Clonal reproduction of Azolla filiculoides Lam.: implications for invasiveness

Clonal reproduction of Azolla filiculoides Lam., an aquatic floating fern, native from the American subtropics and a recent invader of Mediterranean wetlands, was assessed experimentally. Shoot fragmentation of the species was quantified under suitable room conditions for optimum growth. Azolla fililculoides showed high longevity, a low mortality percentage and a high potential for clonal reproduction (biomass obtained by shoot fragmentation from only one individual was multiplied by 100). This last attribute changed over time: first generations developed a high number of propagules, a number which decreased progressively in later generations until the end of the experiment. The results of this experiment will be useful for understanding Azolla’s success within invaded habitats

The invasion of Doñana National Park (SW Spain) by the mosquito fern (Azolla filiculoides Lam)

In 2001, Azolla filiculoides Lam., a floating pteridophyte native to the New World, was found in Doñana National Park (SW Spain), an European protected area well known for its high value from a conservation point of view and for its ecological vulnerability. Until that time, there had been no exotic aquatic macrophyte observations in the National Park. Since then, surfaces covered by Azolla filiculoides have increased explosively forming thick floating mats which eliminate submersed plants, and seriously threaten the aquatic ecosystems in this important protected area.En 2001, Azolla filiculoides Lam., una pteridófita acuática nativa del Nuevo Mundo, fue encontrada en el Parque Nacional de Doñana (SW España), un espacio protegido europeo bien conocido por su alto valor desde el punto de vista de la conservación y por su vulnerabilidad ecológica. Hasta ese momento, no se había observado ningún macrófito acuático exótico en el Parque Nacional; desde entonces, las superficies cubiertas por Azolla filiculoides se han incrementado de manera explosiva originando gruesas capas flotantes que eliminan las plantas acuáticas sumergidas y amenazan gravemente los ecosistemas acuáticos de este importante espacio protegido

Quality, oxidative markers and DNA damage (DNA) fragmentation of red deer thawed spermatozoa after incubation at 37 °C in presence of several antioxidants

P. 1005-1019Antioxidants may be useful for supplementing sperm extenders. We have tested dehydroascorbic acid (DHA), TEMPOL, N-acetyl-cysteine (NAC) and rutin on epididymal spermatozoa from red deer, during incubation at 37 °C. Cryopreserved spermatozoa were thawed, washed and incubated with 1 mm or 0.1 mm of each antioxidant, including oxidative stress (Fe2+/ascorbate). Motility (CASA and clustering of subpopulations), viability, mitochondrial membrane potential, and acrosomal status were assessed at 2 and 4 h. Lipoperoxidation, intracellular reactive oxygen species (ROS) and DNA damage (DNA) status (TUNEL) were checked at 4 h. Oxidative stress increased ROS, lipoperoxidation and DNA damage. Overall, antioxidants negatively affected motility and physiological parameters. Only DHA 1 mm protected motility, increasing the fast and progressive subpopulation. However, it had a detrimental effect on acrosomal and DNA status, in absence of oxidative stress. Tempol and rutin efficiently reduced lipoperoxidation, ROS, and DNA damage in presence of oxidative stress. NAC was not as efficient as TEMPOL or rutin reducing lipoperoxidation or protecting DNA, and did not reduce ROS, but its negative effects were lower than the other antioxidants when used at 1 mm, increasing the subpopulation of hyperactivated-like spermatozoa at 2 h. Our results show that these antioxidants have mixed effects when spermatozoa are incubated at physiological temperatures. DHA may not be suitable because of prooxidant effects, but TEMPOL, NAC and rutin may be considered for cryopreservation trials. In general, exposure of red deer spermatozoa to these antioxidants should be limited to low temperatures, when only protective effects may develop.S

Mitochondrial activity and forward scatter vary in necrotic, apoptotic and membrane-intact spermatozoan subpopulations

P. 547-556In the present study, we have related mitochondrial membrane potential (ΔΨm) and forward scatter (FSC) to apoptotic-related changes in spermatozoa. Thawed red deer spermatozoa were incubated in synthetic oviductal fluid medium (37°C, 5% CO2), with or without antioxidant (100 μm Trolox). At 0, 3, 6 and 9 h, aliquots were assessed for motility and were stained with a combination of Hoechst 33342, propidium ioide (PI), YO-PRO-1 and Mitotracker Deep Red for flow cytometry. The proportion of spermatozoa YO-PRO-1+ and PI+ (indicating a damaged plasmalemma; DEAD) increased, whereas that of YO-PRO-1– and PI– (INTACT) spermatozoa decreased. The proportion of YO-PRO-1+ and PI– spermatozoa (altered plasmalemma; APOPTOTIC) did not change. Both DEAD and APOPTOTIC spermatozoa had low ΔΨm. Most high-ΔΨm spermatozoa were INTACT, and their proportion decreased with time. The FSC signal also differed between different groups of spermatozoa, in the order APOPTOTIC > DEAD > INTACT/low ΔΨm > INTACT/high ΔΨm; however, the actual meaning of this difference is not clear. APOPTOTIC spermatozoa seemed motile at 0 h, but lost motility with time. Trolox only slightly improved the percentage of INTACT spermatozoa (P < 0.05). The population of APOPTOTIC spermatozoa in the present study may be dying cells, possibly with activated cell death pathways (loss of ΔΨm). We propose that the sequence of spermatozoon death here would be: (1) loss of ΔΨm; (2) membrane changes (YO-PRO-1+ and PI–); and (3) membrane damage (PI+). INTACT spermatozoa with low ΔΨm or altered FSC may be compromised cells. The present study is the first that directly relates membrane integrity, apoptotic markers and mitochondrial status in spermatozoa. The results of the present study may help us understand the mechanisms leading to loss of spermatozoon viability after thawing.S

Physical Fitness and Self-Rated Health in Children and Adolescents: Cross-Sectional and Longitudinal Study

Self-rated health (SRH) is an independent determinant for all-cause mortality. We aimed to examine the independent and combined associations of components of physical fitness with SRH at baseline (cross-sectional) and two years later (longitudinal) in children and adolescents. Spanish youth (N = 1378) aged 8 to 17.9 years participated at baseline. The dropout rate at 2-year follow-up was 19.5% (n = 270). Participants were categorized as either children (8 to 11.9 years age) or adolescents (12 to 17.9 years age). The ALPHA health- related fitness test battery for youth was used to assess physical fitness, and SRH was measured by a single-item question. Cumulative link, ANOVA and ANCOVA models were fitted to analyze the data. Cardiorespiratory fitness, relative upper body isometric muscular strength, muscular strength score, and global physical fitness were positively associated with SRH in children (OR, 1.048; 95% CI, 1.020-1.076; OR, 18.921; 95% CI, 3.47-104.355; OR, 1.213; 95% CI, 1.117-1.319, and OR, 1.170; 95% CI, 1.081-1.266, respectively; all p < 0.001) and adolescents (OR, 1.057; 95% CI, 1.037-1.076; OR, 5.707; 95% CI, 1.122-29.205; OR, 1.169; 95% CI, 1.070-1.278, and OR, 1.154 95% CI, 1.100-1.210, respectively; all p < 0.001); and motor fitness was positively associated with SRH only in adolescents at baseline (OR, 1.192; 95% CI, 1.066-1.309; p < 0.01). Cardiorespiratory fitness and global physical fitness were positively associated with SRH in children two years later (OR, 1.056; 95% CI, 1.023-1.091; p < 0.001; and OR, 1.082; 95% CI, 1.031-1.136; p < 0.01; respectively). Only cardiorespiratory fitness was independently associated with SRH in children and adolescents at baseline (OR, 1.059; 95% CI, 1.029-1.090; and OR, 1.073; 95% CI, 1.050-1.097, respectively; both p < 0.001) and two years later (OR, 1.075; 95% CI, 1.040-1.112; p < 0.001; and OR, 1.043; 95% CI, 1.014-1.074; p < 0.01, respectively). A high level of cardiorespiratory fitness at baseline or maintaining high levels of cardiorespiratory fitness from the baseline to 2-year follow-up were associated with a higher level of SRH at 2-year follow-up in children (p < 0.01) and adolescents (p < 0.05). These findings emphasize the importance of cardiorespiratory fitness as strong predictor of present and future SRH in youth. Intervention programs to enhance cardiorespiratory fitness level of the youth population are urgently needed for present and future youth's health

Comparative study of the primary cilia in thyrocytes of adult mammals

Since their discovery in different human tissues by Zimmermann in 1898, primary cilia have been found in the vast majority of cell types in vertebrates. Primary cilia are considered to be cellular antennae that occupy an ideal cellular location for the interpretation of information both from the environment and from other cells. To date, in mammalian thyroid gland, primary cilia have been found in the thyrocytes of humans and dogs (fetuses and adults) and in rat embryos. The present study investigated whether the existence of this organelle in follicular cells is a general event in the postnatal thyroid gland of different mammals, using both immunolabeling by immunofluorescence and electron microscopy. Furthermore, we aimed to analyse the presence of primary cilia in various thyroid cell lines. According to our results, primary cilia are present in the adult thyroid gland of most mammal species we studied (human, pig, guinea pig and rabbit), usually as a single copy per follicular cell. Strikingly, they were not found in rat or mouse thyroid tissues. Similarly, cilia were also observed in all human thyroid cell lines tested, both normal and neoplastic follicular cells, but not in cultured thyrocytes of rat origin. We hypothesize that primary cilia could be involved in the regulation of normal thyroid function through specific signaling pathways. Nevertheless, further studies are needed to shed light on the permanence of these organelles in the thyroid gland of most species during postnatal life.Junta de Andalucía. Consejería de Innovación, Ciencia y Empresa CTS-439/2011Junta de Andalucía. Consejería de Innovación, Ciencia y Empresa CTS-229/2011Junta de Andalucía. Consejería de Salud PI-0051-201

Criterion-Related Validity of Field-Based Fitness Tests in Adults: A Systematic Review

We comprehensively assessed the criterion-related validity of existing field-based fitness tests used to indicate adult health (19-64 years, with no known pathologies). The medical electronic databases MEDLINE (via PubMed) and Web of Science (all databases) were screened for studies published up to July 2020. Each original study's methodological quality was classified as high, low and very low, according to the number of participants, the description of the study population, statistical analysis and systematic reviews which were appraised via the AMSTAR rating scale. Three evidence levels were constructed (strong, moderate and limited evidence) according to the number of studies and the consistency of the findings. We identified 101 original studies (50 of high quality) and five systematic reviews examining the criterion-related validity of field-based fitness tests in adults. Strong evidence indicated that the 20 m shuttle run, 1.5-mile, 12 min run/walk, YMCA step, 2 km walk and 6 min walk test are valid for estimating cardiorespiratory fitness; the handgrip strength test is valid for assessing hand maximal isometric strength; and the Biering-Sorensen test to evaluate the endurance strength of hip and back muscles; however, the sit-and reach test, and its different versions, and the toe-to-touch test are not valid for assessing hamstring and lower back flexibility. We found moderate evidence supporting that the 20 m square shuttle run test is a valid test for estimating cardiorespiratory fitness. Other field-based fitness tests presented limited evidence, mainly due to few studies. We developed an evidence-based proposal of the most valid field-based fitness tests in healthy adults aged 19-64 years old.This project was supported by Ministry of Economy, Industry and Competitiveness in the 2017 call for R&D Projects of the State Program for Research, Development and Innovation Oriented to the Challenges of the Company; National Plan for Scientific and Technical Research and of Innovation 2017-2020 (DEP2017-88043-R); and the Regional Government of Andalusia and University of Cadiz: Research and Knowledge Transfer Fund (PPIT-FPI19)

Effect of different media additives on capacitation of frozen-thawed ram spermatozoa as a potential replacement for estrous sheep serum

Capacitation is a key process through which spermatozoa acquire their fertilizing ability. This event is required for the successful application of assisted reproductive technologies such as IVF. The aim of the present study was to investigate the effect of using a synthetic oviductal fluid medium supplemented with either heparin–hypotaurine alone, in combination with progesterone (P4), 17β-estradiol (E2), or BSA, or just β-cyclodextrin, in replacement for estrous sheep serum (ESS) for ram sperm capacitation. After incubation in the corresponding media for 15 (time 0) or 60 minutes, sperm function was evaluated by computerized sperm motility analysis and flow cytometry (plasma membrane status and fluidity). Treatments rendering the best results in regards to sperm function parameters related to capacitation were used for an IVF test. Herein, neither heparin–hypotaurine (alone), or in combination with P4, or E2, nor β-cyclodextrin induced capacitation-related changes in frozen–thawed ram spermatozoa. Only the medium supplemented with heparin–hypotaurine–BSA was able to induce changes compatible with in vitro capacitation relating to sperm motility pattern and plasma membrane fluidity, comparable to those in ESS-containing medium. Both media yielded sperm parameter values that differed (P < 0.05) from those obtained in the rest of the media tested. However, after the IVF trial, BSA was unable to support cleavage rates (21.80%) comparable to those obtained with ESS (52.60%; P < 0.05). We conclude that heparin–hypotaurine, P4, E2, β-cyclodextrin, or BSA is not suitable for replacing ESS in capacitation and fertilization media for ram spermatozoa.M. Ramón was supported by the Research Recruitment Program from the National Institute for Agricultural and Food Research program.Peer Reviewe

Flora y vegetación de la marisma de Doñana en el marco del proyecto de restauración ecológica Doñana 2005

Doñana 2005 is an ambitious ecological restoration project that is developed in the wetlands of the Doñana protected space (SW Spain). The objective of this article is to present the preliminary results of the Flora and Vegetation Team linked to the project. Floristic spectrum and phytogeographical elements from the flora of the study area are shown. Furthermore, data corresponding to the evolution of the land cover vegetation of the studied zones is offered.Doñana 2005 es un ambicioso proyecto de restauración ecológica que se desarrolla en el los humedales del espacio protegido de Doñana (SW España). El objetivo de este artículo es dar a conocer los resultados preliminares del Equipo de Flora y Vegetación vinculado a dicho proyecto. Se muestran el espectro florístico y los elementos fitogeográficos de la flora del área de estudio. Asimismo se ofrecen datos correspondientes a la evolución de la cubierta vegetal de las zonas estudiadas