualität, aber wie sieht es langfristig aus?

2021 ◽  
pp. 18-20
Author(s):  
Desiree Faccioli ◽  
Marc Spielmanns
Keyword(s):  
Outcome Measures ◽  
Pulmonary Rehabilitation ◽  
Real Life ◽  
Blood Gases ◽  
Interstitial Lung Diseases ◽  
Walking Distance ◽  
Long Term Effects ◽  
Success Predictors ◽  
Antifibrotic Therapy ◽  
Arterial Blood

<b>Background and aim:</b> Benefits of pulmonary rehabilitation in Interstitial Lung Diseases (ILD) have been reported. The aim of this large multicenter study was to identify the success predictors of pulmonary rehabilitation in a real-life setting. <b>Methods:</b> Data of 240 in-patients (110 idiopathic pulmonary fibrosis (IPF), 106 ILD other than IPF and 24 undetermined ILD) undergoing pulmonary rehabilitation in a 10-year period were retrospectively evaluated. Six minute walking distance (6MWT), body weight-walking distance product tests, dyspnoea and arterial blood gases were assessed at admission and discharge. Differences in post rehabilitation changes in outcome measures as function of baseline characteristics were evaluated. <b>Results:</b>After rehabilitation, patients showed improvements in all outcome measures (p &#x3c; 0.05), regardless of the underlying diagnosis or disease severity. Patients needing oxygen therapy at rest showed reduced benefits. Baseline 6MWD inversely correlated with its changes at discharge. Non-significant greater benefits after rehabilitation were found in IPF patients under antifibrotic therapy. In a subset of 50 patients assessed on average 10.3 ± 3.5 months after discharge, the benefits in 6MWD were not maintained (312.9 ± 139.4, 369.7 ± 122.5 and 310.8 ± 139.6 m at admission, discharge and follow up respectively: <i>p</i> &#x3c; 0.0001). <b>Conclusion:</b> Pulmonary rehabilitation may improve dyspnoea, exercise capacity and fatigue in patients with ILD of different aethiologies and level of severity. The long-term effects need to be established.

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