Chromosome ends and the theory of marginotomy: implications for reproduction.

Telomeres are the protective structures located at the ends of linear chromosomes. They were first described in the 1930s, but their biology remained unexplored until the early 70s, when Alexey M. Olovnikov, a theoretical biologist, suggested that telomeres cannot be fully copied during DNA replication. He proposed a theory that linked this phenomenon with the limit of cell proliferation capacity and the "duration of life" (theory of marginotomy), and suggested a potential of telomere lenghthening for the prevention of aging (anti-marginotomy). The impact of proliferative telomere shortening on life expectancy was later confirmed. In humans, telomere shortening is counteracted by telomerase, an enzyme that is undetectable in most adult somatic cells, but present in cancer cells and adult and embryonic stem and germ cells. Although telomere length dynamics are different in male and female gametes during gametogenesis, telomere lengths are reset at the blastocyst stage, setting the initial length of the species. The role of the telomere pathway in reproduction has been explored for years, mainly because of increased infertility resulting from delayed childbearing. Short telomere length in ovarian somatic cells is associated to decreased fertility and higher aneuploidy rates in embryos. Consequently, there is a growing interest in telomere lengthening strategies, aimed at improving fertility. It has also been observed that lifestyle factors can affect telomere length and improve fertility outcomes. In this review, we discuss the implications of telomere theory in fertility, especially in oocytes, spermatozoa, and embryos, as well as therapies to enhance reproductive success.

Impaired telomere pathway and fertility in Senescence-Accelerated Mice Prone 8 females with reproductive senescence.

Ovarian aging is the main cause of infertility and telomere attrition is common to both aging and fertility disorders. Senescence-Accelerated Mouse Prone 8 (SAMP8) model has shortened lifespan and premature infertility, reflecting signs of reproductive senescence described in middle-aged women. Thus, our objective was to study SAMP8 female fertility and the telomere pathway at the point of reproductive senescence. The lifespan of SAMP8 and control mice was monitored. Telomere length (TL) was measured by in situ hybridization in blood and ovary. Telomerase activity (TA) was analyzed by telomere-repeat amplification protocol, and telomerase expression, by real-time quantitative PCR in ovaries from 7-month-old SAMP8 and controls. Ovarian follicles at different stages of maturation were evaluated by immunohistochemistry. Reproductive outcomes were analyzed after ovarian stimulation. Unpaired t-test or Mann-Whitney test were used to calculate p-values, depending on the variable distribution. Long-rank test was used to compare survival curves and Fisher's exact test was used in contingency tables. Median lifespan of SAMP8 females was reduced compared to SAMP8 males (p = 0.0138) and control females (p < 0.0001). In blood, 7-month-old SAMP8 females presented lower mean TL compared to age-matched controls (p = 0.041). Accordingly, the accumulation of short telomeres was higher in 7-month-old SAMP8 females (p = 0.0202). Ovarian TA was lower in 7-month-old SAMP8 females compared to controls. Similarly, telomerase expression was lower in the ovaries of 7-month-old SAMP8 females (p = 0.04). Globally, mean TL in ovaries and granulosa cells (GCs) were similar. However, the percentage of long telomeres in ovaries (p = 0.004) and GCs (p = 0.004) from 7-month-old SAMP8 females was lower compared to controls. In early-antral and antral follicles, mean TL of SAMP8 GCs was lower than in age-matched controls (p = 0.0156 for early-antral and p = 0.0037 for antral follicles). Middle-aged SAMP8 showed similar numbers of follicles than controls, although recovered oocytes after ovarian stimulation were lower (p = 0.0068). Fertilization rate in oocytes from SAMP8 was not impaired, but SAMP8 mice produced significantly more morphologically abnormal embryos than controls (27.03% in SAMP8 vs. 1.22% in controls; p < 0.001). Our findings suggest telomere dysfunction in SAMP8 females, at the time of reproductive senescence.

Juvenile idiopathic arthritis in the young adult. Methodology, objectives, and initial data from the JUVENSER registry.

OBJECTIVES: To describe the methodology, objectives, and initial data of the registry of young adult patients diagnosed with Juvenile Idiopathic Arthritis (JIA), JUVENSER. The main objective of the project is to know the sociodemographic and clinical characteristics, and disease activity of patients with JIA reaching the transition to adulthood. MATERIAL AND METHOD: Longitudinal, prospective, multicentre study, including patients between 16 and 25 years old, with a diagnosis of JIA in any of its categories. The main objective is to determine the characteristics and activity of JIA in the young adult. It includes sociodemographic variables, clinical variables, disease activity and joint damage rates, data on the use of health resources, and treatments used. The total duration of the project will be 3 years. A cohort of 534 young adult patients was obtained. CONCLUSIONS: The JUVENSER registry will constitute a cohort of young adults with JIA, which will allow the evaluation of the clinical characteristics and response to treatment of patients with disease onset in childhood, moving to adult clinics.

Effects of age and oligoasthenozoospermia on telomeres of sperm and blood cells.

RESEARCH QUESTION: How do age and normo- or oligoasthenozoospermia affect telomere length dynamics in spermatozoa and blood? DESIGN: Sperm and blood samples were collected from a cohort of 37 men aged 25 and under and 40 men aged 40 and over, with either normozoospermia (NZ) or oligoasthenozoospermia (OAZ). Telomere length was evaluated using quantitative fluorescence in-situ hybridization. Telomerase mRNA (TERC and TERT) and shelterin (TRF1) gene expression were analysed using quantitative real-time polymerase chain reaction. TRF1 protein immunoreactivity was also evaluated using immunofluorescence. RESULTS: Mean sperm telomere length (STL) increased with age in the NZ group; older NZ men accumulated the longest telomeres (P < 0.001). In peripheral blood mononuclear cells (PBMC), mean telomere length decreased with age in NZ groups, although not reaching statistical significance. Interestingly, the younger OAZ group had the shortest mean telomere length (versus young NZ, P = 0.0081; versus old NZ, P = 0.0116; versus old OAZ, P = 0.0009) and accumulated the highest percentage of short telomeres compared with the other groups (overall P = 0.0017). Analysis of TERC and TERT mRNA expression in spermatozoa and PBMC did not show significant differences among groups. Statistically significant positive correlations were found between STL and seminal parameters in younger NZ men (P = 0.009 for sperm count and P = 0.007 for total progressive motility). Protein immunoreactivity of TRF1 in blood was not significantly different in all groups analysed. CONCLUSIONS: The OAZ group did not show the increase of STL with age that is seen in NZ individuals, suggesting that telomere length elongation mechanisms fail in OAZ patients. In PBMC, younger OAZ individuals showed significantly shorter mean telomere length, suggesting that this parameter could be a good biomarker of OAZ in younger OAZ patients. Telomerase gene and TRF1 mRNA expression and TRF1 protein immunoreactivity did not differ significantly between groups, and so these factors cannot be used as OAZ biomarkers.

Reproductive aging and telomeres: Are women and men equally affected?

Successful reproduction is very important for individuals and for society. Currently, the human health span and lifespan are the object of intense and productive investigation with great achievements, compared to the last century. However, reproduction span does not progress concomitantly with lifespan. Reproductive organs age, decreasing the levels of sexual hormones, which are protectors of health through their action on several organs of the body. Thus, this is the starting point of the organismal decay and infertility. This starting point is easily detected in women. In men, it goes under the surface, undetected, but it goes, nevertheless. Regarding fertility, aging alters the hormonal equilibrium, decreases the potential of reproductive organs, diminishes the quality of the gametes and worsen the reproductive outcomes. All these events happen at a different pace and affecting different organs in women and men. The question is what molecular pathways are involved in reproductive aging and if there is a possible halting or even reversion of the aging events. Answers to all these points will be explained in the present review.

Netiquette: Ethic, Education, and Behavior on Internet-A Systematic Literature Review.

In this article, an analysis of the existing literature is carried out. It focused on the netiquette (country, date, objectives, methodological design, main variables, sample details, and measurement methods) included in the Web of Science and Scopus databases. This systematic review of the literature has been developed entirely according to the Preferred Reporting Items for Systematic Reviews (PRISMA). The initial search yielded 53 results, of which 18 exceeded the inclusion criteria and were analyzed in detail. These results show that this is a poorly defined line of research, both in theory and in practice. There is a need to update the theoretical framework and an analysis of the empirical proposals, whose samples are supported by students or similar. Knowing, understanding, and analyzing netiquette is a necessity in a society in which information and communication technologies (ICT) have changed the way of socializing and communicating. A new reality in which there is cyber-bullying, digital scams, fake news, and haters on social networks.

Impact of Ovarian Aging in Reproduction: From Telomeres and Mice Models to Ovarian Rejuvenation.

The trend in our society to delay procreation increases the difficulty to conceive spontaneously. Thus, there is a growing need to use assisted reproduction technologies (ART) to form a family. With advanced maternal age, ovaries not only produce a lower number of oocytes after ovarian stimulation but also a lower quality-mainly aneuploidies-requiring further complex analysis to avoid complications during implantation and pregnancy. Although there are different options to have a child at advanced maternal age (like donor eggs), this is not the preferred choice for most patients. Unless women had cryopreserved their eggs at a younger age, reproductive medicine should try to optimize their opportunities to become pregnant with their own oocytes, when chances of success are reasonable. Aging has many causes, but telomere attrition is ultimately one of the main pathways involved in this process. Several reports link telomere biology and reproduction, but the molecular reasons for the rapid loss of ovarian function at middle age are still elusive. This review will focus on the knowledge acquired during the last years about ovarian aging and disease, both in mouse models of reproductive senescence and in humans with ovarian failure, and the implication of telomeres in this process. In addition, the review will discuss recent results on ovarian rejuvenation, achieved with stem cell therapies that are currently under study, or ovarian reactivation by tissue fragmentation and the attempts to generate oocytes in vitro.

Consensus of the Spanish society of pediatric rheumatology for transition management from pediatric to adult care in rheumatic patients with childhood onset.

To develop recommendations on the transition from pediatric care to adult care in patients with chronic inflammatory rheumatic diseases with childhood onset based. Recommendations were generated following nominal group methodology and Delphi technique. A panel of 16 experts was established. A systematic literature review (on transitional care) and a narrative review were performed and presented to the panel in the first panel meeting to be discussed. A first draft of recommendations was generated and circulated. Focal groups with adolescents, young adults and parents were organized. In a second meeting, the focus group results along with the input from invited psychologist were used to establish definitive recommendations. Then, a Delphi process (two rounds) was carried out. A group of 72 pediatric and adult rheumatologists took part. Recommendations were voted from 1 (total disagreement) to 10 (total agreement). We defined agreement if at least 70 % voted ≥7. The level of evidence and grade or recommendation was assessed using the Oxford center for evidence-based medicine levels of evidence. Transition care was defined as a purposeful, planned process that addresses the medical, psychosocial and educational/vocational needs of adolescents and young adults with chronic inflammatory rheumatic diseases with childhood onset as they move from child-centered to adult-oriented healthcare systems. The consensus covers: transition needs, barriers and facilitators, transitional issues (objectives, participants, content, phases, timing, plans, documentation and responsibilities), physicians' and other health professionals' knowledge and skill requirements, models/programs, and strategies and guideline for implementation. Preliminary recommendations and agreement grade are shown in the Table (first Delphi round). These recommendations are intended to provide health professionals, patients, families and other stakeholders with a consensus on the transition process from pediatric to adult care.

[Reactivation of hepatitis B in a patient with spondyloarthritis after the suspension of methotrexate and efficacy of treatment with antivirals in association to adalimumab]. / Reactivación de hepatitis B en un paciente con espondiloartritis tras suspender metotrexato y eficacia del tratamiento con antivirales en asociación con adalimumab.

We report the case of a male chronic hepatitis B virus (HBV) carrier with HLA-B27 spondyloarthrititis who developed fulminant hepatitis after discontinuation of methotrexate (MTX). Full recovery after therapy with lamivudine and adefovir allowed treatment with adalimumab which was well tolerated. Reactivation of hepatitis B after MTX withdrawal is a very rare complication, which can also occur in association with anti-TNF agents. In patients with positive serology for HBV prophylactic antiviral therapy is recommended.