Giant viruses inhibit superinfection by downregulating phagocytosis in Acanthamoeba.

In the context of the virosphere, viral particles can compete for host cells. In this scenario, some viruses block the entry of exogenous virions upon infecting a cell, a phenomenon known as superinfection inhibition. The molecular mechanisms associated with superinfection inhibition vary depending on the viral species and the host, but generally, blocking superinfection ensures the genetic supremacy of the virus's progeny that first infects the cell. Giant amoeba-infecting viruses have attracted the scientific community's attention due to the complexity of their particles and genomes. However, there are no studies on the occurrence of superinfection and its inhibition induced by giant viruses. This study shows that mimivirus, moumouvirus, and megavirus, exhibit different strategies related to the infection of Acanthamoeba. For the first time, we have reported that mimivirus and moumouvirus induce superinfection inhibition in amoebas. Interestingly, megaviruses do not exhibit this ability, allowing continuous entry of exogenous virions into infected amoebas. Our investigation into the mechanisms behind superinfection blockage reveals that mimivirus and moumouvirus inhibit amoebic phagocytosis, leading to significant changes in the morphology and activity of the host cells. In contrast, megavirus-infected amoebas continue incorporating newly formed virions, negatively affecting the available viral progeny. This effect, however, is reversible with chemical inhibition of phagocytosis. This work contributes to the understanding of superinfection and its inhibition in mimivirus, moumouvirus, and megavirus, demonstrating that despite their evolutionary relatedness, these viruses exhibit profound differences in their interactions with their hosts.IMPORTANCESome viruses block the entry of new virions upon infecting a cell, a phenomenon known as superinfection inhibition. Superinfection inhibition in giant viruses has yet to be studied. This study reveals that even closely related viruses, such as mimivirus, moumouvirus, and megavirus, have different infection strategies for Acanthamoeba. For the first time, we have reported that mimivirus and moumouvirus induce superinfection inhibition in amoebas. In contrast, megaviruses do not exhibit this ability, allowing continuous entry of exogenous virions into infected amoebas. Our investigation shows that mimivirus and moumouvirus inhibit amoebic phagocytosis, causing significant changes in host cell morphology and activity. Megavirus-infected amoebas, however, continue incorporating newly formed viruses, affecting viral progeny. This research enhances our understanding of superinfection inhibition in these viruses, highlighting their differences in host interactions.

Fuzzy and spatial analysis of cutaneous leishmaniasis in Pará State, Brazilian Amazon: an ecological and exploratory study.

INTRODUCTION: This study sought to analyze the relationships between cutaneous leishmaniasis and its epidemiological, environmental and socioeconomic conditions, in the 22 microregions of Pará state, Brazil, for the period from 2017 to 2022. METHODOLOGY: In this ecological and exploratory study, the microregions were used as spatial units because they are formed by contiguous municipalities with similar characteristics. The epidemiological, environmental, socioeconomic, and public health policy data employed were obtained from the official information systems at the Ministry of Health, National Institute for Space Research, and Brazilian Institute of Geography and Statistics. A fuzzy system was developed to identify risk factors for the disease, using Python programming language. The results were analyzed with the bivariate Global Moran spatial analysis technique. RESULTS: It was observed that the Altamira microregion had the highest risk percentage for the disease, while Breves had the lowest, with significant differences in the relevance of its conditioning factors, mainly related to land use and cover patterns, in addition to demography and living conditions index, education and public health policies. CONCLUSIONS: The fuzzy system associated with the geostatistical technique was satisfactory for identifying areas with health vulnerability gradients related to deforestation, pasture, poverty, illiteracy, and health services coverage, as its conditioning variables. Thus, it was demonstrated that deforestation was the main risk factor for the disease. The system can also be used in environmental and epidemiological surveillance.

Assessing the Risk Stratification of Breast Cancer Polygenic Risk Scores in a Brazilian Cohort.

Polygenic risk scores (PRSs) for breast cancer have a clear clinical utility in risk prediction. PRS transferability across populations and ancestry groups is hampered by population-specific factors, ultimately leading to differences in variant effects, such as linkage disequilibrium and differences in variant frequency (allele frequency differences). Thus, locally sourced population-based phenotypic and genomic data sets are essential to assess the validity of PRSs derived from signals detected across populations. This study assesses the transferability of a breast cancer PRS composed of 313 risk variants (313-PRS) in a Brazilian trihybrid admixed ancestries (European, African, and Native American) whole-genome sequenced cohort, the Rare Genomes Project. 313-PRS was computed in the Rare Genomes Project (n = 853) using the UK Biobank (UKBB; n = 264,307) as reference. The Brazilian cohorts have a high European ancestry (EA) component, with allele frequency differences and to a lesser extent linkage disequilibrium patterns similar to those found in EA populations. The 313-PRS distribution was found to be inflated when compared with that of the UKBB, leading to potential overestimation of PRS-based risk if EA is taken as a standard. However, case controls lead to equivalent predictive power when compared with UKBB-EA samples with area under the receiver operating characteristic curve values of 0.66 to 0.62 compared with 0.63 for UKBB.

Effect of different levels of whole corn germ on energy values and ileal digestibility in broilers.

This study evaluated the effects of broiler age (A) and levels of replacement (L) of control diet (CD) on the utilization of energy and nutrients of whole corn germ. 720 one-day-old broilers (b) were allocated at completely randomized design to six treatments and six replicates, in three assays: pre-starter (1-8 days, 10 b/cage), starter (15-22 days, 6 b/cage), and grower (28-35 days, 4 b/cage) phases. The treatments were: CD and four test diets (L): 100, 150, 200, 250, or 300 g kg-1 of the CD replaced by WCG levels. The data were adjusted to the response surface model. The stationary points for apparent energy metabolizable (AME) and AME corrected for nitrogen balance (AMEn) were: 4173 and 3591 kcal kg-1, respectively, and coefficients of gross energy (AMCGE), crude protein (AMCCP), dry matter (AMCDM), and ether extract (AMCEE) were: 49.3, 40.4, 72.6, and 61.3%, respectively; and Ileal digestibility coefficient of crude protein (IDCCP), dry matter (IDCDM), digestibility crude protein values (DCP), and digestibility dry matter value (DDM) were: 78.0, 57.96, 8.50, and 56.17%, respectively. The EP for AMEn was at 18 days of age, 28 g kg-1 WCG. There was a correlation between A and L on digestibility and metabolisability of nutrient's WCG.

Protein supplementation during mid-gestation affects maternal voluntary feed intake, performance, digestibility, and uterine blood flow of beef cows.

This study aimed to assess the impact of protein supplementation and its interaction with calf sex (CS) on the performance, metabolism and physiology of pregnant beef cows. Fifty-two multiparous Zebu beef cows carrying female (n = 22) and male (n = 30) fetuses were used. Cows were individually housed from day 100 to 200 of gestation and randomly assigned to restricted (RES, n = 26) or supplemented (SUP, n = 26) groups. The RES cows were ad libitum fed a basal diet (corn silage + sugarcane bagasse + mineral mixture), achieving 5.5% crude protein (CP), while SUP cows received the same basal diet plus a protein supplement (40% CP, at 3.5 g/kg of body weight). All cows were fed the same diet during late gestation. Differences were declared at p < 0.05. No significant interaction between maternal nutrition and calf sex was found for maternal outcomes (p ≥ 0.34). The SUP treatment increased the total dry matter (DM) intake (p ≤ 0.01) by 32% and 19% at mid- and late-gestation respectively. The total tract digestibility of all diet components was improved by SUP treatment at day 200 of gestation (p ≤ 0.02), as well as the ruminal microbial CP production (p ≤ 0.01). The SUP treatment increased (p ≤ 0.03) the cows' body score condition, ribeye area, the average daily gain (ADG) of pregnant components (PREG; i.e., weight accretion of cows caused by pregnancy) and the ADG of maternal tissues (i.e., weight accretion discounting the gain related to gestation) in the mid-gestation. The SUP cows exhibited a lower maternal ADG (p < 0.01) compared to RES cows in late pregnancy. There was a 24% additional gain (p < 0.01) in the PREG components for SUP cows during late gestation, which in turn improved the calf birthweight (p = 0.05). The uterine arterial resistance and pulsatility indexes (p ≤ 0.01) at mid-gestation were greater for RES cows. In conclusion, protein supplementation during mid-gestation is an effective practice for improving maternal performance, growth of the gravid uterus and the offspring's birth weight.

Partial amputation due to tongue bite in death-associated with eclampsia.

Eclampsia is one of the most dangerous complications of pregnancy and has a high incidence in developing countries. It is characterized by coma and the occurrence of generalized tonic-clonic seizures in pregnant women with hypertension. Deep bites on the tongue and other orofacial injuries have been described as consequences of these seizures. We present a case of death associated with eclampsia in which the bite during the seizure episode caused almost total amputation of an enlarged tongue (macroglossia). The medico-legal value of this finding and the situation due to antecedent pathological conditions and lack of routine screening in pregnant women who may migrate legally or illegally to give birth with better medical care are discussed.

Digital matching of palatal rugae patterns for forensic identification in edentulous denture wearers.

Identifying edentulous victims in forensic contexts poses a significant challenge. It has been reported that having a denture to reproduce and compare Palatal Rugae (PR) patterns is crucial for identifying edentulous individuals, yet there are no validated protocols for conducting this procedure. In this study, a new method was developed and validated for plaster molding of the internal surface of upper dentures, along with a protocol involving focus-stacked photographs and reference scales. Thirty-eight edentulous subjects participated in the study, obtaining plaster models of the patients (PM), and their dentures (AM) were standardized. The AM/PM model was highlighted and photographed with ten shots in different z-focuses for each model, using standard lighting and aligning the position of the PR perpendicular to the photographic axis using tubular spirit levels and modeling clay. The images were processed using the stacking technique and analyzed by three observers through the proposed protocol using Adobe® Photoshop®. The results were analyzed based on the intra-observer and inter-observer agreement levels, with a 95% confidence interval. This study demonstrated high-precision intra-observer and inter-observer agreement (k = 1) in the matching of Palatal Rugae (PR) and maxillary morphology obtained from participants and their dentures. The protocol is simple, cost-effective, and precise. It enables standardization of the technique for obtaining plaster models, and the exposure of PR and photographic protocol minimizes the presence of artifacts in the images, thereby reducing the likelihood of errors and promoting the reproducibility of both the recording technique and the comparison of the PR.

The Malaria Box molecules: a source for targeting the RBD and NTD cryptic pocket of the spike glycoprotein in SARS-CoV-2.

CONTEXT: SARS-CoV-2, responsible for COVID-19, has led to over 500 million infections and more than 6 million deaths globally. There have been limited effective treatments available. The study aims to find a drug that can prevent the virus from entering host cells by targeting specific sites on the virus's spike protein. METHOD: We examined 13,397 compounds from the Malaria Box library against two specific sites on the spike protein: the receptor-binding domain (RBD) and a predicted cryptic pocket. Using virtual screening, molecular docking, molecular dynamics, and MMPBSA techniques, they evaluated the stability of two compounds. TCMDC-124223 showed high stability and binding energy in the RBD, while TCMDC-133766 had better binding energy in the cryptic pocket. The study also identified that the interacting residues are conserved, which is crucial for addressing various virus variants. The findings provide insights into the potential of small molecules as drugs against the spike protein.

Study of Lip Conditions Associated with Lip Print Patterns: A New Perspective on Cheiloscopy / Estudio de Afecciones Labiales Asociadas a sus Patrones de Huellas: Una Nueva Perspectiva en Queiloscopía

SUMMARY: Although almost all studies exclude lip conditions because they would affect furrow patterns, some authors maintain that they should be considered temporary or permanent disabilities, all of which require further research in this context.We present a study in which we associate lip conditions with lip print patterns to associate both morphological elements for fieldwork purposes. Fifty-seven women and 48 men aged between 19 and 38 years who resided in Temuco (Chile) were included. The lip conditions and their prints were recorded, and an analysis, comparison, evaluation, and verification protocol (ACE-V) for lip prints was applied. Of the participants, 27.4 % had healthy lips, while 71.7 % had some type of condition. Although patterns related to temporary and permanent lip conditions were recognized in the lip prints in a non-significant way, the diagnosis of "healthy" or "altered" lip status could be made significantly by a calibrated examiner. Although these conditions do not represent identifying variables without empirical studies to validate them, they can affect the quality of the evaluated lip print; therefore, they should be recognized during the analyses considering the prevalence of these conditions.

Aunque casi todos los estudios excluyen las afecciones labiales pues afectarían los patrones de sus surcos y huellas, algunos autores sostienen que deben ser consideradas alteraciones temporales o permanentes, por lo que se requiere mayor investigación en este aspecto. Se presenta un estudio en el que se asocian afecciones labiales con sus patrones de huellas para evaluar conjuntamente ambos elementos morfológicos con fines de trabajo forense de campo. Se incluyeron 57 mujeres y 48 hombres con edades entre 19 y 38 años residentes en Temuco (Chile). Se registraron las afecciones de los labios y sus huellas, y se aplicó un protocolo de análisis, comparación, evaluación y verificación (ACE-V) para las huellas labiales. De los participantes, el 27,4 % tenía labios sanos, mientras que el 71,7 % presentaba algún tipo de afección. Aunque los patrones relacionados con afecciones labiales temporales y permanentes se reconocieron en las huellas labiales de manera no significativa, un examinador calibrado podría realizar significativamente el diagnóstico de estado labial "sano" o "alterado". Si bien estas condiciones no representan variables de identificación sin estudios empíricos que las validen, pueden afectar la calidad de la impresión labial evaluada; por lo tanto, deben ser reconocidos durante los análisis considerando la prevalencia de estas condiciones.

Application of ecotoxicological tools to evaluate the quality status of mangroves under restoration in the Yucatán Peninsula, Mexico.

Ecotoxicological tools, namely biomarkers and bioassays, may provide insights on the ecological quality status of mangroves under restoration. We investigated how 1) physicochemical parameters and water bioassays using Artemia franciscana; and 2) quantification of sublethal (osmoregulatory capacity, biochemical, and oxidative stress) and individual biomarkers (density, length-weight relationship [LWR], parasitic prevalence) in the sentinel fiddler crab Minuca rapax, can improve restoration indicators in mangroves from the Yucatán Peninsula, Southern Gulf of Mexico. We showed that water quality was improved with restoration, but still presented toxicity. Regarding sublethal biomarkers, M rapax from restored areas lower osmotic regulatory capacity, higher oxidative stress, and showed lipid peroxidation. As to the individual biomarkers, the density, LWR, and the prevalence of parasites in M. rapax was higher in restored areas. The use of bioassays/biomarkers were useful as early warning indicators to better assess the health of mangroves under restoration.

Comparison of arterial hypotension incidence during general anesthesia induction - target-controlled infusion vs. bolus injection of propofol: a randomized clinical trial.

BACKGROUND: The incidence of arterial hypotension during induction of general anesthesia is influenced by the method of propofol administration, but there is a dearth of randomized clinical trials comparing bolus injection and target-controlled infusion in relation to arterial hypotension. This study seeks to compare the incidence of arterial hypotension between these two methods of propofol administration. METHODS: This prospective, randomized, single-center, non-blinded study included 60 patients (aged 35 to 55 years), classified as ASA physical status I or II, who were undergoing non-cardiac surgeries. They were randomly allocated using a computer to two groups based on the method of propofol administration during the induction of general anesthesia: the Target Group, receiving target-controlled infusion at 4 µg.mL-1, and the Bolus Group, receiving a bolus infusion of 2 mg.kg-1. Both groups also received midazolam 2 mg, fentanyl 3 µg.kg-1, and rocuronium 0.6 mg.kg-1. Over the first 10 minutes of anesthesia induction, Mean Arterial Pressure (MAP), Heart Rate (HR), level of Consciousness (qCON), and Suppression Rate (SR) were recorded every 2 minutes. RESULTS: Twenty-seven patients remained in the TCI group, while 28 were in the Bolus group. Repeated measure analysis using mixed-effects models could not reject the null hypothesis for the effect of group-time interactions in MAP (p = 0.85), HR (p = 0.49), SR (p = 0.44), or qCON (p = 0.72). The difference in means for qCON (60.2 for TCI, 50.5 for bolus, p < 0.001), MAP (90.3 for TCI, 86.2 for bolus, p < 0.006), HR (76.2 for TCI, 76.9 for bolus, p = 0.93), and SR (0.01 for TCI, 5.5 for bolus, p < 0.001), irrespective of time (whole period means), revealed some significant differences. CONCLUSION: Patients who received propofol bolus injection exhibited a lower mean arterial pressure, a greater variation in the level of consciousness, and a higher suppression rate compared to those who received it as a target-controlled infusion. However, the interaction effect between groups and time remains inconclusive.

Maternal and neonatal effects of epidural levobupivacaine combined with fentanyl or sufentanil for elective cesarean-section in brachycephalic breeds.

The aim of this study was to compare the safety and clinical efficacy of epidural levobupivacaine combined with fentanyl or sufentanil for bitches undergoing elective cesarean-section and the impact of these anesthetic protocols on neonatal viability. The anesthetic protocol consisted of intramuscular morphine (0.2 mg/kg), followed by an intravenous bolus of propofol, in a dose sufficient to allowed the puncture of the lumbosacral space. The dogs were randomly allocated to receive 0.5 % levobupivacaine plus fentanyl (2.5 µg/kg; LF: n = 9) or sufentanil (1 µg/kg; LS; n = 11). Maternal cardiorespiratory parameters were monitored at specific time points during surgery. Intraoperative propofol supplementation was based on the presence of head and/or thoracic limb movements. Neonatal reflex responses and the Apgar score (range 0-10 points) were assessed at 5 and 60 minutes after birth. Puppy mortality rate was recorded until 24 hours after birth. Data were analyzed using two-way ANOVA, Tukey's test, Wilcoxon signed rank test, and Fisher's exact test (P < 0.05). Intraoperatively, maternal cardiorespiratory variables and propofol requirements were similar between groups, with no detection of anesthetic complications. The puppy reflex responses did not differ between groups at any time point. The medians (range) of Apgar scores were lower (P = 0.016) in the LF [5 (1-9)] at 5 minutes in comparison with LS [6 (2-9)], while no intergroup differences were recorded at 60 minutes [LF = 8 (2-10); LS = 9 (6-10]. The total mortality rate was 4.1 %. In the LS group, no puppies died, while in the LF 8 % of the puppies died in the first 24 hours after birth (P = 0.11). Epidural levobupivacaine combined with fentanyl or sufentanil provided minimal maternal and neonatal adverse effects, but neither protocol enabled the performance of a C-section in 100 % of the French and English bulldogs, without propofol supplementation.

Feces and molting as microplastic sinks in a mangrove crab.

We exposed adult individuals of the sentinel mangrove crab Minuca rapax to waterborne microplastics (MP; 53-63 µm polyethylene spheres) in a long-term experiment (56 days). Weassessed 1) MP effects on growth, survival, and food intake. and 2) the MP tissue acumulation and its reduction of body burden through feces and molting. MP exposure did not affect growth and survival. The hepatopancreas accumulated more MP than the gills and muscle. Most of the ingested MP particles were released in the feces and molts, indicating a rapid passage through the digestive tract. MP impaired food intake of M. rapax, with unknown consequences to the local populations. These results provide insights on MP translocation mechanisms, its elimination and toxicity associated with MP.

A novel conservative technique to allow oral opening and overcome rigor mortis during medicolegal autopsy.

This study presents a novel conservative technique to increase oral opening and overcome rigor mortis during medicolegal autopsy (MLA). The method proposes a myotomy of the temporalis and masseter muscles, taking advantage of the incisions of the cranial opening procedures, to achieve a significant oral opening (≥ 30 mm) in fresh cadavers with established rigor mortis without altering facial aesthetics. The study was performed on 48 individuals aged between 18 and 66 years (20 males and 28 females) who were autopsied at the Instituto Nacional de Patología Forense Dr. Sergio Sarita Valdez (Santo Domingo, Dominican Republic). The proposed technique not only allowed the oral access to all autopsied cadavers but also complied with current ethical standards for preserving facial aesthetics, taking into account the concerns of family members by allowing respectful viewing of the cadaver. This advancement not only contributes to the efficiency of oral autopsies but also influences public perception of forensic procedures and highlights the importance of ethical and aesthetic considerations in the context of MLAs. The proposed technique represents a significant step towards more respectful and ethical forensic practices, and offers practical advantages for a more complete and accurate assessment during MLA.

Dental Loss in the Lower Socioeconomic Stratum of a Sample of the Chilean Population Born in the 19TH and 20TH Centuries / Pérdida Dental en el Estrato Socioeconómico Bajo de una Muestra de la Población Chilena Nacida en los Siglos XIX y XX

SUMMARY: Partial or total dental loss (edentulism) is associated with decreased quality of life. Chile has large socioeconomic gaps, which are also recognized in oral health, but it is not known how Edentulism has evolved throughout the country. The aim of this study was to determine the edentulism in people born during the 19th and 20th centuries in Chile, who died in the 20th century, and to compare it with current data from the Chilean Ministry of Health (MINSAL) to observe its evolution in the country. For this purpose, 60 3D models of skulls from the Subactual Osteological Collection of Santiago were analyzed (30 individuals per sex), in which the presence and absence of teeth in antemortem in the maxilla were analyzed. A high percentage of tooth loss was observed, with 65 % partial edentulism, a 30 % total edentulism, and only 5 % had complete dentition in this osteological collection. In addition, a significant decrease over time was found; in 2017, the percentage of complete dentition at the national level was 32.8 %. A higher frequency of edentulism was also found in females from the osteological collection, with a significant probability of twice as much edentulism as in males. However, this sex difference was smaller than those found in the current study. Our study is the first to compare edentulism in Chile in two different time periods, since, in addition to studying it in the 19th and 20th century, it is carried out with data from the present day and in line with previous research, reveals the importance of socioeconomic and sex variables for dental loss.

La pérdida parcial o total de dientes (edentulismo) se asocia a una disminución de la calidad de vida. Chile tiene grandes brechas socioeconómicas, que también se reconocen en la salud oral, pero se desconoce cómo ha evolucionado el edentulismo en el país. El objetivo de este estudio fue determinar el edentulismo en personas nacidas durante los siglos XIX y XX en Chile y fallecidas en el siglo XX, y compararlo con datos actuales del Ministerio de Salud de Chile (MINSAL) para observar su evolución en el país. Para ello, se analizaron 60 modelos 3D de cráneos de la Colección Osteológica Subactual de Santiago (30 individuos por sexo), en los que se analizó la presencia y ausencia de dientes en dentición antemortem en el maxilar. Se observó un alto porcentaje de pérdida dentaria, con un 65 % de edentulismo parcial y un 30 % de edentulismo total, y sólo un 5 % presentaba dentición completa en esta colección osteológica. Además, se encontró una disminución significativa a lo largo del tiempo; en 2017, la dentición completa a nivel país fue del 32,8 %. También se encontró una mayor frecuencia de edentulismo en las mujeres de la colección osteológica, con una probabilidad significativa del doble de edentulismo que en los hombres. Sin embargo, esta diferencia de sexo fue menor que la hallada en datos actuales. Este estudio es el primero que compara el edentulismo en Chile en dos épocas diferentes, ya que además de estudiarlo en los siglos XIX y XX, se realizó con datos de la actualidad y, en línea con investigaciones previas, revela la importancia de las variables socioeconómicas y de sexo en la pérdida dental.

An R Script to Estimate Which and How Many Landmarks Represent the Most Variable Parts of an Object / Un Script R para Estimar Cuáles y Cuántos Puntos de Referencia Representan las Partes más Variables de un Objeto

SUMMARY: The study of the shape variation in geometric morphometrics has an important limitation known as the Pinocchio effect. The Pinocchio effect produces artifactual variances of the landmarks and implies that it is not possible to know the morphological change structure of an object, other than by dividing the landmark sets and then comparing them. This, however, involves making prior assumptions about the pattern of variation of an object. In this study, we provide a code in R to iterate over a complete set of landmarks and test all possible combinations of landmarks until deliver those landmarks associated with the largest to the smallest morphological changes. We tested this on a sample of 28 landmarks in 143 3D models of human skulls. The results indicated that this process can result in a pooled variance of a subset of landmarks that is an order of magnitude larger than that of several other regions of the skull. This method makes it possible to describe the pattern of variation of any 2D or 3D object represented by fixed landmarks, to distinguish the shape features that have more morphological dispersion, and to avoid any aprioristic assumptions about how the morphological changes of an object behave.

El estudio de la variación de la forma en morfometría geométrica tiene una limitación importante conocida como efecto Pinocho. El efecto Pinocho produce variaciones artefactos de los puntos de referencia e implica que no es posible conocer la estructura del cambio morfológico de un objeto, salvo dividiendo los conjuntos de puntos de referencia y luego comparándolos. Sin embargo, esto implica hacer suposiciones previas sobre el patrón de variación de un objeto. En este estudio, proporcionamos un código en R para iterar sobre un conjunto completo de puntos de referencia y probar todas las combinaciones posibles de puntos de referencia hasta entregar aquellos puntos de referencia asociados con los cambios morfológicos más grandes a los más pequeños. Probamos esto en una muestra de 28 puntos de referencia en 143 modelos 3D de cráneos humanos. Los resultados indicaron que este proceso puede dar como resultado una variación combinada de un subconjunto de puntos de referencia que es un orden de magnitud mayor que el de varias otras regiones del cráneo. Este método permite describir el patrón de variación de cualquier objeto 2D o 3D representado por puntos de referencia fijos, distinguir las características de forma que tienen más dispersión morfológica y evitar suposiciones apriorísticas sobre cómo se comportan los cambios morfológicos de un objeto.

Influences of sociality and maternal size on reproductive strategies: trade-offs between offspring size and quantity in five Anelosimus species (Araneae, Theridiidae).

Individuals can experience accentuated disputes for resources when living with many conspecifics, even in situations in which cooperative behaviors assure benefits associated with an increase in the frequency of food acquisition and in diet breadth. Thus, intraspecific competition may exert a significant selective pressure on social animals. Theoretical models suggest that females of social species could improve their fitness by producing relatively large offspring, since body size can provide competitive advantages during foraging activities. As female reserves are limited, the production of large offspring would occur at the expense of their number. Using five Anelosimus (Araneae, Theridiidae) species, we assessed whether the social ones produce fewer and larger eggs than the subsocials. In addition, we tested the effect of female size on the adoption of each particular reproductive strategy. Small females could hypothetically invest in producing large offspring since they cannot produce as many offspring as large females. Our results suggested that, indeed, sociality influences reproductive strategies. Females of social species produced fewer and larger offspring than females of subsocial species. Subsociality, in turn, would benefit the production of many small spiderlings, possibly because a large number of siblings is important to maintain and expand new webs and to subdue prey during their initial instars. Our results also indicated that large females produce more eggs without necessarily reduce their sizes. We discussed how the costs and benefits of group living may influence reproductive strategies.

Tolerance and behavioral responses of crabs in disturbed mangroves during a heatwave event.

We assessed the tolerance, safety margins, and behavioral responses to extreme conditions of the mangrove fiddler crab Leptuca speciosa during a heatwave event (May of 2022), in the Yucatán Peninsula, Mexico. In the field, L. speciosa demonstrated aggregation behavior, congregating in areas that were above the water level to escape the extreme water conditions. In the laboratory, we determined that the upper critical thermal limits (UT99) ranged from 40.2 °C and 42 °C. For salinity, the lethal concentration was LC99 = 39 psu. Our study showed that L. speciosa, one of the most conspicuous and resilient inhabitants of mangroves, had no safety margin and low tolerance to the climatic conditions as measured in the heatwave, and displayed a protective behavior. Considering that the frequency and intensity of heatwaves have been predicted to increase in the next few years, the combined multiple stressors effect may increase the vulnerability of mangrove organisms.

Influence of leptin and its receptors on individuals under chronic social stress behavior.

Stress is the body's physiological reaction to a dangerous or threatening situation, leading to a state of alertness. This reaction is necessary for developing an effective adaptive response to stress and maintaining the body's homeostasis. Chronic stress, caused mainly by social stress, is what primarily affects the world's population. In the last decades, the emergence of psychological disorders in humans has become more frequent, and one of the symptoms that can be observed is aggressiveness. In the brain, stress can cause neuronal circuit alterations related to the action of hormones in the central nervous system. Leptin, for example, is a hormone capable of acting in brain regions and neuronal circuits important for behavioral and emotional regulation. This study investigated the correlation between chronic social stress, neuroendocrine disorders, and individual behavioral changes. Then, leptin and its receptors' anatomical distribution were evaluated in the brains of mice subjected to a protocol of chronic social stress. The model of spontaneous aggression (MSA) is based on grouping young mice and posterior regrouping of the same animals as adults. According to the regrouping social stress, we categorized the mice into i) harmonic, ii) attacked, and iii) aggressive animals. For leptin hormone evaluation, we quantified plasma and brain concentrations by ELISA and evaluated its receptor and isoform expression by western blotting. Moreover, we verified whether stress or changes in leptin levels interfered with the animal's body weight. Only attacked animals showed reduced plasma leptin concentration and weight gain, besides a higher expression of the high-molecular-weight leptin receptor in the amygdala and the low-molecular-weight receptor in the hippocampal region. Aggressive animals showed a reduction in the cerebral concentration of leptin in the hippocampus and a reduced high-and low-molecular-weight leptin receptor expression in the amygdala. The harmonic animals showed a reduction in the cerebral concentration of leptin in the pituitary and a reduced expression of the high-molecular-weight leptin receptor in the amygdala. We then suggest that leptin and its receptors' expression in plasma and specific brain areas are involved in how individuals react in stressful situations, such as regrouping stress in MSA.