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1.
Environ Res ; 228: 115902, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37059324

RESUMO

In recent years, there has been an increasing focus on the dynamics of material stock, that is, the basis of material flow in the entire ecosystem. With the gradual improvement of the global road network encryption project, the uncontrolled extraction, processing, and transportation of raw materials impose serious resource concerns and environmental pressure. Quantifying material stocks enable governments to formulate scientific policies because socio-economic metabolism, including resource allocation, use, and waste recovery, can be systematically assessed. In this study, OpenStreetMap road network data were used to extract the urban road skeleton, and nighttime light images were divided by watershed to construct regression equations based on geographical location attributes. Resultantly, a generic road material stock estimation model was developed and applied to Kunming. We concluded that (1) the top three stocks are stone chips, macadam, and grit (total weight is 380 million tons), (2) the proportion of asphalt, mineral powder, lime, and fly ash is correspondingly similar, and (3) the unit area stock decreases as the road grade declines; therefore, the branch road has the lowest unit stock.


Assuntos
Cinza de Carvão , Ecossistema , Meios de Transporte
2.
J Nanobiotechnology ; 19(1): 321, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34649589

RESUMO

BACKGROUND: Photothermal therapy (PTT) frequently cause thermal resistance in tumor cells by inducing the heat shock response, limiting its therapeutic effect. Hydrogen sulfide (H2S) with appropriate concentration can reverse the Warburg effect in cancer cells. The combination of PTT with H2S gas therapy is expected to achieve synergistic tumor treatment. METHODS: Here, sulourea (Su) is developed as a thermosensitive/hydrolysable H2S donor to be loaded into Pd nanocubes through in-depth coordination for construction of the Pd-Su nanomedicine for the first time to achieve photo-controlled H2S release, realizing the effective combination of photothermal therapy and H2S gas therapy. RESULTS: The Pd-Su nanomedicine shows a high Su loading capacity (85 mg g-1), a high near-infrared (NIR) photothermal conversion efficiency (69.4%), and NIR-controlled H2S release by the photothermal-triggered hydrolysis of Su. The combination of photothermal heating and H2S produces a strong synergetic effect by H2S-induced inhibition of heat shock response, thereby effectively inhibiting tumor growth. Moreover, high intratumoral accumulation of the Pd-Su nanomedicine after intravenous injection also enables photothermal/photoacoustic dual-mode imaging-guided tumor treatment. CONCLUSIONS: The proposed NIR-responsive heat/H2S release strategy provides a new approach for effective cancer therapy.


Assuntos
Sulfeto de Hidrogênio/química , Nanopartículas Metálicas/química , Nanomedicina/métodos , Paládio/química , Terapia Fototérmica/métodos , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Feminino , Sulfeto de Hidrogênio/uso terapêutico , Raios Infravermelhos , Nanopartículas Metálicas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Paládio/uso terapêutico
3.
Small ; 15(42): e1902926, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31448572

RESUMO

Tumor-microenvironment-responsive theranostics have great potential for precision diagnosis and effective treatment of cancer. Polyaniline (PANI) is the first reported pH-responsive organic photothermal agent and is widely used as a theranostic agent. However, tumor pH-responsive PANI-based theranostic agents are not explored, mainly because the conversion from the emeraldine base (EB) to emeraldine salt (ES) state of PANI requires pH < 4, which is lower than tumor acidic microenvironment. Herein, a tumor pH-responsive PANI-based theranostic agent is designed and prepared for amplified photoacoustic imaging guided augmented photothermal therapy (PTT), through intermolecular acid-base reactions between carboxyl groups of bovine serum albumin (BSA) and imine moieties of PANI. The albumin/PANI assemblies (BSA-PANI) can convert from the EB to ES state at pH < 7, accompanied by the absorbance redshift from visible to near-infrared region. Both in vitro and in vivo results demonstrate that tumor acidic microenvironment can trigger both the photoacoustic imaging (PAI) signal amplification and the PTT efficacy enhancement of BSA-PANI assemblies. This work not only highlights that BSA-PANI assemblies overcome the limitation of low-pH protonation, but also provides a facile assembly strategy for a tumor pH-responsive PANI-based nanoplatform for cancer theranostics.


Assuntos
Compostos de Anilina/química , Hipertermia Induzida , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Técnicas Fotoacústicas , Fototerapia , Soroalbumina Bovina/química , Compostos de Anilina/síntese química , Animais , Materiais Biocompatíveis/química , Bovinos , Feminino , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos BALB C , Soroalbumina Bovina/ultraestrutura
4.
Proc Natl Acad Sci U S A ; 113(51): 14787-14792, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27930307

RESUMO

Inflammatory bowel disease (IBD) results from aberrant immune stimulation against a dysbiotic mucosal but relatively preserved luminal microbiota and preferentially affects males in early onset disease. However, factors contributing to sex-specific risk and the pattern of dysbiosis are largely unexplored. Core 1 ß3GalT-specific molecular chaperone (Cosmc), which encodes an X-linked chaperone important for glycocalyx formation, was recently identified as an IBD risk factor by genome-wide association study. We deleted Cosmc in mouse intestinal epithelial cells (IECs) and found marked reduction of microbiota diversity in progression from the proximal to the distal gut mucosa, but not in the overlying lumen, as seen in IBD. This loss of diversity coincided with local emergence of a proinflammatory pathobiont and distal gut restricted pathology. Mechanistically, we found that Cosmc regulates host genes, bacterial ligands, and nutrient availability to control microbiota biogeography. Loss of one Cosmc allele in males (IEC-Cosmc-/y) resulted in a compromised mucus layer, spontaneous microbe-dependent inflammation, and enhanced experimental colitis; however, females with loss of one allele and mosaic deletion of Cosmc in 50% of crypts (IEC-Cosmc+/-) were protected from spontaneous inflammation and partially protected from experimental colitis, likely due to lateral migration of normal mucin glycocalyx from WT cells over KO crypts. These studies functionally validate Cosmc as an IBD risk factor and implicate it in regulating the spatial pattern of dysbiosis and sex bias in IBD.


Assuntos
Microbioma Gastrointestinal , Genes Ligados ao Cromossomo X , Doenças Inflamatórias Intestinais/genética , Chaperonas Moleculares/genética , Fatores Sexuais , Alelos , Animais , Colite/microbiologia , Feminino , Deleção de Genes , Ligação Genética , Estudo de Associação Genômica Ampla , Glicocálix , Inflamação , Doenças Inflamatórias Intestinais/microbiologia , Mucosa Intestinal/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mosaicismo , Fatores de Risco , Cromossomo X
5.
Transgenic Res ; 27(6): 539-550, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30293127

RESUMO

Agrobacterium-mediated transformation is a complex process that is widely utilized for generating transgenic plants. However, one of the major concerns of this process is the frequent presence of undesirable T-DNA vector backbone sequences in the transgenic plants. To mitigate this deficiency, a ternary strain of A. tumefaciens was modified to increase the precision of T-DNA border nicking such that the backbone transfer is minimized. This particular strain supplemented the native succinamopine VirD1/VirD2 of EHA105 with VirD1/VirD2 derived from an octopine source (pTi15955), the same source as the binary T-DNA borders tested here, residing on a ternary helper plasmid containing an extra copy of the succinamopine VirB/C/G operons and VirD1. Transformation of maize immature embryos was carried out with two different test constructs, pDAB101556 and pDAB111437, bearing the reporter YFP gene and insecticidal toxin Cry1Fa gene, respectively, contained in the VirD-supplemented and regular control ternary strains. Molecular analyses of ~ 700 transgenic events revealed a significant 2.6-fold decrease in events containing vector backbone sequences, from 35.7% with the control to 13.9% with the VirD-supplemented strain for pDAB101556 and from 24.9% with the control to 9.3% with the VirD-supplemented strain for pDAB111437, without compromising transformation efficiency. In addition, while the number of single copy events recovered was similar, there was a 24-26% increase in backbone-free events with the VirD-supplemented strain compared to the control strain. Thus, supplementing existing VirD1/VirD2 genes in Agrobacterium, to recognize diverse T-DNA borders, proved to be a useful tool to increase the number of high quality events in maize.


Assuntos
Agrobacterium tumefaciens/genética , Proteínas de Bactérias/genética , Plantas Geneticamente Modificadas/genética , Fatores de Virulência/genética , Virulência/genética , Zea mays/genética , Agrobacterium tumefaciens/metabolismo , Aminoácidos , Arginina/análogos & derivados , DNA Bacteriano/genética , Plantas Geneticamente Modificadas/microbiologia , Transformação Genética , Zea mays/microbiologia
6.
EMBO J ; 32(23): 3017-28, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24141879

RESUMO

The resident prokaryotic microbiota of the metazoan gut elicits profound effects on the growth and development of the intestine. However, the molecular mechanisms of symbiotic prokaryotic-eukaryotic cross-talk in the gut are largely unknown. It is increasingly recognized that physiologically generated reactive oxygen species (ROS) function as signalling secondary messengers that influence cellular proliferation and differentiation in a variety of biological systems. Here, we report that commensal bacteria, particularly members of the genus Lactobacillus, can stimulate NADPH oxidase 1 (Nox1)-dependent ROS generation and consequent cellular proliferation in intestinal stem cells upon initial ingestion into the murine or Drosophila intestine. Our data identify and highlight a highly conserved mechanism that symbiotic microorganisms utilize in eukaryotic growth and development. Additionally, the work suggests that specific redox-mediated functions may be assigned to specific bacterial taxa and may contribute to the identification of microbes with probiotic potential.


Assuntos
Proliferação de Células , Drosophila/microbiologia , Intestinos/citologia , Larva/citologia , NADH NADPH Oxirredutases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células-Tronco/citologia , Animais , Diferenciação Celular , Drosophila/crescimento & desenvolvimento , Drosophila/metabolismo , Histonas/metabolismo , Interações Hospedeiro-Patógeno , Mucosa Intestinal/metabolismo , Intestinos/microbiologia , Lactobacillus/patogenicidade , Larva/metabolismo , Larva/microbiologia , Camundongos , NADPH Oxidase 1 , Oxirredução , Fosforilação , Transdução de Sinais , Células-Tronco/metabolismo , Células-Tronco/microbiologia , Simbiose
7.
Plant Cell Rep ; 36(4): 519-528, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28160062

RESUMO

KEY MESSAGE: The choice of promoter regulating the selectable marker gene impacts transformation efficiency, copy number and the expression of selectable marker and flanking genes in maize. Viral or plant-derived constitutive promoters are often used to regulate selectable marker genes. We compared two viral promoters, cauliflower mosaic virus (CaMV 35T) and sugarcane bacilliform virus (SCBV) with two plant promoters, rice actin1 (OsAct1) and maize ubiquitin 1 (ZmUbi1) to drive aryloxyalkanoate dioxygenase (aad-1) selectable marker gene in maize inbred line B104. ZmUbi1- and OsAct1-containing constructs demonstrated higher transformation frequencies (43.8 and 41.4%, respectively) than the two viral promoter constructs, CaMV 35T (25%) and SCBV (8%). Interestingly, a higher percentage of single copy events were recovered for SCBV (82.1%) and CaMV 35T (59.3%) promoter constructs, compared to the two plant-derived promoters, OsAct1 (40.0%), and ZmUbi1 (27.6%). Analysis of protein expression suggested that the viral promoter CaMV 35T expressed significantly higher AAD-1 protein (174.6 ng/cm2) than the OsAct1 promoter (12.6 ng/cm2) in T0 leaf tissue. When measured in T2 callus tissue, the two viral promoters both had higher expression and more variability than the two plant-derived promoters. A potential explanation for why viral promoters produce lower transformation efficiencies but higher percentages of low copy number events is discussed. In addition, viral promoters regulating aad-1 were found to influence the expression of upstream flanking genes in both T0 leaf and T2 callus tissue.


Assuntos
Regulação da Expressão Gênica de Plantas/genética , Plantas Geneticamente Modificadas/genética , Regiões Promotoras Genéticas/genética , Transformação Genética/genética , Transgenes/genética , Zea mays/genética , Caulimovirus/genética
8.
Poult Sci ; 95(2): 354-63, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26574031

RESUMO

Salmonella enterica serovar Typhimurium (ST) is a serious infectious disease throughout the world, and a major reservoir for Salmonella is chicken. Chicken infected with Salmonella do not develop clinical disease, this may be the result of important host interactions with key virulence proteins. To study this, we inoculated chicken with mutant Salmonella Typhimurium that lacked the virulence protein AvrA (AvrA(-)). AvrA is referred to as an avirulence factor, as it moderates the host immune response. The lack of the AvrA virulence gene in ST resulted in reduced weight gain, enhanced persistence and greater extraintestinal organ invasion in chickens, as compared to wild-type (WT) ST. Kinome analysis was performed on inoculated cecal tissue. The majority of the signal transduction pathways induced by AvrA(-) and WT ST were similar; however, we observed alterations in innate immune system signaling. In addition, a leukocyte migration pathway was altered by AvrA(-) ST that may allow greater gut barrier permeability and invasion by the mutant. Cytokine expression did not appear significantly altered at 7 d post-inoculation; at 14 d post-inoculation, there was an observed increase in the expression of anti-inflammatory IL-10 in the WT inoculated ceca. This study is the first to describe mutant AvrA(-) ST infection of chicken and provides further insight into the Salmonella responses observed in chicken relative to other species such as humans and cattle.


Assuntos
Proteínas de Bactérias/genética , Galinhas , Doenças das Aves Domésticas/imunologia , Salmonelose Animal/imunologia , Salmonella typhimurium/genética , Salmonella typhimurium/imunologia , Fatores de Virulência/genética , Imunidade Adaptativa , Animais , Proteínas de Bactérias/metabolismo , Ceco/microbiologia , Imunidade Inata , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Transdução de Sinais , Virulência , Fatores de Virulência/metabolismo
9.
J Transl Med ; 13: 215, 2015 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-26143186

RESUMO

BACKGROUND: There are a number of studies regarding to the susceptibility of A20 SNPs in rheumatoid arthritis (RA); however, a few of these studies have shown an association between polymorphisms in the A20 gene and RA risk in the Chinese population. The aim of this study was to investigate the characteristics of A20 gene polymorphisms, the association between polymorphisms and clinical significance in Chinese RA patients. METHODS: PCR and sequencing were used to identify A20 gene polymorphisms in peripheral blood mononuclear cells (PBMCs) (50 cases), synovial fluid (11 cases) from RA patients and PBMCs from 30 healthy individuals. Quantitative Real-time PCR (qRT-PCR) was used to analyze the A20 mRNA expression in 38 RA patients and 40 healthy individuals. Pearson's Chi square test and two independent-samples Wilcoxon tests were used for statistical analysis. RESULTS: Eight single nucleotide polymorphisms (SNPs) (rs5029937, rs3799491, rs598493, rs2307859, rs146534657, rs2230926, rs661561, and rs582757) were identified in PBMCs of RA patients. One new mutation (14284 T > A) was identified in synovial fluid mononuclear cells from one RA case. rs146534657 was identified for the first time in two RA cases. Patients with rs146534657 (12411 A > G, Asn102Ser) AG genotype or rs2230926 (12486 T > G, Phe127Cys) TG genotype had poor outcome. Significantly lower A20 mRNA expression was found in PBMCs from RA patients compared with healthy individuals (p < 0.001). There was a higher A20 mRNA expression in RA patients with rs2230926 TG genotype and rs146534657 AG genotype (11.56 ± 7.39) than patients with rs2230926 TT genotype and rs146534657 AA genotype (5.63 ± 4.37) (p = 0.031). CONCLUSION: Significantly lower A20 expression was found in RA patients. The polymorphisms of A20 were characterized in RA patients. We detected rs146534657 for the first time and identified a new A20 mutation (14284 T > A). A20 rs2230926 TG genotype and rs146534657 AG genotype may be related to poor outcome in RA patients.


Assuntos
Artrite Reumatoide/genética , Proteínas de Ligação a DNA/genética , Predisposição Genética para Doença , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Idoso , Alelos , Sequência de Bases , Estudos de Casos e Controles , Análise Mutacional de DNA , Feminino , Regulação da Expressão Gênica , Frequência do Gene/genética , Loci Gênicos , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Líquido Sinovial/metabolismo , Proteína 3 Induzida por Fator de Necrose Tumoral alfa , Adulto Jovem
10.
Chemistry ; 20(23): 7160-7, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24771671

RESUMO

The development of magnetic nanoparticles (MNPs) with functional groups has been intensively pursued in recent years. Herein, a simple, versatile, and cost-effective strategy to synthesize water-soluble and amino-functionalized MNPs, based on the thermal decomposition of phthalimide-protected metal-organic precursors followed by deprotection, was developed. The resulting amino-functionalized Fe3O4, MnFe2O4, and Mn3O4 MNPs with particle sizes of about 14.3, 7.5, and 6.6 nm, respectively, had narrow size distributions and good dispersibility in water. These MNPs also exhibited high magnetism and relaxivities of r2 = 107.25 mM(-1) s(-1) for Fe3O4, r2 = 245.75 mM(-1) s(-1) for MnFe2O4, and r1 = 2.74 mM(-1) s(-1) for Mn3O4. The amino-functionalized MNPs were further conjugated with a fluorescent dye (rhodamine B) and a targeting ligand (folic acid: FA) and used as multifunctional probes. Magnetic resonance imaging and flow-cytometric studies showed that these probes could specifically target cancer cells overexpressing FA receptors. This new protocol opens a new way for the synthesis and design of water-soluble and amino-functionalized MNPs by an easy and versatile route.


Assuntos
Nanopartículas de Magnetita/química , Metais/química , Ftalimidas/química , Apoptose/efeitos dos fármacos , Compostos Férricos/química , Óxido Ferroso-Férrico/química , Citometria de Fluxo , Corantes Fluorescentes/química , Ácido Fólico/química , Células HeLa , Humanos , Células MCF-7 , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/toxicidade , Compostos de Manganês/química , Óxidos/química , Tamanho da Partícula , Rodaminas/química
11.
Zhonghua Yi Xue Za Zhi ; 94(3): 201-3, 2014 Jan 21.
Artigo em Chinês | MEDLINE | ID: mdl-24731463

RESUMO

OBJECTIVE: To explore the effects of NKp44+NK cells from rheumatoid arthritis (RA) patients on the proliferation and monocyte chemotactic protein 1 production of fibroblast-like synoviocytes (FLS). METHODS: The proportions of natural killer (NK) p44 NK cells in peripheral blood (PB) of 50 RA patients and 50 healthy individuals were detected by flow cytometry. Synovial fluid (SF) samples from 30 RA patients were also detected. NKp44+NK cells in RA SF were sorted by flow cytometry for 5 times. The supernatant level of interleukin (IL)-22 was measured by enzyme-linked immunosorbent assay (ELISA). The proliferation of FLS after an addition of culture supernatant of NKp44+NK cells was detected by methyl thiazolyl tetrazolium (MTT) at 24, 48 and 72 h. Monocyte chemotactic protein (MCP)-1 production of RA FLS after an addition of rhIL-22 was detected by ELISA. RESULTS: The proportion of NKp44+NK cells in PB of RA patients was significantly higher than that of normal controls while the proportion of NKp44+NK cells in SF of RA patients was higher than that in PB of matched RA patients (1.270% vs 0, 15.190% vs 2.425%, P < 0.01). The supernatant level of IL-22 in NKp44+NK cell culture was (1 603 ± 332) ng/L. Rapid proliferation of RA FLS was observed at 24, 48, 72 h after an addition of culture supernatant (P < 0.01). IL-22 antibody obviously inhibited the proliferation of RA FLS induced by NKp44+NK cells. MCP-1 production of RA FLS was detected at 72 h after an addition of rhIL-22 (P < 0.01). CONCLUSION: NKp44+NK cells can promote the proliferation and MCP-1 production of RA FLS through the production of IL-22 so as to play an important role in the synovial proliferation and inflammation of RA.


Assuntos
Artrite Reumatoide/patologia , Células Matadoras Naturais/metabolismo , Adulto , Estudos de Casos e Controles , Proliferação de Células , Células Cultivadas , Quimiocina CCL2/metabolismo , Feminino , Humanos , Interleucinas/metabolismo , Células Matadoras Naturais/citologia , Masculino , Pessoa de Meia-Idade , Receptor 2 Desencadeador da Citotoxicidade Natural/metabolismo , Líquido Sinovial/citologia , Interleucina 22
12.
Biomater Sci ; 12(9): 2341-2355, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38497292

RESUMO

Recently, gas therapy has emerged as a promising alternative treatment for deep-seated tumors. However, some challenges regarding insufficient or uncontrolled gas generation as well as unclear therapeutic mechanisms restrict its further clinical application. Herein, a well-designed nanoreactor based on intracellular glutathione (GSH)-triggered generation of sulfur dioxide (SO2) gas to augment oxidative stress has been developed for synergistic chemodynamic therapy (CDT)/sonodynamic therapy (SDT)/SO2 gas therapy. The nanoreactor (designed as CCM@FH-DNs) is constructed by employing iron-doped hollow mesoporous silica nanoparticles as carriers, the surface of which was modified with the SO2 prodrug 2,4-dinitrobenzenesulfonyl (DNs) and further coated with cancer cell membranes for homologous targeting. The CCM@FH-DNs can not only serve as a Fenton-like agent for CDT, but also as a sonosensitizer for SDT. Importantly, CCM@FH-DNs can release SO2 for SO2-mediated gas therapy. Both in vitro and in vivo evaluations demonstrate that the CCM@FH-DNs nanoreactor performs well in augmenting oxidative stress for SO2 gas therapy-enhanced CDT/SDT via GSH depletion and glutathione peroxidase-4 enzyme deactivation as well as superoxide dismutase inhibition. Moreover, the doped iron ions ensure that the CCM@FH-DNs nanoreactors enable magnetic resonance imaging-guided therapy. Such a GSH-triggered SO2 gas therapy-enhanced CDT/SDT strategy provides an intelligent paradigm for developing efficient tumor microenvironment-responsive treatments.


Assuntos
Glutationa , Estresse Oxidativo , Dióxido de Enxofre , Estresse Oxidativo/efeitos dos fármacos , Glutationa/metabolismo , Glutationa/química , Dióxido de Enxofre/química , Dióxido de Enxofre/farmacologia , Humanos , Animais , Camundongos , Nanopartículas/química , Terapia por Ultrassom , Camundongos Endogâmicos BALB C , Dióxido de Silício/química , Linhagem Celular Tumoral , Feminino
13.
Cell Microbiol ; 14(1): 28-39, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21899703

RESUMO

The enteric pathogen Salmonella typhimurium secretes the preformed AvrA effector protein into host cells. This acetyltransferase has been shown to modulate mammalian intestinal immune and survival responses by inhibition of JNK MAPK. To study the role of this effector in natural enteric infection, we used a mouse model to compare wild-type S. typhimurium to an isogenic AvrA null Salmonella mutant. Salmonella lacking AvrA induced increased intestinal inflammation, more intense systemic cytokine responses, and increased apoptosis in epithelial cells. Increased apoptosis was also observed in extra epithelial macrophages. AvrA null-infected mice consistently showed higher bacterial burden within mucosal lymphoid tissues, spleen and liver by 5 days post infection, which indicated a more severe clinical course. To study the molecular mechanisms involved, recombinant adenoviruses expressing AvrA or mutant AvrA proteins were constructed, which showed appropriate expression and mediated the expected inhibition of JNK signalling. Cultured epithelial cells and macrophages transduced with AvrA expressing adenovirus were protected from apoptosis induced by exogenous stimuli. In conclusion, the results demonstrated that Salmonella AvrA modulates survival of infected macrophages likely via JNK suppression, and prevents macrophage death and rapid bacterial dissemination. AvrA suppression of apoptosis in infected macrophages may allow for establishment of a stable intracellular niche typical of intracellular pathogens.


Assuntos
Apoptose/imunologia , Proteínas de Bactérias/metabolismo , Infecções por Salmonella/imunologia , Salmonella typhimurium/genética , Adenoviridae/genética , Animais , Carga Bacteriana , Proteínas de Bactérias/genética , Linhagem Celular , Citocinas/metabolismo , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Feminino , Mucosa Intestinal/metabolismo , Intestinos/imunologia , Intestinos/microbiologia , Tecido Linfoide/microbiologia , Sistema de Sinalização das MAP Quinases/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Salmonella/metabolismo , Infecções por Salmonella/patologia , Salmonella typhimurium/imunologia , Salmonella typhimurium/metabolismo
14.
Biomater Sci ; 11(5): 1739-1753, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36648208

RESUMO

The efficacy of reactive oxygen species-mediated therapy is generally limited by hypoxia and overexpressed glutathione (GSH) in the tumor microenvironment (TME). To address these issues, herein, a smart Mn3O4/OCN-PpIX@BSA nanoplatform is rationally developed to enhance the combinational therapeutic efficacy of chemodynamic therapy (CDT) and sonodynamic therapy (SDT) through TME modulation. For constructing the catalytic nanoplatform (Mn3O4/OCN-PpIX@BSA), Mn3O4 nanoparticles were grown in situ on oxidized g-C3N4 (OCN) nanosheets, and the as-prepared Mn3O4/OCN nano-hybrids were then successively loaded with protoporphyrin (PpIX) and coated with bovine serum albumin (BSA). The catalase-like Mn3O4 nanoparticles are able to effectively catalyze the overexpressed endogenous H2O2 to produce O2, which could relieve hypoxia and improve the therapeutic effect of combinational CDT/SDT. The decomposition of Mn3O4 by GSH enables the release of Mn2+ ions, which not only facilitates good T1/T2 dual-modal magnetic resonance imaging for tumor localization but also results in the depletion of GSH and the Mn2+-driven Fenton-like reaction, thus further amplifying the oxidative stress and achieving improved therapeutic efficacy. It is worth noting that the Mn3O4/OCN-PpIX@BSA nanocomposites exhibit minimal toxicity to normal tissues at therapeutic doses. These positive findings provide a new strategy for the convenient construction of TME-regulating smart theranostic nanoagents to improve the therapeutic outcomes towards malignant tumors effectively.


Assuntos
Nanopartículas , Neoplasias , Humanos , Microambiente Tumoral , Peróxido de Hidrogênio/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Nanopartículas/uso terapêutico , Oxirredução , Hipóxia , Linhagem Celular Tumoral
15.
ACS Biomater Sci Eng ; 9(2): 797-808, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36662809

RESUMO

Ultrasound (US)-triggered sonodynamic therapy (SDT) has aroused intensive interest as a powerful alternative for cancer treatment in recent years due to its non-invasiveness and deep tissue penetration. However, the therapeutic effect of SDT alone is still limited by intrinsic hypoxia in solid tumors. Combined synergistic therapy strategies are highly desired for improving therapeutic efficiency. Herein, a rationally designed intelligent theranostic nanoplatform is developed for the enhancement of cancer treatment through synergistic SDT and nitric oxide (NO) therapy. This US-triggered nanoplatform is fabricated by integrating a sonosensitizer Rose Bengal (RB) and a NO donor (SNO) into manganese-doped hollow mesoporous silica nanoparticles (MH-SNO@RB). Impressively, the acidic and reducing tumor microenvironment accelerates the sustainable release of Mn ions from the framework, which facilitates the MH-SNO@RB to be used as a contrast agent for magnetic resonance imaging. More importantly, the reactive oxygen species (ROS) generated by RB and NO molecules released from SNO, which are simultaneously triggered by US, can react with each other to yield highly reactive peroxynitrite (ONOO-) ions for effective tumor inhibition both in vitro and in vivo. Furthermore, the nanoplatform demonstrates good hemocompatibility and histocompatibility. This study opens a new strategy for the full utilization of US and intelligent design avenues for high-performance cancer treatment.


Assuntos
Nanopartículas , Terapia por Ultrassom , Óxido Nítrico , Linhagem Celular Tumoral , Terapia por Ultrassom/métodos , Nanopartículas/uso terapêutico , Espécies Reativas de Oxigênio
16.
Gene ; 887: 147745, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37640117

RESUMO

Fertilization of the egg by the sperm is the first vital stage of embryogenesis. In mammals, only one sperm is incorporated into the oocyte. Polyspermy is a key anomaly of fertilization that is generally lethal to the embryo. To date, only a few causative genes for polyspermy have been reported. In a recent study, a homozygous variant in astacin-like metalloendopeptidase (ASTL), which encodes the ovastacin enzyme that cleaves ZP2 to prevent polyspermy, was found to be associated with female infertility characterized by polyspermy in vitro. Herein, we identified two ASTL variants in a Chinese woman likely responsible for her primary infertility and polyspermy in in vitro fertilization. Both variants were located within the key catalytic domain and predicted to alter hydrogen bonds, potentially impairing protein stability. Moreover, expression and immunoblot analyses in CHO-K1 cells indicated abnormal ovastacin zymogen activation or decreased enzyme stability. Intracytoplasmic sperm injection treatment successfully bypassed the defect in polyspermy blocking and resulted in a live birth. Our study associates ASTL variants with human infertility and further supports the contribution of this gene to blocking polyspermy in humans. Our findings expand the spectrum of ASTL mutations and should facilitate the diagnosis of oocyte-borne polyspermy.


Assuntos
Infertilidade Feminina , Feminino , Humanos , Masculino , Gravidez , Fertilização in vitro , Infertilidade Feminina/genética , Infertilidade Feminina/terapia , Nascido Vivo , Metaloproteases , Sêmen , Injeções de Esperma Intracitoplásmicas
17.
Nanoscale ; 15(22): 9652-9662, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37204249

RESUMO

The ingenious combination of nano-enzymes with multi-enzyme activities and therapeutic drugs that can promote reactive oxygen species (ROS) production in cancer cells will enhance the therapeutic efficacy of nanomedicines on malignant tumors by amplifying oxidative stress. Herein, PEGylated Ce-doped hollow mesoporous silica nanoparticles (Ce-HMSN-PEG) loaded with saikosaponin A (SSA) are elaborately constructed as a smart nanoplatform for improving the efficiency of tumor therapy. The carrier Ce-HMSN-PEG showed multi-enzyme activities due to the presence of mixed Ce3+/Ce4+ ions. In the tumor microenvironment, peroxidase-like Ce3+ ions convert endogenous H2O2 into highly toxic ˙OH for chemodynamic therapy, while Ce4+ ions not only show catalase-like activity to reduce tumor hypoxia but also exhibit glutathione (GSH) peroxidase-mimicking properties to effectively deplete GSH in tumor cells. Moreover, the loaded SSA can cause the enrichment of superoxide anions (˙O2-) and H2O2 within tumor cells by disrupting mitochondrial functions. By integrating the respective advantages of Ce-HMSN-PEG and SSA, the as-prepared SSA@Ce-HMSN-PEG nanoplatform can efficiently trigger cancer cell death and inhibit tumor growth via significantly enhanced ROS production. Therefore, this positive combination therapy strategy has a good application prospect for enhancing antitumor efficacy.


Assuntos
Neuropatia Hereditária Motora e Sensorial , Neoplasias , Humanos , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Superóxidos , Peroxidases , Glutationa , Linhagem Celular Tumoral , Microambiente Tumoral , Neoplasias/tratamento farmacológico
18.
iScience ; 26(6): 106979, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37378327

RESUMO

In this study, we evaluated the effect of a specific synbiotic on CAC (AOM/DSS-induced colitis-associated cancer). We confirmed that the synbiotic intervention was able to protect the intestinal barrier and inhibit CAC occurrence via upregulating tight junction proteins and anti-inflammatory cytokines, and downregulating pro-inflammatory cytokines. Moreover, the synbiotic significantly improved the disorder of the colonic microbiota of CAC mice, promoted the formation of SCFAs and the production of secondary bile acids, and alleviated the accumulation of primary bile acids in the CAC mice. Meanwhile, the synbiotic could significantly inhibit the abnormal activation of the intestinal Wnt/ß-catenin signaling pathway significantly related to IL-23. In a word, the synbiotic can inhibit the occurrence and development of colorectal tumors and it may be a functional food to prevent inflammation-related colon tumors, and the research also provided a theoretical basis for improving the intestinal microecological environment through diet therapy.

19.
Gene ; 866: 147350, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-36898512

RESUMO

Cell division cycle associated 8 (CDCA8) is a component of the chromosomal passenger complex and plays an essential role in mitosis, meiosis, cancer growth, and undifferentiated state of embryonic stem cells. However, its expression and role in adult tissues remain largely uncharacterized. Here, we studied the CDCA8 transcription in adult tissues by generating a transgenic mouse model, in which the luciferase was driven by a 1-kb human CDCA8 promoter. Our previous study showed that this 1-kb promoter was active enough to dictate reporter expression faithfully reflecting endogenous CDCA8 expression. Two founder mice carrying the transgene were identified. In vivo imaging and luciferase assays in tissue lysates revealed that CDCA8 promoter was highly activated and drove robust luciferase expression in testes. Subsequently, immunohistochemical and immunofluorescent staining showed that in adult transgenic testes, the expression of luciferase was restricted to a subset of spermatogonia that were located along the basement membrane and positive for the expression of GFRA1, a consensus marker for early undifferentiated spermatogonia. These findings for the first time indicate that the CDCA8 was transcriptionally activated in testis and thus may play a role in adult spermatogenesis. Moreover, the 1-kb CDCA8 promoter could be used for spermatogonia-specific gene expression in vivo and the transgenic lines constructed here could also be used for recovery of spermatogonia from adult testes.


Assuntos
Espermatogônias , Testículo , Masculino , Humanos , Adulto , Camundongos , Animais , Testículo/metabolismo , Espermatogônias/metabolismo , Espermatogênese/genética , Camundongos Transgênicos , Luciferases/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo
20.
Front Microbiol ; 14: 1219214, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37608952

RESUMO

Introduction: Swab pooling may allow for more efficient use of point-of-care assays for SARS-CoV-2 detection in settings where widespread testing is warranted, but the effects of pooling on assay performance are not well described. Methods: We tested the Thermo-Fisher Accula rapid point-of-care RT-PCR platform with contrived pooled nasal swab specimens. Results: We observed a higher limit of detection of 3,750 copies/swab in pooled specimens compared to 2,250 copies/swab in individual specimens. Assay performance appeared worse in a specimen with visible nasal mucous and debris, although performance was improved when using a standard laboratory mechanical pipette compared to the transfer pipette included in the assay kit. Conclusion: Clinicians and public health officials overseeing mass testing efforts must understand limitations and benefits of swab or sample pooling, including reduced assay performance from pooled specimens. We conclude that the Accula RT-PCR platform remains an attractive candidate assay for pooling strategies owing to the superior analytical sensitivity compared to most home use and point-of-care tests despite the inhibitory effects of pooled specimens we characterized.

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