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1.
Nature ; 613(7944): 485-489, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36653565

RESUMO

Antiferromagnetic spintronics1-16 is a rapidly growing field in condensed-matter physics and information technology with potential applications for high-density and ultrafast information devices. However, the practical application of these devices has been largely limited by small electrical outputs at room temperature. Here we describe a room-temperature exchange-bias effect between a collinear antiferromagnet, MnPt, and a non-collinear antiferromagnet, Mn3Pt, which together are similar to a ferromagnet-antiferromagnet exchange-bias system. We use this exotic effect to build all-antiferromagnetic tunnel junctions with large nonvolatile room-temperature magnetoresistance values that reach a maximum of about 100%. Atomistic spin dynamics simulations reveal that uncompensated localized spins at the interface of MnPt produce the exchange bias. First-principles calculations indicate that the remarkable tunnelling magnetoresistance originates from the spin polarization of Mn3Pt in the momentum space. All-antiferromagnetic tunnel junction devices, with nearly vanishing stray fields and strongly enhanced spin dynamics up to the terahertz level, could be important for next-generation highly integrated and ultrafast memory devices7,9,16.

2.
Int Immunol ; 36(4): 143-154, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38180817

RESUMO

Innate immunity plays an important role in host defense against microbial infections. It also participates in activation of acquired immunity through cytokine production and antigen presentation. Pattern recognition receptors such as Toll-like receptors and nucleotide oligomerization domain-like receptors sense invading pathogens and associated tissue injury, after which inflammatory mediators such as pro-inflammatory cytokines and nitric oxide are induced. Supersulfides are molecular species possessing catenated sulfur atoms such as persulfide and polysulfide moieties. They have recently been recognized as important regulators in cellular redox homeostasis by acting as potent antioxidants and nucleophiles. In addition, recent studies suggested that supersulfides are critically involved in the regulation of innate immune and inflammatory responses. In this review, we summarize current knowledge of the chemistry and biology of supersulfides, with particular attention to their roles in regulation of innate immune, and inflammatory responses. Studies with animal models of infection and inflammation demonstrated the potent anti-inflammatory functions of supersulfides such as blocking pro-inflammatory signaling cascades, reducing oxidative stresses, and inhibiting replication of microbial pathogens including severe acute respiratory syndrome coronavirus 2. Precise understanding of how supersulfides regulate innate immune responses is the necessary requirement for developing supersulfide-based diagnostic as well as therapeutic strategies against inflammatory disorders.


Assuntos
Imunidade Adaptativa , Imunidade Inata , Animais , Transdução de Sinais , Citocinas , Receptores Toll-Like
3.
Int Immunol ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899915

RESUMO

Interferons (IFNs) are cytokines produced and secreted by immune cells when viruses, tumor cells, and so forth, invade the body. Their biological effects are diverse, including antiviral, cell growth-inhibiting, and antitumor effects. The main subclasses of interferons include type-I (e.g., IFN-α and IFN-ß) and type-II (IFN-γ), which activate intracellular signals by binding to type-I and type-II IFN receptors, respectively. We have previously shown that when macrophages are treated with supersulfide donors, which have polysulfide structures in which three or more sulfur atoms are linked within the molecules, IFN-ß-induced cellular responses, including signal transducer and activator of transcription 1 (STAT1) phosphorylation and inducible nitric oxide synthase (iNOS) expression, were strongly suppressed. However, the subfamily specificity of the suppression of IFN signals by supersulfides and the mechanism of this suppression are unknown. This study demonstrated that supersulfide donor N-acetyl-L-cysteine tetrasulfide (NAC-S2) can inhibit IFN signaling in macrophages stimulated not only with IFN-α/ß but also with IFN-γ. Our data suggest that NAC-S2 blocks phosphorylation of Janus kinases (JAKs), thereby contributes to the inhibition of phosphorylation of STAT1. Under the current experimental conditions, hydrogen sulfide (H2S) donor NaHS failed to inhibit IFN signaling. Similar to NAC-S2, carbohydrate-based supersulfide donor thioglucose tetrasulfide (TGS4) was capable of strongly inhibiting tumor necrosis factor-αproduction, iNOS expression, and nitric oxide production from macrophages stimulated with lipopolysaccharide. Further understanding of molecular mechanisms how supersulfide donors exhibit their inhibitory actions towards JAK/STAT signaling is necessary basis for development of supersulfide-based therapeutic strategy against autoimmune disorders with dysregulated IFN signaling.

4.
Glob Chang Biol ; 30(2): e17177, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38348630

RESUMO

Maintaining or even increasing crop yields while reducing nitrous oxide (N2 O) emissions is necessary to reconcile food security and climate change, while the metric of yield-scaled N2 O emission (i.e., N2 O emissions per unit of crop yield) is at present poorly understood. Here we conducted a global meta-analysis with more than 6000 observations to explore the variation patterns and controlling factors of yield-scaled N2 O emissions for maize, wheat and rice and associated potential mitigation options. Our results showed that the average yield-scaled N2 O emissions across all available data followed the order wheat (322 g N Mg-1 , with the 95% confidence interval [CI]: 301-346) > maize (211 g N Mg-1 , CI: 198-225) > rice (153 g N Mg-1 , CI: 144-163). Yield-scaled N2 O emissions for individual crops were generally higher in tropical or subtropical zones than in temperate zones, and also showed a trend towards lower intensities from low to high latitudes. This global variation was better explained by climatic and edaphic factors than by N fertilizer management, while their combined effect predicted more than 70% of the variance. Furthermore, our analysis showed a significant decrease in yield-scaled N2 O emissions with increasing N use efficiency or in N2 O emissions for production systems with cereal yields >10 Mg ha-1 (maize), 6.6 Mg ha-1 (wheat) or 6.8 Mg ha-1 (rice), respectively. This highlights that N use efficiency indicators can be used as valuable proxies for reconciling trade-offs between crop production and N2 O mitigation. For all three major staple crops, reducing N fertilization by up to 30%, optimizing the timing and placement of fertilizer application or using enhanced-efficiency N fertilizers significantly reduced yield-scaled N2 O emissions at similar or even higher cereal yields. Our data-driven assessment provides some key guidance for developing effective and targeted mitigation and adaptation strategies for the sustainable intensification of cereal production.


Assuntos
Agricultura , Oryza , Agricultura/métodos , Triticum , Zea mays , Fertilizantes , Óxido Nitroso/análise , Produtos Agrícolas , Grão Comestível/química , Solo
5.
Biol Pharm Bull ; 46(11): 1535-1547, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37914356

RESUMO

The introduction of combined anti-retroviral therapy (cART) in 1996, along with a continual breakthrough in anti-human immunodeficiency virus-1 (HIV-1) drugs, has improved the life expectancies of HIV-1-infected individuals. However, the incidence of drug-resistant viruses between individuals undergoing cART and treatment-naïve individuals is a common challenge. Therefore, there is a requirement to explore potential drug targets by considering various stages of the viral life cycle. For instance, the late stage, or viral release stage, remains uninvestigated extensively in antiviral drug discovery. In this study, we prepared a natural plant library and selected candidate plant extracts that inhibited HIV-1 release based on our laboratory-established screening system. The plant extracts from Epilobium hirsutum L. and Chamerion angustifolium (L.) Holub, belonging to the family Onagraceae, decreased HIV-1 release and accelerated the apoptosis in HIV-1-infected T cells but not uninfected T cells. A flavonol glycoside quercetin with oenothein B in Onagraceae reduced HIV-1 release in HIV-1-infected T cells. Moreover, extracts from Chamerion angustifolium (L.) Holub and Senna alexandrina Mill. inhibited the infectivity of progeny viruses. Together, these results suggest that C. angustifolium (L.) Holub contains quercetin with oenothein B that synergistically blocks viral replication and kills infected cells via an apoptotic pathway. Consequently, the plant extracts from the plant library of Turkey might be suitable candidates for developing novel anti-retroviral drugs that target the late phase of the HIV-1 life cycle.


Assuntos
HIV-1 , Onagraceae , Humanos , Quercetina/farmacologia , Extratos Vegetais/farmacologia , Turquia , Apoptose
6.
PLoS Genet ; 16(2): e1008641, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32059012

RESUMO

Men of predominantly African Ancestry (AA) have higher prostate cancer (CaP) incidence and worse survival than men of predominantly European Ancestry (EA). While socioeconomic factors drive this disparity, genomic factors may also contribute to differences in the incidence and mortality rates. To compare the prevalence of prostate tumor genomic alterations and transcriptomic profiles by patient genetic ancestry, we evaluated genomic profiles from The Cancer Genome Atlas (TCGA) CaP cohort (n = 498). Patient global and local genetic ancestry were estimated by computational algorithms using genotyping data; 414 (83.1%) were EA, 61 (12.2%) were AA, 11 (2.2%) were East Asian Ancestry (EAA), 10 (2.0%) were Native American (NA), and 2 (0.4%) were other ancestry. Genetic ancestry was highly concordant with self-identified race/ethnicity. Subsequent analyses were limited to 61 AA and 414 EA cases. Significant differences were observed by ancestry in the frequency of SPOP mutations (20.3% AA vs. 10.0% EA; p = 5.6×10-03), TMPRSS2-ERG fusions (29.3% AA vs. 39.6% EA; p = 4.4×10-02), and PTEN deletions/losses (11.5% AA vs. 30.2% EA; p = 3.5×10-03). Differentially expressed genes (DEGs) between AAs and EAs showed significant enrichment for prostate eQTL target genes (p = 8.09×10-48). Enrichment of highly expressed DEGs for immune-related pathways was observed in AAs, and for PTEN/PI3K signaling in EAs. Nearly one-third of DEGs (31.3%) were long non-coding RNAs (DE-lncRNAs). The proportion of DE-lncRNAs with higher expression in AAs greatly exceeded that with lower expression in AAs (p = 1.2×10-125). Both ChIP-seq and RNA-seq data suggested a stronger regulatory role for AR signaling pathways in DE-lncRNAs vs. non-DE-lncRNAs. CaP-related oncogenic lncRNAs, such as PVT1, PCAT1 and PCAT10/CTBP1-AS, were found to be more highly expressed in AAs. We report substantial heterogeneity in the prostate tumor genome and transcriptome between EA and AA. These differences may be biological contributors to racial disparities in CaP incidence and outcomes.


Assuntos
Biomarcadores Tumorais/genética , Negro ou Afro-Americano/genética , Disparidades nos Níveis de Saúde , Neoplasias da Próstata/genética , População Branca/genética , Biomarcadores Tumorais/metabolismo , Sequenciamento de Cromatina por Imunoprecipitação , Estudos de Coortes , Regulação Neoplásica da Expressão Gênica , Genoma Humano/genética , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Nucleares/genética , Proteínas de Fusão Oncogênica/genética , PTEN Fosfo-Hidrolase/genética , Neoplasias da Próstata/epidemiologia , RNA Longo não Codificante/metabolismo , RNA-Seq , Receptores Androgênicos/genética , Proteínas Repressoras/genética , Transcriptoma/genética
7.
Clin Exp Hypertens ; 44(6): 507-513, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35621164

RESUMO

OBJECTIVE: The lack of a well-established animal model limits the clarification of the detailed mechanisms of the pathogenesis of systemic sclerosis with pulmonary hypertension (SSc-PH) and the development of effective treatments for it. METHODS: In this study, New Zealand rabbits were injected with monocrotaline (MCT), bleomycin (BLM), and MCT plus BLM, respectively. Three and six weeks after the first injection, the mean pulmonary artery pressure (mPAP) was measured. Skin and lung samples were isolated and the histological changes were analyzed by hematoxylin and eosin staining or Masson's trichrome staining. RESULTS: All groups of rabbits showed an increased mean mPAP compared with the saline-injected rabbits. The high mPAP persisted until week six only in the MCT and MCT + BLM groups. Furthermore, persistent high Fulton's indices were found in the MCT and MCT + BLM groups, indicating that these treatments successfully induced right ventricular hypertrophy. The rabbits in the MCT + BLM group developed severe lung inflammation, as evidenced by a high level of neutrophil infiltration in the pulmonary interstitium. Importantly, pathological changes of the skin in the MCT + BLM group were observed, and further damage to the skin was caused by additional exposure to MCT plus BLM. Meanwhile, an excessive production of cytokines, including tumor necrosis factor alpha (TNF-α), and transforming growth factor beta 1 (TGF-ß1), were detected in the MCT + BLM group. CONCLUSION: These data indicate that SSc-PH induced by co-injection with MCT plus BLM shows persistent fibrosis and progressive PH, constituting a potential study model for SSc-PH.


Assuntos
Hipertensão Pulmonar , Escleroderma Sistêmico , Animais , Bleomicina/metabolismo , Bleomicina/toxicidade , Hipertensão Pulmonar/induzido quimicamente , Pulmão/metabolismo , Monocrotalina/toxicidade , Coelhos , Escleroderma Sistêmico/induzido quimicamente , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/metabolismo
8.
Int J Mol Sci ; 23(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35806223

RESUMO

Salmonella Typhimurium is an invasive enteric pathogen that causes gastroenteritis in humans and life-threatening systemic infections in mice. During infection of the intestine, S. Typhimurium can exploit nitrate as an electron acceptor to enhance its growth. However, the roles of nitrate on S. Typhimurium systemic infection are unknown. In this study, nitrate levels were found to be significantly increased in the liver and spleen of mice systemically infected by S. Typhimurium. Mutations in genes encoding nitrate transmembrane transporter (narK) or nitrate-producing flavohemoprotein (hmpA) decreased the replication of S. Typhimurium in macrophages and reduced systemic infection in vivo, suggesting that nitrate utilization promotes S. Typhimurium systemic virulence. Moreover, nitrate utilization contributes to the acidification of the S. Typhimurium cytoplasm, which can sustain the virulence of S. Typhimurium by increasing the transcription of virulence genes encoding on Salmonella pathogenicity island 2 (SPI-2). Furthermore, the growth advantage of S. Typhimurium conferred by nitrate utilization occurred only under low-oxygen conditions, and the nitrate utilization was activated by both the global regulator Fnr and the nitrate-sensing two-component system NarX-NarL. Collectively, this study revealed a novel mechanism adopted by Salmonella to interact with its host and increase its virulence.


Assuntos
Salmonelose Animal , Salmonella typhimurium , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Camundongos , Nitratos , Virulência/genética
9.
Br J Cancer ; 124(5): 963-974, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33299132

RESUMO

BACKGROUND: Fusobacterium nucleatum (F. nucleatum) is a gut microbe implicated in gastrointestinal tumorigenesis. Predicting the chemotherapeutic response is critical to developing personalised therapeutic strategies for oesophageal cancer patients. The present study investigated the relationship between F. nucleatum and chemotherapeutic resistance in oesophageal squamous cell carcinoma (ESCC). METHODS: We examined the relationship between F. nucleatum and chemotherapy response in 120 ESCC resected specimens and 30 pre-treatment biopsy specimens. In vitro studies using ESCC cell lines and co-culture assays further uncovered the mechanism underlying chemotherapeutic resistance. RESULTS: ESCC patients with F. nucleatum infection displayed lesser chemotherapeutic response. The infiltration and subsistence of F. nucleatum in the ESCC cells were observed by transmission electron microscopy and laser scanning confocal microscopy. We also observed that F. nucleatum modulates the endogenous LC3 and ATG7 expression, as well as autophagosome formation to induce chemoresistance against 5-FU, CDDP, and Docetaxel. ATG7 knockdown resulted in reversal of F. nucleatum-induced chemoresistance. In addition, immunohistochemical studies confirmed the correlation between F. nucleatum infection and ATG7 expression in 284 ESCC specimens. CONCLUSIONS: F. nucleatum confers chemoresistance to ESCC cells by modulating autophagy. These findings suggest that targeting F. nucleatum, during chemotherapy, could result in variable therapeutic outcomes for ESCC patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Autofagia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Infecções por Fusobacterium/complicações , Fusobacterium nucleatum/patogenicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/microbiologia , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/microbiologia , Feminino , Seguimentos , Infecções por Fusobacterium/microbiologia , Humanos , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
10.
Microbiol Immunol ; 65(10): 449-461, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34251710

RESUMO

Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen that presents a serious risk to immunosuppressed individuals and other extremely vulnerable patients such as those in intensive care units. The emergence of multidrug-resistant Pseudomonas strains has increased the need for new antipseudomonal agents. In this study, a series of amino group-modified aminopenicillin derivatives was synthesized that have different numbers of carboxyl groups and structurally resemble carboxypenicillin-ureidopenicillin hybrids, and their antipseudomonal activities were evaluated. Among the derivatives synthesized, diethylenetriaminepentaacetic acid (DTPA)-modified amoxicillin (DTPA-Amox) showed potent antipseudomonal activity, not only against the laboratory strain PAO1 but also against clinically isolated Pseudomonas strains that were resistant to piperacillin and carbenicillin. DTPA-Amox had no obvious cytotoxic effects on cultured mammalian cells. In addition, in an in vivo model of leukopenia, DTPA-Amox treatment produced a moderate but statistically significant improvement in the survival of mice with P. aeruginosa strain PAO1 infection. These data suggest that polycarboxylation by DTPA conjugation is an effective approach to enhance antipseudomonal activity of aminopenicillins.


Assuntos
Infecções por Pseudomonas , beta-Lactamas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Penicilinas , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa , beta-Lactamas/farmacologia
11.
J Clin Biochem Nutr ; 68(1): 5-8, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33536706

RESUMO

Cysteine persulfide (CysSSH) and polysulfides (CysS[S] n H, n>1) are cysteine derivatives having sulfane sulfur atoms bound to cysteine thiol. Recent advances in the development of analytical methods for detection and quantification of persulfides and polysulfides have revealed the biological presence, in both prokaryotes and eukaryotes, of persulfide/polysulfide in diverse forms such as CysSSH, glutathione persulfide and protein persulfides. Accumulating evidence has suggested that persulfide/polysulfide species may involve in a variety of biological events such as biosyntheses of sulfur-containing molecules, tRNA modification, regulation of redox-dependent signal transduction, mitochondrial energy metabolism via sulfur respiration, cytoprotection from oxidative stress via their antioxidant activities, and anti-inflammation against Toll-like receptor-mediated inflammatory responses. Development of chemical sulfur donors may facilitate further understanding of physiological and pathophysiological roles of persulfide/polysulfide species, including regulatory roles of these species in immune responses.

12.
Biochem Biophys Res Commun ; 525(4): 1068-1073, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32184018

RESUMO

Subtilase cytotoxin (SubAB) is a member of bacterial AB5 toxin produced by certain enterohemorrhagic E. coli strains which cleaves host chaperone BiP in endoplasmic reticulum (ER), leading to ER stress-mediated cytotoxicity. Previous study suggested that protein disulfide isomerase (PDI), an enzyme which catalyzes the formation and breakage of disulfide bonds in proteins, regulates AB5 toxin such as cholera toxin by unfolding of A subunit, leading to its translocation into cytosol to induce disease. Although SubAB targets ER and has similar A subunit to that of other AB5 toxins, it is unclear whether PDI can modulate the SubAB function. Here we determined the role of PDI on SubAB-induced BiP cleavage, ER stress response and cytotoxicity in HeLa cells. We found that PDI knockdown significantly suppressed SubAB-induced BiP cleavage and eIF2α phosphorylation. The accumulation of SubAB in ER was perturbed upon PDI knockdown. Finally, cell viability assay showed that PDI knockdown and PDI inhibitor canceled the SubAB-induced cytotoxicity. Present results suggested that SubAB, after cellular uptake, translocates into ER and interacts with BiP that might be modulated by PDI. Identification of pivotal role of host proteins on bacterial toxin to elicit its pathogenesis is necessary basis for development of potential chemotherapy and new diagnostic strategy for control of toxin-producing bacterial infections.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Proteínas de Escherichia coli/toxicidade , Isomerases de Dissulfetos de Proteínas/metabolismo , Subtilisinas/toxicidade , Morte Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Técnicas de Silenciamento de Genes , Células HeLa , Proteínas de Choque Térmico/metabolismo , Interações entre Hospedeiro e Microrganismos/genética , Humanos , MAP Quinase Quinase 4/metabolismo , Fosforilação , Isomerases de Dissulfetos de Proteínas/antagonistas & inibidores , Isomerases de Dissulfetos de Proteínas/genética , RNA Interferente Pequeno
13.
Chem Pharm Bull (Tokyo) ; 68(4): 363-368, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32238653

RESUMO

Poly(D,L-lactide-co-glycolic) acid (PLGA) is a synthetic copolymer that has been used to design micro/nanoparticles as a carrier for macromolecules, such as protein and nucleic acids, that can be internalized by the endocytosis pathway. However, it is difficult to control the intracellular delivery to target organelles. Here we report an intracellular delivery system of nanoparticles modified with bacterial cytotoxins to the endoplasmic reticulum (ER) and anti-inflammatory activity of the nanoparticles. Subtilase cytotoxin (SubAB) is a bacterial toxin in certain enterohemorrhagic Escherichia coli (EHEC) strains that cleaves the host ER chaperone BiP and suppresses nuclear factor-kappaB (NF-κB) activation and nitric oxide (NO) generation in macrophages at sub-lethal concentration. PLGA-nanoparticles were modified with oligo histidine-tagged (6 × His-tagged) recombinant SubAB (SubAB-PLGA) through a pH-sensitive linkage, and their translocation to the ER in macrophage cell line J774.1 cells, effects on inducible NO synthase (iNOS), and levels of tumor necrosis factor (TNF)-α cytokine induced by lipopolysaccharide (LPS) were examined. Compared with free SubAB, SubAB-PLGA was significantly effective in BiP cleavage and the induction of the ER stress marker C/EBP homologous protein (CHOP) in J774.1 cells. Furthermore, SubAB-PLGA attenuated LPS-stimulated induction of iNOS and TNF-α. Our findings provide useful information for protein delivery to macrophages and may encourage therapeutic applications of nanoparticles to the treatment of inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Toxinas Bacterianas/farmacologia , Sistemas de Liberação de Medicamentos , Macrófagos/efeitos dos fármacos , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Animais , Anti-Inflamatórios/química , Toxinas Bacterianas/química , Células Cultivadas , Portadores de Fármacos/química , Escherichia coli/química , Concentração de Íons de Hidrogênio , Camundongos , Estrutura Molecular , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/síntese química , Propriedades de Superfície
14.
Chem Biodivers ; 17(9): e2000326, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32744414

RESUMO

Medical fungi polysaccharides belong to a very important species of biological macromolecules, which are the basic substances that effectively maintain and ensure the normal operation of biological life activities. However, research on extraction and biological activity of Inonotus cuticularis polysaccharides has never been reported. In this study, the optimum yield of Inonotus cuticularis polysaccharides was determined by the orthogonal experimental design. The highest yield of 3.10±0.06 % was obtained with extraction temperature of 80 °C, extraction time of 150 min, and water to raw material ratio of 30 mL/g and repeated twice. After deproteinization for 5 times, the protein removal rate reached 70.10±1.75 %, and the content of polysaccharides and protein were 46.64 and 0.42 %. Infrared spectrometer indicated that Inonotus cuticularis polysaccharides are typical ß-pyranose with characteristic peaks of polysaccharides. Subsequently, the activities of scavenging free radicals for the deproteinated polysaccharides were studied. When the concentration of Inonotus cuticularis polysaccharides was 0.3 mg/mL, the scavenging activities of the sample on DPPH. , . OH, ABTS.+ and O2 .- reached 83.67±0.27, 65.21±4.82, 43.45±1.36 and 80.28±2.30 %, respectively, and the reducing power reached 0.46±0.01. The IC50 values scavenging DPPH. , . OH, ABTS.+ and O2 .- were 0.139±0.13, 0.162±0.14, 0.317±0.30 and 0.121±0.10 mg/mL, respectively. Results showed that Inonotus cuticularis polysaccharides present potential stronger antioxidant activities, especially .OH scavenging activity and reducing power. Experimental results could provide research basis of Inonotus cuticularis polysaccharides for further exploitation and utilization.


Assuntos
Antioxidantes/farmacologia , Desenho de Fármacos , Inonotus/química , Polissacarídeos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Relação Dose-Resposta a Droga , Radical Hidroxila/antagonistas & inibidores , Oxigênio/química , Picratos/antagonistas & inibidores , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Relação Estrutura-Atividade , Ácidos Sulfônicos/antagonistas & inibidores
15.
J Cell Physiol ; 234(11): 20721-20727, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31032916

RESUMO

Diagnosis and treatment at an early stage may improve survival of non-small-cell lung cancer (NSCLC). Previous studies have found that long noncoding RNA growth arrest-specific transcript 5 (GAS5) is essential to cancer progression. However, the expression and diagnostic value of GAS5 in exosomes (Exo-GAS5) remain unclear. One hundred and four participants were enrolled, including subjects with NSCLC (n = 64) and healthy subjects ( n = 40). The total Exosome Isolation Kit was applied to isolate exosomes from serum. Total RNA was extracted and the AS5 expression was analyzed using quantitative reverse transcription polymerase chain reaction. Receiver operating characteristic (ROC) curve analysis was applied to evaluate the diagnostic value of Exo-GAS5 in NSCLC. Our data indicated that the Exo-GAS5 was downregulated in patients with NSCLC compared with healthy controls ( p < 0.001). Furthermore, patients with NSCLC with larger tumor size ( p = 0.025) and advanced TNM (T: extent of the primary tumor; N: lymph node involvement; M: metastatic disease) classification ( p = 0.047) showed lower Exo-GAS5 expression. ROC curve analysis using Exo-GAS5 combined with carcinoembryonic antigen showed an area under curve (AUC) of 0.929. Exo-GAS5 could be used to distinguish patients with Stage I NSCLC with an AUC of 0.822. In conclusion, Exo-GAS5 may function as an ideal noninvasive serum-based marker for identifying patients with early NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/sangue , Exossomos/metabolismo , Neoplasias Pulmonares/sangue , RNA Longo não Codificante/sangue , RNA Longo não Codificante/metabolismo , Idoso , Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Estudos de Casos e Controles , Exossomos/genética , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , RNA Longo não Codificante/genética
16.
J Cell Biochem ; 120(4): 6237-6249, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30335900

RESUMO

Nuclear receptor coactivator 5 (NCOA5) specifically enhances estrogen receptor α-modulated transcriptional activity. As a novel tumor suppressor, depletion of NCOA5 is associated with the development of a variety of tumors, but its function in cervical cancer is currently unclear. In this study, we addressed how expression of NCOA5 changed in the development of human cervical cancer and its association with clinicopathological features, prognosis, and biology characteristics of cervical cancer. Analysis of the microarrays in the Oncomine database indicated that NCOA5 expression was lower in human cervical squamous cell carcinoma tissues than that in normal cervical tissues. That was corroborated by our experiments using fresh tissues: the expression levels of NCOA5 messenger RNA and protein were both significantly decreased in cervical cancer tissues compared with paired adjacent nontumor tissues (P < 0.01). Low expression of NCOA5 is associated with the International Federation of Gynecology and Obstetrics stage ( P = 0.043) and histological grade ( P = 0.018) of human cervical cancer. In addition, patients possessing low NCOA5 expression had poorer prognosis. Univariate and multivariate Cox regression analyses indicated that low NCOA5 expression may be an independent prognostic factor for poorer overall survival in cervical cancer. Further, downregulation of NCOA5 expression results in a significant increase in proliferation, migration, and invasion of HeLa cells. Data of xenograft tumor on BALB/c nude mice manifested that HeLa cells with low NCOA5 expression tend to form larger tumors than negative control ones. In contrast, overexpression of NCOA5 expression leads to the opposite results. Finally, we found that NCOA5 might affect the biological function of human cervical cancer cells by mediating the notch3 signaling pathway. These findings suggest that NCOA5 acts as a tumor suppressor to inhibit tumorigenicity, migration, and invasion, and thus represents a potential novel prognostic marker for overall survival in cervical cancer.


Assuntos
Regulação para Baixo , Coativadores de Receptor Nuclear/genética , Coativadores de Receptor Nuclear/metabolismo , Transdução de Sinais , Neoplasias do Colo do Útero/patologia , Adulto , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Camundongos , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Transplante de Neoplasias , Prognóstico , Receptor Notch3/metabolismo , Análise de Sobrevida , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo
17.
BMC Neurol ; 19(1): 228, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31558167

RESUMO

BACKGROUND: Endovascular treatment (EVT) is advocated for acute ischaemic stroke with large-vessel occlusion (LVO), but perioperative periods are challenging. This study investigated the relationship between post-EVT short-term blood pressure variability (BPV) and early outcomes in LVO patients. METHODS: We retrospectively reviewed 72 LVO patients undergoing EVT between June 2015 and June 2018. Hourly systolic and diastolic blood pressures (SBP and DBP, respectively) were recorded in the first 24 h post-EVT. BPV were evaluated as standard deviation (SD), coefficient of variation (CV), and successive variation (SV) separately for SBP and DBP. Functional independence at 3 months was defined as a modified Rankin Scale (mRS) score of 0-2. RESULTS: For 58.3% patients with favorable outcomes, the median National Institutes of Health Stroke Scale and Alberta Stroke Program Early CT scores on admission were 14 and 8, respectively. The maximum SBP ([154.3 ± 16.8] vs. [163.5 ± 15.6], P = 0.02), systolic CV ([8. 8% ± 2.0%] vs. [11.0% ± 1.8], P < 0.001), SV ([11.4 ± 2.3] vs. [14.6 ± 2.0], P < 0.001), and SD ([10.5 ± 2.4] vs. [13.8 ± 3.9], P < 0.001) were lower in patients with favorable outcomes. On multivariable logistic regression analysis, systolic SV (OR: 4.273, 95% CI: 1.030 to 17.727, P = 0.045) independently predicted unfavorable prognosis. The area under the curve was 0.868 (95% CI: 0.781 to 0.955, P < 0.001), and sensitivity and specificity were 93.3% and 73.8%, respectively, showing excellent predictive value for 3-month poor-outcomes. CONCLUSIONS: Decreased systolic SV following intra-arterial therapies result in favorable outcomes at 3 months. Systolic SV may be a novel predictor of functional prognosis in LVO patients.


Assuntos
Arteriopatias Oclusivas/fisiopatologia , Arteriopatias Oclusivas/terapia , Pressão Sanguínea/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Procedimentos Endovasculares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
18.
Future Oncol ; 15(19): 2251-2266, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31094582

RESUMO

Aim: To determine whether lymphadenectomy is associated with increased survival of women with stage IA endometrial cancer. Methods: Patients diagnosed with endometrial cancer from 2004 to 2013 and whose clinicopathologic data were recorded in the SEER database were examined. Propensity matching paired subjects with similar background variables. Before and after matching, Kaplan-Meier curves were drawn for comparison. Results: In 11,603 patients, cardiovascular disease and diabetes were the most common causes of death. Before matching, lymphadenectomy significantly improved the overall survival of stage IA/grade 3-4 patients (p = 0.013), but after matching, lymphadenectomy did not prolong survival for any grade. Sentinel lymph nodes biopsy can reduce the number of resected lymph nodes (p = 8.387e-10 in Wilcox test) but can't prolong survival. Conclusion: After matching, no significant difference in survival between lymphadenectomy and nonlymphadenectomy was observed for stage IA patients, sentinel lymph nodes group had fewer lymph node removed, but didn't affect survival.


Assuntos
Neoplasias do Endométrio/cirurgia , Excisão de Linfonodo/métodos , Programa de SEER , Linfonodo Sentinela/cirurgia , Adulto , Idoso , Gerenciamento de Dados , Intervalo Livre de Doença , Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/patologia , Feminino , Humanos , Excisão de Linfonodo/efeitos adversos , Metástase Linfática/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Linfonodo Sentinela/patologia , Biópsia de Linfonodo Sentinela
19.
Biol Pharm Bull ; 42(7): 1199-1206, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257295

RESUMO

Metalloporphyrin derivatives have been investigated for their therapeutic potential for oxidative stress-related diseases because of their scavenging of reactive oxygen species (ROS). Here, we describe the synthesis, physicochemical properties, and ROS-scavenging activities of one such derivative-polyethylene glycol (PEG)-conjugated manganese protoporphyrin (PEG-MnPP). Carboxyl groups of the protoporphyrin ring at the C6 and C7 positions were first conjugated with ethylenediamine to introduce amino groups into the protoporphyrin structure. The amino groups were then reacted with succinimidyl PEG, with an average molecular weight of 2000, to obtain pegylated protoporphyrin (PEG-PP). Manganese was chelated to the protoporphyrin ring by incubating PEG-PP and manganese acetate in methanol. Dynamic light scattering and fluorescent spectrometry analyses revealed that PEG-MnPP self-assembled into nanoparticles in aqueous media with an apparent diameter of 70 nm. PEG-MnPP effectively eliminated hydrogen peroxide from cell culture media and protected cultured mammalian cells from toxic insults induced by hydrogen peroxide exposure or by 6-hydroxydopamine treatment. Intravenous administration of PEG-MnPP to mice significantly suppressed acute liver failure that had been induced by acetaminophen overdose. These data warrant additional investigation to study the therapeutic potential of PEG-MnPP as a water-soluble metalloporphyrin-based catalase mimic for oxidative stress-associated diseases.


Assuntos
Falência Hepática Aguda/tratamento farmacológico , Polietilenoglicóis/administração & dosagem , Protoporfirinas/administração & dosagem , Acetaminofen , Animais , Catalase , Linhagem Celular , Humanos , Peróxido de Hidrogênio/farmacologia , Falência Hepática Aguda/induzido quimicamente , Masculino , Camundongos Endogâmicos ICR , Polietilenoglicóis/química , Protoporfirinas/química
20.
Biochem Biophys Res Commun ; 487(3): 625-632, 2017 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-28435071

RESUMO

OBJECTIVE: Estrogen receptor alpha 36 (ER-α36), a truncated variant of ER-α, is different from other nuclear receptors of the ER-α family. Previous findings indicate that ER-α36 might be involved in cell growth, proliferation, and differentiation in carcinomas and primarily mediates non-genomic estrogen signaling. However, studies on ER-α36 and cervical cancer are rare. This study aimed to detect the expression of ER-α36 in cervical cancer; the role of ER-α36 in 17-ß-estradiol (E2)-induced invasion, migration and proliferation of cervical cancer; and their probable molecular mechanisms. METHODS: Immunohistochemistry and immunofluorescence were used to determine the location of ER-α36 in cervical cancer tissues and cervical cell lines. CaSki and HeLa cell lines were transfected with lentiviruses to establish stable cell lines with knockdown and overexpression of ER-α36. Wound healing assay, transwell invasion assay, and EdU incorporation proliferation assay were performed to evaluate the migration, invasion, and proliferation ability. The phosphorylation levels of mitogen-activated protein kinases/extracellular signal-regulated kinase (MAPK/ERK) signaling molecules were examined with western blot analysis. RESULTS: ER-α36 expression was detected in both cervical cell lines and cervical cancer tissues. Downregulation of ER-α36 significantly inhibited cell invasion, migration, and proliferation. Moreover, upregulation of ER-α36 increased the invasion, migration, and proliferation ability of CaSki and HeLa cell lines. ER-α36 mediates estrogen-stimulated MAPK/ERK activation. CONCLUSION: ER-α36 is localized on the plasma membrane and cytoplasm in both cervical cancer tissues and cell lines. ER-α36 mediates estrogen-stimulated MAPK/ERK activation and regulates migration, invasion, proliferation in cervical cancer cells.


Assuntos
Movimento Celular , Receptor alfa de Estrogênio/metabolismo , Estrogênios/metabolismo , Sistema de Sinalização das MAP Quinases , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Proliferação de Células , Ativação Enzimática , Feminino , Humanos , Invasividade Neoplásica , Células Tumorais Cultivadas
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