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1.
PeerJ ; 12: e17161, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38560466

RESUMEN

The life history of a parasite describes its partitioning of assimilated resources into growth, reproduction, and transmission effort, and its precise timing of developmental events. The life cycle, in contrast, charts the sequence of morphological stages from feeding to the transmission forms. Phenotypic plasticity in life history traits can reveal how parasites confront variable environments within hosts. Within the protist phylum Apicomplexa major clades include the malaria parasites, coccidians, and most diverse, the gregarines (with likely millions of species). Studies on life history variation of gregarines are rare. Therefore, life history traits were examined for the gregarine Monocystis perplexa in its host, the invasive earthworm Amynthas agrestis at three sites in northern Vermont, United States of America. An important value of this system is the short life-span of the hosts, with only seven months from hatching to mass mortality; we were thus able to examine life history variation during the entire life cycle of both host and parasite. Earthworms were collected (N = 968 over 33 sample periods during one host season), then parasites of all life stages were counted, and sexual and transmission stages measured, for each earthworm. All traits varied substantially among individual earthworm hosts and across the sites. Across sites, timing of first appearance of infected earthworms, date when transmission stage (oocysts packed within gametocysts) appeared, date when number of both feeding (trophic) cells and gametocysts were at maximum, and date when 100% of earthworms were infected differed from 2-8 weeks, surprising variation for a short season available for parasite development. The maximal size of mating cells varied among hosts and across sites and this is reflected in the number of oocysts produced by the gametocyst. A negative trade-off was observed for the number of oocysts and their size. Several patterns were striking: (1) Prevalence reached 100% at all sites by mid season, only one to three weeks after parasites first appeared in the earthworms. (2) The number of parasites per host was large, reaching 300 × 103 cells in some hosts, and such high numbers were present even when parasites first appeared in the host. (3) At one site, few infected earthworms produced any oocysts. (4) The transmission rate to reach such high density of parasites in hosts needed to be very high for a microbe, from >0.33% to >34.3% across the three sites. Monocystis was one of the first protist parasites to have its life cycle described (early 19th century), but these results suggest the long-accepted life cycle of Monocystis could be incomplete, such that the parasites may be transmitted vertically (within the earthworm's eggs) as well as horizontally (leading to 100% prevalence) and merogony (asexual replication) could be present, not recognized for Monocystis, leading to high parasitemia even very early in the host's season.


Asunto(s)
Apicomplexa , Rasgos de la Historia de Vida , Oligoquetos , Parásitos , Animales , Oligoquetos/parasitología , Reproducción , Estadios del Ciclo de Vida , Oocistos
2.
PeerJ ; 12: e17118, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38562996

RESUMEN

Cooperation is widespread across life, but its existence can be threatened by exploitation. The rise of obligate social cheaters that are incapable of contributing to a necessary cooperative function can lead to the loss of that function. In the social amoeba Dictyostelium discoideum, obligate social cheaters cannot form dead stalk cells and in chimeras instead form living spore cells. This gives them a competitive advantage within chimeras. However, obligate cheaters of this kind have thus far not been found in nature, probably because they are often enough in clonal populations that they need to retain the ability to produce stalks. In this study we discovered an additional cost to obligate cheaters. Even when there are wild-type cells to parasitize, the chimeric fruiting bodies that result have shorter stalks and these are disadvantaged in spore dispersal. The inability of obligate cheaters to form fruiting bodies when they are on their own combined with the lower functionality of fruiting bodies when they are not represent limits on obligate social cheating as a strategy.


Asunto(s)
Amoeba , Dictyostelium , Reproducción , Esporas Protozoarias
4.
C R Biol ; 347: 19-25, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38639155

RESUMEN

Polycystic ovary syndrome (PCOS) is the most common endocrine and metabolic disorder in women of reproductive age. It has a strong hereditary component estimated at 60 to 70% in daughters. It has been suggested that environmental factors during the fetal period may be involved in the development of the syndrome in adulthood. However, the underlying mechanisms of its transmission remain unknown, thus limiting the development of effective therapeutic strategies.This article highlights how an altered fetal environment (prenatal exposure to high levels of anti-Müllerian hormone) can contribute to the onset of PCOS in adulthood and lead to the transgenerational transmission of neuroendocrine and metabolic traits through alterations in the DNA methylation process.The originality of the translational findings summarized here involves the identification of potential biomarkers for early diagnosis of the syndrome, in addition to the validation of a promising therapeutic avenue in a preclinical model of PCOS, which can improve the management of patients suffering from the syndrome.


Le syndrome des ovaires polykystiques (SOPK) est le trouble endocrinien et métabolique le plus répandu chez les femmes en âge de procréer, avec une forte composante héréditaire estimée entre 60 et 70%. Les facteurs environnementaux pendant la période fœtale pourraient être impliqués dans l'apparition du syndrome à l'âge adulte. Néanmoins, les mécanismes sous-jacents à sa transmission demeurent inconnus, limitant ainsi le développement de thérapies efficaces.Cet article met en lumière comment un environnement fœtal altéré (exposition prénatale à des taux élevés d'hormone anti-müllerienne) pourrait contribuer à la survenue du SOPK chez la descendance ainsi qu'à la transmission transgénérationnelle des caractéristiques neuroendocriniennes et métaboliques du SOPK, par le biais d'une altération du processus de la méthylation de l'ADN.L'originalité des travaux translationnels présentés ici repose d'une part sur l'identification de potentiels biomarqueurs de diagnostic précoce du syndrome. Et d'autre part, sur la validation d'une piste thérapeutique prometteuse dans un modèle préclinique de SOPK, offrant ainsi des perspectives d'amélioration de la prise en charge des patientes atteintes de ce syndrome.


Asunto(s)
Síndrome del Ovario Poliquístico , Embarazo , Femenino , Humanos , Síndrome del Ovario Poliquístico/etiología , Síndrome del Ovario Poliquístico/genética , Fenotipo , Hormona Antimülleriana , Reproducción
5.
Hastings Cent Rep ; 54(2): 34-43, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38639162

RESUMEN

I consider the question of what moral obligations prospective parents owe to their future children. It is taken as an almost axiomatic premise of a wide range of philosophical arguments that prospective parents have a moral obligation to take such steps as ensuring their own financial stability or waiting until they are emotionally mature before conceiving. This is because it is assumed that parents have a moral obligation to lay the groundwork for their children's lives to go well. While at first glance such a premise seems benign, I will argue that when it is applied to arguments in assisted reproductive technology, as it is in Julian Savulescu's procreative beneficence argument or as it is in Daniel Groll's recent argument for open gamete donation, we see problems with this premise. Problems in Groll's argument also become apparent when it is scrutinized in connection with this premise.


Asunto(s)
Diagnóstico Preimplantación , Embarazo , Niño , Femenino , Humanos , Estudios Prospectivos , Reproducción , Técnicas Reproductivas Asistidas , Padres , Obligaciones Morales
6.
Development ; 151(7)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38603796

RESUMEN

Embryonic diapause is a special reproductive phenomenon in mammals that helps embryos to survive various harsh stresses. However, the mechanisms of embryonic diapause induced by the maternal environment is still unclear. Here, we uncovered that nutrient deficiency in uterine fluid was essential for the induction of mouse embryonic diapause, shown by a decreased concentration of arginine, leucine, isoleucine, lysine, glucose and lactate in the uterine fluid of mice suffering from maternal starvation or ovariectomy. Moreover, mouse blastocysts cultured in a medium with reduced levels of these six components could mimic diapaused blastocysts. Our mechanistic study indicated that amino acid starvation-dependent Gator1 activation and carbohydrate starvation-dependent Tsc2 activation inhibited mTORC1, leading to induction of embryonic diapause. Our study elucidates the essential environmental factors in diapause induction.


Asunto(s)
Diapausa , Desarrollo Embrionario , Femenino , Animales , Ratones , Desarrollo Embrionario/fisiología , Blastocisto/metabolismo , Reproducción , Diapausa/fisiología , Nutrientes , Mamíferos
8.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1485-1493, 2024 Mar.
Artículo en Chino | MEDLINE | ID: mdl-38621932

RESUMEN

Chuanxiong Rhizoma is a well-known Sichuan-specific herbal medicine. Its original plant, Ligusticum chuanxiong, has been cultivated asexually for a long time. L. chuanxiong has sexual reproductive disorders, which restricts its germplasm innovation. However, there is little research on the reproductive system of L. chuanxiong. This study is based on a comparative anatomical research approach, using morphological dissection, paraffin sectioning, staining and compression, and combined with scanning electron microscopy technology, to observe and compare the flowers, fruits, and seeds at various stages of reproductive growth of L. chuanxiong and its wild relative L. sinense. The results showed that the meiosis of pollen mother cells is abnormal in L. chuanxiong anthers, and the size and number of microspores are uneven and inconsistent in the tetrad stage. tapetum cells are not completely degenerated during anther development. During the pollen ripening stage, there are fine cracks in the anther wall, while most anthers could not release pollen normally. The surface of mature pollen grains is concave and partially deformed, and the pollens are all inactive and cannot germinate in vitro. The starch, polysaccharides, and lipids in the pollen were insufficient. The filaments of L. chuanxiong are short at the flowering stage and recurved downward. Double-hanging fruits were observed in the fruiting stage, being wrinkled; with shriveled seeds. Compared with L. sinense at the same stage, the anthers of L. sinense developed normally, and the pollen grains are vigorous and can germinate in vitro. The double-hanging fruits of L. sinense are full and normal; at the flowering period, the filaments are long and erect, significantly higher than the stigma. Mature blastocysts are visible in the ovary of both L. chuanxiong and L. sinense, and there is no significant difference in stigmas. The conclusion is that during the development of L. chuanxiong stamens, the meiosis of pollen mother cells is abnormal, and tetrad, tapetum, filament and other pollen structures develop abnormally. L. chuanxiong has the characteristic of male infertility, which is an important reason for its sexual reproductive disorders.


Asunto(s)
Ligusticum , Reproducción , Polen , Flores , Polisacáridos
9.
Psychooncology ; 33(4): e6323, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38629761

RESUMEN

OBJECTIVE: Many young adult female cancer survivors need to use reproductive medicine, surrogacy, or adoption to have a child. This study pilot tested Roadmap to Parenthood, a web-based, self-guided decision aid and planning tool for family building after cancer (disease agnostic). METHODS: A single-arm pilot study tested feasibility, acceptability, and obtained effect size estimates of the Roadmap tool. Participants, recruited via hospital-based and social media strategies, completed a baseline survey (T1), accessed the Roadmap tool (website), then completed surveys at one- and 3-months (T2 and T3, respectively). Feasibility and acceptability were evaluated with rates of eligibility, enrollment, and survey completion, and feedback. Pairwise t-tests and repeated measures ANOVA evaluated usage effects. Effect size estimates were calculated. RESULTS: Participants (N = 98) averaged 31 years old (SD = 5.61); 71% were nulliparous. Enrollment rate was 73%, T1-T2 completion rate was 80%, and 93% accessed the website. From T1-T2, participants reported improvements in decisional conflict (p < 0.001; Cohen's d = 0.85), unmet information needs (p < 0.001; Cohen's d = 0.70), self-efficacy (p = 0.003; Cohen's d = 0.40), and self-efficacy for managing negative emotions (p = 0.03; Cohen's d = 0.29); effects were sustained at T3. There was no change in reproductive distress (p = 0.22). By T3, 94% reported increased consideration of preparatory actions and 20%-61% completed such actions. CONCLUSIONS: The Roadmap intervention was feasible to conduct, acceptable to users, and led to improvements in key psychosocial outcomes. Future directions will test intervention efficacy in a randomized controlled trial with a larger sample and over a longer period. A web-based tool may help women make decisions about family building after cancer and prepare for potential challenges.


Asunto(s)
Supervivientes de Cáncer , Neoplasias , Adulto , Femenino , Humanos , Adulto Joven , Supervivientes de Cáncer/psicología , Técnicas de Apoyo para la Decisión , Neoplasias/terapia , Neoplasias/psicología , Proyectos Piloto , Reproducción
10.
Am Nat ; 203(5): E157-E174, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38635358

RESUMEN

AbstractAssessing whether phenological shifts in response to climate change confer a fitness advantage requires investigating the relationships among phenology, fitness, and environmental drivers of selection. Despite widely documented advancements in phenology with warming climate, we lack empirical estimates of how selection on phenology varies in response to continuous climate drivers or how phenological shifts in response to warming conditions affect fitness. We leverage an unusual long-term dataset with repeated, individual measurements of phenology and reproduction in a long-lived alpine plant. We analyze phenotypic plasticity in flowering phenology in relation to two climate drivers, snowmelt timing and growing degree days (GDDs). Plants flower earlier with increased GDDs and earlier snowmelt, and directional selection also favors earlier flowering under these conditions. However, reproduction still declines with warming and early snowmelt, even when flowering is early. Furthermore, the steepness of this reproductive decline increases dramatically with warming conditions, resulting in very little fruit production regardless of flowering time once GDDs exceed approximately 225 degree days or snowmelt occurs before May 15. Even though advancing phenology confers a fitness advantage relative to stasis, these shifts are insufficient to maintain reproduction under warming, highlighting limits to the potential benefits of phenological plasticity under climate change.


Asunto(s)
Cambio Climático , Flores , Estaciones del Año , Temperatura , Flores/fisiología , Reproducción , Plantas
11.
Am Nat ; 203(5): 576-589, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38635359

RESUMEN

AbstractLong-term social and genetic monogamy is rare in animals except birds, but even in birds it is infrequent and poorly understood. We investigated possible advantages of monogamy in a colonial, facultative cooperatively breeding bird from an arid, unpredictable environment, the sociable weaver (Philetairus socius). We documented divorce and extrapair paternity of 703 pairs over 10 years and separated effects of pair duration from breeding experience by analyzing longitudinal and cross-sectional datasets. Parts of the colonies were protected from nest predation, thereby limiting its stochastic and thus confounding effect on fitness measures. We found that 6.4% of sociable weaver pairs divorced and 2.2% of young were extrapair. Longer pair-bonds were associated with more clutches and fledglings per season and with reproducing earlier and later in the season, when snake predation is lower, but not with increased egg or fledgling mass or with nestling survival. Finally, the number of helpers at the nest increased with pair-bond duration. Results were similar for protected and unprotected nests. We suggest that long-term monogamy is associated with a better capacity for exploiting a temporally unpredictable environment and helps to form larger groups. These results can contribute to our understanding of why long-term monogamy is frequently associated with unpredictable environments and cooperation.


Asunto(s)
Apareamiento , Gorriones , Animales , Estudios Transversales , Conducta Predatoria , Reproducción
12.
Am Nat ; 203(5): 562-575, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38635362

RESUMEN

AbstractIn species with resource-defense mating systems (such as most temperate-breeding songbirds), male dispersal is often considered to be limited in both frequency and spatial extent. When dispersal occurs within a breeding season, the favored explanation is ecological resource tracking. In contrast, movements of male birds associated with temporary emigration, such as polyterritoriality (i.e., defense of an additional location after attracting a female in the initial territory), are usually attributed to mate searching. We suggest that male dispersal and polyterritoriality are functionally related and that mate searching may be a unifying hypothesis for predicting the within-season movements of male songbirds. Here, we test three key predictions derived from this hypothesis in Wood Warblers (Phylloscopus sibilatrix). We collected data on the spatial behavior of 107 males between 2017 and 2019 and related male movements to a new territory (in both a dispersal and a polyterritorial context) to mating potential in the current territory. Most males dispersed from their territories within days or weeks after failing to attract a female, despite occupying territories in apparently suitable habitat. Probability of polyterritoriality by paired males increased after the peak fertile period of their mate. Males never dispersed following nest predation if the female remained to renest. Thus, our data are consistent with the hypothesis that both movement types are functionally related to mate searching.


Asunto(s)
Pájaros Cantores , Animales , Femenino , Masculino , Conducta Sexual Animal , Estaciones del Año , Ecosistema , Reproducción
13.
Am Nat ; 203(5): 590-603, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38635363

RESUMEN

AbstractThe mechanisms underlying the divergence of reproductive strategies between closely related species are still poorly understood. Additionally, it is unclear which selective factors drive the evolution of reproductive behavioral variation and how these traits coevolve, particularly during early divergence. To address these questions, we quantified behavioral differences in a recently diverged pair of Nova Scotian three-spined stickleback (Gasterosteus aculeatus) populations, which vary in parental care, with one population displaying paternal care and the other lacking this. We compared both populations, and a full reciprocal F1 hybrid cross, across four major reproductive stages: territoriality, nesting, courtship, and parenting. We identified significant divergence in a suite of heritable behaviors. Importantly, F1 hybrids exhibited a mix of behavioral patterns, some of which suggest sex linkage. This system offers fresh insights into the coevolutionary dynamics of reproductive behaviors during early divergence and offers support for the hypothesis that coevolutionary feedback between sexual selection and parental care can drive rapid evolution of reproductive strategies.


Asunto(s)
Reproducción , Smegmamorpha , Animales , Territorialidad , Smegmamorpha/genética , Selección Sexual
14.
PLoS One ; 19(4): e0300398, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38635674

RESUMEN

Nectar robbing is common in angiosperms, especially in long tubular flowers or flowers with spurs that keep nectar out of reach of visitors. However, the robbing behaviour of bees is less understood. Here, we studied the sesame visitors, their robbing behaviour, and the impacts of robbing on plant reproductive fitness. Diverse insect species (primarily members of Hymenoptera) visited sesame flowers. The most effective pollinators were Amegilla zonata, Apis cerana, Apis dorsata, Apis florea, Ceratina binghami, Halictus acrocephalus and Xylocopa amethystina. Almost all visitors with variable percentages revealed the nectar-robbing phenomenon. Robbing activity depended on a complex of multiple attributes, including the visitor's body size, the corolla tube length, the availability and accessibility of nectar, and the resource-collecting task allocation of bees. Robbing activity varied according to flower-visiting species, flowering period and daytime. Robbing was comparatively higher in the late flowering period at 10.00-14.00 h. In the case of robbing visits, flower handling time was lower, and the visitation rate remained higher than non-robbing visits. Robbing visits did not significantly affect fruit and seed sets of sesame. Therefore, we can interpret the nectar-robbing interactions on sesame as commensal, with pollinators benefitting without altering the plant's reproductive fitness.


Asunto(s)
Néctar de las Plantas , Sesamum , Abejas , Animales , Polinización , Flores , Reproducción
15.
Elife ; 122024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38564239

RESUMEN

We have previously shown that after few seconds of adaptation by finger-tapping, the perceived numerosity of spatial arrays and temporal sequences of visual objects displayed near the tapping region is increased or decreased, implying the existence of a sensorimotor numerosity system (Anobile et al., 2016). To date, this mechanism has been evidenced only by adaptation. Here, we extend our finding by leveraging on a well-established covariance technique, used to unveil and characterize 'channels' for basic visual features such as colour, motion, contrast, and spatial frequency. Participants were required to press rapidly a key a specific number of times, without counting. We then correlated the precision of reproduction for various target number presses between participants. The results showed high positive correlations for nearby target numbers, scaling down with numerical distance, implying tuning selectivity. Factor analysis identified two factors, one for low and the other for higher numbers. Principal component analysis revealed two bell-shaped covariance channels, peaking at different numerical values. Two control experiments ruled out the role of non-numerical strategies based on tapping frequency and response duration. These results reinforce our previous reports based on adaptation, and further suggest the existence of at least two sensorimotor number channels responsible for translating symbolic numbers into action sequences.


Asunto(s)
Individualidad , Reproducción , Humanos , Movimiento (Física) , Análisis de Componente Principal
16.
Proc Biol Sci ; 291(2020): 20232946, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38565156

RESUMEN

Telomere length (TL) is a biomarker hypothesized to capture evolutionarily and ecologically important physiological costs of reproduction, infection and immunity. Few studies have estimated the relationships among infection status, immunity, TL and fitness in natural systems. The hypothesis that short telomeres predict reduced survival because they reflect costly consequences of infection and immune investment remains largely untested. Using longitudinal data from a free-living Soay sheep population, we tested whether leucocyte TL was predicted by infection with nematode parasites and antibody levels against those parasites. Helminth parasite burdens were positively associated with leucocyte TL in both lambs and adults, which is not consistent with TL reflecting infection costs. We found no association between TL and helminth-specific IgG levels in either young or old individuals which suggests TL does not reflect costs of an activated immune response or immunosenescence. Furthermore, we found no support for TL acting as a mediator of trade-offs between infection, immunity and subsequent survival in the wild. Our results suggest that while variation in TL could reflect short-term variation in resource investment or environmental conditions, it does not capture costs of infection and immunity, nor does it behave like a marker of an individual's helminth-specific antibody immune response.


Asunto(s)
Helmintos , Oveja Doméstica , Animales , Ovinos , Acortamiento del Telómero , Reproducción , Telómero
17.
Proc Biol Sci ; 291(2020): 20232546, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38565153

RESUMEN

Fossilized mating insects are irreplaceable material for comprehending the evolution of the mating behaviours and life-history traits in the deep-time record of insects as well as the potential sexual conflict. However, cases of mating pairs are particularly rare in fossil insects, especially aquatic or semi-aquatic species. Here, we report the first fossil record of a group of water striders in copulation (including three pairs and a single adult male) based on fossils from the mid-Cretaceous of northern Myanmar. The new taxon, Burmogerris gen. nov., likely represents one of the oldest cases of insects related to the marine environment, such as billabongs formed by the tides. It exhibits conspicuous dimorphism associated with sexual conflict: the male is equipped with a specialized protibial comb as a grasping apparatus, likely representing an adaptation to overcome female resistance during struggles. The paired Burmogerris show smaller males riding on the backs of the females, seemingly recording a scene of copulatory struggles between the sexes. Our discovery reveals a mating system dominated by males and sheds light on the potential sexual conflicts of Burmogerris in the Cretaceous. It indicates the mating behaviour remained stable over long-term geological time in these water-walking insects.


Asunto(s)
Ámbar , Rasgos de la Historia de Vida , Animales , Femenino , Masculino , Insectos , Reproducción , Copulación , Fósiles , Mianmar
18.
PLoS One ; 19(4): e0297362, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38568993

RESUMEN

BACKGROUND: Toxoplasma gondii (T. gondii) is a worldwide distributed protozoan parasite which has infected a wide range of warm-blooded animals and humans. The most common form of T. gondii infection is asymptomatic (latent); nevertheless, latent toxoplasmosis can induce various alterations of sex hormones, especially testosterone, in infected humans and animals. On the other hand, testosterone is involved in behavioral traits and reproductive functions in both sexes. Hence, the purpose of this systematic review is to summarize the available evidence regarding the association between T. gondii infection and testosterone alteration. METHODS: In the setting of a systematic review, an electronic search (any date to 10 January 2023) without language restrictions was performed using Science Direct, Web of Science, PubMed, Scopus, and Google Scholar. The PRISMA guidelines were followed. Following the initial search, a total of 12,306 titles and abstracts were screened initially; 12,281 were excluded due to the lack of eligibility criteria or duplication. Finally, 24 articles met the included criteria. A mean±standard deviation (SD) was calculated to assess the difference of testosterone between T. gondii positive and T. gondii negative humans. The possibility of publication bias was assessed using Egger's regression. P-value < 0.05 was considered statistically significant. RESULTS: This systematic review identified 24 articles (18 studies in humans and six studies in animals). Most human studies (13 out of 19) reported an increased level of testosterone following latent toxoplasmosis in males, while three studies reported decreased levels and two studies reported an insignificant change. Eleven articles (seven datasets in males and seven datasets in females) were eligible to be included in the data synthesis. Based on the random-effects model, the pooled mean± SD of testosterone in T. gondii positive than T. gondii negative was increased by 0.73 and 0.55 units in males and females, respectively. The Egger's regression did not detect a statistically significant publication bias in males and females (p = value = 0.95 and 0.71), respectively. Three studies in male animals (rats, mice, and spotted hyenas) and two studies in female animals (mice and spotted hyenas) reported a decline in testosterone in infected compared with non-infected animals. While, one study in female rats reported no significant changes of testosterone in infected than non-infected animals. Moreover, two studies in male rats reported an increased level of testosterone in infected than non-infected animals. CONCLUSIONS: This study provides new insights about the association between T. gondii infection and testosterone alteration and identifies relevant data gaps that can inform and encourage further studies. The consequence of increased testosterone levels following T. gondii infection could partly be associated with increased sexual behavior and sexual transmission of the parasite. On the other hand, declining testosterone levels following T. gondii infection may be associated with male reproductive impairments, which were observed in T. gondii-infected humans and animals. Furthermore, these findings suggest the great need for more epidemiological and experimental investigations in depth to understand the relationship between T. gondii infection and testosterone alteration alongside with future consequences of testosterone alteration.


Asunto(s)
Hyaenidae , Toxoplasma , Toxoplasmosis , Masculino , Humanos , Femenino , Animales , Ratones , Ratas , Testosterona , Toxoplasmosis/parasitología , Reproducción , Estudios Seroepidemiológicos
19.
BMC Womens Health ; 24(1): 222, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38581038

RESUMEN

BACKGROUND: The evidence regarding the association of reproductive factors with cardiovascular diseases (CVDs) is limited. AIMS: To investigate the relationship of reproductive factors with the risk of CVDs, as well as all-cause and cardiovascular mortality. METHODS: This study included 16,404 adults with reproductive factors from the National Health and Nutrition Examination Survey (NHANES) and followed up until 31 December 2019. Logistic models and restricted cubic spline models were used to assess the association of reproductive factors with CVDs. COX proportional hazards models and restricted cubic spline models, with adjustment for potential confounding, were employed to analyze the relation between reproductive factors and cardiovascular and all-cause death. RESULTS: There is a nonlinear relationship between age at menarche and CVDs. Age at menopause ≤ 11(OR 1.36, 95% CI 1.10-1.69) was associated with an increased risk of CVDs compared to ages 12-13 years. Age at Menopause ≤ 44 (OR 1.69, 95% CI 1.40-2.03) was associated with increased CVDs compared to age 35-49 years. Number of pregnancies ≥ 5(OR 1.26, 95% CI 1.02-1.55) was associated with an increased risk of CVDs compared to one pregnancy. In continuous variable COX regression models, a later age at menopause (HR 0.98, 95% CI 0.97-0.99) and a longer reproductive lifespan (HR 0.98, 95% CI 0.97-0.99) were associated with a decreased risk of all-cause death. A later age at menopause (HR 0.98, 95% CI 0.97-0.99) and a longer reproductive lifespan (HR 0.98, 95% CI 0.97-0.99) were associated with a decreased risk of cardiac death. CONCLUSIONS: Female reproductive factors are significant risk factors for CVDs American women.


Asunto(s)
Enfermedades Cardiovasculares , Embarazo , Adulto , Femenino , Estados Unidos/epidemiología , Humanos , Niño , Adolescente , Persona de Mediana Edad , Encuestas Nutricionales , Menopausia , Reproducción , Factores de Riesgo
20.
Nutrients ; 16(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38613041

RESUMEN

The role of minerals in female fertility, particularly in relation to the menstrual cycle, presents a complex area of study that underscores the interplay between nutrition and reproductive health. This narrative review aims to elucidate the impacts of minerals on key aspects of the reproductive system: hormonal regulation, ovarian function and ovulation, endometrial health, and oxidative stress. Despite the attention given to specific micronutrients in relation to reproductive disorders, there is a noticeable absence of a comprehensive review focusing on the impact of minerals throughout the menstrual cycle on female fertility. This narrative review aims to address this gap by examining the influence of minerals on reproductive health. Each mineral's contribution is explored in detail to provide a clearer picture of its importance in supporting female fertility. This comprehensive analysis not only enhances our knowledge of reproductive health but also offers clinicians valuable insights into potential therapeutic strategies and the recommended intake of minerals to promote female reproductive well-being, considering the menstrual cycle. This review stands as the first to offer such a detailed examination of minerals in the context of the menstrual cycle, aiming to elevate the understanding of their critical role in female fertility and reproductive health.


Asunto(s)
Ciclo Menstrual , Ovulación , Femenino , Humanos , Reproducción , Minerales , Conocimiento
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