Maternally-loaded factors in the egg accumulate during oogenesis and are essential for the acquisition of oocyte and egg developmental competence to ensure the production of viable embryos. However, their molecular nature and functional importance remain poorly understood. Here, we present a collection of 9 recessive maternal-effect mutants identified in a zebrafish forward genetic screen that reveal unique molecular insights into the mechanisms controlling the vertebrate oocyte-to-embryo transition.
View Article and Find Full Text PDFSaxitoxin (STX) represents a marine toxin of significant concern due to its deleterious implications for aquatic ecosystems and public food safety. As a potent paralytic agent, the role of STX in obstructing voltage-gated sodium channels (VGSCs) is well-characterized. Yet, the mechanistic details underlying its low-dose toxicity remain largely enigmatic.
View Article and Find Full Text PDFThe vertebral column, or spine, provides mechanical support and determines body axis posture and motion. The most common malformation altering spine morphology and function is adolescent idiopathic scoliosis (AIS), a three-dimensional spinal deformity that affects approximately 4% of the population worldwide. Due to AIS genetic heterogenicity and the lack of suitable animal models for its study, the etiology of this condition remains unclear, thus limiting treatment options.
View Article and Find Full Text PDFThe feeding behavior in fish is a complex activity that relies on the ability of the brain to integrate multiple signals to produce appropriate responses in terms of food intake, energy expenditure, and metabolic activity. Upon stress cues including viral infection or mediators such as the proinflammatory cytokines, prostaglandins, and cortisol, both Pomc and Npy/Agrp neurons from the hypothalamus are stimulated, thus triggering a response that controls both energy storage and expenditure. However, how appetite modulators or neuro-immune cues link pathogenesis and energy homeostasis in fish remains poorly understood.
View Article and Find Full Text PDFFertilization by multiple sperm leads to lethal chromosomal number abnormalities, failed embryo development, and miscarriage. In some vertebrate and invertebrate eggs, the so-called cortical reaction contributes to their activation and prevents polyspermy during fertilization. This process involves biogenesis, redistribution, and subsequent accumulation of cortical granules (CGs) at the female gamete cortex during oogenesis.
View Article and Find Full Text PDFBackground: The communication between the brain and the immune system is a cornerstone in animal physiology. This interaction is mediated by immune factors acting in both health and pathogenesis, but it is unclear how these systems molecularly and mechanistically communicate under changing environmental conditions. Behavioural fever is a well-conserved immune response that promotes dramatic changes in gene expression patterns during ectotherms' thermoregulatory adaptation, including those orchestrating inflammation.
View Article and Find Full Text PDFBackground: Deconstructing a complex procedure improves skills learning, but no model has covered all relevant Percutaneous Dilatational Tracheostomy (PDT) procedural aspects. Moreover, the heterogeneity of techniques described may hinder trainees' competency acquisition. Our objective was to develop a PDT model for procedural training that includes a comprehensive step-by-step design.
View Article and Find Full Text PDFBackground: Supplementation of vitamin B12 in older adults is a common practice to avoid vitamin B12 insufficiency. However, there is a paucity of information about the effects of cobalamin excess.
Aim: To asses any potential effects of high levels vitamin B12 on mortality on adults aged ≥ 65 years admitted to an internal medicine service.
Axis specification of the zebrafish embryo begins during oogenesis and relies on proper formation of well-defined cytoplasmic domains within the oocyte. Upon fertilization, maternally-regulated cytoplasmic flow and repositioning of dorsal determinants establish the coordinate system that will build the structure and developmental body plan of the embryo. Failure of specific genes that regulate the embryonic coordinate system leads to catastrophic loss of body structures.
View Article and Find Full Text PDFUnlabelled: Proper teaching of the technical skills necessary to perform a medical procedure begins with its breakdown into its constituent steps. Currently available methodologies require substantial resources and their results may be biased. Therefore, it is difficult to generate the necessary breakdown capable of supporting a procedural curriculum.
View Article and Find Full Text PDFProcedural training is relevant for physicians who perform surgical procedures. In the medical education field, instructors who teach surgical procedures need to understand how their students are learning to give them feedback and assess them objectively. The sequence of steps of surgical procedures is an aspect rarely considered in medical education, and state-of-the-art tools for giving feedback and assessing students do not focus on this perspective.
View Article and Find Full Text PDFForward genetic screens remain at the forefront of biology as an unbiased approach for discovering and elucidating gene function at the organismal and molecular level. Past mutagenesis screens targeting maternal-effect genes identified a broad spectrum of phenotypes ranging from defects in oocyte development to embryonic patterning. However, earlier vertebrate screens did not reach saturation, anticipated classes of phenotypes were not uncovered, and technological limitations made it difficult to pinpoint the causal gene.
View Article and Find Full Text PDFBackground: Procedural skills are key to good clinical results, and training in them involves a significant amount of resources. Control-flow analysis (ie, the order in which a process is performed) can provide new information for those who train and plan procedural training. This study outlines the steps required for control-flow analysis using process mining techniques in training in an ultrasound-guided internal jugular central venous catheter placement using a simulation.
View Article and Find Full Text PDFDeveloping high levels of competence in the execution of surgical procedures through training is a key factor for obtaining good clinical results in healthcare. To improve the effectiveness of the training, it is advisable to provide feedback to each student tailored to how the student has performed the procedure on each occasion. Current state-of-the-art feedback is based on Checklists and Global Rating Scales, which indicate whether all process steps have been carried out and the quality of each execution step.
View Article and Find Full Text PDFThe centrosomal protein γ-tubulin is part of the cytoplasmic γ-tubulin small (γ-TuSCs) and large complexes (γ-TuRCs). Both, molecular and cellular evidence indicate that γ-tubulin plays a central role in microtubule nucleation and mitotic spindle formation. However, the molecular mechanisms of complex formation and subsequent biological roles in animal development remain unclear.
View Article and Find Full Text PDFHippo signaling is a critical pathway that integrates extrinsic and intrinsic mechanical cues to regulate organ size. Despite its essential role in organogenesis, little is known about its role in cell fate specification and differentiation. Here, we unravel a novel and unexpected role of the Hippo pathway effector Taz () in controlling the size, shape and fate of a unique cell in the zebrafish ovary.
View Article and Find Full Text PDFBackground: Propofol and remifentanil are commonly combined during total intravenous anesthesia. The impact of remifentanil in this relationship is poorly quantified in children. Derivation of an integrated pharmacokinetic and pharmacodynamic propofol model, containing remifentanil pharmacodynamic interaction information, enables propofol effect-site target-controlled infusion in children with a better prediction of its hypnotic effect when both drugs are combined.
View Article and Find Full Text PDFThe immune regulatory properties of IL-33 have indicated that this cytokine has the capacity to target several immune cells under a variety of immunological responses, including overt inflammation and tolerance. Due to its versatile mechanistics, we sought to investigate the role of IL-33 on mesenchymal stem cells (MSC), a population of cells with recognizable modulatory functions. Our data indicates that IL-33 does not affect the expression of classical MSC markers such as CD29, CD44 and CD73, or the lack of CD45, CD11b and CD117.
View Article and Find Full Text PDFUnderstanding how the genome instructs the phenotypic characteristics of an organism is one of the major scientific endeavors of our time. Advances in genetics have progressively deciphered the inheritance, identity and biological relevance of genetically encoded information, contributing to the rise of several, complementary omic disciplines. One of them is phenomics, an emergent area of biology dedicated to the systematic multi-scale analysis of phenotypic traits.
View Article and Find Full Text PDFEstablishment and movement of cytoplasmic domains is of great importance for the emergence of cell polarity, germline segregation, embryonic axis specification and correct sorting of organelles and macromolecules into different embryonic cells. The zebrafish oocyte, egg and zygote are valuable material for the study of cytoplasmic domains formation and dynamics during development. In this review we examined how cytoplasmic domains form and are relocated during zebrafish early embryogenesis.
View Article and Find Full Text PDFSince they were first described, mesenchymal stem cells (MSCs) have been shown to have important effector mechanisms and the potential for use in cell therapy. A great deal of research has been focused on unveiling how MSCs contribute to anti-inflammatory responses, including describing several cell populations involved and identifying soluble and other effector molecules. In this review, we discuss some of the contemporary evidence for use of MSCs in the field of immune tolerance, with a special emphasis on transplantation.
View Article and Find Full Text PDFUnlabelled: Neonates and small infants with craniofacial malformation may be very difficult or impossible to mask ventilate or intubate. We would like to report the fiberoptic intubation of a small infant with Treacher Collins Syndrome using the technique described by Ellis et al.
Case Report: An one month-old infant with Treacher Collins Syndrome was scheduled for mandibular surgery under general endotracheal anesthesia.
The vertebrate embryonic dorsoventral axis is established and patterned by Wnt and bone morphogenetic protein (BMP) signaling pathways, respectively. Whereas Wnt signaling establishes the dorsal side of the embryo and induces the dorsal organizer, a BMP signaling gradient patterns tissues along the dorsoventral axis. Early Wnt signaling is provided maternally, whereas BMP ligand expression in the zebrafish is zygotic, but regulated by maternal factors.
View Article and Find Full Text PDFBackground: The propofol pharmacokinetic model derived by Kataria et al. was recently modified to perform effect-site target-controlled infusion (TCI). Effect-site concentration (Ce) targets to induce general anesthesia with this model in children have not been described.
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