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1.
J Cell Physiol ; 239(1): 112-123, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38149778

RESUMEN

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.


Asunto(s)
Lisofosfolípidos , Osteogénesis , Receptores Lisofosfolípidos , Pérdida de Diente , Animales , Ratones , Diferenciación Celular/fisiología , Lisofosfolípidos/metabolismo , Osteoblastos/metabolismo , Ligamento Periodontal/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Receptores Lisofosfolípidos/metabolismo
2.
Cell Tissue Res ; 395(1): 53-62, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37985496

RESUMEN

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.


Asunto(s)
Proteínas Tirosina Fosfatasas Clase 3 Similares a Receptores , Diente , Animales , Ratones , Regulación del Desarrollo de la Expresión Génica , Morfogénesis , Odontogénesis , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Tirosina Fosfatasas Clase 3 Similares a Receptores/metabolismo , Transducción de Señal , Diente/metabolismo
3.
Proc Natl Acad Sci U S A ; 118(49)2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34845011

RESUMEN

Due to structural incommensurability, the emergence of a quasicrystal from a crystalline phase represents a challenge to computational physics. Here, the nucleation of quasicrystals is investigated by using an efficient computational method applied to a Landau free-energy functional. Specifically, transition pathways connecting different local minima of the Lifshitz-Petrich model are obtained by using the high-index saddle dynamics. Saddle points on these paths are identified as the critical nuclei of the 6-fold crystals and 12-fold quasicrystals. The results reveal that phase transitions between the crystalline and quasicrystalline phases could follow two possible pathways, corresponding to a one-stage phase transition and a two-stage phase transition involving a metastable lamellar quasicrystalline state, respectively.

4.
Ecotoxicol Environ Saf ; 283: 116786, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39083869

RESUMEN

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.

5.
J Asian Nat Prod Res ; 26(4): 489-496, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37642432

RESUMEN

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.


Asunto(s)
Acremonium , Acremonium/química , Estructura Molecular , Hongos , Staphylococcus aureus , Espectroscopía de Resonancia Magnética , Antibacterianos/química
6.
J Cell Physiol ; 238(7): 1520-1529, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37098720

RESUMEN

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.


Asunto(s)
N-Acetilglucosaminiltransferasas , Diente , Animales , Ratones , Apoptosis/fisiología , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , N-Acetilglucosaminiltransferasas/genética , N-Acetilglucosaminiltransferasas/metabolismo , Procesamiento Proteico-Postraduccional , Diente/crecimiento & desarrollo , Diente/metabolismo
7.
Langmuir ; 39(33): 11491-11509, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37535849

RESUMEN

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.

8.
Artículo en Inglés | MEDLINE | ID: mdl-37750753

RESUMEN

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).


Asunto(s)
Gammaproteobacteria , Rhodobacteraceae , Rhodophyta , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Composición de Base , Rhodobacteraceae/genética
9.
Respir Res ; 23(1): 110, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35509068

RESUMEN

BACKGROUND: Retinoid-related orphan receptor-α (RORα) and autophagy dysregulation are involved in the pathophysiology of chronic obstructive pulmonary disease (COPD), but little is known regarding their association. We investigated the role of RORα in COPD-related autophagy. METHODS: The lung tissues and cells from a mouse model were analyzed for autophagy markers by using western blot analysis and transmission electron microscopy. RESULTS: Cigarette smoke increased the LC3-II level and decreased the p62 level in whole lung homogenates of a chronic cigarette smoking mouse model. Although cigarette smoke did not affect the levels of p62 in Staggerer mutant mice (RORαsg/sg), the baseline expression levels of p62 were significantly higher than those in wild type (WT) mice. Autophagy was induced by cigarette smoke extract (CSE) in Beas-2B cells and in primary fibroblasts from WT mice. In contrast, fibroblasts from RORαsg/sg mice failed to show CSE-induced autophagy and exhibited fewer autophagosomes, lower LC3-II levels, and higher p62 levels than fibroblasts from WT mice. Damage-regulated autophagy modulator (DRAM), a p53-induced modulator of autophagy, was expressed at significantly lower levels in the fibroblasts from RORαsg/sg mice than in those from WT mice. DRAM knockdown using siRNA in Beas-2B cells inhibited CSE-induced autophagy and cell death. Furthermore, RORα co-immunoprecipitated with p53 and the interaction increased p53 reporter gene activity. CONCLUSIONS: Our findings suggest that RORα promotes autophagy and contributes to COPD pathogenesis via regulation of the RORα-p53-DRAM pathway.


Asunto(s)
Fumar Cigarrillos , Enfermedad Pulmonar Obstructiva Crónica , Animales , Autofagia , Fumar Cigarrillos/efectos adversos , Ratones , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Nicotiana , Proteína p53 Supresora de Tumor/efectos adversos
10.
Analyst ; 147(9): 1952-1960, 2022 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35403630

RESUMEN

Taking the hepatic sinusoid (HS) as the main delivery area of liver nutrients and metabolic waste, recognizing its structure is important for a deep understanding of liver function. In this paper, based on lycopersicon esculentum lectin (LEL), with targeting ability for endothelial cells, and carbon quantum dots (CQDs), with high biosafety, an LEL-coupled CQD immunofluorescence probe (CQD@LEL) that can label microvessels is designed and used for the fluorescence labeling and imaging of HS in liver tissue sections. The CQD size is approximately 2 nm. Blue fluorescence is emitted under excitation; its optimal excitation wavelength is 400 nm while the emission is at about 450 nm. Gel electrophoresis and capillary electrophoresis confirm that glutaraldehyde can couple LEL to CQD, and the obtained CQD@LEL retains the fluorescence property and has good stability. Optimization experiments show that its labeling effect is positively correlated with time and probe concentration for dyeing the blood vessels of mouse liver slices. In order to improve the effect further, a probe concentration of 0.17 mg mL-1 and incubation time of 3 h were chosen to label the liver tissue sections. The results show that the liver microvessels are formed by interstitial structures among the hepatic cords, and the HS presents a granular or patchy appearance. H&E and ultrathin section TEM show that the microvascular wall of the liver is composed of discontinuous endothelial cells, and there are Kupffer cells and other cells in the tubes, proving that our probe can clearly label the structure and morphology of liver microvessels. This work is of great significance for the visualization of HS.


Asunto(s)
Puntos Cuánticos , Animales , Capilares , Carbono/química , Colorantes , Células Endoteliales , Lectinas , Hígado , Ratones , Puntos Cuánticos/química
11.
Mol Biol Rep ; 49(6): 4461-4468, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35244868

RESUMEN

BACKGROUND: Wheat (Triticum aestivum L.) powdery mildew (Pm), which caused by Blumeria graminis f. sp. tritici (Bgt), is a destructive disease worldwide that causes severe yield losses in wheat. Resistant wheat cultivars easily lose their ability to effectively resist newly emerged Bgt strains; therefore, identifying new resistance genes is necessary for breeding resistant cultivars. METHODS AND RESULTS: Guizi 1 (GZ1) is a Chinese wheat cultivar with moderate and stable resistance to Pm. Genetic analysis indicated that the Pm resistance of GZ1 was controlled by a single dominant gene, designated PmGZ1. In total, 110 F2 individual plants and their 2 parents were subjected to genotyping by sequencing (GBS), which yielded 23,134 high-quality single-nucleotide polymorphisms (SNPs). The SNP distributions across the 21 chromosomes ranged from 134 on chromosome 6D to 6288 on chromosome 3B. Chromosome 6A has 1866 SNPs, among which 16 are physically located between positions 307,802,221 and 309,885,836 in an approximate 2.3-cM region; this region also had the greatest SNP density. The average map distance between SNP markers was 0.1 cM. A quantitative trait locus (QTL) with a significant epistatic effect on Pm resistance was mapped to chromosome 6A. The logarithm of odds (LOD) value of PmGZ1 was 34.8, and PmGZ1 was located within the confidence interval marked by chr6a-307802221 and chr6a-309885836. Moreover, 74.7% of the phenotypic variance was explained by PmGZ1. Four candidate genes (which encoded two TaAP2-A and two actin proteins) were annotated maybe as resistance genes. CONCLUSIONS: The present results provide valuable information for wheat genetic improvement, QTL fine mapping, and candidate gene validation.


Asunto(s)
Resistencia a la Enfermedad , Triticum , Ascomicetos , Resistencia a la Enfermedad/genética , Genes de Plantas/genética , Marcadores Genéticos , Genotipo , Fitomejoramiento , Enfermedades de las Plantas/genética , Triticum/genética
12.
Mol Biol Rep ; 49(8): 7455-7464, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35624389

RESUMEN

BACKGROUND: Stomata, which play important roles in both optimizing photosynthesis efficiency and adapting to stress, are closely related to IAA and ABA. In plants, the auxin influx carrier LAX3 has been found to play roles in development and stress tolerance. However, the function of LAX3 in stomata and in response to salt stress remains largely unknown. METHODS AND RESULTS: Here, we show that overexpression of wheat TaLAX3-1B in tobacco results in a decrease in stomatal aperture and a relatively closed state of the stomata. In addition, the stomatal movement of the OxTaLAX3-1B lines was less sensitive to ABA than that of the WT. Consistently, compared with the WT, the OxTaLAX3-1B lines showed significantly higher expression of stomate-, IAA- and ABA-related genes and endogenous IAA and ABA contents. Furthermore, compared with the WT, the OxTaLAX3-1B lines exhibited higher proline content, salt stress-related gene expression and ROS antioxidant enzyme activity but lower MDA content and ROS accumulation after salt treatment. CONCLUSIONS: The present results suggest that TaLAX3-1B plays a positive role in regulating stomatal closure and enhancing salt stress tolerance.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Nicotiana , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología , Sequías , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Estrés Salino/genética , Estrés Fisiológico/genética , Nicotiana/metabolismo
13.
Langenbecks Arch Surg ; 407(7): 3101-3106, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35732847

RESUMEN

PURPOSE: The totally extraperitoneal repair (TEP) technique has been widely performed, and compared with open surgery, TEP results in less postoperative pain and similar surgical outcomes in the treatment of inguinal hernias. However, TEP has a longer learning curve than does conventional surgery. METHODS: The data for patients who underwent TEP for inguinal hernias by a single surgeon between April 2017 and July 2019 were analyzed retrospectively. The cumulative summation (CUSUM) method and the following two variables were used to analyze the learning curve: (1) the operation event (OE), including intraoperative complications and conversion to open surgery; and (2) the operation score (OS), as calculated by the operation time, patient body mass index, and disease characteristics. RESULTS: The CUSUM chart showed three phases for both the OE and OS. The former reached a first inflection point after the 85th case and decreased after the 200th case, and the latter reached a plateau after the 101st case and decreased after the 203rd case. The operation time was longer in phases 1 and 2 than in phase 3 (64.2 min versus 47.9 min versus 31.1 min; p < 0.001), and the OS was lower in phase 3 than in the other phases (71.9 points versus 106.4 points versus 142.7 points; p < 0.001). Ten cases of intraoperative complications were observed, all in the first and second phases (p = 0.011). CONCLUSION: At least approximately 100 cases are required for the initial learning period, and an additional 103 cases are required for the accumulation of additional experience. Surgical competency can be gained after 203 TEPs are performed.


Asunto(s)
Hernia Inguinal , Laparoscopía , Humanos , Hernia Inguinal/cirugía , Curva de Aprendizaje , Herniorrafia/métodos , Estudios Retrospectivos , Laparoscopía/métodos , Complicaciones Intraoperatorias/cirugía , Resultado del Tratamiento
14.
Sensors (Basel) ; 22(22)2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36433225

RESUMEN

With the prevalence of degenerative diseases due to the increase in the aging population, we have encountered many spine-related disorders. Since the spine is a crucial part of the body, fast and accurate diagnosis is critically important. Generally, clinicians use X-ray images to diagnose the spine, but X-ray images are commonly occluded by the shadows of some bones, making it hard to identify the whole spine. Therefore, recently, various deep-learning-based spinal X-ray image analysis approaches have been proposed to help diagnose the spine. However, these approaches did not consider the characteristics of frequent occlusion in the X-ray image and the properties of the vertebra shape. Therefore, based on the X-ray image properties and vertebra shape, we present a novel landmark detection network specialized in lumbar X-ray images. The proposed network consists of two stages: The first step detects the centers of the lumbar vertebrae and the upper end plate of the first sacral vertebra (S1), and the second step detects the four corner points of each lumbar vertebra and two corner points of S1 from the image obtained in the first step. We used random spine cutout augmentation in the first step to robustify the network against the commonly obscured X-ray images. Furthermore, in the second step, we used CoordConv to make the network recognize the location distribution of landmarks and part affinity fields to understand the morphological features of the vertebrae, resulting in more accurate landmark detection. The proposed network was evaluated using 304 X-ray images, and it achieved 98.02% accuracy in center detection and 8.34% relative distance error in corner detection. This indicates that our network can detect spinal landmarks reliably enough to support radiologists in analyzing the lumbar X-ray images.


Asunto(s)
Vértebras Lumbares , Sacro , Vértebras Lumbares/diagnóstico por imagen , Sacro/diagnóstico por imagen , Rayos X , Pelvis , Radiografía
15.
Sensors (Basel) ; 22(18)2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-36146161

RESUMEN

For decades, co-relating different data domains to attain the maximum potential of machines has driven research, especially in neural networks. Similarly, text and visual data (images and videos) are two distinct data domains with extensive research in the past. Recently, using natural language to process 2D or 3D images and videos with the immense power of neural nets has witnessed a promising future. Despite the diverse range of remarkable work in this field, notably in the past few years, rapid improvements have also solved future challenges for researchers. Moreover, the connection between these two domains is mainly subjected to GAN, thus limiting the horizons of this field. This review analyzes Text-to-Image (T2I) synthesis as a broader picture, Text-guided Visual-output (T2Vo), with the primary goal being to highlight the gaps by proposing a more comprehensive taxonomy. We broadly categorize text-guided visual output into three main divisions and meaningful subdivisions by critically examining an extensive body of literature from top-tier computer vision venues and closely related fields, such as machine learning and human-computer interaction, aiming at state-of-the-art models with a comparative analysis. This study successively follows previous surveys on T2I, adding value by analogously evaluating the diverse range of existing methods, including different generative models, several types of visual output, critical examination of various approaches, and highlighting the shortcomings, suggesting the future direction of research.


Asunto(s)
Aprendizaje Automático , Redes Neurales de la Computación , Humanos , Imagenología Tridimensional , Percepción Visual
16.
Zhongguo Zhong Yao Za Zhi ; 47(24): 6560-6572, 2022 Dec.
Artículo en Zh | MEDLINE | ID: mdl-36604904

RESUMEN

Triterpenes, with high diversity and a wide range of sources, can be found in many medicinal plants. They have been found free or as glycosides/esters by combining with sugars. Most of them act as signaling molecules and function in stress response. They are also the material basis for the therapeutic effect of various medicinal plants. Modern pharmacological research has shown that they have the anti-inflammatory, antibacterial, antiviral, anti-tumor, fertility-regulating, and immunomodulatory effects. They top plant natural products in both quantity and diversity, and among them, tetrachyclic triterpenes and pentachyclic triterpenes are most abundant. The first step of the structural diversification is the cyclization 2,3-oxidosqualene, which is catalyzed by oxidosqualene cyclases(OSCs). Numerous OSCs exist, each with a specific cyclization mechanism, and thus over 100 different cyclic triterpene skeletons have been found in nature. This study reviewed the research on the biosynthetic pathways of triterpenes in medicinal plants, regulatory mechanisms of the pathways, and the key enzymes, and analyzed the expression regulation and structural characteristics of key enzyme genes involved in the synthetic pathways. This study is expected to serve as a reference for further research on triterpenes, such as the directional regulation of metabolic flow and heterologous biosynthesis and lay a basis for the regulation of triterpene synthesis and the selection of high-quality germplasm. This study also provides basic materials for further research and development of triterpenes from medicinal plants.


Asunto(s)
Vías Biosintéticas , Plantas Medicinales , Triterpenos , Plantas Medicinales/química , Plantas Medicinales/genética , Triterpenos/química
17.
J Periodontal Res ; 56(4): 735-745, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33682929

RESUMEN

OBJECTIVE: To evaluate the effect of resveratrol on periodontal bone regeneration after local delivery and to determine its effect on inflammatory mediators. BACKGROUND: Resveratrol is considered an anti-inflammatory polyphenolic stilbene involved in the modulation of inflammation. MATERIALS AND METHODS: Periodontitis was induced in mouse molars using a 5-day ligature model followed by the left second molar extraction and 50 µM resveratrol treatment for 1 and 2 weeks. We then examined specimens treated for 1 week histologically and with immunostaining. Microfocus-computed tomography (micro-CT) was used to examine the bone volume formation. RESULTS: After 1 week of treatment, proinflammatory cytokine levels (TNF-alpha and IL6), cells exhibiting neutrophil and macrophage marker (MPO), cell proliferation marker (Ki67), and preosteoblastic marker (RUNX2) reactivity decreased in the resveratrol-treated specimens compared to the control group. In contrast, we observed a higher number of CD31-, F4/80-, and osteocalcin- (OCN-) positive cells in the resveratrol-treated specimens. After 2 weeks, micro-CT confirmed an increased bone mass in the region of the extraction socket in the resveratrol-treated group. CONCLUSION: After 1 week, the resveratrol-treated specimens revealed evidence of inflammation modulation compared to the control group. These data suggest that resveratrol not only affects inflammation control but also is useful for treating periodontitis-related tissue defects and bone regeneration.


Asunto(s)
Pérdida de Hueso Alveolar , Periodontitis , Pérdida de Hueso Alveolar/diagnóstico por imagen , Pérdida de Hueso Alveolar/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Inflamación/tratamiento farmacológico , Ratones , Osteogénesis , Periodontitis/diagnóstico por imagen , Periodontitis/tratamiento farmacológico , Resveratrol
18.
Proc Natl Acad Sci U S A ; 115(5): 847-854, 2018 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-29348199

RESUMEN

Cooling disordered compositionally asymmetric diblock copolymers leads to the formation of nearly spherical particles, each containing hundreds of molecules, which crystallize upon cooling below the order-disorder transition temperature (TODT). Self-consistent field theory (SCFT) reveals that dispersity in the block degrees of polymerization stabilizes various Frank-Kasper phases, including the C14 and C15 Laves phases, which have been accessed experimentally in low-molar-mass poly(isoprene)-b-poly(lactide) (PI-PLA) diblock copolymers using thermal processing strategies. Heating and cooling a specimen containing 15% PLA above and below the TODT from the body-centered cubic (BCC) or C14 states regenerates the same crystalline order established at lower temperatures. This memory effect is also demonstrated with a specimen containing 20% PLA, which recrystallizes to either C15 or hexagonally ordered cylinders (HEXC) upon heating and cooling. The process-path-dependent formation of crystalline order shapes the number of particles per unit volume, n/V, which is retained in the highly structured disordered liquid as revealed by small-angle X-ray scattering (SAXS) experiments. We hypothesize that symmetry breaking during crystallization is governed by the particle number density imprinted in the liquid during ordering at lower temperature, and this metastable liquid is kinetically constrained from equilibrating due to prohibitively large free energy barriers for micelle fusion and fission. Ordering at fixed n/V is enabled by facile chain exchange, which redistributes mass as required to meet the multiple particle sizes and packing associated with specific low-symmetry Frank-Kasper phases. This discovery exposes universal concepts related to order and disorder in self-assembled soft materials.

19.
J Asian Nat Prod Res ; 23(2): 117-122, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31979983

RESUMEN

Two new compounds named asperpenes D (1) and E (2) were isolated from the marine-derived fungus Aspergillus sp. SCS-KFD66. Their structures were determined on the basis of spectroscopic methods. Compound 2 represents the first natural product bearing a 2-substituted-5-oxo-4-phenyl-2,5-dihydrofuran-3-carboxylic acid skeleton. All the compounds were tested for enzyme inhibitory activity against AChE and α-glucosidase and DPPH radical scavenging activity, respectively. [Formula: see text].


Asunto(s)
Productos Biológicos , Bivalvos , Animales , Aspergillus , Estructura Molecular , alfa-Glucosidasas
20.
Electrophoresis ; 41(18-19): 1606-1616, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32557720

RESUMEN

Chuanxiong Rhizoma is a commonly used in traditional Chinese medicine. Chuanxiong Rhizoma is widely distributed in Sichuan province, China, including the cities of Dujiangyan, Pengzhou, Meishan, Qionglai, and Shifang. However, reports on the comparisons of quality of Chuanxiong Rhizoma of different production origins are limited. Therefore, an ultra-HPLC with triple quadrupole MS method was developed for the determination of 20 bioactive components (12 aromatic acids and eight phthalides) in 36 samples from different production origins and further assessed its quality. The contents of these 20 constituents of samples were analyzed by hierarchical cluster analysis and orthogonal partial least squares discrimination analysis; the result indicated that Chuanxiong Rhizoma of different production origins had some differences. Thirteen constituents of quality difference markers were acquired by variable importance for the project. Furthermore, the sum of the contents of these quality difference markers was different from various production origins of Chuanxiong Rhizoma. Meanwhile, Z-ligustilide and senkyunolide A as main constituents of quality difference markers, the rate of various production origins of Chuanxiong Rhizoma was different. This study provides a foundation for the quality assessment of Chuanxiong Rhizoma.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/análisis , Benzofuranos/análisis , China , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/clasificación , Geografía , Límite de Detección , Modelos Lineales , Análisis Multivariante , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos
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