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1.
Int J Syst Evol Microbiol ; 70(2): 1178-1185, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31860431

RESUMO

During a survey of endophytic fungi in plant roots in secondary forests in Yunnan, China, a novel ascomyceteous taxon, Beltrania sinensis, was isolated from Quercus cocciferoides Hand.-Mazz. and Fraxinus malacophylla Hemsl. This novel species is characterized by having oval or obovoid conidiogenous cells with several apical, flat-tipped denticles, and biconic, aseptate, smooth, pale brown conidia with a hyaline to subhyaline equatorial transverse band and apical tubular appendage. Phylogenetic analysis of the combined sequences of the internal transcribed spacer and the LSU rRNA gene confirmed its novel species status within the genus Beltrania. Here, the novel species is described and illustrated, and a taxonomic key to species in the genus Beltrania is provided.


Assuntos
Filogenia , Raízes de Plantas/microbiologia , Quercus/microbiologia , Xylariales/classificação , China , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , Análise de Sequência de DNA , Esporos Fúngicos , Xylariales/isolamento & purificação
2.
New Phytol ; 221(4): 1703-1723, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30312479

RESUMO

Contents Summary 1703 I. Introduction 1703 II. Cellulose biosynthesis 1705 III. Xylan biosynthesis 1709 IV. Glucomannan biosynthesis 1713 V. Lignin biosynthesis 1714 VI. Concluding remarks 1717 Acknowledgements 1717 References 1717 SUMMARY: Secondary walls are synthesized in specialized cells, such as tracheary elements and fibers, and their remarkable strength and rigidity provide strong mechanical support to the cells and the plant body. The main components of secondary walls are cellulose, xylan, glucomannan and lignin. Biochemical, molecular and genetic studies have led to the discovery of most of the genes involved in the biosynthesis of secondary wall components. Cellulose is synthesized by cellulose synthase complexes in the plasma membrane and the recent success of in vitro synthesis of cellulose microfibrils by a single recombinant cellulose synthase isoform reconstituted into proteoliposomes opens new doors to further investigate the structure and functions of cellulose synthase complexes. Most genes involved in the glycosyl backbone synthesis, glycosyl substitutions and acetylation of xylan and glucomannan have been genetically characterized and the biochemical properties of some of their encoded enzymes have been investigated. The genes and their encoded enzymes participating in monolignol biosynthesis and modification have been extensively studied both genetically and biochemically. A full understanding of how secondary wall components are synthesized will ultimately enable us to produce plants with custom-designed secondary wall composition tailored to diverse applications.


Assuntos
Parede Celular/metabolismo , Celulose/metabolismo , Lignina/metabolismo , Células Vegetais/metabolismo , Celulose/química , Glucosiltransferases/metabolismo , Lignina/química , Proteínas de Plantas/metabolismo , Domínios Proteicos , Xilanos/química , Xilanos/metabolismo
3.
Macromol Rapid Commun ; 40(17): e1800733, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30817055

RESUMO

The covalent cross-linked rubber has outstanding mechanical properties and chemical resistance, making it possible for a wide range of applications. Towards efforts to resource waste and environmental pollution, rubber recycling is a concerning problem. However, it is a big challenge to endow the most widely used commercial rubber systems with recyclability. In this paper, a novel reprocessable and recyclable acrylonitrile-butadiene rubber (NBR) is developed by introducing oxime-carbamate bonds into the raw NBR. Amidoxime NBR is prepared by a nucleophilic addition reaction of hydroxylamine hydrochloride and raw NBR, and then cross-linked amidoxime NBR using different amounts of toluene diisocynate (TDI). Results show that the obtained material exhibits good reprocessable property; the repairing efficiency exceeds 90% after two remoldings. In addition, it also has better mechanical properties: A tensile strength reaching a maximum value of 4.85 MPa when TDI cross-linker is 15.36 wt%, which is superior to vulcanized NBR (3.18 MPa).


Assuntos
Acrilonitrila/química , Butadienos/química , Carbamatos/química , Oximas/química , Polímeros/química , Reciclagem/métodos , Borracha/química , Resistência à Tração
4.
Plant Cell Physiol ; 56(2): 195-214, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25294860

RESUMO

Secondary walls are mainly composed of cellulose, hemicelluloses (xylan and glucomannan) and lignin, and are deposited in some specialized cells, such as tracheary elements, fibers and other sclerenchymatous cells. Secondary walls provide strength to these cells, which lend mechanical support and protection to the plant body and, in the case of tracheary elements, enable them to function as conduits for transporting water. Formation of secondary walls is a complex process that requires the co-ordinated expression of secondary wall biosynthetic genes, biosynthesis and targeted secretion of secondary wall components, and patterned deposition and assembly of secondary walls. Here, we provide a comprehensive review of genes involved in secondary wall biosynthesis and deposition. Most of the genes involved in the biosynthesis of secondary wall components, including cellulose, xylan, glucomannan and lignin, have been identified and their co-ordinated activation has been shown to be mediated by a transcriptional network encompassing the secondary wall NAC and MYB master switches and their downstream transcription factors. It has been demonstrated that cortical microtubules and microtubule-associated proteins play important roles in the targeted secretion of cellulose synthase complexes, the oriented deposition of cellulose microfibrils and the patterned deposition of secondary walls. Further investigation of many secondary wall-associated genes with unknown functions will provide new insights into the mechanisms controlling the formation of secondary walls that constitute the bulk of plant biomass.


Assuntos
Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Plantas/genética , Plantas/metabolismo , Transcrição Gênica , Biopolímeros/biossíntese
5.
Talanta ; 271: 125646, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218058

RESUMO

Uric acid (UA) monitoring is the most effective method for diagnosis and treatment of gout, hyperuricemia, hypertension, and other diseases. However, challenges remain regarding detection efficiency and rapid on-site detection. Here, we first synthesized a CdS/Au/TiO2-NTAs Z-scheme heterojunction material using a titanium dioxide nanotube array (TiO2-NTAs) as the substrate and modified with gold nanoparticles (Au) and cadmium sulfide particles (CdS). This material achieves bandgap alignment to generate a large number of electron-hole pairs under illumination. Then, using CdS/Au/TiO2-NTAs as the working electrode and molecularly imprinted polymers (MIP) as the recognition unit, we constructed a portable photoelectrochemical (PEC) sensor for non-invasive instant detection of UA concentration in human saliva, which has unique advantages in the field of high-sensitivity PEC instant detection. The portable MIP-PEC sensor achieves a linear range of 0.01-50 µM and a detection limit as low as 5.07 nM (S/N = 3). At the same time, the portable MIP-PEC sensor exhibits excellent sensitivity, specificity as well as stability, and shows no statistically significant difference compared to traditional high-performance liquid chromatography (HPLC) in practical sample detection. Compared to traditional PEC modes, this work demonstrates a novel and universal method for high-sensitivity instant detection in the field of PEC.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanotubos , Humanos , Ácido Úrico , Ouro/química , Saliva , Nanotubos/química , Técnicas Eletroquímicas/métodos , Limite de Detecção
6.
Colloids Surf B Biointerfaces ; 234: 113691, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38070369

RESUMO

SEMA4D-modified titanium surfaces can indirectly regulate macrophages through endothelial cells to achieve an anti-inflammatory effect, which is beneficial for healing soft tissues around the gingival abutment. However, the mechanism of surface-induced cellular phenotypic changes in SEMA4D-modified titanium has not yet been elucidated. SEMA4D activates the RhoA signaling pathway in endothelial cells, which coordinates metabolism and cytoskeletal remodeling. This study hypothesized that endothelial cells inoculated on SEMA4D-modified titanium surfaces can direct M2 polarization of macrophages via metabolites. An indirect co-culture model of endothelial cells and macrophages was constructed in vitro, and specific inhibitors were employed. Subsequently, endothelial cell adhesion and migration, metabolic changes, Rho/ROCK1 expression, and inflammatory expression of macrophages were assessed via immunofluorescence microscopy, specific kits, qRT-PCR, and Western blotting. Moreover, an in vivo rat bilateral maxillary implant model was constructed to evaluate the soft tissue healing effect. The in vitro experiments showed that the SEMA4D group had stronger endothelial cell adhesion and migration, increased Rho/ROCK1 expression, and enhanced release of lactate. Additionally, decreased macrophage inflammatory expression was observed. In contrast, the inhibitor group partially suppressed lactate metabolism and motility, whereas increased inflammatory expression. The in vivo analyses indicated that the SEMA4D group had faster and better angiogenic and anti-inflammatory effects, especially in the early stage. In conclusion, via the Rho/ROCK1 signaling pathway, the SEMA4D-modified titanium surface promotes endothelial cell adhesion and migration and lactic acid release, then the paracrine lactic acid promotes the polarization of macrophages to M2, thus obtaining the dual effects of angiogenesis and anti-inflammation.


Assuntos
Antígenos CD , Células Endoteliais , Semaforinas , Titânio , Ratos , Animais , Titânio/farmacologia , Ácido Láctico , Macrófagos , Anti-Inflamatórios
7.
Histol Histopathol ; 38(4): 453-465, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36255176

RESUMO

Parafibromin is a protein encoded by the oncosuppressor CDC73 gene, whose mutation results in hyperparathyroidism-jaw tumor syndrome (HPT-JT) and parathyroid carcinoma. Down-regulation of parafibromin is linked to lung, gastric, colorectal, and ovarian cancer tumorigenesis. Parafibromin expression was detected by RT-PCR, bioinformatics analysis, Western blot, and immunohistochemistry; and compared with clinicopathological characteristics of breast cancer. CDC73-related genes and pathways were analyzed using bioinformatics analysis. Parafibromin expression was increased in breast cancer compared to normal tissues at both mRNA and protein levels (p<0.05). Among triple-negative breast cancers, it was higher in basal-like 1 than basal-like 2 patients (p<0.05) and mesenchymal than immunomodulatory patients (p<0.05). CDC73 mRNA expression was positively correlated with white race, non-infiltrating immune cells, favorable luminal subtypes of PAM50, and prognosis of breast cancer patients (p<0.05). The differential genes of CDC73 were classified into enzyme inhibitors, peptidase, and keratinization by KEGG (p<0.05). Similarly, it was classified into ribosomes, TGF-ß, oxidation phosphorylation, inositol phosphate metabolism, arachidonic acid metabolism, linoleic acid metabolism, ERBB, and VEGF signaling pathways by GSEA (p<0.05). The positively-correlated genes of CDC73 were involved in cell mobility, response to interferon α, nuclear pore and basket, and histone methyltransferase. The negatively-correlated genes of CDC73 were involved in the mitochondrial respiratory chain, thermogenesis, and ribosomes. Parafibromin expression was higher in invasive ductal than lobular carcinoma (p<0.05) and mucinous adenocarcinoma than others (p<0.05). Parafibromin immunoreactivity as an independent factor was positively associated with an increased overall survival rate of breast cancer patients (p<0.05). These findings suggest that up-regulation of parafibromin in breast cancer patients is closely linked to a favorable prognosis. It is involved in tumorigenesis and subsequent progression by regulating metabolism, ribosomes, and cytokines.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Prognóstico , Neoplasias da Mama/genética , Mutação , Fatores de Transcrição/genética , Carcinogênese , RNA Mensageiro , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
8.
Biomater Adv ; 147: 213344, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36841112

RESUMO

Here, we combined reversible addition-fragmentation chain transfer (RAFT) polymerization and amide coupling reaction to develop a novel drug-polymer conjugate using poly(AMA-co-IMMA)-b-poly(OEGMA) (termed as PAIPO) as nanocarriers. In order to enhance cellular uptake and obtain subsequent endo/lysosomal escape capacity, the dual-drugs-conjugated prodrug was then coupled with 2,3-dimethylmaleimide (DA) moieties and implanted with imidazolyl groups, respectively. Paclitaxel (PTX) was conjugated to PAIPO via 3,3'-dithiodipropionic acid (DPA) to construct a GSH-responsive moiety, while doxorubicin (DOX) was conjugated to PAIPO via 4-formyl benzoic acid to construct a pH-responsive moiety, which synergistically enabled a synchronized and precise drug delivery. The micelles self-assembled from DOX/PTX@PAIPODA showed an ideal average diameter (163.2-178.3 nm), contributing to passive targeting by the EPR effect. Moreover, a switch of the surface Zeta potential of micelles from steady negatively charged (- 9.74 ± 0.54 mV) at pH 7.4 to positively charged (+ 6.33 ± 1.25 mV) at pH 6.5, facilitated the long blood circulation and cellular endocytosis of micelles, respectively. More importantly, in vitro studies confirmed that DAM(DOXn/PTX) exhibited a strong synergism against tumor cells, and under slightly acidic conditions (pH 6.5), the combination index (CI) values for DAM(DOX1/PTX) on HeLa and Skov-3 cells were estimated to be 0.47 and 0.49 (previous to be 0.50 and 0.56 at pH 7.4), respectively. And in vivo results showed effective tumor accumulation potential, remarkable biosafety, and biocompatibility. Combined, such synchronized delivery approach based on multi-responsive micelles might potentiate the efficacy of combination chemotherapy in clinical cancer treatment.


Assuntos
Sistemas de Liberação de Medicamentos , Micelas , Humanos , Doxorrubicina/uso terapêutico , Paclitaxel/uso terapêutico , Polímeros , Quimioterapia Combinada
9.
Sci Rep ; 13(1): 4, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36593229

RESUMO

A potentially novel actinobacterium isolated from forest soil, Streptomyces sp. KSF103 was evaluated for its insecticidal effect against several mosquito species namely Aedes aegypti, Aedes albopictus, Anopheles cracens and Culex quinquefasciatus. Mosquito larvae and adults were exposed to various concentrations of the ethyl acetate (EA) extract for 24 h. Considerable mortality was evident after the EA extract treatment for all four important vector mosquitoes. Larvicidal activity of the EA extract resulted in LC50 at 0.045 mg/mL and LC90 at 0.080 mg/mL for Ae. aegypti; LC50 at 0.060 mg/mL and LC90 at 0.247 mg/mL for Ae. albopictus; LC50 at 2.141 mg/mL and LC90 at 6.345 mg/mL for An. cracens; and LC50 at 0.272 mg/mL and LC90 at 0.980 mg/mL for Cx. quinquefasciatus. In adulticidal tests, the EA extract was the most toxic to Ae. albopictus adults (LD50 = 2.445 mg/mL; LD90 = 20.004 mg/mL), followed by An. cracens (LD50 = 5.121 mg/mL; LD90 = 147.854 mg/mL) and then Ae. aegypti (LD50 = 28.873 mg/mL; LD90 = 274.823 mg/mL). Additionally, the EA extract exhibited ovicidal activity against Ae. aegypti (LC50 = 0.715 mg/mL; LC90 = 6.956 mg/mL), Ae. albopictus (LC50 = 0.715 mg/mL; LC90 = 6.956 mg/mL), and An. cracens (LC50 = 0.715 mg/mL; LC90 = 6.956 mg/mL), evaluated up to 168 h post-treatment. It displayed no toxicity on the freshwater microalga Chlorella sp. Beijerinck UMACC 313, marine microalga Chlorella sp. Beijerinck UMACC 258 and the ant Odontoponera denticulata. In conclusion, the EA extract showed promising larvicidal, adulticidal and ovicidal activity against Ae. aegypti, Ae. albopictus, An. cracens, and Cx. quinquefasciatus (larvae only). The results suggest that the EA extract of Streptomyces sp. KSF103 has the potential to be used as an environmental-friendly approach in mosquito control. The current study would serve as an initial step toward complementing microbe-based bioinsecticides for synthetic insecticides against medically important mosquitoes.


Assuntos
Aedes , Chlorella , Culex , Inseticidas , Streptomyces , Animais , Inseticidas/farmacologia , Extratos Vegetais/farmacologia , Mosquitos Vetores , Larva , Folhas de Planta
10.
Plant Cell Physiol ; 53(7): 1204-16, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22537759

RESUMO

Xylan, the second most abundant cell wall polysaccharide, is composed of a linear backbone of ß-(1,4)-linked xylosyl residues that are often substituted with sugar side chains, such as glucuronic acid (GlcA) and methylglucuronic acid (MeGlcA). It has recently been shown that mutations of two Arabidopsis family GT8 genes, GUX1 and GUX2, affect the addition of GlcA and MeGlcA to xylan, but it is not known whether they encode glucuronyltransferases (GlcATs) or indirectly regulate the GlcAT activity. In this study, we performed biochemical and genetic analyses of three Arabidopsis GUX genes to determine their roles in the GlcA substitution of xylan and secondary wall deposition. The GUX1/2/3 genes were found to be expressed in interfascicular fibers and xylem cells, the two major types of secondary wall-containing cells that have abundant xylan. When expressed in tobacco BY2 cells, the GUX1/2/3 proteins exhibited an activity capable of transferring GlcA residues from the UDP-GlcA donor onto xylooligomer acceptors, demonstrating that these GUX proteins possess xylan GlcAT activity. Analyses of the single, double and triple gux mutants revealed that simultaneous mutations of all three GUX genes led to a complete loss of GlcA and MeGlcA side chains on xylan, indicating that all three GUX proteins are involved in the GlcA substitution of xylan. Furthermore, a complete loss of GlcA and MeGlcA side chains in the gux1/2/3 triple mutant resulted in reduced secondary wall thickening, collapsed vessel morphology and reduced plant growth. Together, our results provide biochemical and genetic evidence that GUX1/2/3 are GlcATs responsible for the GlcA substitution of xylan, which is essential for normal secondary wall deposition and plant development.


Assuntos
Proteínas de Arabidopsis/química , Arabidopsis/enzimologia , Ácido Glucurônico/química , Glicosiltransferases/química , Xilanos/química , Arabidopsis/química , Proteínas de Arabidopsis/genética , Linhagem Celular , Parede Celular/química , Parede Celular/enzimologia , Celulose/química , Ativação Enzimática , Ensaios Enzimáticos , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Genes Reporter , Glicosiltransferases/genética , Mutação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Nicotiana/química , Nicotiana/genética , Xilema/química , Xilema/enzimologia , Xilema/genética
11.
Front Cell Dev Biol ; 10: 1006400, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211470

RESUMO

In this review, we discuss parafibromin protein, which is encoded by CDC73. A mutation in this gene causes hyperparathyroidism-jaw tumor (HPT-JT) syndrome, an autosomal dominant disease. CDC73 is transcriptionally downregulated by the Wilms' tumor suppressor gene WT1 and translationally targeted by miR-182-3p and miR-155. In the nucleus, parafibromin binds to RNA polymerase II and PAF1 complex for transcription. Parafibromin transcriptionally increases the expression of c-Myc, decreases CPEB1 expression by interacting with H3M4, and reduces cyclin D1 expression by binding to H3K9. The RNF20/RNF40/parafibromin complex induces monoubiquitination of H2B-K120, and SHP2-mediated dephosphorylation of parafibromin promotes the parafibromin/ß-catenin interaction and induces the expression of Wnt target genes, which is blocked by PTK6-medidated phosphorylation. Parafibromin physically associates with the CPSF and CstF complexes that are essential for INTS6 mRNA maturation. In the cytosol, parafibromin binds to hSki8 and eEF1Bγ for the destabilization of p53 mRNA, to JAK1/2-STAT1 for STAT1 phosphorylation, and to actinin-2/3 to bundle/cross-link actin filaments. Mice with CDC73 knockout in the parathyroid develop parathyroid and uterine tumors and are used as a model for HPT-JT syndrome. Conditional deletion of CDC73 in mesenchymal progenitors results in embryos with agenesis of the heart and liver while its abrogation in mature osteoblasts and osteocytes increases cortical and trabecular bone. Heterozygous germline mutations in CDC73 are associated with parathyroid carcinogenesis. The rates of CDC73 mutation and parafibromin loss decrease from parathyroid adenoma to atypical adenoma to carcinoma. In addition, down-regulated parafibromin is closely linked to the tumorigenesis, subsequent progression, or poor prognosis of head and neck, gastric, lung, colorectal, and ovarian cancers, and its overexpression might reverse the aggressiveness of these cancer cells. Therefore, parafibromin might be useful as a biological marker of malignancies and a target for their gene therapy.

12.
Orthop Surg ; 14(2): 443-450, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34914198

RESUMO

This study sought to investigate and evaluate a modified axial translaminar screw fixation for treating odontoid fractures. We performed a retrospective study at Wenzhou Medical University Affiliated Second Hospital between March 2016 and June 2018. We retrospectively collected and analyzed the medical records of 23 cases with odontoid fractures. All patients were identified as type II odontoid fractures without neurological deficiency and serious diseases following the classification of Anderson. The average age, gender ratio, and body mass index (BMI) were 54.3 ± 11.1 years, 12 men to 11 women, and 22.6 ± 2.4 kg/m2 , respectively. Patients in this study accepted screw fixation using our modified axial translaminar screw fixation combined with atlas pedicle or lateral mass screw fixation. Within the technique, a small cortical "window" was dug in the middle of the axial contralateral lamina, such that the screws in the lamina were visualized to prevent incorrectly implanting the posterior spinal canal through the visualized "window." A total of 46 bone screws were accurately inserted into the axial lamina without using fluoroscopy. The length of all translaminar screws ranged between 26 and 30 mm, while the diameter was 3.5 mm. During the follow-up survey, the visual analog scale (VAS) and neck disability index (NDI) were measured. We provide a simple modification of Wright's elegant technique with the addition of "visualized windows" at the middle of the axial lamina. In all patients, screws were inserted accurately without bony breach and the screw angle was 56.1 ± 3.0°. Mean operative time was 102 ± 28 min with an average blood loss of 50 ± 25 mL. Postoperative hemoglobin and mean length of hospital stay were 12.0 ± 1.4 g/dL and 10.4 ± 3.4 days, respectively. The average follow-up time of all cases was 14.7 months and no internal fixation displacement, loosening, or breakage was found. All patients with odontoid fractures reported being satisfied with the treatment during the recheck period and good clinical outcomes were observed. At 1, 6, and 12 months, NDI and VAS showed that the symptoms of neck pain and limitations of functional disability improved significantly during follow-up. Our results suggest that the modified translaminar screw fixation technique can efficiently treat Anderson type II odontoid fracture, followed by the benefits of less soft tissue dissection, simple operation, no fluoroscopy, and accurate placement of screws.


Assuntos
Processo Odontoide , Fraturas da Coluna Vertebral , Fusão Vertebral , Adulto , Idoso , Parafusos Ósseos , Feminino , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Processo Odontoide/diagnóstico por imagem , Processo Odontoide/lesões , Processo Odontoide/cirurgia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Fusão Vertebral/métodos , Resultado do Tratamento
13.
Plant Physiol ; 152(2): 1044-55, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19965968

RESUMO

Wood is the most abundant biomass produced by land plants. Dissection of the molecular mechanisms underlying the transcriptional regulation of wood formation is a fundamental issue in plant biology and has important implications in tree biotechnology. Although a number of transcription factors in tree species have been shown to be associated with wood formation and some of them are implicated in lignin biosynthesis, none of them have been demonstrated to be key regulators of the biosynthesis of all three major components of wood. In this report, we have identified a group of NAC domain transcription factors, PtrWNDs, that are preferentially expressed in developing wood of poplar (Populus trichocarpa). Expression of PtrWNDs in the Arabidopsis (Arabidopsis thaliana) snd1 nst1 double mutant effectively complemented the secondary wall defects in fibers, indicating that PtrWNDs are capable of activating the entire secondary wall biosynthetic program. Overexpression of PtrWND2B and PtrWND6B in Arabidopsis induced the expression of secondary wall-associated transcription factors and secondary wall biosynthetic genes and, concomitantly, the ectopic deposition of cellulose, xylan, and lignin. Furthermore, PtrWND2B and PtrWND6B were able to activate the promoter activities of a number of poplar wood-associated transcription factors and wood biosynthetic genes. Together, these results demonstrate that PtrWNDs are functional orthologs of SND1 and suggest that PtrWNDs together with their downstream transcription factors form a transcriptional network involved in the regulation of wood formation in poplar.


Assuntos
Proteínas de Plantas/metabolismo , Populus/genética , Fatores de Transcrição/metabolismo , Madeira/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Parede Celular/genética , Parede Celular/metabolismo , Celulose/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Teste de Complementação Genética , Lignina/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Populus/metabolismo , Regiões Promotoras Genéticas , RNA de Plantas/genética , Fatores de Transcrição/genética , Ativação Transcricional , Madeira/metabolismo , Xilanos/metabolismo
14.
Mater Sci Eng C Mater Biol Appl ; 118: 111527, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255080

RESUMO

A novel nanodrug delivery system (NDDS) based on block copolymers of Poly(DEA)-block-Poly(PgMA) (PDPP) was developed to enhance in vitro cellular uptake and anticancer efficacy. pH-responsive doxorubicin (DOX) based small molecule prodrug (DOX-hyd-N3) and mPEG-N3 were co-conjugated onto PDPP via copper-catalyzed "Click chemistry" to give a dual pH-responsive polymeric prodrug (mPEG-g-PDPP-g-hyd-DOX), which could be self-assembled into core-shell polymeric micelles (M(DOX)) with particles size of 81 ± 1 nm in aqueous phase. Additionally, the pH-responsive charge-reversal, stability and drug release behaviour at different pHs were then evaluated. Moreover, the surface charge of M(DOX) could quickly convert from negative (-6.64 ± 3.37 mV) to positive (5.35 ± 1.33 mV) thanks to the protonation of Poly(DEA) moieties as the pH value decreased from 7.4 during blood circulation to 6.5 in extracellular of tumour tissues. Meanwhile, according to the cytotoxicity determined by CCK-8 assay, cellular uptake, flow-cytometric and apoptosis profiles of two human cancer cell lines (HeLa and SW480), we could draw the conclusion that the cellular uptake and anticancer efficacy were significantly enhanced when cells were incubated with micelles at pH 6.5 due to the charge-reversal of micelles from negative to positive. With the protonation of Poly(DEA) moieties in acidic extracellular microenvironment and the pH-responsive DOX release with hydrazone linkage in endo/lysosome pH, this dual pH-responsive-charge-reversal micelle platform might become an encouraging strategy for more effective cancer treatment.


Assuntos
Doxorrubicina , Micelas , Doxorrubicina/farmacologia , Portadores de Fármacos , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Polímeros
15.
Huan Jing Ke Xue ; 42(1): 204-210, 2021 Jan 08.
Artigo em Zh | MEDLINE | ID: mdl-33372472

RESUMO

Micro-plastics (MPs) pollution has been a hotspot in soil environment. To explore the correlation of the vegetation cover and the distribution of MPs in Yellow River Delta wetland, the characters of MPs in the soil sampled at 16 sites where reed (Phragmites communis, a low-salt dominant species) and Suaeda salsa (a high-salt dominant species) covered were investigated. The abundance of MPs here ranged to 80-4640 n·kg-1, and the particle size ranged to 13 µm-5 mm. The main components of MPs with large size were polyethylene (PE), polyethylene terephthalate (PET) and polystyrene (PS), and the content of PET ranged to 0.22-1.16 µg·kg-1. The barrier effect of reed on MPs was higher than that of Suaeda salsa. The average abundance of MPs and PET contents at the sites where reed covered were 1423 n·kg-1 and 0.62 µg·kg-1, and they mainly consisted of small particles with a size less than 50 µm. The average abundance of MPs and PET contents at the site Suaeda salsa covered were 584 n·kg-1 and 0.33 µg·kg-1, and they mainly consisted of fragments and fibers with a size ranged to 100-1000 µm. The abundance of MPs in the soil was significantly correlated with the growth statues of the vegetations (P=0.001). Therefore, the distribution of MPs in the soil in the same area covered by different vegetation might be spatial different.


Assuntos
Rios , Áreas Alagadas , China , Microplásticos , Plásticos , Solo
16.
Plant Cell Physiol ; 51(6): 1084-90, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20427511

RESUMO

Dicot wood is mainly composed of cellulose, xylan and lignin, and its formation requires the coordinated regulation of their biosynthesis. In this report, we demonstrate that the poplar wood-associated MYB transcriptional activators, PtrMYB3 and PtrMYB20, activate the biosynthetic pathways of cellulose, xylan and lignin when overexpressed in Arabidopsis and they are also able to activate the promoter activities of poplar wood biosynthetic genes. We also show that PtrMYB3 and PtrMYB20 are functional orthologs of Arabidopsis MYB46 and MYB83, and their expression is directly activated by poplar PtrWND2, suggesting their involvement in the regulation of wood formation in poplar.


Assuntos
Parede Celular/metabolismo , Celulose/biossíntese , Proteínas de Plantas/metabolismo , Populus/genética , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Genes myb , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Populus/metabolismo , Regiões Promotoras Genéticas , RNA de Plantas/genética , Fatores de Transcrição/genética , Madeira/genética , Madeira/crescimento & desenvolvimento
17.
Wound Repair Regen ; 18(1): 70-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20082682

RESUMO

In situ photopolymerized hydrogel dressings create minimally invasive methods that offer advantages over the use of preformed dressings such as conformability in any wound bed, convenience of application, and improved patient compliance and comfort. Here, we report an in situ-formed hydrogel membrane through ultraviolet cross-linking of a photocross-linkable azidobenzoic hydroxypropyl chitosan aqueous solution. The hydrogel membrane is stable, flexible, and transparent, with a bulk network structure of smoothness, integrity, and density. Fluid uptake ability, water vapor transmission rate, water retention, and bioadhesion of the thus resulted hydrogel membranes (0.1 mm thick) were determined to range from 97.0-96.3%, 2,934-2,561 g/m(2)/day, 36.69-22.94% (after 6 days), and 4.8-12.3 N/cm(2), respectively. These data indicate that the hydrogel membrane can maintain a long period of moist environment over the wound bed for enhancing reepithelialization. Specifically, these properties of the hydrogel membrane were controllable to some extent, by adjusting the substitution degree of the photoreactive azide groups. The hydrogel membrane also exhibited barrier function, as it was impermeable to bacteria but permeable to oxygen. In vitro experiments using two major skin cell types (dermal fibroblast and epidermal keratinocyte) revealed the hydrogel membrane have neither cytotoxicity nor an effect on cell proliferation. Taken together, the in situ photocross-linked azidobenzoic hydroxypropyl chitosan hydrogel membrane has a great potential in the management of wound healing and skin burn.


Assuntos
Bandagens , Materiais Biocompatíveis , Quitosana , Hidrogel de Polietilenoglicol-Dimetacrilato , Raios Ultravioleta , Adesividade , Animais , Bandagens/efeitos adversos , Bandagens/microbiologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Reagentes de Ligações Cruzadas , Humanos , Membranas Artificiais , Permeabilidade , Pele , Suínos , Perda Insensível de Água , Cicatrização
18.
Biomaterials ; 262: 120300, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32891908

RESUMO

The tumor/infection-impaired skin regeneration is still a challenge and the single modal therapy strategy is usually inefficient. Herein, a multimodal tumor therapy and antiinfection method based on the conductive multifunctional poly(glycerol-amino acid)-based scaffolds is reported. The multifunctional conductive scaffolds were formed through the crosslinking between branched poly(glycerol-amino acid), polypyrrole@polydopamine (PPy@PDA) nanoparticles and aldehyde F127 (PGFP scaffolds). PGFP scaffolds possessed controlled electrical conductivity, skin-adhesive behavior, broad-spectrum antibacterial activity, photothermal-responsive drug release and good cytocompatibility. Thus, PGFP scaffolds demonstrated the significant photothermo-chemo tumor and multidrug resistant infection therapy in vitro and in vivo, while promoting granulation tissue formation, collagen deposition, vascular endothelial differentiation and accelerated skin regeneration. This work also firstly demonstrated the important role of multifunctional conductive PPy@PDA nanoparticles in tumor/infection-impaired skin multimodal therapy. This study suggests that efficient multimodal therapy on diseased-impaired skin could be achieved through optimizing the structure and multifunctional properties of biomaterials.


Assuntos
Polímeros , Pirróis , Aminoácidos , Condutividade Elétrica , Glicerol
19.
Int J Pharm ; 581: 119239, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32194211

RESUMO

We induced changes in the tumor microenvironment (TME) through the synergistic actions of two drugs used in breast cancer therapy. The anti-fibrotic drug silibinin (SLB) targets tumor-associated fibroblasts and exerts immune-mediated anti-cancer effects. IPI-549, an efficient and highly selective phosphoinositide-3-kinase-gamma (PI3Kγ) inhibitor, was applied to alter the balance of immunosuppressive cells by inhibiting PI3Kγ molecules; it also promotes anti-tumor immunity. We developed nanoparticle formulations to encapsulate both drugs into the targeting carrier aminoethyl anisamide-polyethylene glycol-polycaprolactone (AEAA-PEG-PCL) respectively. The drugs were intravenously delivered in mice and resulted in an increase in anti-tumor efficacy and apoptotic tumor tissue compared with either IPI-549 or SLB alone in 4T1 breast cancer cell-derived tumors. Furthermore, a significant reduction in regulatory T (Treg) cells and myeloid suppressor cells (MDSCs) was observed. A normalized TME structure was also observed, including angiogenesis suppression, antifibrotic effects and the inhibition of collagen formation in the tumor tissue, significantly enhancing the anti-tumor effects. In summary, this combination strategy may offer an alternative treatment for breast cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Portadores de Fármacos/química , Isoquinolinas/administração & dosagem , Pirazóis/administração & dosagem , Pirimidinas/administração & dosagem , Silibina/administração & dosagem , Administração Intravenosa , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Benzamidas/química , Neoplasias da Mama/patologia , Fibroblastos Associados a Câncer , Linhagem Celular Tumoral/transplante , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Feminino , Humanos , Isoquinolinas/farmacocinética , Camundongos , Nanopartículas/química , Poliésteres/química , Polietilenoglicóis/química , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacocinética , Pirazóis/farmacocinética , Pirimidinas/farmacocinética , Silibina/farmacocinética , Microambiente Tumoral/efeitos dos fármacos
20.
J Hazard Mater ; 382: 121091, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472465

RESUMO

In this study, we proposed to apply an integrated process which is comprised of in situ ozonation, ceramic membrane filtration (CMF) and biologically active carbon (BAC) filtration to wastewater reclamation for indirect potable reuse purpose. A pilot-scale (20 m3/d) experiment had been run for ten months to validate the prospect of the process in terms of treatment performance and operational stability. Results showed that the in situ O3 + CMF + BAC process performed well in pollutant removal, with chemical oxygen demand, ammonia, nitrate nitrogen, total phosphorus and turbidity levels in the treated water being 5.1 ±â€¯0.9, 0.05 ±â€¯0.01, 10.5 ±â€¯0.8, <0.06 mg/L, and <0.10 NTU, respectively. Most detected trace organic compounds were degraded by>96%. This study demonstrated that synergistic effects existed in the in situ O3 + CMF + BAC process. Compared to pre-ozonation, in situ ozonation in the membrane tank was more effective in controlling membrane fouling (maintaining operational stability) and in degrading organic pollutants, which could be attributed to the higher residual ozone concentration in the tank. Because of the removal of particulate matter by CMF, water head loss of the BAC filter increased slowly and prolonged the backwashing interval to 30 days. BAC filtration was also effective in removing ammonia and N-nitrosodimethylamine from the ozonated water.


Assuntos
Carvão Vegetal/química , Filtração/métodos , Oxidantes/química , Ozônio/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Amônia/química , Cafeína/química , Cerâmica , DEET/química , Diterpenos/química , Membranas Artificiais , Nitrogênio/química , Fósforo/química , Teofilina/química , Águas Residuárias
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