Efficacy of systemic Chemotherapy on high-risk stage II and III Mucnious colon cancer. CHEMUCCA study part I.

BACKGROUND: Locally advanced colon cancer is a high-risk condition for tumour recurrence with poor survival. The current treatment is surgery followed by adjuvant chemotherapy based on fluoropyrimidines and oxaliplatin. This approach has improved the oncological outcomes on this population, however the mucinous condition has not been studied in depth and although the evidence is weak, it is thought to have a worse response to systemic chemotherapy. The CHEMUCCA study aims to answer this question. OBJECTIVE: To evaluate the effectiveness of adjuvant systemic chemotherapy using the disease-free survival for stage II and III mucinous colon cancer who underwent surgical resection plus systemic adjuvant chemotherapy vs. surgery alone. PATIENTS AND METHODS: Retrospective analytical study including patients diagnosed with high-risk stage II and stage III colon cancer, treated between 2010 and 2021, with a minimum follow-up of 3 years. Demographic variables and tumour features were analysed. The primary endpoint was disease-free survival. Log rank test and Cox regression were used. RESULTS: Of 1134 patients with high-risk stage II and III colon cancer disease, 206 (18,17 %) had mucinous histology and 928 (81,83 %) had non-mucinous histology. 708 patients who received adjuvant chemotherapy, 129 (62,62 %) in mucinous group and 579 (62,39 %) in the non-mucinous group. Adjuvant systemic chemotherapy in stage II and III mucinous colon cancer improved the DFS (HR = 0.58 [95 % CI 0.37-0.91]; p = 0,017). However, in a stratified analysis, patients with high-risk stage II mucinous colon cancer showed no benefit with this approach (HR = 0.4541 [95 % CI 0.19-1.03]; p = 0.06). CONCLUSION: Adjuvant chemotherapy has demonstrated to be effective in locally advanced mucinous colorectal cancer improving the oncological outcomes. However, this benefit could be diminished in high-risk stage II mucinous colon cancer patients. The administration of adjuvant chemotherapy on this patient's sub-group must be balanced according to risk versus benefits.

Acute effects on the psychological perception of university students after participation in the "RegulACTION" workshop for the improvement of emotional health and promotion of an active lifestyle.

Introduction: Prospective research in Health Sciences and Sports Sciences warns of the need to design and implement educational program at the different stages of human development, that promote emotional competences, interpersonal competences, an adequate level of healthy physical activity as well as adherence to the Mediterranean diet and a more active lifestyle on a physical and social level. The main objective of the study was to design an intervention program on intra-and interpersonal competences together with emotional education, nutritional education and healthy physical activity, called 'RegulACTION'. Methods: The preliminary study sample consisted of 11 participants aged 21-28 years (M = 5.00, SD = 8.76) (8 female and 3 males) university students. An ad hoc questionnaire was elaborated to evaluate the participant's perception of the usefulness of the 'RegulACTION' experience and a semi-structured interview of 5 questions to assess their perception, identification of their emotions, awareness of their cognitions, emotions and behaviors in the different areas of their lives. Results: The descriptive results show that the participants are receptive to continuing training in the regulation of cognitions (thoughts) and emotions to increase their satisfaction in different areas of their lives. Regarding the qualitative results, the participants' perception, collected verbatim, is that they feel the need to apply the knowledge about personal and social emotions, as well as healthy behavior in terms of nutrition and exercise, in their daily lives. Discussion: The 'RegulACTION' program is designed based on the assessment of the prevalence of mental illness in the young adult and adult population, in line with the literature review in the area of knowledge of the theory of emotions, motivational theories and on the occasion of the development of a workshop organized.

Unveiling the Genetic Blueprint of a Desert Scorpion: A Chromosome-level Genome of Hadrurus arizonensis Provides the First Reference for Parvorder Iurida.

Over 400 million years old, scorpions represent an ancient group of arachnids and one of the first animals to adapt to life on land. Presently, the lack of available genomes within scorpions hinders research on their evolution. This study leverages ultralong nanopore sequencing and Pore-C to generate the first chromosome-level assembly and annotation for the desert hairy scorpion, Hadrurus arizonensis. The assembled genome is 2.23 Gb in size with an N50 of 280 Mb. Pore-C scaffolding reoriented 99.6% of bases into nine chromosomes and BUSCO identified 998 (98.6%) complete arthropod single copy orthologs. Repetitive elements represent 54.69% of the assembled bases, including 872,874 (29.39%) LINE elements. A total of 18,996 protein-coding genes and 75,256 transcripts were predicted, and extracted protein sequences yielded a BUSCO score of 97.2%. This is the first genome assembled and annotated within the family Hadruridae, representing a crucial resource for closing gaps in genomic knowledge of scorpions, resolving arachnid phylogeny, and advancing studies in comparative and functional genomics.

Mutational Profile and Retinal Phenotypes of PCARE-Related Cone-Rod Dystrophies in a Mexican Cohort.

Purpose: The aim of the study is to describe the genotype and phenotype of a Mexican cohort with PCARE-related retinal disease. Methods: The study included 14 patients from 11 unrelated pedigrees with retinal dystrophies who were demonstrated to carry biallelic pathogenic variants in PCARE. Visual assessment methods included best corrected visual acuity, color fundus photography, Goldmann visual field test, kinetic perimetry, dark/light adapted chromatic perimetry, full-field electroretinography, autofluorescence imaging, and spectral domain-optical coherence tomography imaging. Genetic screening was performed either by gene panel sequencing or by exome sequencing. Results: According to the results of multimodal imaging and functional tests, all 14 patients were diagnosed with cone-rod dystrophy. Six different PCARE pathogenic alleles were identified in our cohort, including three novel mutations: c.3048_3049del (p.Tyr1016∗), c.3314_3315del (p.Ser1105∗), and c.551A > G (p.His184Arg). Notably, alleles p.His184Arg, p.Arg613∗, and p.Arg984∗ were present in 18 of the 22 (82%) PCARE alleles from probands in our cohort. Conclusion: Our work expands the PCARE mutational profile by identifying three novel pathogenic variants causing retinal dystrophy. While phenotypic variations occurred among patients, a cone-rod dystrophy pattern was observed in all affected individuals.

Post-Anesthesia Cognitive Dysfunction in Mice Is Associated with an Age-Related Increase in Neuronal Intracellular [Ca2+]-Neuroprotective Effect of Reducing Intracellular [Ca2+]: In Vivo and In Vitro Studies.

Background: Postoperative cognitive dysfunction (POCD) is a common disorder after general anesthesia in elderly patients, the precise mechanisms of which remain unclear. Methods: We investigated the effect of isoflurane with or without dantrolene pretreatment on intracellular calcium concentration ([Ca2+]i), reactive oxygen species (ROS) production, cellular lactate dehydrogenase (LDH) leak, calpain activity, and cognitive function using the Morris water maze test of young (3 months), middle-aged (12-13 months), and aged (24-25 months) C57BL6/J mice. Results: Aged cortical and hippocampal neurons showed chronically elevated [Ca2+]i compared to young neurons. Furthermore, aged hippocampal neurons exhibited higher ROS production, increased LDH leak, and elevated calpain activity. Exposure to isoflurane exacerbated these markers in aged neurons, contributing to increased cognitive deficits in aged mice. Dantrolene pretreatment reduced [Ca2+]i for all age groups and prevented or significantly mitigated the effects of isoflurane on [Ca2+]i, ROS production, LDH leak, and calpain activity in aged neurons. Dantrolene also normalized or improved age-associated cognitive deficits and mitigated the cognitive deficits caused by isoflurane. Conclusions: These findings suggest that isoflurane-induced cytotoxicity and cognitive decline in aging are linked to disruptions in neuronal intracellular processes, highlighting the reduction of [Ca2+]i as a potential therapeutic intervention.

Promiscuous CYP87A enzyme activity initiates cardenolide biosynthesis in plants.

Cardenolides are specialized, steroidal metabolites produced in a wide array of plant families1,2. Cardenolides play protective roles in plants, but these molecules, including digoxin from foxglove (Digitalis spp.), are better known for treatment of congenital heart failure, atrial arrhythmia, various cancers and other chronic diseases3-9. However, it is still unknown how plants synthesize 'high-value', complex cardenolide structures from, presumably, a sterol precursor. Here we identify two cytochrome P450, family 87, subfamily A (CYP87A) enzymes that act on both cholesterol and phytosterols (campesterol and ß-sitosterol) to form pregnenolone, the first committed step in cardenolide biosynthesis in the two phylogenetically distant plants Digitalis purpurea and Calotropis procera. Arabidopsis plants overexpressing these CYP87A enzymes ectopically accumulated pregnenolone, whereas silencing of CYP87A in D. purpurea leaves by RNA interference resulted in substantial reduction of pregnenolone and cardenolides. Our work uncovers the key entry point to the cardenolide pathway, and expands the toolbox for sustainable production of high-value plant steroids via synthetic biology.

Neglected no longer: Phylogenomic resolution of higher-level relationships in Solifugae.

Advanced sequencing technologies have expedited resolution of higher-level arthropod relationships. Yet, dark branches persist, principally among groups occurring in cryptic habitats. Among chelicerates, Solifugae ("camel spiders") is the last order lacking a higher-level phylogeny and have thus been historically characterized as "neglected [arachnid] cousins". Though renowned for aggression, remarkable running speed, and xeric adaptation, inferring solifuge relationships has been hindered by inaccessibility of diagnostic morphological characters, whereas molecular investigations have been limited to one of 12 recognized families. Our phylogenomic dataset via capture of ultraconserved elements sampling all extant families recovered a well-resolved phylogeny, with two distinct groups of New World taxa nested within a broader Paleotropical radiation. Divergence times using fossil calibrations inferred that Solifugae radiated by the Permian, and most families diverged prior to the Paleogene-Cretaceous extinction, likely driven by continental breakup. We establish Boreosolifugae new suborder uniting five Laurasian families, and Australosolifugae new suborder uniting seven Gondwanan families using morphological and biogeographic signal.

Old and cold: Diverse phylogenomic datasets support an ancient transantarctic dispersive route on the scorpion family Bothriuridae in temperate Gondwana.

In this contribution we try to unveil the diversification process of Bothriuridae in temperate Gondwana through dated phylogenomic analyses using UCE and transcriptomics, and including in the analyses species of genera Urophonius and Cercophonius, the most closely related genera of Bothriuridae from South America and Australia respectively. Additionally we explored the hypothesis that the winter activity period of some species of Urophonius, as well as the cold environmental preferences of this genus, could be related to the climatic conditions of the time frame and area in which it evolved. Genus Urophonius was recovered as sister group to Cercophonius using amino acids and UCE. The time frame obtained for the split between South American and Australian bothriurids is 94 Ma., which suggests a dispersal event through temperate Gondwana, before the final breakup of the land bridge of South America-Antarctica-Australia ca. 35 Ma. The split between summer and winter species of Urophonius, taking place at 64 Ma, is considered representative to the turnover time from the summer activity period to the winter activity period in some species of the genus. This time frame is compatible with a period of global warming of the late Cretaceous greenhouse episode that could have triggered this change.

Congruence between ultraconserved element-based matrices and phylotranscriptomic datasets in the scorpion Tree of Life.

Scorpions are ancient and historically renowned for their potent venom. Traditionally, the systematics of this group of arthropods was supported by morphological characters, until recent phylogenomic analyses (using RNAseq data) revealed most of the higher-level taxa to be non-monophyletic. While these phylogenomic hypotheses are stable for almost all lineages, some nodes have been hard to resolve due to minimal taxonomic sampling (e.g. family Chactidae). In the same line, it has been shown that some nodes in the Arachnid Tree of Life show disagreement between hypotheses generated using transcritptomes and other genomic sources such as the ultraconserved elements (UCEs). Here, we compared the phylogenetic signal of transcriptomes vs. UCEs by retrieving UCEs from new and previously published scorpion transcriptomes and genomes, and reconstructed phylogenies using both datasets independently. We reexamined the monophyly and phylogenetic placement of Chactidae, sampling an additional chactid species using both datasets. Our results showed that both sets of genome-scale datasets recovered highly similar topologies, with Chactidae rendered paraphyletic owing to the placement of Nullibrotheas allenii. As a first step toward redressing the systematics of Chactidae, we establish the family Anuroctonidae (new family) to accommodate the genus Anuroctonus.

Reproductive performance of hair ewes and rams implanted with melatonin previous to the anestrus season in northwest Mexico.

Ovine reproductive behavior depends on annual photoperiodic cycle and its impact on endogenous melatonin secretion. In this regard, exogenous melatonin administration previous to the physiological anestrus period could modify the reproductive performance of sheep in the northwest of Mexico. Two independent studies were performed to evaluate such hypothesis in hair sheep implanted with melatonin prior to the anestrus season in latitudes 24° and 25° of Mexico. Study 1 involved 15 rams assigned to one of three treatments receiving 0mg (n=5), 18mg (n=5), or 36mg (n=5) of melatonin subcutaneously. Study variables were measured monthly since implantation (d0) and included testosterone concentration, scrotal circumference, mass motility, individual motility, and sperm concentration. Study 2 included 50 ewes assigned to one of two treatments receiving 0mg (n=25) or 18mg (n=25) of melatonin subcutaneously. In ewes, progesterone concentration and the frequency of females in anestrus were measured during the implantation (-30d), as well as at the beginning (0d) and at the end (45d) of the mating period, while pregnancy rate was determined by ultrasonography 45d after. Continuous variables were analyzed using a mixed effects model considering treatment, time, and the treatment by time interaction as fixed effects. Animal nested within treatment was the random effect. Binary variables were analyzed using the chi-square test. In males, melatonin improved testosterone and sperm concentrations (P<0.05), while in females, a 28% higher pregnancy rate was observed in implanted ewes (P<0.05). Therefore, melatonin enhanced reproductive parameters in both sexes and its exogenous administration previous to the anestrus season in northwest Mexico could be more effective in rams.

Mother-to-infant microbiota transmission and infant microbiota development across multiple body sites.

Early-life microbiota seeding and subsequent development is crucial to future health. Cesarean-section (CS) birth, as opposed to vaginal delivery, affects early mother-to-infant transmission of microbes. Here, we assess mother-to-infant microbiota seeding and early-life microbiota development across six maternal and four infant niches over the first 30 days of life in 120 mother-infant pairs. Across all infants, we estimate that on average 58.5% of the infant microbiota composition can be attributed to any of the maternal source communities. All maternal source communities seed multiple infant niches. We identify shared and niche-specific host/environmental factors shaping the infant microbiota. In CS-born infants, we report reduced seeding of infant fecal microbiota by maternal fecal microbes, whereas colonization with breastmilk microbiota is increased when compared with vaginally born infants. Therefore, our data suggest auxiliary routes of mother-to-infant microbial seeding, which may compensate for one another, ensuring that essential microbes/microbial functions are transferred irrespective of disrupted transmission routes.

Biocatalytic routes to stereo-divergent iridoids.

Thousands of natural products are derived from the fused cyclopentane-pyran molecular scaffold nepetalactol. These natural products are used in an enormous range of applications that span the agricultural and medical industries. For example, nepetalactone, the oxidized derivative of nepetalactol, is known for its cat attractant properties as well as potential as an insect repellent. Most of these naturally occurring nepetalactol-derived compounds arise from only two out of the eight possible stereoisomers, 7S-cis-trans and 7R-cis-cis nepetalactols. Here we use a combination of naturally occurring and engineered enzymes to produce seven of the eight possible nepetalactol or nepetalactone stereoisomers. These enzymes open the possibilities for biocatalytic production of a broader range of iridoids, providing a versatile system for the diversification of this important natural product scaffold.

Biosynthesis of strychnine.

Strychnine is a natural product that, through isolation, structural elucidation and synthetic efforts, shaped the field of organic chemistry. Currently, strychnine is used as a pesticide to control rodents1 because of its potent neurotoxicity2,3. The polycyclic architecture of strychnine has inspired chemists to develop new synthetic transformations and strategies to access this molecular scaffold4, yet it is still unknown how plants create this complex structure. Here we report the biosynthetic pathway of strychnine, along with the related molecules brucine and diaboline. Moreover, we successfully recapitulate strychnine, brucine and diaboline biosynthesis in Nicotiana benthamiana from an upstream intermediate, thus demonstrating that this complex, pharmacologically active class of compounds can now be harnessed through metabolic engineering approaches.

Bacterial and fungal communities in tracheal aspirates of intubated COVID-19 patients: a pilot study.

Co-infections with bacterial or fungal pathogens could be associated with severity and outcome of disease in COVID-19 patients. We, therefore, used a 16S and ITS-based sequencing approach to assess the biomass and composition of the bacterial and fungal communities in endotracheal aspirates of intubated COVID-19 patients. Our method combines information on bacterial and fungal biomass with community profiling, anticipating the likelihood of a co-infection is higher with (1) a high bacterial and/or fungal biomass combined with (2) predominance of potentially pathogenic microorganisms. We tested our methods on 42 samples from 30 patients. We observed a clear association between microbial outgrowth (high biomass) and predominance of individual microbial species. Outgrowth of pathogens was in line with the selective pressure of antibiotics received by the patient. We conclude that our approach may help to monitor the presence and predominance of pathogens and therefore the likelihood of co-infections in ventilated patients, which ultimately, may help to guide treatment.

Chronic Elevation of Skeletal Muscle [Ca2+]i Impairs Glucose Uptake. An in Vivo and in Vitro Study.

Skeletal muscle is the primary site of insulin-mediated glucose uptake through the body and, therefore, an essential contributor to glucose homeostasis maintenance. We have recently provided evidence that chronic elevated intracellular Ca2+ concentration at rest [(Ca2+)i] compromises glucose homeostasis in malignant hyperthermia muscle cells. To further investigate how chronic elevated muscle [Ca2+]i modifies insulin-mediated glucose homeostasis, we measured [Ca2+]i and glucose uptake in vivo and in vitro in intact polarized muscle cells from glucose-intolerant RYR1-p.R163C and db/db mice. Glucose-intolerant RYR1-p.R163C and db/db mice have significantly elevated muscle [Ca2+]i and reduced muscle glucose uptake compared to WT muscle cells. Dantrolene treatment (1.5 mg/kg IP injection for 2 weeks) caused a significant reduction in fasting blood glucose levels and muscle [Ca2+]i and increased muscle glucose uptake compared to untreated RYR1-p.R163C and db/db mice. Furthermore, RYR1-p.R163C and db/db mice had abnormal basal insulin levels and response to glucose-stimulated insulin secretion. In vitro experiments conducted on single muscle fibers, dantrolene improved insulin-mediated glucose uptake in RYR1-p.R163C and db/db muscle fibers without affecting WT muscle fibers. In muscle cells with chronic elevated [Ca2+]i, GLUT4 expression was significantly lower, and the subcellular fraction (plasma membrane/cytoplasmic) was abnormal compared to WT. The results of this study suggest that i) Chronic elevated muscle [Ca2+]i decreases insulin-stimulated glucose uptake and consequently causes hyperglycemia; ii) Reduced muscle [Ca2+]i by dantrolene improves muscle glucose uptake and subsequent hyperglycemia; iii) The mechanism by which chronic high levels of [Ca2+]i interfere with insulin action appears to involve the expression of GLUT4 and its subcellular fractionation.

Phylogeny-Aware Chemoinformatic Analysis of Chemical Diversity in Lamiaceae Enables Iridoid Pathway Assembly and Discovery of Aucubin Synthase.

Countless reports describe the isolation and structural characterization of natural products, yet this information remains disconnected and underutilized. Using a cheminformatics approach, we leverage the reported observations of iridoid glucosides with the known phylogeny of a large iridoid producing plant family (Lamiaceae) to generate a set of biosynthetic pathways that best explain the extant iridoid chemical diversity. We developed a pathway reconstruction algorithm that connects iridoid reports via reactions and prunes this solution space by considering phylogenetic relationships between genera. We formulate a model that emulates the evolution of iridoid glucosides to create a synthetic data set, used to select the parameters that would best reconstruct the pathways, and apply them to the iridoid data set to generate pathway hypotheses. These computationally generated pathways were then used as the basis by which to select and screen biosynthetic enzyme candidates. Our model was successfully applied to discover a cytochrome P450 enzyme from Callicarpa americana that catalyzes the oxidation of bartsioside to aucubin, predicted by our model despite neither molecule having been observed in the genus. We also demonstrate aucubin synthase activity in orthologues of Vitex agnus-castus, and the outgroup Paulownia tomentosa, further strengthening the hypothesis, enabled by our model, that the reaction was present in the ancestral biosynthetic pathway. This is the first systematic hypothesis on the epi-iridoid glucosides biosynthesis in 25 years and sets the stage for streamlined work on the iridoid pathway. This work highlights how curation and computational analysis of widely available structural data can facilitate hypothesis-based gene discovery.

Phylogenomics of Scorpions Reveal Contemporaneous Diversification of Scorpion Mammalian Predators and Mammal-Active Sodium Channel Toxins.

Scorpions constitute a charismatic lineage of arthropods and comprise more than 2500 described species. Found throughout various tropical and temperate habitats, these predatory arachnids have a long evolutionary history, with a fossil record that began in the Silurian. While all scorpions are venomous, the asymmetrically diverse family Buthidae harbors nearly half the diversity of extant scorpions, and all but one of the 58 species that are medically significant to humans. However, the lack of a densely sampled scorpion phylogeny has hindered broader inferences of the diversification dynamics of scorpion toxins. To redress this gap, we assembled a phylogenomic data set of 100 scorpion venom gland transcriptomes and genomes, emphasizing the sampling of highly toxic buthid genera. To infer divergence times of venom gene families, we applied a phylogenomic node dating approach for the species tree in tandem with phylostratigraphic bracketing to estimate the minimum ages of mammal-specific toxins. Our analyses establish a robustly supported phylogeny of scorpions, particularly with regard to relationships between medically significant taxa. Analysis of venom gene families shows that mammal-active sodium channel toxins (NaTx) have independently evolved in five lineages within Buthidae. Temporal windows of mammal-targeting toxin origins are correlated with the basal diversification of major scorpion mammal predators such as shrews, bats, and rodents. These results suggest an evolutionary model of relatively recent diversification of buthid NaTx homologs in response to the diversification of scorpion predators. [Adaptation; arachnids; phylogenomic dating; phylostratigraphy; venom.].