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1.
BMC Musculoskelet Disord ; 25(1): 368, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730497

RESUMO

BACKGROUND: This systemic review and meta-analysis aimed to evaluate the clinical outcomes of proximal humeral fracture in elderly patient fixation using locked plate with or without cement augmentation. METHODS: The databases of PubMed, Embase, and Cochrane Library were searched in August 2023 for literature comparing the clinical outcomes of patients with PHFs treated with locked plate alone and locked plate augmented with cement. Data describing study design; level of evidence; inclusion criteria; demographic information; final follow-up; revision rate; implant failure rate; avascular necrosis rate; total complication rate; constant score; and disability of arm, shoulder, and hand (DASH) score were collected. RESULTS: Eight studies (one randomized-controlled trial and seven observational studies), involving 664 patients, were identified. Compared with locked plates alone, using cement-augmented locked plates reduced the implant failure rate (odds ratio (OR) = 0.19; 95% confidence interval (CI) 0.10-0.39; P < 0.0001) and total complication rate (OR = 0.45; 95% CI 0.29-0.69; P = 0.0002) and improved DASH scores (mean difference (MD) = 2.99; 95% CI 1.00-4.98; P = 0.003). However, there was no significant difference in clinical outcomes, including revision rate, avascular necrosis rate, and constant score. CONCLUSION: In this review and meta-analysis, fixation of the PHFs in elderly patients using locked plates with or without cement augmentation has no significant difference in revision rate, but the implant failure and total complication rates may be lesser on using the cement-augmented locked plate for fixation than on using a locked plate alone. Good results are expected for most patients treated with this technique. TRIAL REGISTRATION: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)21 guidelines were followed to conduct this systematic review and meta-analysis and was registered as a protocol in PROSPERO (CRD42022318798).


Assuntos
Cimentos Ósseos , Placas Ósseas , Fixação Interna de Fraturas , Fraturas do Ombro , Humanos , Fraturas do Ombro/cirurgia , Fraturas do Ombro/diagnóstico por imagem , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/efeitos adversos , Cimentos Ósseos/uso terapêutico , Cimentos Ósseos/efeitos adversos , Idoso , Resultado do Tratamento , Idoso de 80 Anos ou mais , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Reoperação
2.
BMC Oral Health ; 24(1): 515, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698359

RESUMO

OBJECTIVE: Low impacted third molars are usually asymptomatic and are often found by X-ray examination. The removal of asymptomatic low impacted third molars is one of the most controversial clinical issues in oral and maxillofacial surgery. METHODS: In this study, 806 patients with low impacted mandibular third molars (LIMTMs) (full bony impaction) were analyzed to determine the prevalence and risk factors for cystic lesions and adjacent tooth root resorption throughout the patients' entire life cycle. RESULTS: The results showed that the prevalence of adjacent tooth root resorption and cystic lesions was age-related, exhibiting a trend of first increasing and then decreasing; prevalence peaked at the age of 41 to 45 years old, the prevalence rates were 12.50% and 11.11% respectively. And the lowest prevalence rate was 2.86% and 2.44% in ≥ 61 group and 56- to 60-year age group respectively. Age was an independent risk factor for adjacent tooth root resorption of LIMTMs, whereas age and impaction type (especially inverted impaction) were independent risk factors for cystic lesions. CONCLUSIONS: The full life cycle management strategy for LIMTMs may need to be individualized. Surgical removal is recommended for LIMTMs in patients younger than 41 to 45 years, especially for inverted, mesioangular, and horizontally impacted LIMTMs. LIMTMs in patients older than 41 to 45 years may be treated conservatively with regular follow-up, but surgical removal of inverted impacted LIMTMs is still recommended to avoid cyst formation.


Assuntos
Dente Serotino , Reabsorção da Raiz , Dente Impactado , Humanos , Dente Impactado/complicações , Dente Impactado/diagnóstico por imagem , Reabsorção da Raiz/etiologia , Feminino , Estudos Retrospectivos , Masculino , Adulto , Pessoa de Meia-Idade , Fatores de Risco , Mandíbula , Prevalência , Adulto Jovem , Adolescente , Fatores Etários , Idoso
3.
Anal Chem ; 95(15): 6303-6311, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37014207

RESUMO

Ferroptosis is an iron-dependent process that regulates cell death and is essential for maintaining normal cell and tissue survival. The explosion of reactive oxygen species characterizes ferroptosis in a significant way. Peroxynitrite (ONOO-) is one of the endogenous reactive oxygen species. Abnormal ONOO- concentrations cause damage to subcellular organelles and further interfere with organelle interactions. However, the proper conduct of organelle interactions is critical for cellular signaling and the maintenance of cellular homeostasis. Therefore, investigating the effect of ONOO- on organelle interactions during ferroptosis is a highly attractive topic. To date, it has been challenging to visualize the full range of ONOO- fluctuations in mitochondria and lysosomes during ferroptosis. In this paper, we constructed a switchable targeting polysiloxane platform. During the selective modification of NH2 groups located in the side chain, the polysiloxane platform successfully constructed fluorescent probes targeting lysosomes and mitochondria (Si-Lyso-ONOO, Si-Mito-ONOO), respectively. Real-time detection of ONOO- in lysosomes and mitochondria during ferroptosis was successfully achieved. Remarkably, the occurrence of autophagy during late ferroptosis and the interaction between mitochondria and lysosomes was observed via the differentiated responsive strategy. We expect that this switchable targeting polysiloxane functional platform will broaden the application of polymeric materials in bioimaging and provide a powerful tool for further deeper understanding of the ferroptosis process.


Assuntos
Ferroptose , Siloxanas , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo , Lisossomos/química , Corantes Fluorescentes/química , Ácido Peroxinitroso/análise
4.
BMC Plant Biol ; 23(1): 44, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658483

RESUMO

BACKGROUND: Testa color is an important trait of peanut (Arachis hypogaea L.) which is closely related with the nutritional and commercial value. Pink and red are main color of peanut testa. However, the genetic mechanism of testa color regulation in peanut is not fully understood. To elucidate a clear picture of peanut testa regulatory model, samples of pink cultivar (Y9102), red cultivar (ZH12), and two RNA pools (bulk red and bulk pink) constructed from F4 lines of Y9102 x ZH12 were compared through a bulk RNA-seq approach. RESULTS: A total of 2992 differential expressed genes (DEGs) were identified among which 317 and 1334 were up-regulated and 225 and 1116 were down-regulated in the bulk red-vs-bulk pink RNA pools and Y9102-vs-ZH12, respectively. KEGG analysis indicates that these genes were divided into significantly enriched metabolic pathways including phenylpropanoid, flavonoid/anthocyanin, isoflavonoid and lignin biosynthetic pathways. Notably, the expression of the anthocyanin upstream regulatory genes PAL, CHS, and CHI was upregulated in pink and red testa peanuts, indicating that their regulation may occur before to the advent of testa pigmentation. However, the differential expression of down-stream regulatory genes including F3H, DFR, and ANS revealed that deepening of testa color not only depends on their gene expression bias, but also linked with FLS inhibition. In addition, the down-regulation of HCT, IFS, HID, 7-IOMT, and I2'H genes provided an alternative mechanism for promoting anthocyanin accumulation via perturbation of lignin and isoflavone pathways. Furthermore, the co-expression module of MYB, bHLH, and WRKY transcription factors also suggested a fascinating transcriptional activation complex, where MYB-bHLH could utilize WRKY as a co-option during the testa color regulation by augmenting anthocyanin biosynthesis in peanut. CONCLUSIONS: These findings reveal candidate functional genes and potential strategies for the manipulation of anthocyanin biosynthesis to improve peanut varieties with desirable testa color.


Assuntos
Antocianinas , Arachis , Antocianinas/metabolismo , Arachis/genética , Arachis/metabolismo , Redes Reguladoras de Genes , Lignina/metabolismo , Pigmentação/genética , Regulação da Expressão Gênica de Plantas , Cor , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica
5.
Cells Tissues Organs ; 212(4): 317-326, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35344952

RESUMO

Periodontal ligament stem cells (PDLSCs) possess self-renewal and multilineage differentiation potential and exhibit great potential for the treatment of bone tissue defects caused by inflammation. Previous studies have indicated that static magnetic field (SMF) can enhance the proliferation and differentiation of mesenchymal stem cells (MSCs). SMF has been widely used to repair bone defects and for orthodontic and implantation treatment. In this study, we revealed that a 320 mT SMF upregulates the protein expression levels of cytokines such as MCM7 and PCNA in proliferating PDLSCs. Cell counting kit-8 results revealed that the SMF group had higher optical density values than the control group. The ratio of cells in the S phase to those in the G2/M phase was significantly increased after exposure to a 320 mT SMF. In scratch assays, the SMF-treated PDLSCs exhibited a higher migration rate than the sham-exposed group after 24 h of culture, indicating that the SMF promoted the migratory ability of PDLSCs. The activity level of the early differentiation marker alkaline phosphatase and the late marker matrix mineralization, as well as osteoblast-specific gene and protein expression, were enhanced in PDLSCs exposed to the SMF. Furthermore, AKT signaling pathway was activated by SMF. Our data demonstrated that the potential mechanism of action of SMF may enhance PDLSCs proliferation and osteogenic differentiation by activating the phosphorylated AKT pathway. The elucidation of this molecular mechanism may lead to a better understanding of bone repair responses and aid in improved stem cell-mediated regeneration.


Assuntos
Osteogênese , Proteínas Proto-Oncogênicas c-akt , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ligamento Periodontal/metabolismo , Células Cultivadas , Diferenciação Celular , Células-Tronco , Proliferação de Células
6.
J Nanobiotechnology ; 21(1): 395, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37899463

RESUMO

Radiotherapy (RT) plays an important role in tumor therapy due to its noninvasiveness and wide adaptation. In recent years, radiation therapy has been discovered to induce an anti-tumor immune response, which arouses widespread concern among scientists and clinicians. In this review, we highlight recent advances in the applications of nano-biomaterials for radiotherapy-activated immunotherapy. We first discuss the combination of different radiosensitizing nano-biomaterials and immune checkpoint inhibitors to enhance tumor immune response and improve radiotherapy efficacy. Subsequently, various nano-biomaterials-enabled tumor oxygenation strategies are introduced to alleviate the hypoxic tumor environment and amplify the immunomodulatory effect. With the aid of nano-vaccines and adjuvants, radiotherapy refreshes the host's immune system. Additionally, ionizing radiation responsive nano-biomaterials raise innate immunity-mediated anti-tumor immunity. At last, we summarize the rapid development of immune modulatable nano-biomaterials and discuss the key challenge in the development of nano-biomaterials for tumor radio-immunotherapy. Understanding the nano-biomaterials-assisted radio-immunotherapy will maximize the benefits of clinical radiotherapy and immunotherapy and facilitate the development of new combinational therapy modality.


Assuntos
Materiais Biocompatíveis , Neoplasias , Humanos , Neoplasias/radioterapia , Imunoterapia , Adjuvantes Imunológicos , Sistema Imunitário
7.
Clin Oral Investig ; 27(8): 4279-4288, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37326659

RESUMO

OBJECTIVES: Extraction of impacted mandibular third molars (IMTMs) is the most common surgery performed in the Department of Oral and Maxillofacial Surgery. Inferior alveolar nerve (IAN) injury is a rare but severe complication, and the risk is significantly higher in cases of IMTM near the inferior alveolar canal (IAC). The existing surgical method to extract such IMTMs is either not safe enough or is time-consuming. A better surgical design is needed. MATERIALS AND METHODS: From August 2019 to June 2022, 23 patients underwent IMTM extraction by Dr. Zhao at Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Nanjing University, and were found to have IMTMs in close proximity to the IAC. Due to high IAN injury risk, these patients underwent coronectomy-miniscrew traction to extract their IMTMs. RESULTS: The time between coronectomy-miniscrew insertion and complete removal of the IMTM was 32.65 ± 2.110 days, which was significantly shorter than that of traditional orthodontic traction. Two-point discrimination testing revealed no IAN injury, and no injury was reported by patients during follow-up. Other complications, such as severe swelling, severe bleeding, dry socket, and limited mouth opening, were not observed. Postoperative pain levels were not significantly higher in the coronectomy-miniscrew traction group than in the traditional IMTM extraction group. CLINICAL RELEVANCE: For IMTMs that are in close proximity to the IAC and must be extracted, coronectomy-miniscrew traction is a novel approach to minimize the risk of IAN injury in a less time-consuming way with a lower possibility of complications.


Assuntos
Dente Impactado , Traumatismos do Nervo Trigêmeo , Humanos , Canal Mandibular , Dente Serotino/cirurgia , Traumatismos do Nervo Trigêmeo/prevenção & controle , Traumatismos do Nervo Trigêmeo/etiologia , Extração Dentária/efeitos adversos , Tração/efeitos adversos , Mandíbula/cirurgia , Dente Impactado/cirurgia , Nervo Mandibular
8.
Biochem Biophys Res Commun ; 609: 39-47, 2022 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-35413538

RESUMO

In this study, a tooth extraction socket model was established in vivo, and Lv-YAP1-GFP, Lv-GFP or saline was injected locally into the extraction socket. Expression of markers of osteogenesis, osteoclastogenesis, adipogenesis, proliferation and apoptosis explore whether YAP can promote bone formation in the process of tooth extraction socket healing. 66 BALB/c mice were divided into 3 groups and underwent left maxillary first molar extraction, Lv-YAP1-GFP, Lv-GFP or saline was injected into the tooth extraction socket. The maxilla was harvested 1, 3, 7, and 10 days after operation for subsequent analysis by Micro-CT and immunohistochemical analysis. Quantitative analysis of the expression of TRAP, ALP, BMP2, RUNX2, Osterix, OCN, RANKL, PPARγ, and PCNA was conducted. The results of immunofluorescence showed that the lentivirus was successfully transfected into the extraction socket. On the middle and last stage of tooth extraction healing, results of Micro-CT showed that the BV/TV, Tb.Th and Tb.N were significantly higher in the experimental group, results of immunohistochemistry showed that the overexpression of YAP increase in the expression of BMP2, ALP, RUNX2, Osterix, OCN, and PCNA. The expression of PPARγ and TUNEL staining results were significantly lower in the experimental group. The expression of TRAP and RANKL showed no significant differences among the 3 groups. We conclude that YAP could promote bone formation in the middle and late stages of tooth extraction socket healing. The overexpression of YAP increased bone formation and cell proliferation, decreased adipogenic differentiation and apoptosis.


Assuntos
Subunidade alfa 1 de Fator de Ligação ao Core , Proteínas de Sinalização YAP , Animais , Camundongos , Osteogênese , PPAR gama , Antígeno Nuclear de Célula em Proliferação , Extração Dentária , Alvéolo Dental/cirurgia
9.
Macromol Rapid Commun ; 43(5): e2100720, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34962323

RESUMO

Nontraditional intrinsic luminescence (NTIL) which always accompanied with aggregation-induced emission (AIE) features has received considerable attention due to their importance in the understanding of basic luminescence principle and potential practical applications. However, the rational modulation of the NTIL of nonconventional luminophores remains difficult, on account of the limited understanding of emission mechanisms. Herein, the emission color of nonconjugated poly(methyl vinyl ether-alt-maleic anhydride) (PMVEMA) can be readily regulated from blue to red by controlling the alkalinity during the hydrolysis process. The nontraditional photoluminescence with AIE property is from the new formed p-band state, resulting from the strong overlapping of p orbitals of the clustered O atoms through space interactions. Hydrated hydroxide complexes embedded in the entangled polymer chain make big difference on the clustering of O atoms which dominates the AIE property of nonconjugated PMVEMA. These new insights into the photoluminescence mechanism of NTIL should stimulate additional experimental and theoretical studies and can benefit the molecular-level design of nontraditional chromophores for optoelectronics and other applications.


Assuntos
Luminescência , Polímeros , Hidróxidos , Anidridos Maleicos
10.
Int J Mol Sci ; 23(6)2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35328601

RESUMO

Delayed surface endothelialization is a bottleneck that restricts the further application of cardiovascular stents. It has been reported that the nature-inspired extracellular matrix (ECM) secreted by the hyaluronic acid (HA) micro-patterned smooth muscle cells (SMC) and endothelial cells (EC) can significantly promote surface endothelialization. However, this ECM coating obtained by decellularized method (dECM) is difficult to obtain directly on the surface of degradable magnesium (Mg) alloy. In this study, the method of obtaining bionic dECM by micro-patterning SMC/EC was further improved, and the nature-inspired ECM was prepared onto the Mg-Zn-Y-Nd (ZE21B) alloy surface by self-assembly. The results showed that the ECM coating not only improved surface endothelialization of ZE21B alloy, but also presented better blood compatibility, anti-hyperplasia, and anti-inflammation functions. The innovation and significance of the study is to overcome the disadvantage of traditional dECM coating and further expand the application of dECM coating to the surface of degradable materials and materials with different shapes.


Assuntos
Ligas , Células Endoteliais , Ligas/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Matriz Extracelular , Magnésio/farmacologia , Miócitos de Músculo Liso
11.
Cell Tissue Res ; 383(2): 809-821, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33159581

RESUMO

Stem cell transplantation is a promising therapy for wound healing, but the low retention and survival of transplanted stem cells limit their application. Injectable hydrogels exert beneficial effects in skin tissue engineering. In this study, an injectable hydrogel composed of sodium alginate (SA) and collagen type I (Col) was synthesized as a tissue scaffold to improve the efficacy of stem cells in a full-thickness excision wound model. Our results showed that SA/Col hydrogel was injectable, biodegradable, and exhibited low immunogenicity, which could promote the retention and survival of hUC-MSCs in vivo. SA/Col loaded with hUC-MSCs showed reduced wound size (p < 0.05). Histological and immunofluorescence results confirmed that SA/Col loaded with hUC-MSCs significantly promoted the formation of granulation, enhanced collagen deposition and angiogenesis, increased VEGF and TGF-ß1 expression (p < 0.05), and mitigated inflammation evidenced by lower production of TNF-α and IL-1ß and higher release of IL-4 and IL-10 (p < 0.05). Furthermore, SA/Col loaded with hUC-MSCs significantly lowered the expression of NLRP3 inflammasome-related proteins (p < 0.05). Taken together, our results suggest that SA/Col loaded with hUC-MSCs promotes skin wound healing via partly inhibiting NLRP3 pathway, which has potential to the treatment of skin wounds.


Assuntos
Alginatos/farmacologia , Colágeno/farmacologia , Hidrogéis/farmacologia , Células-Tronco Mesenquimais/citologia , Pele/efeitos dos fármacos , Cordão Umbilical/citologia , Cicatrização , Animais , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Inflamação/patologia , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
12.
Zhongguo Zhong Yao Za Zhi ; 45(4): 854-860, 2020 Feb.
Artigo em Zh | MEDLINE | ID: mdl-32237486

RESUMO

L_9(3~4) orthogonal experiment design was used to optimize the preparation of the patches,and investigate its affecting factors and skin irritation. Eugenol was taken as the index component to study the release behavior in vitro and percutaneous penetration of Cangai oil transfersomes patches by HPLC.The results showed that the optimal prescription for preparing Cangai oil transfersomes patches were Eudragit E100 0.6 g, succinic acid 0.08 g,triethyl citrate 0.25 g,glycerol 0.2 g.Patches prepared by the preferred preparation had a flat appearance without obvious bubbles.The initial adhesion was 18.33±2.52, the stickiness was(30.01±2.45) min,and the peel strength was(5.62±0.95) kN·m~(-1).The results of affecting factors experiment showed the order of factors affecting its adhesion was humidity>temperature>lighting,and the skin irritation test results showed no significant skin irritation after 24 h of single administration. The results of drug release behavior in vitro showed that the release and the percutaneous penetration of both Cangai oil patches and Cangai oil transfersomes patches conformed to the Higuchi equation.The release amount of eugenol were 80.66% and 82.25% at 72 h, with no significant difference. The cumulative permeation area of eugenol per unit area reached(0.195 6±0.065 9),(0.131 0±0.045 5) mg·cm~(-2) at 72 h, with significant differences(P<0.05).The experiment results proved that the preparation process of Cangai oil transfersomes patches was stable,and the prepared patches had a good adhesion. At the same time,the preparation of transfersomes patches could alleviate and control the release of the drug to a certain extent, and provide a certain experimental basis for clinical pediatric drug safety.


Assuntos
Óleos de Plantas/farmacologia , Absorção Cutânea , Pele/efeitos dos fármacos , Adesivo Transdérmico , Administração Cutânea , Portadores de Fármacos , Liberação Controlada de Fármacos , Humanos , Ácidos Polimetacrílicos
13.
Appl Microbiol Biotechnol ; 103(5): 2087-2099, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30661108

RESUMO

Bioethanol has been considered as a potentially renewable energy source, and metabolic engineering plays an important role in the production of biofuels. As an efficient ethanol-producing bacterium, Zymomonas mobilis has garnered special attention due to its high sugar uptake, ethanol yield, and tolerance. Different metabolic engineering strategies have been used to establish new metabolic pathways for Z. mobilis to broaden its substrate range, remove competing pathways, and enhance its tolerance to ethanol and lignocellulosic hydrolysate inhibitors. Recent advances in omics technology, computational modeling and simulation, system biology, and synthetic biology contribute to the efficient re-design and manipulation of microbes via metabolic engineering at the whole-cell level. In this review, we summarize the progress of some new technologies used for metabolic engineering to improve bioethanol production and tolerance in Z. mobilis. Some successful examples of metabolic engineering used to develop strains for ethanol production are described in detail. Lastly, some important strategies for future metabolic engineering efforts are also highlighted.


Assuntos
Biocombustíveis/microbiologia , Etanol/metabolismo , Lignina/metabolismo , Engenharia Metabólica/métodos , Zymomonas/metabolismo , Farmacorresistência Bacteriana/genética , Fermentação , Redes e Vias Metabólicas/genética , Zymomonas/genética
14.
Biomacromolecules ; 19(5): 1686-1696, 2018 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-29617128

RESUMO

Processive hydrolysis of crystalline cellulose by cellulases is a critical step for lignocellulose deconstruction. The classic Trichoderma reesei exoglucanase TrCel7A, which has a closed active-site tunnel, starts each processive run by threading the tunnel with a cellulose chain. Loop regions are necessary for tunnel conformation, resulting in weak thermostability of fungal exoglucanases. However, endoglucanase CcCel9A, from the thermophilic bacterium Clostridium cellulosi, comprises a glycoside hydrolase (GH) family 9 module with an open cleft and five carbohydrate-binding modules (CBMs) and hydrolyzes crystalline cellulose processively. How CcCel9A and other similar GH9 enzymes bind to the smooth surface of crystalline cellulose to achieve processivity is still unknown. Our results demonstrate that the C-terminal CBM3b and three CBMX2s enhance productive adsorption to cellulose, while the CBM3c adjacent to the GH9 is tightly bound to 11 glucosyl units, thereby extending the catalytic cleft to 17 subsites, which facilitates decrystallization by forming a supramodular binding surface. In the open cleft, the strong interaction forces between substrate-binding subsites and glucosyl rings enable cleavage of the hydrogen bonds and extraction of a single cellulose chain. In addition, subsite -4 is capable of drawing the chain to its favored location. Cellotetraose is released from the open cleft as the initial product to achieve high processivity, which is further hydrolyzed to cellotriose, cellobiose and glucose by the catalytic cleft of the endoglucanase. On this basis, we propose a wirewalking mode for processive degradation of crystalline cellulose by an endoglucanase, which provides insights for rational design of industrial cellulases.


Assuntos
Proteínas de Bactérias/química , Celulase/química , Celulose/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Celulase/genética , Celulase/metabolismo , Clostridium/enzimologia , Clostridium/genética , Hidrólise , Ligação Proteica
15.
J Nanosci Nanotechnol ; 18(7): 4464-4470, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442620

RESUMO

Cancer chemotherapy has limitations such as nonselective distribution of drugs, detrimental side effects on normal tissues; here we reported a smart pH and magnetic sensitive drug delivery system (DDS) based on PEGylated Fe3O4 superparamagnetic nanoparticles. The citric-coated Fe3O4 (CIO) nanoparticles were firstly synthesized and further functionalized by biocompatible poly(ethylene glycol) bis(carboxymethyl ether) (COOH-PEG-COOH), thus PEGylated CIO (GCIO) nanoparticles were obtained. Doxorubicin (DOX) was conjugated as a model drug to the nanoparticles via hydrazone bond. The roughly sphere GCIO nanoparticles were comparatively strong magnetism with high drug loading capability (~89%) in relatively uniform size. Drug release study revealed that the GCIO-DOX performed pH-responsive drug-release properties. MTT assay demonstrated that GCIO nanoparticles possessed low cytotoxicity and good physiological stability. Further, cell viability results indicated that the GCIO-DOX showed effective cytotoxicity only a bit lower than free DOX. All obtained data indicated that the combined pH-responsive and magnetic multifunction drug delivery system can has excellent potential applications in cancer therapy.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Nanopartículas , Concentração de Íons de Hidrogênio , Polietilenoglicóis
16.
Biomacromolecules ; 18(3): 778-786, 2017 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-28094989

RESUMO

Natural compounds glucosamine and cholic acid have been used to make acrylic monomers which are subsequently used to prepare amphiphilic block copolymers by reversible addition-fragmentation chain transfer (RAFT) polymerization. Despite the striking difference in polarity and solubility, three diblock copolymers consisting of glucosamine and cholic acid pendants with different hydrophilic and hydrophobic chain lengths have been synthesized without the use of protecting groups. They are shown to self-assemble into polymeric micelles with a "bitter" bile acid core and "sweet" sugar shell in aqueous solutions, as evidenced by dynamic light scattering and transmission electron microscopy. The critical micelle concentration varies with the hydrophobic/hydrophilic ratio, ranging from 0.62 to 1.31 mg/L. Longer chains of polymers induced the formation of larger micelles in range of 50-70 nm. These micelles can solubilize hydrophobic compounds such as Nile Red in aqueous solutions. Their loading capacity mainly depends upon the hydrophobic/hydrophilic ratio of the polymers, and may be also related to the length of the hydrophilic block. These polymeric micelles allowed for a 10-fold increase in the aqueous solubility of paclitaxel and showed no cytotoxicity below the concentration of 500 mg/L. Such properties make these polymeric micelles interesting reservoirs for hydrophobic molecules and drugs for biomedical applications.


Assuntos
Ácido Cólico/química , Glucosamina/química , Micelas , Polímeros/química , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/química , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Camundongos , Oxazinas/química , Paclitaxel/química , Polietilenoglicóis/química , Polimerização
17.
Biosci Biotechnol Biochem ; 81(3): 460-468, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27875934

RESUMO

White-rot basidiomycete Coriolopsis gallica HTC is one of the main biodegraders of poplar. In our previous study, we have shown the strong capacity of C. gallica HTC to degrade lignocellulose. In this study, equal amounts of total RNA fromC. Gallica HTC cultures grown in different conditions were pooled together. Illumina paired-end RNA sequencing was performed, and 13.2 million 90-bp paired-end reads were generated. We chose the Merged Assembly of Oases data-set for the following blast searches and gene ontology analyses. The reads were assembled de novo into 28,034 transcripts (≥ 100 bp) using combined assembly strategy MAO. The transcripts were annotated using Blast2GO. In all, 18,810 transcripts (≥100 bp) achieved BLASTX hits, of which, 7048 transcripts had GO term and 2074 had ECs. The expression level of 11 lignocellulolytic enzyme genes from the assembled C. gallica HTC transcriptome were detected by real-time quantitative polymerase chain reaction. The results showed that expression levels of these genes were affected by carbon source and nitrogen source at the level of transcription. The current abundant transcriptome data allowed the identification of many new transcripts in C. gallica HTC. Data provided here represent the most comprehensive and integrated genomic resources for cloning and identifying genes of interest from C. gallica HTC. Characterization of C. gallica HTC transcriptome provides an effective tool to understand mechanisms underlying cellular and molecular functions of C. gallica HTC.


Assuntos
Coriolaceae/enzimologia , Coriolaceae/genética , Enzimas/genética , Perfilação da Expressão Gênica/métodos , Regulação Fúngica da Expressão Gênica , Lignina/metabolismo , Enzimas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Ontologia Genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Lignina/genética , Fases de Leitura Aberta , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma
18.
J Mater Sci Mater Med ; 28(8): 125, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28707137

RESUMO

Esophageal cancer is difficult to cure globally and possesses high mortality rate, and it is generally accepted that palliative care such as stent implantation is the main therapy method for esophageal cancer in later period. However, the restenosis caused by tumor cells and inflammatory cells seriously interferes the stent clinical application and limits its long-term services. To solve this problem, series of drug delivery stents were developed and proven rather effective in the early stage of implantation, but more serious restenosis occurred after the drug delivery was over, which endangered the patients' life. Therefore, endowing the esophageal stent continuous anti-cancer function become an ideal strategy for inhibiting the restenosis. In this contribution, the functional layer composed of polydopamine (PDA) and Poly-ethylenimine (PEI) with series of molecular weights (MW, 1.8 × 103, 1 × 104, 2.5 × 104 and 7 × 104 Da) were fabricated onto the esophageal stent material 317L stainless steel (317L SS) surface. The surface characterization including amine quantitative, atomic force microscopy (AFM) and water contact angle measurement indicated successful preparation of the PDA/PEI layer. The Eca109 cells culture results proved that the PDA/PEI layers significantly improve Eca109 cells apoptosis and necrosis, suggesting excellent anti-cancer function. In addition, we also found that the anti-cancer function of the PDA/PEI layers was positively correlated to the immobilized PEIs' MW. All the results demonstrated the potential application of the PDA/PEI layers on the surface modification of esophageal stent for continuous anti-cancer function. It is generally accepted that the restenosis caused by tumor cells seriously interferes the esophageal stent clinical application. Thus, endowing the esophageal stent continuous anti-cancer function is the ideal strategy for inhibiting the restenosis. In this work, we fabricated functional layers composed of polydopamine (PDA) and Poly-ethylenimine (PEI) with series of molecular weights (MW, 1.8 × 103, 1 × 104, 2.5 × 104 and 7 × 104 Da) onto the esophageal stent material 317L stainless steel (317L SS) surface to inhibit the tumor cells growth, and this function was related to the PEIs' molecular weights. The functional PDA/PEI layers were expected potentially applied for surface modification of esophageal stent materials.


Assuntos
Antineoplásicos/administração & dosagem , Materiais Revestidos Biocompatíveis/química , Stents Farmacológicos , Neoplasias Esofágicas/tratamento farmacológico , Esôfago , Polietilenoimina/química , Antineoplásicos/farmacocinética , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Sistemas de Liberação de Medicamentos , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Esôfago/efeitos dos fármacos , Esôfago/metabolismo , Esôfago/patologia , Humanos , Indóis/química , Indóis/farmacologia , Teste de Materiais , Necrose/patologia , Polietilenoimina/farmacologia , Polímeros/química , Polímeros/farmacologia , Aço Inoxidável/química , Aço Inoxidável/farmacologia , Propriedades de Superfície , Água/metabolismo
19.
Gynecol Obstet Invest ; 82(5): 437-445, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27627757

RESUMO

BACKGROUND AND AIM: This study is aimed at investigating the tissue reactions of heterogenic and allogeneic acellular dermal matrix (ADM) mesh implanted in the vesicovaginal space in a rabbit model. METHODS: Twenty eight rabbits were implanted with heterogenic or allogeneic mesh, respectively, in the vesicovaginal space, and 4 served as the no-implantation control group. Rabbits were sacrificed at 7, 30, and 90 days after implantation. Histopathological study and immunohistochemical examination for collagen were performed. RESULTS: Heterogenic but not allogeneic mesh was identifiable at 90 days. In the allogeneic group, neovascularization was observed from day 7 after implantation. A chronic inflammatory reaction was noted in the heterogenic group at 30 days that decreased at 90 days. Inflammation was less in the allogeneic group, but giant cells and fibroblasts were present. With respect to collagen, the heterogenic mesh remained structurally unchanged at 90 days, while new collagen fibers were observed in the allogeneic group from day 7. CONCLUSION: The immunological outcomes of heterogenic and allogeneic ADM mesh are different. Heterogenic mesh induces a chronic inflammatory reaction at day 30 after implantation, and maintains its original form longer. Allogeneic mesh is associated with new collagen generation, but degrades earlier.


Assuntos
Derme Acelular , Materiais Biocompatíveis , Próteses e Implantes , Telas Cirúrgicas , Bexiga Urinária/imunologia , Vagina/imunologia , Animais , Colágeno/análise , Feminino , Fibroblastos , Humanos , Imuno-Histoquímica , Inflamação , Modelos Animais , Coelhos , Tolerância ao Transplante/imunologia , Bexiga Urinária/patologia , Vagina/patologia
20.
J Mater Sci Mater Med ; 27(4): 81, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26936367

RESUMO

The modification of cardiovascular stent surface for a better micro-environment has gradually changed to multi-molecule, multi-functional designation. In this study, heparin (Hep) and type IV collagen (IVCol) were used as the functional molecule to construct a bifunctional micro-environment of anticoagulation and promoting endothelialization on titanium (Ti). The surface characterization results (AFM, Alcian Blue 8GX Staining and fluorescence staining of IVCol) indicated that the bio-layer of Hep and IVCol were successfully fabricated on the Ti surface through electrostatic self-assembly. The APTT and platelet adhesion test demonstrated that the bionic layer possessed better blood compatibility compared with Ti surface. The adhesion, proliferation, migration and apoptosis tests of endothelial cells proved that the Hep/IVCol layer was able to enhance the endothelialization of the Ti surface. The in vivo animal implantation results manifested that the bionic surface could encourage new endothelialization. This work provides an important reference for the construction of multifunction micro-environment on the cardiovascular scaffold surface.


Assuntos
Colágeno Tipo IV/fisiologia , Heparina/química , Titânio/química , Animais , Materiais Biocompatíveis , Colágeno Tipo IV/química , Cães , Células Endoteliais/fisiologia , Artéria Femoral , Heparina/fisiologia , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Propriedades de Superfície
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