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Obstetrics and Gynecology Sep 2023The distinction between “pregnancy viability” and “fetal viability” indicates the need for care and clarity when using the term “viability” in clinical...
The distinction between “pregnancy viability” and “fetal viability” indicates the need for care and clarity when using the term “viability” in clinical practice and guidance.
Topics: Humans; Gestational Age; Fetal Viability
PubMed: 37535950
DOI: 10.1097/AOG.0000000000005280 -
Biology Letters Aug 2023Palaeoecological deductions are vital for understanding the evolution and diversification of species within prehistoric environments. This review highlights the... (Review)
Review
Palaeoecological deductions are vital for understanding the evolution and diversification of species within prehistoric environments. This review highlights the multitude of ways in which the microanatomy and microscopic structure of bones enables palaeoecological deductions. The occurrence of growth marks in bones is discussed, and their usefulness in deducing the ontogenetic status and age of individuals is considered, as well as how such marks in bones permit the assessment of the growth dynamics of individuals and species. Here osteohistology is shown to provide insight into the structure of past populations, as well as ecological relationships between individuals. In addition, the response of bones to trauma, disease and moulting is considered. Finally, I explore how osteohistology can give insight into ecomorphological adaptations, such as filter feeding, probe feeding and saltatorial locomotion. Methodological advances in three-dimensional microtomography and synchrotron scanning bodes well for future studies in osteohistology and despite some compromises in terms of tissue identity, circumvents the crucial issue of destructive analyses.
Topics: Humans; Locomotion; Molting
PubMed: 37607578
DOI: 10.1098/rsbl.2023.0245 -
Cellular and Molecular Life Sciences :... Jul 2023Kindlin-2 is critical for development and homeostasis of key organs, including skeleton, liver, islet, etc., yet its role in modulating angiogenesis is unknown. Here, we...
Kindlin-2 is critical for development and homeostasis of key organs, including skeleton, liver, islet, etc., yet its role in modulating angiogenesis is unknown. Here, we report that sufficient KINDLIN-2 is extremely important for NOTCH-mediated physiological angiogenesis. The expression of KINDLIN-2 in HUVECs is significantly modulated by angiogenic factors such as vascular endothelial growth factor A or tumor necrosis factor α. A strong co-localization of CD31 and Kindlin-2 in tissue sections is demonstrated by immunofluorescence staining. Endothelial-cell-specific Kindlin-2 deletion embryos die on E10.5 due to hemorrhage caused by the impaired physiological angiogenesis. Experiments in vitro show that vascular endothelial growth factor A-induced multiple functions of endothelial cells, including migration, matrix proteolysis, morphogenesis and sprouting, are all strengthened by KINDLIN-2 overexpression and severely impaired in the absence of KINDLIN-2. Mechanistically, we demonstrate that KINDLIN-2 inhibits the release of Notch intracellular domain through binding to and maintaining the integrity of NOTCH1. The impaired angiogenesis and avascular retinas caused by KINDLIN-2 deficiency can be rescued by DAPT, an inhibitor of γ-secretase which releases the intracellular domain from NOTCH1. Moreover, we demonstrate that high glucose stimulated hyperactive angiogenesis by increasing KINDLIN-2 expression could be prevented by KINDLIN-2 knockdown, indicating Kindlin-2 as a potential therapeutic target in treatment of diabetic retinopathy. Our study for the first time demonstrates the significance of Kindlin-2 in determining Notch-mediated angiogenesis during development and highlights Kindlin-2 as the potential therapeutic target in angiogenic diseases, such as diabetic retinopathy.
Topics: Humans; Cardiovascular Physiological Phenomena; Diabetic Retinopathy; Endothelial Cells; Morphogenesis; Vascular Endothelial Growth Factor A
PubMed: 37480504
DOI: 10.1007/s00018-023-04866-w -
Genetics Jun 2024Since the days of Ramón y Cajal, the vast diversity of neuronal and particularly dendrite morphology has been used to catalog neurons into different classes. Dendrite... (Review)
Review
Since the days of Ramón y Cajal, the vast diversity of neuronal and particularly dendrite morphology has been used to catalog neurons into different classes. Dendrite morphology varies greatly and reflects the different functions performed by different types of neurons. Significant progress has been made in our understanding of how dendrites form and the molecular factors and forces that shape these often elaborately sculpted structures. Here, we review work in the nematode Caenorhabditis elegans that has shed light on the developmental mechanisms that mediate dendrite morphogenesis with a focus on studies investigating ciliated sensory neurons and the highly elaborated dendritic trees of somatosensory neurons. These studies, which combine time-lapse imaging, genetics, and biochemistry, reveal an intricate network of factors that function both intrinsically in dendrites and extrinsically from surrounding tissues. Therefore, dendrite morphogenesis is the result of multiple tissue interactions, which ultimately determine the shape of dendritic arbors.
Topics: Animals; Caenorhabditis elegans; Dendrites; Morphogenesis; Caenorhabditis elegans Proteins; Sensory Receptor Cells
PubMed: 38785371
DOI: 10.1093/genetics/iyae056 -
Annual Review of Vision Science Sep 2023Proper eye structure is essential for visual function: Multiple essential eye tissues must take shape and assemble into a precise three-dimensional configuration.... (Review)
Review
Proper eye structure is essential for visual function: Multiple essential eye tissues must take shape and assemble into a precise three-dimensional configuration. Accordingly, alterations to eye structure can lead to pathological conditions of visual impairment. Changes in eye shape can also be adaptive over evolutionary time. Eye structure is first established during development with the formation of the optic cup, which contains the neural retina, retinal pigment epithelium, and lens. This crucial yet deceptively simple hemispherical structure lays the foundation for all later elaborations of the eye. Building on descriptions of the embryonic eye that started with hand drawings and micrographs, the field is beginning to identify mechanisms driving dynamic changes in three-dimensional cell and tissue shape. A combination of molecular genetics, imaging, and pharmacological approaches is defining connections among transcription factors, signaling pathways, and the intracellular machinery governing the emergence of this crucial structure.
Topics: Animals; Vertebrates; Retina; Retinal Pigment Epithelium; Vision, Low; Morphogenesis
PubMed: 37040791
DOI: 10.1146/annurev-vision-100720-111125 -
Cells Dec 2023The Hedgehog (Hh) pathway plays a crucial role in embryonic development, acting both as a morphogenic signal that organizes tissue formation and a potent mitogenic... (Review)
Review
The Hedgehog (Hh) pathway plays a crucial role in embryonic development, acting both as a morphogenic signal that organizes tissue formation and a potent mitogenic signal driving cell proliferation. Dysregulated Hh signaling leads to various developmental defects in the brain. This article aims to review the roles of Hh signaling in the development of the neocortex in the mammalian brain, focusing on its regulation of neural progenitor proliferation and neuronal production. The review will summarize studies on genetic mouse models that have targeted different components of the Hh pathway, such as the ligand Shh, the receptor Ptch1, the GPCR-like transducer Smo, the intracellular transducer Sufu, and the three Gli transcription factors. As key insights into the Hh signaling transduction mechanism were obtained from mouse models displaying neural tube defects, this review will also cover some studies on Hh signaling in neural tube development. The results from these genetic mouse models suggest an intriguing hypothesis that elevated Hh signaling may play a role in the gyrification of the brain in certain species. Additionally, the distinctive production of GABAergic interneurons in the dorsal cortex in the human brain may also be linked to the extension of Hh signaling from the ventral to the dorsal brain region. Overall, these results suggest key roles of Hh signaling as both a morphogenic and mitogenic signal during the forebrain development and imply the potential involvement of Hh signaling in the evolutionary expansion of the neocortex.
Topics: Female; Pregnancy; Humans; Animals; Mice; Hedgehog Proteins; Embryonic Development; Morphogenesis; Biological Evolution; Neocortex; Mammals
PubMed: 38201225
DOI: 10.3390/cells13010021 -
Nature Communications Aug 2023Astrocytes are intimately linked with brain blood vessels, an essential relationship for neuronal function. However, astroglial factors driving these physical and...
Astrocytes are intimately linked with brain blood vessels, an essential relationship for neuronal function. However, astroglial factors driving these physical and functional associations during postnatal brain development have yet to be identified. By characterizing structural and transcriptional changes in mouse cortical astrocytes during the first two postnatal weeks, we find that high-mobility group box 1 (Hmgb1), normally upregulated with injury and involved in adult cerebrovascular repair, is highly expressed in astrocytes at birth and then decreases rapidly. Astrocyte-selective ablation of Hmgb1 at birth affects astrocyte morphology and endfoot placement, alters distribution of endfoot proteins connexin43 and aquaporin-4, induces transcriptional changes in astrocytes related to cytoskeleton remodeling, and profoundly disrupts endothelial ultrastructure. While lack of astroglial Hmgb1 does not affect the blood-brain barrier or angiogenesis postnatally, it impairs neurovascular coupling and behavior in adult mice. These findings identify astroglial Hmgb1 as an important player in postnatal gliovascular maturation.
Topics: Animals; Mice; Aquaporin 4; Astrocytes; Blood-Brain Barrier; Brain; Morphogenesis; HMGB1 Protein
PubMed: 37587100
DOI: 10.1038/s41467-023-40682-3 -
International Journal of Molecular... Nov 2023The gilthead seabream, one of the most important species in Mediterranean aquaculture, with an increasing status of exploitation in terms of production volume and... (Review)
Review
The gilthead seabream, one of the most important species in Mediterranean aquaculture, with an increasing status of exploitation in terms of production volume and aquafarming technologies, has become an important research topic over the years. The accumulation of knowledge from several studies conducted during recent decades on their functional and biological characteristics has significantly improved their aquacultural aspects, namely their reproductive success, survival, and growth. Despite the remarkable progress in the aquaculture industry, hatchery conditions are still far from ideal, resulting in frequent abnormalities at the beginning of intensive culture, entailing significant economic losses. Those deformities are induced during the embryonic and post-embryonic periods of life, and their development is still poorly understood. In the present review, we created a comprehensive synthesis that covers the various aspects of skeletal morphogenesis and anomalies in the gilthead seabream, highlighting the genetic, environmental, and nutritional factors contributing to bone deformities and emphasized the potential of the gilthead seabream as a model organism for understanding bone morphogenesis in both aquaculture and translational biological research. This review article addresses the existing lack in the literature regarding gilthead seabream bone deformities, as there are currently no comprehensive reviews on this subject.
Topics: Animals; Sea Bream; Aquaculture; Morphogenesis
PubMed: 38003219
DOI: 10.3390/ijms242216030 -
Nature Communications Oct 2023The hippocampus plays major roles in learning and memory, and its formation requires precise coordination of patterning, cell proliferation, differentiation, and...
The hippocampus plays major roles in learning and memory, and its formation requires precise coordination of patterning, cell proliferation, differentiation, and migration. Here we removed the chromatin-association capability of KDM2B in the progenitors of developing dorsal telencephalon (Kdm2b) to discover that Kdm2b hippocampus, particularly the dentate gyrus, became drastically smaller with disorganized cellular components and structure. Kdm2b mice display prominent defects in spatial memory, motor learning and fear conditioning, resembling patients with KDM2B mutations. The migration and differentiation of neural progenitor cells is greatly impeded in the developing Kdm2b hippocampus. Mechanism studies reveal that Wnt signaling genes in developing Kdm2b hippocampi are de-repressed due to reduced enrichment of repressive histone marks by polycomb repressive complexes. Activating the Wnt signaling disturbs hippocampal neurogenesis, recapitulating the effect of KDM2B loss. Together, we unveil a previously unappreciated gene repressive program mediated by KDM2B that controls progressive fate specifications and cell migration, hence morphogenesis of the hippocampus.
Topics: Animals; Humans; Mice; Cell Differentiation; Hippocampus; Neurogenesis; Polycomb-Group Proteins; Wnt Signaling Pathway
PubMed: 37838801
DOI: 10.1038/s41467-023-42322-2 -
Biology Open Aug 2023The basement membrane (BM) is a thin, planar-organized extracellular matrix that underlies epithelia and surrounds most organs. During development, the BM is highly... (Review)
Review
The basement membrane (BM) is a thin, planar-organized extracellular matrix that underlies epithelia and surrounds most organs. During development, the BM is highly dynamic and simultaneously provides mechanical properties that stabilize tissue structure and shape organs. Moreover, it is important for cell polarity, cell migration, and cell signaling. Thereby BM diverges regarding molecular composition, structure, and modes of assembly. Different BM organization leads to various physical features. The mechanisms that regulate BM composition and structure and how this affects mechanical properties are not fully understood. Recent studies show that precise control of BM deposition or degradation can result in BMs with locally different protein densities, compositions, thicknesses, or polarization. Such heterogeneous matrices can induce temporospatial force anisotropy and enable tissue sculpting. In this Review, I address recent findings that provide new perspectives on the role of the BM in morphogenesis.
Topics: Basement Membrane; Morphogenesis; Extracellular Matrix; Cell Movement
PubMed: 37531197
DOI: 10.1242/bio.059980