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1.
Clin Infect Dis ; 68(9): 1566-1574, 2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-30188973

RESUMO

BACKGROUND: Viral upper respiratory infections (URIs) are common and often precipitate acute otitis media (AOM), caused by bacterial otopathogens, in young children. Acute inflammatory responses initiated in the early phase of viral URI contribute to preventing the development of AOM. Stringently-defined otitis-prone (sOP) children are susceptible to recurrent AOM. METHODS: We assessed proinflammatory cytokine and chemokine levels in the nasopharynxes during viral URIs, and examined the different nasopharyngeal responses between viral URI events and the following AOM episodes in both sOP and non-otitis-prone (NOP) children. RESULTS: The sOP children exhibited significantly more AOM episodes per child (8.86-fold higher), viral URIs (P < .0001), and viral URIs followed by AOMs (P < .0001) than the NOP children. The sOP children had lower nasal proinflammatory levels of interleukin (IL)-6 (P = .05), IL-10 (P = .001), tumor necrosis factor (TNF)-α (P = .004), and regulated on activation, normal T-cell-expressed and -secreted (RANTES; P = .002) than NOP children during viral URIs. NOP children had higher levels of IL-6 (P = .02), IL-10 (P = .02), interferon-γ (P = .003), TNF-α (P = .006), IL-1ß (P = .022), monocyte chemoattractant protein 1 (P = .028), RANTES (P = .005), IL-2 (P = .002), and IL-17 (P = .007) during viral URIs versus AOMs following the URIs, when compared to sOP children. CONCLUSIONS: We conclude that sOP children have more frequent viral URIs than NOP children, due to deficient antiviral nasopharyngeal proinflammatory cytokine and chemokine responses.


Assuntos
Citocinas/imunologia , Inflamação/imunologia , Nasofaringe/microbiologia , Otite Média/microbiologia , Infecções Respiratórias/virologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Otite Média/etiologia , Estudos Prospectivos , Infecções Respiratórias/complicações
2.
Biochem Biophys Res Commun ; 499(4): 882-888, 2018 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-29625108

RESUMO

Mutations in the isocitrate dehydrogenase 1 (IDH1) gene have been identified as one of the earliest events in gliomagenesis, occurring in over 70% of low grade gliomas and are present in the vast majority of secondary glioblastoma (GBM) that develop from these low-grade lesions. The aim of this study was to investigate whether the IDH1 R132H mutation influences the expression of oncogenic miR-20a and shed light on the underlying molecular mechanisms. The findings of the current study demonstrate presence of the IDH1 R132H mutation in primary human glioblastoma cell lines with upregulated HIF-1α expression, downregulating c-MYC activity and resulting in a consequential decrease in miR-20a, which is responsible for cell proliferation and resistance to standard temozolomide treatment. Elucidating the mechanism of oncogenic miR-20a activity introduces its role among well-established signaling pathways (i.e. HIF/c-MYC) and may be a meaningful prognostic biomarker or target for novel therapies among patients with IDH1-mutant glioma.


Assuntos
Regulação para Baixo/genética , Glioma/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isocitrato Desidrogenase/genética , MicroRNAs/genética , Mutação/genética , Oncogenes , Proteínas Proto-Oncogênicas c-myc/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/genética , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/tratamento farmacológico , Glioma/patologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Isocitrato Desidrogenase/metabolismo , MicroRNAs/metabolismo , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-myc/genética , Transdução de Sinais/efeitos dos fármacos , Temozolomida , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
3.
Infect Immun ; 85(2)2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27895132

RESUMO

An increase in Streptococcus pneumoniae nasopharynx (NP) colonization density during a viral coinfection initiates pathogenesis. To mimic natural S. pneumoniae pathogenesis, we commensally colonized the NPs of adult C57BL/6 mice with S. pneumoniae serotype (ST) 6A or 8 and then coinfected them with mouse-adapted H1N1 influenza A virus (PR/8/34). S. pneumoniae established effective commensal colonization, and influenza virus coinfection caused S. pneumoniae NP density to increase, resulting in bacteremia and mortality. We then studied histidine triad protein D (PhtD), an S. pneumoniae adhesin vaccine candidate, for its ability to prevent invasive S. pneumoniae disease in adult and infant mice. In adult mice, the efficacy of PhtD vaccination was compared with that of PCV13. Vaccination with PCV13 led to a greater reduction of S. pneumoniae NP density (>2.5 log units) than PhtD vaccination (∼1-log-unit reduction). However, no significant difference was observed with regard to the prevention of S. pneumoniae bacteremia, and there was no difference in mortality. Depletion of CD4+ T cells in PhtD-vaccinated adult mice, but not PCV13-vaccinated mice, caused a loss of vaccine-induced protection. In infant mice, passive transfer of antisera or CD4+ T cells from PhtD-vaccinated adult mice led to a nonsignificant reduction in NP colonization density, whereas passive transfer of antisera and CD4+ T cells was needed to cause a significant reduction in NP colonization density. For the first time, these data show an outcome with regard to prevention of invasive S. pneumoniae pathogenesis with a protein vaccine similar to that which occurs with a glycoconjugate vaccine despite a less robust reduction in NP bacterial density.


Assuntos
Proteínas de Bactérias/imunologia , Vírus da Influenza A , Influenza Humana , Nasofaringe/imunologia , Nasofaringe/microbiologia , Infecções Pneumocócicas/imunologia , Infecções Pneumocócicas/microbiologia , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Carga Bacteriana , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Portador Sadio , Coinfecção , Modelos Animais de Doenças , Humanos , Ativação Linfocitária/imunologia , Camundongos , Infecções Pneumocócicas/prevenção & controle , Sorogrupo , Streptococcus pneumoniae/classificação
4.
Exp Cell Res ; 343(2): 148-158, 2016 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-27090014

RESUMO

PURPOSE: The aim of this study was to investigate the effect of downregulation of HIF-1α gene on human U251 glioma cells and examine the consequent changes of TMZ induced effects and explore the molecular mechanisms. METHODS: U251 cell line stably expressing HIF-1α shRNA was acquired via lentiviral vector transfection. The mRNA and protein expression alterations of genes involved in our study were determined respectively by qRT-PCR and Western blot. Cell proliferation was measured by MTT assay and colony formation assay, cell invasion/migration capacity was determined by transwell invasion assay/wound healing assay, and cell apoptosis was detected by flow cytometry. RESULTS: We successfully established a U251 cell line with highly efficient HIF-1α knockdown. HIF-1a downregulation sensitized U251 cells to TMZ treatment and enhanced the proliferation-inhibiting, invasion/migration-suppressing, apoptosis-inducing and differentiation-promoting effects exerted by TMZ. The related molecular mechanisms demonstrated that expression of O(6)-methylguanine DNA methyltransferase gene (MGMT) and genes of Notch1 pathway were significantly upregulated by TMZ treatment. However, this upregulation was abrogated by HIF-1α knockdown. We further confirmed important regulatory roles of HIF-1α in the expression of MGMT and activation of Notch1 pathways. CONCLUSION: HIF-1α downregulation sensitizes U251 glioma cells to the temozolomide treatment via inhibiting MGMT expression and Notch1 pathway activation.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Dacarbazina/análogos & derivados , Regulação para Baixo/efeitos dos fármacos , Glioma/tratamento farmacológico , Glioma/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/patologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Invasividade Neoplásica , Proteínas de Neoplasias/metabolismo , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Temozolomida , Transfecção
5.
Cancer Sci ; 107(5): 583-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27171351

RESUMO

Medulloblastoma (MB) is the most common malignant pediatric brain tumor. Despite great improvements in the therapeutic regimen, relapse and leptomeningeal dissemination still pose great challenges to the long-term survival of MB patients. Developing more effective strategies has become extremely urgent. In recent years, a number of malignancies, including MB, have been found to contain a subpopulation of cancer cells known as cancer stem cells (CSCs), or tumor initiating/propagating cells. The CSCs are thought to be largely responsible for tumor initiation, maintenance, dissemination, and relapse; therefore, their pivotal roles have revealed them to be promising targets in MB therapy. Our growing understanding of the major medulloblastoma molecular subgroups and the derivation of some of these groups from specific stem or progenitor cells adds additional layers to the CSC knowledge base. Herein we review the current knowledge of MB stem cells, highlight the molecular mechanisms relating to MB relapse and leptomeningeal dissemination, and incorporate these with the need to develop more effective and accurate therapies for MB patients.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Meduloblastoma/tratamento farmacológico , Meduloblastoma/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Animais , Separação Celular , Humanos , Neoplasias Meníngeas/secundário , Recidiva Local de Neoplasia , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais
6.
Clin Infect Dis ; 59(3): 376-83, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24785236

RESUMO

BACKGROUND: Acute otitis media (AOM) is a leading cause of bacterial pediatric infections associated with viral upper respiratory infections (URIs). We examined the differential impact of respiratory syncytial virus (RSV) and parainfluenza virus URIs on the frequency of AOM caused by Streptococcus pneumoniae (Spn) and nontypeable Haemophilus influenzae (NTHi) in stringently defined otitis-prone (sOP) and non-otitis-prone (NOP) children as a potential mechanism to explain increased susceptibility to AOM. METHODS: Peripheral blood and nasal washes were obtained from sOP and NOP children (n = 309). Colonization events and antiviral responses consisting of total specific immunoglobulin G (IgG) responses, neutralizing antibody responses, and T-cell responses were determined. Isolated neutrophils were infected with varying multiplicities of infection of both viruses, and opsonophagocytosis potential was measured. RESULTS: A significant increase was found in frequency of AOM events caused by Spn and NTHi, with a concurrent RSV infection in sOP children. These results correlated with diminished total RSV-specific IgG, higher viral nasal burdens, and lower IgG neutralizing capacity. The sOP children had diminished T-cell responses to RSV that correlated with lower Toll-like receptor 3/7 transcript and decreased expression of HLA-DR on antigen-presenting cells. RSV interfered with the Spn phagocytic capacity of neutrophils in a dose-dependent manner. Parainfluenza virus infections did not differentially affect AOM events in sOP and NOP children. CONCLUSIONS: Lower innate and adaptive immune responses to RSV in sOP children may slow the kinetics of viral clearance from the nasopharynx and allow for viral interference with antibacterial immune responses, thus contributing to increased frequency of AOMs.


Assuntos
Imunidade Adaptativa , Haemophilus influenzae/isolamento & purificação , Imunidade Inata , Otite Média/imunologia , Paramyxoviridae/isolamento & purificação , Vírus Sinciciais Respiratórios/isolamento & purificação , Streptococcus pneumoniae/isolamento & purificação , Doença Aguda , Pré-Escolar , Feminino , Antígenos HLA-DR/imunologia , Humanos , Lactente , Masculino , Nasofaringe/microbiologia , Otite Média/microbiologia , Estudos Prospectivos , Receptor 3 Toll-Like/imunologia , Receptor 7 Toll-Like/imunologia
7.
Ying Yong Sheng Tai Xue Bao ; 35(3): 622-630, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38646749

RESUMO

Soil nitrogen and phosphorus are two key elements limiting tree growth in subtropical areas. Understanding the regulation of soil microorganisms on nitrogen and phosphorus nutrition is beneficial to reveal maintenance mechanism of soil fertility in plantations. We analyzed the characteristics of soil nitrogen and phosphorus fractions, soil microbial community composition and function, and their relationship across three stands of two-layered Cunninghumia lanceolata + Phoebe bournei with different ages (4, 7 and 11 a) and the pure C. lanceolata plantation. The results showed that the contents of most soil phosphorus fractions increased with increasing two-layered stand age. The increase in active phosphorus fractions with increasing stand age was dominated by the inorganic phosphorus (9.9%-159.0%), while the stable phosphorus was dominated by the organic phosphorus (7.1%-328.4%). The content of soil inorganic and organic nitrogen also increased with increasing two-layered stand age, with NH4+-N and acid hydrolyzed ammonium N contents showing the strongest enhancement, by 152.9% and 80.2%, respectively. With the increase of stand age, the composition and functional groups of bacterial and fungal communities were significantly different, and the relative abundance of some dominant microbial genera (such as Acidothermus, Saitozyma and Mortierella) increased. The relative abundance of phosphorus solubilization and mineralization function genes, nitrogen nitrification function and aerobic ammonia oxidation function genes tended to increase. The functional taxa of fungi explained 48.9% variation of different phosphorus fractions. The conversion of pure plantations to two-layered mixed plantation affected soil phosphorus fractions transformation via changing the functional groups of saprophytes (litter saprophytes and soil saprophytes). Changes in fungal community composition explained 45.0% variation of different nitrogen fractions. Some key genera (e.g., Saitozyma and Mortierella) play a key role in promoting soil nitrogen transformation and accumulation. Therefore, the conversion of pure C. lanceolata plantation to two-layered C. lanceolata + P. bournei plantation was conducive to improving soil nitrogen and phosphorus availability. Bacteria and fungi played important roles in the transformation process of soil nitrogen and phosphorus forms, with greater contribution of soil fungi.


Assuntos
Nitrogênio , Fósforo , Microbiologia do Solo , Solo , Fósforo/análise , Nitrogênio/análise , Nitrogênio/metabolismo , Solo/química , Cunninghamia/crescimento & desenvolvimento , China , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo
8.
Biochemistry ; 52(10): 1802-13, 2013 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-23394681

RESUMO

Mimetics of conformational protein epitopes have broad applications but have been difficult to identify using conventional peptide phage display. The 10th type III domain of human fibronectin (FNfn10) has two extended, randomizable surface-exposed loops and might be more amenable to the identification of such mimetics. We therefore selected a library of FNfn10 clones, randomized in both loops (15 residues in all), for binding to monoclonal antibodies (mAbs) that recognize the HIV-1 envelope glycoprotein. Anti-idiotypic monobodies (αIMs) mimicking both "linear" epitopes (2F5 and 4E10 mAbs) and conformational epitopes (b12 and VRC01 mAbs) were generated. αIMs selected against 2F5 and 4E10 frequently displayed sequence homology to the corresponding linear native epitopes. In the case of b12 and VRC01, we expected that the two constrained loop domains of FNfn10 would both contribute to complex conformational interactions with target antibodies. However, mutagenesis studies revealed differences from this simple model. An αIM selected against b12 was found to bind its cognate antibody via only a few residues within the BC loop of FNfn10, with minimal contribution from the FG loop. Unexpectedly, this was sufficient to generate a protein that engaged its cognate antibody in a manner very similar to that of HIV-1 Env, and with a strong KD (43 nM). In contrast, an αIM selected against VRC01 engaged its cognate antibody in a manner that was dependent on both BC and FG loop sequences. Overall, these data suggest that the FNfn10 scaffold can be used to identify complex structures that mimic conformational protein epitopes.


Assuntos
Anticorpos Anti-Idiotípicos/química , Anticorpos Monoclonais/química , Fibronectinas/química , Sequência de Aminoácidos , Anticorpos Anti-Idiotípicos/genética , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Ligação Competitiva , Materiais Biomiméticos/química , Anticorpos Amplamente Neutralizantes , Fibronectinas/genética , Anticorpos Anti-HIV/sangue , Anticorpos Anti-HIV/química , Anticorpos Anti-HIV/imunologia , HIV-1/química , HIV-1/imunologia , Humanos , Modelos Moleculares , Mutagênese Sítio-Dirigida , Biblioteca de Peptídeos , Conformação Proteica
9.
J Cell Biochem ; 113(6): 1955-65, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22253051

RESUMO

A critical issue in the management of head and neck tumors is radioprotection of the salivary glands. We have investigated whether siRNA-mediated gene knock down of pro-apoptotic mediators can reduce radiation-induced cellular apoptosis in salivary gland cells in vitro. We used novel, pH-responsive nanoparticles to deliver functionally active siRNAs into cultures of salivary gland cells. The nanoparticle molecules are comprised of cationic micelles that electrostatically interact with the siRNA, protecting it from nuclease attack, and also include pH-responsive endosomolytic constituents that promote release of the siRNA into the target cell cytoplasm. Transfection controls with Cy3-tagged siRNA/nanoparticle complexes showed efficiently internalized siRNAs in more than 70% of the submandibular gland cells. We found that introduction of siRNAs specifically targeting the Pkcδ or Bax genes significantly blocked the induction of these pro-apoptotic proteins that normally occurs after radiation in cultured salivary gland cells. Furthermore, the level of cell death from subsequent radiation, as measured by caspase-3, TUNEL, and mitochondrial disruption assays, was significantly decreased. Thus, we have successfully demonstrated that the siRNA/nanoparticle-mediated knock down of pro-apoptotic genes can prevent radiation-induced damage in submandibular gland primary cell cultures.


Assuntos
Apoptose/genética , Nanoconjugados , RNA Interferente Pequeno/farmacologia , Lesões por Radiação/prevenção & controle , Glândulas Salivares/citologia , Glândulas Salivares/efeitos da radiação , Animais , Caspase 3/biossíntese , Neoplasias de Cabeça e Pescoço/radioterapia , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/metabolismo , Cultura Primária de Células , Proteína Quinase C-delta/genética , Proteína Quinase C-delta/metabolismo , Interferência de RNA , Protetores contra Radiação/farmacologia , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
10.
Emerg Infect Dis ; 18(11): 1738-45, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23092680

RESUMO

Antimicrobial treatments and vaccines can alter bacterial interactions in the nasopharynx, thereby altering disease processes. To better understand these interactions, we examined colonization rates of 3 respiratory bacterial pathogens among 320 children when healthy and at onset of acute otitis media (AOM). Bacterial interactions were analyzed with a repeated measures logistic regression model. Among healthy children, Streptococcus pneumoniae and Moraxella catarrhalis were synergistically (positively) associated. Colonization with S. pneumoniae when healthy, but not at onset of AOM, was competitively (negatively) associated with Staphylococcus aureus. Among children with AOM, competitive associations were found between Haemophilus influenzae and S. pneumoniae and between H. influenzae and M. catarrhalis; rates of colonization with H. influenzae were higher. Bacterial interactions result in differing pathogen prevalence during periods of health and at onset of AOM. H. influenzae might become a more common cause of AOM among children who receive pneumococcal conjugate vaccine.


Assuntos
Infecções Bacterianas/microbiologia , Interações Hospedeiro-Patógeno , Nasofaringe/microbiologia , Infecções Bacterianas/epidemiologia , Pré-Escolar , Feminino , Haemophilus influenzae , Humanos , Lactente , Masculino , Moraxella catarrhalis , New York/epidemiologia , Otite Média/epidemiologia , Otite Média/microbiologia , Prevalência , Fatores de Risco , Streptococcus pneumoniae
11.
Cancer Lett ; 482: 126-135, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31954770

RESUMO

Glioblastoma (GBM) has limited therapeutic options. DNA repair mechanisms contribute GBM cells to escape therapies and re-establish tumor growth. Multiple studies have shown that POLD2 plays a critical role in DNA replication, DNA repair and genomic stability. We demonstrate for the first time that POLD2 is highly expressed in human glioma specimens and that expression correlates with poor patient survival. siRNA or shRNA POLD2 inhibited GBM cell proliferation, cell cycle progression, invasiveness, sensitized GBM cells to chemo/radiation-induced cell death and reversed the cytoprotective effects of EGFR signaling. Conversely, forced POLD2 expression was found to induce GBM cell proliferation, colony formation, invasiveness and chemo/radiation resistance. POLD2 expression associated with stem-like cell subsets (CD133+ and SSEA-1+ cells) and positively correlated with Sox2 expression in clinical specimens. Its expression was induced by Sox2 and inhibited by the forced differentiation of GBM neurospheres. shRNA-POLD2 modestly inhibited GBM neurosphere-derived orthotopic xenografts growth, when combined with radiation, dramatically inhibited xenograft growth in a cooperative fashion. These novel findings identify POLD2 as a new potential therapeutic target for enhancing GBM response to current standard of care therapeutics.


Assuntos
Neoplasias Encefálicas/terapia , DNA Polimerase III/genética , DNA Polimerase III/metabolismo , Glioblastoma/terapia , RNA Interferente Pequeno/administração & dosagem , Temozolomida/administração & dosagem , Regulação para Cima , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/efeitos da radiação , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , DNA Polimerase III/antagonistas & inibidores , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/efeitos da radiação , RNA Interferente Pequeno/farmacologia , Radioterapia , Análise de Sobrevida , Temozolomida/uso terapêutico , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/efeitos da radiação , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Emerg Infect Dis ; 15(4): 547-51, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19331730

RESUMO

After our recent discovery of a Streptococcus pneumoniae 19A "superbug" (Legacy strain) that is resistant to all Food and Drug Administration-approved antimicrobial drugs for treatment of acute otitis media (AOM) in children, other S. pneumoniae isolates from children with AOM were characterized by multilocus sequence typing (MLST). Among 40 isolates studied, 16 (40%) were serotype 19A, and 9 (23%) were resistant to multiple antimicrobial drugs. Two others had unreported sequence types (STs) that expressed the 19A capsule, and 8 (88%) of the 9 multidrug-resistant strains were serotype 19A, including the Legacy strain with the new ST-2722. In genetic relatedness, ST-2722 belonged to a cluster of reported strains of S. pneumoniae in which all strains had 6 of the same alleles as ST-156. The multidrug-resistant strains related to ST-156 expressed different capsular serotypes: 9V, 14, 11A, 15C, and 19F.


Assuntos
Doenças Transmissíveis Emergentes/tratamento farmacológico , Doenças Transmissíveis Emergentes/microbiologia , Otite Média/tratamento farmacológico , Otite Média/microbiologia , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/patogenicidade , Sequência de Bases , Criança , Doenças Transmissíveis Emergentes/epidemiologia , Primers do DNA/genética , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla/genética , Genes Bacterianos , Humanos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , New York/epidemiologia , Otite Média/epidemiologia , Filogenia , Infecções Pneumocócicas/epidemiologia , Homologia de Sequência do Ácido Nucleico , Sorotipagem , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/isolamento & purificação
13.
Front Genet ; 10: 1176, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31803245

RESUMO

Acute otitis media (AOM) is the most common pediatric infection for which antibiotics are prescribed in the United States. The role of the respiratory tract microbiome in pathogenesis and immune modulation of AOM remains unexplored. We sought to compare the nasopharyngeal (NP) microbiome of children 1 to 3 weeks prior to onset of AOM vs. at onset of AOM, and the NP microbiome with the microbiome in middle ear (ME). Six children age 6 to 24 months old were studied. Nasal washes (NW) were collected at healthy visits 1 to 3 weeks prior to AOM and at onset of AOM. The middle ear fluids (MEF) were collected by tympanocentesis at onset of AOM. Samples were stored in Trizol reagents or phosphate-buffered saline (PBS) at -80°C until use. The microbiome was characterized by 16S rRNA gene sequencing. Taxonomic designations and relative abundance of bacteria were determined using the RDP classifier tool through QIIME. Cumulative sum scaling normalization was applied before determining bacterial diversity and abundance. Shannon diversity index was calculated in Microsoft excel. The relative abundance of each bacteria species was compared via Mann-Whitney U test. We found that the NW microbiome of children during healthy state or at baseline was more diverse than microbiome during AOM. At AOM, no significant difference in microbiome diversity was found between NW and MEF, although some bacteria species appear to differ in MEF than in NW. The microbiome of samples stored in PBS had significant greater diversity than samples stored in Trizol reagent.

14.
Cancer Commun (Lond) ; 39(1): 81, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796105

RESUMO

BACKGROUND: High-grade glioma (HGG) is a fatal human cancer. Bortezomib, a proteasome inhibitor, has been approved for the treatment of multiple myeloma but its use in glioma awaits further investigation. This study aimed to explore the chemotherapeutic effect and the underlying mechanism of bortezomib on gliomas. METHODS: U251 and U87 cell viability and proliferation were detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, tumor cell spheroid growth, and colony formation assay. Cell apoptosis and cell cycle were detected by flow cytometry. Temozolomide (TMZ)-insensitive cell lines were induced by long-term TMZ treatment, and cells with stem cell characteristics were enriched with stem cell culture medium. The mRNA levels of interested genes were measured via reverse transcription-quantitative polymerase chain reaction, and protein levels were determined via Western blotting/immunofluorescent staining in cell lines and immunohistochemical staining in paraffin-embedded sections. Via inoculating U87 cells subcutaneously, glioma xenograft models in nude mice were established for drug experiments. Patient survival data were analyzed using the Kaplan-Meier method. RESULTS: Bortezomib inhibited the viability and proliferation of U251 and U87 cells in a dose- and time-dependent manner by inducing apoptosis and cell cycle arrest. Bortezomib also significantly inhibited the spheroid growth, colony formation, and stem-like cell proliferation of U251 and U87 cells. When administrated in combination, bortezomib showed synergistic effect with TMZ in vitro and sensitized glioma to TMZ treatment both in vitro and in vivo. Bortezomib reduced both the mRNA and protein levels of Forkhead Box M1 (FOXM1) and its target gene Survivin. The FOXM1-Survivin axis was markedly up-regulated in established TMZ-insensitive glioma cell lines and HGG patients. Expression levels of FOXM1 and Survivin were positively correlated with each other and both related to poor prognosis in glioma patients. CONCLUSIONS: Bortezomib was found to inhibit glioma growth and improved TMZ chemotherapy efficacy, probably via down-regulating the FOXM1-Survivin axis. Bortezomib might be a promising agent for treating malignant glioma, alone or in combination with TMZ.


Assuntos
Antineoplásicos/uso terapêutico , Bortezomib/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Proteína Forkhead Box M1/genética , Glioma/tratamento farmacológico , Survivina/genética , Temozolomida/uso terapêutico , Adolescente , Adulto , Idoso , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Bortezomib/farmacologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Feminino , Proteína Forkhead Box M1/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/genética , Glioma/metabolismo , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Survivina/metabolismo , Temozolomida/farmacologia , Adulto Jovem
15.
J Med Microbiol ; 67(10): 1527-1532, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30136923

RESUMO

PURPOSE: Nontypeable Haemophilus influenzae (NTHi) is a commensal in the human nasopharynx and the cause of pneumonia, meningitis, sinusitis, acute exacerbations of chronic obstructive pulmonary disease and acute otitis media (AOM). AOM is the most common ailment for which antibiotics are prescribed in the United States. With the emergence of new strains of antibiotic-resistant bacteria, finding an effective and broad coverage vaccine to protect against AOM-causing pathogens has become a priority. Mouse models are a cost-effective and efficient way to help determine vaccine efficacy. Here, we describe an NTHi AOM model in C57BL/6J mice, which also utilizes a mouse-adapted H1N1 influenza virus to mimic human coinfection. METHODOLOGY: We tested our coinfection model using a protein vaccine formulation containing protein D, a well-studied NTHi vaccine candidate that can be found in the 10-valent Streptococcus pneumoniae conjugate vaccine. We verified the usefulness of our mouse model by comparing bacterial loads in the nose and ear between protein D-vaccinated and control mice. RESULTS: While there was no measurable difference in nasal bacterial loads, we did detect significant differences in the bacterial loads of ear washes and ear bullae between vaccinated and control mice. CONCLUSION: The results from this study suggest that our NTHi AOM coinfection model is useful for assessing protein vaccines.


Assuntos
Proteínas de Bactérias/imunologia , Proteínas de Transporte/imunologia , Infecções por Haemophilus/prevenção & controle , Vacinas Anti-Haemophilus/imunologia , Haemophilus influenzae/imunologia , Imunoglobulina D/imunologia , Lipoproteínas/imunologia , Otite Média/prevenção & controle , Administração Intranasal , Animais , Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/genética , Proteínas de Transporte/administração & dosagem , Proteínas de Transporte/genética , Coinfecção/microbiologia , Coinfecção/prevenção & controle , Coinfecção/virologia , Modelos Animais de Doenças , Feminino , Infecções por Haemophilus/microbiologia , Vacinas Anti-Haemophilus/administração & dosagem , Vacinas Anti-Haemophilus/genética , Haemophilus influenzae/genética , Haemophilus influenzae/crescimento & desenvolvimento , Humanos , Imunoglobulina D/administração & dosagem , Imunoglobulina D/genética , Vírus da Influenza A Subtipo H1N1/fisiologia , Lipoproteínas/administração & dosagem , Lipoproteínas/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nariz/microbiologia , Nariz/virologia , Otite Média/imunologia , Otite Média/microbiologia , Vacinas Conjugadas/administração & dosagem , Vacinas Conjugadas/imunologia
16.
Oncogene ; 37(38): 5160-5174, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29849122

RESUMO

Mutations in the isocitrate dehydrogenase 1 (IDH1) gene have been identified in a number of cancer types, including brain cancer. The Cancer Genome Atlas project has revealed that IDH1 mutations occur in 70-80% of grade II and grade III gliomas. Until recently, most of the functional studies of IDH1 mutations in cellular models have been conducted in overexpression systems with the IDH1 wild type background. In this study, we employed a modified CRISPR/Cas9 genome editing technique called "single base editing", and efficiently introduced heterozygous IDH1 R132H mutation (IDH1R132H/WT) in human astroglial cells. Global DNA methylation profiling revealed hypermethylation as well as hypomethylation induced by IDH1R132H/WT. Global gene expression analysis identified molecular targets and pathways altered by IDH1R132H/WT, including cell proliferation, extracellular matrix (ECM), and cell migration. Our phenotype analysis indicated that compared with IDH1 wild type cells, IDH1R132H/WT promoted cell migration by upregulating integrin ß4 (ITGB4); and significantly inhibited cell proliferation. Using our mutated IDH1 models generated by "single base editing", we identified novel molecular targets of IDH1R132H/WT, namely Yes-associated protein (YAP) and its downstream signaling pathway Notch, to mediate the cell growth-inhibiting effect of IDH1R132H/WT. In summary, the "single base editing" strategy has successfully created heterozygous IDH1 R132H mutation that recapitulates the naturally occurring IDH1 mutation. Our isogenic cellular systems that differ in a single nucleotide in one allele of the IDH1 gene provide a valuable model for novel discoveries of IDH1R132H/WT-driven biological events.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Astrócitos/citologia , Regulação para Baixo/genética , Heterozigoto , Isocitrato Desidrogenase/genética , Mutação , Fosfoproteínas/metabolismo , Astrócitos/metabolismo , Movimento Celular/genética , Proliferação de Células/genética , Epigênese Genética , Humanos , Fatores de Transcrição , Proteínas de Sinalização YAP
17.
Vaccine ; 35(2): 337-344, 2017 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-27919628

RESUMO

BACKGROUND: Currently licensed serotype-based pneumococcal vaccines are effective in preventing invasive pneumococcal diseases, but less effective in preventing non-bacteremic pneumonia and acute otitis media (AOM). We previously reported that a trivalent pneumococcal protein recombinant vaccine (PPrV) protected against pneumonia in a murine model. Here we evaluated PPrV protection against AOM in an infant murine model. METHODS: C57BL/6J mice were intramuscularly vaccinated at 1-3weeks of age with monovalent pneumococcal histidine triad protein D (PhtD), or pneumococcal choline binding protein A (PcpA), or detoxified pneumolysin (PlyD1), or trivalent vaccine, and transtympanically challenged at 7-8weeks of age with 1×102CFU of pneumococcal strain BG7322 (6A) or 1×104CFU of pneumococcal nontypeable strain 0702064MEF. Serum IgG titers were determined by ELISA. At 24 and 48h post infection (hpi), animals were sacrificed and middle ear fluid (MEF) samples were collected to determine pneumococcal CFUs. RESULTS: We found that vaccination of infant mice with monovalent and trivalent pneumococcal proteins elicited significant serum IgG antibody responses to corresponding component proteins. Vaccination with PhtD reduced BG7322 bacterial burdens in MEF at both 24 (p=0.05) and 48hpi (p=0.16). Vaccination with PcpA significantly reduced the bacterial burdens in MEF at both 24 (p=0.02) and 48hpi (p=0.004), and PlyD1 significantly reduced bacterial burden in MEF at 48hpi (p=0.02). Vaccination with trivalent PPrV (PhtD, PcpA and PlyD1) significantly reduced Spn burdens in MEF at both 24 (p=0.001) and 48hpi (p<0.0001). Similar reductions of bacterial burdens were found when the vaccinated animals were challenged with a non-typeable Spn strain. Vaccinated mice had significantly milder inflammatory cytokine levels (IL-1ß, IL-6, TNF-α, MIP-2 and KC) in middle ears at 24hpi (all p values<0.05). CONCLUSION: Trivalent PPrV confers protection against pneumococcal AOM in an infant murine model.


Assuntos
Otite Média/prevenção & controle , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Animais , Animais Recém-Nascidos , Anticorpos Antibacterianos/sangue , Carga Bacteriana , Proteínas de Bactérias/imunologia , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Orelha Média/microbiologia , Ensaio de Imunoadsorção Enzimática , Exsudatos e Transudatos/microbiologia , Feminino , Imunoglobulina G/sangue , Injeções Intramusculares , Masculino , Camundongos Endogâmicos C57BL , Vacinas Pneumocócicas/administração & dosagem , Resultado do Tratamento , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia
18.
J Infect ; 75(1): 26-34, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28412081

RESUMO

OBJECTIVES: We sought to understand how polymicrobial colonization varies during health, viral upper respiratory infection (URI) and acute upper respiratory bacterial infection to understand differences in infection-prone vs. non-prone patients. METHODS: Nasopharyngeal (NP) samples were collected from 74 acute otitis media (AOM) infection-prone and 754 non-prone children during 2094 healthy visits, 673 viral URI visits and 631 AOM visits. Three otopathogens Streptococcus pneumoniae (Spn), Nontypeable Haemophilus influenzae (NTHi), and Moraxella catarrhalis (Mcat) were identified by culture. RESULTS: NP colonization rates of multiple otopathogens during health were significantly lower than during viral URI, and during URI they were lower than at onset of upper respiratory bacterial infection in both AOM infection-prone and non-prone children. AOM infection-prone children had higher polymicrobial colonization rates than non-prone children during health, viral URI and AOM. Polymicrobial colonization rates of AOM infection-prone children during health were equivalent to that of non-prone children during viral URI, and during viral URI were equivalent to that of non-prone during AOM infection. Spn colonization was positively associated with NTHi and Mcat colonization during health, but negatively during AOM infection. CONCLUSION: The infection-prone patients more frequently have multiple potential bacterial pathogens in the NP than the non-prone patients. Polymicrobial interaction in the NP differs during health and at onset of infection.


Assuntos
Coinfecção/epidemiologia , Coinfecção/microbiologia , Nasofaringe/microbiologia , Infecções Respiratórias/microbiologia , Infecções Respiratórias/virologia , Doença Aguda/epidemiologia , Bactérias/classificação , Bactérias/isolamento & purificação , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/imunologia , Infecções Bacterianas/microbiologia , Pré-Escolar , Coinfecção/imunologia , Suscetibilidade a Doenças/epidemiologia , Suscetibilidade a Doenças/microbiologia , Feminino , Haemophilus influenzae/isolamento & purificação , Haemophilus influenzae/fisiologia , Voluntários Saudáveis , Humanos , Lactente , Estudos Longitudinais , Masculino , Moraxella catarrhalis/isolamento & purificação , Moraxella catarrhalis/fisiologia , Otite Média/microbiologia , Estudos Prospectivos , Infecções Respiratórias/epidemiologia , Streptococcus pneumoniae/isolamento & purificação , Streptococcus pneumoniae/fisiologia
19.
Mol Cell Endocrinol ; 251(1-2): 88-95, 2006 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-16621236

RESUMO

The objective of this study was to identify the transcription factors that regulate the expression of growth hormone receptor (GHR) 1A mRNA, a major GHR mRNA variant in the bovine liver. A deoxyribonuclease I footprint analysis revealed that the GHR1A promoter region -69 to -30 (relative to the transcription start site for GHR1A mRNA) contained binding sites for bovine liver nuclear proteins. Using a yeast one-hybrid analysis, zinc finger binding protein 89 (ZBP-89) was identified as a binding protein to this promoter region. Binding of ZBP-89 to the GHR1A promoter region -69 to -30 was further confirmed by an electrophoretic mobility shift assay. In cotransfection analyses, overexpression of ZBP-89 enhanced (P<0.01) the activity of the GHR1A promoter and this enhancement was dependent on the putative ZBP-89 binding site in the promoter. These results together indicate that ZBP-89 is a transcription factor that regulates the expression of GHR1A mRNA.


Assuntos
Proteínas de Ligação a DNA/genética , Hormônio do Crescimento/metabolismo , Receptores da Somatotropina/genética , Fatores de Transcrição/genética , Dedos de Zinco/genética , Sequência de Aminoácidos , Animais , Bovinos , Pegada de DNA , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Fígado , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro , Receptores da Somatotropina/metabolismo , Análise de Sequência de DNA , Fatores de Transcrição/metabolismo , Transfecção , Dedos de Zinco/fisiologia
20.
Hum Vaccin Immunother ; 12(1): 194-205, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26539741

RESUMO

All currently available Streptococcus pneumoniae (Spn) vaccines have limitations due to their capsular serotype composition. Both the 23-valent Spn polysaccharide vaccine (PPV) and 7, 10, or 13-valent Spn conjugate vaccines (PCV-7, 10, -13) are serotype-based vaccines and therefore they elicit only serotype-specific immunity. Emergence of replacement Spn strains expressing other serotypes has consistently occurred following introduction of capsular serotype based Spn vaccines. Furthermore, capsular polysaccharide vaccines are less effective in protection against non-bacteremic pneumonia and acute otitis media (AOM) than against invasive pneumococcal disease (IPD). These shortcomings of capsular polysaccharide-based Spn vaccines have created high interest in development of non-serotype specific protein-based vaccines that could be effective in preventing both IPD and non-IPD infections. This review discusses the progress to date on development of Spn protein vaccine candidates that are highly conserved by all Spn strains, are highly conserved, exhibit maximal antigenicity and minimal reactogenicity to replace or complement the current capsule-based vaccines. Key to development of a protein based Spn vaccine is an understanding of Spn pathogenesis. Based on pathogenesis, a protein-based Spn vaccine should include one or more ingredients that reduce NP colonization below a pathogenic inoculum. Elimination of all Spn colonization may not be achievable or even advisable. The level of expression of a target protein antigen during pathogenesis is another key to the success of protein based vaccines.. As with virtually all currently licensed vaccines, production of a serum antibody response in response to protein based vaccines is anticipated to provide protection from Spn infections. A significant advantage that protein vaccine formulations can offer over capsule based vaccination is their potential benefits associated with natural priming and boosting to all strains of Spn. One of the most universal and comprehensive approaches of identifying novel vaccine candidates is the investigation of human sera from different disease stages of natural infections. Antigens that are robustly reactive in preliminary human serum screening constitute a pathogen-specific antigenome. This strategy has identified a number of Spn protein vaccine candidates that are moving forward in human clinical trials.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Descoberta de Drogas/tendências , Vacinas Pneumocócicas/imunologia , Vacinas Pneumocócicas/isolamento & purificação , Streptococcus pneumoniae/imunologia , Animais , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Humanos
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