Congenital scoliosis (CS) is a type of vertebral malformation for which the etiology remains elusive. The notochord is pivotal for vertebrae development, but its role in CS is still understudied. Here, we generated a zebrafish knockout of ptk7a, a planar cell polarity (PCP) gene that is essential for convergence and extension (C&E) of the notochord, and detected congenital scoliosis-like vertebral malformations (CVMs).
View Article and Find Full Text PDFOsteocytes' response to dynamic loading plays a crucial role in regulating the bone mass but quickly becomes saturated such that downstream induction of bone formation plateaus. The underlying mechanisms that downregulate osteocytes' sensitivity and overall response to loading remain unknown. In other cell types, purinergic signaling through the P2Y2 receptor has the potential to downregulate the sensitivity to loading by modifying cell stiffness through actin polymerization and cytoskeleton organization.
View Article and Find Full Text PDFCellular biomechanics plays critical roles in cancer metastasis and tumor progression. Existing studies on cancer cell biomechanics are mostly conducted in flat 2D conditions, where cells' behavior can differ considerably from those in 3D physiological environments. Despite great advances in developing 3D models, probing cellular elasticity in 3D conditions remains a major challenge for existing technologies.
View Article and Find Full Text PDFSurface browning of plant-derived fresh-cut products is mainly caused by conversion of the phenolic compounds into o-quinones under tyrosinase catalysis. In this study, the rarely reported complex tannins from Euryale ferox seed shell (ECTs) constituted by the units of 35.60% condensed tannins and 64.
View Article and Find Full Text PDFNeural tube closure (NTC) is a critical process during embryonic development. Failure in this process can lead to neural tube defects, causing congenital malformations or even mortality. NTC involves a series of mechanisms on genetic, molecular, and mechanical levels.
View Article and Find Full Text PDFBackground: Epithelial-mesenchymal transition (EMT) is a biological process where epithelial cells lose their adhesive properties and gain invasive, metastatic, and mesenchymal properties. Maintaining the balance between the epithelial and mesenchymal stage is essential for tissue homeostasis. Many of the genes promoting mesenchymal transformation have been identified; however, our understanding of the genes responsible for maintaining the epithelial phenotype is limited.
View Article and Find Full Text PDFMultimodal optical techniques are useful for the comprehensive characterization of material properties. In this work, we developed a new, to the best of our knowledge, multimodal technology that can simultaneously measure a subset of mechanical, optical, and acoustical properties of the sample and is based on the integration of Brillouin (Br) and photoacoustic (PA) microscopy. The proposed technique can acquire co-registered Br and PA signals from the sample.
View Article and Find Full Text PDFBrillouin microscopy based on spontaneous Brillouin scattering has emerged as a unique elastography technique because of its merit of non-contact, label-free, and high-resolution mechanical imaging of biological cell and tissue. Recently, several new optical modalities based on stimulated Brillouin scattering have been developed for biomechanical research. As the scattering efficiency of the stimulated process is much higher than its counterpart in the spontaneous process, stimulated Brillouin-based methods have the potential to significantly improve the speed and spectral resolution of existing Brillouin microscopy.
View Article and Find Full Text PDFMultimodal optical imaging techniques are useful for various applications, including imaging biological samples for providing comprehensive material properties. In this work, we developed a new modality that can measure a set of mechanical, optical, and acoustical properties of a sample at microscopic resolution, which is based on the integration of Brillouin (Br) and photoacoustic (PA) microscopy. The proposed multimodal imaging technique not only can acquire co-registered Br and PA signals but also allows us to utilize the sound speed measured by PA to quantify the sample’s refractive index, which is a fundamental property of the material and cannot be measured by either technique individually.
View Article and Find Full Text PDFPurpose: This study aimed to summarize the clinical characteristics and explore the risk factors for cerebral cavernous malformation (CCM)-related epilepsy (CRE).
Methods: We retrospectively analyzed the clinical data of patients with CCM in our cerebral vascular malformations database. Descriptive statistics were used to present the clinical characteristics of CRE patients.
Objective: The analysis of motorcyclists' intention to drink and ride can help reduce the possibility of accidents caused by the relevant behavior of motorcyclists. The main objectives of this study are to identify important factors in motorcyclists' intention to drink and ride and to make some recommendations that could effectively reduce their riding intention after drinking.
Methods: To explore the effects of demographic and psychological variables on motorcyclists' behavioral intention to drink and ride, a questionnaire based on the extended theory of planned behavior was designed.
is a perennial herbaceous plant that contains many beneficial ginsenosides with diverse pharmacological effects. 24(R)-pseudoginsenoside F is specific to . , a useful biomarker for distinguishing this species from other related plants.
View Article and Find Full Text PDFTerahertz (THz) waves are electromagnetic waves with frequency in the range from 0.1 to 10 THz. THz waves have great potential in the biomedical field, especially in cancer diagnosis, because they exhibit low ionization energy and can be used to discern most biomolecules based on their spectral fingerprints.
View Article and Find Full Text PDFTerahertz wave has a good ability to identify biomolecules due to its fingerprint spectrum characteristics. However, the minimum detectable limit of terahertz technology by the conventional tablet pressing method is on the order of milligrams, which cannot meet the application requirements of low concentration detection in the biomedical field-near or below micrograms. Here, we proposed a method to enhance the detection sensitivity by designing a metamaterial chip with the absorption-induced transparency (AIT) effect, which can enhance the interaction between terahertz waves and biomolecules and lower the detectable limit.
View Article and Find Full Text PDFAn effective sustained-release peroral drug delivery system is needed for chemotherapy. Here, we show that such a system can be achieved by designing polymeric nanomicelles combining mucoadhesion, enhanced absorption and controlled release. Chitosan and glyceryl-monooleate have many desirable properties, so we synthesized a novel chitosan derivative, chitosan-conjugated glyceryl monooleate.
View Article and Find Full Text PDFThe objective of this study is to demonstrate the feasibility of using solubility parameter as guidance for the design and identification of a stable micellar system with a high drug loading capacity for oral drug delivery. Using hydroxycamptothecin (HCPT) as a model drug, the effect of three hydrophobic blocks (fatty glycerides) grafted onto chitosan on the drug loading and stability of HCPT-loaded micellar nanoparticles formed by pH precipitation method were studied systematically. The Flory-Huggins interaction parameter (χFH) calculated by the group contribution method (GCM) and molecular dynamics simulation (MDS) was used to assess the compatibility between HCPT and the copolymers.
View Article and Find Full Text PDFThe objective of this paper is to elucidate the influence of fatty glyceride chain length in chitosan copolymers on the peroral absorption of enoxaparin. First of all, a series of chitosan copolymers with glyceryl monocaprylate (GM8), glyceryl monolaurate (GM12) and glyceryl monostearate (GM18) as the hydrophobic part were synthesized. The structure of the copolymers was characterized using proton nuclear magnetic resonance.
View Article and Find Full Text PDFIn an effort to favor the formation of straight polymer chains without crystalline grain boundaries, we have synthesized an amphiphilic conjugated polyelectrolyte, poly(fluorene-alt-thiophene) (PFT), which self-assembles in aqueous solutions to form cylindrical micelles. In contrast to many diblock copolymer assemblies, the semiconducting backbone runs parallel, not perpendicular, to the long axis of the cylindrical micelle. Solution-phase micelle formation is observed by X-ray and visible light scattering.
View Article and Find Full Text PDFLow band gap conjugated polymers with proper energy levels for charge transfer are required to achieve high-efficiency polymer solar cells. We report the synthesis and characterization of two new regioregular copolymers that are based on 3-alkoxythiophene monomers: poly(3-octylthiophene-2,5-diyl-co-3-decyloxythiophene-2,5-diyl) (POT-co-DOT) and poly{(9,9-dioctylfluorene)-2,7-diyl-alt-[4,7-bis(3-decyloxythien-2-yl)-2,1,3-benzothiadiazole]-5',5' '-diyl} (PF-co-DTB). Compared to the alkyl substituents, the alkoxy side chains on the thiophene units can effectively lower the band gap of copolymers and enhance the charge transfer to electron acceptors such as (6,6)-phenyl C(61)-butyric acid methyl ester (PCBM).
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