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1.
Transgenic Res ; 31(2): 215-225, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35133564

RESUMO

In this study, a novel laccase gene, EuLAC1, was cloned from Eucommia ulmoides Oliver (E. ulmoides). An overexpression vector harboring the EuLAC1 was constructed and introduced into the tobacco (Nicotiana tabacum cv. Xanthi). The laccase activity, resistance to Botrytis cinerea (B. cinerea) and lignin level in wild-type and transgenic plants were thereafter investigated. Interestingly, the transgenic tobacco displayed a significantly higher laccase activity and resistance to gray mold as compared to the wild-type tobacco. Additionally, the lignin contents in the leaves and stems of the transgenic tobacco were significantly higher in comparison to the wild-type tobacco. Scanning electron microscopy was used to observe the cross sections of wild-type and transgenic tobacco stems and it was noted that the cell wall near the xylem catheter of the transgenic tobacco was substantially thicker and the outline clearer than that of the wild-type. Thus, the EuLAC1 gene can significantly increase laccase activity and lignin content in tobacco, leading to an increase in the physical defenses, thereby increasing tobacco resistance to gray mold.


Assuntos
Lacase , Lignina , Botrytis/genética , Lacase/genética , Lignina/genética , Doenças das Plantas/genética , Plantas Geneticamente Modificadas/genética , Nicotiana/genética
2.
J Nanobiotechnology ; 17(1): 125, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31870362

RESUMO

BACKGROUND: Multidrug resistance (MDR) is a pressing obstacle in clinical chemotherapy for breast cancer. Based on the fact that the drug efflux is an important factor in MDR, we designed a codelivery system to guide the drug efflux inhibitor verapamil (VRP) and the chemotherapeutic agent novantrone (NVT) synergistically into breast cancer cells to reverse MDR. RESULTS: This co-delivery system consists of following components: the active targeting peptide RGD, an inorganic calcium phosphate (CaP) shell and an organic inner core. VRP and NVT were loaded into CaP shell and phosphatidylserine polyethylene glycol (PS-PEG) core of nanoparticles (NPs) separately to obtain NVT- and VRP-loaded NPs (NV@CaP-RGD). These codelivered NPs allowed VRP to prevent the efflux of NVT from breast cancer cells by competitively combining with drug efflux pumps. Additionally, NV@CaP-RGD was effectively internalized into breast cancer cells by precise delivery through the effects of the active targeting peptides RGD and EPR. The pH-triggered profile of CaP was also able to assist the NPs to successfully escape from lysosomes, leading to a greatly increased effective intracellular drug concentration. CONCLUSION: The concurrent administration of VRP and NVT by organic/inorganic NPs is a promising therapeutic approach to reverse MDR in breast cancer.


Assuntos
Antineoplásicos/química , Neoplasias da Mama/tratamento farmacológico , Mitoxantrona/química , Nanocápsulas/química , Verapamil/química , Animais , Fosfatos de Cálcio/química , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Sobrevivência Celular , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Quimioterapia Combinada/métodos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitoxantrona/farmacologia , Terapia de Alvo Molecular , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Fosfatidilserinas/química , Polietilenoglicóis/química , Verapamil/metabolismo
3.
Bioresour Technol ; 394: 130268, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154737

RESUMO

The complexity of biomass components leads to significant variations in the performance of biomass-based carbon dots (CDs). To shed light on this matter, this study presents a comparative analysis of the fluorescence properties of CDs using pure cellulose, lignin, and protein as models. Three CDs showed different fluorescent properties, resulting from the structure difference and carbonization behavior in the hydrothermal. The relatively gentle thermal degradation of proteins allows the macromolecular structure of amino acids to be preserved. This preservation results in a more regular lattice structure, a larger sp2 domain size, and N-doping, which contribute to the highest quantum yield (QY) of 8.7% of the CDs. In contrast, cellulose undergoes more severe thermal degradation with large amounts of small molecules generated, resulting in the CDs with fewer surface defects, more irregular lattice structures, and lower QY. These results provide a guideline for the design of carbon dots from different biomass.


Assuntos
Celulose , Lignina , Celulose/química , Carbono/química , Biomassa , Fluorescência , Corantes , Corantes Fluorescentes/química
4.
J Clin Microbiol ; 51(11): 3560-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23966496

RESUMO

Sporadic hand, foot, and mouth disease (HFMD) outbreaks and other infectious diseases in recent years have frequently been associated with certain human enterovirus (HEV) serotypes. This study explored the prevalences and genetic characteristics of non-HEV71 and non-coxsackievirus A16 (CV-A16) human enterovirus-associated HFMD infections in Shenzhen, China. A total of 2,411 clinical stool specimens were collected from hospital-based surveillance for HFMD from 2008 to 2012. The detection of HEV was performed by real-time reverse transcription-PCR (RT-PCR) and RT-seminested PCR, and spatiotemporal phylogenetic analysis was performed based on the VP1 genes. A total of 1,803 (74.8%) strains comprising 28 different serotypes were detected. In the past 5 years, the predominant serotypes were HEV71 (60.0%), followed by CV-A16 (21.2%) and two uncommon serotypes, CV-A6 (13.0%) and CV-A10 (3.3%). However, CV-A6 replaced CV-A16 as the second most common serotype between 2010 and 2012. As an emerging pathogen, CV-A6 became as common a causative agent of HFMD as HEV71 in Shenzhen in 2012. Phylogenetic analysis revealed that little variation occurred in the Chinese HEV71 and CV-A16 strains. The genetic characteristics of the Chinese CV-A6 and CV-A10 strains displayed geographic differences. The CV-A6 and CV-A10 strains circulating in Shenzhen likely originated in Europe. It was found that human enteroviruses have a high mutation rate due to evolutionary pressure and frequent recombination (3.2 × 10(-3) to 6.4 ×10(-3) substitutions per site per year for HEV71, CV-A6, CV-A16, and CV-A10). Since certain serotypes are potential threats to the public health, this study provides further insights into the significance of the epidemiological surveillance of HFMD.


Assuntos
Enterovirus/classificação , Enterovirus/genética , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/virologia , Filogeografia , RNA Viral/genética , Pré-Escolar , China/epidemiologia , Enterovirus/isolamento & purificação , Evolução Molecular , Fezes/virologia , Feminino , Genótipo , Humanos , Lactente , Masculino , Epidemiologia Molecular , Dados de Sequência Molecular , Taxa de Mutação , Reação em Cadeia da Polimerase , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
5.
World J Clin Cases ; 10(27): 9768-9775, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36186189

RESUMO

BACKGROUND: Giant cellulitis-like Sweet syndrome (SS) is a rare subtype of SS, and reports of the combined histiocytoid type of pathology are scarce. Here, we report a case of SS with distinctive clinical presentations and which was difficult to distinguish from cellulitis. By sharing this case and a discussion of the related literature in detail, we aim to provide clinicians with new insights into the characteristics of histiocytoid giant cellulitis-like (HGC)-SS and the pathogenesis of SS. CASE SUMMARY: A 52-year-old male was admitted after experiencing progressive fatigue for 1 mo and tongue swelling with pain for 1 d. He was diagnosed with myelodysplastic syndrome (MDS) and angioneurotic edema of the tongue and floor of the mouth. However, 7 d after examination by sternal aspiration, a violaceous, tender, and swollen nodule developed at the site, with poorly demarcated erythema of the surrounding skin. Considering his profile of risk factors, the diagnosis of cellulitis was made and he was administered broad-spectrum antibiotics. When the lesion continued to worsen and he developed chills and fever, pathogenic and dermatopathological examination led to the diagnosis of HGC-SS. Treatment with prednisone led to the fever being relieved within 24 h and the skin lesion being resolved within 1 wk. The patient refused intensive treatment and was instead given thalidomide, erythropoietin, stanozolol, and supportive care. The prednisone was gradually tapered, with no signs of recurrence, but he died 2 mo later of severe pneumonia. CONCLUSION: HGC-SS demonstrates unique manifestation. SS and leukemia cutis share cytological origin. Myelofibrosis and SS are adverse prognostic factors for MDS.

6.
Mater Sci Eng C Mater Biol Appl ; 119: 111435, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33321582

RESUMO

Bio-absorbable Zn alloys have been attractive replacements for the traditionally permanent implants due to their reasonable mechanical strength and elongation, degradation rate, and biocompatibility. The hybridization addition of Mg and Ag elements could greatly improve the mechanical properties and antibacterial ability of Zn, respectively. In the present paper, in vivo biocompatibility for the Zn-0.05Mg-(0, 0.5, 1 wt%) Ag implants in New Zealand rabbit was qualitatively evaluated during the implantation periods of 4, 12, and 24 weeks. The blood serum biochemical parameters and in vivo integrity of the implants in the live rabbits were monitored by using clinical chemistry analyzing and X-ray radiographic imaging techniques during the implantation process, respectively. There is no great difference in the serum biochemical indicator between the implanted rabbits and the control group. Especially the levels of serum Zn and serum Mg normalize after implantation of 24 weeks. The interfacial adherence between the implants and newly formed bones, and the histopathological morphology of heart, liver, and kidney were observed morphologically under the microscope. The new bones formed and grew surrounding the implants after 12 weeks' post-operation, which were well joined with the original cortical bones after post-implantation of 24 weeks. The heart, liver and kidney were not negatively influenced as evidenced from the serum biochemical indicators and morphologies of the tissues. Zn-0.05Mg-(0, 0.5, 1 wt%) Ag alloys are proved to be in vivo biocompatible and potential candidates for the biodegradable medical implants.


Assuntos
Materiais Biocompatíveis , Prata , Implantes Absorvíveis , Ligas , Animais , Materiais Biocompatíveis/farmacologia , Teste de Materiais , Coelhos , Zinco
7.
World J Clin Cases ; 9(6): 1461-1468, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33644216

RESUMO

BACKGROUND: In general, atlantoaxial dislocation is rare due to the stability of the C1-C2 complex. Traumatic atlantoaxial dislocations are usually anterior and accompanied by odontoid fractures. Posterior atlantoaxial dislocations are rare, and complete posterior dislocation without associated fracture is even more rare. A case of early recurrence of posterior atlantoaxial dislocation without fracture being in therapy of first closed reduction and then open reduction has not been previously reported. CASE SUMMARY: A 45-year-old female presented with traumatic posterior atlantoaxial dislocation (TPAD) of C1-C2 without associated fractures, and Frankel Grade B spinal cord function. She was successfully managed by immediate closed reduction under skull traction. Unexpectedly, 17 d later, re-dislocation was discovered. On day 28, closed reduction was performed as before but failed. Then, open reduction and posterior internal fixation with autologous iliac bone grafts was performed. By 6 mo after surgery, atlantoaxial joint fusion was achieved, and neurological function had recovered to Frankel Grade E. At 12 mo follow-up, she had lost only 15° of cervical rotation, and atlantoaxial complex instability in joint flexing and extending were no longer observed under fluoroscopy. CONCLUSION: Early assessment of transverse ligament is critical for TPAD without fracture avoiding re-dislocation after closed reduction.

8.
Zhonghua Yi Xue Za Zhi ; 89(11): 777-81, 2009 Mar 24.
Artigo em Zh | MEDLINE | ID: mdl-19595109

RESUMO

OBJECTIVE: To compare the effects of different calcium sulfate pellets made by different methods in treating segmental defect of bone. METHODS: Eighty New Zealand white rabbits underwent cutting off a segment in the middle part of radius so as to establish models of radial segmental defect, and than were divided into 4 groups: Group A as control group, Group B with calcium sulfate pellet made by routine method implanted into the defect, Group C with chitosan coated pressed calcium sulfate pellet implanted into the defect, and Group D with chitosan coated pressed calcium sulfate pellet combined with recombinant human bone morphogenetic protein (rhBMP)-2 implanted into the defect: X-ray photography was done every 4 weeks to observe the new bone formation. Four, 8, and 12 weeks 5 rabbits from each group were killed. The defect segments with parts of normal bone at both ends were cut off to undergo fluorescence microscopy and biomechanic three point bending test. RESULTS: X-ray photography and histological examination showed that new bone formation of cortex and reconstruction of marrow cavity were seen in Groups D and C, especially in Group D. The new bone mineralization rate of Group D was significantly higher than that of Group C (P<0.05) which was significantly higher than that of Group B (P<0.01). The anti-bending strength ratio of Group D was (47.5%+/-2.1%, significantly higher than that of Group C [(39.6+/-1.7)%, F=125.3, P<0.01], and the anti-bending strength ratios of Groups D and C were both significantly higher than those of Groups B and A [(23.6+/-3.3)% and (21.3+/-2.7)%]. CONCLUSION: Chitosan coated pressed calcium sulfate pellet shows relatively higher anti-bending strength and slightly slower resorption that closely coincide with the growth rate of new bone. It can be used to restore segmental bone defect, and particularly when combined with rhBMP-2.


Assuntos
Regeneração Óssea , Substitutos Ósseos/uso terapêutico , Sulfato de Cálcio/uso terapêutico , Animais , Sulfato de Cálcio/farmacologia , Implantes de Medicamento , Consolidação da Fratura/efeitos dos fármacos , Regeneração Tecidual Guiada , Coelhos , Rádio (Anatomia)/cirurgia , Engenharia Tecidual/métodos
9.
Orthop Surg ; 11(2): 325-329, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30884151

RESUMO

Fractures of the tibia represent a common class of injuries in orthopedics. The blood supply to the tibia is poor due to the small subcutaneous muscle tissues inside. Consequently, the tibia is prone to delayed fracture healing and nonunion of the fracture after surgery. In this case, we used porous tantalum metal plate to treat nonunion of a tibial fracture and achieved satisfactory therapeutic effects. For the first time in the field, we used 3D printing technology to fabricate porous tantalum metal plates for the treatment of tibial fractures. The resulting porous tantalum metal exhibited excellent mechanical and biological properties, and improved the therapeutic effects for the treatment of a tibial fracture nonunion. Porous tantalum metal plates have great application potential as a new implant material for internal fixation.


Assuntos
Materiais Biocompatíveis , Placas Ósseas , Tantálio , Fraturas da Tíbia/cirurgia , Adulto , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Consolidação da Fratura , Humanos , Masculino , Impressão Tridimensional , Radiografia , Fraturas da Tíbia/diagnóstico por imagem
10.
Nanoscale ; 10(37): 17663-17670, 2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30206611

RESUMO

Zinc oxide (ZnO) often serves as protein microarray substrates owing to its outstanding fluorescence enhancement effect. However, the integration of functional substrates with microfluidic technology to detect cancer biomarkers still needs to be optimized and promoted, for example, the optimization of micro/nanostructure and hydrophilic modification strategies for fluorescence immunoassays. Here, ZnO nanorod arrays were constructed on the inner wall of glass capillaries through a microfluidic chemical method, and the electrostatic layer by layer self-assembly was applied to modify the nanorod array with hydrophilic polyelectrolyte-polyacrylic acid (PAA). The effects of the flow rate and the reagent concentration on the morphology of the ZnO nanorod array were investigated. The ZnO nanorod array-based glass capillary, prepared at 25 µL min-1 for 4 min with 50 mM Zn2+ in solution, showed a remarkable enhancement in fluorescence performance. In addition, the introduction of PAA suppressed the interference of nonspecific protein and improved the antibody loading capacity effectively. In the detection of carcinoembryonic antigen, the limit of detection reached 100 fg mL-1, which indicated that the ZnO@PAA nanorod array-based microfluidic device exhibits remarkable fluorescence detection performance towards protein markers and possesses potential to be applied to point-of-care diagnostics and high throughput cancer biomarker detection.


Assuntos
Resinas Acrílicas/química , Imunofluorescência , Dispositivos Lab-On-A-Chip , Nanotubos , Óxido de Zinco/química , Antígeno Carcinoembrionário/análise , Nanoestruturas
11.
J Interferon Cytokine Res ; 37(12): 522-530, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29172969

RESUMO

Interleukin (IL)-35 modulates the imbalance between regulatory T cells (Tregs) and T helper (Th) 17 cells, which played vital roles in the pathogenesis of autoimmune and infectious diseases. However, the role of Tregs/Th17 cell imbalance and the regulatory functions of IL-35 have remained largely unknown in enterovirus 71 (EV71)-induced hand, foot, and mouth disease (HFMD). In this study, a total of 47 HFMD patients (30 with mild HFMD and 17 with severe HFMD) and 13 healthy individuals were enrolled. The frequencies of CD4+CD25+CD127dim/- Tregs and CD4+IL-17+ Th17 cells, as well as IL-35 expression levels, were measured. Cellular proliferation and cytokine production was also determined in purified Tregs following recombinant IL-35 stimulation. An imbalance between Tregs and Th17 cells was observed in children with severe HFMD, which manifested as a reduction in the Tregs population and an elevation in the Th17 population. Serum IL-35 concentrations were also decreased in case of severe HFMD, which correlated with the Tregs:Th17 cell ratios. Recombinant IL-35 stimulation increased the proportion of Tregs, but downregulated that of Th17 cells. Treatment with IL-35 enhanced Tregs suppressive function and IL-35 and IL-10 expression, but reduced IL-22 secretion in both healthy individuals and those with severe HFMD. The Tregs:Th17 cell ratio was increased in the convalescent patients, however, a significant reduction in serum IL-35 was not observed. Our findings indicated that EV71 infection shifted the Tregs:Th17 cell ratio through IL-35 by downregulating inhibitory cytokine production and reducing the cell-to-cell contact inhibition of effector T cells. Regulation of IL-35 as it relates to the Tregs/Th17 balance may play a critical role in the pathogenesis of EV71-associated HFMD.


Assuntos
Enterovirus Humano A/imunologia , Doença de Mão, Pé e Boca/imunologia , Interleucinas/imunologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Proliferação de Células , Células Cultivadas , Pré-Escolar , Feminino , Doença de Mão, Pé e Boca/diagnóstico , Doença de Mão, Pé e Boca/patologia , Humanos , Masculino
12.
J Environ Sci (China) ; 15(5): 577-82, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14562914

RESUMO

The nitrogen-modified lignocelluloses(NML) produced under oxic ammoniation was metabolized by white rot fungus, NH4(+) -N was released, NO3(-) -N concentration was decreased and total nitrogen loss was blocked within incubation period. During releasing nitrogen from the metabolism of NML, white rot fungus cometabolized recalcitrant environmental pollutants and showed higher degradation capability. Results indicated that this NML complex colonized by white rot fungus might be effective with economic feasibility when they are applied into the vast field ecosystem, it might stabilize NH4+ nitrogen flux and bioremediate the polluted environmental sites.


Assuntos
Basidiomycota/metabolismo , Celulose/metabolismo , Poluentes Ambientais/metabolismo , Lignina/metabolismo , Nitrogênio/metabolismo , Amônia/metabolismo , Biodegradação Ambiental
13.
J Biomed Mater Res A ; 92(2): 641-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19235220

RESUMO

Macrophage receptor with collagenous structure (MARCO) is a scavenger receptor with a very limited expression in healthy tissues. It was hypothesized that foreign body wear debris induces it to participate in handling of implant-derived particles in human synovial membrane-like tissue around aseptically loosening total hip replacement implants. A DNA microarray study showed that MARCO was upregulated in human monocytes by polymethyl methacrylate particles in cell culture. MARCO mRNA and protein were strongly expressed in numerous CD68 positive macrophages and foreign body giant cells in interface membrane lining and stroma around cemented implants, but was only present in a few cells in synovial membrane from osteoarthritis patients. A 65-kDa MARCO-reactive band was only found in interface tissue extracts. This is the first work to show upregulation of MARCO mRNA by foreign bodies in vitro. This is paralleled in vivo as MARCO mRNA and protein were over-expressed in chronic foreign body synovitis. As scavenger receptor MARCO apparently participates in handling of wear particles, which due to their nondegradable, irritating nature initiate/perpetuate foreign body inflammation, and peri-implant osteolysis.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Próteses e Implantes , Falha de Prótese , Receptores Imunológicos/biossíntese , Membrana Sinovial/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Western Blotting , Cimentos Ósseos , Cães , Feminino , Imunofluorescência , Humanos , Hibridização In Situ , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Polimetil Metacrilato , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
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