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1.
Plant J ; 114(2): 437-454, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36786687

RESUMO

Drought is a major abiotic stress reducing maize (Zea mays) yield worldwide especially before and during silking. The mechanism underlying drought tolerance in maize and the roles of different organs have not been elucidated. Hence, we conducted field trials under pre-silking drought conditions using two maize genotypes: FM985 (drought-tolerant) and ZD958 (drought-sensitive). The two genotypes did not differ in plant height, grain number, and yield under control conditions. However, the grain number per ear and the yield of FM985 were 38.1 and 35.1% higher and plants were 17.6% shorter than ZD958 under drought conditions. More 13 C photosynthates were transported to the ear in FM985 than in ZD958, which increased floret fertility and grain number. The number of differentially expressed genes was much higher in stem than in other organs. Stem-ear interactions are key determinants of drought tolerance, in which expression of genes related to abscisic acid, lignin, and flavonoid biosynthesis and carbon metabolism in the stem was induced by drought, which inhibited stem elongation and promoted assimilate allocation to the ear in FM985. In comparison with ZD958, the activities of trehalose 6-phosphate phosphatase and sucrose non-fermentation-associated kinase 1 were higher in the stem and lower in the kernel of FM985, which facilitated kernel formation. These results reveal that, beyond the ear response, stem elongation is involved in the whole process of drought tolerance before silking. Abscisic acid together with trehalose 6-phosphate, lignin, and flavonoid suppresses stem elongation and allocates assimilates into the ear, providing a novel and systematic regulatory pathway for drought tolerance in maize.


Assuntos
Ácido Abscísico , Resistência à Seca , Ácido Abscísico/metabolismo , Zea mays/metabolismo , Lignina/metabolismo , Flavonoides/metabolismo , Trealose/metabolismo , Grão Comestível , Secas , Fosfatos/metabolismo , Estresse Fisiológico
2.
J Cell Physiol ; : e31387, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014890

RESUMO

Keratins are typical intermediate filament proteins of the epithelium that exhibit highly specific expression patterns related to the epithelial type and stage of cellular differentiation. They are important for cytoplasmic stability and epithelial integrity and are involved in various intracellular signaling pathways. Several keratins are associated with enamel formation. However, information on their expression patterns during tooth development remains lacking. In this study, we analyzed the spatiotemporal expression of keratin family members during tooth development using single-cell RNA-sequencing (scRNA-seq) and microarray analysis. scRNA-seq datasets from postnatal Day 1 mouse molars revealed that several keratins are highly expressed in the dental epithelium, indicating the involvement of keratin family members in cellular functions. Among various keratins, keratin 5 (Krt5), keratin 14 (Krt14), and keratin 17 (Krt17) are highly expressed in the tooth germ; KRT17 is specifically expressed in the stratum intermedium (SI) and stellate reticulum (SR). Depletion of Krt17 did not affect cell proliferation in the dental epithelial cell line SF2 but suppressed their differentiation ability. These results suggest that Krt17 is essential for SI cell differentiation. Furthermore, scRNA-seq results indicated that Krt5, Krt14, and Krt17 exhibited distinct expression patterns in ameloblast, SI, and SR cells. Our findings contribute to the elucidation of novel mechanisms underlying tooth development.

3.
Clin Genet ; 105(3): 243-253, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37937686

RESUMO

Amelogenesis imperfecta (AI) represents a group of clinically and genetically heterogeneous disorders that affect enamel formation and mineralization. Although AI is commonly considered a monogenic disorder, digenic inheritance is rarely reported. In this study, we recruited two nonconsanguineous Chinese families exhibiting diverse phenotypes of enamel defects among affected family members. Digenic variants were discovered in both probands. In family 1, the proband inherited a paternal frameshift variant in LAMA3 (NM_198129.4:c.3712dup) and a maternal deletion encompassing the entire AMELX gene. This resulted in a combined hypoplastic and hypomineralized AI phenotype, which was distinct from the parents' manifestations. In family 2, whole-exome sequencing analysis revealed the proband carried a maternal heterozygous splicing variant in COL17A1 (NC_000010.11 (NM_000494.3): c.4156 + 2dup) and compound heterozygous variants in RELT (paternal: NM_032871.4:c.260A > T; maternal: NM_032871.4:c.521 T > G). These genetic changes caused the abundant irregular enamel defects observed in the proband, whereas other affected family members carrying heterozygous variants in both COL17A1 and RELT displayed only horizontal grooves as their phenotype. The pathogenicity of the novel COL17A1 splice site variant was confirmed through RT-PCR and minigene assay. This study enhances our understanding by highlighting the potential association between the co-occurrence of variants in two genes and variable phenotypes observed in AI patients.


Assuntos
Amelogênese Imperfeita , Humanos , Amelogênese Imperfeita/genética , Fenótipo , Mutação da Fase de Leitura/genética , Proteínas da Matriz Extracelular/genética , Variação Biológica da População , Linhagem
4.
Analyst ; 149(12): 3363-3371, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38712505

RESUMO

Specific detection of glycoproteins such as transferrin (TRF) related to neurological diseases, hepatoma and other diseases always plays an important role in the field of disease diagnosis. We designed an antibody-free immunoassay sensing method based on molecularly imprinted polymers (MIPs) formed by the polymerization of multiple functional monomers for the sensitive and selective detection of TRF in human serum. In the sandwich surface-enhanced Raman spectroscopy (SERS) sensor, the TRF-oriented magnetic MIP nanoparticles (Fe3O4@SiO2-MIPs) served as capture units to specifically recognize TRF and 4-mercaptophenylboronic acid-functionalized gold nanorods (MPBA-Au NRs) served as SERS probes to label the targets. In order to achieve stronger interaction between the recognition cavities of the prepared MIPs and the different amino acid fragments that make up TRF, Fe3O4@SiO2-MIPs were obtained through polycondensation reactions between more silylating reagents, enhancing the specific recognition of the entire TRF protein and achieving high IF. This sensing method exhibited a good linear response to TRF within the TRF concentration range of 0.01 ng mL-1 to 1 mg mL-1 (R2 = 0.9974), and the LOD was 0.00407 ng mL-1 (S/N = 3). The good stability, reproducibility and specificity of the resulting MIP based SERS sensor were demonstrated. The determination of TRF in human serum confirmed the feasibility of the method in practical applications.


Assuntos
Polímeros Molecularmente Impressos , Análise Espectral Raman , Transferrina , Humanos , Ácidos Borônicos/química , Ouro/química , Limite de Detecção , Nanopartículas de Magnetita/química , Polímeros Molecularmente Impressos/química , Nanotubos/química , Dióxido de Silício/química , Análise Espectral Raman/métodos , Compostos de Sulfidrila , Transferrina/análise , Transferrina/química
5.
Environ Sci Technol ; 58(6): 2881-2890, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38297912

RESUMO

The use of microbial electrochemical sensors, with electroactive biofilms (EABs) as sensing elements, is a promising strategy to timely measure the biochemical oxygen demand (BOD) of wastewater. However, accumulation of Coulombic yield over a complete degradation cycle is time-consuming. Therefore, understanding the correlation between current output and EAB metabolism is urgently needed. Here, we recognized a tail stage (TS) on a current-time curve according to current increase rate─a period with the least electron harvesting efficiency. EAB adopted a series of metabolic compensation strategies, including slow metabolism of residual BOD, suspended growth, reduced cell activity, and consumption of carbon storage polymers, to cope with substrate deficiency in TS. The supplementary electrons provided by the decomposition of glycogen and fatty acid polymers increased the Coulombic efficiencies of TS to >100%. The tail current produced by spontaneous metabolic compensation showed a trend of convergent exponential decay, independent of BOD concentration. Therefore, we proposed the TS prediction model (TSPM) to predict Coulombic yield, which shortened BOD measurement time by 96% (to ∼0.5 h) with deviation <4 mg/L when using real domestic wastewater. Our findings on current output in TS give insights into bacterial substrate storage and consumption, as well as regulation in substrate-deficient environment, and provide a basis for developing BOD sensors.


Assuntos
Técnicas Biossensoriais , Águas Residuárias , Biofilmes , Bactérias/metabolismo , Oxigênio/análise , Polímeros
6.
Environ Sci Technol ; 58(37): 16386-16398, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39236260

RESUMO

Plastic additive-related chemicals, particularly in polyvinyl chloride (PVC) plastics, have become a key issue in plastic pollution. Although addressing plastic pollution through the life-cycle approach is crucial, the environmental impacts of typical plastic additive-related chemicals in PVC plastics during the cradle-to-gate stage remain unexplored. Consequently, managing the life-cycle environmental impacts of these additives remains challenging. Herein, the environmental impacts of 23 typical plastic additive-related chemicals and six PVC plastic products were evaluated throughout the cradle-to-gate life-cycle stage using a life cycle assessment-material flow analysis (LCA-MFA) coupled model. The results indicate that plastic additives significantly contribute to the environmental impacts of PVC plastic products across various end point indicators, ranging from 8.7 to 40.6%. Additionally, scenario analysis (SA) reveals that conventional strategies for addressing plastic pollution may not be highly effective in mitigating the environmental impacts associated with plastic additives. Specifically, compared to primary polymers, these additives exhibit 4 to 13% lower mitigation potential under the same policy scenarios. However, technical adjustment strategies targeting additives show a mitigation potential of 12 to 39%, suggesting that guiding the plastic additive industry toward green transformation is a key strategy for reducing environmental impacts.


Assuntos
Plásticos , Cloreto de Polivinila , Cloreto de Polivinila/química , Meio Ambiente , Poluição Ambiental
7.
J Nanobiotechnology ; 22(1): 547, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39238027

RESUMO

Rheumatoid arthritis (RA) involves chronic inflammation, oxidative stress, and complex immune cell interactions, leading to joint destruction. Traditional treatments are often limited by off-target effects and systemic toxicity. This study introduces a novel therapeutic approach using hyaluronic acid (HA)-conjugated, redox-responsive polyamino acid nanogels (HA-NG) to deliver tacrolimus (TAC) specifically to inflamed joints. The nanogels' disulfide bonds enable controlled TAC release in response to high intracellular glutathione (GSH) levels in activated macrophages, prevalent in RA-affected tissues. In vitro results demonstrated that HA-NG/TAC significantly reduced TAC toxicity to normal macrophages and showed high biocompatibility. In vivo, HA-NG/TAC accumulated more in inflamed joints compared to non-targeted NG/TAC, enhancing therapeutic efficacy and minimizing side effects. Therapeutic evaluation in collagen-induced arthritis (CIA) mice revealed HA-NG/TAC substantially reduced paw swelling, arthritis scores, synovial inflammation, and bone erosion while suppressing pro-inflammatory cytokine levels. These findings suggest that HA-NG/TAC represents a promising targeted drug delivery system for RA, offering potential for more effective and safer clinical applications.


Assuntos
Artrite Experimental , Artrite Reumatoide , Ácido Hialurônico , Nanogéis , Peptídeos , Tacrolimo , Animais , Ácido Hialurônico/química , Artrite Reumatoide/tratamento farmacológico , Camundongos , Tacrolimo/farmacologia , Tacrolimo/uso terapêutico , Tacrolimo/química , Tacrolimo/farmacocinética , Artrite Experimental/tratamento farmacológico , Peptídeos/química , Peptídeos/farmacologia , Nanogéis/química , Masculino , Células RAW 264.7 , Sistemas de Liberação de Medicamentos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos Endogâmicos DBA , Portadores de Fármacos/química , Humanos
8.
Ecotoxicol Environ Saf ; 270: 115907, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38176185

RESUMO

Fluoride has strong electronegativity and exposes diversely in nature. Water fluoridation is the most pervasive form of occurrence, representing a significant threat to human health. In this study, we investigate the morphometric and physiological alterations triggered by fluoride stimulation during the embryogenesis of zebrafish and reveal its putative effects of stage- and/or dose-dependent. Fluoride exhibits potent biological activity and can be extensively absorbed by the yolk sac, exerting significant effects on the development of multiple organs. This is primarily manifested as restricted nutrient utilization and elevated levels of lipid peroxidation, further leading to the accumulation of superoxide in the yolk sac, liver, and intestines. Moreover, pericardial edema exerts pressure on the brain and eye development, resulting in spinal curvature and reduced body length. Besides, acute fluoride exposure with varying concentrations has led to diverse teratogenic outcomes. A low dose of water fluoridation tends to induce abnormal development of the embryonic yolk sac, while vascular malformation is widely observed in all fluoride-treated groups. The effect of fluoride exposure on blood circulation is universally present, even in zebrafish larvae that do not exhibit obvious deformities. Their swimming behavior is also affected by water fluoridation, resulting in reduced activity and delayed reactions. In conclusion, this study provides valuable insights into the monitoring of environmental quality related to water fluoridation and disease prevention.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Humanos , Fluoretos/toxicidade , Fluoretação , Desenvolvimento Embrionário , Saco Vitelino , Embrião não Mamífero , Poluentes Químicos da Água/toxicidade
9.
Mikrochim Acta ; 191(9): 516, 2024 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107665

RESUMO

Cupric ions (Cu2+), pyrophosphate (PPi), and alkaline phosphatase (ALP) are involved in a variety of biochemical processes such as DNA replication, cellular metabolism and play an important role in human growth and development. It is of great significance to establish a method for the sensitive detection of Cu2+, PPi and ALP. In this work, polyethyleneimine-capped silver nanoclusters (PEI-AgNCs) were successfully synthesized by a one-pot method using hydrazine sulfate as reductant, exhibiting a unique strong fluorescence emission in the near-ultraviolet region at ∼339 nm. Since the fluorescence of PEI-AgNCs can be quenched by Cu2+ through inner filtering effect (IFE), then recovered by competitive binding of pyrophosphate and Cu2+, and later weakened again by catalytic hydrolysis of alkaline phosphatase, a sensitive and selective strategy based on the changes of fluorescence "ON" or "OFF" was established to detect Cu2+, PPi and ALP. The LODs of these three analytes were 36 nM, 0.2 µM, and 0.14 U L-1 at a S/N ratio of 3, respectively. A series of logic gate circuits for sensing cupric ions, pyrophosphate, and alkaline phosphatase were successfully constructed. The established methods have the potential for biosensing and environmental analysis and the specific UV-A fluorescence property of PEI-AgNCs may be helpful in photonic and optical areas.


Assuntos
Fosfatase Alcalina , Cobre , Difosfatos , Nanopartículas Metálicas , Polietilenoimina , Prata , Espectrometria de Fluorescência , Prata/química , Polietilenoimina/química , Cobre/química , Nanopartículas Metálicas/química , Fosfatase Alcalina/análise , Fosfatase Alcalina/metabolismo , Difosfatos/análise , Difosfatos/química , Espectrometria de Fluorescência/métodos , Limite de Detecção , Humanos , Fluorescência , Raios Ultravioleta
10.
J Prosthet Dent ; 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38342644

RESUMO

STATEMENT OF PROBLEM: Current methods for assessing the accuracy of intraoral scanners (IOSs) that reduce errors and provide comprehensive data compared with previous methods are lacking. PURPOSE: The purpose of this in vitro study was to present a coordinate-based data analysis method to compare the accuracy of 5 IOSs for scanning completely dentate and partially edentulous casts. MATERIAL AND METHODS: Reference scans of 2 complete arch casts (completely and partially dentate) were digitized using a high-precision laboratory scanner (Ceramill Map 600). Each cast was scanned 10 times each using 5 IOSs (3Shape TRIOS 3, Planmeca Emerald, iTero Element 5D, Medit i500, and Shining Aoralscan 3). The dataset of all 10 test groups was analyzed by using a reverse engineering software program (Geomagic Wrap). Each test cast was aligned with the reference cast by 3-dimensional (3D) superimposition to determine the translation and rotation along the x-, y-, and z-axes. The dataset was analyzed using the Kruskal-Wallis and post hoc Bonferroni tests (α=.05). RESULTS: Significant differences were observed in all parameters among all scanners when scanning the same cast (P<.05). Significant differences were observed in at least 1 parameter for all scanners, except Element 5D after scanning different casts using the same scanner. Deviations in the test data generally relocated toward the mesial, buccal, and apical sides, and the casts were almost always rotated clockwise around the y-axis and counterclockwise around the z-axis. For the completely dentate cast, among all IOSs, Element 5D demonstrated the highest accuracy in most of the measured parameters, specifically in the y-axis translation (0.06[0.07] mm), z-axis translation (0.08[0.05] mm), and y-axis rotation (0.21[0.16] degree) (P<.05). For the partially edentulous cast, Element 5D displayed higher accuracy in most of the measured parameters, including the x-axis translation (0.11[0.14] mm) and z-axis rotation (0.12[0.18] degree) (P<.05). Emerald also displayed higher accuracy in most of the measured parameters, including the y-axis translation (0.05[0.08] mm) and y-axis rotation (0.14[0.12] degree) (P<.05). Element 5D exhibited no difference in the scanning accuracy between the 2 types of casts (P>.05). CONCLUSIONS: Element 5D offered a high level of accuracy and was an appropriate scanner for both situations. The method presented in this study provides a good assessment of accuracy deviations in complete arch scans using 3D coordinate-based data analysis.

11.
Environ Geochem Health ; 46(10): 374, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167242

RESUMO

Globally, microplastic pollution of soil ecosystems poses a major risk. The early studies found that the impact of microplastics on different plants could vary depending on the type of microplastic, the mass concentration or the plant species. This study investigated the effect of 3 mass concentrations (0.1%, 1%, and 2.5%) and 3 types of microplastics (PE MPs, PLA MPs, and PVC MPs) on adzuki bean biomass, root traits, Chlorophyll content and antioxidant enzymes. According to our findings, all microplastics had an impact on biomass, but PLA MPs had the strongest inhibitory effect. The high mass concentration of microplastics had a significant influence on chlorophyll content. Adzuki beans exhibited varying degrees of damage upon exposure to microplastics, but they were able to withstand the oxidative stress brought on by PE MPs by increasing the activity of antioxidant enzymes (SOD and POD). Comparing the adverse effects of PE MPs on adzuki beans to those of PLA MPs and PVC MPs, principal component analysis and membership function value analysis revealed that the former had fewer impacts. Disparities in the observed effects may be attributed to variations in the properties of microplastics. Subsequent investigations into the mechanisms underlying microplastic toxicity need a more comprehensive exploration.


Assuntos
Clorofila , Microplásticos , Poluentes do Solo , Vigna , Vigna/efeitos dos fármacos , Microplásticos/toxicidade , Clorofila/metabolismo , Poluentes do Solo/toxicidade , Biomassa , Raízes de Plantas/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes
12.
BMC Oral Health ; 24(1): 904, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112986

RESUMO

BACKGROUND: Multi-rooted teeth with extensive dental defects often face challenges in stability and biomechanical failure. High-performance polymer PEEK materials, with properties closer to dentin, show promise in reducing stress concentration and preserving tooth structure. This report aimed to explore the use of a highly retentive polyetheretherketone (PEEK) for manufacturing custom-made split post and core for the restoration of grossly destroyed endodontically treated molars. CLINICAL CONSIDERATIONS: A 40-year-old female patient presented with complaints of loss of tooth substance in the posterior mandibular tooth. This case involved the digital design and fabrication of PEEK split post and core to restore multirooted molar with insufficient dental tissue remnants. The restorations were evaluated over a 3-year follow-up using the World Federation criteria (FDI). The restoration was clinically evaluated through intraoral examination, radiographic assessment, and subjective patient satisfaction, and was deemed clinically good according to FDI criteria. CONCLUSION: The outstanding mechanical properties of PEEK, coupled with the structure of the split post, provide an effective treatment option for weakened multirooted teeth. Simultaneously, the restoration configuration effectively addressed the challenge of varying postinsertion directions, and the interlocking mechanism between the primary and auxiliary posts enhanced the stability of the post and core.


Assuntos
Benzofenonas , Cetonas , Dente Molar , Polietilenoglicóis , Polímeros , Humanos , Feminino , Adulto , Dente Molar/cirurgia , Técnica para Retentor Intrarradicular , Seguimentos , Planejamento de Prótese Dentária , Dente não Vital/cirurgia , Desenho Assistido por Computador
13.
BMC Oral Health ; 24(1): 536, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715009

RESUMO

BACKGROUND: Oral traumatic ulcerative lesions (OTUL) are commonly encountered in clinical practice, yet there is limited research on their clinical characteristics and traumatic etiological factors. This retrospective study aimed to analyze the age, gender, clinical characteristics, and traumatic etiological factors in a large cohort of patients with OTUL and provide valuable insights for dental clinicians to optimize patient care and prevention strategies. METHODS: A total of 1543 patients with OTUL were enrolled in this study. Age, gender, medical history, clinical characteristics and traumatic etiological factors were collected and analyzed. Logistic regression analysis was performed to determine the significance of age and gender as factors related to OTUL. RESULTS: The study revealed significant variations in clinical characteristics and traumatic etiological factors among different age groups and between genders. Logistic regression analysis demonstrated that both age and gender were significant factors related to OTUL. CONCLUSION: The clinical characteristics of OTUL and traumatic etiological factors appear to be significantly different according to age and gender. More targeted prevention strategies should be implemented for all age and gender groups.


Assuntos
Úlceras Orais , Humanos , Masculino , Feminino , Estudos Retrospectivos , Adulto , Fatores Sexuais , Pessoa de Meia-Idade , Fatores Etários , Úlceras Orais/etiologia , Adolescente , Adulto Jovem , Idoso , Criança , Pré-Escolar , Fatores de Risco , Idoso de 80 Anos ou mais
14.
J Prosthodont ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38566576

RESUMO

The purpose of this technical report is to demonstrate a fully digital workflow for designing and fabricating metal frameworks and removable partial dentures. After obtaining a digital cast of the dental arch with bilateral distal extension defect, computer-aided design software and 3D printing technology are used for the design and fabrication of the removable partial denture frameworks, denture teeth, and denture bases, instead of the traditional workflow. The assembly of the three components is facilitated through a meticulously structured framework. The technology, which prints metal frameworks, denture bases, and denture teeth through different processes with different materials, achieves full 3D printing technology for making removable partial dentures.

15.
Clin Genet ; 104(2): 259-265, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37092250

RESUMO

Biallelic pathogenic variants in RNASEH2C cause Aicardi-Goutières syndrome 3 (AGS3, MIM #610329), a rare early-onset encephalopathy characterized by intermittent unexplained fever, chilblains, irritability, progressive microcephaly, dystonia, spasticity, severe psychomotor retardation and abnormal brain imaging. Currently, approximately 50 individuals with AGS3 and 19 variants in RNASEH2C have been revealed. Here, we reported the novel clinical manifestations and genotypic information of three unrelated Chinese patients with AGS3 caused by pathogenic variants in RNASEH2C. In addition to three novel missense variants (c.101G>A, p.Cys34Tyr; c.401T>A, p.Leu134Gln and c.434G>T, p.Arg145Leu), one missense variant (c.194G>A, p.Gly65Asp) reoccurred in all patients but was completely absent in South Asian and other ethnicities. Our study expanded the variant spectrum of RNASEH2C and identified RNASEH2C c.194G>A as a Chinese-specific founder mutation. The novel phenotypes, including mouth ulcers, hip dysplasia, retarded dentition and hypogonadism, observed in our patients greatly enriched the clinical characteristics of AGS3.


Assuntos
Doenças Autoimunes do Sistema Nervoso , Encefalopatias , Malformações do Sistema Nervoso , Humanos , Doenças Autoimunes do Sistema Nervoso/etnologia , Doenças Autoimunes do Sistema Nervoso/genética , Encéfalo/patologia , Encefalopatias/etnologia , Encefalopatias/genética , População do Leste Asiático/genética , Mutação , Malformações do Sistema Nervoso/etnologia , Malformações do Sistema Nervoso/genética
16.
Plant Cell ; 32(12): 3825-3845, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33037146

RESUMO

Catechyl lignin (C-lignin) is a linear homopolymer of caffeyl alcohol found in the seed coats of diverse plant species. Its properties make it a natural source of carbon fibers and high-value chemicals, but the mechanism of in planta polymerization of caffeyl alcohol remains unclear. In the ornamental plant Cleome hassleriana, lignin biosynthesis in the seed coat switches from guaiacyl lignin to C-lignin at ∼12 d after pollination. Here we found that the transcript profile of the laccase gene ChLAC8 parallels the accumulation of C-lignin during seed coat development. Recombinant ChLAC8 oxidizes caffeyl and sinapyl alcohols, generating their corresponding dimers or trimers in vitro, but cannot oxidize coniferyl alcohol. We propose a basis for this substrate preference based on molecular modeling/docking experiments. Suppression of ChLAC8 expression led to significantly reduced C-lignin content in the seed coats of transgenic Cleome plants. Feeding of 13C-caffeyl alcohol to the Arabidopsis (Arabidopsis thaliana) caffeic acid o-methyltransferase mutant resulted in no incorporation of 13C into C-lignin, but expressing ChLAC8 in this genetic background led to appearance of C-lignin with >40% label incorporation. These results indicate that ChLAC8 is required for C-lignin polymerization and determines lignin composition when caffeyl alcohol is available.


Assuntos
Arabidopsis/enzimologia , Cleome/enzimologia , Lacase/metabolismo , Lignina/metabolismo , Arabidopsis/genética , Cleome/genética , Regulação da Expressão Gênica de Plantas , Lacase/genética , Metiltransferases/genética , Metiltransferases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Polimerização , Metabolismo Secundário , Sementes/enzimologia , Sementes/genética , Especificidade por Substrato
17.
Macromol Rapid Commun ; 44(18): e2300198, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37231589

RESUMO

Modulating on-demand polymerization is a challenge in synthetic macromolecules. Herein, tailoring polymerization controllability and dispersity during single-electron transfer mediated living radical polymerization (SET-LRP) of methyl methacrylate (MMA) is achieved. Hexaarylbiimidazole (HABI) is employed as a photoswitchable catalyst, allowing reversible control of catalytic activity between an active and inactive state. In the presence of HABI and with the light on (active state), control SET-LRP of MMA follows first-order kinetics, resulting in polymers with a narrow molecular weight distribution. In contrast, polymerization responds to light and reverts to their original uncontrolled state with light off (inactive state). Therefore, repeatable resetting polymerization can be easily performed. The key to photomodulating dispersity is to use an efficient molecular switch to tailor the breadths of dispersity. Besides, the mechanism of HABI-mediated SET-LRP with switchable ability is proposed.


Assuntos
Polímeros , Polimerização , Substâncias Macromoleculares , Metilmetacrilato
18.
Oral Dis ; 29(8): 3654-3664, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35836351

RESUMO

OBJECTIVES: To investigate the detailed ultrastructural patterns of dental abnormalities affected by Axenfeld-Rieger syndrome (ARS) with a heterozygous microdeletion involving paired-like homeodomain 2 (PITX2) and explored the underlying molecular mechanisms driving enamel defects. SUBJECTS AND METHODS: Sanger sequencing, genomic quantitative PCR analysis, and chromosomal microarray analysis (CMA) were used to screen the disease-causing mutation in one ARS proband. An exfoliated tooth from an ARS patient was analyzed with scanning electron microscopy and micro-computerized tomography. A stable Pitx2 knockdown cell line was generated to simulate PITX2 haploinsufficiency. Cell proliferation and ameloblast differentiation were analyzed, and the role of the Wnt/ß-catenin pathway in proliferation of ameloblast precursor cells was investigated. RESULTS: An approximately 0.216 Mb novel deletion encompassing PITX2 was identified. The affected tooth displayed a thinner and broken layer of enamel and abnormal enamel biomineralization. PITX2 downregulation inhibited the proliferation and differentiation of inner enamel epithelial cells, and LiCl stifmulation partially reversed the proliferation ability after Pitx2 knockdown. CONCLUSIONS: Enamel formation is disturbed in some patients with ARS. Pitx2 knockdown can influence the proliferation and ameloblast differentiation of inner enamel epithelial cells, and PITX2 may regulate cell proliferation via Wnt/ß-catenin signaling pathway.


Assuntos
Doenças Dentárias , Fatores de Transcrição , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Segmento Anterior do Olho , Esmalte Dentário
19.
Plant Dis ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38037206

RESUMO

In July 2022, dieback and discoloration were detected on infected stems of peanut in Qijiang District of Chongqing (106.56°E,29.41°N), China, with an incidence up to 5%. These peanut stems had disease symptoms typical of anthracnose with irregular gray-brown spots with dark brown edges, sunken, and necrotic. High temperature and high humidity were favorable for the growth of the pathogen. To isolate the pathogen, we collected 10 typical infected peanuts and cut one piece from each of symptomatic stems, surface sterilized with 0.5% NaClO for 1 min, and 75% ethanol for 30 s, then rinsed three times with sterile distilled water and dried on sterilized filter paper. These pieces were incubated on potato dextrose agar (PDA) at 25°C in the dark. Pure cultures were obtained from hyphal tips of each colony. It was found that isolates with the same colony morphology were isolated from each infected stem. A representative isolate (L7) was used for morphological characterization, molecular analysis, phylogenetic analysis, and pathogenicity tests. The colonies appeared white to gray, with white margins and aerial hyphae, and the reverse of the colonies was gray to brown. Conidia were cylindrical, aseptate, with obtuse to slightly rounded ends, 13.4 to 18.8 × 4.2 to 5.8 µm (n=50). Morphological characteristics were generally consistent with those of Colletotrichum gloeosporioides species complex (Cannon et al., 2012). For molecular identification, genomic DNA was extracted using a CTAB method and partial sequences of ß-tubulin (TUB2), actin (ACT) genes, chitin synthase (CHS) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were amplified and sequenced using primers T1/T2, ACT-512F/ACT-783R, CHS-79F/CHS-345R, and GDF1/GDR1, respectively (Damm et al., 2012; Dowling et al., 2020). Using the BLAST, TUB2, ACT, CHS and GAPDH gene sequences (GenBank accession No. OR714793, OP168707, OP168708 and OR714794, respectively) were100% (429 bp out of 429 bp), 99.22% (256 bp out of 258 bp), 99.64% (276 bp out of 277 bp) and 100% (253 bp out of 253 bp) identical to C. gloeosporioides CBS:112999 (JQ005587, JQ005500, JQ005326, and JQ005239), respectively. Using Neighbor-Joining algorithm, phylogenetic analysis was conducted based on the concatenated sequences of published TUB2, ACT, CHS and GAPDH genes. The identified isolate (L7) was closely related to C. gloeosporioides. To evaluate pathogenicity, the stems of ten peanut (Zhonghua12) seedlings (2 weeks) were wounded with a sterile toothpick and mycelial plugs (5 mm in diameter) or 20 µl of conidial suspension (105/ml) were inoculated. Non-colonized agar plugs or 20 µl of sterile distilled water were treated as control. After inoculation, the peanuts were kept in a moist chamber at 28°C with 80% humidity in the dark for 24 h, and subsequently transferred to the moist chamber with 12 h light and darkness cycle for 6 days, similar symptoms were observed on all inoculated peanuts. Controls remained asymptomatic. C. gloeosporioides was reisolated from the diseased stems and confirmed using morphological features and sequence analysis of TUB2, ACT, CHS and GAPDH. Anthracnose caused by C. truncatum and C. fructicola has been reported on peanut leaves in China (Gong et al., 2023; Yu et al., 2019). To our knowledge, this is the first report of anthracnose on peanut stem caused by C. gloeosporioides in Chongqing. Our report will provide crucial information for studying on epidemiology and management of this disease.

20.
J Craniofac Surg ; 34(6): 1784-1788, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36991544

RESUMO

The nasolabial folds (NLFs) may be shallowed with the use of nostril base augmentation. This study aimed to design and customize patient-specific implants (PSIs) with computer-aided design/computer-aided manufacturing (CAD/CAM) to correct NLF deepening caused by midfacial aging. The patient's head computed tomography data obtained and were used for reconstruction. The PSIs were customized by CAD/CAM techniques, which were implanted into a nasal base for shallow NLFs caused by midfacial aging. Preoperative and postoperative photos and a wrinkle severity rating scale were used to evaluate the changes in NLFs. Also, the global esthetic improvement scale was used to investigate the surgical satisfaction of patients. Eleven patients (22 NLFs) received PSIs in the nasal base (22 implants). The customized PSI matched well with premaxilla, reducing the difficulty of operation. After 3 to 12 months of follow-up, PSI was stable without foreign body reaction or inflammatory reaction. Postoperative wrinkle severity rating scale scores showed that NLF severity was reduced in all patients, with a significant esthetic improvement compared with preoperatively ( P < 0.01). The global esthetic improvement scale showed an extremely satisfied improved NLF in 27.27% of patients, much improved in 63.63%, and improved in 9.90% (2/22), and none reported change or poor NLF. Patient satisfaction with their midface appearance differed significantly before and after surgery ( P < 0.01). Individualized PSI designed with high precision and matching degree by CAD and prepared using CAM could be applied to overcome the limitations of noncustomized implants.


Assuntos
Implantes Dentários , Envelhecimento da Pele , Humanos , Sulco Nasogeniano , Satisfação do Paciente , Envelhecimento , Ácido Hialurônico
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