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1.
Macromolecules ; 57(15): 7087-7097, 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39156194

ABSTRACT

This work aims to systematically examine the topology effect on the self-assembly of block copolymers. Compositionally, symmetric polystyrene-block-polydimethylsiloxane block copolymers (BCPs) with different chain topologies (diblock, three-arm star-block, and four-arm star-block) and various molecular weights are synthesized. These purposely designed block copolymers are used as a model system to investigate the topology effect on order-to-disorder transition temperature (T ODT) by temperature-resolved small-angle X-ray scattering experiments. An increase of the T ODT is observed when the arm number of BCPs with equivalent arm length (i.e., molecular weight) is increased from one to four. Based on the random-phase approximation (RPA), Flory-Huggins interaction parameter (χ) is determined from the regression of the measured T ODT. The observation by differential scanning calorimetry also demonstrates the shifting of the endothermic peak from the order-to-disorder transition of star-blocks to the higher temperature region, consistent with the scattering experiments and the RPA prediction.

2.
J Am Chem Soc ; 146(32): 22661-22674, 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39099104

ABSTRACT

Synthesizing anisotropic polymeric nanoparticles (NPs) with well-defined shapes, dimensions, and molecular orientations is a very challenging task. Herein, we report the synthesis of surprisingly highly uniform shape-anisotropic polymer NPs with uniaxial internal molecular orientation. Keys to our method are synchronized polymerization and self-assembly (SPSA), which can even be realized by regular dispersion polymerization. This is demonstrated using a monomer containing a rigid 4-nitroazobenzene (NAB) side group. The short nucleation period, the completion of microphase separation before molecular motion is frozen, and sufficient low particle/solvent interfacial tension are shown to be the origins of the highly uniform dimensions, single liquid crystal domains, and well-defined anisotropic shape of particles. The liquid crystallization ability of the polymers, control of molecular weight distribution, and the polymerization kinetics are identified as three key factors controlling the NP formation. The uniformity of these NPs facilitates their SA formation into colloidal crystals. The particles exhibit optically anisotropic properties depending on orientations and, in particular, show intriguing photoswitchable LC-glass (order-disorder) transition, which can be used for the detection of ultraviolet (UV) light and allows the fabrication of photoreversible colloidal films.

3.
ACS Appl Mater Interfaces ; 16(30): 40263-40274, 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39036947

ABSTRACT

This study aims to develop a strategy for the fabrication of multilayer nanopatterns through sequential self-assembly of lamella-forming polystyrene-block-polydimethylsiloxane (PS-b-PDMS) block copolymer (BCP) from solvent annealing. By simply tuning the solvent selectivity, a variety of self-assembled BCP thin-film morphologies, including hexagonal perforated lamellae (HPL), parallel cylinders, and spheres, can be obtained from single-composition PS-b-PDMS. By taking advantage of reactive ion etching (RIE), topographic SiO2 monoliths with well-ordered arrays of hexagonally packed holes, parallel lines, and hexagonally packed dots can be formed. Subsequently, hole-on-dot and line-on-hole hierarchical textures can be created through a layer-by-layer process with RIE treatment as evidenced experimentally and confirmed theoretically. The results demonstrated the feasibility of creating three-dimensional (3D) nanopatterning from the sequential self-assembly of single-composition PS-b-PDMS via solvent annealing, providing an appealing process for nano-MEMS manufacturing based on BCP lithography.

4.
Ecotoxicol Environ Saf ; 283: 116786, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-39083869

ABSTRACT

Cd ions are absorbed and transported from the soil by crop roots, which are the first organ to be exposed to Cd. This results in an increase in cadmium ions in crops, significantly affecting crop growth and yield. Exogenous melatonin (MT) can help reduce cadmium (Cd) stress in cotton, but the specific contribution of roots to this process remains unclear. In order to address this knowledge gap, an in-situ root phenotyping study was conducted to investigate the the phenotype and lifespan of roots under cadmium stress (Cd) and melatonin treatment (Cd + MT). The results showed that MT alleviated the decreases in plant height, leaf area, SPAD value, stem diameter, stomatal conductance and net photosynthetic rate under Cd stress, which further promoted the biomass accumulation in various cotton organs. What is more, the Cd + MT treatment increased root volume, surface area, and length under Cd stress by 25.63 %, 10.58 %, and 21.89 %, respectively, compared with Cd treatment. Interestingly, compared to Cd treatment, Cd + MT treatment also significantly extended the lifespan of roots and root hairs by 6.68 days and 2.18 days, respectively. In addition, Cd + MT treatment reduced the transport of Cd from roots to shoots, particularly to bolls, and decreased the Cd bioconcentration factor in bolls by 61.17 %, compared to Cd treatment. In conclusion, these findings show that applying MT externally helps reduce Cd stress by delaying root senescence, promoting root development and regulating Cd transport. This method can be an effective approach to managing Cd stress in cotton.


Subject(s)
Cadmium , Gossypium , Melatonin , Plant Roots , Soil Pollutants , Gossypium/drug effects , Gossypium/growth & development , Melatonin/pharmacology , Cadmium/toxicity , Plant Roots/drug effects , Plant Roots/growth & development , Soil Pollutants/toxicity , Biological Transport/drug effects
5.
ACS Nano ; 18(23): 14791-14840, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38814908

ABSTRACT

We explore the potential of nanocrystals (a term used equivalently to nanoparticles) as building blocks for nanomaterials, and the current advances and open challenges for fundamental science developments and applications. Nanocrystal assemblies are inherently multiscale, and the generation of revolutionary material properties requires a precise understanding of the relationship between structure and function, the former being determined by classical effects and the latter often by quantum effects. With an emphasis on theory and computation, we discuss challenges that hamper current assembly strategies and to what extent nanocrystal assemblies represent thermodynamic equilibrium or kinetically trapped metastable states. We also examine dynamic effects and optimization of assembly protocols. Finally, we discuss promising material functions and examples of their realization with nanocrystal assemblies.

6.
Front Cell Dev Biol ; 12: 1369634, 2024.
Article in English | MEDLINE | ID: mdl-38756696

ABSTRACT

Introduction: Prohibitin (PHB) is an essential scaffold protein that modulates signaling pathways controlling cell survival, metabolism, inflammation, and bone formation. However, its specific role in periodontium development remains less understood. This study aims to elucidate the expression pattern and function of PHB in periodontium development and its involvement in alveolar bone formation. Methods: Immunolocalization of PHB in the periodontium of postnatal (PN) mice were examined. Phb morpholino was micro-injected into the right-side mandible at PN5, corresponding to the position where the alveolar bone process forms in relation to the lower first molar. The micro-injection with a scramble control (PF-127) and the left-side mandibles were used as control groups. Five days post-micro-injection, immunohistochemical analysis and micro-CT evaluation were conducted to assess bone mass and morphological changes. Additionally, expression patterns of signaling molecules were examined following Phb downregulation using 24-h in vitro cultivation of developing dental mesenchyme at E14.5. Results: The immunostaining of PHB showed its localization in the periodontium at PN5, PN8, and PN10. The in vitro cultivation of dental mesenchyme resulted in alterations in Bmps, Runx2, and Wnt signalings after Phb knock-down. At 5 days post-micro-injection, Phb knocking down showed weak immunolocalizations of runt-related transcription factor (RUNX2) and osteocalcin (OCN). However, knocking down Phb led to histological alterations characterized by decreased bone mass and stronger localizations of Ki67 and PERIOSTIN in the periodontium compared 1 to control groups. The micro-CT evaluation showed decreased bone volume and increased PDL space in the Phb knock-down specimens, suggesting its regulatory role in bone formation. Discussion: The region-specific localization of PHB in the margin where alveolar bone forms suggests its involvement in alveolar bone formation and the differentiation of the periodontal ligament. Overall, our findings suggest that Phb plays a modulatory role in alveolar bone formation by harmoniously regulating bone-forming-related signaling molecules during periodontium development.

7.
Anim Cells Syst (Seoul) ; 28(1): 272-282, 2024.
Article in English | MEDLINE | ID: mdl-38741948

ABSTRACT

Unlike vertebrates, the number of toothed taxa in invertebrates is very few, with leeches being the only tooth-bearing organisms in the phylum Annelida. Copious studies have been conducted regarding vertebrate teeth; however, studies regarding the structure and function of invertebrate teeth are limited. In this study, the tooth structure of leeches, specifically Hirudo nipponia and Haemadipsa rjukjuana, was revealed, which showed sharp and pointed teeth along the apex of three jaws. Understanding conserved signaling regulations among analogous organs is crucial for uncovering the underlying mechanisms during organogenesis. Therefore, to shed light on the evolutionary perspective of odontogenesis to some extent, we conducted de novo transcriptome analyses using embryonic mouse tooth germs, Hirudo teeth, and Helobdella proboscises to identify conserved signaling molecules involved in tooth development. The selection criteria were particularly based on the presence of tooth-related genes in mice, Hirudo teeth, and Helobdella proboscis, wherein 4113 genes were commonly expressed in all three specimens. Furthermore, the chemical nature of leech teeth was also examined via TEM-EDS to compare the chemical composition with vertebrate teeth. The examination of tissue-specific genetic information and chemical nature between leeches and mice revealed chemical similarities between leech and mice teeth, as well as conserved signaling molecules involved in tooth formation, including Ptpro, Prickle2, and Wnt16. Based on our findings, we propose that leech teeth express signaling molecules conserved in mice and these conserved tooth-specific signaling for dental hard tissue formation in mice would corresponds to the structural formation of the toothed jaw in leeches.

8.
J Asian Nat Prod Res ; 26(4): 489-496, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37642432

ABSTRACT

Two new compounds named 3(S)-hydroxy-1-(2,4,5-trihydroxy-3,6- dimethylphenyl)-hex-4E-en-1-one (1) and acremonilactone (2), together with nine known compounds (3-11), were isolated from the fermentation broth of Acremonium sp. associated with marine sediments collected from South China Sea. NMR and HRESIMS spectroscopic analysis elucidated the structure of two new compounds. Compound 2 had characteristic rotary gate shape skeleton with a six-membered lactone. Compounds 1 and 9 showed DPPH radical scavenging activity with inhibition rates of 96.50 and 85.95% at the concentration of 0.5 mg/ml, respectively. Moreover, compounds 4, 6 and 11 showed definite antibacterial activity against Staphylococcus aureus ATCC 6538.


Subject(s)
Acremonium , Acremonium/chemistry , Molecular Structure , Fungi , Staphylococcus aureus , Magnetic Resonance Spectroscopy , Anti-Bacterial Agents/chemistry
9.
Pathol Res Pract ; 253: 155000, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38091885

ABSTRACT

StAR-related lipid transfer domain protein 8 (STARD8), encoding a Rho-GTPase-activating protein, and WNK2, encoding a serine/threonine kinase are candidate tumor suppressor genes (TSGs) in human cancers. Inactivation of these genes that would promote cancer pathogenesis is largely unknown in colon cancer (CC). Our study addressed to address whether STARD8 and WNK2 genes are mutated in CC. STARD8 and WNK2 genes possess mononucleotide repeats in their exons, which could be the targets for frameshift mutations in cancers with high microsatellite instability (MSI-H). By single-strand conformation polymorphism (SSCP) analysis, we analyzed the repeated sequences in 140 CCs (95 CCs with MSI-H and 45 CCs with stable MSI (MSS)). By DNA sequencing, we found that five MSI-H CCs (5/95: 5.3%) harbored the frameshift mutations, whereas MSS CCs (0/45) did not. In addition, we detected regional heterogeneous frameshift mutations of these genes in four (25%) of 16 MSI-H CCs. In immunohistochemistry for WNK2, WNK2 expression in the MSI-H CCs was significantly lower than that in the MSS CCs. Our results for the mutation and expression indicate that STARD8 and WNK2 genes are altered at various levels (frameshift mutation, expression, and regional heterogeneity) in MSI-H CCs, which might play a role in the pathogenesis by inactivating their TSG functions.


Subject(s)
Colonic Neoplasms , Colorectal Neoplasms , Stomach Neoplasms , Humans , Colorectal Neoplasms/pathology , DNA Mutational Analysis/methods , Stomach Neoplasms/pathology , Mutation/genetics , Colonic Neoplasms/genetics , Frameshift Mutation , Microsatellite Instability , Genes, Tumor Suppressor , Microsatellite Repeats , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism
10.
Cell Tissue Res ; 395(1): 53-62, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37985496

ABSTRACT

Glomerular epithelial protein-1 (Glepp1), a R3 subtype family of receptor-type protein tyrosine phosphatases, plays important role in the activation of Src family kinases and regulates cellular processes such as cell proliferation, differentiation, and apoptosis. In this study, we firstly examined the functional evaluation of Glepp1 in tooth development and morphogenesis. The precise expression level and developmental function of Glepp1 were examined by RT-qPCR, in situ hybridization, and loss and gain of functional study using a range of in vitro organ cultivation methods. Expression of Glepp1 was detected in the developing tooth germs in cap and bell stage of tooth development. Knocking down Glepp1 at E13 for 2 days showed the altered expression levels of tooth development-related signaling molecules, including Bmps, Dspp, Fgf4, Lef1, and Shh. Moreover, transient knock down of Glepp1 revealed alterations in cellular physiology, examined by the localization patterns of Ki67 and E-cadherin. Similarly, knocking down of Glepp1 showed disrupted enamel rod and interrod formation in 3-week renal transplanted teeth. In addition, due to attrition of odontoblastic layers, the expression signals of Dspp and the localization of NESTIN were almost not detected after knock down of Glepp1; however, their expressions were increased after Glepp1 overexpression. Thus, our results suggested that Glepp1 plays modulating roles during odontogenesis by regulating the expression levels of signaling molecules and cellular events to achieve the proper structural formation of hard tissue matrices in mice molar development.


Subject(s)
Receptor-Like Protein Tyrosine Phosphatases, Class 3 , Tooth , Animals , Mice , Gene Expression Regulation, Developmental , Morphogenesis , Odontogenesis , Protein Tyrosine Phosphatases/metabolism , Receptor-Like Protein Tyrosine Phosphatases, Class 3/metabolism , Signal Transduction , Tooth/metabolism
11.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1020529

ABSTRACT

Surgical operation is the main treatment of oral and maxillofacial tumors.Dysphagia is a common postoperative complication.Swal-lowing disorder can not only lead to mis-aspiration,malnutrition,aspiration pneumonia and other serious consequences,but also may cause psychological problems and social communication barriers,affecting the quality of life of the patients.At present,there is no systematic evalua-tion and rehabilitation management plan for the problem of swallowing disorder after oral and maxillofacial tumor surgery in China.Combining the characteristics of postoperative swallowing disorder in patients with oral and maxillofacial tumors,summarizing the clinical experience of ex-perts in the field of tumor and rehabilitation,reviewing and summarizing relevant literature at home and abroad,and through joint discussion and modification,a group of national experts reached this consensus including the core contents of the screening of swallowing disorders,the phased assessment of prognosis and complications,and the implementation plan of comprehensive management such as nutrition management,respiratory management,swallowing function recovery,psychology and nursing during rehabilitation treatment,in order to improve the evalua-tion and rehabilitation of swallowing disorder after oral and maxillofacial tumor surgery in clinic.

12.
Intestinal Research ; : 213-249, 2024.
Article in English | WPRIM (Western Pacific) | ID: wpr-1043131

ABSTRACT

Ulcerative colitis (UC) is a chronic inflammation of the gastrointestinal tract and is characterized by alternating periods of inflammation and remission. Although UC incidence is lower in Taiwan than in Western countries, its impact remains considerable, demanding updated guidelines for addressing local healthcare challenges and patient needs. The revised guidelines employ international standards and recent research, emphasizing practical implementation within the Taiwanese healthcare system. Since the inception of the guidelines in 2017, the Taiwan Society of Inflammatory Bowel Disease has acknowledged the need for ongoing revisions to incorporate emerging therapeutic options and evolving disease management practices. This updated guideline aims to align UC management with local contexts, ensuring comprehensive and context-specific recommendations, thereby raising the standard of care for UC patients in Taiwan. By adapting and optimizing international protocols for local relevance, these efforts seek to enhance health outcomes for patients with UC.

13.
Intestinal Research ; : 250-285, 2024.
Article in English | WPRIM (Western Pacific) | ID: wpr-1043132

ABSTRACT

Crohn’s disease (CD) is a chronic, fluctuating inflammatory condition that primarily affects the gastrointestinal tract. Although the incidence of CD in Taiwan is lower than that in Western countries, the severity of CD presentation appears to be similar between Asia and the West. This observation indicates the urgency for devising revised guidelines tailored to the unique reimbursement system, and patient requirements in Taiwan. The core objectives of these updated guidelines include the updated treatment choices and the integration of the treat-to-target strategy into CD management, promoting the achievement of deep remission to mitigate complications and enhance the overall quality of life. Given the diversity in disease prevalence, severity, insurance policies, and access to medical treatments in Taiwan, a customized approach is imperative for formulating these guidelines. Such tailored strategies ensure that international standards are not only adapted but also optimized to local contexts. Since the inception of its initial guidelines in 2017, the Taiwan Society of Inflammatory Bowel Disease (TSIBD) has acknowledged the importance of continuous revisions for incorporating new therapeutic options and evolving disease management practices. The latest update leverages international standards and recent research findings focused on practical implementation within the Taiwanese healthcare system.

14.
J Cell Physiol ; 239(1): 112-123, 2024 01.
Article in English | MEDLINE | ID: mdl-38149778

ABSTRACT

Lipid biosynthesis is recently studied its functions in a range of cellular physiology including differentiation and regeneration. However, it still remains to be elucidated in its precise function. To reveal this, we evaluated the roles of lysophosphatidic acid (LPA) signaling in alveolar bone formation using the LPA type 2 receptor (LPAR2) antagonist AMG-35 (Amgen Compound 35) using tooth loss without periodontal disease model which would be caused by trauma and usually requires a dental implant to restore masticatory function. In this study, in vitro cell culture experiments in osteoblasts and periodontal ligament fibroblasts revealed cell type-specific responses, with AMG-35 modulating osteogenic differentiation in osteoblasts in vitro. To confirm the in vivo results, we employed a mouse model of tooth loss without periodontal disease. Five to 10 days after tooth extraction, AMG-35 facilitated bone formation in the tooth root socket as measured by immunohistochemistry for differentiation markers KI67, Osteocalcin, Periostin, RUNX2, transforming growth factor beta 1 (TGF-ß1) and SMAD2/3. The increased expression and the localization of these proteins suggest that AMG-35 elicits osteoblast differentiation through TGF-ß1 and SMAD2/3 signaling. These results indicate that LPAR2/TGF-ß1/SMAD2/3 represents a new signaling pathway in alveolar bone formation and that local application of AMG-35 in traumatic tooth loss can be used to facilitate bone regeneration and healing for further clinical treatment.


Subject(s)
Lysophospholipids , Osteogenesis , Receptors, Lysophospholipid , Tooth Loss , Animals , Mice , Cell Differentiation/physiology , Lysophospholipids/metabolism , Osteoblasts/metabolism , Periodontal Ligament/metabolism , Transforming Growth Factor beta1/metabolism , Receptors, Lysophospholipid/metabolism
15.
Res Sq ; 2023 Nov 28.
Article in English | MEDLINE | ID: mdl-38077066

ABSTRACT

Burgeoning evidence demonstrates that effects of environmental exposures can be transmitted to subsequent generations through the germline without DNA mutations1,2. This phenomenon remains controversial because underlying mechanisms have not been identified. Therefore, understanding how effects of environmental exposures are transmitted to unexposed generations without DNA mutations is a fundamental unanswered question in biology. Here, we used an established murine model of male-specific transgenerational obesity to show that exposure to the obesogen tributyltin (TBT) elicited heritable changes in chromatin interactions (CIs) in primordial germ cells (PGCs). New CIs were formed within the Ide gene encoding Insulin Degrading Enzyme in the directly exposed PGCs, then stably maintained in PGCs of the subsequent (unexposed) two generations. Concomitantly, Ide mRNA expression was decreased in livers of male descendants from the exposed dams. These males were hyperinsulinemic and hyperglycemic, phenocopying Ide-deficient mice that are predisposed to adult-onset, diet-induced obesity. Creation of new CIs in PGCs, suppression of hepatic Ide mRNA, increased fat mass, hyperinsulinemia and hyperglycemia were male-specific. Our results provide a plausible molecular mechanism underlying transmission of the transgenerational predisposition to obesity caused by gestational exposure to an environmental obesogen. They also provide an entry point for future studies aimed at understanding how environmental exposures alter chromatin structure to influence physiology across multiple generations in mammals.

16.
iScience ; 26(11): 108329, 2023 Nov 17.
Article in English | MEDLINE | ID: mdl-38026217

ABSTRACT

Passion fruit, a valuable tropical fruit, faces climate-related growth challenges. Antioxidant enzymes are vital for both stress protection and growth regulation in plants. We first provided systemic analysis of enzymatic antioxidant gene families in passion fruit, identifying 90 members including 11 PeSODs, 45 PeAPXs, 8 PeCATs, 7 PeGPXs, 6 PeMDHARs, 8 PeDHARs, and 5 PeGRs. Gene members in each gene family with same subcellular localization showed closer phylogenetic relationship. Many antioxidant genes exhibited tissue- or developmental stage-specific expression patterns during floral and fruit development, with some widely expressed. Their co-expressed genes were linked to photosynthesis and energy metabolism, suggesting roles in protecting highly proliferating tissues from oxidative damage. Potential genes for enhancing temperature stress resistance were identified. The involvement of diverse regulatory factors including miRNAs, transcription factors, and CREs might contribute to the complex roles of antioxidant genes. This study informs future research on antioxidant genes and passion fruit breeding.

17.
Article in English | MEDLINE | ID: mdl-37750753

ABSTRACT

A Gram-negative, pale yellow-pigmented, non-flagellated, motile, rod-shaped and aerobic bacterium, designated strain PG104T, was isolated from red algae Grateloupia sp. collected from the coastal area of Pohang, Republic of Korea. Growth of strain PG104T was observed at 15-35 °C (optimum, 30 °C), pH 6.0-10.0 (optimum, pH 7.5-8.0) and in the presence of 0-8.0 % (w/v) NaCl (optimum, 5.0 %). The predominant fatty acids included C17 : 0, C18 : 0, 11-methyl C18 : 1 ω7c and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and the major respiratory quinone was Q-10. Polar lipids included phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified lipid and one unidentified aminolipid. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain PG104T formed a phylogenetic lineage with members of the genus Falsirhodobacter and exhibited 16S rRNA gene sequence similarities of 97.1 and 96.6 % to Falsirhodobacter deserti W402T and Falsirhodobacter halotolerans JA744T, respectively. The complete genome of strain PG104T consisted of a single circular chromosome of approximately 2.8 Mbp with five plasmids. Based on polyphasic taxonomic data, strain PG104T represents a novel species in the genus Falsirhodobacter, for which the name Falsirhodobacter algicola sp. nov. is proposed. The type strain of Falsirhodobacter algicola is PG104T (=KCTC 82230T=JCM 34380T).


Subject(s)
Gammaproteobacteria , Rhodobacteraceae , Rhodophyta , Fatty Acids/chemistry , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , DNA, Bacterial/genetics , Bacterial Typing Techniques , Base Composition , Rhodobacteraceae/genetics
18.
Langmuir ; 39(33): 11491-11509, 2023 Aug 22.
Article in English | MEDLINE | ID: mdl-37535849

ABSTRACT

The phase behavior of binary blends of diblock copolymers has been examined extensively in the past decades. Experimental and theoretical studies have demonstrated that mixing two different block copolymers provides an efficient and versatile route to regulate their self-assembled morphologies. A good understanding of the principles governing the self-assembly of block copolymer blends has been obtained from the study of A1B1/A2B2 diblock copolymer blends. The second (A2B2) diblocks could act synergistically as fillers and cosurfactants to regulate the domain size and interfacial properties, resulting in the formation of ordered phases not found in the parent (A1B1 or A2B2) diblock copolymer melts. The study of A1B1/A2B2 block copolymer blends further provides a solid foundation for future research on more complex block copolymer blends.

19.
Anal Chim Acta ; 1260: 341210, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-37121658

ABSTRACT

The targeted labeling imaging of stellate cells on liver frozen section by immunofluorescence is a very promising visualization technique to study the distribution of stellate cells in the liver. In this study, water soluble carbon quantum dots that can emit blue, green and yellow fluorescence are synthesized by the hydrothermal method, and their sizes are 3.2, 3.7, and 4.3 nm, respectively. The three carbon quantum dots have good fluorescence stability, and the quantum yields are 36.1%, 26.3% and 21%, respectively. When the mass fraction of KCl in the blue carbon quantum dot dispersion system is 13%, it still maintains the liquid state at -30 °C. The final fluorescent probe is obtained after the carbon quantum dots are coupled with the secondary antibody, spectral characterizations confirm that the conjugate probe still maintains protein immunoactivity and has good stability. Cell experiments prove that the probe has good biocompatibility, the rabbit anti-mouse Desmin antibody is used as the primary antibody, the results of cellular immunofluorescence imaging and flow cytometry show that the probe can specifically label hepatic stellate cell at -20 °C. The results of liver frozen section experiments show that hepatic stellate cell can be specifically targeted and labeled by the fluorescent probe. This labeling technology provides an important technical means for elucidating the structure and function of the liver at the cellular level, exploring the liver pathological change, and designing and developing drug.


Subject(s)
Quantum Dots , Animals , Rabbits , Fluorescent Dyes/toxicity , Fluorescent Dyes/chemistry , Frozen Sections , Carbon/chemistry , Freezing , Liver/diagnostic imaging
20.
J Cell Physiol ; 238(7): 1520-1529, 2023 07.
Article in English | MEDLINE | ID: mdl-37098720

ABSTRACT

To understand the mechanisms underlying tooth morphogenesis, we examined the developmental roles of important posttranslational modification, O-GlcNAcylation, which regulates protein stability and activity by the addition and removal of a single sugar (O-GlcNAc) to the serine or threonine residue of the intracellular proteins. Tissue and developmental stage-specific immunostaining results against O-GlcNAc and O-GlcNAc transferase (OGT) in developing tooth germs would suggest that O-GlcNAcylation is involved in tooth morphogenesis, particularly in the cap and secretory stage. To evaluate the developmental function of OGT-mediated O-GlcNAcylation, we employed an in vitro tooth germ culture method at E14.5, cap stage before secretory stage, for 1 and 2 days, with or without OSMI-1, a small molecule OGT inhibitor. To examine the mineralization levels and morphological changes, we performed renal capsule transplantation for one and three weeks after 2 days of in vitro culture at E14.5 with OSMI-1 treatment. After OGT inhibition, morphological and molecular alterations were examined using histology, immunohistochemistry, real-time quantitative polymerase chain reaction, in situ hybridization, scanning electron microscopy, and ground sectioning. Overall, inhibition of OGT resulted in altered cellular physiology, including proliferation, apoptosis, and epithelial rearrangements, with significant changes in the expression patterns of ß-catenin, fibroblast growth factor 4 (fgf4), and sonic hedgehog (Shh). Moreover, renal capsule transplantation and immunolocalizations of Amelogenin and Nestin results revealed that OGT-inhibited tooth germs at cap stage exhibited with structural changes in cuspal morphogenesis, amelogenesis, and dentinogenesis of the mineralized tooth. Overall, we suggest that OGT-mediated O-GlcNAcylation regulates cell signaling and physiology in primary enamel knot during tooth development, thus playing an important role in mouse molar morphogenesis.


Subject(s)
N-Acetylglucosaminyltransferases , Tooth , Animals , Mice , Apoptosis/physiology , Hedgehog Proteins/genetics , Hedgehog Proteins/metabolism , N-Acetylglucosaminyltransferases/genetics , N-Acetylglucosaminyltransferases/metabolism , Protein Processing, Post-Translational , Tooth/growth & development , Tooth/metabolism
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