Incidence of intra-abdominal injuries in hemodynamically stable blunt trauma patients with a normal computed tomography scan admitted to the emergency department.

OBJECTIVES: Blunt abdominal trauma is a common cause of emergency department admission. Computed tomography (CT) scanning is the gold standard method for identifying intra-abdominal injuries in patients experiencing blunt trauma, especially those with high-energy trauma. Although the diagnostic accuracy of this imaging technique is very high, patient admission and prolonged observation protocols are still common practices worldwide. We aimed to evaluate the incidence of intra-abdominal injury in hemodynamically stable patients with high-energy blunt trauma and a normal abdominal CT scan at a Level-1 Trauma Center in Colombia, South America, to assess the relevance of a prolonged observation period. METHODS: We performed a retrospective study of patients admitted to the emergency department for blunt trauma between 2021 and 2022. All consecutive patients with high-energy mechanisms of trauma and a normal CT scan at admission were included. Our primary outcomes were the incidence of intra-abdominal injury identified during a 24-hour observation period or hospital stay, ICU admission, and death. RESULTS: We included 480 patients who met the inclusion criteria. The median age was 33 (IQR 25.5, 47), and 74.2% were male. The most common mechanisms of injury were motor vehicle accidents (64.2%), falls from height (26%), and falls from bikes (3.1%). A total of 99.2% of patients had a Revised Trauma Score of 8. Only 1 patient (0.2%) (95% CI: 0.01-1.16) presented with an abdominal injury during the observation period. No ICU admissions or deaths were reported. CONCLUSION: The incidence of intra-abdominal injury in patients with hemodynamically stable blunt trauma and a negative abdominal CT scan is extremely low, and prolonged observation may not be justified in these patients.

Anti-TGFß (Transforming Growth Factor ß) Therapy With Betaglycan-Derived P144 Peptide Gene Delivery Prevents the Formation of Aortic Aneurysm in a Mouse Model of Marfan Syndrome.

Objective: We investigated the effect of a potent TGFß (transforming growth factor ß) inhibitor peptide (P144) from the betaglycan/TGFß receptor III on aortic aneurysm development in a Marfan syndrome mouse model. Approach and Results: We used a chimeric gene encoding the P144 peptide linked to apolipoprotein A-I via a flexible linker expressed by a hepatotropic adeno-associated vector. Two experimental approaches were performed: (1) a preventive treatment where the vector was injected before the onset of the aortic aneurysm (aged 4 weeks) and followed-up for 4 and 20 weeks and (2) a palliative treatment where the vector was injected once the aneurysm was formed (8 weeks old) and followed-up for 16 weeks. We evaluated the aortic root diameter by echocardiography, the aortic wall architecture and TGFß signaling downstream effector expression of pSMAD2 and pERK1/2 by immunohistomorphometry, and Tgfß1 and Tgfß2 mRNA expression levels by real-time polymerase chain reaction. Marfan syndrome mice subjected to the preventive approach showed no aortic dilation in contrast to untreated Marfan syndrome mice, which at the same end point age already presented the aneurysm. In contrast, the palliative treatment with P144 did not halt aneurysm progression. In all cases, P144 improved elastic fiber morphology and normalized pERK1/2-mediated TGFß signaling. Unlike the palliative treatment, the preventive treatment reduced Tgfß1 and Tgfß2 mRNA levels. Conclusions: P144 prevents the onset of aortic aneurysm but not its progression. Results indicate the importance of reducing the excess of active TGFß signaling during the early stages of aortic disease progression.

Degree of pectin methyl esterification in endosperm cell walls is involved in embryo bending in Arabidopsis thaliana.

The endosperm is a transitory structure involved in proper embryo elongation. The cell walls of mature seed endosperm are generally composed of a uniform distribution of cellulose, unesterified homogalacturonans, and arabinans. Recent studies suggest that changes in cell wall properties during endosperm development could be related to embryo growth. The degree of methyl esterification of homogalacturonans may be involved in this endosperm tissue remodelling. The relevance of the degree of homogalacturonan methyl esterification during seed development was determined by immunohistochemical analyses using a panel of probes with specificity for homogalaturonans with different degrees of methyl esterification. Low-esterified and un-esterified homogalacturonans were abundant in endosperm cells during embryo bending and were also detected in mature embryos. BIDXII (BDX) could be involved in seed development, because bdx-1 mutants had misshapen embryos. The methyl esterification pattern described for WT seeds was different during bdx-1 seed development; un-esterified homogalacturonans were scarcely present in the cell walls of endosperm in bending embryos and mature seeds. Our results suggested that the degree of methyl esterification of homogalacturonans in the endosperm cell wall may be involved in proper embryo development.

NaStEP: a proteinase inhibitor essential to self-incompatibility and a positive regulator of HT-B stability in Nicotiana alata pollen tubes.

In Solanaceae, the self-incompatibility S-RNase and S-locus F-box interactions define self-pollen recognition and rejection in an S-specific manner. This interaction triggers a cascade of events involving other gene products unlinked to the S-locus that are crucial to the self-incompatibility response. To date, two essential pistil-modifier genes, 120K and High Top-Band (HT-B), have been identified in Nicotiana species. However, biochemistry and genetics indicate that additional modifier genes are required. We recently reported a Kunitz-type proteinase inhibitor, named NaStEP (for Nicotiana alata Stigma-Expressed Protein), that is highly expressed in the stigmas of self-incompatible Nicotiana species. Here, we report the proteinase inhibitor activity of NaStEP. NaStEP is taken up by both compatible and incompatible pollen tubes, but its suppression in Nicotiana spp. transgenic plants disrupts S-specific pollen rejection; therefore, NaStEP is a novel pistil-modifier gene. Furthermore, HT-B levels within the pollen tubes are reduced when NaStEP-suppressed pistils are pollinated with either compatible or incompatible pollen. In wild-type self-incompatible N. alata, in contrast, HT-B degradation occurs preferentially in compatible pollinations. Taken together, these data show that the presence of NaStEP is required for the stability of HT-B inside pollen tubes during the rejection response, but the underlying mechanism is currently unknown.

Pulmonary transit of contrast during exercise is related to improved cardio-pulmonary performance in highly trained endurance athletes.

BACKGROUND: The mechanisms underlying the high interindividual variability demonstrated for right-ventricular (RV) adaptation to exercise have not yet been identified, but different pulmonary vascular adaptations among individuals could be involved. Pulmonary transit of agitated saline (PTAS) during exercise has been demonstrated to be a good estimator of vascular reserve. AIM: The aim of this study was to evaluate the presence of PTAS among endurance athletes (EAs) of both sexes and its influence on RV adaptation to exercise. METHODS: A total of 100 highly trained EAs performed a maximal cardiopulmonary exercise test. Bi-ventricular functional and structural characteristics as well as PTAS were evaluated at baseline and at peak exercise. Athletes were distributed between two groups based on the amount of PTAS during exercise as high (HTPAS; >12 bubbles) and low (LPTAS; ≤12 bubbles). RESULTS: Overall, 11 EAs exhibited an intra-cardiac shunt at rest and 1 met the criteria for chronic pulmonary disease and were excluded from the study. Among the remaining 88 EAs (51% women), 47 (53%) athletes were classified as HPTAS and 41 (47%) as LPTAS. HPTAS capability was associated with significantly larger RV contractile reserve, larger pulmonary vascular reserve and an enhanced maximal exercise capacity. On multivariate analysis, females were the only independent correlate of the HPTAS capability. CONCLUSION: In highly trained endurance athletes, a HPTAS capability during exercise corresponded to an increase in pulmonary vascular and RV contractile reserves as well as an enhanced maximal exercise capacity. The long-term clinical or performance implications of the absence or presence of pulmonary shunting, and the subsequent RV afterload increase while performing exercise, remains to be determined.

The seed water content as a time-independent physiological trait during germination in wild tree species such as Ceiba aesculifolia.

Seeds constitute a key physiological stage in plants life cycle. During seed germination, there is a spatial-temporal imbibition pattern that correlates with described physiological processes. However, only the moment of testa rupture has been described as a critical, discrete stage. Could a specific relative water content (RWC) value reflect a physiological stage useful for comparisons between seed batches? We tracked seed-by-seed imbibition during germination to homogenize sampling and selected a transcriptomic approach to analyse the physiological transitions that occur in seed batches collected in different years and with contrasting phenotypic responses to a priming treatment. The seed RWC reflected the transcriptional transitions that occur during germination, regardless of imbibition time or collection year, and revealed a set of biological processes that occur in the dry seed and during early germination are associated with the phenotypic response to priming. As climate shifts, so do the timing of developmental events important for determining organismal fitness, and poses another challenge to the comprehension of molecular and physiological processes driving the interaction between organisms and environment. In this study, we demonstrate that the use of physiological traits, specific to a particular developmental stage, is a reliable time-independent approach.

Pollination in Nicotiana alata stimulates synthesis and transfer to the stigmatic surface of NaStEP, a vacuolar Kunitz proteinase inhibitor homologue.

After landing on a wet stigma, pollen grains hydrate and germination generally occurs. However, there is no certainty of the pollen tube growth through the style to reach the ovary. The pistil is a gatekeeper that evolved in many species to recognize and reject the self-pollen, avoiding endogamy and encouraging cross-pollination. However, recognition is a complex process, and specific factors are needed. Here the isolation and characterization of a stigma-specific protein from N. alata, NaStEP (N. alata Stigma Expressed Protein), that is homologous to Kunitz-type proteinase inhibitors, are reported. Activity gel assays showed that NaStEP is not a functional serine proteinase inhibitor. Immunohistochemical and protein blot analyses revealed that NaStEP is detectable in stigmas of self-incompatible (SI) species N. alata, N. forgetiana, and N. bonariensis, but not in self-compatible (SC) species N. tabacum, N. plumbaginifolia, N. benthamiana, N. longiflora, and N. glauca. NaStEP contains the vacuolar targeting sequence NPIVL, and immunocytochemistry experiments showed vacuolar localization in unpollinated stigmas. After self-pollination or pollination with pollen from the SC species N. tabacum or N. plumbaginifolia, NaStEP was also found in the stigmatic exudate. The synthesis and presence in the stigmatic exudate of this protein was strongly induced in N. alata following incompatible pollination with N. tabacum pollen. The transfer of NaStEP to the stigmatic exudate was accompanied by perforation of the stigmatic cell wall, which appeared to release the vacuolar contents to the apoplastic space. The increase in NaStEP synthesis after pollination and its presence in the stigmatic exudates suggest that this protein may play a role in the early pollen-stigma interactions that regulate pollen tube growth in Nicotiana.

BIIDXI, a DUF642 cell wall protein, is involved in hypocotyl growth via auxin efflux.

Auxin is involved in hypocotyl elongation in response to different environmental factors. BIIDXI is a cell wall DUF642 protein that participates in the regulation of the degree of pectin-methylesterification of the cell wall in different tissues, including hypocotyls. Under continuous light, bdx-1 seedlings presented longer hypocotyls than those of WT, while BIIDXI-overexpressed hypocotyls were auxin resistant. Auxin accumulation was observed in epidermal cells from bdx-1 hypocotyls, and the distribution pattern of PIN1 proteins differed. Moreover, the gravitropic response of bdx-1, a process that is highly dependent on auxin flux, was increased. In this study, we determined that BIIDXI is involved in hypocotyl elongation through the regulation of auxin flux.

Coping with potential bi-parental inbreeding: limited pollen and seed dispersal and large genets in the dioecious marine angiosperm Thalassia testudinum.

The high prevalence of dioecy in marine angiosperms or seagrasses (>50% of all species) is thought to enforce cross-fertilization. However, seagrasses are clonal plants, and they may still be subject to sibling-mating or bi-parental inbreeding if the genetic neighborhood is smaller than the size of the genets. We tested this by determining the genetic neighborhoods of the dioecious seagrass Thalassia testudinum at two sites (Back-Reef and Mid-Lagoon) in Puerto Morelos Reef Lagoon, Mexico, by measuring dispersal of pollen and seeds in situ, and by fine-scale spatial autocorrelation analysis with eight polymorphic microsatellite DNA markers. Prevalence of inbreeding was verified by estimating pairwise kinship coefficients; and by analysing the genotypes of seedlings grown from seeds in mesocosms. Average dispersal of pollen was 0.3-1.6 m (max. 4.8 m) and of seeds was 0.3-0.4 m (max. 1.8 m), resulting in a neighborhood area of 7.4 m2 (range 3.4-11.4 m2) at Back-Reef and 1.9 (range 1.87-1.92 m2) at Mid-Lagoon. Neighborhood area (Na) derived from spatial autocorrelation was 0.1-20.5 m2 at Back-Reef and 0.1-16.9 m2 at Mid-Lagoon. Maximal extensions of the genets, in 19 × 30 m plots, were 19.2 m (median 7.5 m) and 10.8 m (median 4.8 m) at Back-Reef and Mid-Lagoon. There was no indication of deficit or excess of heterozygotes nor were coefficients of inbreeding (FIS) significant. The seedlings did not show statistically significant deficit of heterozygotes (except for 1 locus at Back-Reef). Contrary to our expectations, we did not find evidence of bi-parental inbreeding in this dioecious seagrass with large genets but small genetic neighborhoods. Proposed mechanisms to avoid bi-parental inbreeding are possible selection against homozygotes during fecundation or ovule development. Additionally, the genets grew highly dispersed (aggregation index Ac was 0.09 and 0.10 for Back-Reef and Mid-Lagoon, respectively); such highly dispersed guerrilla-like clonal growth form likely increases the probability of crossing between different potentially unrelated genets.

Morfo-anatomía del ciclo de vida del helecho Pteridium aquilinum (Dennstaedtiaceae) en cultivo in vitro

Introducción: Pteridium aquilinum es un helecho heliófilo ampliamente distribuido en México. Es una especie pionera que usualmente se encuentra en hábitats alterados y tiene gran relevancia ecológica por sus propiedades alelopáticas, su resistencia al fuego y a condiciones de sequía. Objetivo: Realizar una descripción integral de la forma y ornamentación de las esporas de P. aquilinum, así como de la morfogénesis del gametofito, incluyendo el tipo de germinación y el desarrollo protálico (resaltando su morfología). Además, describir la anatomía del esporofito joven desarrollado en condiciones in vitro. Metodología: Se utilizó microscopía electrónica de barrido y técnica histológica de parafina para la descripción de las fases del gametofito y esporofito. Resultados: Las esporas son globulares y el trilete tiene ornamentación granulada, mientras que su germinación fue de tipo Vittaria y el desarrollo protálico correspondió al tipo Adiantum. Los anteridios se observaron 13 días después de la siembra, mientras que los arquegonios surgieron al día 17. La primera hoja del esporofito apareció entre los días 60 y 70. Al cuarto mes, la fase esporofítica desarrollada in vitro mostró la anatomía típica de la especie a esta edad, dado que no presentó vitrificación. El análisis histológico del rizoma, la base del peciolo, el raquis de primer orden y la lámina mostraron los sistemas de tres tejidos bien diferenciados. Las modificaciones anatómicas observadas in vitro, como una dictiostela monocíclica y sólo una banda de esclerénquima en el rizoma, podrían atribuirse a la edad de los individuos. Por otra parte, los estomas están presentes en la superficie adaxial de la lámina, que corresponde al tipo anomocítico. Aunque estos estomas se formaron en condiciones in vitro, es importante resaltar que son completamente funcionales. Conclusiones: Nuestro trabajo describe por primera vez la morfo-anatomía de las fases gametofítica y esporofítica del ciclo de vida de P. aquilinum en condiciones in vitro. Nuestros resultados posiblemente permitan la exploración con mayor profundidad de las propiedades biológicas, fisiológicas y ecológicas de la especie.

Introduction: Pteridium aquilinum is a heliophilous fern widely distributed in Mexico. It is a pioneer species usually found within disturbed habitats with high ecological relevance because of its allelopathic properties, its resistance to fire and drought conditions. Objective: Provide an integrative description regarding P. aquilinum spores shape and ornamentation, and also on gametophyte morphogenesis, including the type of germination and the prothallic development (highlighting its morphology). Furthermore, the anatomy of young sporophyte grown under in vitro conditions was described. Methods: We used scanning electron microscopy and histological paraffin technique to describe the gametophytic and sporophytic phases. Results: The evaluation of the spores showed the presence of globular morphology and triletes with granulated ornamentation; while their germination was Vittaria-type, the prothallic development corresponded to the Adiantum-type. The antheridia were observed 13 days following to the sowing, whereas archegonia arose at day 17. The first leaf of the sporophyte appeared between days 60 and 70. At fourth month, the in vitro grown sporophyte showed the typical anatomy of the individuals of the species at this age, since it did not exhibit vitrification. The histological analysis of rhizome, the petiole base, first order rachis and lamina showed the three tissue systems well differentiated. The anatomical modifications observed in vitro, such as a non-polycyclic dictyostele and just one band sclerenchyma in the rhizome, may be attributed to the individuals age. Moreover, the stomata are present on the adaxial surface of lamina, corresponding to the anomocytic type. Although these stomata were developed under in vitro conditions, it is important to highlight that they are completely functional. Conclusions: Our work describes for the first time the morpho-anatomy of both the gametophytic and the sporophytic phases in the life cycle of P. aquilinum under in vitro conditions. Our results indicate that this method will allow deeper exploration of biological, physiological and ecological properties of the species.

Frecuencia de infección por Leptospira sp. en ardillas nuca blanca (Sciurus stramineus) en un zoológico de la ciudad de Lima / Frequency of infection by Leptospira sp. in white neck squirrel (Sciurus stramineus) in a zoo of Lima city

El objetivo del estudio fue detectar la frecuencia de anticuerpos contra Leptospira sp en la población de ardillas nuca blanca (Sciurus stramineus) silvestres capturadas en el zoológico Parque de Las Leyendas, Lima. Se colectó 35 muestras de suero de ardillas nuca blanca de ambos sexos, de diferentes edades y zonas del zoológico, para la detección de anticuerpos contra Leptospira sp mediante la prueba de microaglutinación. El 82.3% (29/35) de animales presentó anticuerpos contra Leptospira sp, donde el 60% correspondió al serovar icterohemorraghiae, seguidos por georgia (31.4%), canicola (5.7%), y australis (2.8%). No hubo diferencia estadística entre la presencia de anticuerpos contra Leptospira sp y las variables sexo, edad y área de captura de las ardillas. Los resultados indican que la infección leptospiral está presente en las ardillas nuca blanca pudiendo constituir un riesgo para los animales de la colección faunística y las personas que laboran en el zoológico.

The purpose of the study was to detect the frequency of antibodies against Leptospira sp in the wild neck white squirrel population (Sciurus stramineus) caught in the Parque de las Leyendas Zoo, Lima. Thirty five blood samples were collected from neck white squirrels, males and females of various ages that were trapped in various areas in the zoo. Samples were analyzed for antibodies against Leptospira sp by micro agglutination test. The 82.3% (29/35) of animals had antibodies against Leptospira sp of which 60% corresponded to the icterohemorraghiae serovar, followed by georgia (31.4%), canicola (5.7%), and australis (2.8%). None statistical difference between the presence of antibodies against Leptospira sp and the variables sex, age and area of trapping was found. The results indicated that leptospiral infection is present in the neck white squirrels, and the disease poses a health risk to animals and people working at the zoo.

Frecuencia de anticuerpos contra Toxoplasma gondii en monos Cebus apella criados en cautiverio / Frequency of antibodies against Toxoplasma gondii in Cebus apella monkeys bred in captivity

El presente estudio tuvo como objetivo determinar la frecuencia de portadores de anticuerpos anti-Toxoplasma gondii en primates de la especie Cebus apella en el zoológico del Patronato del Parque de las Leyendas, ubicado en la ciudad de Lima. Se tomaron 62 muestras de suero sanguíneo y se evaluó la presencia de anticuerpos contra T. gondii mediante la prueba de hemaglutinación indirecta (HAI). Se encontró el 90.3 por ciento (56/62) de sueros positivos, sin que hubiera diferencia estadística significativa entre sexo o grupos etáreos (juveniles y adultos). Los resultados mostraron una elevada tasa de primates reactores a este parásito, que puede deberse al elevado número de gatos que transitan libremente en los alrededores de los ambientes asignados a los primates.

The purpose of the present study was to determine the frequency of primates (Cebus apella) carrying anti-Toxoplasma gondii antibodies at the zoo of the Patronato del Parque de las Leyendas, in Lima. Sixty two sera samples were obtained and analyzed by the Indirect Hemaglutination test (HAI) to detect antibodies against T. gondii. The results showed that 90.3 per cent (56/62) sera were positive, and no significant asociation due to sex and age (juvenile and adult) were found. The high rate of positive primates to this parasite could be due to the high number of domestics cats in the premises.