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This article discusses a study conducted at the Fetal Medicine Unit of the University of Chile Hospital between 2018 and 2020. The study aimed to determine the impact of changes in the uterine artery pulsatility index (UtA-PI) on the outcomes of pregnant women using aspirin to prevent preterm pre-eclampsia (PE). The study found that pregnant women at high risk of preterm PE who were treated with aspirin had greater uterine artery vasodilation between the first and second trimesters compared to control pregnant women. However, further research with a larger sample size is needed to confirm these findings. [Extracted from the article]

This article presents a study conducted at the Fetal Medicine Unit of Hospital Clínico de la Universidad de Chile, aiming to develop a predictive model for assessing the risk of trisomy 21 (T21) between 20 to 25 weeks of gestation. The study included 3,125 singleton pregnancies and utilized a combination of categorical and quantitative markers such as maternal age, nasal bone length, prenasal thickness, and others. The multivariate model demonstrated a sensitivity of 70.6% and a false positive rate of 2.5%, with an area under the curve (AUC) of 0.975. The integration of second trimester markers with a quantitative approach was found to facilitate personalized T21 risk prediction during this gestational period. [Extracted from the article]

This article discusses a study that evaluated the performance of new craniofacial markers for predicting Trisomy 21 (T21) during second trimester screening ultrasounds. The study included singleton pregnancies at the Fetal Medicine Unit of Hospital Clínico de la Universidad de Chile between 2004 and 2017. The researchers found that certain craniofacial markers, including prenasal thickness (PNT) and nasal bone length (NBL), were higher in fetuses with T21 compared to euploid fetuses. However, the researchers concluded that further development of reference curves based on the local population is necessary for the utilization of these markers. [Extracted from the article]

To evaluate the impact on perinatal outcomes related with placental insufficiency, by the application of the new 2017 ACC/AHA guidelines to a group of chronic hypertensive pregnancies during their first trimester assessment. The best multivariate predictive model for p-PE included a previous PE background (OR = 15) and mean arterial pressure in mmHg (OR = 1.1). EP01.38: Perinatal outcomes of pregestational hypertension according to blood pressure range at 11-14-week scan: impact of the 2017 ACC/AHA guidelines. [Extracted from the article]

EP01.11: Risk of pre-eclampsia according to blood pressure range at 11-14-week scan in a very low-risk population: impact of AHA/ACC 2017 classification Blood pressure (BP) was measured just before the 11 to 14 weeks' ultrasound, and BP range was performed according to the AHA/ACC 2017 classification, as follows: normotensive (< 120/80 mmHg), elevated (120-129 / < 80 mmHg), stage 1 (130-139/80-89 mmHg) and stage 2 (>= 140 and/or 90 mmHg). To estimate the risk of global and preterm pre-eclampsia (PE) according to blood pressure range at first trimester scan in a very low-risk population. [Extracted from the article]

Eight microsatellite markers have been characterized from the Perumytilus purpuratus genome. Their gene diversity ranged from 0.057 to 0.873 and significant interpopulation genic heterogeneity was observed between two populations of southeastern Pacific (Chile) and southwestern Atlantic (Argentine). Distinct cross-priming amplification rates were recovered on nine additional species belonging to six Mytilinae genera. The microsatellites developed herein would likely be a powerful intraspecific genetic tool to undertake fine population studies in the intertidal ecosystem bioengineer P. purpuratus along the South American shoreline. [ABSTRACT FROM AUTHOR]

Several years of sea surface temperature data (1997-2003) for the coast of Antofagasta Bay—a semi-enclosed bay in northern Chile—were analyzed in order to further exploring the nature of a warm-water retention pattern inside the bay. Based on time series techniques, we were able to confirm the persistence of warm water in the bay. This warm feature was found immediately downwind of the upwelling center at Jorgillo Point, where temperatures averaged 2-3°C more than at the exposed upwelling sites outside and the bay. Temporal and spatial patterns in sea surface temperature were determined and showed being well associated with wind variability, indicated by the significant correlation between the first empirical orthogonal function modes of temperature variability and wind forcing. We discuss how the persistence of this warm feature and the thermal gradients or frontal structures associated with it are likely to play an important role in retaining larvae or other planktonic organisms in the bay. [ABSTRACT FROM AUTHOR]

In recent years, advances in analyses of the sperm morphology and genetics of Perumytilus purpuratus have allowed to two evolutionary scenarios for this mussel to be suggested: (1) the scenario of cryptic species and (2) the scenario of incipient or in progress speciation. For a better understanding of the evolutionary history of P. purpuratus , we performed extensive sampling along a latitudinal gradient of ca. 7180 km of coastline-from the Southern Pacific Ocean to the Atlantic Ocean-and we delved deeper into the sperm morphology of P. purpuratus , exploring its association with the phylogeny and population genetics to determine whether the variability in sperm traits between the northern and southern regions was a signal of cryptic or incipient species. Overall, our results showed that sperm sizes were strongly correlated with the genetic structure in males of P. purpuratus . We identified at 37° S on the Pacific coast a coincident break of both sperm size and genetic disruption that can be explained by historical events and postglacial recolonization as causal phenomena for the observed divergences. Furthermore, evidence of genetic admixture between lineages was found at 38° S, suggesting the presence of an introgressive hybridization zone and incomplete reproductive isolation in an in fraganti or incipient speciation process.

Objective: The aim of this study was to evaluate the impact on perinatal outcomes related to placental insufficiency with the application of the new 2017 ACC/AHA guidelines to a group of chronic hypertensive pregnancies during their first-trimester assessment., Study Design: This retrospective cohort study included pregnancies with preconceptional hypertension and known perinatal outcomes. In the first trimester, a combined screening for preterm preeclampsia (p-PE) was performed, including blood pressure (BP), mean uterine artery Doppler, and maternal characteristics. Patients were divided, according to the 2017 ACC/AHA consensus, into the following groups: elevated or less, Stage 1, and Stage 2. For adverse perinatal outcome assessment, univariate and multivariate regression analyses were performed, considering the "elevated or less" group as a reference. Odds ratios (OR) were compared with linear trend analysis. The main outcomes measured were preterm PE and FGR < 3 rd percentile., Results: Of the 130 included patients, 59 (45.4%) were classified as elevated or less, 47 (36.2%) as Stage 1, and 24 (18.4%) as Stage 2. p-PE showed a significant increase according to BP range [7% (OR = 1.0), 19.6% (OR = 3.2), and 21.7% (OR = 3.7)]; trend p = 0.02, for elevated or less, Stage 1, and Stage 2, respectively. There was a non-significant increased trend of FGR < 3 rd percentile according to the BP stage. The best multivariate predictive model for p-PE included a previous PE background (OR = 15) and mean arterial pressure in mmHg (OR = 1.1)., Conclusion: The use of the 2017 ACC/AHA consensus in pregnancies with chronic hypertension identifies an intermediate risk group for placental-mediated diseases., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sepúlveda-Martínez, Conrads, Guiñez, Guiñez, Llancaqueo and Parra-Cordero.)

Perumytilus purpuratus is a marine mussel considered a bioengineer species with a broad distribution in the Pacific and Atlantic coast of South America. Studies have shown two geographically and genetically differentiated subpopulations at molecular level and in sperm morphological traits. To open avenues for molecular research on P. purpuratus , a global de novo transcriptome from gonadal tissue of mature males was sequenced using the Illumina platform. From a total of 126.38 million reads, 37,765 transcripts were successfully annotated. BUSCO analysis determined a level of 89% completeness for the assembled transcriptome. The functional gene ontology (GO) annotation indicated that, in terms of abundance, the transcripts related with molecular function were the most represented, followed by those related with biological process and cellular components. Additionally, a subset of GO annotations generated using the "sperm" term resulted in a total of 1,294 sequences where the biological process category was the more represented, with transcripts strongly associated to sperm-processes required for fertilization, and with processes where the sperm-egg interaction could be implicated. Our work will contribute to the evolutionary understanding of the molecular mechanisms related to tissue-specific functions. This work reports the first male gonad transcriptome for the mussel P. purpuratus , generating a useful transcriptomic resource for this species and other closely related mytilids., Competing Interests: Competing Interests: The authors have declared that no competing interest exists.

Tropical parasitic diseases, especially those produced by protozoan parasites, are a major public health problem in many countries, and their impact in the health burden is significant. Oxidative processes proved to be related to these diseases, being the antioxidant agents promising therapeutic solutions for them. Therefore, this review provides an overview of published manuscripts regarding both activities. In particular, the interest of the coumarin derivatives as antioxidant agents with application in parasitic diseases is discussed in this manuscript. The recent findings in this field are highlighted.

At broad geographical scales, the variation in bivalve shell thickness can be modulated by environmental factors that vary with latitude, such as sea surface temperature (SST), seawater pH, or calcium carbonate availability. Mussels usually form multilayered beds, and shell thickness is also expected to be affected by density and layering due to intraspecific competition. In this work, we explored the geographical variation of shell thickness in the intertidal mussel Perumytilus purpuratus between 18° and 42°S along the southeastern Pacific coast. We tested the hypothesis that there was a positive relationship between shell thickness and SST, and then we explored other variables that could have an effect on thickness, such as density, number of layers, and others environmental variables (pH and calcite concentration). The expected positive linear relationship between shell thickness and sea surface temperature was not found, but when the other population variables were included in the analysis, an unexpected inverse SST-thickness relationships appeared as significant, probably because this species could be adapted to colder and more acid seawater as are those of the tips of South America. Thickness was also negatively affected by density, which was expected for a gregarious species showing high intraspecific competition. Finally, our results highlight the importance of including density and crowding effects when macroscale patterns are explored, particularly in gregarious species, since these patterns could also be modulated by density-dependent processes, which might then override latitudinal trends of shell thickness when they are not included in the analyses., (© 2014 Marine Biological Laboratory.)

Invasion by marine nonindigenous species (NIS) is a spread phenomenon. The tunicate Pyura praeputialis shows pronounced disjoint geographical distribution: along thousands of kilometers in wave-swept headlands on the southeastern coast of Australia, from where it appears to have originated, and exclusively along 60-70 km inside the Bay of Antofagasta, Chile. mtDNA sequences suggested that the species invaded this rocky shore recently. We used field manipulations and juvenile P. praeputialis transplant techniques to test hypotheses regarding the capacity of the tunicate to survive and grow at different sites and tidal heights inside and outside Antofagasta, and its competitive performance for primary space (inside the Bay) against the native mussel Perumytilus purpuratus. We conclude that survival and growth of P. praeputialis showed no significant differences among sites inside and outside the Bay, and suggest that the restrictive distribution of the species in Chile is caused by a specific oceanographic retention mechanism and/or its brief larval dispersal. We demonstrated that, inside the Bay, P. praeputialis outcompetes Perumytilus from the Mid-Low intertidal, constraining Perumytilus to the Upper Mid-Intertidal, modifying the local pattern of intertidal zonation. We show that predation on P. praeputialis juveniles by starfish and snails constitutes a regulatory mechanism for the setting of its low intertidal limit. Major ecological impacts caused by NIS invasions to rocky shores by aggressive primary space users may result in negative aspects, but also may contribute to biodiversity enhancement. We call attention to the need for increment manipulations and testing of ecological hypotheses regarding marine NIS.

Intertidal mussels usually form complex multilayered matrices with density-dependent effects on survival and growth, and self-thinning scaling between biomass (B) and density (N) is expected. This article develops a tridimensional model of space-driven self-thinning that in addition to B-N explicitly includes the degree of packing of the mussels, measured as the number of layers (L). The structure of our model (B-N-L) encompasses previous bidimensional models (B-N) of self-thinning as special cases and enables comparisons between mono- and multilayered populations. We contrast the predictions of the bi- and tridimensional models using data obtained from Perumytilus purpuratus mussel beds on the rocky shores of central Chile monitored during a 28-mo period. The tridimensional model suggests that density dependence is much more frequent than hitherto indicated by bidimensional models. We propose that our space-driven tridimensional model may be applied not only to mussels but also to other species where spatial overlapping configurations occur.