Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Vet Sci ; 10(8)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37624304

RESUMO

Porcine circovirus 3 (PCV3) is an emerging virus first discovered in the United States in 2015, and since then, PCV3 has been found in many regions of the world, including America, Asia, and Europe. Although several PCV3 investigations have been carried out, there is a lack of knowledge regarding the pathogenicity of PCV3, mostly due to the limited number of PCV3 isolates that are readily available. In this study, PCV3-DB-1 was isolated in PK-15 cells and characterized in vitro. Electron microscopy revealed the presence of PCV-like particles, and in situ hybridization RNA analysis demonstrated the replication of PCV3 in PK-15 cell culture. Based on phylogenetic analysis of PCV3 isolates from the Heilongjiang province of China, PCV3-DB-1 with 24 alanine and 27 lysine in the Cap protein was originally isolated and determined to belong to the clade PCV3a.

2.
Front Genet ; 14: 1084869, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36999050

RESUMO

Background: Lung adenocarcinoma (LUAD) is the most frequently occurring lung cancer worldwide, with increasing death rates. It belongs to the non-small cell lung cancer (NSCLC) type and has a strong association with previous smoking history. Growing evidence has demonstrated the significance of adenosine-to-inosine RNA editing (ATIRE) dysregulation in cancer. The aim of the present study was to evaluate ATIRE events that might be clinically useful or tumorigenic. Methods: To explore survival-related ATIRE events in LUAD, its ATIRE profiles, gene expression data, and corresponding patients' clinical information were downloaded from the Cancer Genome Atlas (TCGA) and the synapse database. We evaluated 10441 ATIRE in 440 LUAD patients from the TCGA database. ATIRE profiles were merged with TCGA survival data. We selected prognostic ATIRE sites, using a univariate Cox analysis (p < 0.001). Cox proportional hazards regression and lasso regression analysis were used to determine survival-related ATIRE sites, create risk ratings for those sites, and build a prognostic model and a nomogram for assessing overall survival (OS). Six ATIRE sites were used in the prognostic model construction and patients were randomly divided into a validation cohort (n = 176) and a training cohort (n = 264). The "Pheatmap" program was used to create risk curves that included risk score, survival time, and expression of ATIRE sites. We also determined the clinical prediction model's discrimination. The decision curve analysis and the 1-, 2-, and 3-year corrective curves were simultaneously used to evaluate the nomogram. We also evaluated the relationship between the amount of ATIRE sites and host gene expression and the impact of ATIRE expression on transcriptome expression. Results: The pyroglutamyl-peptidase I (PGPEP1) chr19:18476416A > I, ankyrin repeat domain 36B pseudogene 1 (ANKRD36BP1) (dist = 3,795), T-box transcription factor (TBX19) (dist = 29815) chr1:168220463A > I, Syntrophin Beta 2 (SNTB2) chr16:69338598A > I, hook microtubule-tethering protein 3 (HOOK3) chr8:42883441A > I, NADH dehydrogenase flavoprotein 3 (NDUFV3) chr21:44329452A > I, and FK506-binding protein 11 (FKBP11) chr12:49316769A > I were used in the prognostic model construction. High levels of risk score were significantly associated with worse OS and progression-free survival. Tumour stage and risk score were related to OS in LUAD patients. The predictors were among the prognostic nomogram model's risk score, age, gender, and tumor stage. The calibration plot and C-index (0.718) demonstrated the significant accuracy of nomogram's predictions. ATIRE level was markedly elevated in tumor tissues and was highly variable between patients. Conclusion: Events involving ATIRE in LUAD were highly functional and clinically relevant. The RNA editing-based model provides a solid framework for further investigation of the functions of RNA editing in non-coding areas and may be used as a unique method for predicting LUAD survival.

3.
BMC Cancer ; 23(1): 47, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36639629

RESUMO

BACKGROUND: New concepts for a more effective anti-cancer therapy are urgently needed. Experimental flaws represent a major counter player of this development and lead to inaccurate and unreproducible data as well as unsuccessful translation of research approaches into clinics. In a previous study we have created epithelial cell cultures from head and neck squamous cell carcinoma (HNSCC) tissue. METHODS: We characterize primary cell populations isolated from human papillomavirus positive HNSCC tissue for their marker expression by RT-qPCR, flow cytometry, and immunofluorescence staining. Their sensitivity to MDM2-inhibition was measured using cell viability assays. RESULTS: Primary HNSCC cell cultures showed the delayed formation of spheroids at higher passages. These spheroids mimicked the morphology and growth characteristics of other established HNSCC spheroid models. However, expression of epithelial and mesenchymal markers could not be detected in these cells despite the presence of the HNSCC stem cell marker aldehyde dehydrogenase 1 family member A1. Instead, strong expression of B- and T-lymphocytes markers was observed. Flow cytometry analysis revealed a heterogeneous mixture of CD3 + /CD25 + T-lymphocytes and CD19 + B-lymphocytes at a ratio of 4:1 at passage 5 and transformed lymphocytes at late passages (≥ passage 12) with CD45 + CD19 + CD20 + , of which around 10 to 20% were CD3 + CD25 + CD56 + . Interestingly, the whole population was FOXP3-positive indicative of regulatory B-cells (Bregs). Expression of transcripts specific for the Epstein-Barr-virus (EBV) was detected to increase in these spheroid cells along late passages, and this population was vulnerable to MDM2 inhibition. HPV + HNSCC cells but not EBV + lymphocytes were detected to engraft into immunodeficient mice. CONCLUSIONS: In this study we present a primary cell culture of EBV-infected tumor-infiltrating B-lymphocytes, which could be used to study the role of these cells in tumor biology in future research projects. Moreover, by describing the detailed characteristics of these cells, we aim to caution other researchers in the HNSCC field to test for EBV-infected lymphocyte contaminations in primary cell cultures ahead of further experiments. Especially researchers who are interested in TIL-based adopted immunotherapy should exclude these cells in their primary tumor models, e.g. by MDM2-inhibitor treatment. BI-12-derived xenograft tumors represent a suitable model for in vivo targeting studies.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias de Cabeça e Pescoço , Humanos , Camundongos , Animais , Carcinoma de Células Escamosas de Cabeça e Pescoço , Herpesvirus Humano 4 , Linfócitos , Proliferação de Células , Técnicas de Cultura de Células
4.
Microbiol Spectr ; 10(6): e0321022, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36287014

RESUMO

Little is known about the damage to the important peripheral immune organ spleen caused by Streptococcus suis infection. In this study, we found that S. suis induced splenomegaly and lymphocyte disruption in spleens of mice. To explore the mechanism of splenic lesions induced by S. suis, we conducted further studies. The results showed that S. suis induced apoptosis in B cells, which is related to the cleavage of caspase-3 and caspase-8, but not the release of apoptosis-inducing factor (AIF). Thus, S. suis induced apoptosis in the spleen through caspase-dependent and AIF-independent pathways. Inflammation lesions induced in the spleen of infected mice were also investigated; we found macrophages increased in histopathological lesions of infected spleens from 12 h postinoculation to 7 days postinoculation (dpi), and the type of increased macrophages was M1 type by confocal microscopy, which can secrete proinflammatory cytokines. Meanwhile, inflammasome NLRP3 and caspase-1 were activated, and gasdermin D (GSDMD) was cleaved, which causes pyroptosis that may result in the release of numerous proinflammatory cytokines. What's more, the increase of p-JNK and p-p38 indicated that the MAPK pathway was also involved in the proinflammatory responses during S. suis infection, whereas anti-inflammatory responses in spleen were suppressed, with regulatory T cells (Tregs) upregulating at 1 dpi. Taken together, proinflammatory immune responses dominate in early infection, which induce splenomegaly and splenocyte apoptosis. This is the first report of mechanisms associated with S. suis-induced splenic lesions. IMPORTANCE Streptococcus suis serotype 2 is considered an emerging pathogen and represents a threat to humans and animals. The spleen is an important peripheral immune organ, and splenomegaly is a consequence of lesions and an important clinical indicator of S. suis infection. However, knowledge of the mechanisms underlying spleen lesions is still very limited. In the present work, we made the investigation to explain the phenomenon and the related immunomodulation in a mouse infection model. The obtained results show that inflammation contributes to splenomegaly, while apoptosis contributes to lymphocyte disruption in spleens. Related signaling pathways were discovered which have never been associated with S. suis-induced splenic injury. The new knowledge generated will help us better understand the mechanism of S. suis pathogenesis.


Assuntos
Baço , Streptococcus suis , Humanos , Animais , Camundongos , Esplenomegalia , Sorogrupo , Citocinas , Apoptose , Inflamação
5.
J Virol ; 96(20): e0131822, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36173190

RESUMO

Pseudorabies virus (PRV), which is extremely infectious and can infect numerous mammals, has a risk of spillover into humans. Virus-host interactions determine viral entry and spreading. Here, we showed that neuropilin-1 (NRP1) significantly potentiates PRV infection. Mechanistically, NRP1 promoted PRV attachment and entry, and enhanced cell-to-cell fusion mediated by viral glycoprotein B (gB), gD, gH, and gL. Furthermore, through in vitro coimmunoprecipitation (Co-IP) and bimolecular fluorescence complementation (BiFC) assays, NRP1 was found to physically interact with gB, gD, and gH, and these interactions were C-end Rule (CendR) motif independent, in contrast to currently known viruses. Remarkably, we illustrated that the viral protein gB promotes NRP1 degradation via a lysosome-dependent pathway. We further demonstrate that gB promotes NRP1 degradation in a furin-cleavage-dependent manner. Interestingly, in this study, we generated gB furin cleavage site (FCS)-knockout PRV (Δfurin PRV) and evaluated its pathogenesis; in vivo, we found that Δfurin PRV virulence was significantly attenuated in mice. Together, our findings demonstrated that NRP1 is an important host factor for PRV and that NRP1 may be a potential target for antiviral intervention. IMPORTANCE Recent studies have shown accelerated PRV cross-species spillover and that PRV poses a potential threat to humans. PRV infection in humans always manifests as a high fever, tonic-clonic seizures, and encephalitis. Therefore, understanding the interaction between PRV and host factors may contribute to the development of new antiviral strategies against PRV. NRP1 has been demonstrated to be a receptor for several viruses that harbor CendR, including SARS-CoV-2. However, the relationships between NRP1 and PRV are poorly understood. Here, we found that NRP1 significantly potentiated PRV infection by promoting PRV attachment and enhanced cell-to-cell fusion. For the first time, we demonstrated that gB promotes NRP1 degradation via a lysosome-dependent pathway. Last, in vivo, Δfurin PRV virulence was significantly attenuated in mice. Therefore, NRP1 is an important host factor for PRV, and NRP1 may be a potential target for antiviral drug development.


Assuntos
COVID-19 , Herpesvirus Suídeo 1 , Pseudorraiva , Camundongos , Humanos , Animais , Herpesvirus Suídeo 1/metabolismo , Neuropilina-1/genética , Neuropilina-1/metabolismo , Furina/metabolismo , SARS-CoV-2 , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Replicação Viral , Proteínas Virais/metabolismo , Antivirais/metabolismo , Mamíferos
6.
Rep Prog Phys ; 85(8)2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35413691

RESUMO

We lay out a comprehensive physics case for a future high-energy muon collider, exploring a range of collision energies (from 1 to 100 TeV) and luminosities. We highlight the advantages of such a collider over proposed alternatives. We show how one can leverage both the point-like nature of the muons themselves as well as the cloud of electroweak radiation that surrounds the beam to blur the dichotomy between energy and precision in the search for new physics. The physics case is buttressed by a range of studies with applications to electroweak symmetry breaking, dark matter, and the naturalness of the weak scale. Furthermore, we make sharp connections with complementary experiments that are probing new physics effects using electric dipole moments, flavor violation, and gravitational waves. An extensive appendix provides cross section predictions as a function of the center-of-mass energy for many canonical simplified models.

7.
Artigo em Chinês | MEDLINE | ID: mdl-34979614

RESUMO

Objective:To evaluate the Eustachian tube function of children with simple adenoid hypertrophy and adenoid hypertrophy with secretory otitis media(OME) by using the A/N value of lateral radiograph of nasopharyngeal X-ray and EDQ-7 scale scores. Methods:Sixty cases of children with adenoid hypertrophy admitted from February 2019 to August 2021 were all underwent nasopharyngeal X-ray lateral radiographs to determine the adenoid/nasopharyngeal cavity ratio(A/N ratio) and then determine the size of adenoids. The Eustachian tube function ETDQ-7 survey was used to evaluate the patient's self-evaluation of the severity of the disease and ear symptoms, and the degree of influence were scored. Subsequently, the correlation between adenoid hypertrophy with OME and ETDQ-7 scores was statistically analyzed by using the Spearman rank correlation statistical method. Results:In adenoid hypertrophy with OME group, the ETDQ-7 scores of A/N≤0.60, A/N 0.61-0.70 and A/N≥0.71 were 4.15±1.75, 14.55±6.67 and 23.95±6.63, respectively. The higher the grade of adenoid hypertrophy, the higher the ETDQ-7 scores. In adenoid hypertrophy with OME group, the degree of adenoid hypertrophy was positively correlated with the ETDQ-7 scores(P<0.05). Conclusion:Adenoid hypertrophy is also one of the potential factors causing OME in children.


Assuntos
Tonsila Faríngea , Tuba Auditiva , Otite Média com Derrame , Tonsila Faríngea/diagnóstico por imagem , Criança , Tuba Auditiva/diagnóstico por imagem , Humanos , Hipertrofia , Fotografação
8.
Pathogens ; 10(9)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34578238

RESUMO

Hepatitis E virus (HEV), a major cause of acute hepatitis worldwide, infects approximately 20 million individuals annually. HEV can infect a wide range of mammalian and avian species, and cause frequent zoonotic spillover, increasingly raising public health concerns. To establish a successful infection, HEV needs to usurp host machineries to accomplish its life cycle from initial attachment to egress. However, relatively little is known about the HEV life cycle, especially the functional role(s) of cellular organelles and their associated proteins at different stages of HEV infection. Here, we summarize current knowledge regarding the relation of HEV with the different cell organelles during HEV infection. Furthermore, we discuss the underlying mechanisms by which HEV infection is precisely regulated in infected cells and the modification of host cell organelles and their associated proteins upon HEV infection.

9.
Dis Markers ; 2021: 9434944, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34257749

RESUMO

The clinical outcome of porcine circovirus 3 (PCV3) infection is still controversial. Herein, a novel PCV3 isolate (PCV3-China/DB-1/2017) with the molecular characterization of 24A and 27K in the Cap protein was used to inoculate three-week-old cesarean-derived, colostrum-deprived piglets. The nine PCV3 DB-1 inoculated piglets exhibited no obvious clinical symptoms or macroscopic lesions. PCV3 displayed a broad histotropism, including the heart, liver, spleen, lung, kidney, brain, lymph nodes, and tonsil, and the lungs and lymph nodes contained a higher quantity of viral genomes compared to that of the other organs. From 7 days after PCV3 DB-1 inoculation, the piglets showed obvious IgG antibody responses against PCV3 rCap-VLPs. The cumulative results demonstrated that PCV3 trend to low pathogenicity.


Assuntos
Infecções por Circoviridae/veterinária , Infecções por Circoviridae/virologia , Circovirus/patogenicidade , Doenças dos Suínos/virologia , Animais , Anticorpos Antivirais/metabolismo , Infecções Assintomáticas , Biomarcadores/metabolismo , China , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/patologia , Circovirus/genética , Circovirus/imunologia , Circovirus/isolamento & purificação , Genoma Viral , Distribuição Aleatória , Sus scrofa , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/patologia , Carga Viral , Proteínas Virais/genética , Proteínas Virais/imunologia
10.
J Biol Chem ; 296: 100435, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33610551

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic represents a global threat, and the interaction between the virus and angiotensin-converting enzyme 2 (ACE2), the primary entry receptor for SARS-CoV-2, is a key determinant of the range of hosts that can be infected by the virus. However, the mechanisms underpinning ACE2-mediated viral entry across species remains unclear. Using infection assay, we evaluated SARS-CoV-2 entry mediated by ACE2 of 11 different animal species. We discovered that ACE2 of Rhinolophus sinicus (Chinese rufous horseshoe bat), Felis catus (domestic cat), Canis lupus familiaris (dog), Sus scrofa (wild pig), Capra hircus (goat), and Manis javanica (Malayan pangolin) facilitated SARS-CoV-2 entry into nonsusceptible cells. Moreover, ACE2 of the pangolin also mediated SARS-CoV-2 entry, adding credence to the hypothesis that SARS-CoV-2 may have originated from pangolins. However, the ACE2 proteins of Rhinolophus ferrumequinum (greater horseshoe bat), Gallus gallus (red junglefowl), Notechis scutatus (mainland tiger snake), or Mus musculus (house mouse) did not facilitate SARS-CoV-2 entry. In addition, a natural isoform of the ACE2 protein of Macaca mulatta (rhesus monkey) with the Y217N mutation was resistant to SARS-CoV-2 infection, highlighting the possible impact of this ACE2 mutation on SARS-CoV-2 studies in rhesus monkeys. We further demonstrated that the Y217 residue of ACE2 is a critical determinant for the ability of ACE2 to mediate SARS-CoV-2 entry. Overall, these results clarify that SARS-CoV-2 can use the ACE2 receptors of multiple animal species and show that tracking the natural reservoirs and intermediate hosts of SARS-CoV-2 is complex.


Assuntos
Enzima de Conversão de Angiotensina 2/genética , COVID-19/epidemiologia , COVID-19/transmissão , Pandemias , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/imunologia , Animais , COVID-19/diagnóstico , COVID-19/imunologia , Gatos , Galinhas/virologia , Quirópteros/virologia , Cães , Elapidae/virologia , Eutérios/virologia , Expressão Gênica , Cabras/virologia , Células HEK293 , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Macaca mulatta/virologia , Camundongos , Modelos Moleculares , Mutação , Ligação Proteica , Estrutura Secundária de Proteína , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Especificidade da Espécie , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Suínos/virologia , Internalização do Vírus
11.
AMB Express ; 10(1): 3, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31912330

RESUMO

PCV3 capsid protein (Cap) is an important antigen for diagnosis and vaccine development. To achieve high-level expression of recombinant PCV3 Cap in Escherichia coli (E. coli), the gene of wild-type entire Cap (wt-eCap) was amplified from clinical samples, and three optimized entire Cap (opti-eCap) and one optimized Cap deleted nuclear location signal (NLS) (opti-dCap) gene fragments encoding the same amino acid sequence with wt-eCap were synthesized based on the codon bias of E. coli. Those gene fragments were inserted into the pET30a expression vector. One recombinant strain with the highest expressed soluble eCap from four entire Cap (one wt-eCap and three opti-eCap) and one recombinant strain expressed opti-dCap were selected for further purification. The purified eCap and dCap were identified by transmission electron microscopy (TEM), a large number of round hollow particles with a diameter of 10 nm virus-like particles (VLPs) were observed in eCap, whereas irregular aggregation of proteins observed in dCap. After formation the VLPs were applied as a coating antigen to establish an indirect ELISA (I-ELISA) for detection of PCV3-specific antibody in swine serum. 373 clinical swine serum samples from China collected in 2019 were tested utilizing the VLP-based I-ELISA method under optimized conditions. To the best of our knowledge, this is the first report of self-assembly into VLPs of PCV3 recombinant Cap. Our results demonstrated that the VLP-based I-ELISA will be a valuable tool for detecting the presence of PCV3 antibodies in serum samples and will facilitate screening of large numbers of swine serum for clinical purposes.

12.
Virus Res ; 265: 20-29, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30831176

RESUMO

Red bone marrow is physiologically unique in that it is both the major hematopoietic organ and a primary lymphoid organ. Porcine reproductive and respiratory syndrome virus (PRRSV) affects normal bone marrow functions. The cumulative effect of PRRSV infection is acute bone marrow failure, i.e., hypoplasia characterized by the absence of normal myeloid and erythroid precursors and increased red bone marrow M:E ratios. The measurable clinical consequence of PRRSV infection on normal red bone marrow functions is a reduction in the number of cells emigrating to the peripheral blood resulting in leucopenia, anemia, and thrombocytopenia. These observations may be explained by the fact that bone marrow-derived mononuclear cells, i.e., imDCs, mDCs, monocytes, macrophages, and myeloid precursor cells are susceptible to PRRSV. Apoptosis in bone marrow-derived cells occurs both as a direct consequence of infection and indirectly via a bystander effect. Immunologically, PRRSV-susceptible mononuclear cells are the first line of defense against microbial infection and responsible for antigen recognition, processing, and presentation to T and B cells; a critical step in the initiation and development of an effective adaptive immune. Thus, impairment of normal immune function renders the host less able to resist and/or eliminate secondary infectious agents and partially explains the synergy between PRRSV and bacterial and viral co-infections.


Assuntos
Células da Medula Óssea/virologia , Medula Óssea/patologia , Medula Óssea/virologia , Síndrome Respiratória e Reprodutiva Suína/patologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Animais , Apresentação de Antígeno , Apoptose , Células da Medula Óssea/patologia , Células Dendríticas/imunologia , Células Dendríticas/virologia , Macrófagos/imunologia , Macrófagos/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Suínos
13.
Med Hypotheses ; 82(6): 781-3, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24735845

RESUMO

Nasal septal perforation, a defect of the nasal mucoperichondrium and cartilage, may induce epistaxis, persistent rhinorrhea and nasal obstruction. Cell-based tissue engineering is a promising therapeutic method for the treatment of nasal septal perforation. However, lack of an adequate source of cells and unsuitable biomaterials greatly hinder the development of cell-based therapy. In this paper, we proposed the application of adipose-derived stem cells combined with decellularized cartilage ECM as a potential graft for the damaged nasal septum, which could help to repair the mucosal and cartilage tissues in the treatment of nasal septal perforation. This new technology could play a novel role in the repair of nasal septal perforation, and in regeneration of damaged nasal cartilage.


Assuntos
Tecido Adiposo/citologia , Células-Tronco Adultas/transplante , Cartilagem/metabolismo , Matriz Extracelular/transplante , Perfuração do Septo Nasal/cirurgia , Matriz Extracelular/metabolismo , Humanos , Modelos Biológicos
14.
Nanotechnology ; 25(14): 145702, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24622377

RESUMO

A new approach for fabrication of a long-term and recoverable antimicrobial nanostructure/textile hybrid without increasing the antimicrobial resistance is demonstrated. Using in situ synthesized Ag nanoparticles (NPs) anchored on ZnO nanowires (NWs) grown on textiles by a 'dip-in and light-irradiation' green chemical method, we obtained ZnONW@AgNP nanocomposites with small-size and uniform Ag NPs, which have shown superior performance for antibacterial applications. These new Ag/ZnO/textile antimicrobial composites can be used for wound dressings and medical textiles for topical and prophylactic antibacterial treatments, point-of-use water treatment to improve the cleanliness of water and antimicrobial air filters to prevent bioaerosols accumulating in ventilation, heating, and air-conditioning systems.


Assuntos
Antibacterianos/química , Anti-Infecciosos/química , Nanopartículas/química , Nanofios/química , Prata/química , Têxteis/microbiologia , Óxido de Zinco/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Humanos , Nanopartículas/microbiologia , Nanopartículas/ultraestrutura , Nanofios/microbiologia , Nanofios/ultraestrutura , Prata/farmacologia , Têxteis/análise , Óxido de Zinco/farmacologia
15.
J Biomed Nanotechnol ; 9(9): 1532-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23980501

RESUMO

Polypyrrole (PPy), as an electrical conductive polymer, has been widely investigated in biomedical fields. In this study, PPy membrane at nanoscale was electrically deposited on indium-tin oxide glass slide with sodium p-toluenesulfonate as supporting electrolyte. Electropolymerization of PPy was performed under a constant 800 mV voltage for 10 seconds. Chemical compositions and morphology were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The results showed that the nanoscaled PPy particles distributed uniformly and the average diameter of PPy particles was 62 nm. Since bone cells can respond to both electrical and mechanical stimulation in vivo, pre-osteoblasts MC3T3-E1 cells were cultured ort nanostructured PPy membrane under the combined electrical and mechanical stimulation. The nano-PPy membrane was conducive to transferring uniform electrical stimulation and applying steady mechanical stimulation. It is suggested that the combined stimulation did not affect cells morphologies significantly. However, cell proliferation tested by MTT, alkaline phosphatase activities, and gene expression of Collagen-I indicated that combined stimulation can enhance the proliferation and differentiation of MC3T3-E1 cells more efficiently than single electrical stimulation or single mechanical stimulation. The combined stimulation through a nano-PPy membrane may provide a highly potential stimulated method in bone tissue engineering.


Assuntos
Mecanotransdução Celular/fisiologia , Membranas Artificiais , Nanoestruturas/química , Osteoblastos/citologia , Osteoblastos/fisiologia , Osteogênese/fisiologia , Polímeros/química , Pirróis/química , Engenharia Tecidual/métodos , Animais , Células 3T3 BALB , Materiais Biocompatíveis/síntese química , Diferenciação Celular/fisiologia , Proliferação de Células , Estimulação Elétrica/métodos , Teste de Materiais , Camundongos , Nanoestruturas/ultraestrutura , Estimulação Física/métodos
16.
Exp Biol Med (Maywood) ; 238(8): 951-9, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23970410

RESUMO

Stem cell therapy may provide a therapeutic method for the replacement and regeneration of damaged neurons of the central nervous system. However, neural stem cells (NSCs) and neural precursor cells (NPCs) are especially vulnerable after transplantation due to a lack of sufficient growth factors at the transplant site. Electrical stimulation (ES) has recently been found to participate in the regulation of cell proliferation, growth, differentiation, and migration, but its underlying anti-apoptotic effects remain unclear. This study investigated the protective effects of biphasic electrical stimulation (BES) on olfactory bulb NPCs against growth factor-deprived apoptosis, examining the survival and apoptotic features of the cells. Differentiation was assessed by neuronal and glial markers. Brain-derived neurotrophic factor-phosphatidylinositol 3'-kinase (BDNF)-PI3K/Akt pathway activation was determined by enzyme-linked immunosorbent assay and Western blot. The chemical inhibitor wortmannin was used to inhibit the PI3K/Akt pathway. BES exerts a protective effect against growth factor-deprived apoptosis in the NPCs. BES enhanced cell survival and decreased the apoptotic/necrotic rate. Expression of phosphorylated Akt and BDNF secretion increased with BES for 12 h. Furthermore, the protective effects of BES were inhibited by blocking PI3K/AKT signalling. These results suggest that BES prevents growth factor-deprived apoptosis through the BDNF-PI3K/Akt signalling. This work strengthens the opinion that BES may be used as an auxiliary strategy for improving cell survival and preventing cell apoptosis in stem cell-based transplantation therapy.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/fisiologia , Terapia por Estimulação Elétrica/métodos , Células-Tronco Neurais/patologia , Bulbo Olfatório/patologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Animais , Apoptose , Diferenciação Celular , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Peptídeos e Proteínas de Sinalização Intercelular/deficiência , Células-Tronco Neurais/fisiologia , Células-Tronco Neurais/ultraestrutura , Bulbo Olfatório/fisiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Transplante de Células-Tronco/métodos
17.
Neurosci Lett ; 487(3): 383-8, 2011 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-21040758

RESUMO

Transplantation of neural stem cells (NSCs) into the cochlea to replace irreversibly damaged sensory epithelia is a potentially valuable remedy for hearing loss. Several mammalian stem cell lines are being successfully transplanted into, or migrated to, the endolymph (EL) fluids environment of the cochlea. However, the survival rate of transplanted cells is relatively low. This study focused on the effect of altering the potassium (K(+)) concentration of artificial EL on cell survival and apoptosis of olfactory bulb neural precursor cells (OB NPCs) in vitro. OB NPCs were prepared and placed in media for 24h, supplemented either with artificial EL, or artificial EL-like solutions of different K(+) concentrations. Survival, apoptotic features and ultrastructural changes in the cells are noted. Artificial EL-like solutions, especially with K(+) concentrations of 50mM or more, resulted in a series of necrotic or apoptotic events. Lower K(+) concentrations (30mM) decreased apoptosis and necrosis, improving the survival rate of cultured NPCs. Thus, it is conceivable that the external K(+) concentration in EL is a key environmental factor to regulate the survival of exogenous stem cells.


Assuntos
Endolinfa/química , Células-Tronco Neurais/ultraestrutura , Potássio/metabolismo , Transplante de Células-Tronco/métodos , Animais , Apoptose/fisiologia , Separação Celular , Sobrevivência Celular , Células-Tronco Embrionárias/metabolismo , Células-Tronco Embrionárias/transplante , Células-Tronco Embrionárias/ultraestrutura , Endolinfa/metabolismo , Citometria de Fluxo , Masculino , Microscopia Eletrônica de Transmissão , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/transplante , Bulbo Olfatório/citologia , Bulbo Olfatório/metabolismo , Ratos , Ratos Sprague-Dawley
18.
Hybridoma (Larchmt) ; 27(3): 187-90, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18582212

RESUMO

The human NOB1 gene is located at chromosome 16q22.1, encoding a protein consisting of one zinc ribbon domain. Here we aimed to efficiently generate a monoclonal antibody against NOB1 protein. We synthesized the peptide APVEHVVADAGAFLRH based on published NOB1 cDNA sequences. The peptide was chemically linked with the carrier protein keyhole limpet hemocyanin and then injected into Balb/c mice. Hybridomas were screened by indirect enzyme-linked immunosorbent assay (ELISA) using either purified 6xHis-NOB1 fusion protein or the peptide. One MAb named H11 (IgG1), effective in detecting the native NOB1 protein, was characterized by ELISA and Western immunoblotting. By using the MAb, we found NOB1 protein was expressed in human lung, liver, spleen, and kidney tissues. Taken together, the MAb H11 would be helpful for understanding the distribution and functions of NOB1.


Assuntos
Anticorpos Monoclonais/química , Técnicas Imunológicas , Proteínas Nucleares/química , Proteínas de Ligação a RNA/química , Animais , Mapeamento Cromossômico , Hemocianinas/química , Hibridomas/metabolismo , Rim/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Modelos Biológicos , Baço/metabolismo , Distribuição Tecidual
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...